This review summarizes the current state of knowledge regarding the role of endothelial dysfunction in the pathogenesis of early and delayed intestinal radiation toxicity and discusses various endothelial-oriented int...This review summarizes the current state of knowledge regarding the role of endothelial dysfunction in the pathogenesis of early and delayed intestinal radiation toxicity and discusses various endothelial-oriented interventions aimed at reducing the risk of radiation enteropathy. Studies published in the biomedical literature during the past four decades and cited in PubMed, as well as clinical and laboratory data from our own research program are reviewed. The risk of injury to normal tissues limits the cancer cure rates that can be achieved with radiation therapy. During treatment of abdominal and pelvic tumors, the intestine is frequently a major close-limiting factor. Microvascular injury is a prominent feature of both early (inflammatory), as well as delayed (fibroproliferative) radiation injuries in the intestine and in many other normal tissues. Evidence from our and other laboratories suggests that endothelial dysfunction, notably a deficiency of endothelial thrombomodulin, plays a key role in the pathogenesis of these radiation responses. Deficient levels of thrombomodulin cause loss of vascular thromboresistance, excessive activation of cellular thrombin receptors by thrombin, and insufficient activation of protein C, a plasma protein with anticoagulant, anti-inflammatory, and cytoprotective properties. These changes are presumed to be critically involved in many aspects of early intestinal radiation toxicity and may sustain the fibroproliferative processes that lead to delayed intestinal dysfunction, fibrosis, and clinical complications. In conclusion, injury of vascular endothelium is important in the pathogenesis of the intestinal radiation response. Endothelial-oriented interventions are appealing strategies to prevent or treat normal tissue toxicity associated with radiation treatment of cancer.展开更多
Here,we used reverse transcription-PCR(RT-PCR) and western blot to detect protease-activated receptor(PAR) 1,PAR 2 and PAR 4 expression in cancer tissues and cell lines of esophageal squamous cell carcinoma,and invest...Here,we used reverse transcription-PCR(RT-PCR) and western blot to detect protease-activated receptor(PAR) 1,PAR 2 and PAR 4 expression in cancer tissues and cell lines of esophageal squamous cell carcinoma,and investigated the co-relationship between PAR expression and clinic-pathological data for esophageal cancer.The methylation of PAR4 gene promoter involved in esophageal carcinoma was also analyzed.By comparing the mRNA expressions of normal esophageal tissue and human esophageal epithelial cells(HEEpiC),we found that among the 28 cases of esophageal squamous cell carcinoma,PAR1(60%) and PAR2(71%) were elevated in 17 and 20 cases,respectively,and PAR4(68%) expression was lowered in 19 cases.Whereas,in human esophageal squamous cells(TE-1 and TE-10),PAR1 and PAR2 expression was increased but PAR4 was decreased.Combined with clinical data,the expression of PAR1 in poorly differentiated(P=0.016) and middle and lower parts of the esophagus(P=0.016) was higher; expression of PAR4 in poorly differentiated carcinoma was lower(P=0.049).Regarding TE-1 and TE-10 protein expression,we found that in randomized esophageal carcinoma,PAR1(P=0.027) and PAR2(P=0.039) expressions were increased,but lowered for PAR4(P=0.0001).In HEEpiC,TE-1,TE-10,esophageal and normal esophagus tissue samples(case No.7),the frequency of methylation at the 19 CpG loci of PAR4 was 35.4%,95.2%,83.8%,62.6% and 48.2%,respectively.Our results indicate that the expression of PAR1 and PAR2 in esophageal squamous cell carcinoma is increased but PAR4 is decreased.Hypermethylation of the promoter of the PAR4 gene may contribute to reduced expression of PAR4 in esophageal squamous cell carcinoma.展开更多
