Hepatocyte growth factor-mediated gastrin-releasing peptide induces IL-8 expression through Ets-1 in gastric cancer cells.
Gastric cancer cells secrete a variety of proangiogenic molecules, including IL-8 and VEGF. However, factors regulating the expression of proangiogenic genes for gastric cancer remain largely undefined. We investigated the role of HGF-induced activation of GRP and Ets-1 transcription factor in expression of the proangiogenic factor IL-8. The genes associated with angiogenesis induced by HGF were screened using cDNA micro-array technology in two gastric cancer cell lines (NUGC-3 and MKN-28). First, GRP RNA and protein were confirmed to be upregulated. Then, expression of GRP, Ets-1, and IL-8 were further estimated by Western blot analysis. A role for Ets-1 in HGF-induced upregulation of IL-8 was determined by knockdown of Ets-1 with Ets-1 sh-RNA and a chromatin immune precipitation assay. The levels of GRP, Ets-1, and IL-8 were upregulated in cells treated with HGF in a dose-dependent manner. HGF-induced expression of Ets-1 and IL-8 was increased more by GRP treatment and inhibited by pretreatment with an ERK 1/2 inhibitor (PD098059). HGF-induced upregulation of IL-8 was repressed by Ets-1 knockdown. HGF enhanced the binding activity of Ets-1 to the IL-8 promoter in control cells, but not in the Ets-1 shRNA cells. We confirmed the functional role of HGF-induced Ets-1 in activation of the IL-8 promoter by the reporter gene assay. Downregulation of IL-8 also decreased in vitro cell invasion. In conclusion, HGF mediated the GRP induction of IL-8 expression through Ets-1, which thus might serve as a promising target for gastric cancer therapy.
Department of Hematology-Oncology, College of Medicine, Yeungnam University, Daegu, Korea.
Kyung Hee
KH
Lee
Sung Ae
SA
Koh
Jae-Ryong
JR
Kim
D000230:Adenocarcinoma / Q000098:blood supply / Q000235:genetics* / Q000473:pathology; D001483:Base Sequence; D045744:Cell Line, Tumor / Q000473:pathology; D048049:Extracellular Signal-Regulated MAP Kinases / Q000037:antagonists & inhibitors / Q000502:physiology; D005419:Flavonoids / Q000494:pharmacology; D019886:Gastrin-Releasing Peptide / Q000502:physiology*; D015972:Gene Expression Regulation, Neoplastic / Q000187:drug effects; D055785:Gene Knockdown Techniques; D017930:Genes, Reporter; D016762:Genes, fos; D016758:Genes, jun; D017228:Hepatocyte Growth Factor / Q000502:physiology*; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis* / Q000235:genetics; D020935:MAP Kinase Signaling System / Q000187:drug effects; D008969:Molecular Sequence Data; D009361:Neoplasm Invasiveness; D009363:Neoplasm Proteins / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D009389:Neovascularization, Pathologic / Q000235:genetics*; D011401:Promoter Regions, Genetic; D050784:Proto-Oncogene Protein c-ets-1 / Q000235:genetics / Q000502:physiology*; D034741:RNA, Small Interfering / Q000494:pharmacology; D013274:Stomach Neoplasms / Q000098:blood supply / Q000235:genetics* / Q000473:pathology
C494041:ETS1 protein, human; D005419:Flavonoids; C066855:HGF protein, human; D016209:Interleukin-8; D009363:Neoplasm Proteins; D050784:Proto-Oncogene Protein c-ets-1; D034741:RNA, Small Interfering; D017228:Hepatocyte Growth Factor; D019886:Gastrin-Releasing Peptide; D048049:Extracellular Signal-Regulated MAP Kinases; C093973:2-(2-amino-3-methoxyphenyl)-4H-1-benzopyran-4-one