Moreover, the PD-L1 expression was decreased by gefitinib (1 μM and 10 μM) in two cells (Colo_150624 and 160426), but 10 μM gefitinib stimulated PD-L1 expression in gefitinib-resistant primary CRC Colo_160224 cells. The gene discussed is CD274; the disease is colorectal carcinoma.