CDKN1A and cervical carcinoma: Expression of MCPyV LT in U2OS or cervical carcinoma C33A cells caused DNA damage and elicited phosphorylation of ATM, Chk1 (but not Chk2), H2AX, and p53, and upregulated expression of the p53 target p21Cip1/Waf1 [152,153].