CTLA4 and cancer: Immunotherapy-based combination therapies have now become the standard of care, so the use of immune checkpoint inhibitors (ICIs) to mitigate tumor-associated suppressed anti-cancer immune responses, such as programmed cell death-1 (PD-1) and cytotoxic T lymphocyte-associated antigen-4 (CTLA-4), has revolutionized the treatment of advanced ccRCC and significantly improved survival status in patients with this disease [3, 4].