Methylation Status of hMLH1 Gene in Colorectal Cancer Patients in Ethnic Population of Kashmir Valley

Authors

  • Mashooq A Dar Department of Clinical Biochemistry, University Of Kashmir, Srinagar, India
  • Showkat A Bhat Faculty of Veterinary Sciences & Animal Husbandry Sher-e-Kashmir, University of Agricultural Sciences & Technology, Srinagar, India
  • Ahmad Arif Faculty of Veterinary Sciences & Animal Husbandry Sher-e-Kashmir, University of Agricultural Sciences & Technology, Srinagar, India
  • Hilal Ahmad Wani Department of Biochemistry, Govt. Medical College, Srinagar, India
  • Khalid B Dar Department of Clinical Biochemistry, University Of Kashmir, Srinagar, India
  • Rouf Maqbool Department of Clinical Biochemistry, University Of Kashmir, Srinagar, India
  • Suhail Anees Department of Clinical Biochemistry, University Of Kashmir, Srinagar, India
  • Manzoor R Mir Faculty of Veterinary Sciences & Animal Husbandry Sher-e-Kashmir, University of Agricultural Sciences & Technology, Srinagar, India

Keywords:

Colorectal cancer, hypermethylation, CpG islands, hMLH1 gene

Abstract

Background: Colorectal cancer is commonly known as bowel cancer, its development and progression is dictated by chain of alterations in genes such as tumor suppressor genes, DNA repair genes, oncogenes and others.

Method: The present work was a case control study aiming to ascertain the role of promoter methylation of CpG islands of hMLH1 gene in colorectal cancer patients among the Kashmiri population. DNA was extracted from all the samples and was modified using bisulphite modification kit. Methylation-specific polymerase chain reaction was used for the analysis of the promoter methylation status of hMLH1 gene.

Results: The epigenetic analysis revealed that unlike other high risk regions, Kashmiri population has a different promoter methylation profile of hMLH1 gene as 67.5 % of the cases showed hMLH1 promoter methylation in comparison to 15 % of the normal cases which also showed promoter methylation of hMLH1 gene. The association of promoter methylation with colorectal cancer was found to be significant (P=0.0006). Occurrence of hMLH1 promoter  methylation was found to be unequally distributed in males and females with more frequency in males than in females but the difference was not statistically significant (P=0.7635). Similarly, frequency of hMLH1 promoter methylation was found to be certainly higher in Stage III/IV (85.71%) compared to Stage I/ II (57.69%) but the difference was not statistically significant (P=0.0673).

Conclusion: The results suggest that hMLH1 aberrant promoter methylation in Kashmiri population contributes to the process of carcinogenesis in colorectal cancer and is reportedly one of the commonest epigenetic changes in the development of colorectal cancer.

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Published

2013-10-01

How to Cite

Dar, M. A., Bhat, S. A., Ahmad Arif, Hilal Ahmad Wani, Khalid B Dar, Maqbool, R., … Manzoor R Mir. (2013). Methylation Status of hMLH1 Gene in Colorectal Cancer Patients in Ethnic Population of Kashmir Valley. International Journal of Medical Research, 1(04), 1–6. Retrieved from https://ijmrinternational.in/index.php/ijmr/article/view/26

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Original Research Articles