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71.
《Urologic oncology》2015,33(3):110.e11-110.e18
ObjectivesTo evaluate the expression of molecular markers involved in epithelial-mesenchymal transition (EMT), a key process mediating the progression of malignant tumors, in non–muscle-invasive urothelial carcinoma of the bladder (NMIUCB) to clarify the significance of these markers as predictors of intravesical recurrence in patients treated with transurethral resection (TUR).Materials and methodsExpression levels of 13 EMT markers, including E-cadherin, N-cadherin, β-catenin, γ-catenin, fibronectin, matrix metalloproteinase (MMP)-2, MMP-9, Slug, Snail, TWIST, vimentin, ZEB1, and ZEB2, in TUR specimens obtained from 161 consecutive patients with NMIUCB were measured by immunohistochemical staining.ResultsOf these 13 markers, significant differences in the incidence of intravesical recurrence were noted according to expression levels of E-cadherin, N-cadherin, MMP-2, MMP-9, and TWIST. Univariate analysis also identified expression levels of E-cadherin, N-cadherin, MMP-2, MMP-9 and TWIST, in addition to the tumor size, pathological T category, and concomitant carcinoma in situ, as significant predictors of intravesical recurrence-free survival. Of these significant factors, expression levels of E-cadherin, MMP-9, and TWIST; tumor size; and concomitant carcinoma in situ appeared to be independently associated with intravesical recurrence-free survival on multivariate analysis. Furthermore, there were significant differences in recurrence-free survival according to positive numbers of these 5 independent risk factors (i.e., positive for 0 or 1 factor vs. positive for 2 factors vs. positive for 3 or more factors).ConclusionsConsideration of expression levels of EMT-associated markers in TUR specimens, in addition to conventional prognostic parameters, would contribute to the accurate prediction of intravesical recurrence following TUR for NMIUCB.  相似文献   
72.
Renal fibrosis and the origin of the renal fibroblast.   总被引:4,自引:0,他引:4  
Many studies have determined that the extent of tubulointerstitialinvolvement, particularly fibrosis, correlates better with renalfunction than glomerular changes do, thus, the extent of tubulointerstitialdamage in any given renal biopsy has important implicationsfor the renal prognosis of the patient (summarized in [1]).Tubulointerstitial fibrosis is characterized by the accumulationof extracellular matrix components including collagen typesI, III, IV, proteoglycans and fibronectin. In recent years,much controversy has been created in the nephrology communityregarding the origin of matrix-producing cells in the kidney.Several possibilities exist, including activation of residentinterstitial fibroblasts, migrating haematopoietic or mesenchymalstem cells from the bone marrow, periadventitial cells and epithelial–mesenchymaltransition (EMT) of tubular epithelial cells. This review summarizesrecent data indicating the possible origin of matrix-producingcells in the kidney, and illustrates from a clinical point of  相似文献   
73.
目的:对多种转移潜能不同的人前列腺癌细胞“上皮细胞间质转化态”(EMT)特性进行鉴定,并从粘附因素和细胞骨架蛋白角度分析其骨转移潜能获得的分子机制。方法:用W estern印迹法鉴定LNCaP及其亚细胞系C4、C4-2和ArCaP亚细胞系IF11、IA8,以及PC-3、Du145等细胞中上皮型钙粘素(E-cadherin)、神经型钙粘素(N-cadherin)和波形纤维蛋白(V im entin)的表达差异情况,并分析其在前列腺癌转移过程中的作用。结果:E-cad-herin在PC-3、LNCaP、C4、C4-2中表达较高,但在Du145、IF11、IA8中表达极低;而V im entin的表达情况恰恰与E-cadherin相反;N-cadherin在IF11、IA8细胞中呈现显著的高表达状态。结论:转移潜能不同的人前列腺癌细胞株之间存在EMT表型的表达差异,其中PC-3、LNCaP、C4、C4-2是未发生EMT改变的细胞,Du145、IF11、IA8却是EMT化的细胞。EMT表型差异蛋白在解释前列腺癌转移机制方面占据着重要地位。  相似文献   
74.
75.
