title: Six-transmembrane epithelial antigen of the prostate-1 plays a role for in vivo tumor growth via intercellular communication.
abstract: Six-transmembrane epithelial antigen of the prostate-1 (STEAP-1) is a novel cell surface protein overexpressed only in the prostate among normal tissues and various types of cancer including prostate, bladder, lung, and ovarian cancer. Although its function in prostate and tumor cells has been remained unclear, due to its unique and restricted expression, STEAP-1 is expected to be an attractive target for cancer therapy. Here, we show that knockdown of STEAP-1 in human cancer cells caused the retardation of tumor growth compared with wild type in vivo. In contrast, STEAP-1 introduced tumor cells augmented the tumor growth compared with STEAP-1-negative wild type cells. Using dye transfer assay, we demonstrate that the STEAP-1 is involved in intercellular communication between tumor cells and adjacent tumor stromal cells and therefore may play a key role for the tumor growth in vivo. These data indicate the inhibition of the STEAP-1 function or expression can be a new strategy for cancer therapy.
authors.affiliation: Department of Pathology, Sapporo Medical University School of Medicine, South 1, West 17, Chuo-ku, Sapporo 060-8556, Japan; Department of Oral Surgery, Sapporo Medical University School of Medicine, Sapporo, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Yamamoto
authors.forename: Yasuaki
authors.initials: Y
authors.lastname: Tamura
authors.forename: Jun-Ichi
authors.initials: J
authors.lastname: Kobayashi
authors.forename: Kenjirou
authors.initials: K
authors.lastname: Kamiguchi
authors.forename: Yoshihiko
authors.initials: Y
authors.lastname: Hirohashi
authors.forename: Akihiro
authors.initials: A
authors.lastname: Miyazaki
authors.forename: Toshihiko
authors.initials: T
authors.lastname: Torigoe
authors.forename: Hiroko
authors.initials: H
authors.lastname: Asanuma
authors.forename: Hiroyoshi
authors.initials: H
authors.lastname: Hiratsuka
authors.forename: Noriyuki
authors.initials: N
authors.lastname: Sato
mesh_terms: D000818:Animals; D000951:Antigens, Neoplasm / Q000235:genetics / Q000378:metabolism*; D002277:Carcinoma / Q000378:metabolism / Q000473:pathology*; D002450:Cell Communication; D045744:Cell Line, Tumor; D049109:Cell Proliferation; D006801:Humans; D008297:Male; D051379:Mice; D016688:Mice, Inbred NOD; D016513:Mice, SCID; D010088:Oxidoreductases / Q000235:genetics / Q000378:metabolism*; D011471:Prostatic Neoplasms / Q000378:metabolism / Q000473:pathology*; D017154:Stromal Cells / Q000378:metabolism / Q000502:physiology; D023041:Xenograft Model Antitumor Assays
chemical_list: D000951:Antigens, Neoplasm; C486624:Steap protein, mouse; D010088:Oxidoreductases; C432763:STEAP1 protein, human
keywords: Intercellular communication; STEAP-1; Tumor stromal cell; miRNA