Although several Mcl-1 inhibitors have been developed and exhibited promising anti-tumor efficacy in pre-clinical leukemia or solid tumor animal models (Ramsey et al. 2018; Dengler et al. 2020; Kotschy et al. 2016), there is still a lack of Mcl-1 inhibitors approved for clinical use. The gene discussed is MCL1; the disease is leukemia.