CX3CL1 and cancer: Some immune checkpoint stimulatory genes are positively correlated, while some are negatively correlated with the high-risk group in various cancer types; most immune checkpoint stimulatory genes in LGG, LIHC, and BLCA are elevated; however, BTN3A1, CX3CL1, ENTPD1, HMGB1, and TLR4 in KIRC; CD40LG, IL2, and TNFRSF14 in LUAD; and CD40LG and SELP in PAAD are significantly reduced in the high-risk group (Figure 7D).