Ischemic accumulation of succinate causes cerebral damage by excess production of reactive oxygen species. However, it is unknown whether ischemic accumulation of succinate affects neural stem cell proliferation. In t...Ischemic accumulation of succinate causes cerebral damage by excess production of reactive oxygen species. However, it is unknown whether ischemic accumulation of succinate affects neural stem cell proliferation. In this study, we established a rat model of cerebral ischemia/reperfusion injury by occlusion of the middle cerebral artery. We found that succinate levels increased in serum and brain tissue(cortex and hippocampus) after ischemia/reperfusion injury. Oxygen-glucose deprivation and reoxygenation stimulated primary neural stem cells to produce abundant succinate. Succinate can be converted into diethyl succinate in cells. Exogenous diethyl succinate inhibited the proliferation of mouse-derived C17.2 neural stem cells and increased the infarct volume in the rat model of cerebral ischemia/reperfusion injury. Exogenous diethyl succinate also increased the succinylation of the Rho family GTPase Cdc42 but repressed Cdc42 GTPase activity in C17.2 cells. Increasing Cdc42 succinylation by knockdown of the desuccinylase Sirt5 also inhibited Cdc42 GTPase activity in C17.2 cells. Our findings suggest that ischemic accumulation of succinate decreases Cdc42 GTPase activity by induction of Cdc42 succinylation, which inhibits the proliferation of neural stem cells and aggravates cerebral ischemia/reperfusion injury.展开更多
AIM To determine whether cell division cycle(Cdc)42 is regulated by microRNA(miR)-15 a in the development of pediatric inflammatory bowel disease(IBD).METHODS We cultured 293 T cells, used plasmids and performed dual-...AIM To determine whether cell division cycle(Cdc)42 is regulated by microRNA(miR)-15 a in the development of pediatric inflammatory bowel disease(IBD).METHODS We cultured 293 T cells, used plasmids and performed dual-luciferase assay to determine whether Cdc42 is a miR-15 a target gene. We cultured Caco-2 cells, and stimulated them with tumor necrosis factor(TNF)-α. We then employed lentiviruses to alter the expression of miR-15 a and Cdc42. We performed quantitative reverse transcription polymerase chain reaction(qRTPCR) and immunofluorescence to determine whether Cdc42 is regulated by miR-15 a in Caco-2 cells. Finally, we collected ileocecal tissue by endoscopy from patients and performed qRT-PCR to examine the expression of miR-15 a and Cdc42 in pediatric IBD patients.RESULTS Target Scan and dual-luciferase assay revealed thatCdc42 was a miR-15 a target gene. MiR-15 a expression increased(P = 0.0038) and Cdc42 expression decreased(P = 0.0013) in cells stimulated with TNF-α, and the expression of the epithelial junction proteins zona occludens(ZO)-1(P < 0.05) and E-cadherin(P < 0.001) decreased. Cdc42 levels decreased in miR-15 a-mimic cells(P < 0.001) and increased in miR-15 a inhibitor cells(P < 0.05). ZO-1 and E-cadherin decreased in mi R-15 a-mimic cells(P < 0.001) but not in the miR-15 a inhibitor + TNF-α cells. In Lv-Cdc42 + TNF-α cells, ZO-1 and E-cadherin expression increased compared to the Lv-Cdc42-NC + TNF-α(P < 0.05) or miR-15 a-mimic cells(P < 0.05). Fifty-four pediatric IBD patients were included in this study, 21 in the control group, 19 in the Crohn's disease(CD) active(AC) group, seven in the CD remission(RE) group, and seven in the ulcerative colitis(UC) group. MiR-15 a increased and Cdc42 decreased in the CD AC group compared to the control group(P < 0.05). miR-15 a decreased and Cdc42 increased in the CD RE group compared to the CD AC group(P < 0.05). miR-15 a was positively correlated with the Pediatric Crohn's disease Activity Index(PCDAI)(P = 0.006), while Cdc42 was negatively correlated with PCDAI(P = 0.0008). Finally, miR-15 a expression negatively correlated with Cdc42 in pediatric IBD patients(P = 0.0045).CONCLUSION Mi R-15 a negatively regulates epithelial junctions through Cdc42 in Caco-2 cells and pediatric IBD patients.展开更多
