To explore the existence and distribution of nucleophosmin in the nuclear matrix and its co-localization with the other related gene products following HMBA treatment in the human hepatocarcinoma SMMC-7721 cells,the n...To explore the existence and distribution of nucleophosmin in the nuclear matrix and its co-localization with the other related gene products following HMBA treatment in the human hepatocarcinoma SMMC-7721 cells,the nuclear matrix of SMMC-7721 cells was extracted pre/post HMBA induced differentiation.2D PAGE proteomics analyses showed that nucleophosmin existed in the fractions of nuclear matrix proteins and was down-regulated after HMBA treatment with further confirmation by Western blot analysis.The immunofluorescence observation revealed that nucleophosmin located in the nuclear matrix,HMBA treatment altered its expression level and distribution profile.The co-localization of nucleophosmin with cancer-related genes and the products of oncogenes or tumor repression genes,including c-fos,c-myc,p53 and Rb,using laser scanning confocal microscopy,were evaluated,and substantial differences were observed following HMBA treatment.The results implies that nucleophosmin,as a nuclear matrix protein,the level of its expression and the colocalization with cancer-related gene products may play an important role during the differentiation of SMMC-7721 cell.展开更多
The behavior of UBF (upstream binding factor) and nucleophosmin in HeLa and HeLa-Bcl-2 cells during apoptosis induced by TNF-α, emetine, and their mixture was investigated. A pronounced apoptosis was achieved only in...The behavior of UBF (upstream binding factor) and nucleophosmin in HeLa and HeLa-Bcl-2 cells during apoptosis induced by TNF-α, emetine, and their mixture was investigated. A pronounced apoptosis was achieved only in HeLa cells treated with a mixture of the inducers. Immunoblotting analysis of UBF and nucleophosmin in samples containing different portions of cells with apoptotic nuclei was carried out. It showed that UBF was proteolytically cleaved giving a stable 76-kDa fragment. Increasing content of the fragment during apoptosis correlated with the level of cells containing apoptotic nuclei and with a decrease in the content of full-sized UBF. Determination of N- and C-terminal sequences of UBF and 76-kDa fragment allowed us not only to characterize UBF at the protein level, but also to describe the site of the apoptosis-specific proteolysis. Nucleophosmin did not undergo proteolytic cleavage during apoptosis and its content was unchanged even in a sample containing 100% of cells with apoptotic nuclei. However in cells reached terminal stages of apoptosis, the balance between mono- and oligomeric forms of nucleophosmin changed due to depletion of monomeric forms and appearance of two additional oligomeric forms with lower molecular weight.展开更多
Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation, apoptosis, ribosome assembly, and centrosome duplication; however, the role of NPM in cell cycle regulati...Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation, apoptosis, ribosome assembly, and centrosome duplication; however, the role of NPM in cell cycle regulation is not well characterized. We investigated the mechanism by which NPM is involved in cell cycle regulation. NPM was knocked down using siRNA in HepG2 hepatoblastoma cells. NPM translocation following actinomycin D (ActD) treatment was investigated using immunofluorescent staining. Expression of NPM and other factors involved in cell cycle regulation was examined by Western blotting. Cell cycle distribution was measured using flow cytometry to detect 5-ethynyl-2′-deoxyuridine (EdU) incorporation. Cell proliferation was quantified by the MTT assay. Knockdown of NPM increased the percentage of HepG2 cells in S phase and led to decreased expression of P53 and P21Cip1/WAF1. S-phase arrest in HepG2 cells was significantly enhanced by ActD treatment. Furthermore, knockdown of NPM abrogated ActD-induced G2/M phase cell cycle arrest. Taken together, these data demonstrate that inhibition of NPM has a significant effect on the cell cycle.展开更多
Background Nucleophosmin plays a critical role in embryonic development. This study aimed to examine the expression pattern of nucleophosmin in glandular epithelium of human endometrium during the menstrual cycle. Met...Background Nucleophosmin plays a critical role in embryonic development. This study aimed to examine the expression pattern of nucleophosmin in glandular epithelium of human endometrium during the menstrual cycle. Methods Endometrial tissues used for this study were obtained from 46 non-pregnant patients who underwent hysterectomy which had been performed to treat benign diseases. Nucleophosmin expression was assessed by in situ hybridization and immunohistochemistry. Results At the early-, mid- and late-proliferative phase, nucleophosmin mRNA was highly expressed in glandular epithelium of human endometrium. At the secretory phase, the expression of nucleophosmin mRNA was reduced in glandular epithelium in early-secretory phase, and the expression in mid- and late-secretory phases was not detected. Similarly, nucleophosmin protein was strongly expressed in endometrial glands throughout the proliferative phase, but was gradually reduced during secretory phase. Conclusion Nucleophosmin mRNA and protein are expressed in glandular epithelium of human endometrium throucIhout the menstrual cycle.展开更多
