title: Microsatellite instability, promoter methylation and protein expression of the DNA mismatch repair genes in epithelial ovarian cancer.
abstract: The role of defective mismatch repair (MMR) system in ovarian carcinoma is not well defined. The purpose of the study was to determine the relationship between microsatellite instability (MSI), promoter methylation and protein expression of MMR genes in epithelial ovarian carcinoma (EOC). MSI and promoter methylation of MLH1, MSH2 and PMS2 genes were studied using PCR methods in the study cohort. A small subset of samples was used to analyze the protein expression by immunohistochemistry (IHC). MSI was observed in >60% of tumor samples and 47% of normal ovaries. MLH1 was methylated in 37.5% and 64.3% EOCs and LMP tumors. The loss of immunoexpression of MMR genes was not seen in ovarian tumors. There was no correlation between MSI, promoter methylation and protein expression of the MMR genes suggesting that each may function independently. MSI is a common event in ovarian carcinoma and may increase the clinical awareness of the subset of tumors.
authors.affiliation: Department of Biochemistry, Kidwai Memorial Institute of Oncology, Dr. M.H. Marigowda Road, Bangalore 560029 Karnataka, India. Electronic address: shilpachadaga@gmail.com.
authors.forename: Shilpa
authors.initials: S
authors.lastname: V
authors.affiliation: Department of Biochemistry, Kidwai Memorial Institute of Oncology, Dr. M.H. Marigowda Road, Bangalore 560029 Karnataka, India. Electronic address: rahulbhagat1234@gmail.com.
authors.forename: Rahul
authors.initials: R
authors.lastname: Bhagat
authors.affiliation: Department of Pathology, Kidwai Memorial Institute of Oncology, Dr. M.H. Marigowda Road, Bangalore 560029 Karnataka, India. Electronic address: prema_venka@yahoo.co.in.
authors.forename: Premalata
authors.initials: P
authors.lastname: C S
authors.affiliation: Department of Gynaec Oncology, Kidwai Memorial Institute of Oncology, Dr. M.H. Marigowda Road, Bangalore 560029 Karnataka, India. Electronic address: drpallaviram123@yahoo.co.in.
authors.forename: Pallavi
authors.initials: P
authors.lastname: V R
authors.affiliation: Department of Biochemistry, Kidwai Memorial Institute of Oncology, Dr. M.H. Marigowda Road, Bangalore 560029 Karnataka, India. Electronic address: vkrishlakshmi@gmail.com.
authors.forename: Lakshmi
authors.initials: L
authors.lastname: Krishnamoorthy
mesh_terms: D048868:Adaptor Proteins, Signal Transducing / Q000235:genetics; D000251:Adenosine Triphosphatases / Q000235:genetics; D002277:Carcinoma / Q000235:genetics*; D019175:DNA Methylation; D053843:DNA Mismatch Repair; D045643:DNA Repair Enzymes / Q000235:genetics* / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000235:genetics; D005260:Female; D042822:Genomic Instability; D006801:Humans; D018895:Microsatellite Repeats; D000070976:Mismatch Repair Endonuclease PMS2; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein / Q000235:genetics; D009687:Nuclear Proteins / Q000235:genetics; D010051:Ovarian Neoplasms / Q000235:genetics*; D011401:Promoter Regions, Genetic
chemical_list: D048868:Adaptor Proteins, Signal Transducing; D004268:DNA-Binding Proteins; C501486:MLH1 protein, human; D009687:Nuclear Proteins; D000251:Adenosine Triphosphatases; C094934:PMS2 protein, human; C497172:MSH2 protein, human; D000070976:Mismatch Repair Endonuclease PMS2; D000070957:MutL Protein Homolog 1; D051718:MutS Homolog 2 Protein; D045643:DNA Repair Enzymes
keywords: LOH; MMR; MSI; Ovarian cancer; Promoter methylation