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Sarver AL, Mills LJ, Makielski KM, Temiz NA, Wang J, Spector LG, Subramanian S, Modiano JF. Distinct mechanisms of PTEN inactivation in dogs and humans highlight convergent molecular events that drive cell division in the pathogenesis of osteosarcoma. Cancer Genet 2023; 276-277:1-11. [PMID: 37267683 DOI: 10.1016/j.cancergen.2023.05.001] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2022] [Revised: 03/02/2023] [Accepted: 05/19/2023] [Indexed: 06/04/2023]
Abstract
A hallmark of osteosarcoma in both human and canine tumors is somatic fragmentation and rearrangement of chromosome structure which leads to recurrent increases and decreases in DNA copy number. The PTEN gene has been implicated as an important tumor suppressor in osteosarcoma via forward genetic screens. Here, we analyzed copy number changes, promoter methylation and transcriptomes to better understand the role of PTEN in canine and human osteosarcoma. Reduction in PTEN copy number was observed in 23 of 95 (25%) of the canine tumors examined leading to corresponding decreases in PTEN transcript levels from RNA-Seq samples. Unexpectedly, canine tumors with an intact PTEN locus had higher levels of PTEN transcripts than human tumors. This variation in transcript abundance was used to evaluate the role of PTEN in osteosarcoma biology. Decreased PTEN copy number and transcript level was observed in - and likely an important driver of - increases in cell cycle transcripts in four independent canine transcriptional datasets. In human osteosarcoma, homozygous copy number loss was not observed, instead increased methylation of the PTEN promoter was associated with increased cell cycle transcripts. Somatic modification of PTEN, either by homozygous deletion in dogs or by promoter methylation in humans, is clinically relevant to osteosarcoma, because the cell cycle related transcripts are associated with patient outcomes. The PTEN gene is part of a syntenic rearrangement unique to the canine genome, making it susceptible to somatic loss of both copies of distal chromosome 26 which also includes the FAS death receptor. SIGNIFICANCE STATEMENT: PTEN function is abrogated by different mechanisms in canine and human osteosarcoma tumors leading to uncontrolled cell cycling. Somatic loss of this canine specific syntenic region may help explain why the canine genome appears to be uniquely susceptible to osteosarcoma. Syntenic arrangement, in the context of copy number change, may lead to synergistic interactions that in turn modify species specific cancer risk. Comparative models of tumorigenesis may utilize different driver mechanisms.
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Affiliation(s)
- Aaron L Sarver
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Institute for Health Informatics, University of Minnesota, Minneapolis, MN 55455, USA; Animal Cancer Care and Research Program, University of Minnesota, St. Paul, MN 55108, USA.
| | - Lauren J Mills
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN 55455, USA
| | - Kelly M Makielski
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Animal Cancer Care and Research Program, University of Minnesota, St. Paul, MN 55108, USA; Department of Veterinary Clinical Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN 55108, USA
| | - Nuri A Temiz
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Institute for Health Informatics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Jinhua Wang
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Institute for Health Informatics, University of Minnesota, Minneapolis, MN 55455, USA
| | - Logan G Spector
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Department of Pediatrics, University of Minnesota Medical School, Minneapolis, MN 55455, USA; Animal Cancer Care and Research Program, University of Minnesota, St. Paul, MN 55108, USA
| | - Subbaya Subramanian
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Animal Cancer Care and Research Program, University of Minnesota, St. Paul, MN 55108, USA; Department of Surgery, University of Minnesota School of Medicine, Minneapolis, MN 55455, USA
| | - Jaime F Modiano
- Masonic Cancer Center, University of Minnesota, Minneapolis, MN 55455, USA; Animal Cancer Care and Research Program, University of Minnesota, St. Paul, MN 55108, USA; Department of Veterinary Clinical Sciences, University of Minnesota College of Veterinary Medicine, St. Paul, MN 55108, USA; Center for Immunology, University of Minnesota, Minneapolis, MN 55455, USA; Stem Cell Institute, University of Minnesota, Minneapolis, MN 55455, USA; Center for Engineering and Medicine, University of Minnesota, Minneapolis, MN 55455, USA; Department of Laboratory Medicine and Pathology, University of Minnesota Medical School, Minneapolis, MN 55455, USA
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Balinisteanu I, Panzaru MC, Caba L, Ungureanu MC, Florea A, Grigore AM, Gorduza EV. Cancer Predisposition Syndromes and Thyroid Cancer: Keys for a Short Two-Way Street. Biomedicines 2023; 11:2143. [PMID: 37626640 PMCID: PMC10452453 DOI: 10.3390/biomedicines11082143] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/20/2023] [Accepted: 07/26/2023] [Indexed: 08/27/2023] Open
Abstract
Cancer predisposition syndromes are entities determined especially by germinal pathogenic variants, with most of them autosomal dominantly inherited. The risk of a form of cancer is variable throughout life and affects various organs, including the thyroid. Knowing the heterogeneous clinical picture and the existing genotype-phenotype correlations in some forms of thyroid cancer associated with these syndromes is important for adequate and early management of patients and families. This review synthesizes the current knowledge on genes and proteins involved in cancer predisposition syndromes with thyroid cancer and the phenomena of heterogeneity (locus, allelic, mutational, and clinical).
