BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neur...BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neuronal apoptosis. However, effects of PTEN in NGF-mediated neuroprotection against glutamate excitotoxicity remain poorly understood. OBJECTIVE: To investigate the relationship between NGF inhibition of glutamate-induced injury and PTEN. DESIGN, TIME AND SE'I'rlNG: The randomized, controlled, in vitro study was performed at the Department of Pathophysiology, Medical School of Nantong University, China from October 2007 to March 2008. MATERIALS: Glutamate, NGF, 4, 6-diamidino-2-phenyl-indolediacetate, 3-[4, 5-dimethylthiazol-2-yl]- 2, 5-diphenyl tetrazoliumbromide (M-I-F), and lactate dehydrogenase kit (Sigma, USA), fluorescence microscope and inverted phase contrast microscope (Olympus, Japan) were used in this study. METHODS: Hippocampal neurons were obtained from newborn (〈 24 hours) Sprague Dawley rats and cultured for 7 days. The control group was not treated with any intervention factor, the glutamate group was treated with glutamate (0.2 mmol/L), and NGF groups were treated with NGF (10, 50, 100, and 200 μg/L, respectively) prior to glutamate treatment. MAIN OUTCOME MEASURES: The MTT and lactate dehydrogenase assays were applied to evaluate viability of hippocampal neurons. Morphological changes in hippocampal neurons were observed using an inverted phase-contrast microscope, and neuronal apoptosis was detected by 4, 6-diamidino-2- phenyl-indolediacetate staining. PTEN mRNA and protein expression were measured by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. RESULTS: Glutamate (0.2 mmol/L) induced significantly decreased neuronal viability and greater lactate dehydrogenase efflux compared with the control group (P 〈 0.01). However, compared with the glutamate group, cell viability significantly increased and lactate dehydrogenase efflux decreased in the NGF group with increasing NGF concentrations (P 〈 0.05 or P 〈 0.01). The apoptotic ratio and PTEN mRNA and protein expression decreased in the NGF group compared with the glutamate group (P 〈 0.01). CONCLUSION: Pretreatment with NGF exerted neuroprotective effects against glutamate-induced injury, partially through inhibition of PTEN expression and neuronal apoptosis.展开更多
To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein express...To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein expression in the patients with human colorectal adenomas and adenocarcinomas.Methods The expression of PTEN,HIF-1 alpha gene was detected by using in situ hybridization,and the VEGF expression levels by immunohistochemistry in colorectal adenomas and primary colorectal adenocarcinoma.Results Strong expression of HIF-1 alpha was detectable in the majority of colorectal dadenocarcinoma,particularly surrounding areas of necrosis in adenocarcinoma.PTEN,HIF-1 alpha mRNA and VEGF protein were positive in 51.6%,67.7% and 59.7% respectively in 62 cases of adenocarcinomas,and 77.8%,44.4% and 33.3% respectively in 18 cases of adenomas.The positive rate of VEGF was higher in the patients with colorectal adenocarcinomas than that in those with adenomas,whereas that of PTEN mRNA was contrary.HIF-1 mRNA expression was correlated significantly with lymph node metastasis,liver metastasis,Duke’s stage and recurrence.During colorectal tumor progression,the expression of HIF-1 alpha mRNA was positively correlated with the VEGF protein expression (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=21.84,P<0.01).Conclusion The absence or low expression of PTEN and the increased levels of HIF-1α and VEGF may paly an important role in carcinogenesis and progression of colorectal carcinoma.These results suggest that VEGF upregulated by HIF-1 alpha gene may be involved in angiogenesis of colorectal adenocarcinoma.4 refs,1 tab.展开更多
