ATP6AP1 and colorectal carcinoma: The results showed that ATP6AP1 expression levels were significantly related to most checkpoint molecules, including TNFRSF8, CD40, PDCD1, TNFRSF18, TNFRSF25, TNFRSF4, TNFRSF14, VSIR, CD276, VTCN1, and BTLA in CRC.