Chemical aspects of controlled cisplatin release and apoptosis via Nerium oleander latex nano-carriers in breast cancer cells.

Plant-derived nano-carriers offer a sustainable and targeted strategy for cancer therapy. This study reports the synthesis and characterization of a latex-hybrid nano-carrier derived from Nerium oleander (LHNC), engineered for cisplatin (CDDP) delivery in breast cancer models. Physicochemical analyses confirmed stable, porous nanostructures with uniform particle size (∼120-150 nm), moderate surface charge (+21 mV), and high drug loading efficiency (∼85%). The system exhibited pH-responsive sustained release under acidic conditions, mimicking the tumor microenvironment. Biological evaluations demonstrated that LHNC/CDDP significantly enhanced cytotoxicity compared to free CDDP, reducing MCF-7 cell viability to ∼38% at 24 hr. Mechanistic studies revealed elevated ROS generation, mitochondrial membrane depolarization, nuclear condensation, and caspase-mediated apoptosis. Flow cytometry confirmed pronounced G2/M arrest and increased apoptotic fractions, validating the pro-apoptotic and anti-proliferative effects of the nano-carrier. Comparative analyses across luminal (MCF-7), triple-negative (MDA-MB-231), and non-tumorigenic (MCF-10A) models highlighted selective cytotoxicity toward malignant cells while sparing normal epithelial cells. Collectively, these findings position LHNC/CDDP as a promising bioinspired nanocarrier platform that integrates natural polymer advantages with chemotherapeutic precision. While the in vitro data provide compelling proof-of-concept, translational application requires rigorous toxicological evaluation, dose optimization, and in vivo validation, particularly given the bioactive cardiac glycosides in N. oleander.