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Affiliation(s)
- Ioana Balinisteanu
- Endocrinology Department, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (I.B.); (M.-C.U.)
- Endocrinology Department, “Sf. Spiridon” Hospital, 700106 Iasi, Romania
| | - Monica-Cristina Panzaru
- Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (A.F.); (E.V.G.)
| | - Lavinia Caba
- Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (A.F.); (E.V.G.)
| | - Maria-Christina Ungureanu
- Endocrinology Department, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (I.B.); (M.-C.U.)
- Endocrinology Department, “Sf. Spiridon” Hospital, 700106 Iasi, Romania
| | - Andreea Florea
- Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (A.F.); (E.V.G.)
| | - Ana Maria Grigore
- Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (A.F.); (E.V.G.)
| | - Eusebiu Vlad Gorduza
- Department of Medical Genetics, Faculty of Medicine, “Grigore T. Popa” University of Medicine and Pharmacy, 700115 Iasi, Romania; (A.F.); (E.V.G.)
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Gingival Overgrowths Revealing PTEN Hamartoma Tumor Syndrome: Report of Novel PTEN Pathogenic Variants. Biomedicines 2022; 11:biomedicines11010081. [PMID: 36672590 PMCID: PMC9855721 DOI: 10.3390/biomedicines11010081] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2022] [Revised: 12/23/2022] [Accepted: 12/23/2022] [Indexed: 12/30/2022] Open
Abstract
PTEN hamartoma tumor syndrome (PHTS), is a spectrum of disorders caused by mutations of PTEN, in which non-cancerous growths, called hamartomas, develop in different areas of the body, often including the oral mucosa. PHTS also implies a recognized increased risk of malignancies, as PTEN is a tumor suppressor gene capable of inhibiting progression of several cancers. One of the main and most common clinical manifestation of PHTS are gingival overgrowths presenting as warty lumps. The current study describes patients with gingival or mucosal enlargements leading to the diagnosis of PHTS associated to novel PTEN pathogenic variants. Patients referred to us for gingival lumps suggestive of PHTS associated overgrowths were submitted to genetic analysis in the PTEN gene. Two related and two unrelated patients were investigated. PTEN novel pathogenic variant was found in all of them. Two patients also fulfilled diagnostic criteria of Cowden syndrome (CS). Mucocutaneous lesions, and particularly diffuse gingival overgrowths, are both early and major clinical signs revealing a potential diagnosis of PHTS. Further genetic and clinical assessments are needed in order to confirm and clarify the diagnosis within the PHTS spectrum, including, among others, the CS. A correct interpretation of oral clinical features potentially associated to PHTS is mandatory for diagnosis and a surgical approach can be useful just in case of impairment of periodontal health or for aesthetic needs. The increased risk of malignancies associated to PHTS makes a correct diagnosis pivotal to set up an appropriate lifelong surveillance, aiming at secondary cancer prevention.
