title: Regulation of the hedgehog signaling by the mitogen-activated protein kinase cascade in gastric cancer.
abstract: The hedgehog and mitogen-activated protein kinase (MAPK) signaling pathways regulate growth in many tumors, suggesting cooperation between these two pathways in the regulation of cell proliferation. However, interactions between these pathways have not been extensively studied. We assessed cross-talk between hedgehog and MAPK signaling in the regulation of cell proliferation in gastric cancer. We showed that PTCH expression was significantly correlated with extracellular signal-regulated kinase (ERK) 1/2 phosphorylation (P = 0.016) as well as SHH expression (P = 0.034) in the 35 gastric cancers assessed by immunohistochemistry. Indeed, MAPK signaling increased the GLI transcriptional activity and induced the expression of hedgehog target genes in gastric cancer cells. The inductive effect of activated KRAS and mitogen-activated protein/extracellular signal-regulated kinase kinase (MEK) 1 was blocked by the suppressor of fused (SUFU), indicating that MAPK signaling regulates GLI activity via a SUFU-independent process. Moreover, the deletion of the NH2-terminal domain of GLI1 gene resulted in reduced response to MEK1 stimulation. Our results suggest that the KRAS-MEK-ERK cascade has a positive regulatory role in GLI transcriptional activity in gastric cancer.
authors.affiliation: Department of Gastroenterology, Graduate School of Medicine, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
authors.forename: Motoko
authors.initials: M
authors.lastname: Seto
authors.forename: Miki
authors.initials: M
authors.lastname: Ohta
authors.forename: Yoshinari
authors.initials: Y
authors.lastname: Asaoka
authors.forename: Tsuneo
authors.initials: T
authors.lastname: Ikenoue
authors.forename: Motohisa
authors.initials: M
authors.lastname: Tada
authors.forename: Koji
authors.initials: K
authors.lastname: Miyabayashi
authors.forename: Dai
authors.initials: D
authors.lastname: Mohri
authors.forename: Yasuo
authors.initials: Y
authors.lastname: Tanaka
authors.forename: Hideaki
authors.initials: H
authors.lastname: Ijichi
authors.forename: Keisuke
authors.initials: K
authors.lastname: Tateishi
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Kanai
authors.forename: Takao
authors.initials: T
authors.lastname: Kawabe
authors.forename: Masao
authors.initials: M
authors.lastname: Omata
mesh_terms: D002288:Adenocarcinoma, Mucinous / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D002291:Carcinoma, Papillary / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D066246:ErbB Receptors / Q000235:genetics; D005260:Female; D005784:Gene Amplification; D053823:Hedgehog Proteins / Q000378:metabolism; D006801:Humans; D007124:Immunoenzyme Techniques; D048031:JNK Mitogen-Activated Protein Kinases / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism; D020929:Mitogen-Activated Protein Kinase Kinases / Q000378:metabolism; D020928:Mitogen-Activated Protein Kinases / Q000378:metabolism*; D000072079:Patched Receptors; D000072081:Patched-1 Receptor; D010766:Phosphorylation; D016755:Proto-Oncogene Proteins c-jun / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000378:metabolism*; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013274:Stomach Neoplasms / Q000235:genetics / Q000378:metabolism* / Q000473:pathology; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism; D000071676:Zinc Finger Protein GLI1; D048051:p38 Mitogen-Activated Protein Kinases / Q000378:metabolism; D018631:ras Proteins / Q000378:metabolism
chemical_list: C400551:GLI1 protein, human; D053823:Hedgehog Proteins; C000606236:PTCH1 protein, human; D000072079:Patched Receptors; D000072081:Patched-1 Receptor; D016755:Proto-Oncogene Proteins c-jun; D012333:RNA, Messenger; D011956:Receptors, Cell Surface; D012097:Repressor Proteins; C509239:SHH protein, human; C490764:SUFU protein, human; D014157:Transcription Factors; D000071676:Zinc Finger Protein GLI1; C512478:EGFR protein, human; D066246:ErbB Receptors; D048031:JNK Mitogen-Activated Protein Kinases; D048052:Mitogen-Activated Protein Kinase 3; D020928:Mitogen-Activated Protein Kinases; D048051:p38 Mitogen-Activated Protein Kinases; D020929:Mitogen-Activated Protein Kinase Kinases; D018631:ras Proteins