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Koh, James

Overview:

The major effort in the lab is directed towards investigating how tumor-specific dysregulation of the pRB signaling pathway affects downstream gene expression and the cellular response to DNA damage. Four projects are currently underway. First, we are utilizing a modified chromatin immunoprecipitation approach to capture and identify genomic DNA target sequences conditionally associated with pRB-containing complexes recovered from intact chromatin in untransformed primary human cells. Second, we are investigating functional heterogeneity amongst closely related components in the pRB pathway. Specifically, we are conducting comparative analyses of the INK4 proteins p16INK4a and p18INK4c and their preferred target kinases, the cyclin dependent kinases cdk4 and cdk6. Third, in collaboration with Dr. Jeff Marks, we are developing a mammary gland organoid approach to quantitate and analyze parity-dependent DNA damage checkpoint responses in the context of the primary human mammary tissue. Finally, we are engaged in a collaborative effort with Dr. Francis Ali-Osman to investigate the role of the glutathione-S-transferase protein P1 (GSTP1) in conferring chemotherapeutic drug resistance in human gliomas. To date, we have made significant progress in these projects. We have isolated a collection of genomic clones that are preferentially bound by pRB in senescent primary human mammary epithelial cells, and we intend to characterize these candidate regulatory elements as potential downstream targets of pRB-mediated gene regulation. Interestingly, the majority of the captured sequences do not contain canonical E2F binding sites, a finding that supports our approach of seeking pRB-bound sequences without the limitation of prior assumptions regarding the identity of the DNA-binding transcription factor bound by the pRB complex. In our comparative study of the closely related INK4 proteins p16INK4a and p18INK4c, we have found that differential substrate kinase preference may provide a molecular explanation for why p16INK4a but not p18INK4c is selectively targeted for inactivation in human tumors. In an extension of our previously published studies in T-cell acute lymphoblastic leukemias, we have determined that p18INK4c is highly expressed in a series of medulloblastoma cell lines (derived by Dr. Hai Yan), and that these same cell lines have selectively lost p16INK4a expression. Re-introduction of p16INK4a into these cells induces complete cell cycle arrest, but exogenous expression of p18INK4c has no effect on proliferation. Molecular analysis of p16INK4a and p18INK4c complexes in these cells indicates that p16INK4a associates preferentially with cdk4 whereas p18INK4c binds cdk6. Although cdk4 and cdk6 are highly similar (71% amino acid identity) and are generally assumed to be functionally redundant, we have found that these two kinases differ in their ability to bypass INK4-protein induced cell cycle arrest. In the context of medulloblastomas, we are currently testing the hypothesis that cdk4 and cdk6 execute opposing functions, with cdk4 activity driving proliferation and cdk6 activity inducing differentiation and cell cycle exit. A manuscript describing these findings is currently in preparation.

Previously, we have observed that mammary glands isolated from age-matched parous and nulliparous mice differed in their response to gamma-irradiation. Essentially, glands isolated from nulliparous animals failed to undergo a DNA damage checkpoint arrest, whereas glands from parous animals ceased cellular proliferation following exposure to mutagenic insult. In collaboration with Dr. Jeffrey Marks, we will analyze luminal and basal epithelial primary cells isolated from human reduction mammoplasty tissue with the goal of identifying parity- and compartment-dependent differences in checkpoint functional response.

In collaboration with Dr. Francis Ali-Osman, we are investigating the role of GSTP1-containing protein complexes in mediating drug resistance in gliomas. Our approach exploits Dr. Ali-Osman’s extensive background in chemotherapeutic drug resistance and GSTP1 activity and my laboratory’s expertise in identifying and characterizing protein:protein interactions and functional determinants of checkpoint response and apoptosis. Through biochemical enrichment and utilization of the new Duke Proteomics facility, we have begun systematically identifying GSTP1-associated proteins from extracts of cultured human glioma cells. We will then determine how the interacting proteins contribute to GSTP1-mediated chemotherapeutic drug resistance and other functional readouts of GSTP1 activity. Using this approach, we have found that the tissue transglutaminase TGM2 forms a dynamic, non-covalent complex with GSTP1 in actively dividing gliomas, and that this complex confers resistance to clinically important DNA-damaging drugs such as cisplatin (manuscript in preparation). In the coming year, we plan to extend these results to in vivo systems and investigate whether interfering peptides that disrupt the complex could serve as sensitizing agents to improve chemotherapeutic response to cisplatin.

Positions:

Assistant Professor of Surgery

Surgery, Surgical Sciences
School of Medicine

Member of the Duke Cancer Institute

Duke Cancer Institute
School of Medicine

Education:

Ph.D. 1994

Ph.D. — University of Michigan at Ann Arbor

Grants:

Single cell analysis of intratumoral heterogeneity in parathyroid neoplasia

Administered By
Surgery, Surgical Sciences
AwardedBy
National Institutes of Health
Role
Principal Investigator
Start Date
January 16, 2015
End Date
February 28, 2017

Molecular Mechanisms of Altered Calcium Sensing in Human Parathyroid Disease

Administered By
Surgery, Surgical Sciences
AwardedBy
University of Maryland
Role
Principal Investigator
Start Date
February 01, 2012
End Date
May 31, 2015

Molecular mechanisms of altered calcium sensing in human parathyroid disease

Administered By
Surgery
AwardedBy
National Institutes of Health
Role
Co-Principal Investigator
Start Date
June 01, 2010
End Date
January 31, 2012

Publications:

Orphan Adhesion GPCR GPR64/ADGRG2 Is Overexpressed in Parathyroid Tumors and Attenuates Calcium-Sensing Receptor-Mediated Signaling.

Abnormal feedback of serum calcium to parathyroid hormone (PTH) secretion is the hallmark of primary hyperparathyroidism (PHPT). Although the molecular pathogenesis of parathyroid neoplasia in PHPT has been linked to abnormal expression of genes involved in cell growth (e.g., cyclin D1, retinoblastoma, and β-catenin), the molecular basis of abnormal calcium sensing by calcium-sensing receptor (CaSR) and PTH hypersecretion in PHPT are incompletely understood. Through gene expression profiling, we discovered that an orphan adhesion G protein-coupled receptor (GPCR), GPR64/ADGRG2, is expressed in human normal parathyroid glands and is overexpressed in parathyroid tumors from patients with PHPT. Using immunohistochemistry, Western blotting, and coimmunoprecipitation, we found that GPR64 is expressed on the cell surface of parathyroid cells, is overexpressed in parathyroid tumors, and physically interacts with the CaSR. By using reporter gene assay and GPCR second messenger readouts we identified Gαs, 3',5'-cyclic adenosine monophosphate (cAMP), protein kinase A, and cAMP response element binding protein (CREB) as the signaling cascade downstream of GPR64. Furthermore, we found that an N-terminally truncated human GPR64 is constitutively active and a 15-amino acid-long peptide C-terminal to the GPCR proteolysis site (GPS) of GPR64 activates this receptor. Functional characterization of GPR64 demonstrated its ability to increase PTH release from human parathyroid cells at a range of calcium concentrations. We discovered that the truncated constitutively active, but not the full-length GPR64 physically interacts with CaSR and attenuates the CaSR-mediated intracellular Ca(2+) signaling and cAMP suppression in HEK293 cells. Our results indicate that GPR64 may be a physiologic regulator of PTH release that is dysregulated in parathyroid tumors, and suggest a role for GPR64 in pathologic calcium sensing in PHPT. © 2016 American Society for Bone and Mineral Research.

Authors
Balenga, N; Azimzadeh, P; Hogue, JA; Staats, PN; Shi, Y; Koh, J; Dressman, H; Olson, JA
MLA Citation
Balenga, N, Azimzadeh, P, Hogue, JA, Staats, PN, Shi, Y, Koh, J, Dressman, H, and Olson, JA. "Orphan Adhesion GPCR GPR64/ADGRG2 Is Overexpressed in Parathyroid Tumors and Attenuates Calcium-Sensing Receptor-Mediated Signaling." Journal of bone and mineral research : the official journal of the American Society for Bone and Mineral Research (October 19, 2016).
PMID
27760455
Source
epmc
Published In
Journal of Bone and Mineral Research
Publish Date
2016
DOI
10.1002/jbmr.3023

Single-cell functional analysis of parathyroid adenomas reveals distinct classes of calcium sensing behaviour in primary hyperparathyroidism.

Primary hyperparathyroidism (PHPT) is a common endocrine neoplastic disorder caused by a failure of calcium sensing secondary to tumour development in one or more of the parathyroid glands. Parathyroid adenomas are comprised of distinct cellular subpopulations of variable clonal status that exhibit differing degrees of calcium responsiveness. To gain a clearer understanding of the relationship among cellular identity, tumour composition and clinical biochemistry in PHPT, we developed a novel single cell platform for quantitative evaluation of calcium sensing behaviour in freshly resected human parathyroid tumour cells. Live-cell intracellular calcium flux was visualized through Fluo-4-AM epifluorescence, followed by in situ immunofluorescence detection of the calcium sensing receptor (CASR), a central component in the extracellular calcium signalling pathway. The reactivity of individual parathyroid tumour cells to extracellular calcium stimulus was highly variable, with discrete kinetic response patterns observed both between and among parathyroid tumour samples. CASR abundance was not an obligate determinant of calcium responsiveness. Calcium EC50 values from a series of parathyroid adenomas revealed that the tumours segregated into two distinct categories. One group manifested a mean EC50 of 2.40 mM (95% CI: 2.37-2.41), closely aligned to the established normal range. The second group was less responsive to calcium stimulus, with a mean EC50 of 3.61 mM (95% CI: 3.45-3.95). This binary distribution indicates the existence of a previously unappreciated biochemical sub-classification of PHPT tumours, possibly reflecting distinct etiological mechanisms. Recognition of quantitative differences in calcium sensing could have important implications for the clinical management of PHPT.