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Pena-Couso L, Ercibengoa M, Mercadillo F, Gómez-Sánchez D, Inglada-Pérez L, Santos M, Lanillos J, Gutiérrez-Abad D, Hernández A, Carbonell P, Letón R, Robledo M, Rodríguez-Antona C, Perea J, Urioste M, Alonso MÁ, Andrés R, Arévalo S, del Mar Arias M, Balmaña J, Beristain E, Blanco I, Boronat M, Brunet J, Cózar MV, del Campo M, Díaz A, Gabau E, Barcina MJ, González M, Guitart M, Hernán I, Hernández HS, Hernando S, Lacambra C, Lasa A, Lastra E, Llort G, del Rosario Marín M, Marrupe D, Martínez F, Martínez V, Martorell L, Orera M, Pedrinaci S, Pérez P, Pineda M, Plasencia AM, Cajal TRY, Robles L, Rodà D, Rodríguez N, Rosell J, Sáez R, Salvat M, Sánchez A, Santana A, Soto JL, Toll A, Tuneu A, Vázquez C. Considerations on diagnosis and surveillance measures of PTEN hamartoma tumor syndrome: clinical and genetic study in a series of Spanish patients. Orphanet J Rare Dis 2022; 17:85. [PMID: 35227301 PMCID: PMC8886852 DOI: 10.1186/s13023-021-02079-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2021] [Accepted: 10/10/2021] [Indexed: 11/10/2022] Open
Abstract
Background The limited knowledge about the PTEN hamartoma tumor syndrome (PHTS) makes its diagnosis a challenging task. We aimed to define the clinical and genetic characteristics of this syndrome in the Spanish population and to identify new genes potentially associated with the disease. Results We reviewed the clinical data collected through a specific questionnaire in a series of 145 Spanish patients with a phenotypic features compatible with PHTS and performed molecular characterization through several approaches including next generation sequencing and whole exome sequencing (WES). Macrocephaly, mucocutaneous lesions, gastrointestinal polyposis and obesity are prevalent phenotypic features in PHTS and help predict the presence of a PTEN germline variant in our population. We also find that PHTS patients are at risk to develop cancer in childhood or adolescence. Furthermore, we observe a high frequency of variants in exon 1 of PTEN, which are associated with renal cancer and overexpression of KLLN and PTEN. Moreover, WES revealed variants in genes like NEDD4 that merit further research. Conclusions This study expands previously reported findings in other PHTS population studies and makes new contributions regarding clinical and molecular aspects of PHTS, which are useful for translation to the clinic and for new research lines. Supplementary Information The online version contains supplementary material available at 10.1186/s13023-021-02079-7.
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Kim JC, Bodmer WF. Genomic landscape of colorectal carcinogenesis. J Cancer Res Clin Oncol 2022; 148:533-545. [DOI: 10.1007/s00432-021-03888-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 12/11/2021] [Indexed: 12/19/2022]
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Wallander K, Thonberg H, Nilsson D, Tham E. Massive parallel sequencing in individuals with multiple primary tumours reveals the benefit of re-analysis. Hered Cancer Clin Pract 2021; 19:46. [PMID: 34711244 PMCID: PMC8555269 DOI: 10.1186/s13053-021-00203-z] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2021] [Accepted: 10/12/2021] [Indexed: 11/17/2022] Open
Abstract
Multiple primary cancers, defined as three or more primary tumours, are rare, and there are few genetic studies concerning them. There is a need for increased knowledge on the heritability of multiple primary cancers and genotype-phenotype correlations. We have performed whole-genome/exome sequencing (WGS/WES) in ten individuals with three or more primary tumours, with no previous findings on standard clinical genetic investigations. In one individual with a clinical diagnosis of MEN1, a likely pathogenic cryptic splice site variant was detected in the MEN1 gene. The variant (c.654C > A) is synonymous but we showed in a cDNA analysis that it affects splicing and leads to a frameshift, with the theoretical new amino acid sequence p.(Gly219Glufs*13). In one individual with metachronous colorectal cancers, ovarian cancer, endometrial cancer and chronic lymphocytic leukaemia, we found a likely pathogenic variant in the MLH1 gene (c.27G > A), and two risk factor variants in the genes CHEK2 and HOXB13. The MLH1 variant is synonymous but has previously been shown to be associated to constitutional low-grade hypermethylation of the MLH1 promoter, and segregates with disease in families with colorectal and endometrial cancer. No pathogenic single nucleotide or structural variants were detected in the remaining eight individuals in the study. The pathogenic variants found by WGS/WES were in genes already sequenced by Sanger sequencing and WES in the clinic, without any findings. We conclude that, in individuals with an unequivocal clinical diagnosis of a specific hereditary cancer syndrome, where standard clinical testing failed to detect a causative variant, re-analysis may lead to a diagnosis.
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Affiliation(s)
- Karin Wallander
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden.
- Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden.
| | - Håkan Thonberg
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Daniel Nilsson
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
| | - Emma Tham
- Department of Molecular Medicine and Surgery, Karolinska Institutet, Stockholm, Sweden
- Department of Clinical Genetics, Karolinska University Hospital, Stockholm, Sweden
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Chen R, Wang M, Fu S, Cao F, Duan P, Lu J. MicroRNA-204 may participate in the pathogenesis of hypoxic-ischemic encephalopathy through targeting KLLN. Exp Ther Med 2019; 18:3299-3306. [PMID: 31602202 PMCID: PMC6777329 DOI: 10.3892/etm.2019.7936] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 11/14/2018] [Indexed: 01/04/2023] Open
Abstract
Hypoxic-ischemic encephalopathy (HIE) is a common neonatal disease that can lead to high neonatal mortality rates. Previous studies have indicated that microRNAs (miRs) may be involved in the pathogenesis of HIE; however, the specific mechanisms underlying their involvement require further investigation. The aim of the present study was to investigate the roles of miR-204 and its target gene killin p53 regulated DNA replication inhibitor (KLLN) in HIE using rat HIE models. Brain injury was induced by surgery and incubation of hypoxic incubator brain using 10-day-old pup rats. On day 3, rats were sacrificed, and the infarct size of the brain was determined using a tetrazolium chloride assay. Terminal deoxynucleotidyl transferase UTP nick-end labeling staining was performed to detect the cell death rate in the brain tissue. Following this, the brain tissues were collected, and reverse transcription-quantitative polymerase chain reaction, western blot analysis and immunohistochemistry assays were performed to examine the expression levels of miR-204 and KLLN. Furthermore, neurons were cultured and transfected with miR-204 inhibitors or mimics, and the effect of miR-204 on the proliferation and apoptosis of neurons was examined using MTT and flow cytometric assays. Finally, a dual-luciferase reporter assay was performed to confirm whether KLLN is a direct target of miR-204. The expression of miR-204 was significantly downregulated and the expression of KLLN was significantly increased in the brain tissue of HIE rats (P<0.001). In addition, the transfection with miR-204 inhibitors significantly decreased the proliferation rates and significantly increased the apoptosis rate of neurons; however, transfection with miR-204 mimics prompted the opposite results. The dual-luciferase reporter assay also confirmed that KLLN is a direct target of miR-204. Taken together, the results of the present study demonstrated that miR-204 was downregulated in HIE and that miR-204 may serve important roles in the pathogenesis of HIE through targeting KLLN.
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Affiliation(s)
- Ronglin Chen
- Department of Critical Care Medicine, Longgang District Central Hospital, Shenzhen, Guangdong 518116, P.R. China
| | - Meixia Wang
- Department of Critical Care Medicine, Longgang District Central Hospital, Shenzhen, Guangdong 518116, P.R. China
| | - Shaopin Fu
- Department of Critical Care Medicine, Longgang District Central Hospital, Shenzhen, Guangdong 518116, P.R. China
| | - Feng Cao
- Department of Critical Care Medicine, Longgang District Central Hospital, Shenzhen, Guangdong 518116, P.R. China
| | - Pengkai Duan
- Department of Intensive Care Unit, Affiliated General Hospital of Guangzhou Military Command of Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
| | - Jiefu Lu
- Department of Intensive Care Unit, Affiliated General Hospital of Guangzhou Military Command of Southern Medical University, Guangzhou, Guangdong 510515, P.R. China
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A pathogenic role for germline PTEN variants which accumulate into the nucleus. Eur J Hum Genet 2018; 26:1180-1187. [PMID: 29706633 DOI: 10.1038/s41431-018-0155-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Revised: 03/27/2018] [Accepted: 03/30/2018] [Indexed: 11/08/2022] Open
Abstract
The PTEN gene encodes a master regulator protein that exerts essential functions both in the cytoplasm and in the nucleus. PTEN is mutated in the germline of both patients with heterogeneous tumor syndromic diseases, categorized as PTEN hamartoma tumor syndrome (PHTS), and a group affected with autism spectrum disorders (ASD). Previous studies have unveiled the functional heterogeneity of PTEN variants found in both patient cohorts, making functional studies necessary to provide mechanistic insights related to their pathogenicity. Here, we have functionally characterized a PTEN missense variant [c.49C>G; p.(Gln17Glu); Q17E] associated to both PHTS and ASD patients. The PTEN Q17E variant displayed partially reduced PIP3-catalytic activity and normal stability in cells, as shown using S. cerevisiae and mammalian cell experimental models. Remarkably, PTEN Q17E accumulated in the nucleus, in a process involving the PTEN N-terminal nuclear localization sequence. The analysis of additional germline-associated PTEN N-terminal variants illustrated the existence of a PTEN N-terminal region whose targeting in disease causes PTEN nuclear accumulation, in parallel with defects in PIP3-catalytic activity in cells. Our findings highlight the frequent occurrence of PTEN gene mutations targeting PTEN N-terminus whose pathogenicity may be related, at least in part, with the retention of PTEN in the nucleus. This could be important for the implementation of precision therapies for patients with alterations in the PTEN pathway.
