Researchers conducted gene expression profile analysis of melanoma patients treated with pembrolizumab, and identified an IFN-γ-related signature as a prognostic marker by comparing responders and non-responders, further confirming its association with PFS and ORR in head and neck squamous cell carcinoma (HNSCC) and gastric cancer (GC) (87). The gene discussed is IFNG; the disease is head and neck squamous cell carcinoma.