Since the signature miRNA are differentially expressed among cell lines, the majority of their promoters contain putative SBEs, and the known dual behaviour of TGFβ activity on gene expression, we hypothesized that the canonical TGFβ signalling pathway likely controls in the opposing expression levels of signature miRNA between erlotinib-resistant and - sensitive NSCLC lines. This evidence concerns the gene TGFB1 and non-small cell lung carcinoma.