Objective： The high expression of cell division cycle 42 protein （CDC42） may be involved in the occurrence and progression of several tumors. However, the expression and function of CDC42 in cervical squamous cell ...Objective： The high expression of cell division cycle 42 protein （CDC42） may be involved in the occurrence and progression of several tumors. However, the expression and function of CDC42 in cervical squamous cell carcinoma remains unclear. This study aimed to investigate the expression of CDC42 in cervical squamous cell carcinoma and its correlation with clinicopathologic characteristics. Methods： The expression of CDC42 in 162 cervical squamous cell carcinoma tissue samples and 33 normal cervical tissue samples was investigated by immunohistochemistry. The CDC42 mRNA expression was detected by reverse transcription-polymerase chain reaction （RT-PCR）. Results： The cervical squamous cell carcinoma group showed a significantly higher CDC42 positive rate, compared to the normal cervical tissues （P〈0.05）. Fttrthermore, the tissues of stage Ⅱ-Ⅳ carcinoma patients showed higher CDC42 expression levels compared to stage I patients （P=0.05）. In addition, the expression of CDC42 was not correlated to age of patients, differentiation degree of cancer cells, or lymph node metastasis （P〉0.05）. Furthermore, compare with normal cervical tissues, the CDC42 mRNA expression in cervical cancer had no significant difference. Conclusions： CDC42 was up-regulated at protein level, but not mRNA level, in cervical squamous cell carcinoma. The high expression of CDC42 was correlated to the clinical stage of the patients, indicating that CDC42 might contribute to the progression of cervical squamous cell carcinoma.展开更多
目的:分析和预测光滑念珠菌Cdc42基因及其编码蛋白的结构和特性。方法:利用NCBI、ExPASy和CBS网站中的各种信息分析工具,并结合Vector NTI suite 8.0生物信息学分析软件包,分析预测光滑念珠菌Cdc42基因并预测该基因编码蛋白结构的特征...目的:分析和预测光滑念珠菌Cdc42基因及其编码蛋白的结构和特性。方法:利用NCBI、ExPASy和CBS网站中的各种信息分析工具,并结合Vector NTI suite 8.0生物信息学分析软件包,分析预测光滑念珠菌Cdc42基因并预测该基因编码蛋白结构的特征和功能。结果:Cdc42基因全长为576 bp,编码区具有191个氨基酸,在GenBank同源序列中,其与酵母Cdc42氨基酸序列一致性达到99%,且有Cdc42保守域。Cdc42蛋白相对分子量预测为21 420.83,理论等电点为6.31。预测Cdc42编码蛋白ɑ螺旋(H)、β折叠(E)、无规则卷(L)的比例分别是29.84%、28.70%、41.88%,1个GTP/ATP结合位点。Cdc42蛋白为疏水蛋白,无跨膜区,无信号肽。结论:成功预测Cdc42基因及编码蛋白生化及结构特征,为下一步对其进行克隆和表达奠定基础。展开更多
To the Editor:Kinase cell division cycle 7(CDC7),a cell division cycle protein,takes a vital role in mediating DNA replication1.CDC7 complexes in the nucleus can phosphorylate the minichromosome maintenance complex(MC...To the Editor:Kinase cell division cycle 7(CDC7),a cell division cycle protein,takes a vital role in mediating DNA replication1.CDC7 complexes in the nucleus can phosphorylate the minichromosome maintenance complex(MCM)family members that bind to chromosomes.In addition,CDC7 kinase,as a molecular switch regulating DNA replication,can mediate DNA damage signaling pathways to stimulate cell cycle termination as well as DNA replication2.Studies have shown that CDC7 is overexpressed in many types of cancer cells,and its overexpression was related to poor patient survival,tumor grade,genetic instability,aneuploidy and so on3.Therefore,CDC7 is a promising target for antitumor therapy.展开更多
基金supported by the National Natural Science Foundation of China,No. 81671164 (to SHQ)the Natural Science Foundation of Jiangsu Province of China,No. BK20211348 (to SHQ)Xuzhou Basic Research Program,No. KC21030 (to LYH)。
