Expression analysis of the immune checkpoint PD-1 on TILs showed a significantly increased number of PD-1+CD4+ and PD-1+CD8+ T cells in TDLNs at early stage of tumor development (T2), and of PD-1+CD8+ in tumor after 8 days (T8) of SR59230A, αPD-L1, or their combination treatment compared to control. The gene discussed is CD8A; the disease is neoplasm.