The former, where certain characteristics of cancer cells/TME prevent ICIs from being efficacious and, therefore, patients do not respond to immunotherapy, can be determined by the lack of tumor antigenic mutations or defective antigen presentation, constitutive PD-L1 expression, impaired T cell tumor infiltration and function and an increased presence of immune suppressive cells within the tumor microenvironment TME [20, 21]. The gene discussed is CD274; the disease is cancer.