Objective:Increasing evidence has demonstrated that ZNF292 plays a suppressive role in cancer,however,little is known about its function and exact mechanism in esophageal squamous cell carcinoma(ESCC).Methods:Bioinfor...Objective:Increasing evidence has demonstrated that ZNF292 plays a suppressive role in cancer,however,little is known about its function and exact mechanism in esophageal squamous cell carcinoma(ESCC).Methods:Bioinformatic analysis and immunohistochemistry(IHC)were performed to analyze the role of ZNF292 in affecting the prognosis of ESCC.Cell proliferation and colony formation ability assays were performed to analyze cell growth after inferring the expression of ZNF292.Flow cytometry was used to analyze changes in the cell cycle upon the depletion of ZNF292.Quantitative real-time polymerase chain reaction(q RT-PCR)and western blot analysis were used to determine the alteration of cell cycle related RNAs and proteins after knocking down ZNF292.MG-132,cycloheximide(CHX)treatment experiments were performed to analyze the change and half-life time of P27 after knockdown of ZNF292.Chromatin immunoprecipitation(Ch IP)and luciferase reporter assays were used to analyze the transcriptional regulation of SKP2 by ZNF292.Results:We report that low expression of ZNF292 is associated with poor prognosis,and ZNF292 emerges to be highly expressed in adjacent and normal tissues rather than tumor tissues in ESCC.Knockdown of ZNF292 significantly boosts cell growth and S phase entry in ESCC cells.ZNF292 depletion will decrease the expression and half-life time of P27,while knockdown of SKP2 will result in elevated expression of P27.ZNF292 can bind to the promoter region of SKP2,and knockdown of ZNF292 will boost the expression of SKP2.Conclusions:Knockdown of ZNF292 mediates G1/S cell cycle procession by activating SKP2/P27 signaling in ESCC cells.ZNF292 knockdown promotes SKP2 expression at the transcriptional level,thereby boosting P27 ubiquitin-degradation,and eventually facilitating the S phase entrance.展开更多
AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,...AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,which serve as a model for enteroendocrine L-cells,by quantitative reverse transcription-polymerase chain reaction and Western blotting before and after treatment with oleic acid.Localization of UCP2 and GLP-1 in NCI-H716 cells was assessed by immunofluorescence labeling.NCI-H716 cells were transiently transfected with a small interfering RNA(siRNA) that targets UCP2(siUCP2) or with a nonspecific siRNA using Lipofectamine 2000.The concentrations of bioactive GLP-1 in the medium were measured by enzyme linked immunosorbent assay.RESULTS:Both GLP-1 and UCP2 granules were expressed mainly in the cytoplasm of NCI-H716 cells.NCI-H716 cells that secreted GLP-1 also expressed UCP2.Time-course experiments revealed that release of GLP-1 from NCI-H716 cells into the medium reached a maximum at 120 min and remained stable until at least 180 min after treatment with oleic acid(the level of GLP-1 increased about 2.3-fold as compared with the level of GLP-1 in the control cells,P < 0.05).In an experiment to determine dose dependence,stimulation of NCI-H716 cells with ≤ 8 mmol oleic acid led to a concentration-dependent release of GLP-1 into the medium;10 mmol oleic acid diminished the release of GLP-1.Furthermore,GLP-1 secretion induced by oleic acid from NCI-H716 cells that were transfected with siUCP2 decreased to 41.8%,as compared with NCI-H716 cells that were transfected with a non-specific siRNA(P < 0.01).CONCLUSION:UCP2 affected GLP-1 secretion induced by oleic acid.UCP2 plays an important role in L-cell secretion that is induced by free fatty acids.展开更多
Objective To construct a database of human lung squamous carcinoma cell line NCI-H226 and to facilitate discovery of novel subtypes markers of lung cancer. Method Proteomic technique was used to analyze human lung squ...Objective To construct a database of human lung squamous carcinoma cell line NCI-H226 and to facilitate discovery of novel subtypes markers of lung cancer. Method Proteomic technique was used to analyze human lung squamous carcinoma cell line NCI-H226. The proteins of the NCI-H226 cells were separated by two-dimensional gel electrophoresis and identified by mass spectrometry. Results The results showed that a good reproducibility of the 2-D gel pattern was attained. The position deviation of matched spots among three 2-D gels was 1.95±0.53 mm in the isoelectric focusing direction, and 1.73±0.45 mm in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis direction. One hundred and twenty-seven proteins, including enzymes, signal transduction proteins, structure proteins, transport proteins, etc. were characterized, of which, 29 identified proteins in NCI-H226 cells were reported for the first time to be involved in lung cancer carcinogenesis. Conclusion The information obtained from this study could provide some valuable clues for further study on the carcinogenetic mechanism of different types of lung cancer, and may help us to discover some potential subtype-specific biomarkers of lung cancer.展开更多
