BMI1 and lymphoma: An in vitro cell model for investigating the role of MYC in lymphoma development was developed using LPS-activated primary murine B-cells, transduced with retroviral vectors containing doxycycline-regulated coding sequences for wild type (WT) MYC or one of two lymphoma-associated MYC mutants, in which threonine-58 is substituted with alanine (T58A) or isoleucine (T58I), together with vectors for constitutive expression of the anti-apoptotic proteins Bcl-xL, encoded by BCL2L1, and BMI1, the latter also inhibiting cellular senescence, as described previously [3].