Cobimetinib, a MEK inhibitor, decreases the number of T2-MZP Bregs, B10 Bregs, and TIM1+ Bregs in tumor-draining LNs of mice with colorectal cancer by interrupting chronic BCR signaling, while sparing the anti-tumor humoral immunity of functional B cells (216). The gene discussed is MAP2K7; the disease is neoplasm.