AIM: To investigate the mechanism of interleukin (IL)-6 secretion through blocking the IL-17A/IL-17A recepto (IL-17RA) signaling pathway with a short hairpin RNA (shRNA) in hepatic stellate cells (HSCs) in vitro . MET...AIM: To investigate the mechanism of interleukin (IL)-6 secretion through blocking the IL-17A/IL-17A recepto (IL-17RA) signaling pathway with a short hairpin RNA (shRNA) in hepatic stellate cells (HSCs) in vitro . METHODS: HSCs were derived from the livers of adul male Sprague-Dawley rats. IL-6 expression was evalu ated using real-time quantitative polymerase chain reaction and enzyme linked immunosorbent assay. The phosphorylation activity of p38 mitogen activated pro tein kinases (MAPK) and extracellular regulated pro tein kinases (ERK) 1/2 upon induction by IL-17A and suppression by IL-17RA shRNA were examined using Western blotting.RESULTS: IL-6 expression induced by IL-17A was significantly increased compared to control in HSCs (P < 0.01 in a dose-dependent manner). Suppression of IL17RA using lentiviral-mediated shRNA inhibited IL-6 expression induced by IL-17A compared to group with only IL-17A treatment (1.44 ± 0.17 vs 4.07 ± 0.43, P < 0.01). IL-17A induced rapid phosphorylation of p38 MAPK and ERK1/2 after 5 min exposure, and showed the strongest levels of phosphorylation of p38 MAPK and ERK1/2 at 15 min in IL-17A-treated HSCs. IL-6 mRNA expression induced by IL-17A (100 ng/mL) for 3 h exposure was inhibited by preincubation with specific inhibitors of p38 MAPK (SB-203580) and ERK1/2 (PD-98059) compared to groups without inhibitors preincubation (1.67 ± 0.24, 2.01 ± 0.10 vs 4.08 ± 0.59, P < 0.01). Moreover, lentiviral-mediated IL-17RA shRNA 1 inhibited IL-17A-induced IL-6 mRNA expression compared to random shRNA in HSCs (1.44 ± 0.17 vs 3.98 ± 0.68, P < 0.01). Lentiviral-mediated IL17RA shRNA 1 inhibited phosphorylation of p38 MAPK and ERK1/2 induced by 15 min IL-17A (100 ng/mL) exposure. CONCLUSION: Down-regulation of the IL-17RA receptor by shRNA decreased IL-6 expression induced by IL-17A via p38 MAPK and ERK1/2 phosphorylation in HSCs. Suppression of IL-17RA expression may be a strategy to reduce the inflammatory response induced by IL-17A in the liver.展开更多
AIM:To gain insights into the molecular action of erlotinib in pancreatic cancer (PC) cells. METHODS:Two PC cell lines, BxPC-3 and Capan-1, were treated with various concentrations of erlotinib, the specific mitogen-a...AIM:To gain insights into the molecular action of erlotinib in pancreatic cancer (PC) cells. METHODS:Two PC cell lines, BxPC-3 and Capan-1, were treated with various concentrations of erlotinib, the specific mitogen-activated protein kinase kinase (MEK) inhibitor U0126, and protein kinase B (AKT) inhibitor XIV. DNA synthesis was measured by 5-bromo-2'-deoxyuridine (BrdU) assays. Expression and phosphorylation of the epidermal growth factor receptor (EGFR) and downstream signaling molecules were quantified by Western blot analysis. The data were processed to calibrate a mathematical model, based on ordinary differential equations, describing the EGFRmediated signal transduction. RESULTS:Erlotinib significantly inhibited BrdU incorporation in BxPC-3 cells at a concentration of 1 mol/L, whereas Capan-1 cells were much more resistant. In both cell lines, MEK inhibitor U0126 and erlotinib attenuated DNA synthesis in a cumulative manner, whereas the AKT pathway-specific inhibitor did not enhance the effects of erlotinib. While basal phosphorylation of EGFR and extracellular signal-regulated kinase (ERK) did not differ much between the two cell lines, BxPC-3 cells displayed a more than five-times higher basal phospho-AKT level than Capan-1 cells. Epidermal growth factor (EGF) at 10 ng/mL induced the phosphorylation of EGFR, AKT and ERK in both cell lines with similar kinetics. In BxPC-3 cells, higher levels of phospho-AKT and phospho-ERK (normalized to the total protein levels) were observed. Independent of the cell line, erlotinib efficiently inhibited phosphorylation of EGFR, AKT and ERK. The mathematical model successfully simulated the experimental findings and provided predictions regarding phosphoprotein levels that could be verified experimentally. CONCLUSION:Our data suggest basal AKT phosphorylation and the degree of EGF-induced activation of AKT and ERK as molecular determinants of erlotinib efficiency in PC cells.展开更多
