To assess whether the relationship between IFITM3 and MHC-I expression is correlative or regulatory, we selected SCLC cell lines with varying levels of IFITM3 and MHC-I expression based on CCLE-SCLC RNA-seq data (Supplementary Fig. 3A) and a previous study [11]. This evidence concerns the gene IFITM3 and small cell lung carcinoma.