It is unknown whether they express immune checkpoint inhibitory surface molecules (e.g., PD1, CTLA4, TIM3, LAG3, TIGIT, VISTA, or B7/H3), co-stimulatory molecules (e.g., CD80, CD86, OX40, ICOS, GITR, 4-1BB, or CD40), or other molecules found in the tumor microenvironment, such as IDO or TLR. Here, HAVCR2 is linked to neoplasm.