In particular, metastatic melanoma and non-small-cell lung cancer are being treated with the use of PD-1 (nivolumab, pembrolizumab, and cemiplimab), PD-L1 (atezolizumab, avelumab, and durvalumab), and CTLA-4 (ipilimumab) blockers [173]. This evidence concerns the gene CTLA4 and metastatic melanoma.