Hypermethylation Markers in Saliva of Smokers with High Risk for Oral Potentially Malignant Disorders XC08-XC11
Dr. Pravin Raj Solomon,
Assistant Professor, Department of Biotechnology, School of Chemical and Biotechnology, SASTRA University, Thirumalaisamudram, Thanjavur-613401, Tamil Nadu, India.
Introduction: Oral Potentially Malignant Disorder (OPMD) is considered as a disease symptom which if neglected without treatment may lead to cancer. OPMDs comprise leukoplakia, erythroplakia, erytholeukoplakia (the combination of both leukoplakia and erythroplakia), Oral Submucous Fibrosis (OSMF) and lichen planus (which has a low risk of turning malignancy). It is observed that a variety of factors influence the spread of OPMDs and these includes age distribution, gender distribution and geographic distribution, amongst others.
Aim: The aim of the study is to identify the differential presence of p16 gene promoter hypermethylation in the saliva of smokers and non smokers.
Materials and Methods: A total of 52 saliva samples were collected and prepared with full acknowledgement of the subjects. DNA isolation, restriction digestion of genomic DNA, extraction of restriction enzyme digested genomic DNA, Polymerase Chain Reaction (PCR) and finally Agarose Gel Electrophoresis (AGE) were performed.
Results: 14 (70%) out of 20 samples collected from smokers were found to be methylated in p16 gene while 6 (30%) out of 20 showed no methylation. In non smokers, 29 (91%) out of 32 samples were found to be methylated. The present study shows a marginally lower rate of p16 gene hypermethylation in smokers compared to non smokers.
Conclusion: p16 gene hyper methylation is not recommended to be used as a marker for early detection of OPMDs among Malaysians. Promoter hypermethylation of p16 gene is not an early event in the prognosis of Malaysian Oral Squamous Cell Carcinoma (OSCC) patients.