Role of heparin-binding EGF-related peptides in proliferation and apoptosis of activated ras-stimulated intestinal epithelial cells.
The ras mutation is a common and critical step in carcinogenesis. Autocrine growth factors are also known to play an important role in cancer cell growth and transformation. However, the contribution of autocrine growth factors in regulation of proliferation and apoptosis of activated ras-stimulated intestinal epithelium is not fully understood. Therefore, we constructed activated ras-transfected intestinal epithelial cell clones (IEC-ras) to examine the role of epidermal growth factor (EGF)-related peptides in the behavior of IEC-ras. Overexpression of EGF family growth factors (transforming growth factor alpha, heparin-binding EGF-like growth factor, amphiregulin and betacellulin) and stronger phosphorylation of the EGF receptor was observed in IEC-ras compared with control cells. IEC-ras proliferated more rapidly than control cells, and a specific EGF receptor kinase inhibitor, AG 1478, abolished the increased proliferation of IEC-ras. Heparitinase and chlorate also prevented increased proliferation of IEC-ras. Additionally, IEC-ras expressed more bcl-2 and was more resistant to apoptosis induction by UV radiation and mitomycin C. AG 1478 suppressed bcl-2 expression and inhibited resistance to apoptosis of IEC-ras. Heparitinase and chlorate had effects similar to those of AG 1478. Our data indicate that heparin-binding EGF family growth factors play an important role in both increased proliferation and resistance to apoptosis of ras-stimulated intestinal epithelial cells.
Zushi
S
S
Second Department of Internal Medicine, Osaka University Medical School, Suita, Japan.
Shinomura
Y
Y
Kiyohara
T
T
Miyazaki
Y
Y
Tsutsui
S
S
Sugimachi
M
M
Higashimoto
Y
Y
Kanayama
S
S
Matsuzawa
Y
Y
D066258:Amphiregulin; D000818:Animals; D017209:Apoptosis / Q000235:genetics; D019898:Autocrine Communication; D066259:Betacellulin; D002455:Cell Division / Q000235:genetics; D002478:Cells, Cultured; D002704:Chlorates / Q000494:pharmacology; D017077:Culture Media, Conditioned; D066255:EGF Family of Proteins; D004815:Epidermal Growth Factor / Q000378:metabolism; D066246:ErbB Receptors / Q000378:metabolism; D011905:Genes, ras / Q000235:genetics; D006023:Glycoproteins / Q000378:metabolism; D006133:Growth Substances / Q000378:metabolism; D066257:Heparin-binding EGF-like Growth Factor; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins; D007413:Intestinal Mucosa / Q000166:cytology* / Q000378:metabolism*; D009570:Nitriles / Q000494:pharmacology; D010766:Phosphorylation; D011133:Polysaccharide-Lyases / Q000494:pharmacology; D017027:Protein Tyrosine Phosphatases / Q000037:antagonists & inhibitors; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D011799:Quinazolines / Q000494:pharmacology; D012313:RNA / Q000032:analysis; D051381:Rats; D014162:Transfection; D016211:Transforming Growth Factor alpha / Q000378:metabolism; D014407:Tumor Cells, Cultured; D020032:Tyrphostins; D015854:Up-Regulation; D018631:ras Proteins / Q000378:metabolism
C587848:AREG protein, human; D066258:Amphiregulin; C587850:Areg protein, rat; C587851:BTC protein, human; D066259:Betacellulin; C587853:Btc protein, rat; D002704:Chlorates; D017077:Culture Media, Conditioned; D066255:EGF Family of Proteins; D006023:Glycoproteins; D006133:Growth Substances; C587883:HBEGF protein, human; C587885:Hbegf protein, rat; D066257:Heparin-binding EGF-like Growth Factor; D036341:Intercellular Signaling Peptides and Proteins; D009570:Nitriles; D019253:Proto-Oncogene Proteins c-bcl-2; D011799:Quinazolines; D016211:Transforming Growth Factor alpha; D020032:Tyrphostins; C101044:RTKI cpd; D004815:Epidermal Growth Factor; D012313:RNA; D066246:ErbB Receptors; D017027:Protein Tyrosine Phosphatases; D018631:ras Proteins; D011133:Polysaccharide-Lyases; C021349:heparitinsulfate lyase