Compared with PC9ER and PC9ER shControl cells, PC9ER shMALAT-1 cells had significantly higher expression level of E-cadherin protein, while N-cadherin and ZEB-1 had significantly lower expression level, indicating that overexpression of MALAT-1 could cause EMT transformation in PC9 cells, Knockout of MALAT-1 can reverse this phenomenon, which proves that MALAT-1 can also lead to drug resistance of NSCLC EGFR-TKIs through EMT. The gene discussed is EGFR; the disease is non-small cell lung carcinoma.