Objective Mycobacterium tuberculosis(Mtb),the causative agent of tuberculosis(TB),causes an estimated 1.6 million human deaths annually,but the pathogenesis of TB remains unclear.Immunity plays a critical role in the ...Objective Mycobacterium tuberculosis(Mtb),the causative agent of tuberculosis(TB),causes an estimated 1.6 million human deaths annually,but the pathogenesis of TB remains unclear.Immunity plays a critical role in the onset and outcome of TB.This study aimed to uncover the roles of innate and adaptive immunity in TB.Methods The gene expression profiles generated by RNA sequencing from human peripheral blood mononuclear cells(PBMCs)stimulated with or without Mtb strain H37Rv antigens were analyzed.A total of 973 differentially expressed mRNAs were identified.Results The differentially expressed genes were enriched in innate immunity signaling functions.The mesenchymal-epithelial transition factor(MET)gene was significantly upregulated in CD14^(+)monocytes.A MET inhibitor improved the uptake of the BCG strain by monocytes and macrophages as well as inhibited the expression of indoleamine 2,3-dioxygenase(IDO).The expression of IDO was increased in PBMCs stimulated with Mtb antigens,and the IDO inhibitor promoted the expression of CD40,CD83,and CD86.Conclusion Our results might provide clues regarding the immunomodulatory mechanisms used by Mtb to evade the host defense system.展开更多
Epithelial-mesenchymal transition（EMT） and mesenchymal-epithelial transition（MET） are essential for embryonic development and also important in cancer progression. In a conventional model, epithelial-like cancer c...Epithelial-mesenchymal transition（EMT） and mesenchymal-epithelial transition（MET） are essential for embryonic development and also important in cancer progression. In a conventional model, epithelial-like cancer cells transit to mesenchymal-like tumor cells with great motility via EMT transcription factors; these mesenchymallike cells migrate through the circulation system, relocate to a suitable site and then convert back to an epithelial-like phenotype to regenerate the tumor. However, recent findings challenge this conventional model and support the existence of a stable hybrid epithelial/mesenchymal（E/M） tumor population. Hybrid E/M tumor cells exhibit both epithelial and mesenchymal properties, possess great metastatic and tumorigenic capacity and are associated with poorer patient prognosis. The hybrid E/M model and associated regulatory networks represent a conceptual change regarding tumor metastasis and organ colonization. It may lead to the development of novel treatment strategies to ultimately stop cancer progression and improve disease-free survival.展开更多
The liver is the most common site of metastases in patients with colorectal cancer.Colorectal liver metastases(CRLMs)are the result of molecular mechanisms that involve different cells of the liver microenvironment.Th...The liver is the most common site of metastases in patients with colorectal cancer.Colorectal liver metastases(CRLMs)are the result of molecular mechanisms that involve different cells of the liver microenvironment.The aberrant activation of Wingless/It(Wnt)/β-catenin signals downstream of Wnt ligands initially drives the oncogenic transformation of the colon epithelium,but also the progression of metastatization through the epithelial-mesenchymal transition/mesenchymalepithelial transition interactions.In liver microenvironment,metastatic cells can also survive and adapt through dormancy,which makes them less susceptible to pro-apoptotic signals and therapies.Treatment of CRLMs is challenging due to its variability and heterogeneity.Advances in surgery and oncology have been made in the last decade and a pivotal role for Wnt/β-catenin pathway has been recognized in chemoresistance.At the state of art,there is a lack of clear understanding of why and how this occurs and thus where exactly the opportunities for developing anti-CRLMs therapies may lie.In this review,current knowledge on the involvement of Wnt signaling in the development of CRLMs was considered.In addition,an overview of useful biomarkers with a revision of surgical and non-surgical therapies currently accepted in the clinical practice for colorectal liver metastasis patients were provided.展开更多