Phosphatase and tensin homolog deleted on chromosome 10(PTEN) and the proliferating antigen Ki67 have been widely studied in several tumors.However,their role as indicator in non-small cell lung cancer(NSCLC)remai...Phosphatase and tensin homolog deleted on chromosome 10(PTEN) and the proliferating antigen Ki67 have been widely studied in several tumors.However,their role as indicator in non-small cell lung cancer(NSCLC)remains unknown.Here,we investigated the expression of PTEN and Ki67 in NSCLC tissues and paired normal lung tissues to identify whether these proteins are associated with lung cancer development and survival.Immunohistochemistry for PTEN and Ki67 was performed on 67 lung cancer tissues and 41 paired adjacent normal lung tissues to detect the expression of these two proteins.The expression of PTEN in NSCLC tissues(32.8%) was significantly lower than that in normal tissues(82.9%,P 〈 0.05).In contrast,the expression of Ki67 in NSCLC tissues(76.1%) was significantly higher than that in normal tissues(27.3%,P 〈 0.05).Expression of both PTEN and Ki67 were strongly associated with tumor histology,clinical stage,lymph node metastasis,differentiation and4-year postoperative survival rate(P 〈 0.05).However,PTEN expression was negatively correlated with Ki67 expression(r =-0.279,P 〈 0.05).In conclusion,low PTEN expression and Ki67 overexpression are associated with malignant invasion and lymph node metastasis of NSCLC.These proteins may serve as diagnostic and prognostic biomarkers of NSCLC.展开更多
This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-...This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-“aging gastropathy”-has prominent structural and functional abnormalities vs young gastric mucosa. Some of these abnormalities include a partial atrophy of gastric glands, impaired mucosal defense (reduced bicarbonate and prostaglandin generation, decreased sensory innervation), increased susceptibility to injury by a variety of damaging agents such as ethanol, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), impaired healing of injury and reduced therapeutic efficacy of ulcer-healing drugs. Detailed analysis of the above changes indicates that the following events occur in aging gastric mucosa: reduced mucosal blood flow and impaired oxygen delivery cause hypoxia, which leads to activation of the early growth response-1 (egr-1) transcription factor. Activation of egr-1, in turn, upregulates the dual specificity phosphatase, phosphatase and tensin homologue deleted on chromosome ten (PTEN) resulting in activation of pro-apoptotic caspase-3 and caspase-9 and reduced expression of the anti-apoptosis protein, survivin. The imbalance between pro- and anti-apoptosis mediators results in increased apoptosis and increased susceptibility to injury. This paradigm has human relevance since increased expression of PTEN and reduced expression of survivin were demonstrated in gastric mucosa of aging individuals. Other potential mechanisms operating in aging gastric mucosa include reduced telomerase activity, increase in replicative cellular senescence, and reduced expression of vascular endothelial growth factor and importin-α-a nuclear transport protein essential for transport of transcription factors to nucleus. Aging gastropathy is an important and clinically relevant issue because of: (1) an aging world population due to prolonged life span; (2) older patients have much greater risk of gastroduodenal ulcers and gastrointestinal complications (e.g., NSAIDs-induced gastric injury) than younger patients; and (3) increased susceptibility of aging gastric mucosa to injury can be potentially reduced or reversed pharmacologically.展开更多
Background: Apoptosis of endothelial cells (ECs) plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is...Background: Apoptosis of endothelial cells (ECs) plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a viable target in therapeutic approaches to prevent vascular ECs apoptosis. Aberrant miR-106b-5p expression has been reported in the plasma of patients with unstable atherosclerotic plaques. However, the role and underlying mechanism of miR-106-5p in the genesis of atherosclerosis have not been addressed. In this study, we explored the anti-apoptotic role of miR-106-5p by regulating PTEN expression in vascular ECs. Methods: Real-time reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the expression levels of miR-106b-5p in human atherosclerotic plaques and normal vascular tissues. Human umbilical vein endothelial cells (HUVEC) were transfected with miR-106b-5p mimic or negative control mimic, and apoptosis was induced by serum starvation and tumor necrosis factor-α (TN F-α) treat. Western blotting