Piruz Shadbash - Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Center, Research Institute forGastroenterology and Liver Diseases, ShahidBeheshti University of Medical Sciences, Tehran, Iran

Merkel cell polyomavirus (MCPyV), discovered in ۲۰۰۸, is clonally integrated into about ۸۰% of Merkelcell carcinoma (MCC). MCPyV is a lately identified unique polyomavirus that is closely related tocancer. Epidemiological evidence shows that poorly controlled MCPyV infection can be a precursor toMCPyV related to MCC. A multimodal approach combining PCR and immunohistochemistry is a moresensitive and specific system to confirm the position of MCPyV between commonly used assays. Themajority of MCPyV infections are asymptomatic, but some lead to an aggressive neuroendocrine skincancer Merkel cell carcinoma (MCC). Although cases of MCC are rare, the incidence of MCC has tripledin the past two decades. MCC is more common in people over the age of ۶۰, whites, and men. Factorsthat contribute to the development of MCC include MCPyV infection, a weakened immune system, andUV exposure. There is little information about the seroepidemiology of MCPyV in the world. In virusassociatedMCC, MCPyV DNA is integrated into the tumor cell genome to maintain the expression of theMCPyV gene known as tumor antigen (T). Expression of the MCPyV T antigen promotes oncogenesis invirus-positive MCC tumors and is necessary for tumor cell growth. In contrast, virus-negative MCCsshowed a high frequency of UV-associated mutations. MCPyV-negative MCCs also have higher levels ofactivation-induced cytidine deaminase (AID) which may contribute to mutagenicity. The prognosis ofpatients with MCC positive for MCPyV is statistically better than that of patients with MCC negative forMCPyV. The aim of this study is to investigate the infection of MCPyV in MCC

Merkel cell polyomavirus, Merkel cell carcinoma, tumor antigen, oncogenesis