Authors
Koh, J; Hogue, JA; Wang, Y; DiSalvo, M; Allbritton, NL; Shi, Y; Olson, JA; Sosa, JA
MLA Citation
Koh, J, Hogue, JA, Wang, Y, DiSalvo, M, Allbritton, NL, Shi, Y, Olson, JA, and Sosa, JA. "Single-cell functional analysis of parathyroid adenomas reveals distinct classes of calcium sensing behaviour in primary hyperparathyroidism." Journal of cellular and molecular medicine 20.2 (February 2016): 351-359.
Website
http://hdl.handle.net/10161/12535
PMID
26638194
Source
epmc
Published In
Journal of Cellular and Molecular Medicine
Volume
20
Issue
2
Publish Date
2016
Start Page
351
End Page
359
DOI
10.1111/jcmm.12732

Single-cell approaches for molecular classification of endocrine tumors.

In this review, we summarize recent developments in single-cell technologies that can be employed for the functional and molecular classification of endocrine cells in normal and neoplastic tissue.The emergence of new platforms for the isolation, analysis, and dynamic assessment of individual cell identity and reactive behavior enables experimental deconstruction of intratumoral heterogeneity and other contexts where variability in cell signaling and biochemical responsiveness inform biological function and clinical presentation. These tools are particularly appropriate for examining and classifying endocrine neoplasias, as the clinical sequelae of these tumors are often driven by disrupted hormonal responsiveness secondary to compromised cell signaling. Single-cell methods allow for multidimensional experimental designs incorporating both spatial and temporal parameters with the capacity to probe dynamic cell signaling behaviors and kinetic response patterns dependent upon sequential agonist challenge.Intratumoral heterogeneity in the provenance, composition, and biological activity of different forms of endocrine neoplasia presents a significant challenge for prognostic assessment. Single-cell technologies provide an array of powerful new approaches uniquely well suited for dissecting complex endocrine tumors. Studies examining the relationship between clinical behavior and tumor compositional variations in cellular activity are now possible, providing new opportunities to deconstruct the underlying mechanisms of endocrine neoplasia.

Authors
Koh, J; Allbritton, NL; Sosa, JA
MLA Citation
Koh, J, Allbritton, NL, and Sosa, JA. "Single-cell approaches for molecular classification of endocrine tumors." Current opinion in oncology 28.1 (January 2016): 43-49. (Review)
PMID
26632769
Source
epmc
Published In
Current Opinion in Oncology
Volume
28
Issue
1
Publish Date
2016
Start Page
43
End Page
49
DOI
10.1097/cco.0000000000000246

A Novel Ex Vivo Method for Visualizing Live-Cell Calcium Response Behavior in Intact Human Tumors.

The functional impact of intratumoral heterogeneity has been difficult to assess in the absence of a means to interrogate dynamic, live-cell biochemical events in the native tissue context of a human tumor. Conventional histological methods can reveal morphology and static biomarker expression patterns but do not provide a means to probe and evaluate tumor functional behavior and live-cell responsiveness to experimentally controlled stimuli. Here, we describe an approach that couples vibratome-mediated viable tissue sectioning with live-cell confocal microscopy imaging to visualize human parathyroid adenoma tumor cell responsiveness to extracellular calcium challenge. Tumor sections prepared as 300 micron-thick tissue slices retain viability throughout a >24 hour observation period and retain the native architecture of the parental tumor. Live-cell observation of biochemical signaling in response to extracellular calcium challenge in the intact tissue slices reveals discrete, heterogeneous kinetic waveform categories of calcium agonist reactivity within each tumor. Plotting the proportion of maximally responsive tumor cells as a function of calcium concentration yields a sigmoid dose-response curve with a calculated calcium EC50 value significantly elevated above published reference values for wild-type calcium-sensing receptor (CASR) sensitivity. Subsequent fixation and immunofluorescence analysis of the functionally evaluated tissue specimens allows alignment and mapping of the physical characteristics of individual cells within the tumor to specific calcium response behaviors. Evaluation of the relative abundance of intracellular PTH in tissue slices challenged with variable calcium concentrations demonstrates that production of the hormone can be dynamically manipulated ex vivo. The capability of visualizing live human tumor tissue behavior in response to experimentally controlled conditions opens a wide range of possibilities for personalized ex vivo therapeutic testing. This highly adaptable system provides a unique platform for live-cell ex vivo provocative testing of human tumor responsiveness to a range of physiological agonists or candidate therapeutic compounds.

Authors
Koh, J; Hogue, JA; Sosa, JA
MLA Citation
Koh, J, Hogue, JA, and Sosa, JA. "A Novel Ex Vivo Method for Visualizing Live-Cell Calcium Response Behavior in Intact Human Tumors." PloS one 11.8 (January 2016): e0161134-.
PMID
27537691
Source
epmc
Published In
PloS one
Volume
11
Issue
8
Publish Date
2016
Start Page
e0161134
DOI
10.1371/journal.pone.0161134

Reversible cell cycle inhibition and premature aging features imposed by conditional expression of p16Ink4a.

The cyclin-dependent kinase (Cdk) inhibitor p16(Ink4a) (p16) is a canonical mediator of cellular senescence and accumulates in aging tissues, where it constrains proliferation of some progenitor cells. However, whether p16 induction in tissues is sufficient to inhibit cell proliferation, mediate senescence, and/or impose aging features has remained unclear. To address these issues, we generated transgenic mice that permit conditional p16 expression. Broad induction at weaning inhibited proliferation of intestinal transit-amplifying and Lgr5+ stem cells and rapidly imposed features of aging, including hair loss, skin wrinkling, reduced body weight and subcutaneous fat, an increased myeloid fraction in peripheral blood, poor dentition, and cataracts. Aging features were observed with multiple combinations of p16 transgenes and transactivators and were largely abrogated by a germline Cdk4 R24C mutation, confirming that they reflect Cdk inhibition. Senescence markers were not found, and de-induction of p16, even after weeks of sustained expression, allowed rapid recovery of intestinal cell proliferation and reversal of aging features in most mice. These results suggest that p16-mediated inhibition of Cdk activity is sufficient to inhibit cell proliferation and impose aging features in somatic tissues of mammals and that at least some of these aging features are reversible.

Authors
Boquoi, A; Arora, S; Chen, T; Litwin, S; Koh, J; Enders, GH
MLA Citation
Boquoi, A, Arora, S, Chen, T, Litwin, S, Koh, J, and Enders, GH. "Reversible cell cycle inhibition and premature aging features imposed by conditional expression of p16Ink4a." Aging cell 14.1 (February 2015): 139-147.
PMID
25481981
Source
epmc
Published In
Aging Cell
Volume
14
Issue
1
Publish Date
2015
Start Page
139
End Page
147
DOI
10.1111/acel.12279

The senescent methylome and its relationship with cancer, ageing and germline genetic variation in humans.

Cellular senescence is a stable arrest of proliferation and is considered a key component of processes associated with carcinogenesis and other ageing-related phenotypes. Here, we perform methylome analysis of actively dividing and deeply senescent normal human epithelial cells.We identify senescence-associated differentially methylated positions (senDMPs) from multiple experiments using cells from one donor. We find that human senDMP epigenetic signatures are positively and significantly correlated with both cancer and ageing-associated methylation dynamics. We also identify germline genetic variants, including those associated with the p16INK4A locus, which are associated with the presence of in vivo senDMP signatures. Importantly, we also demonstrate that a single senDMP signature can be effectively reversed in a newly-developed protocol of transient senescence reversal.The senDMP signature has significant potential for understanding some of the key (epi)genetic etiological factors that may lead to cancer and age-related diseases in humans.

Authors
Lowe, R; Overhoff, MG; Ramagopalan, SV; Garbe, JC; Koh, J; Stampfer, MR; Beach, DH; Rakyan, VK; Bishop, CL
MLA Citation
Lowe, R, Overhoff, MG, Ramagopalan, SV, Garbe, JC, Koh, J, Stampfer, MR, Beach, DH, Rakyan, VK, and Bishop, CL. "The senescent methylome and its relationship with cancer, ageing and germline genetic variation in humans." Genome biology 16 (January 2015): 194-.
PMID
26381124
Source
epmc
Published In
Genome Biology: biology for the post-genomic era
Volume
16
Publish Date
2015
Start Page
194
DOI
10.1186/s13059-015-0748-4

Functional and genetic studies of isolated cells from parathyroid tumors reveal the complex pathogenesis of parathyroid neoplasia.

Parathyroid adenomas (PAs) causing primary hyperparathyroidism (PHPT) are histologically heterogeneous yet have been historically viewed as largely monotypic entities arising from clonal expansion of a single transformed progenitor. Using flow cytometric analysis of resected adenomatous parathyroid glands, we have isolated and characterized chief cells, oxyphil cells, and tumor-infiltrating lymphocytes. The parathyroid chief and oxyphil cells produce parathyroid hormone (PTH), express the calcium-sensing receptor (CASR), and mobilize intracellular calcium in response to CASR activation. Parathyroid tumor infiltrating lymphocytes are T cells by immunophenotyping. Under normocalcemic conditions, oxyphil cells produce ∼50% more PTH than do chief cells, yet display significantly greater PTH suppression and calcium flux response to elevated calcium. In contrast, CASR expression and localization are equivalent in the respective parathyroid cell populations. Analysis of tumor clonality using X-linked inactivation assays in a patient-matched series of intact tumors, preparatively isolated oxyphil and chief cells, and laser-captured microdissected PA specimens demonstrate polyclonality in 5 of 14 cases. These data demonstrate the presence of functionally distinct oxyphil and chief cells within parathyroid primary adenomas and provide evidence that primary PA can arise by both clonal and polyclonal mechanisms. The clonal differences, biochemical activity, and relative abundance of these parathyroid adenoma subpopulations likely reflect distinct mechanisms of disease in PHPT.

