Human mesenchymal stem cells （hMSCs） can home to tumor sites and inhibit the growth of tumor cells. Little is known about the underlying molecular mechanisms that link hMSCs to the targeted inhibition of tumor cells...Human mesenchymal stem cells （hMSCs） can home to tumor sites and inhibit the growth of tumor cells. Little is known about the underlying molecular mechanisms that link hMSCs to the targeted inhibition of tumor cells. In this study, we investigated the effects of hMSCs on two human hepatoma cell lines （H7402 and HepG2） using an animal transplantation model, a co-culture system and conditioned media from hMSCs. Animal transplantation studies showed that the latent time for tumor formation was prolonged and that the tumor size was smaller when SCID mice were injected with H7402 cells and an equal number of Z3 hMSCs. When co-cultured with Z3 cells, H7402 cell proliferation decreased, apoptosis increased, and the expression of Bcl-2, c-Myc, proliferating cell nuclear antigen （PCNA） and survivin was downregulated. After treatment with conditioned media derived from Z3 hMSC cultures, H4702 cells showed decreased colony-forming ability and decreased proliferation. Immunoblot analysis showed that β-catenin, Bcl-2, c-Myc, PCNA and survivin expression was downregulated in H7402 and HepG2 cells. Taken together, our findings demonstrate that hMSCs inhibit the malignant phenotypes of the H7402 and HepG2 human liver cancer cell lines, which include proliferation, colony-forming ability and oncogene expression both in vitro and in vivo. Furthermore, our studies provide evidence that the Wnt signaling pathway may have a role in hMSC-mediated targeting and tumor cell inhibition.展开更多
Gastric cancer remains one of the most common cancers worldwide and one of the leading cause for cancerrelated deaths. Gastric adenocarcinoma is a multifactorial disease that is genetically, cytologically and architec...Gastric cancer remains one of the most common cancers worldwide and one of the leading cause for cancerrelated deaths. Gastric adenocarcinoma is a multifactorial disease that is genetically, cytologically and architecturally more heterogeneous than other gastrointestinal carcinomas.The aberrant activation of the Wnt/β-catenin signaling pathway is involved in the development and progression of a significant proportion of gastric cancer cases. This review focuses on the participation of the Wnt/b-catenin pathway in gastric cancer by offering an analysis of the relevant literature published in this field. Indeed, it is discussed the role of key factors in Wnt/β-catenin signaling and their downstream effectors regulating processes involved in tumor initiation, tumor growth, metastasis and resistance to therapy. Available data indicate that constitutive Wnt signalling resulting from Helicobacter pylori infection and inactivation of Wnt inhibitors(mainly by inactivating mutations and promoter hypermethylation) play an important role in gastric cancer. Moreover, a number of recent studies confirmed CTNNB1 and APC as driver genes in gastric cancer. The identification of specific membrane, intracellular, and extracellular components of the Wnt pathway has revealed potential targets for gastric cancer therapy. High-throughput "omics" approaches will help in the search for Wnt pathway antagonist in the near future.展开更多
AIM: To observe the gene silencing mediated by the specific shRNA targeted against β-catenin and its effect on cell proliferation and cycle distribution in the human colon cancer cell line Colo205. METHODS: Two shRNA...AIM: To observe the gene silencing mediated by the specific shRNA targeted against β-catenin and its effect on cell proliferation and cycle distribution in the human colon cancer cell line Colo205. METHODS: Two shRNA plasmid vectors against β-catenin were constructed and transfected into Colo205 cells with LipofectamineTM2000. The down-regulations of β-catenin, c-myc and cyclinD1 expressions were detected by RT-PCR and western blot analysis. The cell proliferation inhibitions were determined by MTT assay and soft agar colony formation assay. The effect of these two β-catenin shRNAs on cell cycle distribution and apoptosis was examined by flow cytometry. RESULTS: These two shRNA vectors targeted against β-catenin efficiently suppressed the expression of β-catenin and its down stream genes, c-myc and cyclinD1. The expression inhibition rates were around 40%-50% either at the mRNA or at the protein level. The shRNA-mediated gene silencing of β-catenin resulted in significant inhibition of cell growth both on the culture plates and in the soft agar. Moreover, the cancer cells showed significant G0/G1 arrest and increased apoptosis at 72 h post transfection due to gene silencing. CONCLUSION: These specific shRNAs targeted against β-catenin could have a gene silencing effect and block the WNT signaling pathway. They could inhibit cell growth, increase apoptosis, and induce cell cycle arrest in Colo205 cells. ShRNA interference against β-catenin is of potential value in gene therapy of colon cancer.展开更多
