Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour met...Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour metastasis by repressing cell adhesion molecules,including epithelial (E)-cadherin. Reduced intracellular adhesion may allow tumour cells to disseminate and spread throughout the body. A number of transcription proteins of the Snail superfamily have been implicated in EMT. These proteins have been shown to be over-expressed in advanced gastrointestinal (GI) tumours including oesophageal adenocarcinomas,colorectal carcinomas,gastric and pancreatic cancers,with a concomitant reduction in the expression of E-cadherin. Regulators of EMT may provide novel clinical targets to detect GI cancers early,so that cancers previously associated with a poor prognosis such as pancreatic cancer can be diagnosed before they become inoperable. Furthermore,pharmacological therapies designed to inhibit these proteins will aim to prevent local and distant tumour invasion.展开更多
Breast cancer is the most common cancer in women,and approximately 90% of breast cancer deaths are caused by local invasion and distant metastasis of tumor cells.Epithelial-mesenchymal transition(EMT) is a vital proce...Breast cancer is the most common cancer in women,and approximately 90% of breast cancer deaths are caused by local invasion and distant metastasis of tumor cells.Epithelial-mesenchymal transition(EMT) is a vital process for large-scale cell movement during morphogenesis at the time of embryonic development.Tumor cells usurp this developmental program to execute the multi-step process of tumorigenesis and metastasis.Several transcription factors and signals are involved in these events.In this review,we summarize recent advances in breast cancer researches that have provided new insights in the molecular mechanisms underlying EMT regulation during breast cancer progression and metastasis.We especially focus on the molecular pathways that control EMT.展开更多
Diabetic nephropathy （DN） is one of the most common microvascular complications in diabetes mellitus patients and is characterized by thickened glomeruIar basement membrane, increased extracellular matrix formation,...Diabetic nephropathy （DN） is one of the most common microvascular complications in diabetes mellitus patients and is characterized by thickened glomeruIar basement membrane, increased extracellular matrix formation, and podocyte loss. These phenomena lead to proteinuria and altered glomerular filtration rate, that is, the rate initially increases but progressively decreases. DN has become the leading cause of end-stage renal disease. Its prevalence shows a rapid growth trend and causes heavy social and economic burden in many countries. However, this disease is multifactorial, and its mechanism is poorly understood due to the complex pathogenesis of DN. In this review, we highlight the new molecular insights about the pathogenesis of DN from the aspects of immune inflammation response, epithelial-mesenchymal transition, apoptosis and mitochondrial damage, epigenetics, and podocyte-endothelial communication. This work offers groundwork for understanding the initiation and progression of DN, as well as provides ideas for developing new prevention and treatment measures.展开更多
Gastric cancer is one of the most common malignant tumors worldwide.Due to its intricate initiation and progression mechanisms,early detection and effective treatment of gastric cancer are difficult to achieve.The epi...Gastric cancer is one of the most common malignant tumors worldwide.Due to its intricate initiation and progression mechanisms,early detection and effective treatment of gastric cancer are difficult to achieve.The epithelial-mesenchymal transition(EMT)is characterized as a fundamental process that is critical for embryonic development,wound healing and fibrotic disease.Recent evidence has established that aberrant EMT activation in the human stomach is closely associated with gastric carcinogenesis and tumor progression.EMT activation endows gastric epithelial cells with increased characteristics of mesenchymal cells and reduces their epithelial features.Moreover,mesenchymal cells tend to dedifferentiate and acquire stem cell or tumorigenic phenotypes such as invasion,metastasis and apoptosis resistance as well as drug resistance during EMT progression.There are a number of molecules that indicate the stage of EMT(e.g.,E-cadherin,an epithelial cell biomarker);therefore,certain transcriptional proteins,especially E-cadherin transcriptional repressors,may participate in the regulation of EMT.In addition,EMT regulation may be associated with certain epigenetic mechanisms.The aforementioned molecules can be used as early diagnostic markers for gastric cancer,and EMT regulation can provide potential targets for gastric cancer therapy.Here,we review the role of these aspects of EMT in gastric cancer initiation and development.展开更多
