AIM: To investigate the difference in activation of STAT3 signaling between two human stomach adenocarcinoma cell lines: 5-fluorouracil resistant cell line and its parental cell line, and to evaluate its relationship ...AIM: To investigate the difference in activation of STAT3 signaling between two human stomach adenocarcinoma cell lines: 5-fluorouracil resistant cell line and its parental cell line, and to evaluate its relationship with the expression of vascular endothelial growth factor (VEGF). METHODS: Western blot and electrophoretic mobility shift assay (EMSA) were used to detect the expression of phospho-STAT3 protein and constitutive activation of STAT3 in two human stomach adenocarcinoma cell lines, 5-fluorouracil resistant cell line SGC7901/R and its parental cell line SGC7901, respectively. The mRNA expression of VEGF was analysed by semi-quantitative RT-PCR. The expressive intensity of VEGF protein was measured by immunocytochemistry. RESULTS: The expressions of phospho-STATS protein and constitutive activation of STAT3 between two human stomach adenocarcinoma cell lines were different. Compared with the parental cell line SGC7901, the STAT3DNA binding activity and the expressive intensity of phospho-STAT3 protein were lower in the drug-resistant cell line SGC7901/R. The expression levels of VEGF mRNA and its encoded protein were also decreased in drugresistant cell line. CONCLUSION: Over-expression of VEGF may be correlated with elevated STAT3 activation in parental cell line. Lower VEGF expression may be correlated with decreased STAT3 activation in resistant cell line, which may have resulted from negative feedback regulation of STAT signaling.展开更多
AIM： To reverse the multidrug resistance （MDR） by RNA interference （RNAi）-mediated MDRI suppression in heparoma cells.METHODS： For reversing MDR by RNAi technology, two different short hairpin RNAs （shRNAs） we...AIM： To reverse the multidrug resistance （MDR） by RNA interference （RNAi）-mediated MDRI suppression in heparoma cells.METHODS： For reversing MDR by RNAi technology, two different short hairpin RNAs （shRNAs） were designed and constructed into pGenSil-1 plasmid, respectively. They were then transfected into a highly adriarnycin-resistant HepG2 hepatorna cell line （HepG2/ADM）. The RNAi effect on MDR was evaluated by real-time PCR, cell cytotoxicity assay and rhodarnine 123 （Rh123） efflux assy. RESULTS： The stably-transfected clones showed various degrees of reversal of MDR phenotype. Surprisingly, the MDR phenotype was completely reversed in two transfected clones. CONCLUSION： MDR can be reversed by the shRNAmediated MDRI suppression in HepG2/ADM cells, which provides a valuable clue to make multidrug-resistant hepatoma cells sensitive to anti-cancer drugs.展开更多
Adiponectin(APN),a novel hormone/cytokine derived from adipocyte tissue,is involved in various physiological functions. Genetics,nutrition,and adiposity are factors contributing to circulating plasma concentrations of...Adiponectin(APN),a novel hormone/cytokine derived from adipocyte tissue,is involved in various physiological functions. Genetics,nutrition,and adiposity are factors contributing to circulating plasma concentrations of APN.Clinical correlation studies have shown that lower levels of serum APN are associated with increased malignancy of various cancers,such as breast and colon cancers,suggesting that APN has a role in tumorigenesis.APN affects insulin resistance,thus further influencing cancer development. Tumor cells may express receptors for APN.Cellular signaling is the mechanism by which APN exerts its host-protective responses. These factors suggest that serum APN levels and downstream signaling targets of APN may serve as potential diagnostic markers for malignancies.Further research is necessary to clarify the exact role of APN in cancer diagnosis and therapy.展开更多
The above therapeutic results show that TCM drugs have excellent effects in counteracting the metastasis of tumors. They can produce a synergistic effect when used together with surgery, radio- and chemotherapy. In an...The above therapeutic results show that TCM drugs have excellent effects in counteracting the metastasis of tumors. They can produce a synergistic effect when used together with surgery, radio- and chemotherapy. In analyzing the relationship between the factors that affect the distant metastasis, the authors strongly recommend that the FDM-survival rate be used, i.e. the survival rate free from distant metastasis as suggested by Hong Minghuang et al in their article. An analysis based on FDM-survival rate in a duration of three or five years with the data treated with the Kaplan-Meier and/or Life Table would be rational and convincible.展开更多
