AIM: To investigate whether NF-kB is activated in human gastric carcinoma tissues and, if so, to study whether there is any correlation between NF-kB activity and heparanase expression in gastric carcinoma. METHODS: N...AIM: To investigate whether NF-kB is activated in human gastric carcinoma tissues and, if so, to study whether there is any correlation between NF-kB activity and heparanase expression in gastric carcinoma. METHODS: NF-kB activation was assayed by immunohistochemical staining in formalin-fixed, paraffin-embedded specimens from 45 gastric carcinoma patients. Electrophoretic mobility shift assay (EMSA) method was used for nuclear protein from these fresh tissue specimens. Heparanase gene expression was quantified using quantitative RT-PCR. RESULTS: The nuclear translocation of RelA (marker of NF-kB activation) was significantly higher in tumor cells compared to adjacent and normal epithelial cells [(41.3±3.52)% vs (0.38±0.22) %, t=10.993, P= 0.000<0.05; (41.3±3.52)% vs(0±0.31)%, t=11.484, P= 0.000<0.05]. NF-kB activation was correlated with tumor invasion-related clinicopathological features such as lymphatic invasion, pathological stage, and depth of invasion (Z= 2.148, P= 0.032<0.05; t = 8.758, P= 0.033<0.05; t = 18.531, P = 0.006<0.05). NF-KB activation was significantly correlated with expression of heparanase gene (r= 0.194, P=0.046<0.05). CONCLUSION: NF-KB RelA (p65) activation was related with increased heparanase gene expression and correlated with poor clinicopathological characteristics in gastric cancers. This suggests NF-kB as a major controller of the metastatic phenotype through its reciprocal regulation of some metastasis-related genes.展开更多
AIM: Heparanase degrades heparan sulfate proteoglycans (HSPGs) and is a critical mediator of tumor metastasis and angiogenesis. Recently, it has been cloned as a single gene family and found to be a potential target f...AIM: Heparanase degrades heparan sulfate proteoglycans (HSPGs) and is a critical mediator of tumor metastasis and angiogenesis. Recently, it has been cloned as a single gene family and found to be a potential target for antimetastasis drugs. However, the molecular basis for the regulation of heparanase expression is still not quite clear. The aim of this study was to determine whether the expression of eukaryotic initiation factor 4E (eIF-4E) correlated with the heparanase level in tumor cells and to explore the correlation between heparanase expression and metastatic potential of LS- 174T cells.METHODS: A 20-met antisense s-oligodeoxynucleotide (asODN) targeted against the translation start site of eIF-4E mRNA was introduced into LS-174T cells by lipid-mediated DNA-transfection. eIF-4E protein and mRNA levels were detected by Western blot analysis and RT-PCR, respectively.Heparanase activity was defined as the ability to degrade high molecular weight (40-100 kDa) radiolabeled HS (heparan sulfate) substrate into low molecular weight (5-15 kDa) HS fragments that could be differentiated by gel filtration chromatography. The invasive potential of tumor cell in vitro was observed by using a Matrigel invasion assay system.RESULTS: The 20-mer asODN against eIF-4E specifically and significantly inhibited eIF-4E expression at both transcriptional and translational levels. As a result, the expression and activity of heparanase were effectively retarded and the decreased activity of heparanase resulted in the decreased invasive potential of LS-174T.CONCLUSION: eIF-4E is involved in the regulation of heparanase production in colon adenocarcinoma cell line LS-174T, and its critical function makes it a particularly interesting target for heparanase regulation. This targeting strategy in antisense chemistry may have practical applications in experimental or clinical anti-metastatic gene therapy of human colorectal carcinoma.展开更多
The novel heparinase-producing bacterial strain Sphingobacterium sp. was isolated and screened from soil. The optimum medium composition is （g/L）: Soytone 20, NaCl 1, K2HPO4 2.5, MgSO4 0.5, Heparin 2, Sucrose 15, pH...The novel heparinase-producing bacterial strain Sphingobacterium sp. was isolated and screened from soil. The optimum medium composition is （g/L）: Soytone 20, NaCl 1, K2HPO4 2.5, MgSO4 0.5, Heparin 2, Sucrose 15, pH 7.5. The optimum temperature for growth and enzyme production was 32℃. When cultured at a rotating shaker at 30℃ for 36 hours, 200r/min, 50mL medium in 500mL flask, the production of heparinase reached 4000U/L.展开更多
