Dual-loaded niosome-dendrimer nanoplatform enhances Tirapazamine delivery to hypoxic breast cancer cells.

Breast cancer (BC) is one of the most common cancers in women, requiring comprehensive treatment strategies to reduce disease burden and costs. In this study, we developed an innovative dual nanoparticle system based on niosome containing PAMAM/Tirapazamine (N@P/T), and studied its efficacy combining in silico and experimental validation. Molecular docking and protein-protein interaction network analysis identified HIF1A as a central target for Tirapazamine (TPZ), revealing multiple high-confidence binding sites and interactions with key cancer-related pathways. Our synthesized N@P/T system using the thin film hydration method showed a size of ~ 200 nm, a zeta potential of - 4 mV, and a spherical morphology. Further, MTT results demonstrated that N@P/T significantly enhances anti-cancer effects compared to P/T and free TPZ, exhibiting the lowest IC50 value of 14.14 μM, which indicates superior cytotoxic efficiency compared to P/T (IC50 = 71.37 μM) and free TPZ (IC50 = 143.3 μM). Annexin-V FITC/Pi double staining showed enhanced apoptosis-promoting effects of P/T (44.28%) and N@P/T (65.33%), partially via affecting expression levels of BCL2, caspase3 and BAX. The uptake assay revealed substantial internalization of N@P/T over 90% by 4h, while real-time PCR validated the HIF1A as a target for TPZ under hypoxia-stimulated condition. Furthermore, the spheroid size test demonstrates the superior penetration capability of N@P/T, leading to significant alterations in tumor spheroid size and morphology. Our integrated computational and experimental approach demonstrates that N@P/T effectively targets hypoxic cancer cells through specific molecular interactions, offering a promising strategy for BC treatment.