MCL1 and breast carcinoma: Fadraciclib induces apoptosis in TNBC cell lines (Cal51 and MDA-MB-468) and the HER2-amplified HCC1954 breast cancer cell line.105 Only solid tumor cell lines with high MCL-1 expression or a high MCL-1:BCL2L1 ratio, such as A2780 (ovarian cancer) and H23 (NSCLC), are sensitive to fadraciclib.105