Objective:Pancreatic ductal adenocarcinoma(PDAC)is a highly malignant gastrointestinal cancer with a 5-year survival rate of only 9%.Of PDAC patients,15%-20%are eligible for radical surgery.Gemcitabine is an important...Objective:Pancreatic ductal adenocarcinoma(PDAC)is a highly malignant gastrointestinal cancer with a 5-year survival rate of only 9%.Of PDAC patients,15%-20%are eligible for radical surgery.Gemcitabine is an important chemotherapeutic agent for patients with PDAC;however,the efficacy of gemcitabine is limited due to resistance.Therefore,reducing gemcitabine resistance is essential for improving survival of patients with PDAC.Identifying the key target that determines gemcitabine resistance in PDAC and reversing gemcitabine resistance using target inhibitors in combination with gemcitabine are crucial steps in the quest to improve survival prognosis in patients with PDAC.Methods:We constructed a human genome-wide CRISPRa/dCas 9 overexpression library in PDAC cell lines to screen key targets of drug resistance based on sgRNA abundance and enrichment.Then,co-IP,ChIP,ChIP-seq,transcriptome sequencing,and qPCR were used to determine the specific mechanism by which phospholipase D1(PLD1)confers resistance to gemcitabine.Results:PLD1 combines with nucleophosmin 1(NPM1)and triggers NPM1 nuclear translocation,where NPM1 acts as a transcription factor to upregulate interleukin 7 receptor(IL7R)expression.Upon interleukin 7(IL-7)binding,IL7R activates the JAK1/STAT5 signaling pathway to increase the expression of the anti-apoptotic protein,BCL-2,and induce gemcitabine resistance.The PLD1 inhibitor,Vu0155069,targets PLD1 to induce apoptosis in gemcitabine-resistant PDAC cells.Conclusions:PLD1 is an enzyme that has a critical role in PDAC-associated gemcitabine resistance through a non-enzymatic interaction with NPM1,further promoting the downstream JAK1/STAT5/Bcl-2 pathway.Inhibiting any of the participants of this pathway can increase gemcitabine sensitivity.展开更多
文摘To explore the existence and distribution of nucleophosmin in the nuclear matrix and its co-localization with the other related gene products following HMBA treatment in the human hepatocarcinoma SMMC-7721 cells,the nuclear matrix of SMMC-7721 cells was extracted pre/post HMBA induced differentiation.2D PAGE proteomics analyses showed that nucleophosmin existed in the fractions of nuclear matrix proteins and was down-regulated after HMBA treatment with further confirmation by Western blot analysis.The immunofluorescence observation revealed that nucleophosmin located in the nuclear matrix,HMBA treatment altered its expression level and distribution profile.The co-localization of nucleophosmin with cancer-related genes and the products of oncogenes or tumor repression genes,including c-fos,c-myc,p53 and Rb,using laser scanning confocal microscopy,were evaluated,and substantial differences were observed following HMBA treatment.The results implies that nucleophosmin,as a nuclear matrix protein,the level of its expression and the colocalization with cancer-related gene products may play an important role during the differentiation of SMMC-7721 cell.
文摘The behavior of UBF (upstream binding factor) and nucleophosmin in HeLa and HeLa-Bcl-2 cells during apoptosis induced by TNF-α, emetine, and their mixture was investigated. A pronounced apoptosis was achieved only in HeLa cells treated with a mixture of the inducers. Immunoblotting analysis of UBF and nucleophosmin in samples containing different portions of cells with apoptotic nuclei was carried out. It showed that UBF was proteolytically cleaved giving a stable 76-kDa fragment. Increasing content of the fragment during apoptosis correlated with the level of cells containing apoptotic nuclei and with a decrease in the content of full-sized UBF. Determination of N- and C-terminal sequences of UBF and 76-kDa fragment allowed us not only to characterize UBF at the protein level, but also to describe the site of the apoptosis-specific proteolysis. Nucleophosmin did not undergo proteolytic cleavage during apoptosis and its content was unchanged even in a sample containing 100% of cells with apoptotic nuclei. However in cells reached terminal stages of apoptosis, the balance between mono- and oligomeric forms of nucleophosmin changed due to depletion of monomeric forms and appearance of two additional oligomeric forms with lower molecular weight.
