Phosphatase and tensin homology deleted in chromosome 10,hypoxia-inducible factor-1 alpha gene expression in colorectal adenoma and adenocarcinoma and their relation to vascular endothelial growth factor protein expression

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 (χ2= 4.751 ,P<0.05),but negatively with the PTEN mRNA expression(χ2=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.

Nerve growth factor pretreatment against glutamate-induced hippocampal neuronal injury Action mechanism of phosphatase and tensin homologue deleted on chromosome 10

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.

Rapid construction of phosphatase and tensin homolog-deleted on chromosome ten gene recombinant adenovirus using the AdEasy system

Recent studies have shown that phosphatase and tensin homolog-deleted on chromosome ten （PTEN） gene plays an important role in ischemic brain damage and synaptic plasticity. The AdEasy system, which has been widely used, greatly simplifies preparation of recombinant adenovirus. Therefore, recombinant defective adenovirus vector carrying human PTEN tumor suppressor gene （Ad-PTEN） was constructed using the AdEasy-1 system and was transfected into HEK293 cells for packaging and amplification. Infection efficiency and expression intensity were observed in primary cultured rat hippocampal neurons infected with Ad-PTEN in vitro. Results revealed a cytopathic effect in green fluorescent protein expression, which increased with prolonged time. After three cycles of amplification, the adenovirus titer was increased to an adequate titer for infecting hippocampal neurons. The entire process typically requires 4-5 weeks for completion. Results suggested that recombinant defective adenovirus vector carrying the PTEN gene was successfully and rapidly constructed using the AdEasy system.

Relationsip between PTEN and VEGF Expression and Clinicopathological Characteristics in HCC

To investigate the expressions and significance of the tumor suppressor gene phosphatase and tensin homlog deleted on chromosome ten protein （PTEN） and vascular endothelial growth factor （VEGF） in hepatocellular carcinoma （HCC）, and to analyze the relationship between their expressions and the tumor＇s invasion and their pericarcinomatous tissues, the correlation of their expressions with the tumor＇s clinicopathological characteristics and invasion potential were studied. Our study showed that the expression level of PTEN in HCC was remarkably lower than that in pericarcinomatous liver tissues, while the expressions of both VEGF and MVD were higher than that in pericarcinomatous liver tissues. Correlation analysis revealed that the expression of PTEN was negatively related to the progression of the pathological differentiation and invasion of tumor, whereas the expressions of VEGF and MVD were positively related. Moreover, there was a negative relationship between the expression of PTEN and the expressions of VEGF and MVD, and a positive one between VEGF and MVD. The expressions of PTEN and VEGF may reveal the degree of differentiation and the invasive potential of HCC tissues. The mechanism by which the lack of PTEN expression probably induces abnormal hyperexpression of VEGF may play an important role in the invasion and metastasis of HCC.

Upregulated DJ-1 Promotes Renal Tubular EMT by Suppressing Cytoplasmic PTEN Expression and Akt Activation

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.

血清TLR4和PTEN与特发性膜性肾病患者临床病理特征及预后的相关性

目的 探究血清Toll样受体4(TLR4)、第10号染色体缺失性磷酸酶和张力蛋白同源物基因(PTEN)与特发性膜性肾病(IMN)患者临床病理特征及预后的相关性。方法 选取2019年1月至2022年1月在河北以岭医院就诊治疗的IMN患者224例为IMN组,同时根据其预后结果将其分为预后良好组174例、预后不良组50例;另选取同期在本院体检健康者100名作为对照组。采用酶联免疫吸附法(ELISA)检测研究对象血清TLR4、PTEN水平;采用pearson分析IMN患者血清TLR4水平和PTEN水平相关性;多因素Logistic回归分析IMN患者预后不良的影响因素;受试者工作特征曲线(ROC)分析血清TLR4和PTEN在评估IMN患者预后中的价值。结果 IMN组血清TLR4、PTEN水平较对照组均显著升高,差异有统计学意义(t=12.918,13.249,P<0.05);预后不良组血清TLR4、PTEN水平较预后良好组均显著升高,差异有统计学意义(t=11.608,12.965,P<0.05);IMN患者血清TLR4与PTEN水平呈正相关;TLR4、PTEN、IgG、合并高血压均为IMN患者预后不良的独立危险因素(P<0.05);血清TLR4、PTEN水平预测IMN患者预后是否不良的曲线下面积(AUC)分别为0.878、0.868,两者联合预测的AUC为0.941,高于两者单独预测(z=1.874、2.065,P<0.05),且特异度为0.89,灵敏度为0.88。结论 血清TLR4、PTEN水平与IMN患者分期,肾小球硬化,二者对IMN预后具有一定的预测价值。