and real-time RT-PCR experiments were used to detect PTEN expression levels and TN F-α-induced apoptosis was evaluated by the activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Results: The expression ofmiR-106b-5p was significantly downregulated in plaques than in normal vascular tissues. TNF-α significantly downregulated miR-106b-5p expression levels and upregulated activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Overexpression ofmiR-106b-5p with miR-106b-5p mimic inhibited PTEN expression and TNF-α-induced apoptosis in HUVEC. Luciferase reporter assays confirmed that miR-106b-5p binds to PTEN mRNA 3' untranslated region site, Conclusion: MiR-106b-5p could inhibit the expression of PTEN in vascular ECs, which could block TNF-α-induced activation of caspase-3, thus prevent ECs apoptosis in atherosclerosis diseases.展开更多
目的探讨Y染色体性别决定区相关高迁移率组盒蛋白6(SOX6)、第10号染色体缺失的磷酸酶及张力蛋白同源基因(PTEN)在急性心肌梗死(AMI)患者血清中的表达及临床意义。方法选取2021年1月至2022年3月淄博市第一医院和淄博市中心医院收治的AMI...目的探讨Y染色体性别决定区相关高迁移率组盒蛋白6(SOX6)、第10号染色体缺失的磷酸酶及张力蛋白同源基因(PTEN)在急性心肌梗死(AMI)患者血清中的表达及临床意义。方法选取2021年1月至2022年3月淄博市第一医院和淄博市中心医院收治的AMI患者100例为研究组,根据主要不良心血管事件(MACE)发生情况将患者分为MACE组52例和非MACE组48例,选取同期于淄博市第一医院和淄博市中心医院进行健康体检的志愿者110例为对照组。检测血清PTEN和SOX6水平,用Pearson相关性分析AMI患者血清PTEN和SOX6与临床指标的相关性,用ROC曲线分析PTEN和SOX6水平对AMI及预后的诊断价值。结果与对照组比较,研究组血清SOX6 mRNA水平显著降低(0.69±0.14 vs 1.03±0.16,P<0.01),血清PTEN mRNA水平显著升高(1.56±0.15 vs 1.05±0.08,P<0.01)。与非MACE组比较,MACE组血清SOX6 mRNA水平显著降低(0.61±0.15 vs 0.78±0.13,P<0.01),血清PTEN mRNA水平显著升高(1.74±0.18 vs 1.37±0.12,P<0.01)。Pearson相关性分析显示,AMI患者血清PTEN水平与cTnI、CK-MB、Gensini评分呈正相关,血清SOX6水平与cTnI、CK-MB、Gensini评分呈负相关(P<0.01)。ROC曲线分析显示,血清SOX6和PTEN联合诊断AMI的曲线下面积为0.932(95%CI:0.889~0.962),二者联合预测AMI患者发生MACE的曲线下面积为0.933(95%CI:0.866~0.974)。结论AMI患者血清中SOX6水平下调,PTEN水平上调,二者联合检测有助于诊断AMI及预测MACE。展开更多
AIM:To investigate the regulative effect of miRNA(miR)-221 on colorectal carcinoma(CRC)cell radiosensitivity and the underlying mechanisms.METHODS:A human CRC-derived cell line was cultured conventionally and exposed ...AIM:To investigate the regulative effect of miRNA(miR)-221 on colorectal carcinoma(CRC)cell radiosensitivity and the underlying mechanisms.METHODS:A human CRC-derived cell line was cultured conventionally and exposed to different doses of X-rays(0,2,4,6 and 8 Gy).The total RNA and protein of the cells were extracted 24 h after irradiation,and the alteration of miR-221 and phosphatase and tensin homolog deleted on chromosome 10(PTEN)gene mRNA expression was detected by real-time reverse transcriptase polymerase chain reaction(PCR).The protein alteration of PTEN in the cells was detected by Western blotting.Caco2 cells were pretreated with or without anti-PTEN-siRNA prior to the addition of premiR-221 or anti-miR-221 using Lipofectamine 2000.Colony formation assay and flow cytometry analysis were used to measure the surviving cell fraction and the sensitizing enhancement ratio after irradiation.Ad-ditionally,PTEN 3′-untranslated region fragment was PCR amplified and inserted into a luciferase reporter plasmid.The luciferase reporter plasmid construct was then transfected into CRC cells together with premiR-221 or anti-miR-221,and the luciferase activity in the transfected cells was detected.RESULTS:The X-ray radiation dose had a significant effect on the expression of miR-221 and PTEN protein in human Caco2 cells in a dose-dependent manner.The miR-221 expression level improved gradually with the increase in irradiation dose,while the PTEN protein expression level reduced gradually.miR-221 expression was significantly reduced in the anti-miR-221 group compared with the pre-miR-221 and negative control groups(P<0.01).Anti-miR-221 upregulated expression of PTEN protein and enhanced the radiosensitivity of Caco2 cells(P<0.01).Moreover,the inhibitory effect was dramatically abolished by pretreatment with anti-PTEN-siRNA,suggesting that the enhancement of radiosensitivity was indeed mediated by PTEN.A significant increase of luciferase activity was detected in CRC cells that were cotransfected with the luciferase reporter plasmid construct and anti-miR-221(P<0.01).CONCLUSION:Anti-miR-221 can enhance the radiosensitivity of CRC cells by upregulating PTEN.展开更多