Intramuscular fat (IMF) content in chickens significantly contributes to meat quality. The main objective of this study was to assess the expression of calcineudn (CAN) and Ca^2+/calmodutin-dependent protein kina...Intramuscular fat (IMF) content in chickens significantly contributes to meat quality. The main objective of this study was to assess the expression of calcineudn (CAN) and Ca^2+/calmodutin-dependent protein kinase (CAME) in lipogene- sis in chicken muscle. The chickens were slaughtered and sampled at the ages of 4, 8, and 16 weeks, respectively. IMF content and the expression of CaN subunits and CaMK isoforms were measured in thigh muscle tissue. The results showed that the IMF contents were higher in chickens at the age of 16 weeks compared with those in chickens at the ages of 4 and 8 weeks (P〈0.05). The expression levels of fatty acid synthase (FAS) and fatty acid translocase CD36 (FAT/CD36) mRNA in 16-week-old chickens were all significantly up-regulated compared with those in 4-week-old chickens (P〈0.05). The mRNA levels of CaNB and CaMK IV in 16-week-old chickens were significantly lower than those in 4-week-old chickens (P〈0.05). But the CaMK II mRNA levels in 16-week-old chickens were significantly higher than those in 4-week-old chickens (P〈0.05). To investigate the roles of CaMK and CaN in adipogenesis, SV cells were incubated in standard adipogenesis medium for 24 h and treated with specific inhibitor of CaMK and CaN. The ex- pressions of CCAAT/enhancer binding protein β(C/EBPJ3), sterol regulatory element- binding protein 1 (SREBP1) and peroxisome proliferation-activated receptor ), (PPARy) were dramatically enhanced by CsA and CaN inhibitor (P〈0.05). KN93, a CaMK Ⅱ inhibitor, dramatically repressed the expression of those lipogenic genes (P〈0.05). All the results above indicated that CaN and CaMK had different effects on adipogenesis in the muscle of chickens.展开更多
基金National Institutes of Health, Grant CA83719US Department of Veterans Affairs
文摘This review summarizes the current state of knowledge regarding the role of endothelial dysfunction in the pathogenesis of early and delayed intestinal radiation toxicity and discusses various endothelial-oriented interventions aimed at reducing the risk of radiation enteropathy. Studies published in the biomedical literature during the past four decades and cited in PubMed, as well as clinical and laboratory data from our own research program are reviewed. The risk of injury to normal tissues limits the cancer cure rates that can be achieved with radiation therapy. During treatment of abdominal and pelvic tumors, the intestine is frequently a major close-limiting factor. Microvascular injury is a prominent feature of both early (inflammatory), as well as delayed (fibroproliferative) radiation injuries in the intestine and in many other normal tissues. Evidence from our and other laboratories suggests that endothelial dysfunction, notably a deficiency of endothelial thrombomodulin, plays a key role in the pathogenesis of these radiation responses. Deficient levels of thrombomodulin cause loss of vascular thromboresistance, excessive activation of cellular thrombin receptors by thrombin, and insufficient activation of protein C, a plasma protein with anticoagulant, anti-inflammatory, and cytoprotective properties. These changes are presumed to be critically involved in many aspects of early intestinal radiation toxicity and may sustain the fibroproliferative processes that lead to delayed intestinal dysfunction, fibrosis, and clinical complications. In conclusion, injury of vascular endothelium is important in the pathogenesis of the intestinal radiation response. Endothelial-oriented interventions are appealing strategies to prevent or treat normal tissue toxicity associated with radiation treatment of cancer.