基金supported by grants from theNational Natural Science Foundation of China (No.81172345 and No. 30973506)the National High Technology Research and Development Program of China (863 Program) (2006AA02A404 to Y-X.Z.)
文摘Nucleophosmin/B23 (NPM) is a universally expressed nucleolar phosphoprotein that participates in proliferation, apoptosis, ribosome assembly, and centrosome duplication; however, the role of NPM in cell cycle regulation is not well characterized. We investigated the mechanism by which NPM is involved in cell cycle regulation. NPM was knocked down using siRNA in HepG2 hepatoblastoma cells. NPM translocation following actinomycin D (ActD) treatment was investigated using immunofluorescent staining. Expression of NPM and other factors involved in cell cycle regulation was examined by Western blotting. Cell cycle distribution was measured using flow cytometry to detect 5-ethynyl-2′-deoxyuridine (EdU) incorporation. Cell proliferation was quantified by the MTT assay. Knockdown of NPM increased the percentage of HepG2 cells in S phase and led to decreased expression of P53 and P21Cip1/WAF1. S-phase arrest in HepG2 cells was significantly enhanced by ActD treatment. Furthermore, knockdown of NPM abrogated ActD-induced G2/M phase cell cycle arrest. Taken together, these data demonstrate that inhibition of NPM has a significant effect on the cell cycle.
文摘Background Nucleophosmin plays a critical role in embryonic development. This study aimed to examine the expression pattern of nucleophosmin in glandular epithelium of human endometrium during the menstrual cycle. Methods Endometrial tissues used for this study were obtained from 46 non-pregnant patients who underwent hysterectomy which had been performed to treat benign diseases. Nucleophosmin expression was assessed by in situ hybridization and immunohistochemistry. Results At the early-, mid- and late-proliferative phase, nucleophosmin mRNA was highly expressed in glandular epithelium of human endometrium. At the secretory phase, the expression of nucleophosmin mRNA was reduced in glandular epithelium in early-secretory phase, and the expression in mid- and late-secretory phases was not detected. Similarly, nucleophosmin protein was strongly expressed in endometrial glands throughout the proliferative phase, but was gradually reduced during secretory phase. Conclusion Nucleophosmin mRNA and protein are expressed in glandular epithelium of human endometrium throucIhout the menstrual cycle.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFA1201100)the National Natural Science Foundation of China(Grant Nos.82103006,82030092,81720108028,82072657,82072716,82103003,82173295,81871968,81871978,82072691,and 82103222)+1 种基金the Tianjin Hygiene Healthy Science and Technology Project(Grant No.TJWJ2022MS007)the Science&Technology Development Fund of Tianjin Education Commission for Higher Education(Grant No.2020KJ141).
文摘Objective:Pancreatic ductal adenocarcinoma(PDAC)is a highly malignant gastrointestinal cancer with a 5-year survival rate of only 9%.Of PDAC patients,15%-20%are eligible for radical surgery.Gemcitabine is an important chemotherapeutic agent for patients with PDAC;however,the efficacy of gemcitabine is limited due to resistance.Therefore,reducing gemcitabine resistance is essential for improving survival of patients with PDAC.Identifying the key target that determines gemcitabine resistance in PDAC and reversing gemcitabine resistance using target inhibitors in combination with gemcitabine are crucial steps in the quest to improve survival prognosis in patients with PDAC.Methods:We constructed a human genome-wide CRISPRa/dCas 9 overexpression library in PDAC cell lines to screen key targets of drug resistance based on sgRNA abundance and enrichment.Then,co-IP,ChIP,ChIP-seq,transcriptome sequencing,and qPCR were used to determine the specific mechanism by which phospholipase D1(PLD1)confers resistance to gemcitabine.Results:PLD1 combines with nucleophosmin 1(NPM1)and triggers NPM1 nuclear translocation,where NPM1 acts as a transcription factor to upregulate interleukin 7 receptor(IL7R)expression.Upon interleukin 7(IL-7)binding,IL7R activates the JAK1/STAT5 signaling pathway to increase the expression of the anti-apoptotic protein,BCL-2,and induce gemcitabine resistance.The PLD1 inhibitor,Vu0155069,targets PLD1 to induce apoptosis in gemcitabine-resistant PDAC cells.Conclusions:PLD1 is an enzyme that has a critical role in PDAC-associated gemcitabine resistance through a non-enzymatic interaction with NPM1,further promoting the downstream JAK1/STAT5/Bcl-2 pathway.Inhibiting any of the participants of this pathway can increase gemcitabine sensitivity.
