title: Identification of c-Src as a potential therapeutic target for gastric cancer and of MET activation as a cause of resistance to c-Src inhibition.
abstract: Therapeutic strategies that target c-Src hold promise for a wide variety of cancers. We have now investigated both the effects of dasatinib, which inhibits the activity of c-Src and several other kinases, on cell growth as well as the mechanism of dasatinib resistance in human gastric cancer cell lines. Immunoblot analysis revealed the activation of c-Src at various levels in most gastric cancer cell lines examined. Dasatinib inhibited the phosphorylation of extracellular signal-regulated kinase (ERK) and induced G(1) arrest, as revealed by flow cytometry, in a subset of responsive cell lines. In other responsive cell lines, dasatinib inhibited both ERK and AKT phosphorylation and induced apoptosis, as revealed by an increase in caspase-3 activity and cleavage of poly(ADP-ribose) polymerase. Depletion of c-Src by RNA interference also induced G(1) arrest or apoptosis in dasatinib-responsive cell lines, indicating that the antiproliferative effect of dasatinib is attributable to c-Src inhibition. Gastric cancer cell lines positive for the activation of MET were resistant to dasatinib. Dasatinib had no effect on ERK or AKT signaling, whereas the MET inhibitor PHA-665752 induced apoptosis in these cells. The subsets of gastric cancer cells defined by a response to c-Src or MET inhibitors were distinct and nonoverlapping. Our results suggest that c-Src is a promising target for the treatment of gastric cancer and that analysis of MET amplification might optimize patient selection for treatment with c-Src inhibitors.
authors.affiliation: Department of Medical Oncology, Kinki University School of Medicine, 377-2 Ohno-higashi, Osaka-Sayama, Osaka, Japan.
authors.forename: Wataru
authors.initials: W
authors.lastname: Okamoto
authors.forename: Isamu
authors.initials: I
authors.lastname: Okamoto
authors.forename: Takeshi
authors.initials: T
authors.lastname: Yoshida
authors.forename: Kunio
authors.initials: K
authors.lastname: Okamoto
authors.forename: Ken
authors.initials: K
authors.lastname: Takezawa
authors.forename: Erina
authors.initials: E
authors.lastname: Hatashita
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yamada
authors.forename: Kiyoko
authors.initials: K
authors.lastname: Kuwata
authors.forename: Tokuzo
authors.initials: T
authors.lastname: Arao
authors.forename: Kazuyoshi
authors.initials: K
authors.lastname: Yanagihara
authors.forename: Masahiro
authors.initials: M
authors.lastname: Fukuoka
authors.forename: Kazuto
authors.initials: K
authors.lastname: Nishio
authors.forename: Kazuhiko
authors.initials: K
authors.lastname: Nakagawa
mesh_terms: D000970:Antineoplastic Agents / Q000008:administration & dosage*; D017209:Apoptosis / Q000187:drug effects; D000081247:CSK Tyrosine-Protein Kinase; D002277:Carcinoma / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D000069439:Dasatinib; D016503:Drug Delivery Systems; D004353:Drug Evaluation, Preclinical; D019008:Drug Resistance, Neoplasm / Q000187:drug effects; D004789:Enzyme Activation / Q000502:physiology; D006801:Humans; D007211:Indoles / Q000494:pharmacology; D020128:Inhibitory Concentration 50; D047428:Protein Kinase Inhibitors / Q000008:administration & dosage; D011505:Protein-Tyrosine Kinases / Q000037:antagonists & inhibitors*; D011518:Proto-Oncogene Proteins / Q000037:antagonists & inhibitors*; D019859:Proto-Oncogene Proteins c-met / Q000037:antagonists & inhibitors / Q000378:metabolism*; D011743:Pyrimidines / Q000008:administration & dosage / Q000494:pharmacology; D017978:Receptors, Growth Factor / Q000037:antagonists & inhibitors / Q000378:metabolism*; D013274:Stomach Neoplasms / Q000188:drug therapy* / Q000378:metabolism / Q000473:pathology; D013450:Sulfones / Q000494:pharmacology; D013844:Thiazoles / Q000008:administration & dosage / Q000494:pharmacology; D019061:src-Family Kinases
chemical_list: C480541:5-((2,6-dichlorobenzyl)sulfonyl)-3-((3,5-dimethyl-4-((2-(pyrrolidin-1-ylmethyl)pyrrolidin-1-yl)carbonyl)-1H-pyrrol-2-yl)methylene)-1,3-dihydro-2H-indol-2-one; D000970:Antineoplastic Agents; D007211:Indoles; D047428:Protein Kinase Inhibitors; D011518:Proto-Oncogene Proteins; D011743:Pyrimidines; D017978:Receptors, Growth Factor; D013450:Sulfones; D013844:Thiazoles; C491743:MET protein, human; D011505:Protein-Tyrosine Kinases; D019859:Proto-Oncogene Proteins c-met; D000081247:CSK Tyrosine-Protein Kinase; D019061:src-Family Kinases; C000631346:CSK protein, human; D000069439:Dasatinib