PTEN and Ki67 expression is associated with clinicopathologic features of non-small cell lung cancer

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.

急性脑梗死患者血清CXCL1、PTEN mRNA水平与病情严重程度及预后的关系

目的探讨急性脑梗死患者血清CXC趋化因子配体1(CXCL1)、第10染色体同源丢失性磷酸酶张力蛋白基因(PTEN)mRNA水平与病情严重程度及预后的关系。方法将2022年3月至2023年3月该院收治的102例急性脑梗死患者纳入研究作为试验组,另选取同期于该院进行体检的85例健康者作为对照组。收集纳入研究者的空腹静脉血血清标本。采用酶联免疫吸附法检测血清CXCL1水平。采用实时荧光定量PCR(qPCR)检测血清PTEN mRNA相对表达水平(下称水平)。根据美国国立卫生研究院脑卒中量表(NIHSS)评分将试验组患者分神经功能缺损程度不同的3组(重症组、中度组、轻度组),比较3组血清CXCL1、PTEN mRNA水平。根据计算机断层扫描(CT)或磁共振成像(MRI)评估脑梗死体积,将试验组患者分为小型梗死组、中型梗死组和大型梗死组,比较3组血清CXCL1、PTEN mRNA水平。根据改良Rankin量表(mRS)将试验组患者分为预后良好组和预后不良组,比较2组患者血清CXCL1、PTEN mRNA水平。采用Pearson相关分析急性脑梗死患者血清CXCL1、PTEN mRNA水平的相关性。采用多因素Logistics回归分析影响急性脑梗死患者预后的因素。结果试验组有糖尿病史、高血压史者占比及血清CXCL1、PTEN mRNA水平均高于对照组,差异均有统计学意义(P<0.05)。随着神经功能缺损程度的增加,血清CXCL1水平、PTEN mRNA水平均增加,重症组、中度组、轻度组间比较差异均有统计学意义(P<0.05)。随着梗死面积增加,血清中CXCL1、PTEN mRNA水平均增加,小型梗死组、中型梗死组和大型梗死组间比较差异均有统计学意义(P<0.05)。预后不良组有糖尿病史者占比、有高血压史者占比及血清CXCL1、PTEN mRNA水平均高于预后良好组(P<0.05)。急性脑梗死患者血清CXCL1水平和PTEN mRNA水平呈正相关(r=0.479,P<0.001)。血清CXCL1、PTEN mRNA水平及糖尿病史、高血压史均为急性脑梗死患者预后的影响因素(P<0.05)。结论急性脑梗死患者血清CXCL1、PTEN mRNA水平升高,可用于评估患者病情程度和预后。

MiR-106b-5p Inhibits Tumor Necrosis Factor-α-induced Apoptosis by Targeting Phosphatase and Tensin Homolog Deleted on Chromosome 10 in Vascular Endothelial Cells

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.

