MCL1 and lung cancer: B-cell lymphoma 2 (BCL-2) and myeloid cell leukemia 1 (MCL-1), the pro-survival members of BCL-2 family proteins, are upregulated in lung cancer cells and play a critical role in evading apoptosis and drug resistance (Kluck et al., 1997; Thomas et al., 2010; Xiang et al., 2018).