Hepatocellular carcinoma(HCC) is the most common primary malignancy of the liver. It is the second leading cause of cancer-related deaths worldwide, with a very poor prognosis. In the United States, there has been onl...Hepatocellular carcinoma(HCC) is the most common primary malignancy of the liver. It is the second leading cause of cancer-related deaths worldwide, with a very poor prognosis. In the United States, there has been only minimal improvement in the prognosis for HCC patients over the past 15 years. Details of the molecular mechanisms and other mechanisms of HCC progression remain unclear. Consequently, there is an urgent need for better understanding of these mechanisms. HCC is often diagnosed at advanced stages, and most patients will therefore need systemic therapy, with sorafenib being the most common at the present time. However, sorafenib therapy only minimally enhances patient survival. This review provides a summary of some of the known mechanisms that either cause HCC or contribute to its progression. Included in this review are the roles of viral hepatitis, non-viral hepatitis, chronic alcohol intake, genetic predisposition and congenital abnormalities, toxic exposures, and autoimmune diseases of the liver. Well-established molecular mechanisms of HCC progression such as epithelial-mesenchymal transition, tumor-stromal interactions and the tumor microenvironment, cancer stem cells, and senescence bypass are also discussed. Additionally, we discuss the roles of circulating tumor cells,immunomodulation, and neural regulation as potential new mechanisms of HCC progression. A better understanding of these mechanisms could have implications for the development of novel and more effective therapeutic and prognostic strategies, which are critically needed.展开更多
AIM: To characterise expression of known E-cadherin repressors; Snail, Slug and Twist in the development of esophageal adenocarcinoma. METHODS: E-cadherin, Slug, Snail and Twist mRNA expression in Barrett's metapl...AIM: To characterise expression of known E-cadherin repressors; Snail, Slug and Twist in the development of esophageal adenocarcinoma. METHODS: E-cadherin, Slug, Snail and Twist mRNA expression in Barrett's metaplasia and esophageal adenocarcinoma specimens was examined by real-time reverse transcription-polymerase chain reaction (RT-PCR). Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels. The effect of Slug on epithelial mesenchymal transition (EMT) markers was examined by transfection of Slug into an adenocarcinoma line OE33.RESULTS: Cellular localisation of Slug in Barrett's metaplasia was largely cytoplasmic whilst in adenocarcinoma it was nuclear. Semi-quantitative analysis indicated that Slug was more abundant in adenocarcinoma compared to matched Barrett's metaplastic specimens. Snail and Twist were expressed in adenocarcinoma but were cytoplasmic in location and not induced compared to Barrett's mucosa. These observations were supported by mRNA studies where only Slug mRNA was shown to be over-expressed in adenocarcinoma and inversely correlated to E-cadherin expression. Overexpression of Slug in OE33 mediated E-cadherin repression and induced the mesenchymal markers vimentin and fibronectin.CONCLUSION: Progression to adenocarcinoma is associated with increased Slug expression and this may represent a mechanism of E-cadherin silencing.展开更多
microRNAs （miRNAs） are a class of non-coding RNAs that function as endogenous triggers of the RNA interference pathway. Studies have shown that thousands of human protein-coding genes are regulated by miRNAs, indica...microRNAs （miRNAs） are a class of non-coding RNAs that function as endogenous triggers of the RNA interference pathway. Studies have shown that thousands of human protein-coding genes are regulated by miRNAs, indicating that miRNAs are master regulators of many important biological processes, such as cancer development, miRNAs frequently have deregulated expression in many types of human cancers, and play critical roles in tumorigenesis, which functions either as tumor suppressors or as oncogenes. Recent studies have shown that miRNAs are highly related with cancer progression, including initiating, growth, apoptosis, invasion, and metastasis. Furthermore, miRNAs are shown to be responsible for the cancer-related inflam- mation, anti-cancer drug resistance, and regulation of cancer stem ceils. Therefore, miRNAs have generated great interest as a novel strategy in cancer diagnosis and therapy. Here we review the versatile roles of miRNAs in cancers and their potential applications for diagnosis, prognosis, and treatment as biomarkers.展开更多
文摘Epithelial-mesenchymal transition (EMT) is a highly conserved process that has been well characterised in embryogenesis. Studies have shown that the aberrant activation of EMT in adult epithelia can promote tumour metastasis by repressing cell adhesion molecules,including epithelial (E)-cadherin. Reduced intracellular adhesion may allow tumour cells to disseminate and spread throughout the body. A number of transcription proteins of the Snail superfamily have been implicated in EMT. These proteins have been shown to be over-expressed in advanced gastrointestinal (GI) tumours including oesophageal adenocarcinomas,colorectal carcinomas,gastric and pancreatic cancers,with a concomitant reduction in the expression of E-cadherin. Regulators of EMT may provide novel clinical targets to detect GI cancers early,so that cancers previously associated with a poor prognosis such as pancreatic cancer can be diagnosed before they become inoperable. Furthermore,pharmacological therapies designed to inhibit these proteins will aim to prevent local and distant tumour invasion.