Objective: To observe MET-associated alteration during the trans-differentiation from MSCs to neuron-like cells, and to explore the possible molecular mechanism. Methods: Bone marrow MSCs were isolated from rat femur ...Objective: To observe MET-associated alteration during the trans-differentiation from MSCs to neuron-like cells, and to explore the possible molecular mechanism. Methods: Bone marrow MSCs were isolated from rat femur and purified in continuous cell culture. After induced differentiation to neuron-like cells by the combination of butylated hydroxyanisole(BHA)and dimethyl sulfoxide(DMSO), cells were tested by comparative polymerase chain reaction(PCR) for the relative expression of MET biomarkers and transcription factors, and for cell cycle by flow cytometry. Meanwhile, target genes of Wnt/β-catenin pathway were also analyzed by comparative PCR to determine the possible involvement. Results: In MSC-induced neuron-like cells, MET-associated transcription factors such as Snail, Slug, ZEB1, ZEB2, and Twist were significantly attenuated in expression level. The Mesenchymal marker Vimentin expression level was increased. Membrane protein E-cad was slightly down-regulated, while N-cad level was marginally elevated. Percentage of proliferating cells(S phase in cell cycle) markedly shrank from 40.42% for MSCs to 6.76% for MSC-derived neuron. Additionally, Wnt/β-catenin target genes β-catenin and c-myc were decreasingly expressed. Conclusion: Chemically induced trans-differentiation from MSC to neuron caused similar MET-featured alteration in gene expression and proliferation to known MET, which might be underlied by deactivation of Wnt/ β-catenin pathway.展开更多
BACKGROUND Due to the rarity of mesenchymal-epithelial transition factor(MET)fusions,the clinical efficacy of crizotinib has only been described in a few patients with MET fusions involving various fusion partners.Her...BACKGROUND Due to the rarity of mesenchymal-epithelial transition factor(MET)fusions,the clinical efficacy of crizotinib has only been described in a few patients with MET fusions involving various fusion partners.Herein,we report the clinical response to crizotinib of a patient with advanced poorly differentiated non-small cell carcinoma(NSCLC)having concurrent MET fusions.CASE SUMMARY A 46-year-old woman was diagnosed with poorly differentiated NSCLC(T4 N3 M1).With no classic driver mutations,she was treated with two cycles of gemcitabine and cisplatin without clinical benefit.Targeted sequencing revealed the detection of two concurrent MET fusions,KIF5 B-MET and novel MET-CDR2.Crizotinib was initiated at a dose of 250 mg twice daily.Within 4 wk of crizotinib therapy,repeat computed chromatography revealed a dramatic reduction in primary and metastatic lesions,assessed as partial response.She continued to benefit from crizotinib for 3 mo until disease progression and died within 1 mo despite receiving nivolumab therapy.CONCLUSION Crizotinib sensitivity was observed in an advanced poorly differentiated NSCLC patient with concurrent MET fusions KIF5 B-MET and MET-CDR2.Crizotinib can serve as a therapeutic option for patients with MET fusions.In addition,our case also highlights the importance of comprehensive genomic profiling particularly in patients with no classic driver mutation for guiding alternative therapeutic decisions.展开更多
BACKGROUND:Mesenchymal stem cells(MSCs)and fibro-blasts have intimate relationships,and the phenotypic homology between fibroblasts and MSCs has been recently described.The aim of this study was to investigate the hep...BACKGROUND:Mesenchymal stem cells(MSCs)and fibro-blasts have intimate relationships,and the phenotypic homology between fibroblasts and MSCs has been recently described.The aim of this study was to investigate the hepatic differentiating potential of human fibroblasts in cirrhotic liver. METHODS:The phenotypes of fibroblasts in cirrhotic liver were labeled by biological methods.After that,the differentiation potential of these fibroblasts in vitro was characterized in terms of liver-specific gene and protein expression.Finally,an animal model of hepatocyte regeneration in severe combined immunodeficient(SCID)mice was created by retrorsine injection and partial hepatectomy,and the expression of human hepatocyte proteins in SCID mouse livers was checked by immunohistochemical analysis after fibroblast administration. RESULTS:Surface immunophenotyping revealed that a minority of fibroblasts expressed markers of MSCs and hepatic epithelial cytokeratins as well as alpha-smooth muscle actin, but homogeneously expressed vimentin,desmin,prolyl 4-hydroxylase and fibronectin.These fibroblasts presented the characteristics of hepatocytes in vitro and differentiated directly into functional hepatocytes in the liver of hepatecto-mized SCID mice.CONCLUSIONS:This study demonstrated that fibroblasts in cirrhotic liver have the potential to differentiate into hepatocyte-like cells in vitro and in vivo.Our findings infer that hepatic differentiation of fibroblasts may serve as a new target for reversion of liver fibrosis and a cell source for tissue engineering.展开更多
基金This study was supported by the Thirteen-Fifth Mega-Scientific Project on“Prevention and Treatment of AIDS,Viral Hepatitis and Other Infectious Diseases”(No.2017ZX10201301-007-002)the National Natural Science Foundation of China(No.81571961 and No.82072233)the 309th Hospital(No.2017ZD-007).
