title: Vitamin E succinate induced apoptosis and enhanced chemosensitivity to paclitaxel in human bladder cancer cells in vitro and in vivo.
abstract: There have been several studies on the antitumor activities of vitamin E succinate (alpha-TOS) as complementary and alternative medicine. In the present study, we investigated the cytotoxic effect of alpha-TOS and the enhancement of chemosensitivity to paclitaxel by alpha-TOS in bladder cancer. KU-19-19 and 5637 bladder cancer cell lines were cultured in alpha-TOS and/or paclitaxel in vitro. Cell viability, flow cytometric analysis, and nuclear factor-kappa B (NF-kappaB) activity were analyzed. For in vivo therapeutic experiments, pre-established KU-19-19 tumors were treated with alpha-TOS and/or paclitaxel. In KU-19-19 and 5637 cells, the combination treatment resulted in a significantly higher level of growth inhibition, and apoptosis was significantly induced by the combination treatment. NF-kappaB was activated by paclitaxel; however, the activation of NF-kappaB was inhibited by alpha-TOS. Also, the combination treatment significantly inhibited tumor growth in mice. In the immunostaining of the tumors, apoptosis was induced and proliferation was inhibited by the combination treatment. Combination treatment of alpha-TOS and paclitaxel showed promising anticancer effects in terms of inhibiting bladder cancer cell growth and viability in vitro and in vivo. One of the potential mechanisms by which the combination therapy has synergistic cytotoxic effects against bladder cancer may be that alpha-TOS inhibits NF-kappaB induced by chemotherapeutic agents.
authors.affiliation: Department of Urology, Keio University School of Medicine, Tokyo, Japan.
authors.forename: Kunimitsu
authors.initials: K
authors.lastname: Kanai
authors.forename: Eiji
authors.initials: E
authors.lastname: Kikuchi
authors.forename: Shuji
authors.initials: S
authors.lastname: Mikami
authors.forename: Eriko
authors.initials: E
authors.lastname: Suzuki
authors.forename: Yasumitsu
authors.initials: Y
authors.lastname: Uchida
authors.forename: Kiichiro
authors.initials: K
authors.lastname: Kodaira
authors.forename: Akira
authors.initials: A
authors.lastname: Miyajima
authors.forename: Takashi
authors.initials: T
authors.lastname: Ohigashi
authors.forename: Jun
authors.initials: J
authors.lastname: Nakashima
authors.forename: Mototsugu
authors.initials: M
authors.lastname: Oya
mesh_terms: D000818:Animals; D000972:Antineoplastic Agents, Phytogenic / Q000494:pharmacology*; D000975:Antioxidants / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D004357:Drug Synergism; D006801:Humans; D051379:Mice; D008807:Mice, Inbred BALB C; D016328:NF-kappa B / Q000037:antagonists & inhibitors / Q000502:physiology; D017239:Paclitaxel / Q000494:pharmacology*; D024505:Tocopherols / Q000494:pharmacology*; D001749:Urinary Bladder Neoplasms / Q000188:drug therapy* / Q000473:pathology
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D000975:Antioxidants; D016328:NF-kappa B; D017239:Paclitaxel; D024505:Tocopherols