title: Regulation of gene expression in prostate cancer cells with an artificially constructed promoter responsive to radiation.
abstract: A promoter library was developed that is composed of DNA fragments constructed by randomly elongating the cis-acting elements of transcription factors presumably activated in prostate cancer by radiation, and linking to the TATA-box sequence. One promoter with the strongest reactivity to X-ray in the LNCap cells of the library was chosen and improved by the introduction of random mutations. The resultant promoter was designated clone 880-8, showing the highest dose-dependent activity enhancement with X-ray irradiation (X-irradiation). A recombinant retrovirus expressing the luciferase gene under the control of clone 880-8 was infected into LNCap cells that showed 9.12±0.36-fold enhancement of luciferase activity 12 h after X-irradiation at 10 Gy. When the infected cells were inoculated onto nude mice, enhancement of luciferase expression was 4.27±1.36-fold 12 h after X-irradiation at 10 Gy. When LNCap was infected with another recombinant carrying the fcy::fur gene downstream from clone 880-8, fcy::fur expression was enhanced by X-irradiation. It was also shown to increase the dose-dependent cell killing ratio with 5-FC as compared with a counterpart without X-irradiation. These results suggest that the method used in this study is effective to construct a promoter responsive to stimulation. Such promoters can be used for stimulation-controlled gene therapies.
authors.affiliation: Department of Urology, Graduate School of Medicine and Pharmaceutical Sciences for Research, University of Toyama, Toyama, Japan.
authors.forename: A
authors.initials: A
authors.lastname: Morii
authors.forename: R
authors.initials: R
authors.lastname: Ogawa
authors.forename: A
authors.initials: A
authors.lastname: Watanabe
authors.forename: S
authors.initials: S
authors.lastname: Kakutani
authors.forename: Q L
authors.initials: QL
authors.lastname: Zhao
authors.forename: K
authors.initials: K
authors.lastname: Kume
authors.forename: T
authors.initials: T
authors.lastname: Kondo
authors.forename: H
authors.initials: H
authors.lastname: Fuse
mesh_terms: D000818:Animals; D045744:Cell Line, Tumor; D004307:Dose-Response Relationship, Radiation; D015972:Gene Expression Regulation, Neoplastic / Q000528:radiation effects; D015316:Genetic Therapy / Q000379:methods*; D006801:Humans; D008156:Luciferases / Q000235:genetics / Q000378:metabolism*; D008297:Male; D051379:Mice; D011401:Promoter Regions, Genetic; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism*; D016385:TATA Box / Q000235:genetics*; D014157:Transcription Factors / Q000235:genetics; D014183:Transplantation, Heterologous; D014965:X-Rays
chemical_list: D014157:Transcription Factors; D008156:Luciferases