Authors
Shi, Y; Hogue, J; Dixit, D; Koh, J; Olson, JA
MLA Citation
Shi, Y, Hogue, J, Dixit, D, Koh, J, and Olson, JA. "Functional and genetic studies of isolated cells from parathyroid tumors reveal the complex pathogenesis of parathyroid neoplasia." Proceedings of the National Academy of Sciences of the United States of America 111.8 (February 7, 2014): 3092-3097.
PMID
24510902
Source
epmc
Published In
Proceedings of the National Academy of Sciences of USA
Volume
111
Issue
8
Publish Date
2014
Start Page
3092
End Page
3097
DOI
10.1073/pnas.1319742111

Cellular senescence mediated by p16INK4A-coupled miRNA pathways.

p16 is a key regulator of cellular senescence, yet the drivers of this stable state of proliferative arrest are not well understood. Here, we identify 22 senescence-associated microRNAs (SA-miRNAs) in normal human mammary epithelial cells. We show that SA-miRNAs-26b, 181a, 210 and 424 function in concert to directly repress expression of Polycomb group (PcG) proteins CBX7, embryonic ectoderm development (EED), enhancer of zeste homologue 2 (EZH2) and suppressor of zeste 12 homologue (Suz12), thereby activating p16. We demonstrate the existence of a tight positive feedback loop in which SA-miRNAs activate and re-enforce the expression of other SA-miRNA members. In contrast, PcG members restrain senescence by epigenetically repressing the expression of these SA-miRNAs. Importantly, loss of p16 leads to repression of SA-miRNA expression, intimately coupling this effector of senescence to the SA-miRNA/PcG self-regulatory loop. Taken together, our findings illuminate an important regulatory axis that underpins the transition from proliferation to cellular senescence.

Authors
Overhoff, MG; Garbe, JC; Koh, J; Stampfer, MR; Beach, DH; Bishop, CL
MLA Citation
Overhoff, MG, Garbe, JC, Koh, J, Stampfer, MR, Beach, DH, and Bishop, CL. "Cellular senescence mediated by p16INK4A-coupled miRNA pathways." Nucleic Acids Res 42.3 (February 2014): 1606-1618.
PMID
24217920
Source
pubmed
Published In
Nucleic Acids Research
Volume
42
Issue
3
Publish Date
2014
Start Page
1606
End Page
1618
DOI
10.1093/nar/gkt1096

Regulator of G protein signaling 5 is highly expressed in parathyroid tumors and inhibits signaling by the calcium-sensing receptor.

The molecular mechanisms responsible for aberrant calcium signaling in parathyroid disease are poorly understood. The loss of appropriate calcium-responsive modulation of PTH secretion observed in parathyroid disease is commonly attributed to decreased expression of the calcium-sensing receptor (CaSR), a G protein-coupled receptor. However, CaSR expression is highly variable in parathyroid adenomas, and the lack of correlation between CaSR abundance and calcium-responsive PTH kinetics indicates that mechanisms independent of CaSR expression may contribute to aberrant calcium sensing in parathyroid disease. To gain a better understanding of parathyroid tumors and the molecular determinants that drive parathyroid adenoma development, we performed gene expression profiling on a panel of 64 normal and neoplastic parathyroid tissues. The microarray data revealed high-level expression of genes known to be involved in parathyroid biology (PTH, VDR, CGA, CaSR, and GCM2). Moreover, our screen identified regulator of G protein signaling 5 (RGS5) as a candidate inhibitor of CaSR signaling. We confirmed RGS5 to be highly expressed in parathyroid adenomas relative to matched-pair normal glands. Transient expression of RGS5 in cells stably expressing CaSR resulted in dose-dependent abrogation of calcium-stimulated inositol trisphosphate production and ERK1/2 phosphorylation. Furthermore, we found that RGS5-nullizygous mice display reduced plasma PTH levels, an outcome consistent with attenuated opposition to CaSR activity. Collectively, these data suggest that RGS5 can act as a physiological regulator of calcium sensing by CaSR in the parathyroid gland. The abnormally elevated expression of RGS5 observed in parathyroid adenomas could thus represent a novel mechanism of CaSR desensitization in patients with primary hyperparathyroidism.

Authors
Koh, J; Dar, M; Untch, BR; Dixit, D; Shi, Y; Yang, Z; Adam, MA; Dressman, H; Wang, X; Gesty-Palmer, D; Marks, JR; Spurney, R; Druey, KM; Olson, JA
MLA Citation
Koh, J, Dar, M, Untch, BR, Dixit, D, Shi, Y, Yang, Z, Adam, MA, Dressman, H, Wang, X, Gesty-Palmer, D, Marks, JR, Spurney, R, Druey, KM, and Olson, JA. "Regulator of G protein signaling 5 is highly expressed in parathyroid tumors and inhibits signaling by the calcium-sensing receptor." Mol Endocrinol 25.5 (May 2011): 867-876.
PMID
21393447
Source
pubmed
Published In
Molecular endocrinology (Baltimore, Md.)
Volume
25
Issue
5
Publish Date
2011
Start Page
867
End Page
876
DOI
10.1210/me.2010-0277

Severe obesity is associated with symptomatic presentation, higher parathyroid hormone levels, and increased gland weight in primary hyperparathyroidism.

CONTEXT: A relationship between primary hyperparathyroidism (PHPT) and obesity has been observed but is incompletely understood. Furthermore, obesity has been associated with vitamin D deficiency, suggesting that the three conditions may be linked. OBJECTIVE: We hypothesized that PHPT in morbidly obese patients is more severe and that the difference may be explained by vitamin D deficiency. DESIGN AND SETTING, PARTICIPANTS, AND OUTCOME MEASURES: Records of 196 patients with surgically treated PHPT and known body mass index (BMI) were examined. Patients were stratified into three BMI groups: group I (nonobese), BMI < 25 kg/m(2) (n = 54); group II (non-severely obese), BMI 25-34 kg/m(2) (n = 102); and group III (severely obese), BMI 35 kg/m(2) or greater (n = 40). RESULTS: Preoperative PTH levels were higher in group ΙΙΙ compared with group Ι (181 ± 153 vs. 140 ± 80 pg/ml, p = 0.04). Group III patients had larger tumors on average compared with group I (1.8 ± 1.5 vs. 1.04 ± 1.5 g, P = 0.0002). In group III, BMI positively correlated with parathyroid tumor weight (r = 0.5, P = 0.002). Postoperative PTH was higher in group III compared with group Ι (61 ± 41 vs. 44 ± 28 pg/ml, P = 0.02). There was higher frequency of depression, musculoskeletal symptoms, weakness, and gastroesophageal reflux disease in group III patients. CONCLUSIONS: BMI positively correlated with parathyroid tumor weight independent of vitamin D. Severely obese patients have larger parathyroid tumor weight, higher pre- and postoperative PTH, and greater symptoms.

Authors
Adam, MA; Untch, BR; Danko, ME; Stinnett, S; Dixit, D; Koh, J; Marks, JR; Olson, JA
MLA Citation
Adam, MA, Untch, BR, Danko, ME, Stinnett, S, Dixit, D, Koh, J, Marks, JR, and Olson, JA. "Severe obesity is associated with symptomatic presentation, higher parathyroid hormone levels, and increased gland weight in primary hyperparathyroidism." J Clin Endocrinol Metab 95.11 (November 2010): 4917-4924.
PMID
20685860
Source
pubmed
Published In
Journal of Clinical Endocrinology and Metabolism
Volume
95
Issue
11
Publish Date
2010
Start Page
4917
End Page
4924
DOI
10.1210/jc.2010-0666

Primary cilium-dependent and -independent hedgehog signaling inhibits p16INK4A

In a genome-wide siRNA analysis of p16INK4a (p16) modulators, we identify the Hedgehog (Hh) pathway component SUFU and formally demonstrate that Hh signaling promotes mitogenesis by suppression of p16. A fragment of the Hh-responsive GLI2 transcription factor directly binds and inhibits the p16 promoter and senescence is associated with the loss of nuclear GLI2. Hh components partially reside in the primary cilium (PC), and the small fraction of cells in mass culture that elaborate a PC have the lowest expression of p16. Suppression of p16 is effected by both PC-dependent and -independent routes, and ablation of p16 renders cells insensitive to an Hh inhibitor and increases PC formation. These results directly link a well-established developmental mitogenic pathway with a key tumor suppressor and contribute to the molecular understanding of replicative senescence, Hh-mediated oncogenesis, and potentially the role of p16 in aging. © 2010 Elsevier Inc.

