CD274 and oral cavity squamous cell carcinoma: CD274 is located on chromosome 9p24.1, where amplifications and translocations are linked to upregulated expression of PD-L1 in Hodgkin's lymphoma [20, 21], small cell lung cancer (SCLC) [22], NSCLC [23], lymphoma [24], Epstein-Barr virus (EBV)-positive gastric cancer [25], and oral squamous cell carcinoma (OSCC) [26].