Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus m...Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats.展开更多
Hepatocellular carcinoma(HCC) is the third leading cause of cancer-related deaths worldwide. Only 30%-40% of the patients with HCC are eligible for curative treatments, which include surgical resection as the first op...Hepatocellular carcinoma(HCC) is the third leading cause of cancer-related deaths worldwide. Only 30%-40% of the patients with HCC are eligible for curative treatments, which include surgical resection as the first option, liver transplantation and percutaneous ablation. Unfortunately, there is a high frequency of tumor recurrence after surgical resection and most HCC seem resistant to conventional chemotherapy and radiotherapy. Sorafenib, a multi-tyrosine kinase inhibitor, is the only chemotherapeutic option for patients with advanced hepatocellular carcinoma. Patients treated with Sorafenib have a significant increase in overall survival of about three months. Therefore, there is an urgent need to develop alternative treatments. Due to its role in cell growth and development, the insulin-like growth factor system is commonly deregulated in many cancers. Indeed, the insulin-like growth factor(IGF) axis has recently emerged as a potential target for hepatocellular carcinoma treatment. To this aim, several inhibitors of the pathway have been developed suchas monoclonal antibodies, small molecules, antisense oligonucleotides or small interfering RNAs. However recent studies suggest that, unlike most tumors, HCC development requires increased signaling through insulin growth factor Ⅱ rather than insulin growth factor Ⅰ. This may have great implications in the future treatment of HCC. This review summarizes the role of the IGF axis in liver carcinogenesis and the current status of the strategies designed to target the IGF-Ⅰ signaling pathway for hepatocellular carcinoma treatment.展开更多
AIM: To study the expression level and localization of insulin-like growth factor -I receptor (IGF-IR) in HepG2 cells and Chang liver cells, and to observe the effect of anti-IGF-IR monoclonal antibody (αIR3) on the ...AIM: To study the expression level and localization of insulin-like growth factor -I receptor (IGF-IR) in HepG2 cells and Chang liver cells, and to observe the effect of anti-IGF-IR monoclonal antibody (αIR3) on the growth of HepG2 cells. METHODS: The expression of IGF-IR in HepG2 cells and Chang liver cells was detected by immunohistochemistry. The influences of aIR3 on proliferation and apoptosis were examined by the 3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and electron microscopy, respectively. Flow cytometry (FCM) was applied for the analysis of cell cycle and apoptosis was observed under electron microscope. RESULTS: IGF-IR was located in the membranes of both HepG2 and Chang liver cell lines, and the expression level of IGF-IR was higher in HepG2 cells than in Chang liver cells. Treated with 0.1μg/mLαIR3 for 48 h in vitro, the cell growth index (GI) of HepG2 cells was significantly higher than that of control (103.41% vs 100%, P<0.01). However, the aIR3 for 24 h at final concentration of 4.0μg/mL made the GI of HepG2 cells lower than that of control (93.37% vs 100%, P < 0.01). Compared with control, treated with aIR3 for 48 h at final concentrations ranging from 1.0μg/mL to 4.0μg/mL markedly reduced the GIs of HepG2 cells (97.63%, 97.16%, 95.13%, 92.53% vs 100%, P < 0.05 or P < 0.01), treated withαIR3 for 72 h at final concentrations ranging from 0.2μg/mL to 4.0μg/mL decreased the GIs of HepG2 cells obviously (95%, 91.63%, 90.77%, 89.84%, 88.51% vs 100%, P<0.01), and treated with aIR3 for 96 h at final concentrations ranging from 0.5μg/mL to 4.0μg/mL made GIs of HepG2 cells lower significantly (88.86%, 83.97%, 79.81%, 77.24%, 70.51% vs 100%, P<0.05 or P<0.01). Moreover, treated withαIR3 from 24 h to 96 h at final concentrations ranging from 0.2μg/mL to 4.0μg/mL reduced the GI of HepG2 cells from 97.63% to 70.51% in a dose- and time-dependent manner. Also,αIR3 treatment for 72 h at final concentration from 0.5μg/mL to 2.0μg/mL increased the proportion of G0/G1 phase cells(61.73%, 67.1%, 83.7%,76.87% vs 44.47%, P<0.01) and significantly decreased that of S phase cells(28.63%, 25.13%, 15.63%, 23.13% vs 53.17%, P<0.01), in contrast to the proportion of G2/M phase cells. The apoptotic rates of HepG2 cells were increased more than that of control (7.83%, 16.13%, 21.1%, 37.73% vs 4.13%, P< 0.01). CONCLUSION: The malignant cell phenotype of human hepatocarcinoma cell is related to overexpression of IGF-IR. The blockage of IGF-IR with aaaaaIR3 may contribute to the inhibition of proliferation and induction of apoptosis in HepG2 cells.展开更多
基金sponsored by the Natural Science Foundation of Hebei Province,H2012406018,H2013406096a grant from Hebei Province Department of Education,No.2006301
文摘Previous studies have shown that sericin extracted from silk cocoon significantly reduces blood glucose levels and protects the nervous system against diabetes mellitus. In this study, a rat type 2 diabetes mellitus model was established by intraperitoneal injection of 25 mg/kg streptozotocin for 3 successive days, following which the rats were treated with sericin for 35 days. After treatment, the blood glucose levels of the diabetic rats decreased significantly, the growth hormone level in serum and its expression in the hippocampus decreased significantly, while the insulin-like growth factor-1 level in serum and insulin-like growth factor-1 and growth hormone receptor expression in the hippocampus increased significantly. The experimental findings indicate that sericin improves disorders of the growth hormone/insulin-like growth factor 1 axis to alleviate hippocampal damage in diabetic rats.