Recently,phosphatase and tensin homolog deleted on chromosome 10(PTEN) is suggested as a new agent in the fighting against fibrogenesis.In tumor,DJ-1 is identified as a negative regulator of PTEN.But the expression ...Recently,phosphatase and tensin homolog deleted on chromosome 10(PTEN) is suggested as a new agent in the fighting against fibrogenesis.In tumor,DJ-1 is identified as a negative regulator of PTEN.But the expression of DJ-1 and the regulation of PTEN in fibrosis are unclear.Renal fibrosis was induced in 5/6 subtotal nephrectomy rat model.Human proximal tubular epithelial cells(HKC) were treated with transforming growth factor-beta 1(TGF-β1),or transfected with DJ-1 or PTEN.Confocal microscope was used to investigate the localization of DJ-1 and PTEN.The selective phosphoinositide-3 kinase(PI3K) inhibitor,LY294002,was administered to inhibit PI3K pathway.The DJ-1 and PTEN expression,markers of epithelial-mesenchymal transition(EMT) and Akt phosphorylation were measured by RT-PCR,Western blotting or immunocytochemistry.In vitro,after HKC cells were stimulated with 10 ng/mL TGF-β1 for 72 h,the expression of DJ-1 was increased,and that of PTEN was decreased.In vivo,the same results were identified in 5/6-nephrectomized rats.In normal HKC cells,most of DJ-1 protein localized in cytoplasm,and little in nucleus.TGF-β1 upregulated DJ-1 expression in both cytoplasma and nuclei.In contrary,TGF-β1 emptied cytoplasmic PTEN protein into nucleus.Overexpression of DJ-1 decreased the expression of PTEN,promoted the activation of Akt and the expression of vimentin,and also led to the loss of cytoplasmic PTEN.Contrarily,overexpression of PTEN protected HKC cells from TGF-β1-induced EMT.In conclusion,DJ-1 is upregulated in renal fibrosis and DJ-1 mediates EMT by suppressing cytoplasmic PTEN expression and Akt activation.展开更多
基金the Natural Science Foundation of Jiangsu Province, No. BK2004048the Social Development and Technology Plan of Nantong City, No. K2008009
文摘BACKGROUND: Nerve growth factor (NGF) attenuates glutamate-induced injury to hippocampal neurons, and the human tumor suppressor gene phosphatase and tensin homologue deleted on chromosome 10 (PTEN) promotes neuronal apoptosis. However, effects of PTEN in NGF-mediated neuroprotection against glutamate excitotoxicity remain poorly understood. OBJECTIVE: To investigate the relationship between NGF inhibition of glutamate-induced injury and PTEN. DESIGN, TIME AND SE'I'rlNG: The randomized, controlled, in vitro study was performed at the Department of Pathophysiology, Medical School of Nantong University, China from October 2007 to March 2008. MATERIALS: Glutamate, NGF, 4, 6-diamidino-2-phenyl-indolediacetate, 3-[4, 5-dimethylthiazol-2-yl]- 2, 5-diphenyl tetrazoliumbromide (M-I-F), and lactate dehydrogenase kit (Sigma, USA), fluorescence microscope and inverted phase contrast microscope (Olympus, Japan) were used in this study. METHODS: Hippocampal neurons were obtained from newborn (〈 24 hours) Sprague Dawley rats and cultured for 7 days. The control group was not treated with any intervention factor, the glutamate group was treated with glutamate (0.2 mmol/L), and NGF groups were treated with NGF (10, 50, 100, and 200 μg/L, respectively) prior to glutamate treatment. MAIN OUTCOME MEASURES: The MTT and lactate dehydrogenase assays were applied to evaluate viability of hippocampal neurons. Morphological changes in hippocampal neurons were observed using an inverted phase-contrast microscope, and neuronal apoptosis was detected by 4, 6-diamidino-2- phenyl-indolediacetate staining. PTEN mRNA and protein expression were measured by reverse transcription-polymerase chain reaction and Western blot analysis, respectively. RESULTS: Glutamate (0.2 mmol/L) induced significantly decreased neuronal viability and greater lactate dehydrogenase efflux compared with the control group (P 〈 0.01). However, compared with the glutamate group, cell viability significantly increased and lactate dehydrogenase efflux decreased in the NGF group with increasing NGF concentrations (P 〈 0.05 or P 〈 0.01). The apoptotic ratio and PTEN mRNA and protein expression decreased in the NGF group compared with the glutamate group (P 〈 0.01). CONCLUSION: Pretreatment with NGF exerted neuroprotective effects against glutamate-induced injury, partially through inhibition of PTEN expression and neuronal apoptosis.
