title: REG I enhances chemo- and radiosensitivity in squamous cell esophageal cancer cells.
abstract: Identification of reliable markers of chemo- and radiosensitivity and the key molecules that enhance the susceptibility of squamous esophageal cancer cells to anticancer treatments would be highly desirable. To test whether regenerating gene (REG) I expression enhances chemo- and radiosensitivity in esophageal squamous cell carcinoma cells, we used MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide) assays to compare the chemo- and radiosensitivities of untransfected TE-5 and TE-9 cells with those of cells stably transfected with REG Ialpha and Ibeta. We then used flow cytometry to determine whether REG I expression alters cell cycle progression. No REG I mRNA or protein were detected in untransfected TE-5 and TE-9 cells. Transfection with REG Ialpha and Ibeta led to strong expression of both REG I mRNA and protein in TE-5 and TE-9 cells, which in turn led to significant increases in both chemo- and radiosensitivity. Cell cycle progression was unaffected by REG I expression. REG I thus appears to enhance the chemo- and radiosensitivity of squamous esophageal cancer cells, which suggests that it may be a useful target for improved and more individualized treatments for patients with esophageal squamous cell carcinoma.
authors.affiliation: Department of Biochemistry, Akita University School of Medicine, 1-1-1 Hondo, Akita 010-8543, Japan.
authors.forename: Kaori
authors.initials: K
authors.lastname: Hayashi
authors.forename: Satoru
authors.initials: S
authors.lastname: Motoyama
authors.forename: Souichi
authors.initials: S
authors.lastname: Koyota
authors.forename: Yukio
authors.initials: Y
authors.lastname: Koizumi
authors.forename: Jingshu
authors.initials: J
authors.lastname: Wang
authors.forename: Shin
authors.initials: S
authors.lastname: Takasawa
authors.forename: Asako
authors.initials: A
authors.lastname: Itaya-Hironaka
authors.forename: Sumiyo
authors.initials: S
authors.lastname: Sakuramoto-Tsuchida
authors.forename: Kiyotomi
authors.initials: K
authors.lastname: Maruyama
authors.forename: Hajime
authors.initials: H
authors.lastname: Saito
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Minamiya
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Ogawa
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Sugiyama
mesh_terms: D000964:Antimetabolites, Antineoplastic / Q000378:metabolism / Q000627:therapeutic use; D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects / Q000528:radiation effects; D004307:Dose-Response Relationship, Radiation; D004938:Esophageal Neoplasms / Q000188:drug therapy / Q000235:genetics / Q000378:metabolism* / Q000473:pathology / Q000532:radiotherapy; D005472:Fluorouracil / Q000378:metabolism* / Q000627:therapeutic use; D005562:Formazans / Q000378:metabolism; D006801:Humans; D051847:Lithostathine / Q000235:genetics / Q000378:metabolism*; D011506:Proteins / Q000378:metabolism; D012333:RNA, Messenger / Q000378:metabolism; D011836:Radiation Tolerance / Q000235:genetics*; D013778:Tetrazolium Salts / Q000378:metabolism; D014162:Transfection
chemical_list: D000964:Antimetabolites, Antineoplastic; D005562:Formazans; D051847:Lithostathine; D011506:Proteins; C497617:REG1A protein, human; D012333:RNA, Messenger; D013778:Tetrazolium Salts; C079782:MTT formazan; D005472:Fluorouracil