Vincristine-loaded hydroxyapatite nanoparticles as a potential delivery system for bone cancer therapy

Despite advances in the development of new therapeutic agents and diagnostic imaging techniques, the 5-year survival of osteosarcoma, the most common type of bone cancer, remains practically unaltered for the last three decades at around 60%. Nanoparticle-based carriers have emerged as new class of drug delivery systems that could potentially overcome conventional chemotherapy limitations, by promoting a better drug biodistribution profile by allowing a preferential accumulation of the drug in the desired tissue, while minimising non-targeted tissue toxicity, thus resulting in an improved overall therapeutic effectiveness. Hydroxyapatite nanoparticles (HANP) are known to be biocompatible and non-immunogenic and have shown to be preferentially accumulated in bone tissues being considered a promising carrier to bone tissues. Herein, we successfully synthesised mesoporous hydroxyapatite nanoparticles with mean size of 285.32 +/- 10.29 nm and superficial area of 103.5 m(2)/g, containing significant quantities of chemotherapeutic drug vincristine. A spectrophotometric method was developed and validated aiming to quantify the vincristine (VCR)-loaded in nanoparticles. Chorioallantoic membrane assay revealed relevant anti-angiogenic activity of system, leading to accentuated reduction in the number of blood vessels in fertilised eggs. Findings presented in this paper suggested that VCR-loaded HANP has a promising future as a nanocarrier for bone cancer treatment.