Objective： Even though radiotherapy plays a major role in the local treatment of non-small cell lung cancer （NSCLC）, little is known about the molecular effects of irradiation in this tumor. In the present study, w...Objective： Even though radiotherapy plays a major role in the local treatment of non-small cell lung cancer （NSCLC）, little is known about the molecular effects of irradiation in this tumor. In the present study, we examined two NSCLC cell lines for their endogenous production of TNF-α after irradiation. To investigate the radiation-induced TNF-α production in NSCLC cell lines. Methods： Two human NSCLC cell lines （A549： squamous; NCI-H596： adenosquamous） were investigated for their TNF-α mRNA （real-time RT-PCR） after exposure to different irradiation doses （2, 5, 10, 20, 30, 40 Gy） and time intervals （1, 3, 6, 12, 24, 48 or 72 h）. The TNF-α mRNA expression was quantified by real-time RT-PCR. The clonogenic survival was evaluated after irradiation with 2, 4, 6 and 8 Gy. Results： Non-irradiated NSCLC cells exhibited no or very low TNF-α expression. For the NCI-H596 cell line, TNF-α expression was significantly elevated 1～12 h （maximum 6h： 568fold increase relative to unirradiated cells） in a time-dependent manner. The radiation-induced increase could be observed after irradiation with 2 Gy reaching maximal at 40 Gy, with 83 times higher than normal controls. The clonogenic survival of these cell lines was nearly identical. Conclusion： NCI-H596 cells produce significant quantities of TNF-α following irradiation in a time- and dose-dependent manner. The pro-inflammatory cytokine TNF-α is a key mediator for the pathogenesis of radiation pneumonitis. Radiation-induced endogenous TNF-α expression in NSCLC cells may affect the normal lung adjacent to the tumor and may be associated with an adverse clinical outcome of the patient.展开更多
基金supported by the National Natural Fund of China(No.81988101,81830086 and 81972318)the Doctoral Innovation Fund of Peking Union Medical College(No.2018071011)。
文摘Objective:Increasing evidence has demonstrated that ZNF292 plays a suppressive role in cancer,however,little is known about its function and exact mechanism in esophageal squamous cell carcinoma(ESCC).Methods:Bioinformatic analysis and immunohistochemistry(IHC)were performed to analyze the role of ZNF292 in affecting the prognosis of ESCC.Cell proliferation and colony formation ability assays were performed to analyze cell growth after inferring the expression of ZNF292.Flow cytometry was used to analyze changes in the cell cycle upon the depletion of ZNF292.Quantitative real-time polymerase chain reaction(q RT-PCR)and western blot analysis were used to determine the alteration of cell cycle related RNAs and proteins after knocking down ZNF292.MG-132,cycloheximide(CHX)treatment experiments were performed to analyze the change and half-life time of P27 after knockdown of ZNF292.Chromatin immunoprecipitation(Ch IP)and luciferase reporter assays were used to analyze the transcriptional regulation of SKP2 by ZNF292.Results:We report that low expression of ZNF292 is associated with poor prognosis,and ZNF292 emerges to be highly expressed in adjacent and normal tissues rather than tumor tissues in ESCC.Knockdown of ZNF292 significantly boosts cell growth and S phase entry in ESCC cells.ZNF292 depletion will decrease the expression and half-life time of P27,while knockdown of SKP2 will result in elevated expression of P27.ZNF292 can bind to the promoter region of SKP2,and knockdown of ZNF292 will boost the expression of SKP2.Conclusions:Knockdown of ZNF292 mediates G1/S cell cycle procession by activating SKP2/P27 signaling in ESCC cells.ZNF292 knockdown promotes SKP2 expression at the transcriptional level,thereby boosting P27 ubiquitin-degradation,and eventually facilitating the S phase entrance.
