The WW domain-containing oxidoreductase（WWOX） is a tumor suppressor in a variety of cancers, including breast cancer. Reduced WWOX expression is associated with the basal-like subtype and a relatively poor disease-f...The WW domain-containing oxidoreductase（WWOX） is a tumor suppressor in a variety of cancers, including breast cancer. Reduced WWOX expression is associated with the basal-like subtype and a relatively poor disease-free survival rate among breast cancer patients. Though several WWOX partners have been identified, the functional mechanisms of WWOX＇s role in cancers have not been fully addressed to date. In the current study, we found WWOX suppresses expression of KLF5—an oncogenic transcription factor—at protein level, and suppresses cancer cell proliferation in both bladder and breast cancer cell lines. Furthermore, we demonstrated that WWOX physically interacts with KLF5 via the former＇s WW domains and the latter＇s PY motifs. Interestingly, we found the expression of WWOX negatively correlates with KLF5 expression in a panel of breast cancer cell lines. Taken together, we conjecture that WWOX may suppress cancer cell proliferation partially by reducing the expression of KLF5.展开更多
Objective:To explore the role of circROBO1 in promoting the invasion of retinal Y79 cells by targeting KLF5 and its possible regulatory mechanism.Methods:RNase R enzyme digestion and qRT-PCR experiments were used to d...Objective:To explore the role of circROBO1 in promoting the invasion of retinal Y79 cells by targeting KLF5 and its possible regulatory mechanism.Methods:RNase R enzyme digestion and qRT-PCR experiments were used to detect the structural stability of circular circROBO1 in retinal Y79 cells;cytoplasmic and nuclear RNAs of retinal Y79 cells were extracted for localization analysis of circROBO1;The expression of circROBO1 in retinal Y79 cells were silenced by siRNA.The effect of circROBO1 on the migration and invasion ability of HT-29 cells was detected by scratch assay,Transwell cell invasion and migration assay.The target binding sites of circROBO1 and its downstream miRNA and that of miRNA and its downstream target gene KLF5 were predicted by CircInteractome and TargetScan online software respectively,and the target regulation relationship between them was verified by double luciferase reporter gene experiment.Western blot was used to detect the effect of siRNA silencing the expression of circROBO1 in Y79 cells on the expression of KLF5.Results:Compared with the control group without RNase R enzyme treatment,relative circROBO1 levels did not change significantly after treatment,while relative linear ROBO1 levels decreased significantly after treatment(t=16.18,P<0.05);the content of circROBO1 in the cytoplasm was significantly higher than that in the nucleus(P<0.05);compared with si-control group,the migration rate and the invasion and migration abilities of Transwell cells were all lower in the si-circROBO1 group(t=22.54,P<0.05);circROBO1 can adsorb miR-885-5p,and there is a target binding site between miR-885-5p and KLF5(t=11.39,P<0.05);compared with the si-control group,the KLF5 protein expression in the si-circROBO1 group was significantly decreased(t=17.26,P<0.05).Conclusions:circROBO1 promotes retinalY79 cell tumor invasion by targeting KLF5.展开更多
The effective proliferation and differentiation of trophoblast stem cells(TSCs)is indispensable for the development of the placenta,which is the key to maintaining normal fetal growth during pregnancy.Kruppel-like fac...The effective proliferation and differentiation of trophoblast stem cells(TSCs)is indispensable for the development of the placenta,which is the key to maintaining normal fetal growth during pregnancy.Kruppel-like factor 5(Klf5)is implicated in the activation of pluripotency gene expression in embryonic stem cells(ESCs),yet its function in TSCs is poorly understood.Here,we showed that Klf5 knockdown resulted in the downregulation of core TSC-specific genes,consequently causing rapid differentiation of TSCs.Consistently,Klf5-depleted embryos lost the ability to establish TSCs in vitro.At the molecular level,Klf5 preferentially occupied the proximal promoter regions and maintained an open chromatin architecture of key TSC-specific genes.Deprivation of Klf5 impaired the enrichment of p300,a major histone acetyl transferase of H3 lysine 27 acetylation(H3K27ac),and further reduced the occupancy of H3K27ac at promoter regions,leading to decreased transcriptional activity of TSC pluripotency genes.Thus,our findings highlight a novel mechanism of Klf5 in regulating the self-renewal and differentiation of TSCs and provide a reference for understanding placental development and improving pregnancy rates.展开更多
基金supported by National Natural Science Foundation of China (81272930, 81322038, 31260208, and U1132605)the Science and Technological Key Project of Yunnan Province (2012FB185)West Light Foundation of the Chinese Academy of Sciences (to R.L.)