Objective： To investigate the expressions of caveolin-1, E-cadherin and β-catenin in gastric carcinoma, precancerous gastric and chronic non-atrophic gastritis tissues, and evaluate the correlation of these expressi...Objective： To investigate the expressions of caveolin-1, E-cadherin and β-catenin in gastric carcinoma, precancerous gastric and chronic non-atrophic gastritis tissues, and evaluate the correlation of these expressions with the development of gastric cancer. Methods： The expressions of caveolin-1, E-cadherin and β-catenin were detected by biotin-streptavidinperoxidase （SP） immunohistochemistry on 58 gastric cancer tissues, 40 precancerous gastric tissues and 42 chronic non-atrophic gastritis tissues. The correlation between the expressions of caveolin-1, E-cadherin and β-catenin, and the clinicopathologic parameters of gastric cancer was analyzed retrospectively. Results： The positive rates of caveolin-1 and E-cadherin expressions in gastric carcinoma were significantly lower than precancerous gastric and chronic non-atrophic gastritis tissues （P〈0.01）. An abnormal rate of β-catenin expression in gastric carcinoma was higher than precancerous gastric and chronic non-atrophic gastritis tissues （P〈0.01）. Moreover, low expressions of caveolin-1, E-cadherin and β-catenin correlated with tumor size, depth of invasion, lymph node metastasis and TNM stage （P〈0.05）. The positive rates of caveolin-1 and E-cadherin expressions decreased （P〈0.01）, while an abnormal rate of β-catenin expression increased inversely, with the degree of atypical hyperplasia （P〈0.01）. Caveolin-1 expression correlated positively with E-cadherin （r=0.41, P〈0.05）. Caveolin-1 （r=-0.36, P〈0.05） and E-cadherin （r=-0.45, P〈0.05） expressions negatively correlated with abnormal β-catenin expression. Conclusion： These results suggested that dysregulated expressions of caveolin-1, E-cadherin and β-catenin correlated with the development of gastric cancer and its biological behavior.展开更多
AIM To study the abnormal expression of β-catenin gene and its relationship with invasiveness of primary hepatocellular carcinoma among Chinese people.METHODS Thirty-four hepatocellular carcinoma (HCC) specimens and ...AIM To study the abnormal expression of β-catenin gene and its relationship with invasiveness of primary hepatocellular carcinoma among Chinese people.METHODS Thirty-four hepatocellular carcinoma (HCC) specimens and adjacent para-cancerous tissues, 4 normal liver tissues were immunohistochemically stained to study subcellular distribution of β-catenin. Semiquantitive analysis of expression of β-catenin gene exon 3 mRNA was examined by RT-PCR and in situ hybridization. The relationship between expressions of both β-catenin protein, mRNA and clinicopathological characteristics of HCC was also analyzed.RESULTS Immunohistochemistry showed that all normal liver tissues and para-cancerous tissues examined displayed membranous type staining for β-catenin protein,occasionally with weak expression in the cytoplasm.While 21 cases (61.8%) of HCC examined showed accumulated type in cytoplasms or nuclei. The accumuled type Labling Index (LI) of cancer tissue and paracancarous tissue was (59.9 ± 26.3) and (18.3 ± 9.7)respectively (P＜0.01). Higher accumulated type LI was closely related with invasiveness of HCC. Results of RTPCR showed the β-catenin gene exon 3 mRNA Expression Index (El) of 34 HCCs was higher than that of paracancerous tissue and normal liver tissue. Using in situ hybridization, the signal corresponding to β-catenin gene exon 3 mRNA was particularly strong in cytoplasm of HCC when compared with those of para-cancerous and normal liver tissues. Over expression of β-catenin exon 3 was also found to be correlated with high metastatic potential of HCC.CONCLUSION Abnormal expression of β-catenin gene may contribute importantly to the invasiveness of HCC among Chinese people.展开更多
基金This work was supported by grants from the National Basic Research Program of China （973 Program, No. 2007CB914800 to Xiaodong Zhang）, National Natural Science Foundation of China （No. 30570698 to Xiaodong Zhang） and Tianjin Natural Scientific Foundation （No. 033801211 to Xiaodong Zhang）.
