The Diagnostic Role of P16ink4a in Detecting High-Risk HPV16 in a Group of Syrian Nasopharyngeal Carcinoma Patients

Introduction: P16ink4a is a tumor suppressor gene, and it plays a critical role in cell cycle organizing and aging through the regulation of the Cyclin-Dependent Kinase (CDK) 4/6 and Cyclin D complexes. its inactivation corresponds with human carcinogenesis. The overexpression of p16 is considered to be a useful marker to investigate human papilloma virus (HPV) in certain cancers, but its role in nasopharyngeal cancer patients' outcomes is still unclear. Objectives: We aimed in this study to detectHPV high risk type16 expression in a sample of 89 nasopharyngeal carcinoma Syrian patients, and to detect expression of P16ink4a in the same sample. After that, we studied the correlation between the two expressions of HPV and P16ink4a and the power ofcorrelation if existed. Materials and Methods: Eighty n patients with nasopharyngeal carcinoma (NPC) treated in al Moasat universal hospital between 2010 to 2017 were chosen. To investigate the expression of P16ink4aand high-riskHPV 16 (HPVhr 16), we used immunohistochemistry staining. We evaluate the diagnostic role of p16 by discussing the expression profile of p16 in a group of NPC Syrian patients, especially those with HPVhr 16 positive expression . Results: The results of this study showed that the ratio of HPVhr 16 positive expression in 89 patients was 13.5% ,and P16ink4a positive expression was 15.7%, and there was a positive, good correlation between expression of both HPVhr and P16ink4a, so it could be an alternative aid to detect HPVhr16 in paraffin embedded formalin sections. Nonetheless more studies are needed to evaluate the importance of the lack of HPVhr 16 and P16ink4aexpression when correlate with stages of the cancer and other clinical data. Conclusions: The results of this study showed thatratio of HPVhr 16expression is 13.5 % and it is considered a weak percentage but it motivate other studies to assure the good prognosis of patients with no virus existence .Expression of P16ink4a is 15.7% and it can be a surrogate marker for HPVhr 16 in the sample of 89 NPC patients. More studies are needed to correlate prognosis with presence of P16ink4a.