基金Supported by Shanghai Education Committee Foundation, No.024119114
文摘AIM: To investigate the difference in activation of STAT3 signaling between two human stomach adenocarcinoma cell lines: 5-fluorouracil resistant cell line and its parental cell line, and to evaluate its relationship with the expression of vascular endothelial growth factor (VEGF). METHODS: Western blot and electrophoretic mobility shift assay (EMSA) were used to detect the expression of phospho-STAT3 protein and constitutive activation of STAT3 in two human stomach adenocarcinoma cell lines, 5-fluorouracil resistant cell line SGC7901/R and its parental cell line SGC7901, respectively. The mRNA expression of VEGF was analysed by semi-quantitative RT-PCR. The expressive intensity of VEGF protein was measured by immunocytochemistry. RESULTS: The expressions of phospho-STATS protein and constitutive activation of STAT3 between two human stomach adenocarcinoma cell lines were different. Compared with the parental cell line SGC7901, the STAT3DNA binding activity and the expressive intensity of phospho-STAT3 protein were lower in the drug-resistant cell line SGC7901/R. The expression levels of VEGF mRNA and its encoded protein were also decreased in drugresistant cell line. CONCLUSION: Over-expression of VEGF may be correlated with elevated STAT3 activation in parental cell line. Lower VEGF expression may be correlated with decreased STAT3 activation in resistant cell line, which may have resulted from negative feedback regulation of STAT signaling.
基金Supported by the National Natural Science Foundation of China,No. 30400431
文摘AIM： To reverse the multidrug resistance （MDR） by RNA interference （RNAi）-mediated MDRI suppression in heparoma cells.METHODS： For reversing MDR by RNAi technology, two different short hairpin RNAs （shRNAs） were designed and constructed into pGenSil-1 plasmid, respectively. They were then transfected into a highly adriarnycin-resistant HepG2 hepatorna cell line （HepG2/ADM）. The RNAi effect on MDR was evaluated by real-time PCR, cell cytotoxicity assay and rhodarnine 123 （Rh123） efflux assy. RESULTS： The stably-transfected clones showed various degrees of reversal of MDR phenotype. Surprisingly, the MDR phenotype was completely reversed in two transfected clones. CONCLUSION： MDR can be reversed by the shRNAmediated MDRI suppression in HepG2/ADM cells, which provides a valuable clue to make multidrug-resistant hepatoma cells sensitive to anti-cancer drugs.
基金supported by grants from the National Health and Medical Research Council of Australia Project Grant ID1006200(LH)Cancer Council of New South Wales IG11- 27(LH)+1 种基金Robert W.Storr Bequest to the University of Sydney (LH)an Australian Postgraduate Award(SO)
文摘Adiponectin(APN),a novel hormone/cytokine derived from adipocyte tissue,is involved in various physiological functions. Genetics,nutrition,and adiposity are factors contributing to circulating plasma concentrations of APN.Clinical correlation studies have shown that lower levels of serum APN are associated with increased malignancy of various cancers,such as breast and colon cancers,suggesting that APN has a role in tumorigenesis.APN affects insulin resistance,thus further influencing cancer development. Tumor cells may express receptors for APN.Cellular signaling is the mechanism by which APN exerts its host-protective responses. These factors suggest that serum APN levels and downstream signaling targets of APN may serve as potential diagnostic markers for malignancies.Further research is necessary to clarify the exact role of APN in cancer diagnosis and therapy.
文摘The above therapeutic results show that TCM drugs have excellent effects in counteracting the metastasis of tumors. They can produce a synergistic effect when used together with surgery, radio- and chemotherapy. In analyzing the relationship between the factors that affect the distant metastasis, the authors strongly recommend that the FDM-survival rate be used, i.e. the survival rate free from distant metastasis as suggested by Hong Minghuang et al in their article. An analysis based on FDM-survival rate in a duration of three or five years with the data treated with the Kaplan-Meier and/or Life Table would be rational and convincible.
