But what is puzzling is that COX7A1 can also up-regulate the increase the content of CD8+ T cells, which may be due to the fact that COX7A1 can up-regulate the expression of some immunosuppressive molecules or immunosuppressive cells such as Treg, thus interfering with the normal anti-tumor effect of CD8+ T cells, so it also creates conditions for the treatment of PD1/PDL1. The gene discussed is PDCD1; the disease is neoplasm.