CHEK1 and cancer: Results: We found that CHK1 expression was significantly associated with low differentiation (OR=3.94, 95% CI: 2.73-5.67, P<0.05), advanced stage (OR=3.20, 95% CI: 2.30-4.44, P<0.05), vascular infiltration (OR=3.24, 95% CI: 2.18-4.82, P<0.05) and lymph node metastasis (OR=3.55, 95% CI: 2.62-4.82, P<0.05) of various cancers.