基金Supported by Ministerio de Ciencia e Innovacion BIO2009/09295 and SAF2012-40003FEDER funding,funds from the"UTE project CIMA"+1 种基金the project RNAREG(CSD2009-00080)from The Ministry of Science and Innovation under the programme CONSOLIDER INGENIO 2010
文摘Hepatocellular carcinoma(HCC) is the third leading cause of cancer-related deaths worldwide. Only 30%-40% of the patients with HCC are eligible for curative treatments, which include surgical resection as the first option, liver transplantation and percutaneous ablation. Unfortunately, there is a high frequency of tumor recurrence after surgical resection and most HCC seem resistant to conventional chemotherapy and radiotherapy. Sorafenib, a multi-tyrosine kinase inhibitor, is the only chemotherapeutic option for patients with advanced hepatocellular carcinoma. Patients treated with Sorafenib have a significant increase in overall survival of about three months. Therefore, there is an urgent need to develop alternative treatments. Due to its role in cell growth and development, the insulin-like growth factor system is commonly deregulated in many cancers. Indeed, the insulin-like growth factor(IGF) axis has recently emerged as a potential target for hepatocellular carcinoma treatment. To this aim, several inhibitors of the pathway have been developed suchas monoclonal antibodies, small molecules, antisense oligonucleotides or small interfering RNAs. However recent studies suggest that, unlike most tumors, HCC development requires increased signaling through insulin growth factor Ⅱ rather than insulin growth factor Ⅰ. This may have great implications in the future treatment of HCC. This review summarizes the role of the IGF axis in liver carcinogenesis and the current status of the strategies designed to target the IGF-Ⅰ signaling pathway for hepatocellular carcinoma treatment.
基金Supported by the Gansu Province's Natural Science Fund, No.ZS021-A25-079-Y
文摘AIM: To study the expression level and localization of insulin-like growth factor -I receptor (IGF-IR) in HepG2 cells and Chang liver cells, and to observe the effect of anti-IGF-IR monoclonal antibody (αIR3) on the growth of HepG2 cells. METHODS: The expression of IGF-IR in HepG2 cells and Chang liver cells was detected by immunohistochemistry. The influences of aIR3 on proliferation and apoptosis were examined by the 3- (4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) assay and electron microscopy, respectively. Flow cytometry (FCM) was applied for the analysis of cell cycle and apoptosis was observed under electron microscope. RESULTS: IGF-IR was located in the membranes of both HepG2 and Chang liver cell lines, and the expression level of IGF-IR was higher in HepG2 cells than in Chang liver cells. Treated with 0.1μg/mLαIR3 for 48 h in vitro, the cell growth index (GI) of HepG2 cells was significantly higher than that of control (103.41% vs 100%, P<0.01). However, the aIR3 for 24 h at final concentration of 4.0μg/mL made the GI of HepG2 cells lower than that of control (93.37% vs 100%, P < 0.01). Compared with control, treated with aIR3 for 48 h at final concentrations ranging from 1.0μg/mL to 4.0μg/mL markedly reduced the GIs of HepG2 cells (97.63%, 97.16%, 95.13%, 92.53% vs 100%, P < 0.05 or P < 0.01), treated withαIR3 for 72 h at final concentrations ranging from 0.2μg/mL to 4.0μg/mL decreased the GIs of HepG2 cells obviously (95%, 91.63%, 90.77%, 89.84%, 88.51% vs 100%, P<0.01), and treated with aIR3 for 96 h at final concentrations ranging from 0.5μg/mL to 4.0μg/mL made GIs of HepG2 cells lower significantly (88.86%, 83.97%, 79.81%, 77.24%, 70.51% vs 100%, P<0.05 or P<0.01). Moreover, treated withαIR3 from 24 h to 96 h at final concentrations ranging from 0.2μg/mL to 4.0μg/mL reduced the GI of HepG2 cells from 97.63% to 70.51% in a dose- and time-dependent manner. Also,αIR3 treatment for 72 h at final concentration from 0.5μg/mL to 2.0μg/mL increased the proportion of G0/G1 phase cells(61.73%, 67.1%, 83.7%,76.87% vs 44.47%, P<0.01) and significantly decreased that of S phase cells(28.63%, 25.13%, 15.63%, 23.13% vs 53.17%, P<0.01), in contrast to the proportion of G2/M phase cells. The apoptotic rates of HepG2 cells were increased more than that of control (7.83%, 16.13%, 21.1%, 37.73% vs 4.13%, P< 0.01). CONCLUSION: The malignant cell phenotype of human hepatocarcinoma cell is related to overexpression of IGF-IR. The blockage of IGF-IR with aaaaaIR3 may contribute to the inhibition of proliferation and induction of apoptosis in HepG2 cells.
