CD274 and neoplasm: To elucidate the underlying determinants of response and resistance, previous efforts have explored corresponding biomarkers, including PD-L1 expression levels 6, 7, tumor microenvironment gene signatures 8, 9, tumor mutation burden (TMB) 7, 8, T cell inflamed gene expression profile (GEP) 10, molecular subtypes 11, transforming growth factor β (TGFβ) signaling in fibroblasts 8, and fibroblast growth factor receptor 3 (FGFR3) alterations 12.