CHEK1 and neoplasm: The linkage between reduced CHK1 functionality and glucose deprivation may provide an explanation, in part, for why the tumor microenvironment, which often contains low glucose concentrations, enhances genomic instability and mutation rates during tumorigenesis (McGranahan and Swanton, 2017; Papp‐Szabo et al., 2005; Yuan and Glazer, 1998).