文摘AIM: To investigate whether NF-kB is activated in human gastric carcinoma tissues and, if so, to study whether there is any correlation between NF-kB activity and heparanase expression in gastric carcinoma. METHODS: NF-kB activation was assayed by immunohistochemical staining in formalin-fixed, paraffin-embedded specimens from 45 gastric carcinoma patients. Electrophoretic mobility shift assay (EMSA) method was used for nuclear protein from these fresh tissue specimens. Heparanase gene expression was quantified using quantitative RT-PCR. RESULTS: The nuclear translocation of RelA (marker of NF-kB activation) was significantly higher in tumor cells compared to adjacent and normal epithelial cells [(41.3±3.52)% vs (0.38±0.22) %, t=10.993, P= 0.000<0.05; (41.3±3.52)% vs(0±0.31)%, t=11.484, P= 0.000<0.05]. NF-kB activation was correlated with tumor invasion-related clinicopathological features such as lymphatic invasion, pathological stage, and depth of invasion (Z= 2.148, P= 0.032<0.05; t = 8.758, P= 0.033<0.05; t = 18.531, P = 0.006<0.05). NF-KB activation was significantly correlated with expression of heparanase gene (r= 0.194, P=0.046<0.05). CONCLUSION: NF-KB RelA (p65) activation was related with increased heparanase gene expression and correlated with poor clinicopathological characteristics in gastric cancers. This suggests NF-kB as a major controller of the metastatic phenotype through its reciprocal regulation of some metastasis-related genes.
基金the National Natural Science Foundation of China,No.30171053
文摘AIM: Heparanase degrades heparan sulfate proteoglycans (HSPGs) and is a critical mediator of tumor metastasis and angiogenesis. Recently, it has been cloned as a single gene family and found to be a potential target for antimetastasis drugs. However, the molecular basis for the regulation of heparanase expression is still not quite clear. The aim of this study was to determine whether the expression of eukaryotic initiation factor 4E (eIF-4E) correlated with the heparanase level in tumor cells and to explore the correlation between heparanase expression and metastatic potential of LS- 174T cells.METHODS: A 20-met antisense s-oligodeoxynucleotide (asODN) targeted against the translation start site of eIF-4E mRNA was introduced into LS-174T cells by lipid-mediated DNA-transfection. eIF-4E protein and mRNA levels were detected by Western blot analysis and RT-PCR, respectively.Heparanase activity was defined as the ability to degrade high molecular weight (40-100 kDa) radiolabeled HS (heparan sulfate) substrate into low molecular weight (5-15 kDa) HS fragments that could be differentiated by gel filtration chromatography. The invasive potential of tumor cell in vitro was observed by using a Matrigel invasion assay system.RESULTS: The 20-mer asODN against eIF-4E specifically and significantly inhibited eIF-4E expression at both transcriptional and translational levels. As a result, the expression and activity of heparanase were effectively retarded and the decreased activity of heparanase resulted in the decreased invasive potential of LS-174T.CONCLUSION: eIF-4E is involved in the regulation of heparanase production in colon adenocarcinoma cell line LS-174T, and its critical function makes it a particularly interesting target for heparanase regulation. This targeting strategy in antisense chemistry may have practical applications in experimental or clinical anti-metastatic gene therapy of human colorectal carcinoma.
文摘The novel heparinase-producing bacterial strain Sphingobacterium sp. was isolated and screened from soil. The optimum medium composition is （g/L）: Soytone 20, NaCl 1, K2HPO4 2.5, MgSO4 0.5, Heparin 2, Sucrose 15, pH 7.5. The optimum temperature for growth and enzyme production was 32℃. When cultured at a rotating shaker at 30℃ for 36 hours, 200r/min, 50mL medium in 500mL flask, the production of heparinase reached 4000U/L.
