PTEN and non-small cell lung carcinoma: More in details, Wang et al obtained gefitinib resistant cell line HCC827/GR through the exposure of normal HCC827 cells (NSCLC cell line with 746E-750A EGFR gene deletion) to increasingly larger concentrations of gefitinib and subsequently found that miR-214 was significantly overexpressed in HCC827/GR, also inversely correlating with the levels of PTEN expression [69].