食管黏膜上皮癌变过程中与细胞骨架蛋白tensin同源的磷酸酯酶基因的表达及意义

目的探讨与细胞骨架蛋白tensin同源的磷酸酯酶基因(PTEN)在食管黏膜上皮癌变过程中的表达及意义。方法采用免疫组织化学法检测20例正常食管黏膜、20例食管上皮非典型增生、24例原位癌、44例食管鳞癌组织中PTEN表达情况,并探讨PTEN与食管鳞癌病理分级的关系。结果正常食管黏膜、非典型增生、原位癌及食管鳞癌组织中PTEN蛋白阳性表达率分别为100%、85.00%、70.83%和45.45%,原位癌、食管鳞癌组织中PTEN蛋白阳性率低于正常食管黏膜(P<0.05),食管鳞癌组织中PTEN蛋白阳性率低于原位癌和食管上皮非典型增生组织(P<0.05)。高分化、中分化及低分化食管鳞癌组织中在患者中PTEN蛋白阳性表达率分别为75.00%(15/20)、21.43%(3/14)、20.00%(2/10),高分化食管鳞癌组织中PTEN蛋白阳性表达率显著高于中分化和低分化食管鳞癌组织中(P<0.05),中分化和低分化食管鳞癌组织中PTEN蛋白阳性表达率无明显差异(P>0.05)。结论PTEN表达降低可能与食管鳞状上皮癌变有关,并可能在食管癌早期形成与发展中起有重要的作用。

联合PTEN、Gleason评分与PSA在预测前列腺癌进展中的价值

目的研究第10号染色体缺失的磷酸酶和张力蛋白同源物基因(PTEN)、Gleason评分、前列腺特异性抗原(PSA)在预测前列腺癌进展中的价值。方法应用S-P法测定29例前列腺癌(Pca)与20例前列腺增生(BPH)组织切片中PTEN蛋白的表达,回顾性研究上述Pca、BPH患者Gleason评分及PSA资料。结果BPH与Pca两组中PTEN总体表达有差异性(P<0.05),两组PSA值总体差异性显著(P<0.05)。PTEN与临床资料关系中,术前PSA<4ng/ml与>10ng/ml两组间PTEN表达有差异(P<0.05),余无差异性。Gleason评分2～4分与5～7分两组PTEN表达无差异(P>0.05),两组与8～10分组PTEN表达比较差异均有显著性(P<0.01);高分化与低分化组PTEN表达有显著差异(P<0.01);临床A、B期与C、D期PTEN表达差异性显著(P<0.01)。结论联合PTEN、Gleason评分及PSA对诊断并预测Pca进展有一定的临床意义。

MiR-200a and miR-200b target PTEN to regulate the endometrial cancer cell growth in vitro

Objective:To study whether miR-200a and miR-200b target PTEN gene expression to regulate the endometrial cancer cell growth in vitro. Methods:Endometrial cancer cells ECC-1 were cultured and transfected with the miR-200a and miR-200b mimics and inhibitors as well as the negative control mimics and inhibitors,and then the cell proliferation activity as well as the expression of PTEN and downstream genes in cells was determined; after transfection of miR-200a and miR-200b mimics as well as PTEN-3'UTR luciferase report gene plasmids,the fluorescence activity of luciferase reporter gene was determined. Results:12 h,24 h and 48 h after transfection,the cell proliferation activity of miR-200a mimics group and miR-200b mimics group were significantly higher than those of NC mimics group while the cell proliferation activity of mi R-200 a inhibitor group and miR-200b inhibitor group were significantly lower than those of NC inhibitor group; 48 h after transfection,PTEN expression in cells and PTEN-3'UTR luciferase reporter gene fluorescence activity of miR-200 a mimics group and miR-200b mimics group were significantly lower than those of NC mimics group while p-PI3K and p-Akt expression were significantly higher than those of NC mimics group; PTEN expression in cells and PTEN-3'UTR luciferase reporter gene fluorescence activity of miR-200 inhibitor group and miR-200b inhibitor group were significantly higher than those of NC inhibitor group while p-PI3K and p-Akt expression were significantly lower than those of NC inhibitor group. Conclusion:miR-200 a and miR-200b can promote the endometrial cancer cell growth in vitro by targeted inhibition of PTEN gene expression.

Anti-miRNA-221 sensitizes human colorectal carcinoma cells to radiation by upregulating PTEN

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.