基金supported by the National Natural Foundation of China(81160302)the Major Research Project of Yunnan Province(2011FZ109)Research project of Yunnan Education Bureau(2014Y153)
文摘Here,we used reverse transcription-PCR(RT-PCR) and western blot to detect protease-activated receptor(PAR) 1,PAR 2 and PAR 4 expression in cancer tissues and cell lines of esophageal squamous cell carcinoma,and investigated the co-relationship between PAR expression and clinic-pathological data for esophageal cancer.The methylation of PAR4 gene promoter involved in esophageal carcinoma was also analyzed.By comparing the mRNA expressions of normal esophageal tissue and human esophageal epithelial cells(HEEpiC),we found that among the 28 cases of esophageal squamous cell carcinoma,PAR1(60%) and PAR2(71%) were elevated in 17 and 20 cases,respectively,and PAR4(68%) expression was lowered in 19 cases.Whereas,in human esophageal squamous cells(TE-1 and TE-10),PAR1 and PAR2 expression was increased but PAR4 was decreased.Combined with clinical data,the expression of PAR1 in poorly differentiated(P=0.016) and middle and lower parts of the esophagus(P=0.016) was higher; expression of PAR4 in poorly differentiated carcinoma was lower(P=0.049).Regarding TE-1 and TE-10 protein expression,we found that in randomized esophageal carcinoma,PAR1(P=0.027) and PAR2(P=0.039) expressions were increased,but lowered for PAR4(P=0.0001).In HEEpiC,TE-1,TE-10,esophageal and normal esophagus tissue samples(case No.7),the frequency of methylation at the 19 CpG loci of PAR4 was 35.4%,95.2%,83.8%,62.6% and 48.2%,respectively.Our results indicate that the expression of PAR1 and PAR2 in esophageal squamous cell carcinoma is increased but PAR4 is decreased.Hypermethylation of the promoter of the PAR4 gene may contribute to reduced expression of PAR4 in esophageal squamous cell carcinoma.
基金Supported by The Zhejiang Extremely Key Subject of SurgeryThe Wenzhou Key Laboratory Project in Surgery
文摘AIM: To investigate the mechanism of interleukin (IL)-6 secretion through blocking the IL-17A/IL-17A recepto (IL-17RA) signaling pathway with a short hairpin RNA (shRNA) in hepatic stellate cells (HSCs) in vitro . METHODS: HSCs were derived from the livers of adul male Sprague-Dawley rats. IL-6 expression was evalu ated using real-time quantitative polymerase chain reaction and enzyme linked immunosorbent assay. The phosphorylation activity of p38 mitogen activated pro tein kinases (MAPK) and extracellular regulated pro tein kinases (ERK) 1/2 upon induction by IL-17A and suppression by IL-17RA shRNA were examined using Western blotting.RESULTS: IL-6 expression induced by IL-17A was significantly increased compared to control in HSCs (P < 0.01 in a dose-dependent manner). Suppression of IL17RA using lentiviral-mediated shRNA inhibited IL-6 expression induced by IL-17A compared to group with only IL-17A treatment (1.44 ± 0.17 vs 4.07 ± 0.43, P < 0.01). IL-17A induced rapid phosphorylation of p38 MAPK and ERK1/2 after 5 min exposure, and showed the strongest levels of phosphorylation of p38 MAPK and ERK1/2 at 15 min in IL-17A-treated HSCs. IL-6 mRNA expression induced by IL-17A (100 ng/mL) for 3 h exposure was inhibited by preincubation with specific inhibitors of p38 MAPK (SB-203580) and ERK1/2 (PD-98059) compared to groups without inhibitors preincubation (1.67 ± 0.24, 2.01 ± 0.10 vs 4.08 ± 0.59, P < 0.01). Moreover, lentiviral-mediated IL-17RA shRNA 1 inhibited IL-17A-induced IL-6 mRNA expression compared to random shRNA in HSCs (1.44 ± 0.17 vs 3.98 ± 0.68, P < 0.01). Lentiviral-mediated IL17RA shRNA 1 inhibited phosphorylation of p38 MAPK and ERK1/2 induced by 15 min IL-17A (100 ng/mL) exposure. CONCLUSION: Down-regulation of the IL-17RA receptor by shRNA decreased IL-6 expression induced by IL-17A via p38 MAPK and ERK1/2 phosphorylation in HSCs. Suppression of IL-17RA expression may be a strategy to reduce the inflammatory response induced by IL-17A in the liver.