Authors
Bishop, CL; Bergin, A-MH; Fessart, D; Borgdorff, V; Hatzimasoura, E; Garbe, JC; Stampfer, MR; Koh, J; Beach, DH
MLA Citation
Bishop, CL, Bergin, A-MH, Fessart, D, Borgdorff, V, Hatzimasoura, E, Garbe, JC, Stampfer, MR, Koh, J, and Beach, DH. "Primary cilium-dependent and -independent hedgehog signaling inhibits p16INK4A." Molecular Cell 40.4 (2010): 533-547.
PMID
21095584
Source
scival
Published In
Molecular Cell
Volume
40
Issue
4
Publish Date
2010
Start Page
533
End Page
547
DOI
10.1016/j.molcel.2010.10.027

Utility of p16 immunohistochemistry for the identification of Lynch syndrome

Purpose: Immunohistochemistry for mismatch repair proteins has shown utility in the identification of Lynch syndrome, but majority of tumors with loss of MLH1expression are due to sporadic hypermethylation of the MLH1 promoter. These tumors can also show epigenetic silencing of other genes, such as p16. The aim of our study is to evaluate the utility of p16 immunohistochemistry in the prediction of MLH1germline mutations. Experimental Design: p16 immunohistochemistry was appropriately evaluated in 79 colorectal cancers with loss of MLH1 expression. Methylation of MLH1 and p16 were quantitatively studied using real-time PCR assay Methylight. BRAF V600E mutation in tumor tissue was also investigated. Genetic testing for germline mutation of MLH1 was made on 52 patients. Results: Loss of p16 expression was seen in 21 of 79 samples (26.6%). There was found statistically significant association between p16 expression and p16 methylation (P < 0.001), MLH1 methylation (P < 0.001), and BRAF mutation (P < 0.005). All tumors with loss of p16 expression showed hypermethylation of p16 (21 of 21), 95.2% (20 of 21) showed MLH1 methylation, and 71.4% (15 of 21) were mutated for BRAF V600E. Mutational analysis showed pathogenic germline mutations in 8 of the patients, harboring 10 tumors. All 10 of these tumors showed normal staining of p16 in the immunochemical analysis. Conclusions: p16 immunohistochemistry is a good surrogate marker for p16 and MLH1 epigenetic silencing due to hypermethylation, and is useful as screening tool in the selection of patients for genetic testing in Lynch syndrome. ©2009 American Association for Cancer Research.

Authors
Payá, A; Alenda, C; Pérez-Carbonell, L; Rojas, E; Soto, J-L; Guillén, C; Castillejo, A; Barberá, VM; Carrato, A; Castells, A; Llor, X; Andreu, M; Koh, J; Enders, GH; Benlloch, S; Jover, R
MLA Citation
Payá, A, Alenda, C, Pérez-Carbonell, L, Rojas, E, Soto, J-L, Guillén, C, Castillejo, A, Barberá, VM, Carrato, A, Castells, A, Llor, X, Andreu, M, Koh, J, Enders, GH, Benlloch, S, and Jover, R. "Utility of p16 immunohistochemistry for the identification of Lynch syndrome." Clinical Cancer Research 15.9 (2009): 3156-3162.
PMID
19383812
Source
scival
Published In
Clinical cancer research : an official journal of the American Association for Cancer Research
Volume
15
Issue
9
Publish Date
2009
Start Page
3156
End Page
3162
DOI
10.1158/1078-0432.CCR-08-3116

Cyclin D-1, interleukin-6, HER-2/neu, transforming growth factor receptor-II and prediction of relapse in women with early stage, hormone receptor-positive breast cancer treated with tamoxifen.

We hypothesized that amplification or overexpression of HER-2 (c-erbB-2), the Ki-67 antigen (Mib1), cyclin D-1 (CD1), interleukin-6 (IL-6), or the transforming growth factor beta II receptor, (TGFbetaRII), would predict relapse in women with early stage, estrogen (ER) and/or progesterone receptor (PR) positive breast cancer treated with tamoxifen. Conditional logistic regression models and a new novel analytic method - support vector machines (SVM) were used to assess the effect of multiple variables on treatment outcome. All patients had stage I-IIIa breast cancer (AJCC version 5). We paired 63 patients who were disease-free on or after tamoxifen with 63 patients who had relapsed (total 126); both disease-free and relapsed patients were matched by duration of tamoxifen therapy and time to recurrence. These 126 patients also served as the training set for SVM analysis and 18 other patients used as a validation set for SVM. In a multivariate analysis, larger tumor size, increasing extent of lymph node involvement, and poorer tumor grade were significant predictors of relapse. When HER-2 or CD1 were added to the model both were borderline significant predictors of relapse. The SVM model, after including all of the clinical and marker variables in the 126 patients as a training set, correctly predicted relapse in 78% of the 18 patient validation samples. In this trial, HER-2 and CD1 proved of borderline significance as predictive factors for recurrence on tamoxifen. An SVM model that included all clinical and biologic variables correctly predicted relapse in >75% of patients.

Authors
Muss, HB; Bunn, JY; Crocker, A; Plaut, K; Koh, J; Heintz, N; Rincon, M; Weaver, DL; Tam, D; Beatty, B; Kaufman, P; Donovan, M; Verbel, D; Weiss, L
MLA Citation
Muss, HB, Bunn, JY, Crocker, A, Plaut, K, Koh, J, Heintz, N, Rincon, M, Weaver, DL, Tam, D, Beatty, B, Kaufman, P, Donovan, M, Verbel, D, and Weiss, L. "Cyclin D-1, interleukin-6, HER-2/neu, transforming growth factor receptor-II and prediction of relapse in women with early stage, hormone receptor-positive breast cancer treated with tamoxifen." Breast J 13.4 (July 2007): 337-345.
PMID
17593037
Source
pubmed
Published In
The Breast Journal
Volume
13
Issue
4
Publish Date
2007
Start Page
337
End Page
345
DOI
10.1111/j.1524-4741.2007.00440.x

Induction of the tumor-suppressor p16(INK4a) within regenerative epithelial crypts in ulcerative colitis.

p16(INK4a) is a major tumor-suppressor protein, but its regulation and settings of fuction remain poorly understood. To explore the notion that p16 is induced in vivo in response to replicative stress, we examined p16 expression in tissues from human ulcerative colitis (UC; n = 25) and normal controls (n = 20). p16 was expressed strongly in UC-associated neoplasms (n = 17), as seen previously in sporadic colonic neoplasms. In non-neoplastic UC epithelium, p16 was expressed in 33% of crypts (the proliferative compartment) compared to < 1% of normal controls. p16 expression did not correlate with degree of inflammation but did correlate with the degree of crypt architecture distortion (P = .002)-a reflection of epithelial regeneration. In coimmunofluorescence studies with Ki67, p16 expression was associated with cell cycle arrest (P < .001). Both UC and normal crypts displayed evidence for the activation of the DNA damage checkpoint pathway, and p16 was induced in primary cultures of normal epithelial cells by ionizing irradiation (IR). However, induction by IR displayed delayed kinetics, implying that p16 is not an immediate target of the checkpoint pathway. These findings support a model in which p16 is induced as an "emergency brake" in cells experiencing sustained replicative stress.

Authors
Furth, EE; Gustafson, KS; Dai, CY; Gibson, SL; Menard-Katcher, P; Chen, T; Koh, J; Enders, GH
MLA Citation
Furth, EE, Gustafson, KS, Dai, CY, Gibson, SL, Menard-Katcher, P, Chen, T, Koh, J, and Enders, GH. "Induction of the tumor-suppressor p16(INK4a) within regenerative epithelial crypts in ulcerative colitis." Neoplasia 8.6 (June 2006): 429-436.
PMID
16820088
Source
pubmed
Published In
Neoplasia (New York, N.Y.)
Volume
8
Issue
6
Publish Date
2006
Start Page
429
End Page
436
DOI
10.1593/neo.06169

Detailed computational study of p53 and p16: using evolutionary sequence analysis and disease-associated mutations to predict the functional consequences of allelic variants.

Deciding whether a missense allelic variant affects protein function is important in many contexts. We previously demonstrated that a detailed analysis of p53 intragenic conservation correlates with somatic mutation hotspots. Here we refine these evolutionary studies and expand them to the p16/Ink4a gene. We calculated that in order for 'absolute conservation' of a codon across multiple species to achieve P<0.05, the evolutionary substitution database must contain at least 3(M) variants, where M equals the number of codons in the gene. Codons in p53 were divided into high (73% of codons), intermediate (29% of codons), and low (0 codons) likelihood of being mutation hotspots. From a database of 263 somatic missense p16 mutations, we identified only four codons that are mutational hotspots at P<0.05 (8 mutations). However, data on function, structure, and disease association support the conclusion that 11 other codons with > or =5 somatic mutations also likely indicate functionally critical residues, even though P0.05. We calculated p16 evolution using amino acid substitution matrices and nucleotide substitution distances. We looked for evolutionary parameters at each codon that would predict whether missense mutations were disease associated or disrupted function. The current p16 evolutionary substitution database is too small to determine whether observations of 'absolute conservation' are statistically significant. Increasing the number of sequences from three to seven significantly improved the predictive value of evolutionary computations. The sensitivity and specificity for conservation scores in predicting disease association of p16 codons is 70-80%. Despite the small p16 sequence database, our calculations of high conservation correctly predicted loss of cell cycle arrest function in 75% of tested codons, and low conservation correctly predicted wild-type function in 80-90% of codons. These data validate our hypothesis that detailed evolutionary analyses help predict the consequences of missense amino-acid variants.

Authors
Greenblatt, MS; Beaudet, JG; Gump, JR; Godin, KS; Trombley, L; Koh, J; Bond, JP
MLA Citation
Greenblatt, MS, Beaudet, JG, Gump, JR, Godin, KS, Trombley, L, Koh, J, and Bond, JP. "Detailed computational study of p53 and p16: using evolutionary sequence analysis and disease-associated mutations to predict the functional consequences of allelic variants." Oncogene 22.8 (February 27, 2003): 1150-1163.
PMID
12606942
Source
pubmed
Published In
Oncogene: Including Oncogene Reviews
Volume
22
Issue
8
Publish Date
2003
Start Page
1150
End Page
1163
DOI
10.1038/sj.onc.1206101

Influence of human p16(INK4) and p21(CIP1) on the in vitro activity of recombinant Plasmodium falciparum cyclin-dependent protein kinases.

