Anlotinib Exerts Anti-Cancer Effects on KRAS-Mutated Lung Cancer Cell Through Suppressing the MEK/ERK Pathway

Background: With a high frequency of 30%, KRAS mutations in patients with non-small cell lung cancer (NSCLC) often lead to their poor response to most anti-cancer therapies. As a multi-target tyrosine kinase inhibitor, Anlotinib shows clinical efficacy against several types of cancer. However, its effects on KRAS mutant NSCLC and the underlying molecular mechanisms remain unclear. Materials and Methods: Cell counting Kit-8 assay, colony formation assay, flow cytometry analysis, wound healing scratch assay, Transwell assay and xenograft mouse model were used to evaluate the anti-cancer effects of Anlotinib. The potential molecular mechanisms were determined by immunohistochemistry (IHC) and Western blotting. Results: Anlotinib inhibited proliferation of KRAS mutant lung cancer cells and induced apoptosis in vitro. In addition, the migration and invasion abilities of these cells were also decreased after treatment with Anlotinib. It significantly suppressed tumor growth in vivo and prolonged the survival of the xenograft-bearing mice, which correlated to lower expression levels of Ki67 in the tumor tissues. Mechanistically, Anlotinib downregulated MEK and ERK as well as their phosphorylated forms in the KRAS mutant lung cancer cells. Conclusion: Anlotinib inhibits the growth of KRAS mutant lung cancer cells partly via the suppression of the MEK/ERK pathway. Our findings provide novel insights into treating recalcitrant KRAS mutated NSCLC.