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
Penicillium digitatum is the most important pathogen of postharvest citrus. Gene targeting can be done in P. digitatum using homologous recombination via Agrobacterium tumefaciens mediated transformation （ATMT）, but...Penicillium digitatum is the most important pathogen of postharvest citrus. Gene targeting can be done in P. digitatum using homologous recombination via Agrobacterium tumefaciens mediated transformation （ATMT）, but the frequencies are often very low. In the present study, we replaced the Ku80 homolog （a gene of the non-homologous end-joining （NHEJ） pathway） with the hygromycin resistance cassette （hph） by ATMT. No significant change in vegetative growth, conidiation, or pathogenicity was observed in KuSO-deficient strain （△dKuSO） of P. digitatum. However, using △pdKuSO as a targeting strain, the gene-targeting frequencies for both genes PdbrlA and PdmpkA were significantly increased. These results suggest that Ku80 plays an important role in homologous inte- gration and the created △PdKuSO strain would be a good candidate for rapid gene function analysis in P. digitatum.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supported by the National Natural Science Foundation of China(Nos.31371961 and 31071649)the China Agriculture Research System(No.CARS-27)the Special Fund for Agro-scientific Research in the Public Interest(No.201203034),China
文摘Penicillium digitatum is the most important pathogen of postharvest citrus. Gene targeting can be done in P. digitatum using homologous recombination via Agrobacterium tumefaciens mediated transformation （ATMT）, but the frequencies are often very low. In the present study, we replaced the Ku80 homolog （a gene of the non-homologous end-joining （NHEJ） pathway） with the hygromycin resistance cassette （hph） by ATMT. No significant change in vegetative growth, conidiation, or pathogenicity was observed in KuSO-deficient strain （△dKuSO） of P. digitatum. However, using △pdKuSO as a targeting strain, the gene-targeting frequencies for both genes PdbrlA and PdmpkA were significantly increased. These results suggest that Ku80 plays an important role in homologous inte- gration and the created △PdKuSO strain would be a good candidate for rapid gene function analysis in P. digitatum.
