While not contributes to the potentiated anti-tumor immunity, the up-regulation of tumor PD-L1 under ER stress could provide the molecular basis for the employment of anti-PD-1 antibody to block the interaction between PD-L1 and PD-1, and high PD-L1 expression is regarded as a promising biomarker for predicting better treatment outcome of immunotherapy [67]. The gene discussed is CD274; the disease is neoplasm.