文摘To examine phosphatase and tensin homology deleted in chromosome 10 (PTEN),hypoxia-inducible factor-1 alpha (HIF-1 alpha) gene expressions and their relation to vascular endothelial growth factor(VEGF) protein expression in the patients with human colorectal adenomas and adenocarcinomas.Methods The expression of PTEN,HIF-1 alpha gene was detected by using in situ hybridization,and the VEGF expression levels by immunohistochemistry in colorectal adenomas and primary colorectal adenocarcinoma.Results Strong expression of HIF-1 alpha was detectable in the majority of colorectal dadenocarcinoma,particularly surrounding areas of necrosis in adenocarcinoma.PTEN,HIF-1 alpha mRNA and VEGF protein were positive in 51.6%,67.7% and 59.7% respectively in 62 cases of adenocarcinomas,and 77.8%,44.4% and 33.3% respectively in 18 cases of adenomas.The positive rate of VEGF was higher in the patients with colorectal adenocarcinomas than that in those with adenomas,whereas that of PTEN mRNA was contrary.HIF-1 mRNA expression was correlated significantly with lymph node metastasis,liver metastasis,Duke’s stage and recurrence.During colorectal tumor progression,the expression of HIF-1 alpha mRNA was positively correlated with the VEGF protein expression (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=21.84,P<0.01).Conclusion The absence or low expression of PTEN and the increased levels of HIF-1α and VEGF may paly an important role in carcinogenesis and progression of colorectal carcinoma.These results suggest that VEGF upregulated by HIF-1 alpha gene may be involved in angiogenesis of colorectal adenocarcinoma.4 refs,1 tab.
基金supported by Nanjing Medical University Focus Development and Natural Science Foundation of China
文摘Phosphatase and tensin homolog deleted on chromosome 10(PTEN) and the proliferating antigen Ki67 have been widely studied in several tumors.However,their role as indicator in non-small cell lung cancer(NSCLC)remains unknown.Here,we investigated the expression of PTEN and Ki67 in NSCLC tissues and paired normal lung tissues to identify whether these proteins are associated with lung cancer development and survival.Immunohistochemistry for PTEN and Ki67 was performed on 67 lung cancer tissues and 41 paired adjacent normal lung tissues to detect the expression of these two proteins.The expression of PTEN in NSCLC tissues(32.8%) was significantly lower than that in normal tissues(82.9%,P 〈 0.05).In contrast,the expression of Ki67 in NSCLC tissues(76.1%) was significantly higher than that in normal tissues(27.3%,P 〈 0.05).Expression of both PTEN and Ki67 were strongly associated with tumor histology,clinical stage,lymph node metastasis,differentiation and4-year postoperative survival rate(P 〈 0.05).However,PTEN expression was negatively correlated with Ki67 expression(r =-0.279,P 〈 0.05).In conclusion,low PTEN expression and Ki67 overexpression are associated with malignant invasion and lymph node metastasis of NSCLC.These proteins may serve as diagnostic and prognostic biomarkers of NSCLC.
基金Supported by VA Merit Review grant to Tarnawski AS
文摘This review updates the current views on aging gastric mucosa and the mechanisms of its increased susceptibility to injury. Experimental and clinical studies indicate that gastric mucosa of aging individuals-“aging gastropathy”-has prominent structural and functional abnormalities vs young gastric mucosa. Some of these abnormalities include a partial atrophy of gastric glands, impaired mucosal defense (reduced bicarbonate and prostaglandin generation, decreased sensory innervation), increased susceptibility to injury by a variety of damaging agents such as ethanol, aspirin and other non-steroidal anti-inflammatory drugs (NSAIDs), impaired healing of injury and reduced therapeutic efficacy of ulcer-healing drugs. Detailed analysis of the above changes indicates that the following events occur in aging gastric mucosa: reduced mucosal blood flow and impaired oxygen delivery cause hypoxia, which leads to activation of the early growth response-1 (egr-1) transcription factor. Activation of egr-1, in turn, upregulates the dual specificity phosphatase, phosphatase and tensin homologue deleted on chromosome ten (PTEN) resulting in activation of pro-apoptotic caspase-3 and caspase-9 and reduced expression of the anti-apoptosis protein, survivin. The imbalance between pro- and anti-apoptosis mediators results in increased apoptosis and increased susceptibility to injury. This paradigm has human relevance since increased expression of PTEN and reduced expression of survivin were demonstrated in gastric mucosa of aging individuals. Other potential mechanisms operating in aging gastric mucosa include reduced telomerase activity, increase in replicative cellular senescence, and reduced expression of vascular endothelial growth factor and importin-α-a nuclear transport protein essential for transport of transcription factors to nucleus. Aging gastropathy is an important and clinically relevant issue because of: (1) an aging world population due to prolonged life span; (2) older patients have much greater risk of gastroduodenal ulcers and gastrointestinal complications (e.g., NSAIDs-induced gastric injury) than younger patients; and (3) increased susceptibility of aging gastric mucosa to injury can be potentially reduced or reversed pharmacologically.
