title: Restoration of IGFBP-rP1 increases radiosensitivity and chemosensitivity in hormone-refractory human prostate cancer.
abstract: We previously reported the tumor-suppressive activity of insulin-like growth factor binding protein-related protein 1 (IGFBP-rP1) through induction of apoptosis in human prostate cancer cells. The aim of this study was to investigate the effects of IGFBP-rP1 for radiosensitivity and chemosensitivity in hormone-refractory human prostate PC-3 cancer cells. Five assays were performed using PC-3 cells transfected with IGFBP-rP1 (PC-3rP1) and control cells transfected with an empty vector (PC-3N): PC-3rP1 and PC-3N were compared by clonogenic survival assay, cell cycle analysis and apoptotic assay for radiosensitivity. The number of colonies of PC-3rP1 cells significantly decreased after 4 and 8 Gy of irradiation, compared with those of PC-3N in the clonogenic survival assay. After 16 hr irradiation at 8 Gy, the percentage of apoptotic cells significantly increased in PC-3rP1 compared with PC-3N. Growth of PC-3rP1 was significantly lower than that of PC-3N after docetaxel treatment both in vitro and in vivo. These results indicate that restoration of IGFBP-rP1 to PC-3 cells increases both their radiosensitivity and chemosensitivity.
authors.affiliation: Department of Urology, Integrated Health Sciences, Institute of Biomedical & Health Sciences, Hiroshima University, Hiroshima, Japan. sekimitsuhiro0216@yahoo.co.jp
authors.forename: Mitsuhiro
authors.initials: M
authors.lastname: Seki
authors.forename: Jun
authors.initials: J
authors.lastname: Teishima
authors.forename: Hideki
authors.initials: H
authors.lastname: Mochizuki
authors.forename: Kazuaki
authors.initials: K
authors.lastname: Mutaguchi
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Yasumoto
authors.forename: Kiyotaka
authors.initials: K
authors.lastname: Oka
authors.forename: Hirotaka
authors.initials: H
authors.lastname: Nagamatsu
authors.forename: Koichi
authors.initials: K
authors.lastname: Shoji
authors.forename: Akio
authors.initials: A
authors.lastname: Matsubara
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000494:pharmacology*; D017209:Apoptosis / Q000187:drug effects / Q000528:radiation effects; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects; D002470:Cell Survival / Q000187:drug effects / Q000528:radiation effects; D000077143:Docetaxel; D004305:Dose-Response Relationship, Drug; D004307:Dose-Response Relationship, Radiation; D019008:Drug Resistance, Neoplasm; D059565:G2 Phase Cell Cycle Checkpoints / Q000187:drug effects / Q000528:radiation effects; D006801:Humans; D018969:Insulin-Like Growth Factor Binding Proteins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D008807:Mice, Inbred BALB C; D008819:Mice, Nude; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy*; D043823:Taxoids / Q000494:pharmacology*; D013997:Time Factors; D014162:Transfection; D047368:Tumor Burden / Q000187:drug effects / Q000528:radiation effects; D023041:Xenograft Model Antitumor Assays
chemical_list: D000970:Antineoplastic Agents; D018969:Insulin-Like Growth Factor Binding Proteins; D043823:Taxoids; C102529:insulin-like growth factor binding protein-related protein 1; D000077143:Docetaxel