EGFR and breast cancer: To investigate the role of BC in LUAD progression, we grouped the LUAD dataset from TCGA by their high and low BC expression levels and performed GSEA on the gene expression signatures of these samples, and found that the gene expression signatures of BC high expression group were significantly enriched with functions related to GO: epidermal growth factor receptor signalling pathway and KEGG:_EGFR‐TKI resistance (Figure S1B).