文摘Objective Mycobacterium tuberculosis(Mtb),the causative agent of tuberculosis(TB),causes an estimated 1.6 million human deaths annually,but the pathogenesis of TB remains unclear.Immunity plays a critical role in the onset and outcome of TB.This study aimed to uncover the roles of innate and adaptive immunity in TB.Methods The gene expression profiles generated by RNA sequencing from human peripheral blood mononuclear cells(PBMCs)stimulated with or without Mtb strain H37Rv antigens were analyzed.A total of 973 differentially expressed mRNAs were identified.Results The differentially expressed genes were enriched in innate immunity signaling functions.The mesenchymal-epithelial transition factor(MET)gene was significantly upregulated in CD14^(+)monocytes.A MET inhibitor improved the uptake of the BCG strain by monocytes and macrophages as well as inhibited the expression of indoleamine 2,3-dioxygenase(IDO).The expression of IDO was increased in PBMCs stimulated with Mtb antigens,and the IDO inhibitor promoted the expression of CD40,CD83,and CD86.Conclusion Our results might provide clues regarding the immunomodulatory mechanisms used by Mtb to evade the host defense system.
基金supported by operating grants from Canadian Breast Cancer Foundation-Ontario Regionthe Canadian Institutes of Health Research MOP111224 to LW
文摘Epithelial-mesenchymal transition（EMT） and mesenchymal-epithelial transition（MET） are essential for embryonic development and also important in cancer progression. In a conventional model, epithelial-like cancer cells transit to mesenchymal-like tumor cells with great motility via EMT transcription factors; these mesenchymallike cells migrate through the circulation system, relocate to a suitable site and then convert back to an epithelial-like phenotype to regenerate the tumor. However, recent findings challenge this conventional model and support the existence of a stable hybrid epithelial/mesenchymal（E/M） tumor population. Hybrid E/M tumor cells exhibit both epithelial and mesenchymal properties, possess great metastatic and tumorigenic capacity and are associated with poorer patient prognosis. The hybrid E/M model and associated regulatory networks represent a conceptual change regarding tumor metastasis and organ colonization. It may lead to the development of novel treatment strategies to ultimately stop cancer progression and improve disease-free survival.
文摘The liver is the most common site of metastases in patients with colorectal cancer.Colorectal liver metastases(CRLMs)are the result of molecular mechanisms that involve different cells of the liver microenvironment.The aberrant activation of Wingless/It(Wnt)/β-catenin signals downstream of Wnt ligands initially drives the oncogenic transformation of the colon epithelium,but also the progression of metastatization through the epithelial-mesenchymal transition/mesenchymalepithelial transition interactions.In liver microenvironment,metastatic cells can also survive and adapt through dormancy,which makes them less susceptible to pro-apoptotic signals and therapies.Treatment of CRLMs is challenging due to its variability and heterogeneity.Advances in surgery and oncology have been made in the last decade and a pivotal role for Wnt/β-catenin pathway has been recognized in chemoresistance.At the state of art,there is a lack of clear understanding of why and how this occurs and thus where exactly the opportunities for developing anti-CRLMs therapies may lie.In this review,current knowledge on the involvement of Wnt signaling in the development of CRLMs was considered.In addition,an overview of useful biomarkers with a revision of surgical and non-surgical therapies currently accepted in the clinical practice for colorectal liver metastasis patients were provided.
