CD80 and neoplasm: Therefore, immune checkpoint inhibitors (ICIs), which involve antibodies and target different proteins of the immune checkpoint pathway, such as CTLA-4, CD86/B7-2, CD80/B7-1, PD-1, PD-L1/B7-H1 and PD-L2/B7-DC, can activate the tumour immune system and are now considered a potential treatment strategy for mRCC [6].