文摘The WW domain-containing oxidoreductase（WWOX） is a tumor suppressor in a variety of cancers, including breast cancer. Reduced WWOX expression is associated with the basal-like subtype and a relatively poor disease-free survival rate among breast cancer patients. Though several WWOX partners have been identified, the functional mechanisms of WWOX＇s role in cancers have not been fully addressed to date. In the current study, we found WWOX suppresses expression of KLF5—an oncogenic transcription factor—at protein level, and suppresses cancer cell proliferation in both bladder and breast cancer cell lines. Furthermore, we demonstrated that WWOX physically interacts with KLF5 via the former＇s WW domains and the latter＇s PY motifs. Interestingly, we found the expression of WWOX negatively correlates with KLF5 expression in a panel of breast cancer cell lines. Taken together, we conjecture that WWOX may suppress cancer cell proliferation partially by reducing the expression of KLF5.
基金Key Project of Hunan Provincial Department of Education(No.21A0285)。
文摘Objective:To explore the role of circROBO1 in promoting the invasion of retinal Y79 cells by targeting KLF5 and its possible regulatory mechanism.Methods:RNase R enzyme digestion and qRT-PCR experiments were used to detect the structural stability of circular circROBO1 in retinal Y79 cells;cytoplasmic and nuclear RNAs of retinal Y79 cells were extracted for localization analysis of circROBO1;The expression of circROBO1 in retinal Y79 cells were silenced by siRNA.The effect of circROBO1 on the migration and invasion ability of HT-29 cells was detected by scratch assay,Transwell cell invasion and migration assay.The target binding sites of circROBO1 and its downstream miRNA and that of miRNA and its downstream target gene KLF5 were predicted by CircInteractome and TargetScan online software respectively,and the target regulation relationship between them was verified by double luciferase reporter gene experiment.Western blot was used to detect the effect of siRNA silencing the expression of circROBO1 in Y79 cells on the expression of KLF5.Results:Compared with the control group without RNase R enzyme treatment,relative circROBO1 levels did not change significantly after treatment,while relative linear ROBO1 levels decreased significantly after treatment(t=16.18,P<0.05);the content of circROBO1 in the cytoplasm was significantly higher than that in the nucleus(P<0.05);compared with si-control group,the migration rate and the invasion and migration abilities of Transwell cells were all lower in the si-circROBO1 group(t=22.54,P<0.05);circROBO1 can adsorb miR-885-5p,and there is a target binding site between miR-885-5p and KLF5(t=11.39,P<0.05);compared with the si-control group,the KLF5 protein expression in the si-circROBO1 group was significantly decreased(t=17.26,P<0.05).Conclusions:circROBO1 promotes retinalY79 cell tumor invasion by targeting KLF5.
基金This work was supported by the National Natural.Science Foundation of China(31970822 and 31902161)the Key Research and Development Program of Hubei Province(2021BBA221 and 2022BCE002)+1 种基金the Fundamental Research Funds for the Central Universities(2662022DKPY001)the Major Project of Hubei Hongshan Laboratory(2021hszdo03)。
文摘The effective proliferation and differentiation of trophoblast stem cells(TSCs)is indispensable for the development of the placenta,which is the key to maintaining normal fetal growth during pregnancy.Kruppel-like factor 5(Klf5)is implicated in the activation of pluripotency gene expression in embryonic stem cells(ESCs),yet its function in TSCs is poorly understood.Here,we showed that Klf5 knockdown resulted in the downregulation of core TSC-specific genes,consequently causing rapid differentiation of TSCs.Consistently,Klf5-depleted embryos lost the ability to establish TSCs in vitro.At the molecular level,Klf5 preferentially occupied the proximal promoter regions and maintained an open chromatin architecture of key TSC-specific genes.Deprivation of Klf5 impaired the enrichment of p300,a major histone acetyl transferase of H3 lysine 27 acetylation(H3K27ac),and further reduced the occupancy of H3K27ac at promoter regions,leading to decreased transcriptional activity of TSC pluripotency genes.Thus,our findings highlight a novel mechanism of Klf5 in regulating the self-renewal and differentiation of TSCs and provide a reference for understanding placental development and improving pregnancy rates.