Increased susceptibility of aging gastric mucosa to injury:The mechanisms and clinical implications

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.

Curcumin cytotoxicity is enhanced by PTEN disruption in colorectal cancer cells

AIM:To investigate the effects of phosphatase and tensin homolog deleted on chromosome 10(PTEN) deficiency on the cytotoxicity of chemotherapeutic agents toward colorectal cancer cells.METHODS:PTEN-deficient colorectal cancer(CRC) cells were generated by human somatic cell gene targeting using the adeno-associated virus system. The cytotoxic effects of compounds including curcumin,5-fluorouracil(5-FU),dihydroartemisinin(DHA),irinotecan(CPT-11)and oxaliplatin(OXA) on cancer cells were determined using the MTT assay. Enhanced cytotoxicity of curcumin in PTEN-deficient CRC cells was observed,and this was confirmed using clonogenic assays. Apoptosis and cell cycle progression were analyzed by flow cytometry.Levels of apoptosis and cell cycle-related proteins were examined by Western blotting.RESULTS:We developed an isogenic set of CRC cell lines that differed only in their PTEN status. Using this set of cell lines,we found that disruption of the PTEN gene had no effect on the sensitivity of CRC cells to5-FU,CPT-11,DHA,or OXA,whereas PTEN disruption increased the sensitivity of CRC cells to curcumin. Loss of PTEN did not alter the curcumin-induced apoptosis in CRC cells. However,PTEN deficiency led to an altered pattern of curcumin-mediated cell cycle arrest.In HCT116 PTEN+/+cells,curcumin caused a G2/M phase arrest,whereas it caused a G0/G1 phase arrest in HCT116 PTEN-/-cells. Levels of cell cycle-related proteins were consistent with these respective patterns of cell cycle arrest.CONCLUSION:Curcumin shows enhanced cytotoxicity toward PTEN-deficient cancer cells,suggesting that it might be a potential chemotherapeutic agent for cancers harboring PTEN mutations.

高脂血症性急性胰腺炎患者血清miR-372、PTEN水平变化及其意义

目的探讨高脂血症性急性胰腺炎(HLAP)患者血清微小RNA-372(miR-372)、第10号染色体上缺失的磷酸酶和紧张素同源物(PTEN)水平变化及其意义。方法选取150例HLAP患者为HLAP组,根据病情严重程度将HLAP患者分为轻症组(n=41)、中度重症组(n=43)、重症组(n=66),根据预后分为死亡组(n=34)和存活组(n=116);同期另选取62名体检者为对照组。采用实时荧光定量PCR法检测血清miR-372,酶联免疫吸附法检测PTEN。Pear-son相关法分析HLAP患者血清miR-372与PTEN水平的相关性,多因素Logistic回归分析HLAP患者预后不良的影响因素,受试者工作特征曲线分析血清miR-372、PTEN水平对HLAP患者预后的预测价值。结果HLAP组血清miR-372水平高于对照组,PTEN水平低于对照组(P均<0.05)。轻症组、中度重症组、重症组血清miR-372水平依次升高,PTEN水平依次降低(P均<0.05)。HLAP患者血清miR-372与PTEN水平呈负相关(r=-0.729,P<0.05)。重症HLAP、住ICU时间长和C反应蛋白、miR-372水平升高为HLAP患者预后不良的独立危险因素,PTEN升高为独立保护因素[OR(95%CI)分别为4.208(1.424~12.432)、1.724(1.243~2.390)、1.030(1.010~1.050)、1.672(1.271~2.200)、0.936(0.904~0.969)]。血清miR-372、PTEN水平联合预测HLAP患者预后的曲线下面积大于二者单独预测(P均<0.05)。结论HLAP患者血清miR-372水平升高、PTEN水平降低,二者与病情严重程度和预后有关,可作为HLAP患者预后不良的预测指标。

