Nanoparticulate drug delivery systems for cancer chemotherapy

Abstract

Deaths from lifestyle-related diseases have been decreasing because of the development of medical interventions with clear curative effects. On the other hand, the number of people with cancer is increasing. In Japan, one in every two people will have cancer, and one in three will die from it. Therefore, concern about cancer therapy is on the rise among researchers and the general public. In the past several years, knowledge of proteins that are specifically associated with various types of cancer has expanded rapidly, leading to the development of molecular-targeting drugs that could bring about revolutionary progress in cancer chemotherapy. Moreover, the technology for drug delivery systems (DDS) that carry novel agents to cancer cells efficiently is catching up. Reducing side effects and contributing to patient quality of life are expected of DDS for cancer chemotherapy. Because the technology is evolving almost daily, the newest knowledge should be monitored constantly. Therefore, the latest information on and problems with DDS that contribute to cancer chemotherapy are in presented in this Current Topics section. Six groups of world-leading scientists were invited to contribute papers updating readers on DDS research that could contribute to improved cancer chemotherapy. The first review is "Alteration of tumor microenvironment for improved delivery and intratumor distribution of nanocarriers" by Dr. Tatsuhiro Ishida and Dr. Hiroshi Kiwada (University of Tokushima). They summarized several trials that attempted to manipulate the barriers in the tumor microenvironment which hinder extravasation through the tumor vasculature and penetration of nanocarriers into solid tumors. The second is "Nanoparticle-based passive drug targeting to tumors: Considerations and implications for optimization" by Dr. Ken-ichi Ogawara and coworkers (Faculty of Pharmaceutical Sciences, Okayama University). They introduce their recent findings related to the passive drug targeting strategy for antiangiogenic therapy. "Development of liposomal anticancer drugs" was written by Dr. Kenji Hyodo as a representative of a research group at DDS Research, Eisai Co., Ltd., who addressed the process of liposomal drug product development from various viewpoints. The fourth review is "Recent advances in claudin-targeting technology" by Dr. Shotaro Nagase and coworkers (Osaka University). They describe their studies using the C-terminal fragment of Clostridium perfringens enterotoxin to target and bind claudins and discuss the efficacy of this strategy. Dr. Takuya Iwamoto (Mie University Hospital), in the review titled "Clinical application of drug delivery systems in cancer chemotherapy: Review of the efficacy and side effects of approved drugs," discusses liposomal doxorubicin and nanoparticle albumin-bound (nab)-paclitaxel, which are available clinically, including undesirable side effects. The final topic is "Application of hospital preparations for cancer treatment , and an approach toward their commercialization" by Dr. Kyohei Watanabe and...

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