The regulatory mechanisms of most cyclin dependent protein kinases (CDKs) are well understood and are highly conserved in eukaryotes. CDKs from the malaria parasite, Plasmodium falciparum, appear to be regulated in a similar manner with regard to cyclin binding and phosphorylation. In order to further understand their regulatory mechanisms, we examined two classes of cyclin dependent kinase inhibitors (CDIs) to inhibit a panel of plasmodial CDKs. We find that Pfmrk and PfPK5 are inhibited by heterologous p21(CIP1) with varying degrees of inhibition. In contrast, PfPK6, a kinase with sequence features characteristic of both a CDK and MAP kinase, is unaffected by this CDI. Furthermore, the CDK4/6 specific CDI, p16(INK4), fails to inhibit these plasmodial CDKs. Taken together, these results suggest that plasmodial CDKs may be regulated by the binding of inhibitory proteins in vivo.

Authors
Li, Z; Le Roch, K; Geyer, JA; Woodard, CL; Prigge, ST; Koh, J; Doerig, C; Waters, NC
MLA Citation
Li, Z, Le Roch, K, Geyer, JA, Woodard, CL, Prigge, ST, Koh, J, Doerig, C, and Waters, NC. "Influence of human p16(INK4) and p21(CIP1) on the in vitro activity of recombinant Plasmodium falciparum cyclin-dependent protein kinases." Biochem Biophys Res Commun 288.5 (November 16, 2001): 1207-1211.
PMID
11700040
Source
pubmed
Published In
Biochemical and Biophysical Research Communications
Volume
288
Issue
5
Publish Date
2001
Start Page
1207
End Page
1211
DOI
10.1006/bbrc.2001.5920

An antibody to p16INK4A recognizes a modified form of galectin-3.

Galectin-3 is a carbohydrate binding protein involved in multiple processes including cell-cycle regulation and apoptosis. The ability of galectin-3 to protect cells from apoptosis is dependent upon a region of the protein known as a BH-1 domain for its homology to the anti-apoptotic protein Bcl-2. Here, we show that a monoclonal antibody (MAb) to the human tumor suppressor protein p16INK4A recognizes a post-translationally modified form of human galectin-3. The modified form is detectable in only a subset of cell types expressing galectin-3, indicating that the modification is cell-type-specific. Although there is little amino acid sequence homology between p16INK4a and galectin-3, we show by epitope mapping that the modification directly affects the structure of galectin-3's BH-1 domain. Elucidation of the nature of this modification might provide further insight into galectin-3 function.

Authors
Gump, J; Koh, J
MLA Citation
Gump, J, and Koh, J. "An antibody to p16INK4A recognizes a modified form of galectin-3." Hybridoma 20.3 (June 2001): 167-174.
PMID
11461665
Source
pubmed
Published In
Hybridoma
Volume
20
Issue
3
Publish Date
2001
Start Page
167
End Page
174
DOI
10.1089/027245701750293493

The COOH terminus of p18INK4C distinguishes function from p16INK4A.

The INK4 family of proteins consists of four members which can block progression from the G(1)-to-S phase of the cell cycle by inhibiting the activity of cyclin dependent kinases (cdks) 4 and 6. Although the gene encoding p16(INK4a) is commonly inactivated in human tumors, p18(INK4c) is rarely altered. We show here that overexpression of p18(INK4c) does not block cell cycle progression in a T-cell acute lymphocytic leukemia cell line (CEM) sensitive to p16(INK4a)-mediated G(1) arrest. A chimera consisting of the kinase-binding region of p16(INK4a) fused to the COOH terminus of p18(INK4c) is active in all known biochemical assays for INK4 function, but it does not arrest CEM cells. These data imply a novel level of p18(INK4c) regulation mediated through the COOH terminus and suggest that functional differences might underlie the distinct mutational profiles observed for p16(INK4a) and p18(INK4c) in tumors.

Authors
Gump, J; Turner, S; Koh, J
MLA Citation
Gump, J, Turner, S, and Koh, J. "The COOH terminus of p18INK4C distinguishes function from p16INK4A." Cancer Res 61.10 (May 15, 2001): 3863-3868.
PMID
11358797
Source
pubmed
Published In
Cancer Research
Volume
61
Issue
10
Publish Date
2001
Start Page
3863
End Page
3868

Cyclin D1 predicts tamoxifen benefit in women with early stage ER+ breast cancer

Tamoxifen (tam) significantly improves survival for almost 30% of patients with early stage breast cancer and ER+ tumors. However, because it is difficult to determine a priori which patients are most likely to benefit from tam treatment, predictive indicators for tam responsiveness are needed. Cyclin D1 (CD1) is a critical regulator of cellular proliferation in the breast epithelium. Recent work indicates that CD1 can bind the ER and that the D1/ER complex can induce ER-dependent gene expression even in the absence of estradiol. Because CD1 and ER are selectively over-expressed in many breast tumors. D1/ER complexes could confer an estrogen-independent means of growth signaling and render breast cancer cells resistant to antiestrogens such as tam. Therefore, we hypothesized that tumors which overexpress CD1 would be more likely to be resistant to tam. To test this, we investigated whether patients whose tumors express high levels of CD1 were more likely to have relapsed during tamoxifen treatment. Methods: Eligibility restricted to patients with ER+, Stage I-IIIa breast cancer treated with tam. Relapsed (TR) and non-relapsed (TNR) patients were matched for time on tam and lime of follow-up. CD1 was measured by IHC using paraffin-embedded tissues and the NCL-cyclin D1 antibody (Novacastra). CD1+ status is defined as an H score value (cumulative score of 100 tumor nuclei evaluated for presence and intensity of staining on a scale of 0-3) of >65. Tumors from 80 patients have been evaluated to date. Results: Preliminary results are shown below: Status N CD1+ [n;(%)] Age<50 [n;(%)] Node-neg [n;(%)] Relapse 40 30 (75.0%) 8 (20.0%) 14 (35.0%) No relapse 40 21 (52.5%) 1 (2.5%) 22 (55.0%) Conclusion: These early data suggest that elevated cyclin D1 expression is a strong predictor of TR. Supported by The Breast Cancer Research Foundation.

Authors
Koh, J; Burch, P; Godin, K; Beatty, B; Pinet, M; Bunn, JY; Tam, D; Simmons-Arnold, L; Weaver, D; Muss, HB
MLA Citation
Koh, J, Burch, P, Godin, K, Beatty, B, Pinet, M, Bunn, JY, Tam, D, Simmons-Arnold, L, Weaver, D, and Muss, HB. "Cyclin D1 predicts tamoxifen benefit in women with early stage ER+ breast cancer." 2001.
Source
scival
Published In
Breast Cancer Research and Treatment
Volume
69
Issue
3
Publish Date
2001
Start Page
246-

p16(INK4a) expression begins early in human colon neoplasia and correlates inversely with markers of cell proliferation.

BACKGROUND & AIMS: p16(INK4a) is a cell cycle inhibitor and a major tumor-suppressor protein, but the regulation of p16(INK4a) is poorly understood and the physiologic settings in which it exerts its antiproliferative effects are unknown. A role for p16(INK4a) in intestinal neoplasia is suggested by the observation that the promoter region is methylated in a subset of human colon tumors. We examined the expression of the protein in specimens representing the full spectrum of neoplastic progression in the human colon and determined whether expressing cells showed evidence of cell cycle inhibition. METHODS: We studied p16(INK4a) expression by immunoprecipitation, immunoblotting, reverse-transcription polymerase chain reaction (RT-PCR), immunohistochemistry, and immunofluorescence in matched normal and neoplastic colonic tissue from 70 patients. RESULTS: p16(INK4a) expression was very low in normal mucosa, with staining observed in rare epithelial cells at the base of crypts. A distinctly higher expression was found in 4 of 7 aberrant crypt foci, 32 of 36 adenomas, 18 of 28 primary carcinomas, and 5 of 5 metastatic carcinomas. Within each neoplasm p16(INK4a) staining was heterogeneous, with higher expression commonly seen in areas bordering normal tissue. p16(INK4a) staining correlated inversely with that of Ki67, cyclin A, and the retinoblastoma protein, suggesting that cell cycle progression was inhibited. CONCLUSIONS: These results suggest that p16(INK4a) expression begins in the earliest detectable stages of neoplastic progression in the human colon and exerts a continuous, piecemeal constraint on tumor growth.

Authors
Dai, CY; Furth, EE; Mick, R; Koh, J; Takayama, T; Niitsu, Y; Enders, GH
MLA Citation
Dai, CY, Furth, EE, Mick, R, Koh, J, Takayama, T, Niitsu, Y, and Enders, GH. "p16(INK4a) expression begins early in human colon neoplasia and correlates inversely with markers of cell proliferation." Gastroenterology 119.4 (October 2000): 929-942.
PMID
11040180
Source
pubmed
Published In
Gastroenterology
Volume
119
Issue
4
Publish Date
2000
Start Page
929
End Page
942

Regulation of CDK7-carboxyl-terminal domain kinase activity by the tumor suppressor p16(INK4A) contributes to cell cycle regulation.

The eukaryotic cell cycle is regulated by cyclin-dependent kinases (CDKs). CDK4 and CDK6, which are activated by D-type cyclins during the G(1) phase of the cell cycle, are thought to be responsible for phosphorylation of the retinoblastoma gene product (pRb). The tumor suppressor p16(INK4A) inhibits phosphorylation of pRb by CDK4 and CDK6 and can thereby block cell cycle progression at the G(1)/S boundary. Phosphorylation of the carboxyl-terminal domain (CTD) of the large subunit of RNA polymerase II by general transcription factor TFIIH is believed to be an important regulatory event in transcription. TFIIH contains a CDK7 kinase subunit and phosphorylates the CTD. We have previously shown that p16(INK4A) inhibits phosphorylation of the CTD by TFIIH. Here we report that the ability of p16(INK4A) to inhibit CDK7-CTD kinase contributes to the capacity to induce cell cycle arrest. These results suggest that p16(INK4A) may regulate cell cycle progression by inhibiting not only CDK4-pRb kinase activity but also by modulating CDK7-CTD kinase activity. Regulation of CDK7-CTD kinase activity by p16(INK4A) thus may represent an alternative pathway for controlling cell cycle progression.

