Also tumor cells can express PD-L2, probably in association with either a helper T (Th)2 or a Th1 response, mediated by IL-4 and IL-13 as shown in esophageal cancer [48] and with IFN-γ and glycosylation in colorectal cancer (CRC) [49]. The gene discussed is PDCD1LG2; the disease is colorectal carcinoma.