They also found that upregulation of miR-200c increased gefitinib sensitivity in the EGFR non-mutation NSCLC cell line A549, but not in H1975 cells, which exhibit EGFR-T790M-mutation, whereas blocking the expression of miR-200c in PC9 cells, which are NSCLC cells that have both EGFR-L858R-mutation and a deletional mutation (E746-A750) in EGFR exon 19, was associated with slight resistance to gefitinib. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.