Authors
Nishiwaki, E; Turner, SL; Harju, S; Miyazaki, S; Kashiwagi, M; Koh, J; Serizawa, H
MLA Citation
Nishiwaki, E, Turner, SL, Harju, S, Miyazaki, S, Kashiwagi, M, Koh, J, and Serizawa, H. "Regulation of CDK7-carboxyl-terminal domain kinase activity by the tumor suppressor p16(INK4A) contributes to cell cycle regulation." Mol Cell Biol 20.20 (October 2000): 7726-7734.
PMID
11003668
Source
pubmed
Published In
Molecular and Cellular Biology
Volume
20
Issue
20
Publish Date
2000
Start Page
7726
End Page
7734

Requirements for cell cycle arrest by p16INK4a.

Analysis of tumor-derived mutations has led to the suggestion that p16INK4a, cyclin D1, cdk4, and the retinoblastoma protein (pRB) are components of a regulatory pathway that is inactivated in most tumor cells. Cell cycle arrest induced by p16INK4a, an inhibitor of cyclin D-dependent kinases, requires pRB, and it has been proposed that this G1 arrest is mediated by pRB-E2F repressor complexes. By comparing the properties of primary mouse embryonic fibroblasts specifically lacking pRB-family members, we find that pRB is insufficient for a p16INK4a-induced arrest. In addition to pRB, a second function provided by either p107 or p130, two pRB-related proteins, is required for p16INK4a to block DNA synthesis. We infer that p16INK4a-induced arrest is not mediated exclusively by pRB, but depends on the nonredundant functions of at least two pRB-family members.

Authors
Bruce, JL; Hurford, RK; Classon, M; Koh, J; Dyson, N
MLA Citation
Bruce, JL, Hurford, RK, Classon, M, Koh, J, and Dyson, N. "Requirements for cell cycle arrest by p16INK4a." Mol Cell 6.3 (September 2000): 737-742.
PMID
11030353
Source
pubmed
Published In
Molecular Cell
Volume
6
Issue
3
Publish Date
2000
Start Page
737
End Page
742

Immunohistochemical survey of p16INK4A expression in normal human adult and infant tissues.

p16INK4A is a cell cycle inhibitor that is commonly inactivated in human tumors and tumor cell lines. Despite its importance in human neoplasia, the normal pattern of p16 expression remains largely unknown. Therefore, we analyzed the immunohistochemical localization of p16 in all human organs and demonstrated that cellular p16 expression is highly selective. In adults, proliferative endometrium, breast ductal epithelium, squamous and tubal metaplastic epithelium of the uterine cervix, esophageal squamous epithelium, salivary glands, and antral gastric glands all strongly express the protein. p16 is also widely expressed in endocrine glands, including Langerhans cells in the pancreas and anterior pituicytes and Leydig and Sertoli cells in testis. Within each tissue, however, p16 expression does not correlate with cellular proliferation or maturation. In infants, p16 staining was limited to thymic Hassall's corpuscles, occasional thymic lymphocytes, and only rare pancreatic epithelial cells. Therefore, increased expression of p16 in adult tissues, as in mouse tissues, may reflect a role of p16 in cellular senescence. Restriction of p16 expression in infants to the thymus, the only organ committed to early senescence, is also consistent with such a role. Documentation of the pattern of p16 expression in normal tissues will contribute to our understanding of the normal function of this protein and to interpretation of potentially altered p16 expression in human tumors.

Authors
Nielsen, GP; Stemmer-Rachamimov, AO; Shaw, J; Roy, JE; Koh, J; Louis, DN
MLA Citation
Nielsen, GP, Stemmer-Rachamimov, AO, Shaw, J, Roy, JE, Koh, J, and Louis, DN. "Immunohistochemical survey of p16INK4A expression in normal human adult and infant tissues." Lab Invest 79.9 (September 1999): 1137-1143.
PMID
10496532
Source
pubmed
Published In
Laboratory Investigation
Volume
79
Issue
9
Publish Date
1999
Start Page
1137
End Page
1143

Molecular genetic correlates of p16, cdk4, and pRb immunohistochemistry in glioblastomas.

The vast majority of glioblastomas have CDKN2A, CDK4, or RB gene alterations that perturb the p16-cdk4-pRb cell cycle regulatory cascade. To explore whether immunohistochemical methods provide an alternative means of assessing this pathway, we studied 25 glioblastomas using a combination of molecular genetic and immunohistochemical assays. Homozygous deletion of the CDKN2A gene was detected in 12 of 25 (48%) cases, CDK4 amplification in 4 of 25 (16%) tumors, and loss of heterozygosity at the RB gene in 8 of 22 (36%) informative cases. Five of 25 (20%) glioblastomas had diffuse p16 immunohistochemical positivity. Significantly, all of these had either CDK4 amplification or RB LOH, suggesting that p16 immunopositivity only occurs in those tumors with alterations of another component in the pathway. Nineteen (76%) cases were uniformly immunonegative for p16, and 12 (48%) had CDKN2A homozygous deletions, but the remaining 7 cases lacked CDKN2A deletions, mutations and promoter methylation. All glioblastomas stained diffusely for cdk4, irrespective of CDK4 gene amplification status. Extensive pRb staining was present in most cases that maintained both RB alleles, and absent in most cases with RB loss, but there were notable discrepancies. Thus, p16 and pRb immunohistochemistry cannot replace molecular genetic analysis of this critical regulatory cascade; instead, the combined results hint at complex regulation of this cell cycle checkpoint. From a practical point of view, although p16 immunonegativity does not necessarily indicate CDKN2A deletion, diffuse positive p16 immunostaining strongly suggests either CDK4 amplification or RB loss and excludes CDKN2A deletion.

Authors
Burns, KL; Ueki, K; Jhung, SL; Koh, J; Louis, DN
MLA Citation
Burns, KL, Ueki, K, Jhung, SL, Koh, J, and Louis, DN. "Molecular genetic correlates of p16, cdk4, and pRb immunohistochemistry in glioblastomas." J Neuropathol Exp Neurol 57.2 (February 1998): 122-130.
PMID
9600204
Source
pubmed
Published In
Journal of Neuropathology and Experimental Neurology
Volume
57
Issue
2
Publish Date
1998
Start Page
122
End Page
130

Transforming growth factor beta stabilizes p15INK4B protein, increases p15INK4B-cdk4 complexes, and inhibits cyclin D1-cdk4 association in human mammary epithelial cells.

The effects of transforming growth factor beta (TGF-beta) were studied in closely related human mammary epithelial cells (HMEC), both finite-life-span 184 cells and immortal derivatives, 184A1S, and 184A1L5R, which differ in their cell cycle responses to TGF-beta but express type I and type II TGF-beta receptors and retain TGF-beta induction of extracellular matrix. The arrest-resistant phenotype was not due to loss of cyclin-dependent kinase (cdk) inhibitors. TGF-beta was shown to regulate p15INK4B expression at at least two levels: mRNA accumulation and protein stability. In TGF-beta-arrested HMEC, there was not only an increase in p15 mRNA but also a major increase in p5INK4B protein stability. As cdk4- and cdk6-associated p15INK4B increased during TGF-beta arrest of sensitive cells, there was a loss of cyclin D1, p21Cip1, and p27Kip1 from these kinase complexes, and cyclin E-cdk2-associated p27Kip1 increased. In HMEC, p15INK4B complexes did not contain detectable cyclin. p15INK4B from both sensitive and resistant cells could displace in vitro cyclin D1, p21Cip1, and p27Kip1 from cdk4 isolated from sensitive cells. Cyclin D1 could not be displaced from cdk4 in the resistant 184A1L5R cell lysates. Thus, in TGF-beta arrest, p15INK4B may displace already associated cyclin D1 from cdks and prevent new cyclin D1-cdk complexes from forming. Furthermore, p27Kip1 binding shifts from cdk4 to cyclin E-cdk2 during TGF-beta-mediated arrest. The importance of posttranslational regulation of p15INK4B by TGF-beta is underlined by the observation that in TGF-beta-resistant 184A1L5R, although the p15 transcript increased, p15INK4B protein was not stabilized and did not accumulate, and cyclin D1-cdk association and kinase activation were not inhibited.

Authors
Sandhu, C; Garbe, J; Bhattacharya, N; Daksis, J; Pan, CH; Yaswen, P; Koh, J; Slingerland, JM; Stampfer, MR
MLA Citation
Sandhu, C, Garbe, J, Bhattacharya, N, Daksis, J, Pan, CH, Yaswen, P, Koh, J, Slingerland, JM, and Stampfer, MR. "Transforming growth factor beta stabilizes p15INK4B protein, increases p15INK4B-cdk4 complexes, and inhibits cyclin D1-cdk4 association in human mammary epithelial cells." Mol Cell Biol 17.5 (May 1997): 2458-2467.
PMID
9111314
Source
pubmed
Published In
Molecular and Cellular Biology
Volume
17
Issue
5
Publish Date
1997
Start Page
2458
End Page
2467

Prevalence of germ-line mutations in p16, p19ARF, and CDK4 in familial melanoma: analysis of a clinic-based population.