文摘Human mesenchymal stem cells （hMSCs） can home to tumor sites and inhibit the growth of tumor cells. Little is known about the underlying molecular mechanisms that link hMSCs to the targeted inhibition of tumor cells. In this study, we investigated the effects of hMSCs on two human hepatoma cell lines （H7402 and HepG2） using an animal transplantation model, a co-culture system and conditioned media from hMSCs. Animal transplantation studies showed that the latent time for tumor formation was prolonged and that the tumor size was smaller when SCID mice were injected with H7402 cells and an equal number of Z3 hMSCs. When co-cultured with Z3 cells, H7402 cell proliferation decreased, apoptosis increased, and the expression of Bcl-2, c-Myc, proliferating cell nuclear antigen （PCNA） and survivin was downregulated. After treatment with conditioned media derived from Z3 hMSC cultures, H4702 cells showed decreased colony-forming ability and decreased proliferation. Immunoblot analysis showed that β-catenin, Bcl-2, c-Myc, PCNA and survivin expression was downregulated in H7402 and HepG2 cells. Taken together, our findings demonstrate that hMSCs inhibit the malignant phenotypes of the H7402 and HepG2 human liver cancer cell lines, which include proliferation, colony-forming ability and oncogene expression both in vitro and in vivo. Furthermore, our studies provide evidence that the Wnt signaling pathway may have a role in hMSC-mediated targeting and tumor cell inhibition.
文摘Gastric cancer remains one of the most common cancers worldwide and one of the leading cause for cancerrelated deaths. Gastric adenocarcinoma is a multifactorial disease that is genetically, cytologically and architecturally more heterogeneous than other gastrointestinal carcinomas.The aberrant activation of the Wnt/β-catenin signaling pathway is involved in the development and progression of a significant proportion of gastric cancer cases. This review focuses on the participation of the Wnt/b-catenin pathway in gastric cancer by offering an analysis of the relevant literature published in this field. Indeed, it is discussed the role of key factors in Wnt/β-catenin signaling and their downstream effectors regulating processes involved in tumor initiation, tumor growth, metastasis and resistance to therapy. Available data indicate that constitutive Wnt signalling resulting from Helicobacter pylori infection and inactivation of Wnt inhibitors(mainly by inactivating mutations and promoter hypermethylation) play an important role in gastric cancer. Moreover, a number of recent studies confirmed CTNNB1 and APC as driver genes in gastric cancer. The identification of specific membrane, intracellular, and extracellular components of the Wnt pathway has revealed potential targets for gastric cancer therapy. High-throughput "omics" approaches will help in the search for Wnt pathway antagonist in the near future.
基金江苏省2015年度普通高校研究生科研创新计划项目(No KYZZ15-0274)The People Programme(Marie Curie Actions)of the European Union’s Seventh Framework Programme FP7/2007-2013/under REA grant agreement n°PIR SES-GA-2013-612589)+1 种基金江苏省优势学科和江苏省自然科学基金项目(No BK20131415)国家自然科学基金资助项目(No 81503374)
基金Supported by the Guangdong Provincial Scientific Research Grants: No. 2004B30301002, No. 2007B030702012 and No. 04300330
文摘AIM: To observe the gene silencing mediated by the specific shRNA targeted against β-catenin and its effect on cell proliferation and cycle distribution in the human colon cancer cell line Colo205. METHODS: Two shRNA plasmid vectors against β-catenin were constructed and transfected into Colo205 cells with LipofectamineTM2000. The down-regulations of β-catenin, c-myc and cyclinD1 expressions were detected by RT-PCR and western blot analysis. The cell proliferation inhibitions were determined by MTT assay and soft agar colony formation assay. The effect of these two β-catenin shRNAs on cell cycle distribution and apoptosis was examined by flow cytometry. RESULTS: These two shRNA vectors targeted against β-catenin efficiently suppressed the expression of β-catenin and its down stream genes, c-myc and cyclinD1. The expression inhibition rates were around 40%-50% either at the mRNA or at the protein level. The shRNA-mediated gene silencing of β-catenin resulted in significant inhibition of cell growth both on the culture plates and in the soft agar. Moreover, the cancer cells showed significant G0/G1 arrest and increased apoptosis at 72 h post transfection due to gene silencing. CONCLUSION: These specific shRNAs targeted against β-catenin could have a gene silencing effect and block the WNT signaling pathway. They could inhibit cell growth, increase apoptosis, and induce cell cycle arrest in Colo205 cells. ShRNA interference against β-catenin is of potential value in gene therapy of colon cancer.
