Current studies have pointed out that high expression of PD-L1 in tumor cells is associated with poor prognosis in NSCLC [11, 12, 19], ovarian cancer [20] and kidney cancer [21], melanoma [22], renal cancer [21], Hodgkin lymphoma [16] and bone and soft tissue sarcoma [15, 23, 24]. Here, CD274 is linked to ovarian cancer.