基金This research was funded by the National Natural Science Foundation of China (NSFC)
文摘Background: Apoptosis of endothelial cells (ECs) plays a key role in the development of atherosclerosis and there are also evidence indicated that phosphatase and tensin homolog deleted on chromosome 10 (PTEN) is a viable target in therapeutic approaches to prevent vascular ECs apoptosis. Aberrant miR-106b-5p expression has been reported in the plasma of patients with unstable atherosclerotic plaques. However, the role and underlying mechanism of miR-106-5p in the genesis of atherosclerosis have not been addressed. In this study, we explored the anti-apoptotic role of miR-106-5p by regulating PTEN expression in vascular ECs. Methods: Real-time reverse transcription polymerase chain reaction (RT-PCR) was performed to detect the expression levels of miR-106b-5p in human atherosclerotic plaques and normal vascular tissues. Human umbilical vein endothelial cells (HUVEC) were transfected with miR-106b-5p mimic or negative control mimic, and apoptosis was induced by serum starvation and tumor necrosis factor-α (TN F-α) treat. Western blotting and real-time RT-PCR experiments were used to detect PTEN expression levels and TN F-α-induced apoptosis was evaluated by the activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Results: The expression ofmiR-106b-5p was significantly downregulated in plaques than in normal vascular tissues. TNF-α significantly downregulated miR-106b-5p expression levels and upregulated activation of caspase-3 and cell DNA fragmentation levels in HUVEC. Overexpression ofmiR-106b-5p with miR-106b-5p mimic inhibited PTEN expression and TNF-α-induced apoptosis in HUVEC. Luciferase reporter assays confirmed that miR-106b-5p binds to PTEN mRNA 3' untranslated region site, Conclusion: MiR-106b-5p could inhibit the expression of PTEN in vascular ECs, which could block TNF-α-induced activation of caspase-3, thus prevent ECs apoptosis in atherosclerosis diseases.
文摘目的探讨Y染色体性别决定区相关高迁移率组盒蛋白6(SOX6)、第10号染色体缺失的磷酸酶及张力蛋白同源基因(PTEN)在急性心肌梗死(AMI)患者血清中的表达及临床意义。方法选取2021年1月至2022年3月淄博市第一医院和淄博市中心医院收治的AMI患者100例为研究组,根据主要不良心血管事件(MACE)发生情况将患者分为MACE组52例和非MACE组48例,选取同期于淄博市第一医院和淄博市中心医院进行健康体检的志愿者110例为对照组。检测血清PTEN和SOX6水平,用Pearson相关性分析AMI患者血清PTEN和SOX6与临床指标的相关性,用ROC曲线分析PTEN和SOX6水平对AMI及预后的诊断价值。结果与对照组比较,研究组血清SOX6 mRNA水平显著降低(0.69±0.14 vs 1.03±0.16,P<0.01),血清PTEN mRNA水平显著升高(1.56±0.15 vs 1.05±0.08,P<0.01)。与非MACE组比较,MACE组血清SOX6 mRNA水平显著降低(0.61±0.15 vs 0.78±0.13,P<0.01),血清PTEN mRNA水平显著升高(1.74±0.18 vs 1.37±0.12,P<0.01)。Pearson相关性分析显示,AMI患者血清PTEN水平与cTnI、CK-MB、Gensini评分呈正相关,血清SOX6水平与cTnI、CK-MB、Gensini评分呈负相关(P<0.01)。ROC曲线分析显示,血清SOX6和PTEN联合诊断AMI的曲线下面积为0.932(95%CI:0.889~0.962),二者联合预测AMI患者发生MACE的曲线下面积为0.933(95%CI:0.866~0.974)。结论AMI患者血清中SOX6水平下调,PTEN水平上调,二者联合检测有助于诊断AMI及预测MACE。
基金Supported by National Natural Science Foundation of China,No.81101896the National Research Foundation for Doctoral Program of Higher Education of China,No.20124433110010
