MEF2B and diffuse large B-cell lymphoma: Although an early study found that some MEF2B mutations increased the expression of a BCL6 reporter gene in HEK293 cells by disrupting interactions with the co-repressor CABIN1 [55], a subsequent study found that MEF2B mutations tended to decrease endogenous MEF2B target gene activation in both HEK293 and DLBCL cells [70].