title: The role of HGF/MET and FGF/FGFR in fibroblast-derived growth stimulation and lapatinib-resistance of esophageal squamous cell carcinoma.
abstract: BACKGROUND
  Although advanced esophageal squamous-cell carcinoma (ESCC) is treated using a multidisciplinary approach, outcomes remain unsatisfactory. The microenvironment of cancer cells has recently been shown to strongly influence the biologic properties of malignancies. We explored the effect of supernatant from esophageal fibroblasts on the cell growth and chemo-resistance of ESCC cell lines.
  
  
  METHODS
  We used 22 ESCC cell lines, isolated primary human esophageal fibroblasts and immortalized fibroblasts. We first examined cell proliferation induced by fibroblast supernatant. The effect of supernatant was evaluated to determine whether paracrine signaling induced by fibroblasts can influence the proliferation of cancer cells. Next, we examined the effects of adding growth factors HGF, FGF1, FGF7, and FGF10, to the culture medium of cancer cells. These growth factors are assumed to be present in the culture supernatants of fibroblasts and may exert a paracrine effect on the proliferation of cancer cells. We also examined the intrinsic role of HGF/MET and FGFs/FGFR in ESCC proliferation. In addition, we examined the inhibitory effect of lapatinib on ESCC cell lines and studied whether the fibroblast supernatants affect the inhibitory effect of lapatinib on ESCC cell proliferation. Finally, we tested whether the FGFR inhibitor PD-173074 could eliminate the rescue effect against lapatinib that was induced by fibroblast supernatants.
  
  
  RESULTS
  The addition of fibroblast supernatant induces cell proliferation in the majority of cell lines tested. The results of experiments to evaluate the effects of adding growth factors and kinase inhibitors suggests that the stimulating effect of fibroblasts was attributable in part to HGF/MET or FGF/FGFR. The results also indicate diversity in the degree of dependence on HGF/MET and FGF/FGFR among the cell lines. Though lapanitib at 1 μM inhibits cell proliferation by more than 50% in the majority of the ESCC cell lines, fibroblast supernatant can rescue the growth inhibition of ESCC cells. However, the rescue effect is abrogated by co-treatment with FGFR inhibitor.
  
  
  CONCLUSIONS
  These results demonstrate that cell growth of ESCC depends on diverse receptor tyrosine kinase signaling, in both cell-autonomous and cell-non-autonomous manners. The combined inhibition of these signals may hold promise for the treatment of ESCC.
authors.affiliation: Department of Surgery, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. shin.s@jichi.ac.jp.
authors.forename: Shin
authors.initials: S
authors.lastname: Saito
authors.affiliation: Department of Surgery, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. morishim@jichi.ac.jp.
authors.forename: Kazue
authors.initials: K
authors.lastname: Morishima
authors.affiliation: Department of Surgery, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. ui@jichi.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Ui
authors.affiliation: Department of Integrative Pathology, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. hihoshino@ab.auone-net.jp.
authors.forename: Hiroko
authors.initials: H
authors.lastname: Hoshino
authors.affiliation: Department of Integrative Pathology, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. matsubarad@mbn.nifty.com.
authors.forename: Daisuke
authors.initials: D
authors.lastname: Matsubara
authors.affiliation: Department of Genomic Pathology, Medical Research Institute, Tokyo Medical and Dental University, 1-5-45 Yushima, Bunkyo, Tokyo, 113-0034, Japan. isikawas-tky@umin.org.
authors.forename: Shumpei
authors.initials: S
authors.lastname: Ishikawa
authors.affiliation: Division of Genome Science, Research Center for Advanced Science and Technology, University of Tokyo, 4-6-1 Komaba, Meguro, Tokyo, 153-8904, Japan. haburata-tky@umin.ac.jp.
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Aburatani
authors.affiliation: Department of Pathology, Graduate School of Medicine, University of Tokyo, 7-3-1 Hongo, Bunkyo, Tokyo, 113-0033, Japan. mfukayama-tky@umin.net.
authors.forename: Masashi
authors.initials: M
authors.lastname: Fukayama
authors.affiliation: Department of Surgery, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. hosoyo@jichi.ac.jp.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Hosoya
authors.affiliation: Department of Surgery, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. sata@jichi.ac.jp.
authors.forename: Naohiro
authors.initials: N
authors.lastname: Sata
authors.affiliation: Department of Surgery, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. alefor@jichi.ac.jp.
authors.forename: Alan K
authors.initials: AK
authors.lastname: Lefor
authors.affiliation: Department of Surgery, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. yyasuda@jichi.ac.jp.
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Yasuda
authors.affiliation: Department of Integrative Pathology, Jichi Medical University, 3311-1 Yakushiji, Shimotsuke-City, Tochigi, 329-0498, Japan. tniki@jichi.ac.jp.
authors.forename: Toshiro
authors.initials: T
authors.lastname: Niki
mesh_terms: D002294:Carcinoma, Squamous Cell / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D018929:Cell Culture Techniques; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D017077:Culture Media, Conditioned / Q000494:pharmacology; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D004938:Esophageal Neoplasms / Q000188:drug therapy / Q000378:metabolism* / Q000473:pathology; D000077277:Esophageal Squamous Cell Carcinoma; D004947:Esophagus / Q000166:cytology; D005346:Fibroblast Growth Factors / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D005347:Fibroblasts / Q000166:cytology / Q000378:metabolism*; D017228:Hepatocyte Growth Factor / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D000077341:Lapatinib; D008969:Molecular Sequence Data; D019899:Paracrine Communication / Q000187:drug effects; D019859:Proto-Oncogene Proteins c-met / Q000378:metabolism; D011743:Pyrimidines / Q000494:pharmacology; D011799:Quinazolines / Q000494:pharmacology*; D017468:Receptors, Fibroblast Growth Factor / Q000037:antagonists & inhibitors / Q000378:metabolism
chemical_list: D017077:Culture Media, Conditioned; C066855:HGF protein, human; C115711:PD 173074; D011743:Pyrimidines; D011799:Quinazolines; D017468:Receptors, Fibroblast Growth Factor; D000077341:Lapatinib; D005346:Fibroblast Growth Factors; D017228:Hepatocyte Growth Factor; C491743:MET protein, human; D019859:Proto-Oncogene Proteins c-met