Effect of Metformin in Combination With Trametinib and Paclitaxel on Cell Survival and Metastasis in Melanoma Cells

Abstract

Background/aim: Despite clinical benefit from treatment with dabrafenib and trametinib in melanoma patients with BRAF mutations, half relapse within months and one-third are unresponsive to treatment. We evaluated the anticancer potential of metformin in combination with trametinib plus paclitaxel, against four melanoma cell lines.

Materials and methods: Metformin with trametinib and paclitaxel was tested for effects on cell viability, signaling molecules in MAPK and mTOR pathways, factors involved in epithelial-mesenchymal transition (EMT), and cell motility.

Results: The combination of metformin with trametinib and paclitaxel showed differential growth inhibitory effects; synergistic effects were observed in a cell line in which metformin suppresses ERK activity, whereas the combination showed antagonistic effects in a cell line with metformin-induced ERK activation. Trametinib or paclitaxel increased the expression of EMT regulators and melanoma cell motility, which were suppressed by combining metformin with trametinib and paclitaxel.

Conclusion: The combined treatment of metformin with trametinib and paclitaxel showed divergent effects on melanoma cell viability. Metformin might be useful as a potential adjuvant against cell proliferation and metastatic activity in melanoma patients.

Keywords: Metformin; combined treatment; melanoma cell; paclitaxel; trametinib.