title: Caffeine diminishes cytotoxic effects of paclitaxel on a human lung adenocarcinoma cell line.
abstract: This study was performed to investigate how caffeine modifies the cytotoxic effects of paclitaxel on a human lung carcinoma cell line. Caffeine doses up to 5mM had less effect on clonogenic survival. The cell killing effect, due to paclitaxel, increased in a dose-dependent manner up to 50 nM. For combined treatment with caffeine and paclitaxel, added caffeine reduced the cytotoxic effect of paclitaxel not only in dose-response but also in time-response curves. Caffeine combined with paclitaxel clearly suppressed cell proliferation in a dose-dependent manner. In the cell cycle analysis, caffeine alone caused early G1 accumulation, whereas paclitaxel alone caused an early increase in G2-M and a decrease in G1. As for the effect of caffeine on paclitaxel, caffeine suppressed the effect of paclitaxel on cell cycle distribution, where a dose-dependent early increase in G2-M and a decrease in G1 were not clear. We suggest that cell cycle modifying agents, such as caffeine, potentially diminish the cytotoxic activity of paclitaxel, and one should be careful when combining such agents.
authors.affiliation: Department of Radiology and Radiation Oncology, Gunma University School of Medicine, 3-39-22, Showa-machi, Maebashi, Gunma 371-8511, Japan. ykitamot@showa.gunma-u.ac.jp
authors.forename: Yoshizumi
authors.initials: Y
authors.lastname: Kitamoto
authors.forename: Hideyuki
authors.initials: H
authors.lastname: Sakurai
authors.forename: Norio
authors.initials: N
authors.lastname: Mitsuhashi
authors.forename: Tetsuo
authors.initials: T
authors.lastname: Akimoto
authors.forename: Takashi
authors.initials: T
authors.lastname: Nakano
mesh_terms: D000230:Adenocarcinoma / Q000473:pathology*; D000972:Antineoplastic Agents, Phytogenic / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D002110:Caffeine / Q000494:pharmacology*; D003864:Depression, Chemical; D004305:Dose-Response Relationship, Drug; D016193:G1 Phase / Q000187:drug effects; D016195:G2 Phase / Q000187:drug effects; D006801:Humans; D008175:Lung Neoplasms / Q000473:pathology*; D008677:Metaphase / Q000187:drug effects; D017239:Paclitaxel / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D014407:Tumor Cells, Cultured / Q000187:drug effects / Q000473:pathology; D014410:Tumor Stem Cell Assay
chemical_list: D000972:Antineoplastic Agents, Phytogenic; D002110:Caffeine; D017239:Paclitaxel