AIM： To examine whether lysophosphatidic acid （LPA） induces phosphorylation of c-Met and epidermal growth factor receptor （EGFR）, both of which have been proposed as prognostic markers of colorectal cancer, and w...AIM： To examine whether lysophosphatidic acid （LPA） induces phosphorylation of c-Met and epidermal growth factor receptor （EGFR）, both of which have been proposed as prognostic markers of colorectal cancer, and whether LPA induces cyclooxygenase-2 （COX-2） expression in human colon cancer cells. METHODS： Using a human colon cancer cell line, LoVo cells, we performed immunoprecipitation analysis, followed by Western blot analysis. We also examined whether LPA induced COX-2 expression, by Western blot analysis. RESULTS： Immunoprecipitation analysis revealed that 10 μmol/L LPA induced tyrosine phosphorylation of c-Met and EGFR in LoVo cells within a few minutes. We found that c-Met tyrosine phosphorylation induced by LPA was not attenuated by pertussis toxin or a matrix metalloproteinase inhibitor, in marked contrast to the results for EGFR. In addition, 0.2-40 IJmol/L LPA induced COX-2 expression in a dose-dependent manner. CONCLUSION： Our results suggest that LPA acts upstream of various receptor tyrosine kinases （RTKs） and COX-2, and thus may act as a potent stimulator of colorectal cancer. 2005 The WJG Press and Elsevier Inc. All rights reserved.展开更多
目的探讨c-Met受体酪氨酸激酶抑制剂卡博替尼作为抗产单核细胞李斯特菌(Lis te ria monocytoge ne s,LM)感染新型药物的可能性。方法 6周龄C57BL/6小鼠随机分为卡博替尼组、氨苄青霉素(Amp)组、卡博替尼和氨苄青霉素联合用药组和PBS对...目的探讨c-Met受体酪氨酸激酶抑制剂卡博替尼作为抗产单核细胞李斯特菌(Lis te ria monocytoge ne s,LM)感染新型药物的可能性。方法 6周龄C57BL/6小鼠随机分为卡博替尼组、氨苄青霉素(Amp)组、卡博替尼和氨苄青霉素联合用药组和PBS对照组。腹腔注射LM菌液后,再分别灌胃给予卡博替尼20μg/g、腹腔注射氨苄青霉素20μg/g、卡博替尼和氨苄青霉素联合用药、以及腹腔注射等量PBS,比较4组小鼠的生存曲线、血液和脑组织细菌载量、血清IL-10和脑脊液中NF-κB p65含量、脑组织中依文思蓝(EB)含量以及脑组织病理变化。结果卡博替尼组比对照组小鼠生存率增高、血液和脑组织的细菌载量明显减少(P<0.05,P<0.001);血清IL-10和NF-κB p65含量显著降低(P<0.05,P<0.01);脑组织EB量降低(P<0.001),脑组织病理变化减轻。联合用药组比卡博替尼单独用药组小鼠血液和脑细菌载量(P均<0.001)、血清IL-10和NF-κB p65含量(P<0.01,P<0.001)、脑组织EB量均明显减少(P<0.001)。结论酪氨酸激酶抑制剂卡博替尼对LM感染具有阻断作用,为研发新型抗胞内感染药物提供重要理论依据。展开更多
基金Supported by a Grant-in-Aid for Scientific Research from the Ministry of Education, Culture, Sports, Science and Technology of Japan and a grant from the Ministry of Health, Labour and Welfare of Japan
文摘AIM： To examine whether lysophosphatidic acid （LPA） induces phosphorylation of c-Met and epidermal growth factor receptor （EGFR）, both of which have been proposed as prognostic markers of colorectal cancer, and whether LPA induces cyclooxygenase-2 （COX-2） expression in human colon cancer cells. METHODS： Using a human colon cancer cell line, LoVo cells, we performed immunoprecipitation analysis, followed by Western blot analysis. We also examined whether LPA induced COX-2 expression, by Western blot analysis. RESULTS： Immunoprecipitation analysis revealed that 10 μmol/L LPA induced tyrosine phosphorylation of c-Met and EGFR in LoVo cells within a few minutes. We found that c-Met tyrosine phosphorylation induced by LPA was not attenuated by pertussis toxin or a matrix metalloproteinase inhibitor, in marked contrast to the results for EGFR. In addition, 0.2-40 IJmol/L LPA induced COX-2 expression in a dose-dependent manner. CONCLUSION： Our results suggest that LPA acts upstream of various receptor tyrosine kinases （RTKs） and COX-2, and thus may act as a potent stimulator of colorectal cancer. 2005 The WJG Press and Elsevier Inc. All rights reserved.
文摘目的探讨c-Met受体酪氨酸激酶抑制剂卡博替尼作为抗产单核细胞李斯特菌(Lis te ria monocytoge ne s,LM)感染新型药物的可能性。方法 6周龄C57BL/6小鼠随机分为卡博替尼组、氨苄青霉素(Amp)组、卡博替尼和氨苄青霉素联合用药组和PBS对照组。腹腔注射LM菌液后,再分别灌胃给予卡博替尼20μg/g、腹腔注射氨苄青霉素20μg/g、卡博替尼和氨苄青霉素联合用药、以及腹腔注射等量PBS,比较4组小鼠的生存曲线、血液和脑组织细菌载量、血清IL-10和脑脊液中NF-κB p65含量、脑组织中依文思蓝(EB)含量以及脑组织病理变化。结果卡博替尼组比对照组小鼠生存率增高、血液和脑组织的细菌载量明显减少(P<0.05,P<0.001);血清IL-10和NF-κB p65含量显著降低(P<0.05,P<0.01);脑组织EB量降低(P<0.001),脑组织病理变化减轻。联合用药组比卡博替尼单独用药组小鼠血液和脑细菌载量(P均<0.001)、血清IL-10和NF-κB p65含量(P<0.01,P<0.001)、脑组织EB量均明显减少(P<0.001)。结论酪氨酸激酶抑制剂卡博替尼对LM感染具有阻断作用,为研发新型抗胞内感染药物提供重要理论依据。
