CHEK1 and familial pancreatic carcinoma: Our group and others have previously reported that GSK3β contributes to the unresponsiveness of pancreatic cancer cells to gemcitabine by impairing the DNA damage response mediated by tumor protein 53-inducible nuclear protein 1 (TP53INP1) and topoisomerase IIβ binding protein 1 (TopBP1)/ataxia telangiectasia and Rad3-related (ATR)/checkpoint kinase 1 (Chk1)[165,169,178].