As a model for immortalized, yet not entirely transformed human cells, we used in vitro cultivated germinal center B cells derived from cancer-free tonsil tissue that constitutively expressed MYC and BCL2 or BCL6 and BCL2, and subsequently cultured with feeder cells secreting growth-promoting cytokines (Supplementary Fig. S2A) [35]. The gene discussed is BCL6; the disease is cancer.