文摘AIM:To investigate the regulative effect of miRNA(miR)-221 on colorectal carcinoma(CRC)cell radiosensitivity and the underlying mechanisms.METHODS:A human CRC-derived cell line was cultured conventionally and exposed to different doses of X-rays(0,2,4,6 and 8 Gy).The total RNA and protein of the cells were extracted 24 h after irradiation,and the alteration of miR-221 and phosphatase and tensin homolog deleted on chromosome 10(PTEN)gene mRNA expression was detected by real-time reverse transcriptase polymerase chain reaction(PCR).The protein alteration of PTEN in the cells was detected by Western blotting.Caco2 cells were pretreated with or without anti-PTEN-siRNA prior to the addition of premiR-221 or anti-miR-221 using Lipofectamine 2000.Colony formation assay and flow cytometry analysis were used to measure the surviving cell fraction and the sensitizing enhancement ratio after irradiation.Ad-ditionally,PTEN 3′-untranslated region fragment was PCR amplified and inserted into a luciferase reporter plasmid.The luciferase reporter plasmid construct was then transfected into CRC cells together with premiR-221 or anti-miR-221,and the luciferase activity in the transfected cells was detected.RESULTS:The X-ray radiation dose had a significant effect on the expression of miR-221 and PTEN protein in human Caco2 cells in a dose-dependent manner.The miR-221 expression level improved gradually with the increase in irradiation dose,while the PTEN protein expression level reduced gradually.miR-221 expression was significantly reduced in the anti-miR-221 group compared with the pre-miR-221 and negative control groups(P<0.01).Anti-miR-221 upregulated expression of PTEN protein and enhanced the radiosensitivity of Caco2 cells(P<0.01).Moreover,the inhibitory effect was dramatically abolished by pretreatment with anti-PTEN-siRNA,suggesting that the enhancement of radiosensitivity was indeed mediated by PTEN.A significant increase of luciferase activity was detected in CRC cells that were cotransfected with the luciferase reporter plasmid construct and anti-miR-221(P<0.01).CONCLUSION:Anti-miR-221 can enhance the radiosensitivity of CRC cells by upregulating PTEN.
基金supported by a grant from National Natural Sciences Foundation of China (No. 30800525)
文摘Recently,phosphatase and tensin homolog deleted on chromosome 10(PTEN) is suggested as a new agent in the fighting against fibrogenesis.In tumor,DJ-1 is identified as a negative regulator of PTEN.But the expression of DJ-1 and the regulation of PTEN in fibrosis are unclear.Renal fibrosis was induced in 5/6 subtotal nephrectomy rat model.Human proximal tubular epithelial cells(HKC) were treated with transforming growth factor-beta 1(TGF-β1),or transfected with DJ-1 or PTEN.Confocal microscope was used to investigate the localization of DJ-1 and PTEN.The selective phosphoinositide-3 kinase(PI3K) inhibitor,LY294002,was administered to inhibit PI3K pathway.The DJ-1 and PTEN expression,markers of epithelial-mesenchymal transition(EMT) and Akt phosphorylation were measured by RT-PCR,Western blotting or immunocytochemistry.In vitro,after HKC cells were stimulated with 10 ng/mL TGF-β1 for 72 h,the expression of DJ-1 was increased,and that of PTEN was decreased.In vivo,the same results were identified in 5/6-nephrectomized rats.In normal HKC cells,most of DJ-1 protein localized in cytoplasm,and little in nucleus.TGF-β1 upregulated DJ-1 expression in both cytoplasma and nuclei.In contrary,TGF-β1 emptied cytoplasmic PTEN protein into nucleus.Overexpression of DJ-1 decreased the expression of PTEN,promoted the activation of Akt and the expression of vimentin,and also led to the loss of cytoplasmic PTEN.Contrarily,overexpression of PTEN protected HKC cells from TGF-β1-induced EMT.In conclusion,DJ-1 is upregulated in renal fibrosis and DJ-1 mediates EMT by suppressing cytoplasmic PTEN expression and Akt activation.