基金Supported by Grant from the National Natural Science Foundation of China,No. 30771039
文摘AIM:To investigate whether uncoupling protein 2(UCP2) affects oleic acid-induced secretion of glucagonlike peptide-1(GLP-1) in L-cells.METHODS:mRNA and protein expression of UCP2 were analyzed in human NCI-H716 cells,which serve as a model for enteroendocrine L-cells,by quantitative reverse transcription-polymerase chain reaction and Western blotting before and after treatment with oleic acid.Localization of UCP2 and GLP-1 in NCI-H716 cells was assessed by immunofluorescence labeling.NCI-H716 cells were transiently transfected with a small interfering RNA(siRNA) that targets UCP2(siUCP2) or with a nonspecific siRNA using Lipofectamine 2000.The concentrations of bioactive GLP-1 in the medium were measured by enzyme linked immunosorbent assay.RESULTS:Both GLP-1 and UCP2 granules were expressed mainly in the cytoplasm of NCI-H716 cells.NCI-H716 cells that secreted GLP-1 also expressed UCP2.Time-course experiments revealed that release of GLP-1 from NCI-H716 cells into the medium reached a maximum at 120 min and remained stable until at least 180 min after treatment with oleic acid(the level of GLP-1 increased about 2.3-fold as compared with the level of GLP-1 in the control cells,P < 0.05).In an experiment to determine dose dependence,stimulation of NCI-H716 cells with ≤ 8 mmol oleic acid led to a concentration-dependent release of GLP-1 into the medium;10 mmol oleic acid diminished the release of GLP-1.Furthermore,GLP-1 secretion induced by oleic acid from NCI-H716 cells that were transfected with siUCP2 decreased to 41.8%,as compared with NCI-H716 cells that were transfected with a non-specific siRNA(P < 0.01).CONCLUSION:UCP2 affected GLP-1 secretion induced by oleic acid.UCP2 plays an important role in L-cell secretion that is induced by free fatty acids.
基金This work was supported by the National Natural Science Foundation of China (Grant No.30370712)Beijing Key Project (Grant No. 7051002).
文摘Objective To construct a database of human lung squamous carcinoma cell line NCI-H226 and to facilitate discovery of novel subtypes markers of lung cancer. Method Proteomic technique was used to analyze human lung squamous carcinoma cell line NCI-H226. The proteins of the NCI-H226 cells were separated by two-dimensional gel electrophoresis and identified by mass spectrometry. Results The results showed that a good reproducibility of the 2-D gel pattern was attained. The position deviation of matched spots among three 2-D gels was 1.95±0.53 mm in the isoelectric focusing direction, and 1.73±0.45 mm in the sodium dodecyl sulfate-polyacrylamide gel electrophoresis direction. One hundred and twenty-seven proteins, including enzymes, signal transduction proteins, structure proteins, transport proteins, etc. were characterized, of which, 29 identified proteins in NCI-H226 cells were reported for the first time to be involved in lung cancer carcinogenesis. Conclusion The information obtained from this study could provide some valuable clues for further study on the carcinogenetic mechanism of different types of lung cancer, and may help us to discover some potential subtype-specific biomarkers of lung cancer.
基金This work was supported by a grant fromChina Scholarship Council (No.20842007).
文摘Objective： Even though radiotherapy plays a major role in the local treatment of non-small cell lung cancer （NSCLC）, little is known about the molecular effects of irradiation in this tumor. In the present study, we examined two NSCLC cell lines for their endogenous production of TNF-α after irradiation. To investigate the radiation-induced TNF-α production in NSCLC cell lines. Methods： Two human NSCLC cell lines （A549： squamous; NCI-H596： adenosquamous） were investigated for their TNF-α mRNA （real-time RT-PCR） after exposure to different irradiation doses （2, 5, 10, 20, 30, 40 Gy） and time intervals （1, 3, 6, 12, 24, 48 or 72 h）. The TNF-α mRNA expression was quantified by real-time RT-PCR. The clonogenic survival was evaluated after irradiation with 2, 4, 6 and 8 Gy. Results： Non-irradiated NSCLC cells exhibited no or very low TNF-α expression. For the NCI-H596 cell line, TNF-α expression was significantly elevated 1～12 h （maximum 6h： 568fold increase relative to unirradiated cells） in a time-dependent manner. The radiation-induced increase could be observed after irradiation with 2 Gy reaching maximal at 40 Gy, with 83 times higher than normal controls. The clonogenic survival of these cell lines was nearly identical. Conclusion： NCI-H596 cells produce significant quantities of TNF-α following irradiation in a time- and dose-dependent manner. The pro-inflammatory cytokine TNF-α is a key mediator for the pathogenesis of radiation pneumonitis. Radiation-induced endogenous TNF-α expression in NSCLC cells may affect the normal lung adjacent to the tumor and may be associated with an adverse clinical outcome of the patient.
