CD274 and cancer: High expression of PD-L1 on tumor or higher tumor mutational burden (TMB) are commonly used as biomarkers to predict the response of cancer to anti-PD-L1 or anti-PD-1 therapies [28], although anti-PD-L1 or anti-PD-1 treatment were shown to provide clinical benefit in cancer patients with high expression of PD-L1.