PDCD1 and non-small cell lung carcinoma: In terms of NSCLC, we conducted subgroup analysis for drug targets, revealing that I2 of CTLA-4 and PD-1/PD-L1 plus CTLA-4 groups was 0 and 10.17% after grouping; however, the heterogeneity for the PD-1/PD-L1 group persisted (Fig. S2).