pH-Responsive Chitosan-Adorned Niosome Nanocarriers for Co-Delivery of Drugs for Breast Cancer Therapy

Breast cancer incidence has increased in recent decades. In the present study, an optimum formulation of chitosan (CS)-adorned niosome-based nanocarriers for co-delivery of doxorubicin (DOX) and vincristine (VIN) was developed for the treatment of breast cancer to reduce drug doses and overcome multidrug resistance. The three-level Box–Behnken method was utilized to optimize the particles in terms of size, polydispersity index (PDI), entrapment efficacy (EE (%)), and percent of drug release (%). The release rate of two drugs from CS-adorned nanoparticles (DOX+VIN/Nio/CS) in acidic and physiological pH is less than uncoated niosome (DOX+VIN/Nio). In addition, acidic pH increases the release rate of drugs from these formulations. The size, polydispersity index, and entrapment efficacy of nanoparticles were more stable at 4 °C compared to 25 °C. MTT assay showed that the IC50 of DOX+VIN/Nio/CS is the lowest value between all fabricated formulations. We evaluated the cancer metastasis and migration (MMP2, MMP9) and transcriptional targets for the tumor suppressor protein (Bax, Bcl2) that induces cell cycle arrest or apoptosis in response to DNA. Bax gene was highly expressed, while the Bcl2, MMP2, and MMP9 genes decreased in DOX+VIN/Nio/CS compared to control, free forms of DOX, VIN, DOX+VIN, and DOX+VIN/Nio. DOX+VIN/Nio/CS inhibited cell migration and increased apoptosis, cell uptake, and endocytosis in human SKBR3 breast cancer cells compared to DOX, VIN, DOX+VIN. These in vitro data are promising to treat breast cancer with advanced pH-responsive drug release nanoformulations.