CHEK1 and breast carcinoma: Gene expression analysis revealed that the CHK1 gene is significantly overexpressed in TNBC as compared to non-TNBC and benign lesions [104], while Verlinden et al. demonstrated that CHK1 expression is significantly higher in grade 3 breast carcinomas showing a triple negative ER−/PR−/HER-2− phenotype compared with other grade 3 tumors [100].