The PPTP/C in vivo results for venetoclax are supported by the observation that the KMT2A::AFF1 fusion upregulates BCL2 gene expression (Benito et al., 2015; Godfrey et al., 2017) and that in vitro sensitivity to venetoclax for KMT2A-rearranged models, but not for other ALL models, was highly correlated with that of navitoclax (Khaw et al., 2016). This evidence concerns the gene AFF1 and acute lymphoblastic leukemia.