The cytokines, such as IFNα, IFNγ, and TNFα, were shown to increase the splicing activities of PD-L1 leading to the secretion of sPD-L1 directly by tumor cells; thus, elevated levels of sPD-L1 were found to correlate with disease progression in a study on melanoma patients [20]. Here, SPDL1 is linked to melanoma.