As a well-established anticancer drug, LDM exerts potent anticancer activities through the induction of apoptosis, mitotic cell death and cell cycle arrest etc., based on the dose range, treatment time and different cellular context.7 The cell cycle arrest caused by LDM in many types of cancer, including colon cancer, is mainly G2/M phase arrest because of decreased phosphorylation of Rb and increased phosphorylation of Chk1, Chk2 and Cdc25C etc.,7, 18, 19 and therefore constitutes one of major features of cellular senescence as well in this work (Figure 3). This evidence concerns the gene CHEK1 and cancer.