Furthermore, the gene mutation frequency of EML4-ALK in the resistant cells was significantly higher than that in the parent cells.    ///    "Furthermore, the gene mutation frequency of EML4-ALK in the resistant cells was significantly higher than that in the parent cells. "    ///    The echinoderm microtubule-associated protein-like 4-anaplastic lymphoma kinase (EML4-ALK) expression was evaluated by RT-PCR and Western blot.     ///    Full-length sequencing method was used to compare the EML4-ALK genes in the parent and drug-resistant cells and analyze the mechanisms of drug resistance. 