Cytotoxic and Cellular Response of Doped Nb-NTO Nanoparticles Functionalized with Mentha arvensis and Mucuna pruriens Extracts on MDA-MB-231 Breast Cancer Cells.

Triple-negative breast cancer (TNBC) poses significant challenges as it lacks specific treatment approaches. In this study, we synthesized niobium-nitrogen-doped titanium dioxide (Nb-NTO) nanoparticles (NPs) functionalized with Mentha arvensis ethanolic and Mucuna pruriens methanolic extracts and evaluated their anti-cancer potential against MDA-MB-231 TNBC cells. The functionalization of doped Nb-NTO NPs with Mentha arvensis and Mucuna pruriens extract exhibited significant synergistic effects, reducing cell viability in a dose-dependent manner with enhanced cytotoxicity at lower concentrations compared to individual treatments. Microscopic analysis revealed morphological changes indicative of apoptosis and necrosis, while flow cytometry demonstrated increased apoptotic and necrotic cell populations in the combination-treated groups. These treatments also significantly reduced the secretion of pro-inflammatory cytokines IL-6 and IL-8, suggesting modulation of the inflammatory tumor microenvironment. Furthermore, the functionalized Nb-NTO NPs effectively targeted cancer stem cell (CSC) properties, inhibiting mammosphere formation and clonogenic survival and downregulating critical CSC markers, including c-Myc, OCT4, and NANOG. This study highlights the potential of Nb-NTO NPs functionalized with Mentha arvensis and Mucuna pruriens as a novel therapeutic strategy for TNBC, addressing key hallmarks of cancer, including apoptosis, inflammation, and CSC targeting. While these findings demonstrate promising in vitro anti-cancer efficacy, further in vivo validation and mechanistic studies are necessary to advance these treatments toward clinical anti-cancer applications.