著者
Kosuke Shimizu Miki Takada Tomohiro Asai Kenji Irimura Kazuhiko Baba Naoto Oku
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.25, no.6, pp.783-786, 2002 (Released:2002-06-01)
参考文献数
19
被引用文献数
10 13

To enhance the therapeutic efficacy as well as to reduce the side effect, we attempted to liposomalize 4β-aminoalkyl-4′-O-demethyl-4-desoxypodophyllotoxin (TOP-53), a novel and effective topoisomerase II inhibitor. More than 90% of TOP-53 was efficiently incorporated into the liposomes composed of dipalmitoylphosphatidylcholine and cholesterol by remote-loading method. Anti-tumor activity of liposomal TOP-53 against solid tumor was examined in vivo using colon26 NL-17 carcinoma model mice. Three doses of liposomal TOP-53 (12 mg/kg/dose) showed significant tumor growth suppression (97.5% reduction determined at day 25) and the increase in life span (33%) of tumor-bearing mice. Furthermore, one mouse out of 5 was completely cured after treatment. Since similar efficacy was observed in the free TOP-53 treated group, liposomalization does not contribute much to the enhancement of therapeutic efficacy. However, a slight but measurable damage at the injection site was observed when free TOP-53 was injected, and the damage was diminished by the liposomalization. Taken together, liposomalization reduces the side effect rather than enhancing the therapeutic efficacy when TOP-53 is used.
著者
Kosuke Shimizu Miki Takada Tomohiro Asai Koichi Kuromi Kazuhiko Baba Naoto Oku
出版者
The Pharmaceutical Society of Japan
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.25, no.10, pp.1385-1387, 2002 (Released:2002-10-01)
参考文献数
19
被引用文献数
6 8

A novel anti-tumor agent, 6-[[2-(dimethylamino)ethyl]amino]-3-hydroxy-7H-indeno[2,1-c]quinolin-7-one dihydrochloride (TAS-103), effectively inhibits both topoisomerase I and II activities. To enhance anti-tumor efficacy and to reduce the side effects of the agent, liposomalization of TAS-103 was performed. TAS-103 was effectively entrapped in liposomes by a remote-loading method, and was stable at 4 °C and in the presence of 50% serum. To evaluate the anti-tumor efficacy of liposomal TAS-103, the growth inhibition against Lewis lung carcinoma cells in vitro and the therapeutic efficacy against solid tumor-bearing mice in vivo were examined. Liposomal TAS-103 showed strong cytotoxic effect against Lewis lung carcinoma cells in a dose dependent manner and effectively suppressed solid tumor growth accompanying longer survival time of tumor-bearing mice in comparison with the mice treated with free TAS-103. These results suggest that liposomal TAS-103 is useful for cancer therapy.
著者
Tomohiro Asai Naoto Oku
出版者
公益社団法人日本薬学会
雑誌
Biological and Pharmaceutical Bulletin (ISSN:09186158)
巻号頁・発行日
vol.37, no.2, pp.201-205, 2014-02-01 (Released:2014-02-01)
参考文献数
30
被引用文献数
8 14 8

Gene silencing mediated by RNA interference (RNAi) is expected to have a beneficial impact on the treatment of many diseases because of its potency, selectivity and versatility. To maximize the potential of RNAi effectors such as small interfering RNA and microRNA in clinical therapy, the development of a practical delivery system is required, especially for systemic administration. Recent studies demonstrated that chemical modification of these small RNAs and/or encapsulation of them into lipid nanoparticles is a promising strategy to achieve targeted delivery via systemic administration. In this review article, we introduce recent progress of the research on systemic delivery systems for RNAi therapeutics and consider crucial elements for the design of lipid nanoparticles as a small RNA vector.