title: Expression of ErbB receptors and their cognate ligands in gastric and colon cancer cell lines.
abstract: BACKGROUND
  ErbB receptors and their cognate ligands are implicated in cancer progression. Their expression in gastrointestinal cancer, however, has not been systemically studied.
  
  
  METHODS
  The expression of four ErbB receptors and a panel of ErbB ligands were determined by reverse transcription-PCR in two gastric (TMK1, MKN-45) and two colon (SW1116, HT-29) cancer cell lines. Cell proliferation was measured by MTT assay while gene knockdown was achieved by RNA interference.
  
  
  RESULTS
  ErbB1, ErbB2 and ErbB3 receptors and five known or putative ErbB ligands, namely, epiregulin, epidermal growth factor (EGF), heparin-binding EGF, transforming growth factor alpha (TGFalpha) and neuroglycan-C were expressed in all four cell lines. Knockdown of neuroglycan-C, however, did not affect cell proliferation.
  
  
  CONCLUSIONS
  This study profiles the expression of ErbB receptors and their cognate ligands in gastric and colon cancer cells. These findings might lay the basis for the development of ErbB pathway-directed therapeutics for gastrointestinal cancer.
authors.affiliation: Department of Medicine and Therapeutics, The Chinese University of Hong Kong, Shatin, N.T., Hong Kong, People's Republic of China.
authors.forename: William Ka Kei
authors.initials: WK
authors.lastname: Wu
authors.forename: Timothy Tim Ming
authors.initials: TT
authors.lastname: Tse
authors.forename: Joseph Jao Yiu
authors.initials: JJ
authors.lastname: Sung
authors.forename: Zhi Jie
authors.initials: ZJ
authors.lastname: Li
authors.forename: Le
authors.initials: L
authors.lastname: Yu
authors.forename: Chi Hin
authors.initials: CH
authors.lastname: Cho