Background:The rapid turnover of the intestinal epithelium is driven by the proliferation and differentiation of intestinal stem cells(ISCs).The dynamics of the F-actin cytoskeleton are critical for maintaining interc...Background:The rapid turnover of the intestinal epithelium is driven by the proliferation and differentiation of intestinal stem cells(ISCs).The dynamics of the F-actin cytoskeleton are critical for maintaining intercellular force and the signal transduction network.However,it remains unclear how direct interference with actin polymerization impacts ISC homeostasis.This study aims to reveal the regulatory effects of the F-actin cytoskeleton on the homeostasis of intestinal epithelium,as well as the potential risks of benproperine(BPP)as an anti-tumor drug.Methods:Phalloidin fluorescence staining was utilized to test F-actin polymerization.Flow cytom-etry and IHC staining were employed to discriminate different types of intestinal epithelial cells.Cell proliferation was assessed through bromo-deoxyuridine(BrdU)and 5-ethynyl-2-deoxyuridine(EdU)incorporation assays.The proliferation and differentiation of intestinal stem cells were replicated in vitro through organoid culture.Epithelial migrationwas evaluated through BrdU pulse labeling and chasing in mice.Results:The F-actin content was observed to significantly increase as crypt cells migrated into the villus region.Additionally,actin polymerization in secretory cells,especially in Paneth cells(PCs),was much higher than that in neighboring ISCs.Treatment with the newly identified actin-related protein 2/3 complex subunit 2(ARPC2)inhibitor BPP led to a dose-dependent increase or inhibition of intestinal organoid growth in vitro and crypt cell proliferation in vivo.Compared with the vehicle group,BPP treatment decreased the expression of Lgr5 ISC feature genes in vivo and in organoid culture.Meanwhile,PC differentiation derived from ISCs and progenitors was decreased by inhibition of F-actin polymerization.Mechanistically,BPP-induced actin polymerization inhibition may activate the Yes1-associated transcriptional regulator pathway,which affects ISC proliferation and differentiation.Accordingly,BPP treatment affected intestinal epithelial cell migration in a dose-dependent manner.Conclusion:Our findings indicate that the regulation of cytoskeleton reorganization can affect ISC homeostasis.In addition,inhibiting ARPC2 with the Food and Drug Administration-approved drug BPP represents a novel approach to influencing the turnover of intestinal epithelial cells.展开更多
Background:Clear cell renal cell carcinoma(ccRCC)is an aggressive malignancy associated with limited treatment options and poor prognosis.Emerging studies suggest that the actin-regulating protein actin-related protei...Background:Clear cell renal cell carcinoma(ccRCC)is an aggressive malignancy associated with limited treatment options and poor prognosis.Emerging studies suggest that the actin-regulating protein actin-related protein 2/3 complex subunit 1B(ARPC1B),a key regulatory protein within the actin cytoskeleton,could play a pivotal role in ccRCC progression.The current study aimed to uncover the biological functions of ARPC1B and the molecular mechanisms driving its effects in ccRCC.Methods:ARPC1B expression and prognostic implications were analyzed using data sourced from the Gene Expression Profiling Interactive Analysis(GEPIA)platform,immunohistochemical(IHC)staining on 150 tumor samples along with 30 corresponding normal tissues,and Western blotting(WB)analyses across multiple ccRCC-derived cell lines.Functional assays assessing cell proliferation,colony formation capability,migration,invasion,and in vivo tumorigenicity were conducted following either ARPC1B suppression or upregulation.Additionally,WB analysis was utilized to evaluate proteins linked to epithelial-to-mesenchymal transition(EMT)and the Wnt/β-catenin pathway.Results:The findings revealed a substantial elevation of ARPC1B in ccRCC tissues and cell lines,significantly associated with advanced TNM stages,higher Fuhrman grades,and reduced overall survival(OS)(p<0.001).Multivariate statistical analysis identified ARPC1B as a standalone prognostic factor.Silencing ARPC1B notably impaired ccRCC cellular activities,and tumorigenesis in animalmodels,whereas augmented ARPC1B expression enhanced these malignant phenotypes.Mechanistically,downregulation of ARPC1B suppressed Wnt/β-catenin signaling and disrupted EMT,indicated by reducedβ-catenin,c-Myc,cyclin D1,and ZEB-1 levels,and concurrently increased E-cadherin expression.Additionally,reactivation of theWnt/β-catenin pathway partly reversed the inhibitory effects of ARPC1B depletion on tumor growth and invasiveness.Conclusions:ARPC1B emerges as an essential oncogenic factor in ccRCC by stimulating EMT and activating the Wnt/β-catenin pathway,ultimately enhancing tumor aggressiveness and metastatic potential.Thus,targeting ARPC1B represents a promising therapeutic strategy,warranting further exploration in ccRCC management.展开更多
基金supported by the National Natural Science Foundation of China(81872556)Chongqing Academician Program(Basic Research and Frontier Exploration)cstc2018jcyj-yszxX0004.
