Inhibition of LIMK by Cofilin-1 peptidomimetics enhances actin depolymerization and reduces metastasis of non-small...

Metastasis is a major contributor to the mortality and morbidity of human non-small cell lung cancer (NSCLC), driven by actin cytoskeletal rearrangements that enhance cancer cell motility and invasiveness. Cofilin-1 (CFL-1), a key actin-binding protein regulated by LIM kinase (LIMK), controls actin turnover through phosphorylation at serine-3. However, the role of CFL-1 phosphorylation in lung cancer metastasis remains unclear. In this study, in silico analysis revealed that high LIMK/CFL-1 expression correlates with poor prognosis in lung cancer patients. Although total CFL-1 levels were elevated across NSCLC cell lines, its serine-3 phosphorylation showed a stronger association with cellular invasiveness. To therapeutically target this pathway, we developed a cofilin mimetic peptide (CMP) designed to competitively inhibit endogenous CFL-1 phosphorylation. CMP treatment selectively accumulated in LIMK-overexpressing lung cancer cells both in vitro and in vivo, and effectively suppressed actin stress fiber formation by enhancing actin depolymerization. Acting as a competitive decoy of LIMK, CMP reduced cancer cell motility and invasion, and significantly inhibited metastatic progression in orthotopic NSCLC mouse models. Importantly, CMP treatment prolonged survival without inducing systemic toxicity. These findings highlight CFL-1 phosphorylation as a critical driver of lung cancer metastasis and propose peptidomimetic inhibition of the LIMK/CFL-1 pathway as a promising therapeutic strategy for metastatic NSCLC.