Using the YUMM1.7 melanoma mouse model (12), we have previously demonstrated that tumoral TLS polymerases are transiently elevated following intratumoral delivery of the DNA damaging chemotherapeutic drug, cisplatin (13) and that the anti-CTLA-4/anti-PD-1 ICB regimen (14, 15), given in conjunction with intratumoral cisplatin, leads to complete tumor regression in the mouse (13). The gene discussed is CTLA4; the disease is melanoma.