文摘Ischemic accumulation of succinate causes cerebral damage by excess production of reactive oxygen species. However, it is unknown whether ischemic accumulation of succinate affects neural stem cell proliferation. In this study, we established a rat model of cerebral ischemia/reperfusion injury by occlusion of the middle cerebral artery. We found that succinate levels increased in serum and brain tissue(cortex and hippocampus) after ischemia/reperfusion injury. Oxygen-glucose deprivation and reoxygenation stimulated primary neural stem cells to produce abundant succinate. Succinate can be converted into diethyl succinate in cells. Exogenous diethyl succinate inhibited the proliferation of mouse-derived C17.2 neural stem cells and increased the infarct volume in the rat model of cerebral ischemia/reperfusion injury. Exogenous diethyl succinate also increased the succinylation of the Rho family GTPase Cdc42 but repressed Cdc42 GTPase activity in C17.2 cells. Increasing Cdc42 succinylation by knockdown of the desuccinylase Sirt5 also inhibited Cdc42 GTPase activity in C17.2 cells. Our findings suggest that ischemic accumulation of succinate decreases Cdc42 GTPase activity by induction of Cdc42 succinylation, which inhibits the proliferation of neural stem cells and aggravates cerebral ischemia/reperfusion injury.
基金Supported by the National Natural Science Foundation of Shanghai,No.201540068
文摘AIM To determine whether cell division cycle(Cdc)42 is regulated by microRNA(miR)-15 a in the development of pediatric inflammatory bowel disease(IBD).METHODS We cultured 293 T cells, used plasmids and performed dual-luciferase assay to determine whether Cdc42 is a miR-15 a target gene. We cultured Caco-2 cells, and stimulated them with tumor necrosis factor(TNF)-α. We then employed lentiviruses to alter the expression of miR-15 a and Cdc42. We performed quantitative reverse transcription polymerase chain reaction(qRTPCR) and immunofluorescence to determine whether Cdc42 is regulated by miR-15 a in Caco-2 cells. Finally, we collected ileocecal tissue by endoscopy from patients and performed qRT-PCR to examine the expression of miR-15 a and Cdc42 in pediatric IBD patients.RESULTS Target Scan and dual-luciferase assay revealed thatCdc42 was a miR-15 a target gene. MiR-15 a expression increased(P = 0.0038) and Cdc42 expression decreased(P = 0.0013) in cells stimulated with TNF-α, and the expression of the epithelial junction proteins zona occludens(ZO)-1(P < 0.05) and E-cadherin(P < 0.001) decreased. Cdc42 levels decreased in miR-15 a-mimic cells(P < 0.001) and increased in miR-15 a inhibitor cells(P < 0.05). ZO-1 and E-cadherin decreased in mi R-15 a-mimic cells(P < 0.001) but not in the miR-15 a inhibitor + TNF-α cells. In Lv-Cdc42 + TNF-α cells, ZO-1 and E-cadherin expression increased compared to the Lv-Cdc42-NC + TNF-α(P < 0.05) or miR-15 a-mimic cells(P < 0.05). Fifty-four pediatric IBD patients were included in this study, 21 in the control group, 19 in the Crohn's disease(CD) active(AC) group, seven in the CD remission(RE) group, and seven in the ulcerative colitis(UC) group. MiR-15 a increased and Cdc42 decreased in the CD AC group compared to the control group(P < 0.05). miR-15 a decreased and Cdc42 increased in the CD RE group compared to the CD AC group(P < 0.05). miR-15 a was positively correlated with the Pediatric Crohn's disease Activity Index(PCDAI)(P = 0.006), while Cdc42 was negatively correlated with PCDAI(P = 0.0008). Finally, miR-15 a expression negatively correlated with Cdc42 in pediatric IBD patients(P = 0.0045).CONCLUSION Mi R-15 a negatively regulates epithelial junctions through Cdc42 in Caco-2 cells and pediatric IBD patients.