基金Supported by A grant of the Bundesministerium für Bildung und Forschung through the FORSYS partner program, No.0315255the Helmholtz Society as part of the Systems Biology Network
文摘AIM:To gain insights into the molecular action of erlotinib in pancreatic cancer (PC) cells. METHODS:Two PC cell lines, BxPC-3 and Capan-1, were treated with various concentrations of erlotinib, the specific mitogen-activated protein kinase kinase (MEK) inhibitor U0126, and protein kinase B (AKT) inhibitor XIV. DNA synthesis was measured by 5-bromo-2'-deoxyuridine (BrdU) assays. Expression and phosphorylation of the epidermal growth factor receptor (EGFR) and downstream signaling molecules were quantified by Western blot analysis. The data were processed to calibrate a mathematical model, based on ordinary differential equations, describing the EGFRmediated signal transduction. RESULTS:Erlotinib significantly inhibited BrdU incorporation in BxPC-3 cells at a concentration of 1 mol/L, whereas Capan-1 cells were much more resistant. In both cell lines, MEK inhibitor U0126 and erlotinib attenuated DNA synthesis in a cumulative manner, whereas the AKT pathway-specific inhibitor did not enhance the effects of erlotinib. While basal phosphorylation of EGFR and extracellular signal-regulated kinase (ERK) did not differ much between the two cell lines, BxPC-3 cells displayed a more than five-times higher basal phospho-AKT level than Capan-1 cells. Epidermal growth factor (EGF) at 10 ng/mL induced the phosphorylation of EGFR, AKT and ERK in both cell lines with similar kinetics. In BxPC-3 cells, higher levels of phospho-AKT and phospho-ERK (normalized to the total protein levels) were observed. Independent of the cell line, erlotinib efficiently inhibited phosphorylation of EGFR, AKT and ERK. The mathematical model successfully simulated the experimental findings and provided predictions regarding phosphoprotein levels that could be verified experimentally. CONCLUSION:Our data suggest basal AKT phosphorylation and the degree of EGF-induced activation of AKT and ERK as molecular determinants of erlotinib efficiency in PC cells.
基金Supported by Natural Science Foundation of Hubei Province of China(2011CDB012)Project of State Key Laboratory of Animal Nutrition(2004DA125184F1012)
文摘Intramuscular fat (IMF) content in chickens significantly contributes to meat quality. The main objective of this study was to assess the expression of calcineudn (CAN) and Ca^2+/calmodutin-dependent protein kinase (CAME) in lipogene- sis in chicken muscle. The chickens were slaughtered and sampled at the ages of 4, 8, and 16 weeks, respectively. IMF content and the expression of CaN subunits and CaMK isoforms were measured in thigh muscle tissue. The results showed that the IMF contents were higher in chickens at the age of 16 weeks compared with those in chickens at the ages of 4 and 8 weeks (P〈0.05). The expression levels of fatty acid synthase (FAS) and fatty acid translocase CD36 (FAT/CD36) mRNA in 16-week-old chickens were all significantly up-regulated compared with those in 4-week-old chickens (P〈0.05). The mRNA levels of CaNB and CaMK IV in 16-week-old chickens were significantly lower than those in 4-week-old chickens (P〈0.05). But the CaMK II mRNA levels in 16-week-old chickens were significantly higher than those in 4-week-old chickens (P〈0.05). To investigate the roles of CaMK and CaN in adipogenesis, SV cells were incubated in standard adipogenesis medium for 24 h and treated with specific inhibitor of CaMK and CaN. The ex- pressions of CCAAT/enhancer binding protein β(C/EBPJ3), sterol regulatory element- binding protein 1 (SREBP1) and peroxisome proliferation-activated receptor ), (PPARy) were dramatically enhanced by CsA and CaN inhibitor (P〈0.05). KN93, a CaMK Ⅱ inhibitor, dramatically repressed the expression of those lipogenic genes (P〈0.05). All the results above indicated that CaN and CaMK had different effects on adipogenesis in the muscle of chickens.