They drive the expression of PD-L1/PD-L2, which then bind to PD-1 on the surface of anti-T cells, reducing immune cell function.In Diffuse Large B-cell lymphoma (DLBCL), R-CHOP is still the predominant treatment regimen, with a response rate of 80%, but some patients do not benefit due to clinical resistance. The gene discussed is PDCD1; the disease is diffuse large B-cell lymphoma.