基金supported by the grants from NIH (RO1CA125454)the Susan G. Komen Foundation (KG081310)the Mary Kay Ash Foundation (to B.P. Zhou)
文摘Breast cancer is the most common cancer in women,and approximately 90% of breast cancer deaths are caused by local invasion and distant metastasis of tumor cells.Epithelial-mesenchymal transition(EMT) is a vital process for large-scale cell movement during morphogenesis at the time of embryonic development.Tumor cells usurp this developmental program to execute the multi-step process of tumorigenesis and metastasis.Several transcription factors and signals are involved in these events.In this review,we summarize recent advances in breast cancer researches that have provided new insights in the molecular mechanisms underlying EMT regulation during breast cancer progression and metastasis.We especially focus on the molecular pathways that control EMT.
文摘Diabetic nephropathy （DN） is one of the most common microvascular complications in diabetes mellitus patients and is characterized by thickened glomeruIar basement membrane, increased extracellular matrix formation, and podocyte loss. These phenomena lead to proteinuria and altered glomerular filtration rate, that is, the rate initially increases but progressively decreases. DN has become the leading cause of end-stage renal disease. Its prevalence shows a rapid growth trend and causes heavy social and economic burden in many countries. However, this disease is multifactorial, and its mechanism is poorly understood due to the complex pathogenesis of DN. In this review, we highlight the new molecular insights about the pathogenesis of DN from the aspects of immune inflammation response, epithelial-mesenchymal transition, apoptosis and mitochondrial damage, epigenetics, and podocyte-endothelial communication. This work offers groundwork for understanding the initiation and progression of DN, as well as provides ideas for developing new prevention and treatment measures.
基金Supported by National Natural Science Foundation of China,No.81172186
文摘Gastric cancer is one of the most common malignant tumors worldwide.Due to its intricate initiation and progression mechanisms,early detection and effective treatment of gastric cancer are difficult to achieve.The epithelial-mesenchymal transition(EMT)is characterized as a fundamental process that is critical for embryonic development,wound healing and fibrotic disease.Recent evidence has established that aberrant EMT activation in the human stomach is closely associated with gastric carcinogenesis and tumor progression.EMT activation endows gastric epithelial cells with increased characteristics of mesenchymal cells and reduces their epithelial features.Moreover,mesenchymal cells tend to dedifferentiate and acquire stem cell or tumorigenic phenotypes such as invasion,metastasis and apoptosis resistance as well as drug resistance during EMT progression.There are a number of molecules that indicate the stage of EMT(e.g.,E-cadherin,an epithelial cell biomarker);therefore,certain transcriptional proteins,especially E-cadherin transcriptional repressors,may participate in the regulation of EMT.In addition,EMT regulation may be associated with certain epigenetic mechanisms.The aforementioned molecules can be used as early diagnostic markers for gastric cancer,and EMT regulation can provide potential targets for gastric cancer therapy.Here,we review the role of these aspects of EMT in gastric cancer initiation and development.