文摘Background:The rapid turnover of the intestinal epithelium is driven by the proliferation and differentiation of intestinal stem cells(ISCs).The dynamics of the F-actin cytoskeleton are critical for maintaining intercellular force and the signal transduction network.However,it remains unclear how direct interference with actin polymerization impacts ISC homeostasis.This study aims to reveal the regulatory effects of the F-actin cytoskeleton on the homeostasis of intestinal epithelium,as well as the potential risks of benproperine(BPP)as an anti-tumor drug.Methods:Phalloidin fluorescence staining was utilized to test F-actin polymerization.Flow cytom-etry and IHC staining were employed to discriminate different types of intestinal epithelial cells.Cell proliferation was assessed through bromo-deoxyuridine(BrdU)and 5-ethynyl-2-deoxyuridine(EdU)incorporation assays.The proliferation and differentiation of intestinal stem cells were replicated in vitro through organoid culture.Epithelial migrationwas evaluated through BrdU pulse labeling and chasing in mice.Results:The F-actin content was observed to significantly increase as crypt cells migrated into the villus region.Additionally,actin polymerization in secretory cells,especially in Paneth cells(PCs),was much higher than that in neighboring ISCs.Treatment with the newly identified actin-related protein 2/3 complex subunit 2(ARPC2)inhibitor BPP led to a dose-dependent increase or inhibition of intestinal organoid growth in vitro and crypt cell proliferation in vivo.Compared with the vehicle group,BPP treatment decreased the expression of Lgr5 ISC feature genes in vivo and in organoid culture.Meanwhile,PC differentiation derived from ISCs and progenitors was decreased by inhibition of F-actin polymerization.Mechanistically,BPP-induced actin polymerization inhibition may activate the Yes1-associated transcriptional regulator pathway,which affects ISC proliferation and differentiation.Accordingly,BPP treatment affected intestinal epithelial cell migration in a dose-dependent manner.Conclusion:Our findings indicate that the regulation of cytoskeleton reorganization can affect ISC homeostasis.In addition,inhibiting ARPC2 with the Food and Drug Administration-approved drug BPP represents a novel approach to influencing the turnover of intestinal epithelial cells.
文摘Background:Clear cell renal cell carcinoma(ccRCC)is an aggressive malignancy associated with limited treatment options and poor prognosis.Emerging studies suggest that the actin-regulating protein actin-related protein 2/3 complex subunit 1B(ARPC1B),a key regulatory protein within the actin cytoskeleton,could play a pivotal role in ccRCC progression.The current study aimed to uncover the biological functions of ARPC1B and the molecular mechanisms driving its effects in ccRCC.Methods:ARPC1B expression and prognostic implications were analyzed using data sourced from the Gene Expression Profiling Interactive Analysis(GEPIA)platform,immunohistochemical(IHC)staining on 150 tumor samples along with 30 corresponding normal tissues,and Western blotting(WB)analyses across multiple ccRCC-derived cell lines.Functional assays assessing cell proliferation,colony formation capability,migration,invasion,and in vivo tumorigenicity were conducted following either ARPC1B suppression or upregulation.Additionally,WB analysis was utilized to evaluate proteins linked to epithelial-to-mesenchymal transition(EMT)and the Wnt/β-catenin pathway.Results:The findings revealed a substantial elevation of ARPC1B in ccRCC tissues and cell lines,significantly associated with advanced TNM stages,higher Fuhrman grades,and reduced overall survival(OS)(p<0.001).Multivariate statistical analysis identified ARPC1B as a standalone prognostic factor.Silencing ARPC1B notably impaired ccRCC cellular activities,and tumorigenesis in animalmodels,whereas augmented ARPC1B expression enhanced these malignant phenotypes.Mechanistically,downregulation of ARPC1B suppressed Wnt/β-catenin signaling and disrupted EMT,indicated by reducedβ-catenin,c-Myc,cyclin D1,and ZEB-1 levels,and concurrently increased E-cadherin expression.Additionally,reactivation of theWnt/β-catenin pathway partly reversed the inhibitory effects of ARPC1B depletion on tumor growth and invasiveness.Conclusions:ARPC1B emerges as an essential oncogenic factor in ccRCC by stimulating EMT and activating the Wnt/β-catenin pathway,ultimately enhancing tumor aggressiveness and metastatic potential.Thus,targeting ARPC1B represents a promising therapeutic strategy,warranting further exploration in ccRCC management.