miR-21通过PTEN/AKT/TFEB通路对心肌梗死后心力衰竭大鼠心肌纤维化的影响

目的:探讨microRNA-21(miR-21)对心肌梗死诱导的心力衰竭大鼠心肌纤维化的影响机制。方法:SD大鼠采用结扎左冠状动脉前降支法建立心肌梗死模型,造模成功后分为模型组、重组腺相关病毒血清型9(rAAV9)-NC组、rAAV9-anti-miR-21组、rAAV9-anti-miR-21+BpV组,每组12只;另取12只大鼠作为假手术组。rAAV9-anti-miR-21组、rAAV9-NC组分别尾静脉注射含miR-21 antagomir及其阴性对照的腺病毒进行干预,rAAV9-anti-miR-21+BpV组大鼠尾静脉注射rAAV9-anti-miR-21的同时以0.2 mg/kg腹腔注射磷酸酶-张力蛋白同源物基因(PTEN)抑制剂BpV,假手术组和模型组经腹腔和尾静脉注射等体积的生理盐水,每日1次,连续干预2周。经胸超声心动图检测大鼠左心室舒张末期内径(LVEDD)和左心室收缩末期内径(LVESD),并计算左心室射血分数(LVEF)和短轴缩短分数(FS);酶联免疫吸附法(ELISA)检测血清氨基末端脑钠尿肽前体(NT-proBNP)水平;取左心室并称重,计算左心室质量指数(LVMI);马松(Masson)染色观察心肌组织病理变化;实时荧光定量聚合酶链式反应(RT-qPCR)检测左心室组织miR-21、PTEN、CollagenⅠ和CollagenⅢ表达水平;透射电子显微镜观察心肌组织自噬情况;蛋白免疫印迹法(Western Blot)检测左心室组织自噬和PTEN/蛋白激酶B(AKT)/转录因子EB(TFEB)通路相关蛋白表达。结果:与假手术组比较,模型组大鼠LVEDD、LVESD、血清NT-proBNP水平、LVMI、心肌胶原体积分数(CVF)、miR-21和CollagenⅠ、CollagenⅢ的mRNA水平以及p62蛋白水平、p-AKT/AKT比值升高,LVEF、FS、PTEN的mRNA和蛋白水平、自噬空泡的数量以及LC3Ⅱ/Ⅰ、Beclin-1、TFEB蛋白水平下降(P<0.05);与模型组比较,rAAV9-anti-miR-21组大鼠LVEDD、LVESD、血清NT-proBNP水平、LVMI、CVF、miR-21和CollagenⅠ、CollagenⅢ的mRNA水平、p62蛋白水平、p-AKT/AKT比值下降,LVEF、FS、PTEN的mRNA和蛋白水平、自噬空泡的数量以及LC3Ⅱ/Ⅰ、Beclin-1、TFEB蛋白水平升高(P<0.05);而敲低miR-21基础上应用PTEN抑制剂下调PTEN表达可降低自噬,减弱敲低miR-21对心力衰竭大鼠心肌纤维化的抑制作用。结论:miR-21在心肌梗死后心力衰竭大鼠模型中的高表达可能通过下调PTEN、激活AKT、抑制TFEB的核易位,进而抑制自噬,促进心肌纤维化。