文摘Hepatocellular carcinoma(HCC) is the most common primary malignancy of the liver. It is the second leading cause of cancer-related deaths worldwide, with a very poor prognosis. In the United States, there has been only minimal improvement in the prognosis for HCC patients over the past 15 years. Details of the molecular mechanisms and other mechanisms of HCC progression remain unclear. Consequently, there is an urgent need for better understanding of these mechanisms. HCC is often diagnosed at advanced stages, and most patients will therefore need systemic therapy, with sorafenib being the most common at the present time. However, sorafenib therapy only minimally enhances patient survival. This review provides a summary of some of the known mechanisms that either cause HCC or contribute to its progression. Included in this review are the roles of viral hepatitis, non-viral hepatitis, chronic alcohol intake, genetic predisposition and congenital abnormalities, toxic exposures, and autoimmune diseases of the liver. Well-established molecular mechanisms of HCC progression such as epithelial-mesenchymal transition, tumor-stromal interactions and the tumor microenvironment, cancer stem cells, and senescence bypass are also discussed. Additionally, we discuss the roles of circulating tumor cells,immunomodulation, and neural regulation as potential new mechanisms of HCC progression. A better understanding of these mechanisms could have implications for the development of novel and more effective therapeutic and prognostic strategies, which are critically needed.
基金Supported by City Hospital Trust Fundthe University of Birmingham Scientific Project Grant
文摘AIM: To characterise expression of known E-cadherin repressors; Snail, Slug and Twist in the development of esophageal adenocarcinoma. METHODS: E-cadherin, Slug, Snail and Twist mRNA expression in Barrett's metaplasia and esophageal adenocarcinoma specimens was examined by real-time reverse transcription-polymerase chain reaction (RT-PCR). Semi-quantitative immunohistochemistry was used to examine cellular localisation and protein levels. The effect of Slug on epithelial mesenchymal transition (EMT) markers was examined by transfection of Slug into an adenocarcinoma line OE33.RESULTS: Cellular localisation of Slug in Barrett's metaplasia was largely cytoplasmic whilst in adenocarcinoma it was nuclear. Semi-quantitative analysis indicated that Slug was more abundant in adenocarcinoma compared to matched Barrett's metaplastic specimens. Snail and Twist were expressed in adenocarcinoma but were cytoplasmic in location and not induced compared to Barrett's mucosa. These observations were supported by mRNA studies where only Slug mRNA was shown to be over-expressed in adenocarcinoma and inversely correlated to E-cadherin expression. Overexpression of Slug in OE33 mediated E-cadherin repression and induced the mesenchymal markers vimentin and fibronectin.CONCLUSION: Progression to adenocarcinoma is associated with increased Slug expression and this may represent a mechanism of E-cadherin silencing.
基金supported by National Natural Science Foundation of China grants (No. 30872889, 81072215, 81001210, 81172580)Scientific Research Foundation for the Returned Overseas Chinese Scholars, State Education Ministry (No. 20098-8-2)+1 种基金State Key Laboratory of Oral Diseases Open Funding (SKLODOF2010-05)the Fundamental Research Funds of the Central Universities of China (2011)
文摘microRNAs （miRNAs） are a class of non-coding RNAs that function as endogenous triggers of the RNA interference pathway. Studies have shown that thousands of human protein-coding genes are regulated by miRNAs, indicating that miRNAs are master regulators of many important biological processes, such as cancer development, miRNAs frequently have deregulated expression in many types of human cancers, and play critical roles in tumorigenesis, which functions either as tumor suppressors or as oncogenes. Recent studies have shown that miRNAs are highly related with cancer progression, including initiating, growth, apoptosis, invasion, and metastasis. Furthermore, miRNAs are shown to be responsible for the cancer-related inflam- mation, anti-cancer drug resistance, and regulation of cancer stem ceils. Therefore, miRNAs have generated great interest as a novel strategy in cancer diagnosis and therapy. Here we review the versatile roles of miRNAs in cancers and their potential applications for diagnosis, prognosis, and treatment as biomarkers.
