We also screened 85 NSCLC cell lines for MEK1 exon 2 mutations; one line (NCI-H1437) harbors a Q56P substitution, a known transformation-competent allele of MEK1 originally identified in rat fibroblasts, and is sensitive to treatment with AZD6244.
Somatic mutations in MEK1 gene (substitutions K57N, Q56P, D67N) were described in <1 % of non-small cell lung cancer (NSCLC) and they were more commonly reported in adenocarcinoma patients with current or former smoking status.