Prior deglycosylation of cancer tissues altered the PD-L1 status from negative to positive in approximately 16% of tumors in responders to anti-PD-L1 therapy, and the PD-L1 expression scores were significantly correlated to overall survival (OS) after but not before the deglycosylation (P = 0.005 and P = 0.29, respectively) in a study of 95 patients who received anti-PD-L1 therapy12. The gene discussed is CD274; the disease is cancer.