PRC1 and B-cell non-Hodgkin lymphoma: Finally, to determine a potential combination effect of both PRC1 and PRC2 inhibitors on reactivation of MHC-II gene expression in BAP1-deficient B cell lymphoma cells, we treated BAP1-KO A20 cells with RB-3 or/and GSK126 for 6 days, followed by Western blot and FACS analysis.