Synthetic lethality is a novel model for cancer therapy.To understand the function and mechanism of BEN domain-containing protein 4(BEND4)in pancreatic cancer,eight cell lines and a total of 492 cases of pancreatic ne...Synthetic lethality is a novel model for cancer therapy.To understand the function and mechanism of BEN domain-containing protein 4(BEND4)in pancreatic cancer,eight cell lines and a total of 492 cases of pancreatic neoplasia samples were included in this study.Methylation-specific polymerase chain reaction,CRISPR/Cas9,immunoprecipitation assay,comet assay,and xenograft mouse model were used.BEND4 is a new member of the BEN domain family.The expression of BEND4 is regulated by promoter region methylation.It is methylated in 58.1%(176/303)of pancreatic ductal adenocarcinoma(PDAC),33.3%(14/42)of intraductal papillary mucinous neoplasm,31.0%(13/42)of pancreatic neuroendocrine tumor,14.3%(3/21)of mucinous cystic neoplasm,4.3%(2/47)of solid pseudopapillary neoplasm,and 2.7%(1/37)of serous cystic neoplasm.BEND4 methylation is significantly associated with late-onset PDAC(>50 years,P<0.01)and tumor differentiation(P<0.0001),and methylation of BEND4 is an independent poor prognostic marker(P<0.01)in PDAC.Furthermore,BEND4 plays tumor-suppressive roles in vitro and in vivo.Mechanistically,BEND4 involves non-homologous end joining signaling by interacting with Ku80 and promotes DNA damage repair.Loss of BEND4 increased the sensitivity of PDAC cells to ATM inhibitor.Collectively,the present study revealed an uncharacterized tumor suppressor BEND4 and indicated that methylation of BEND4 may serve as a potential synthetic lethal marker for ATM inhibitor in PDAC treatment.展开更多
Understanding the regulatory networks for germ cell fate specification is necessary to developing strategies for improving the efficiency of germ cell production in vitro.In this study,we developed a coupled screening...Understanding the regulatory networks for germ cell fate specification is necessary to developing strategies for improving the efficiency of germ cell production in vitro.In this study,we developed a coupled screening strategy that took advantage of an arrayed bi-molecular fluorescence complementation(BiFC)platform for protein-protein interaction screens and epiblast-like cell(EpiLC)-induction assays using reporter mouse embryonic stem cells(mESCs).Investigation of candidate interaction partners of core human pluripotent factors OCT4,NANOG,KLF4 and SOX2 in EpiLC differentiation assays identified novel primordial germ cell(PGC)-inducing factors including BEN-domain(BEND/Bend)family members.Through RNA-seq,ChIP-seq,and ATAC-seq analyses,we showed that Bend5 worked together with Bend4 and helped mark chromatin boundaries to promote EpiLC induction in vitro.Our findings suggest that BEND/Bend proteins represent a new family of transcriptional modulators and chromatin boundary factors that participate in gene expression regulation during early germline development.展开更多
基金supported by grants from the National Key Research and Development Program of China(Nos.2018YFA0208902 and 2020YFC2002705)the National Natural Science Foundation of China(Nos.82272632 and 81672138)Beijing Science Foundation of China(No.7171008)。
文摘Synthetic lethality is a novel model for cancer therapy.To understand the function and mechanism of BEN domain-containing protein 4(BEND4)in pancreatic cancer,eight cell lines and a total of 492 cases of pancreatic neoplasia samples were included in this study.Methylation-specific polymerase chain reaction,CRISPR/Cas9,immunoprecipitation assay,comet assay,and xenograft mouse model were used.BEND4 is a new member of the BEN domain family.The expression of BEND4 is regulated by promoter region methylation.It is methylated in 58.1%(176/303)of pancreatic ductal adenocarcinoma(PDAC),33.3%(14/42)of intraductal papillary mucinous neoplasm,31.0%(13/42)of pancreatic neuroendocrine tumor,14.3%(3/21)of mucinous cystic neoplasm,4.3%(2/47)of solid pseudopapillary neoplasm,and 2.7%(1/37)of serous cystic neoplasm.BEND4 methylation is significantly associated with late-onset PDAC(>50 years,P<0.01)and tumor differentiation(P<0.0001),and methylation of BEND4 is an independent poor prognostic marker(P<0.01)in PDAC.Furthermore,BEND4 plays tumor-suppressive roles in vitro and in vivo.Mechanistically,BEND4 involves non-homologous end joining signaling by interacting with Ku80 and promotes DNA damage repair.Loss of BEND4 increased the sensitivity of PDAC cells to ATM inhibitor.Collectively,the present study revealed an uncharacterized tumor suppressor BEND4 and indicated that methylation of BEND4 may serve as a potential synthetic lethal marker for ATM inhibitor in PDAC treatment.
基金the National Key R&D Program of China(2017YFA0102801)The National Natural Science Foundation of China(Grant Nos.31930058,31671540,32170802,and 31301082)+1 种基金Natural Science Foundation of Guangdong Province(2015B020228002,2017A030313093)Guangdong Basic and Applied Basic Research Foundation(2019A1515011422,2021A1515010759).
文摘Understanding the regulatory networks for germ cell fate specification is necessary to developing strategies for improving the efficiency of germ cell production in vitro.In this study,we developed a coupled screening strategy that took advantage of an arrayed bi-molecular fluorescence complementation(BiFC)platform for protein-protein interaction screens and epiblast-like cell(EpiLC)-induction assays using reporter mouse embryonic stem cells(mESCs).Investigation of candidate interaction partners of core human pluripotent factors OCT4,NANOG,KLF4 and SOX2 in EpiLC differentiation assays identified novel primordial germ cell(PGC)-inducing factors including BEN-domain(BEND/Bend)family members.Through RNA-seq,ChIP-seq,and ATAC-seq analyses,we showed that Bend5 worked together with Bend4 and helped mark chromatin boundaries to promote EpiLC induction in vitro.Our findings suggest that BEND/Bend proteins represent a new family of transcriptional modulators and chromatin boundary factors that participate in gene expression regulation during early germline development.