By searching the literature, we found that IL-6 can affect the binding of PD-L1 and PD-1 on immune cells through the IL-6/JAK1/STAT3 pathway and mediate the immune escape of tumor cells, where IL-6 up-regulates PD-L1 by the glycosylation of PD-L1 (48). Here, STAT3 is linked to neoplasm.