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Guilmette J, Nosé V. Hereditary and familial thyroid tumours. Histopathology 2017; 72:70-81. [DOI: 10.1111/his.13373] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2017] [Revised: 08/22/2017] [Accepted: 08/24/2017] [Indexed: 01/16/2023]
Affiliation(s)
| | - Vania Nosé
- Massachusetts General Hospital; Boston MA USA
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Upregulated microRNA-224 promotes ovarian cancer cell proliferation by targeting KLLN. In Vitro Cell Dev Biol Anim 2016; 53:149-156. [PMID: 27663866 DOI: 10.1007/s11626-016-0093-2] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2016] [Accepted: 08/29/2016] [Indexed: 10/21/2022]
Abstract
Human epithelial ovarian cancer is a complex disease, with low 5-yr survival rate largely due to the terminal stage at diagnosis in most patients. MicroRNAs play critical roles during epithelial ovarian cancer progression in vivo and have also been shown to regulate characteristic of ovarian cancer cell line in vitro. Alterative microRNA-224 (microRNA-224) expression affects human epithelial ovarian cancer cell survival, apoptosis, and metastasis. However, people know little about the effects of microRNA-224 on epithelial ovarian cancer cell proliferation. In the current study, we found that the microRNA-224 expression level of human syngeneic epithelial ovarian cancer cells HO8910 (low metastatic ability) was lower than that of HO8910PM (high metastatic ability). Furthermore, microRNA-224 was confirmed to target KLLN in HO8910 and HO8910PM. The known KLLN downstream target cyclin A was regulated by microRNA-224 in HO8910 and HO8910PM. In addition, overexpression of microRNA-224 enhanced the proliferation abilities of HO8910 and knockdown of microRNA-224 suppressed the proliferation abilities of HO8910PM by KLLN-cyclin A pathway. Our results provide new data about microRNAs and their targets involved in proliferation of epithelial ovarian cancer cells by modulating the downstream signaling.
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Association of specific PTEN/10q haplotypes with endometrial cancer phenotypes in African-American and European American women. Gynecol Oncol 2015; 138:434-40. [PMID: 26026735 DOI: 10.1016/j.ygyno.2015.05.024] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/01/2015] [Accepted: 05/22/2015] [Indexed: 12/12/2022]
Abstract
OBJECTIVE Endometrial carcinoma (EC), the most common gynecologic malignancy in the United States, affects European American (EA) women more frequently than African-American (AA) women. Yet, AA women are more likely to die from EC. Proposed etiologies for this racial disparity, such as socioeconomic status, aggressive, non-endometrioid tumor histology, and comorbid conditions, do not account for the entire disparity experienced by AA women, suggesting an unexplored genetic component. Germline mutations in PTEN cause Cowden syndrome (CS), which increases lifetime risk of endometrial cancer. In addition, somatic PTEN silencing is one of the most common initiating events in sporadic EC. Therefore, we hypothesized that specific PTEN haplotypes in the AA population may directly predispose AA women to unfavorable tumor characteristics when diagnosed with EC. METHODS We conducted a case-control association study of germline variations in and around the PTEN/10q region between 53 EA and 51 AA EC cases and ethnic controls. RESULTS Eighteen tag SNPs with minor allele frequency ≥0.1, were genotyped and used to reconstruct haplotypes. Forty-eight ancestry informative markers were genotyped control for population stratification. Two haplotypes were overrepresented in AA, and there was a trend towards tumors with higher stage and grade in patients with these haplotypes. One haplotype was overrepresented in the EA population with a trend towards more endometrioid tumors. CONCLUSIONS We show that specific PTEN/10q haplotypes are significantly different between EA and AA individuals (p≤0.02), and specific haplotypes may increase the risk of unfavorable tumor phenotypes in AA women diagnosed with EC.
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