PDCD1 and melanoma: In various immunotherapy cohorts, the prognosis was commonly poor in the high‐MRS group (GSE61676: non‐small cell lung cancer, combined targeted therapy of bevacizumab plus erlotinib; GSE78220: melanoma, anti‐PD‐1; GSE135222: non‐small cell lung carcinoma, anti‐PD‐1/PD‐L1; GSE91061: melanoma, nivolumab; IMvigor210: urothelial cancer, anti‐PD‐1) (Figure 7a–e).