Theinactivation of RB is a crucial step in the occurrence of MCC tumors.Although most negative-MCPyV MCCs transfer gene mutations/deletionsdeactivate the cell’s RB1 gene,107−109 positive MCPyV MCCsusually encode the wild-type gene RB1.65,108 However,all familiar MCC-derived LTt mutant truncation retains the RB motifbinding,90 allowing binding of them tothe factors of tumor suppressor with higher affinity.110,111 These examinations specify that the interaction between the RB andMCPyV may be essential in promoting the malignant progression of positive-MCPyVtumors. This evidence concerns the gene RB1 and Merkel cell skin cancer.