文摘Objective: To observe MET-associated alteration during the trans-differentiation from MSCs to neuron-like cells, and to explore the possible molecular mechanism. Methods: Bone marrow MSCs were isolated from rat femur and purified in continuous cell culture. After induced differentiation to neuron-like cells by the combination of butylated hydroxyanisole(BHA)and dimethyl sulfoxide(DMSO), cells were tested by comparative polymerase chain reaction(PCR) for the relative expression of MET biomarkers and transcription factors, and for cell cycle by flow cytometry. Meanwhile, target genes of Wnt/β-catenin pathway were also analyzed by comparative PCR to determine the possible involvement. Results: In MSC-induced neuron-like cells, MET-associated transcription factors such as Snail, Slug, ZEB1, ZEB2, and Twist were significantly attenuated in expression level. The Mesenchymal marker Vimentin expression level was increased. Membrane protein E-cad was slightly down-regulated, while N-cad level was marginally elevated. Percentage of proliferating cells(S phase in cell cycle) markedly shrank from 40.42% for MSCs to 6.76% for MSC-derived neuron. Additionally, Wnt/β-catenin target genes β-catenin and c-myc were decreasingly expressed. Conclusion: Chemically induced trans-differentiation from MSC to neuron caused similar MET-featured alteration in gene expression and proliferation to known MET, which might be underlied by deactivation of Wnt/ β-catenin pathway.
基金Supported by the National Key R&D Program of ChinaNo. 2017YFC0907900 and 2017YFC0907904
文摘BACKGROUND Due to the rarity of mesenchymal-epithelial transition factor(MET)fusions,the clinical efficacy of crizotinib has only been described in a few patients with MET fusions involving various fusion partners.Herein,we report the clinical response to crizotinib of a patient with advanced poorly differentiated non-small cell carcinoma(NSCLC)having concurrent MET fusions.CASE SUMMARY A 46-year-old woman was diagnosed with poorly differentiated NSCLC(T4 N3 M1).With no classic driver mutations,she was treated with two cycles of gemcitabine and cisplatin without clinical benefit.Targeted sequencing revealed the detection of two concurrent MET fusions,KIF5 B-MET and novel MET-CDR2.Crizotinib was initiated at a dose of 250 mg twice daily.Within 4 wk of crizotinib therapy,repeat computed chromatography revealed a dramatic reduction in primary and metastatic lesions,assessed as partial response.She continued to benefit from crizotinib for 3 mo until disease progression and died within 1 mo despite receiving nivolumab therapy.CONCLUSION Crizotinib sensitivity was observed in an advanced poorly differentiated NSCLC patient with concurrent MET fusions KIF5 B-MET and MET-CDR2.Crizotinib can serve as a therapeutic option for patients with MET fusions.In addition,our case also highlights the importance of comprehensive genomic profiling particularly in patients with no classic driver mutation for guiding alternative therapeutic decisions.
基金supported by grants from the National Basic Research Program of China(2009CB522403)the Program for Changjiang Scholars and Innovative Research Team in University(IRT0753)+1 种基金the National Natural Science Foundation of China(30801327)National Key Scientific and Technological Research program(2008ZX10002-022)
文摘BACKGROUND:Mesenchymal stem cells(MSCs)and fibro-blasts have intimate relationships,and the phenotypic homology between fibroblasts and MSCs has been recently described.The aim of this study was to investigate the hepatic differentiating potential of human fibroblasts in cirrhotic liver. METHODS:The phenotypes of fibroblasts in cirrhotic liver were labeled by biological methods.After that,the differentiation potential of these fibroblasts in vitro was characterized in terms of liver-specific gene and protein expression.Finally,an animal model of hepatocyte regeneration in severe combined immunodeficient(SCID)mice was created by retrorsine injection and partial hepatectomy,and the expression of human hepatocyte proteins in SCID mouse livers was checked by immunohistochemical analysis after fibroblast administration. RESULTS:Surface immunophenotyping revealed that a minority of fibroblasts expressed markers of MSCs and hepatic epithelial cytokeratins as well as alpha-smooth muscle actin, but homogeneously expressed vimentin,desmin,prolyl 4-hydroxylase and fibronectin.These fibroblasts presented the characteristics of hepatocytes in vitro and differentiated directly into functional hepatocytes in the liver of hepatecto-mized SCID mice.CONCLUSIONS:This study demonstrated that fibroblasts in cirrhotic liver have the potential to differentiate into hepatocyte-like cells in vitro and in vivo.Our findings infer that hepatic differentiation of fibroblasts may serve as a new target for reversion of liver fibrosis and a cell source for tissue engineering.