基金supported by the National Natural Science Foundation of China(No.11072006,No.10772007 and No.81070078)National Basic Research Program of China(973 Program,2013CB933702)
文摘Objective： The high expression of cell division cycle 42 protein （CDC42） may be involved in the occurrence and progression of several tumors. However, the expression and function of CDC42 in cervical squamous cell carcinoma remains unclear. This study aimed to investigate the expression of CDC42 in cervical squamous cell carcinoma and its correlation with clinicopathologic characteristics. Methods： The expression of CDC42 in 162 cervical squamous cell carcinoma tissue samples and 33 normal cervical tissue samples was investigated by immunohistochemistry. The CDC42 mRNA expression was detected by reverse transcription-polymerase chain reaction （RT-PCR）. Results： The cervical squamous cell carcinoma group showed a significantly higher CDC42 positive rate, compared to the normal cervical tissues （P〈0.05）. Fttrthermore, the tissues of stage Ⅱ-Ⅳ carcinoma patients showed higher CDC42 expression levels compared to stage I patients （P=0.05）. In addition, the expression of CDC42 was not correlated to age of patients, differentiation degree of cancer cells, or lymph node metastasis （P〉0.05）. Furthermore, compare with normal cervical tissues, the CDC42 mRNA expression in cervical cancer had no significant difference. Conclusions： CDC42 was up-regulated at protein level, but not mRNA level, in cervical squamous cell carcinoma. The high expression of CDC42 was correlated to the clinical stage of the patients, indicating that CDC42 might contribute to the progression of cervical squamous cell carcinoma.
文摘目的:分析和预测光滑念珠菌Cdc42基因及其编码蛋白的结构和特性。方法:利用NCBI、ExPASy和CBS网站中的各种信息分析工具,并结合Vector NTI suite 8.0生物信息学分析软件包,分析预测光滑念珠菌Cdc42基因并预测该基因编码蛋白结构的特征和功能。结果:Cdc42基因全长为576 bp,编码区具有191个氨基酸,在GenBank同源序列中,其与酵母Cdc42氨基酸序列一致性达到99%,且有Cdc42保守域。Cdc42蛋白相对分子量预测为21 420.83,理论等电点为6.31。预测Cdc42编码蛋白ɑ螺旋(H)、β折叠(E)、无规则卷(L)的比例分别是29.84%、28.70%、41.88%,1个GTP/ATP结合位点。Cdc42蛋白为疏水蛋白,无跨膜区,无信号肽。结论:成功预测Cdc42基因及编码蛋白生化及结构特征,为下一步对其进行克隆和表达奠定基础。
基金Zenji Research Laboratories for financial aid to this work
文摘To the Editor:Kinase cell division cycle 7(CDC7),a cell division cycle protein,takes a vital role in mediating DNA replication1.CDC7 complexes in the nucleus can phosphorylate the minichromosome maintenance complex(MCM)family members that bind to chromosomes.In addition,CDC7 kinase,as a molecular switch regulating DNA replication,can mediate DNA damage signaling pathways to stimulate cell cycle termination as well as DNA replication2.Studies have shown that CDC7 is overexpressed in many types of cancer cells,and its overexpression was related to poor patient survival,tumor grade,genetic instability,aneuploidy and so on3.Therefore,CDC7 is a promising target for antitumor therapy.