基金supported by Zhejiang Provincial Natural Science Foundation (No. Y206750)Zhejiang Foundation for Development of Science and Technology, China (No. 2008C33066)Wenzhou Foundation for Development of Science and Technology,China (No. H20060026)
文摘Objective： To investigate the expressions of caveolin-1, E-cadherin and β-catenin in gastric carcinoma, precancerous gastric and chronic non-atrophic gastritis tissues, and evaluate the correlation of these expressions with the development of gastric cancer. Methods： The expressions of caveolin-1, E-cadherin and β-catenin were detected by biotin-streptavidinperoxidase （SP） immunohistochemistry on 58 gastric cancer tissues, 40 precancerous gastric tissues and 42 chronic non-atrophic gastritis tissues. The correlation between the expressions of caveolin-1, E-cadherin and β-catenin, and the clinicopathologic parameters of gastric cancer was analyzed retrospectively. Results： The positive rates of caveolin-1 and E-cadherin expressions in gastric carcinoma were significantly lower than precancerous gastric and chronic non-atrophic gastritis tissues （P〈0.01）. An abnormal rate of β-catenin expression in gastric carcinoma was higher than precancerous gastric and chronic non-atrophic gastritis tissues （P〈0.01）. Moreover, low expressions of caveolin-1, E-cadherin and β-catenin correlated with tumor size, depth of invasion, lymph node metastasis and TNM stage （P〈0.05）. The positive rates of caveolin-1 and E-cadherin expressions decreased （P〈0.01）, while an abnormal rate of β-catenin expression increased inversely, with the degree of atypical hyperplasia （P〈0.01）. Caveolin-1 expression correlated positively with E-cadherin （r=0.41, P〈0.05）. Caveolin-1 （r=-0.36, P〈0.05） and E-cadherin （r=-0.45, P〈0.05） expressions negatively correlated with abnormal β-catenin expression. Conclusion： These results suggested that dysregulated expressions of caveolin-1, E-cadherin and β-catenin correlated with the development of gastric cancer and its biological behavior.
基金National Ninth Five-year Plan of Medical Sciences of China(96-9064)105)
文摘AIM To study the abnormal expression of β-catenin gene and its relationship with invasiveness of primary hepatocellular carcinoma among Chinese people.METHODS Thirty-four hepatocellular carcinoma (HCC) specimens and adjacent para-cancerous tissues, 4 normal liver tissues were immunohistochemically stained to study subcellular distribution of β-catenin. Semiquantitive analysis of expression of β-catenin gene exon 3 mRNA was examined by RT-PCR and in situ hybridization. The relationship between expressions of both β-catenin protein, mRNA and clinicopathological characteristics of HCC was also analyzed.RESULTS Immunohistochemistry showed that all normal liver tissues and para-cancerous tissues examined displayed membranous type staining for β-catenin protein,occasionally with weak expression in the cytoplasm.While 21 cases (61.8%) of HCC examined showed accumulated type in cytoplasms or nuclei. The accumuled type Labling Index (LI) of cancer tissue and paracancarous tissue was (59.9 ± 26.3) and (18.3 ± 9.7)respectively (P＜0.01). Higher accumulated type LI was closely related with invasiveness of HCC. Results of RTPCR showed the β-catenin gene exon 3 mRNA Expression Index (El) of 34 HCCs was higher than that of paracancerous tissue and normal liver tissue. Using in situ hybridization, the signal corresponding to β-catenin gene exon 3 mRNA was particularly strong in cytoplasm of HCC when compared with those of para-cancerous and normal liver tissues. Over expression of β-catenin exon 3 was also found to be correlated with high metastatic potential of HCC.CONCLUSION Abnormal expression of β-catenin gene may contribute importantly to the invasiveness of HCC among Chinese people.
