title: Small interference RNA-mediated silencing of prostate stem cell antigen attenuates growth, reduces migration and invasion of human prostate cancer PC-3M cells.
abstract: OBJECTIVE
  Prostate stem cell antigen (PSCA), a glycosylphosphatidylinositol (GPI)-anchored cell surface glycoprotein, is highly expressed in both local and metastatic prostate cancer (CaP). Elevated PSCA expression has been shown to correlate with malignant phenotype and clinical progression. The purpose of the current study is to investigate the therapeutic potential of small interference RNA (siRNA) targeting PSCA on human CaP cells.
  
  
  METHODS
  A set of two siRNAs directed different regions of human PSCA (siRNA-PSCA) were designed and transfected into a human CaP PC-3M cell line. The silencing effect was screened by RT-PCR and Western blotting. The biological effects of siRNA-PSCA on PC-3M cells were investigated by examining the cell proliferation through 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell cycle distribution through flow cytometry, and migration and invasion potencies through transwell invasion assay upon the PSCA silencing.
  
  
  RESULTS
  PC-3M cells had positive PSCA expression on immunocytochemical assay. PSCA expression was depleted at 48 hours after transfection with siRNA-PSCA. Silencing of PSCA significantly suppressed cell proliferation. Cell cycle assay showed that the anti-proliferation effect of siRNA-PSCA was mediated by arresting cells in the G0/G1 phase rather than apoptosis. Furthermore, PSCA knockdown resulted in a marked decrease of cell migration and invasion capabilities in PC-3M cells.
  
  
  CONCLUSIONS
  The present study provides the first evidence that silencing PSCA using siRNA can inhibit the proliferation and invasiveness properties of human CaP cells, which may provide a promising therapeutic strategy for CaP and open a novel avenue toward the investigation of the role of PSCA overexpression in cancers.
authors.affiliation: Department of Urology, Minimally Invasive Surgery Center, The First Affiliated Hospital of Guangzhou Medical College, Guangdong Key Laboratory of Urology, Guangzhou, China. zgzhaodr@yahoo.com.cn
authors.forename: Zhigang
authors.initials: Z
authors.lastname: Zhao
authors.forename: Wenjing
authors.initials: W
authors.lastname: Ma
authors.forename: Guohua
authors.initials: G
authors.lastname: Zeng
authors.forename: Defeng
authors.initials: D
authors.lastname: Qi
authors.forename: Lili
authors.initials: L
authors.lastname: Ou
authors.forename: Yeping
authors.initials: Y
authors.lastname: Liang
mesh_terms: D000951:Antigens, Neoplasm / Q000235:genetics* / Q000378:metabolism; D015153:Blotting, Western; D002453:Cell Cycle / Q000235:genetics; D045744:Cell Line, Tumor; D002465:Cell Movement / Q000235:genetics*; D049109:Cell Proliferation; D002470:Cell Survival / Q000235:genetics; D005434:Flow Cytometry; D058851:GPI-Linked Proteins / Q000235:genetics / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000235:genetics* / Q000378:metabolism; D011471:Prostatic Neoplasms / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors
chemical_list: D000951:Antigens, Neoplasm; D058851:GPI-Linked Proteins; D009363:Neoplasm Proteins; C110843:PSCA protein, human