CD274 and neoplasm: Our hypothesis is that the surface expressed C1q is able to inhibit and silence the oncoming tumor infiltrating cytotoxic T cells by binding to the gC1qR expressed on their surface in a manner similar to the PD-L1–PD1 checkpoint inhibition with the tumor cell expressed C1q serving the role of PD-L1 and the gC1qR on the cytotoxic T cells serving the role of PD-1.