Mentha-derived green synthesized ZnO nanoparticles potentiate methotrexate induced molecular and migratory inhibition...

Bladder cancer is characterized by high recurrence rates and limited responsiveness to conventional chemotherapy, including Methotrexate (MTX). Nanotechnology-based strategies may enhance therapeutic efficacy while reducing drug resistance. In this study, zinc oxide nanoparticles (ZnO-NPs) were green-synthesized using Mentha sp. extract and evaluated alone and in combination with MTX against T24 bladder cancer cells. The synthesized ZnO-NPs exhibited stable physicochemical properties and pronounced cytotoxic activity compared with MTX monotherapy. Combination treatment produced an additive cytotoxic effect but demonstrated enhanced mechanistic activity, including increased apoptosis, cell-cycle arrest, and DNA damage. Molecular analysis revealed significant upregulation of pro-apoptotic genes (TP53, BAX, CASP3) and suppression of the anti-apoptotic gene BCL2. In addition, the combination treatment significantly modulated TGF-β1 expression, interculture reactive oxygen species and altered cell migratory behavior. Collectively, these findings indicate that green-synthesized ZnO-NPs can potentiate MTX-induced molecular responses, supporting their potential as a nanomedicine-based adjuvant strategy for bladder cancer treatment.