Enhancing breast cancer treatment with Bauhinia variegata capped copper oxide nanoparticles: A sustainable chemistry approach

• Confirmation of sustainably synthesized copper oxide nanoparticles of Bauhinia variegata (BVCuONPs) with highest UV absorption peak at 353.7nm. • FE-SEM and TEM analysis exhibited uniformly dispersed BVCuONPs with 45nm- 47.12nm average particle size. • The anti-proliferative impact of BVCuONPs was investigated on MCF-7 (IC50-63.31µg/ml) and MDA-MB-231(IC50-27.68 µg/ml). • BVCuONPs depolarized the mitochondrial membrane and cell cycle arrest in MDA MB 231 cells at the G2/M phase. • Reduction in vascularization by 53.736 % with BVCuONPs in the chorioallantoic membrane (CAM) model. • The qRT-PCR analysis showed a markedly elevated p53 expression level, which strongly supports the MTT, cell cycle arrest, and MMP assay results. • Sustainable and green synthesized BVCuONP develops greater promising possibilities for targeting therapeutically detrimental malignancies. Breast cancer remains one of the leading causes of death among Asian females, highlighting an urgent quest for effective long-term treatment strategies. The present research work deals with sustainable synthesis, characterization, and evaluation of Bauhinia variegata L. capped copper oxide nanoparticles (BVCuONPs). Bauhinia variegata L. aqueous leaf extract was used as an encapsulating and reducing agent in copper oxide nanoparticle synthesis. The fabricated nanoparticles were examined with Transmission Electron Microscopy, Field Emission Scanning Electron Microscopy, and UV-visible absorption spectroscopy. MCF-7, MDA-MB-231 and MCF-10A cells were used to evaluate the anti-proliferative potential and selectivity of the nanoparticles. In addition, the chick chorioallantoic membrane assay was used to evaluate the anti-angiogenic characteristics. Cell migration assay and mitochondrial membrane potential assay were also performed along with gene expression analysis. Spectroscopic investigation confirmed the fabrication of copper oxide nanoparticles with the highest absorption peak at 353 nm. Field Emission Scanning Electron Microscopy and Transmission Electron microscopy showed uniformly distributed nanoparticles with sizes ranging from 31–63 nm and an average of 47 nm. BVCuONPs caused cell cycle arrest at the G1 and G2/M phase, promoted mitochondrial membrane depolarisation, and exhibited potent anti-proliferative effects against MCF-7 and MDA-MB-231 cell lines. The nanoparticles significantly inhibited cellular migration (42.38 %) and reduced vascularization (53.73 %), indicating anti-angiogenic potential. Furthermore, these nanoparticles generated reactive oxygen species (ROS) leading to DNA damage and trigger the stress response pathway by activating p53. These green-synthesized copper nanoparticles demonstrated strong potential as targeted anticancer agents by activating p53 and triggering apoptosis. Their efficacy further encourages exploration in combination therapies, which should be validated through systematic in-vivo studies.