Nanomedicine has become an emerging platform for targeted cancer therapy, especially for solid tumors. An international collaboration between Harvard Medical School, Bucknell University, and University of Cyprus has recently established guidelines for the design of nanomedicines with optimal therapeutic effects in cancer cells, as reported in the September issue of Annals of Biomedical Engineering.
In designing nanoparticles capable of preferential delivery of anticancer agents to tumors, there has to be a balance between the penetration depth, to maximize accessibility of tumor tissues to drugs, and drug release and internalization, to ensure optimal drug uptake and efficacy. Efficient internalization of drugs entails rapid binding kinetics to prevent drugs from flowing out of the tumor before internalization occurs. On the other hand, penetration depth is limited by high binding affinities of nanoparticles to cancer cells, as rapid binding prevents the compounds from penetrating deeper into tumor tissues and distributing uniformly.
Through mathematical modelling, researchers introduced a multi-stage delivery system comprising a 20-nm primary nano-carrier, which releases 5-nm secondary nanoparticles containing drugs. They found that multi-stage nanoparticles have better therapeutic outcomes than conventional two-stage nano-carriers, which only consist of primary particles that release drugs. The smaller size of the primary particles of 20 nm also showed better penetration into tumor tissues, compared with 100-nm particles used in previous studies.
Study in Annals of Biomedical Engineering: Towards Optimal Design of Cancer Nanomedicines: Multi-stage Nanoparticles for the Treatment of Solid Tumors…