Five to ten percent of individuals with melanoma have another affected family member, suggesting familial predisposition. Germ-line mutations in the cyclin-dependent kinase (CDK) inhibitor p16 have been reported in a subset of melanoma pedigrees, but their prevalence is unknown in more common cases of familial melanoma that do not involve large families with multiple affected members. We screened for germ-line mutations in p16 and in two other candidate melanoma genes, p19ARF and CDK4, in 33 consecutive patients treated for melanoma; these patients had at least one affected first or second degree relative (28 independent families). Five independent, definitive p16 mutations were detected (18%, 95% confidence interval: 6%, 37%), including one nonsense, one disease-associated missense, and three small deletions. No mutations were detected in CDK4. Disease-associated mutations in p19ARF, whose transcript is derived in part from an alternative codon reading frame of p16, were only detected in patients who also had mutations inactivating p16. We conclude that germ-line p16 mutations are present in a significant fraction of individuals who have melanoma and a positive family history.

Authors
FitzGerald, MG; Harkin, DP; Silva-Arrieta, S; MacDonald, DJ; Lucchina, LC; Unsal, H; O'Neill, E; Koh, J; Finkelstein, DM; Isselbacher, KJ; Sober, AJ; Haber, DA
MLA Citation
FitzGerald, MG, Harkin, DP, Silva-Arrieta, S, MacDonald, DJ, Lucchina, LC, Unsal, H, O'Neill, E, Koh, J, Finkelstein, DM, Isselbacher, KJ, Sober, AJ, and Haber, DA. "Prevalence of germ-line mutations in p16, p19ARF, and CDK4 in familial melanoma: analysis of a clinic-based population." Proc Natl Acad Sci U S A 93.16 (August 6, 1996): 8541-8545.
PMID
8710906
Source
pubmed
Published In
Proceedings of the National Academy of Sciences of USA
Volume
93
Issue
16
Publish Date
1996
Start Page
8541
End Page
8545

p16 inhibition of transformed and primary squamous epithelial cells.

We and others have recently shown that p16 can potently and specifically inhibit progression through the G1 phase of the replicative cycle in cells that express the retinoblastoma protein (pRB). However, none of these studies examined cell types in which p16 has been firmly implicated in tumorigenesis. We predicted that such cells would show sensitivity to p16 inhibition, perhaps conferred by proteins in addition to or other than pRB. Intragenic, inactivating mutations of p16 have been found at significant frequency in primary tumors derived from squamous epithelial cells of the esophagus (ESCC). We therefore examined p16 function in ESCC lines and in primary squamous epithelial cells cultured from mouse skin. We find that seven of eight ESCC lines tested are inhibited by p16 and fail to express the protein endogenously. The lone p16-resistant line expresses endogenous p16 but lacks functional pRB. Primary squamous epithelial cells are also inhibited by p16. These data suggest that squamous epithelial cells are generally sensitive to inhibition by a regulatory pathway that involves p16 and pRB, and that, by the time of establishment in culture, there is nearly universal inactivation of this pathway in ESCCs.

Authors
Enders, GH; Koh, J; Missero, C; Rustgi, AK; Harlow, E
MLA Citation
Enders, GH, Koh, J, Missero, C, Rustgi, AK, and Harlow, E. "p16 inhibition of transformed and primary squamous epithelial cells." Oncogene 12.6 (March 21, 1996): 1239-1245.
PMID
8649826
Source
pubmed
Published In
Oncogene: Including Oncogene Reviews
Volume
12
Issue
6
Publish Date
1996
Start Page
1239
End Page
1245

Tumour-derived p16 alleles encoding proteins defective in cell-cycle inhibition.

The cyclin-dependent kinase inhibitor p16 is a candidate tumour-suppressor protein that maps to a genomic locus strongly associated with familial melanoma and other tumour types. Screening of primary tumours and linkage analysis of familial melanoma pedigrees have identified many potential mutations in p16, but the functional significance of these sequence variants has remained unclear. We report here that p16 can act as a potent and specific inhibitor of progression through the G1 phase of the cell cycle, and we demonstrate that several tumour-derived alleles of p16 encode functionally compromised proteins. The ability of p16 to arrest cell-cycle progression generally correlates with inhibition of cyclin D1/Cdk4 kinase activity in vitro, with two exceptions among the alleles tested. In vivo, the presence of functional retinoblastoma protein appears to be necessary but may not be sufficient to confer full sensitivity to p16-mediated growth arrest. Our results provide support for the notion that p16 is an important cell-cycle regulator whose inactivation contributes to the outgrowth of human tumours.

Authors
Koh, J; Enders, GH; Dynlacht, BD; Harlow, E
MLA Citation
Koh, J, Enders, GH, Dynlacht, BD, and Harlow, E. "Tumour-derived p16 alleles encoding proteins defective in cell-cycle inhibition." Nature 375.6531 (June 8, 1995): 506-510.
PMID
7777061
Source
pubmed
Published In
Nature
Volume
375
Issue
6531
Publish Date
1995
Start Page
506
End Page
510
DOI
10.1038/375506a0

Characterization of the cystic fibrosis transmembrane conductance regulator promoter region. Chromatin context and tissue-specificity.

Expression of the gene encoding the cystic fibrosis transmembrane conductance regulator (CFTR) is tightly regulated. Using a panel of cell lines expressing different levels of CFTR mRNA, we investigated the mechanisms mediating control of CFTR transcription. In highly expressing cells, multiple sites of transcription initiation can be identified between positions -95 and +50 of the CFTR gene, and an alternatively initiated splice variant transcript is also present. Nonepithelial cell lines expressing very low levels of CFTR utilize a start site at -32. Promoter sequence elements from -83 to +111 are at least partially responsible for dictating CFTR transcriptional tissue-specificity, while multiple elements located farther 5' augment promoter strength. Analysis of the chromatin structure and methylation status of the CFTR promoter region reveals cell line differences which correlate with expression levels, suggesting that the physical context of the CFTR gene in vivo may contribute significantly to appropriate regulation of CFTR transcription. Taken together, these findings indicate that cellular control of CFTR gene expression is likely to be a complex function of several overlapping regulatory pathways.

Authors
Koh, J; Sferra, TJ; Collins, FS
MLA Citation
Koh, J, Sferra, TJ, and Collins, FS. "Characterization of the cystic fibrosis transmembrane conductance regulator promoter region. Chromatin context and tissue-specificity." J Biol Chem 268.21 (July 25, 1993): 15912-15921.
PMID
7688000
Source
pubmed
Published In
The Journal of biological chemistry
Volume
268
Issue
21
Publish Date
1993
Start Page
15912
End Page
15921

Inherited deletion at Duchenne dystrophy locus in normal male.

Authors
Bartlett, RJ; Walker, AP; Laing, NG; Koh, J; Secore, SL; Speer, MC; Pericak-Vance, M; Hung, WY; Yamaoka, LH; Siddique, T
MLA Citation
Bartlett, RJ, Walker, AP, Laing, NG, Koh, J, Secore, SL, Speer, MC, Pericak-Vance, M, Hung, WY, Yamaoka, LH, and Siddique, T. "Inherited deletion at Duchenne dystrophy locus in normal male." Lancet 1.8636 (March 4, 1989): 496-497. (Letter)
PMID
2563864
Source
pubmed
Published In
The Lancet
Volume
1
Issue
8636
Publish Date
1989
Start Page
496
End Page
497

Prenatal diagnosis using deletion studies in Duchenne muscular dystrophy.

Accurate carrier testing and prenatal diagnosis in Duchenne muscular dystrophy (DMD) families is facilitated when an Xp21 deletion is found to be segregating within a family. We discuss the results of the DNA testing in two families, one in which DNA from affected males was available for study and the other in which no DNA from an affected male was available. Factors complicating the counselling of DMD deletion families are outlined.

Authors
Speer, MC; Pericak-Vance, MA; Yamaoka, LH; Koh, J; Hung, WY; Gaskell, PC; Vance, JM; Bartlett, RJ; Roses, AD
MLA Citation
Speer, MC, Pericak-Vance, MA, Yamaoka, LH, Koh, J, Hung, WY, Gaskell, PC, Vance, JM, Bartlett, RJ, and Roses, AD. "Prenatal diagnosis using deletion studies in Duchenne muscular dystrophy." Prenat Diagn 8.6 (July 1988): 427-437.
PMID
3211845
Source
pubmed
Published In
Prenatal Diagnosis
Volume
8
Issue
6
Publish Date
1988
Start Page
427
End Page
437

Duchenne muscular dystrophy: high frequency of deletions.

DNA probes are available for Duchenne muscular dystrophy (DMD) carrier detection and prenatal diagnosis. With probes for about 25% of the proximal portion of the gene, we found the proximal probes detected deletions in 23% of nonselected DMD boys, while a single distal probe detected 17% more as deletions. The combined percentage was 39% for all probes tested. Prenatal diagnosis and carrier detection are more accurate if deletions are mapped rather than by use of restriction fragment length polymorphism analysis. The effort involved in screening all affected boys for deletions is considerably less, and provides an accurate genetic marker for subsequent prenatal diagnosis in the family and prospective counseling for female relatives. It seems likely that, once the entire gene (cDNA) is available for screening, most DMD boys will show deletions.

Authors
Bartlett, RJ; Pericak-Vance, MA; Koh, J; Yamaoka, LH; Chen, JC; Hung, WY; Speer, MC; Wapenaar, MC; Van Ommen, GJ; Bakker, E
MLA Citation
Bartlett, RJ, Pericak-Vance, MA, Koh, J, Yamaoka, LH, Chen, JC, Hung, WY, Speer, MC, Wapenaar, MC, Van Ommen, GJ, and Bakker, E. "Duchenne muscular dystrophy: high frequency of deletions." Neurology 38.1 (January 1988): 1-4.
PMID
3275902
Source
pubmed
Published In
Neurology
Volume
38
Issue
1
Publish Date
1988
Start Page
1
End Page
4

Update on the molecular genetics of Duchenne muscular dystrophy.