二甲双胍对体外子宫内膜癌细胞COX-2、VEGF和PTEN表达的影响

目的探讨二甲双胍在体外对人子宫内膜癌细胞环氧合酶-2(COX-2)、血管内皮生长因子(VEGF)和张力蛋白同源第10号染色体缺失的磷酸酶(PTEN)蛋白表达的影响。方法按照二甲双胍干预药物浓度的不同,将细胞实验分为实验组(0.01 mmol/L组,0.1 mmol/L组,1 mmol/L组,10 mmol/L组)和对照组(0 mmol/L组),分别干预4种人子宫内膜癌Ishikawa、RL-952、HEC-1A和KLE细胞相同时间后,采用ELISA法检测内膜癌细胞中COX-2和VEGF表达的变化,Western blotting法检测内膜癌细胞中PTEN蛋白的表达情况。结果Ishikawa和RL-952细胞中4个实验组相对于对照组COX-2和VEGF的表达均随着二甲双胍浓度的增加呈明显下降趋势,差异均有统计学意义(P<0.05);HEC-1A和KLE细胞中4个实验组相对于对照组COX-2的表达均随着二甲双胍浓度的增加呈下降趋势,但是仅有HEC-1A细胞中10 mmol/L组差异有统计学意义(P<0.05),其余实验组差异均无统计学意义(P>0.05);HEC-1A和KLE细胞中4个实验组相对于对照组VEGF的表达均随着二甲双胍浓度的增加呈明显下降趋势,差异有统计学意义(P<0.05);Western blotting法检测显示二甲双胍能够促进子宫内膜癌Ishikawa细胞中PTEN蛋白的表达,差异有统计学意义(P<0.05),而对RL-952、HEC-1A和KLE细胞中PTEN蛋白的表达无影响(P>0.05)。结论二甲双胍可能通过抑制子宫内膜癌细胞中COX-2与VEGF的表达来实现其部分的抗肿瘤作用。

结直肠癌组织PTEN、PMS2表达水平及临床特征与预后的关系

目的探讨结直肠癌组织人第10号染色体缺失的磷酸酶(PTEN)、错配修复蛋白(PMS2)表达水平及临床特征与预后的关系。方法回顾性分析2019年4月至2021年4月在金华市中心医院行手术切除98例结直肠癌患者组织蜡块标本作为观察组,另取癌旁正常组织98例作为对照组。比较两组PTEN、PMS2阳性率的表达情况,并比较不同年龄、淋巴结转移、脉管浸润、TNM分期、肿瘤直径、分化程度结直肠癌患者的PTEN、PMS22阳性率。采用Pearson相关分析法分析结直肠癌患者PTEN、PMS2阳性率与预后的相关性。结果观察组患者的PTEN阳性率均明显低于对照组,PMS2阳性率均明显高于对照组(P<0.05);PTEN、PMS2阳性率与年龄、脉管浸润、TNM分期之间差异无统计学意义(P>0.05),在淋巴结有转移、肿瘤直径≥3 mm、低分化程度患者中,PTEN、PMS2阳性率明显高于淋巴结未转移、肿瘤直径<3 mm、中高分化程度的患者(P<0.05);随访2年后显示,预后良好有38例,预后不良有60例,预后不良组患者的PTEN阳性率均明显低于预后良好,PMS2阳性率均明显高于预后良好(P<0.05);经Pearson相关分析结果显示,PTEN阳性率与预后呈正相关、PMS2阳性率与预后呈负相关(P<0.05)。结论结直肠癌患者PTEN、PMS2阳性率有明显高表达,与患者的淋巴结转移、肿瘤直径、分化程度有关,与预后有明显的相关性,可成为今后诊治结直肠癌提供新靶点。

PTEN inhibitor bisperoxovanadium protects against noise-induced hearing loss

Studies have shown that phosphatase and tensin homolog deleted on chromosome ten(PTEN)participates in the regulation of cochlear hair cell survival.Bisperoxovanadium protects against neurodegeneration by inhibiting PTEN expression.However,whether bisperoxovanadium can protect against noise-induced hearing loss and the underlying mechanism remains unclear.In this study,we established a mouse model of noise-induced hearing loss by exposure to 105 dB sound for 2 hours.We found that PTEN expression was increased in the organ of Corti,including outer hair cells,inner hair cells,and lateral wall tissues.Intraperitoneal administration of bisperoxovanadium decreased the auditory threshold and the loss of cochlear hair cells and inner hair cell ribbons.In addition,noise exposure decreased p-PI3K and p-Akt levels.Bisperoxovanadium preconditioning or PTEN knockdown upregulated the activity of PI3K-Akt.Bisperoxovanadium also prevented H_(2)O_(2)-induced hair cell death by reducing mitochondrial reactive oxygen species generation in cochlear explants.These findings suggest that bisperoxovanadium reduces noise-induced hearing injury and reduces cochlear hair cell loss.