HAVCR2 and melanoma: ACT and mAb treatment have been validated for their efficacy and safety in other diseases, such as melanoma [155], breast cancer [150, 156], and MS [157, 158], and recent studies have found that CD8+ tumor-infiltrating cells express PD-1 (programmed cell death protein 1) at high levels but not TIM-3 (T cell immunoglobulin domain and mucin domain-3), LAG-3 (lymphocyte activation gene-3), and ERVE4; thus, patients with metastatic ccRCC should have a better response to nivolumab [159].