Three separate lines of evidence led to the assignment of the Duchenne muscular dystrophy (DMD) gene to the 21.2 band on the short arm of the X chromosome. A portion of the putative gene, thought to extend over 1-2 million base pairs has been recently cloned. DNA probes from the Xp21.2 region detect large deletions in 5-20% DMD boys and are presumed to lead to the DMD phenotype in those individuals. Deletions have also been noted in the DNA of patients with Becker muscular dystrophy. These exciting developments have a direct bearing on carrier detection and prenatal diagnosis. Prenatal diagnosis in deletion families approaches greater than 99% accuracy and can be utilized to save 50% of normal male fetuses carried by carrier mothers who would otherwise choose to abort all male fetuses.

Authors
Siddique, T; Bartlett, R; Pericak-Vance, M; Yamaoka, L; Koh, J; Chen, J; Hung, WY; Kandt, R; Roses, AD
MLA Citation
Siddique, T, Bartlett, R, Pericak-Vance, M, Yamaoka, L, Koh, J, Chen, J, Hung, WY, Kandt, R, and Roses, AD. "Update on the molecular genetics of Duchenne muscular dystrophy." Aust Paediatr J 24 Suppl 1 (1988): 9-14. (Review)
PMID
3060079
Source
pubmed
Published In
Australian Paediatric Journal
Volume
24 Suppl 1
Publish Date
1988
Start Page
9
End Page
14

Myotonic dystrophy: update on progress to define the gene.

Using standard likelihood linkage techniques, the gene for dystrophia myotonica has been localized to the proximal long arm of chromosome 19. Several large families provided the substrate for detecting linkage of restriction fragment length polymorphisms which were developed in the laboratory from flow-sorted chromosome 19 genomic libraries. In over 500 family members from five families only a single cross-over with ApoC2 was detected. Thus a useful probe for antenatal and preclinical diagnosis is now available. Details of the strategy employed within the framework of clinical diagnosis, genetic epidemiology and recombinant DNA techniques is described.

Authors
Roses, AD; Pericak-Vance, MA; Bartlett, RJ; Yamaoka, LH; Lee, JE; Koh, J; Chen, JC; Gilbert, JR; Ross, DA; Herbstreith, MH
MLA Citation
Roses, AD, Pericak-Vance, MA, Bartlett, RJ, Yamaoka, LH, Lee, JE, Koh, J, Chen, JC, Gilbert, JR, Ross, DA, and Herbstreith, MH. "Myotonic dystrophy: update on progress to define the gene." Aust Paediatr J 24 Suppl 1 (1988): 66-69. (Review)
PMID
3060077
Source
pubmed
Published In
Australian Paediatric Journal
Volume
24 Suppl 1
Publish Date
1988
Start Page
66
End Page
69

Inherited deletion at Duchenne dystrophy locus in normal male.

Authors
Koh, J; Bartlett, RJ; Pericak-Vance, MA; Speer, MC; Yamaoka, LH; Phillips, K; Hung, WY; Ray, PN; Worton, RG; Gilbert, JR
MLA Citation
Koh, J, Bartlett, RJ, Pericak-Vance, MA, Speer, MC, Yamaoka, LH, Phillips, K, Hung, WY, Ray, PN, Worton, RG, and Gilbert, JR. "Inherited deletion at Duchenne dystrophy locus in normal male." Lancet 2.8568 (November 14, 1987): 1154-1155. (Letter)
PMID
2890056
Source
pubmed
Published In
The Lancet
Volume
2
Issue
8568
Publish Date
1987
Start Page
1154
End Page
1155

Familial inheritance of a DXS164 deletion mutation from a heterozygous female.

Restriction-fragment-length-polymorphism analysis was used to examine a female who is segregating for Duchenne muscular dystrophy (DMD) and a deletion of the DXS164 region of the X chromosome. The segregating female has no prior family history of DMD, and she has two copies of the DXS164 region in her peripheral blood lymphocytes. The following two hypotheses are proposed to explain the coincidence of the DMD phenotype and deletion of the DXS164 region in her offspring: (1) she may be a gonadal mosaic for cells with two normal X chromosomes and cells with one normal X chromosome and an X chromosome with a deletion of the DXS164 region; and (2) she may carry a familial X;autosome translocation in which the DXS164 region is deleted from one X chromosome and translocated to an autosome. The segregation of DMD and the DXS164 deletion in this family illustrates the importance of extended pedigree analysis when DXS164 deletions are used to identify female carriers of the DMD gene.

Authors
Lanman, JT; Pericak-Vance, MA; Bartlett, RJ; Chen, JC; Yamaoka, L; Koh, J; Speer, MC; Hung, WY; Roses, AD
MLA Citation
Lanman, JT, Pericak-Vance, MA, Bartlett, RJ, Chen, JC, Yamaoka, L, Koh, J, Speer, MC, Hung, WY, and Roses, AD. "Familial inheritance of a DXS164 deletion mutation from a heterozygous female." Am J Hum Genet 41.2 (August 1987): 138-144.
PMID
2887110
Source
pubmed
Published In
The American Journal of Human Genetics
Volume
41
Issue
2
Publish Date
1987
Start Page
138
End Page
144

CONSTRUCTION OF CHROMOSOME-19 RFLP PROBES FOR LINKAGE TO MYOTONIC MUSCULAR-DYSTROPHY

Authors
ROSS, DA; HERBSTREITH, M; YAMAOKA, L; GILBERT, J; PERICAKVANCE, M; HUNG, WY; KOH, J; BARTLETT, R; MOHANDAS, T; BRUNS, G; STUBBLEFIELD, E; ROSES, A
MLA Citation
ROSS, DA, HERBSTREITH, M, YAMAOKA, L, GILBERT, J, PERICAKVANCE, M, HUNG, WY, KOH, J, BARTLETT, R, MOHANDAS, T, BRUNS, G, STUBBLEFIELD, E, and ROSES, A. "CONSTRUCTION OF CHROMOSOME-19 RFLP PROBES FOR LINKAGE TO MYOTONIC MUSCULAR-DYSTROPHY." February 1987.
Source
wos-lite
Published In
Australian Paediatric Journal
Volume
23
Issue
1
Publish Date
1987
Start Page
78
End Page
78

ANALYSIS OF DMD AND BMD DNA DEFECT AT DUKE-UNIVERSITY USING REUSABLE TAQI BLOTS AND THE PROBES 754, PERT-84-10, HIP25, XJ1.1, PERT-87-42, PERT-87-1, PERT-87-8, PERT-87-15, PERT-87-30, PERT-87-41, PERT-87-J.BIR, PERT-J-66, PERT-L14 AND PERT-C7

Authors
BARTLETT, RJ; KOH, J; YAMAOKA, LH; PERICAKVANCE, MA; SPEER, MC; CHEN, JC; HUNG, WY; KANDT, RS; SIDDIQUE, T; ROSES, AD
MLA Citation
BARTLETT, RJ, KOH, J, YAMAOKA, LH, PERICAKVANCE, MA, SPEER, MC, CHEN, JC, HUNG, WY, KANDT, RS, SIDDIQUE, T, and ROSES, AD. "ANALYSIS OF DMD AND BMD DNA DEFECT AT DUKE-UNIVERSITY USING REUSABLE TAQI BLOTS AND THE PROBES 754, PERT-84-10, HIP25, XJ1.1, PERT-87-42, PERT-87-1, PERT-87-8, PERT-87-15, PERT-87-30, PERT-87-41, PERT-87-J.BIR, PERT-J-66, PERT-L14 AND PERT-C7." 1987.
Source
wos-lite
Published In
Cytogenetics and cell genetics
Volume
46
Issue
1-4
Publish Date
1987
Start Page
576
End Page
576

GENETIC-LINKAGE STUDIES OF XP21 MARKERS IN SEVERAL LARGE MULTIGENERATION DMD FAMILIES

Authors
PERICAKVANCE, MA; SPEER, M; BARTLETT, RJ; YAMAOKA, LH; KOH, J; HUNG, WY; KANDT, RS; SIDDIQUE, T; RAY, P; WORTON, R; MONACO, A; KUNKEL, L; ROSES, AD
MLA Citation
PERICAKVANCE, MA, SPEER, M, BARTLETT, RJ, YAMAOKA, LH, KOH, J, HUNG, WY, KANDT, RS, SIDDIQUE, T, RAY, P, WORTON, R, MONACO, A, KUNKEL, L, and ROSES, AD. "GENETIC-LINKAGE STUDIES OF XP21 MARKERS IN SEVERAL LARGE MULTIGENERATION DMD FAMILIES." 1987.
Source
wos-lite
Published In
Cytogenetics and cell genetics
Volume
46
Issue
1-4
Publish Date
1987
Start Page
675
End Page
675

AN INHERITED DELETION AT THE DUCHENNE DYSTROPHY LOCUS IN A NORMAL-MALE

Authors
ROSES, AD; KOH, J; BARTLETT, RJ; YAMAOKA, LH; PHILLIPS, K; PERICAKVANCE, MA; SPEER, MC; HUNG, WY; RAY, PN; WORTON, RG; GILBERT, JR; LEE, JE; SIDDIQUE, T; KANDT, RS
MLA Citation
ROSES, AD, KOH, J, BARTLETT, RJ, YAMAOKA, LH, PHILLIPS, K, PERICAKVANCE, MA, SPEER, MC, HUNG, WY, RAY, PN, WORTON, RG, GILBERT, JR, LEE, JE, SIDDIQUE, T, and KANDT, RS. "AN INHERITED DELETION AT THE DUCHENNE DYSTROPHY LOCUS IN A NORMAL-MALE." 1987.
Source
wos-lite
Published In
Cytogenetics and cell genetics
Volume
46
Issue
1-4
Publish Date
1987
Start Page
683
End Page
683
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