TP53 and lung carcinoma: This result is in sharp contrast with our previous data obtained in wild-type p53-harboring REF52 rat fibroblasts or p53-null H1299 lung cancer cells, where phosphorylation of TopBP1 at S1159 by Akt inhibits TopBP1 from binding to Treslin during the mid- to late S phases of the cell cycle3.