目的 观察胸腺素β4(Tβ4)基因沉默对膀胱癌细胞上皮间质转化(EMT)的逆转,探讨其在肿瘤侵袭转移中的作用机制.方法 使用针对Tβ4的慢病毒载体(knti-Tβ4)转染膀胱癌细胞株T24.采用定量逆转录-聚合酶链反应(RT-PCR)、Western blot法检测Tβ4、整合素连接激酶(ILK)和上皮性标记基因E-cadherin、β-catenin的表达改变;Immunofluorescence法检测ILK、E-cadherin、β-catenin在转染后124细胞中的表达改变;细胞划痕实验、Boyden小室体外侵袭实验、AO/EB荧光染色法反映细胞转移潜能和凋亡的变化.结果 转染后48 h的T24细胞,Tp4、ILK、β-catenin mRNA或蛋白表达开始下降,以转染后96 h明显;而上皮标记基因E-cadherin在转染96h后,表达显著增加(P<0.05);Immunofluorescence显示ILK和β-catenin在细胞质、细胞核中表达减弱,而E-cadherin在胞膜中表达增强,细胞形态向正常上皮细胞转化;转染后的324细胞体外迁移能力与侵袭力下降[(10.4±1.2)%比(73.5±1.4)%],细胞凋亡增多(12.3%比36.6%).结论 肿瘤细胞中的Tβ4表达下调可以逆转肿瘤细胞的间质表型,而向正常上皮表型转化,降低肿瘤转移潜能.  相似文献   
76.
MicroRNAs (miRNAs) are short non-coding RNAs that modulate physiological and pathological processes by inhibiting target gene expression via blockade of protein translation or by inducing mRNA degradation. These miRNAs potentially regulate the expression of thousands of proteins. As a result, miRNAs have emerged rapidly as a major new area of biomedical research with relevance to kidney disease. MiRNA expression has been shown to differ between the kidney and other organs as well as between different kidney regions. Furthermore, miRNAs have been found to be functionally important in models of podocyte development, diabetic nephropathy and polycystic kidney disease. Of particular interest, podocyte-specific deletion of Dicer, a key enzyme in the biogenesis of miRNA, results in proteinuria and severe renal impairment in mice. One miRNA (miR-192) can also act as an effector of transforming growth factor-β activity in the high-glucose environment of diabetic nephropathy. Differential expression of miRNAs has been reported in kidney allograft rejection. It is anticipated that future studies involving miRNAs will generate new insights into the complex pathophysiology underlying various kidney diseases, generate diagnostic biomarkers and might be of value as therapeutic targets for progressive kidney diseases. The purpose of this review is to highlight key miRNA developments in kidney diseases and how this might influence the diagnosis and management of patients with kidney disease in the future.  相似文献   
77.
目的研究上皮间质转化(EMT)相关因子Snail、E-cadherin、N-cadherin与胃癌患者临床病理特征、预后及胃癌肿瘤起始细胞表面标志物CD133表达的关系。方法利用Western blot方法检测50例胃癌及癌旁正常胃黏膜组织中EMT相关因子及CD133蛋白的定位及定量表达,分析EMT相关因子及CD133蛋白表达与胃癌患者的临床病理学指标的关系,Spearman等级相关分析EMT相关因子和CD133表达的关系,Kaplan-Meier方法分析EMT相关因子及CD133表达与胃癌患者生存的关系。结果①胃癌组织中Snail、N-cadherin及CD133蛋白表达相对灰度值明显高于其在癌旁正常胃黏膜组织中的表达(Snail:0.599±0.114比0.259±0.108,P=0.020;N-cadherin:0.754±0.154比0.329±0.134,P=0.001;CD133:0.635±0.119比0.485±0.116,P=0.029),E-cadherin蛋白表达相对灰度值明显低于其在癌旁正常胃黏膜组织中的表达(0.378±0.123比0.752±0.156,P=0.003)。②Snail蛋白、N-cadherin蛋白表达平均相对灰度值在有血管浸润、淋巴管浸润、N3淋巴结转移及肿瘤直径≥5 cm和Ⅲ+Ⅳ期胃癌患者中的表达明显高于无血管浸润、淋巴管浸润、N0~N2淋巴结转移及肿瘤直径〈5 cm和Ⅰ+Ⅱ期的胃癌患者(P〈0.05),而E-cadherin蛋白表达平均相对灰度值在有血管浸润、淋巴管浸润、N3淋巴结转移及Ⅲ+Ⅳ期胃癌患者中的表达显著低于无血管浸润、淋巴管浸润、N0~N2淋巴结转移及Ⅰ+Ⅱ期的胃癌患者(P〈0.05),CD133蛋白表达平均相对灰度值在有淋巴管浸润、N3淋巴结转移、肿瘤直径≥5 cm和Ⅲ+Ⅳ期胃癌患者中的表达显著高于无淋巴管浸润、N0~N2淋巴结转移、肿瘤直径〈5 cm和Ⅰ+Ⅱ期的胃癌患者(P〈0.05)。③Snail、N-cadherin蛋白表达与CD133蛋白表达分别均呈正相关(rs=0.278,P=0.048;rs=0.406,P=0.003),而E-cadherin蛋白表达与CD133蛋白表达呈负相关(rs=-0.504,P=0.000)。④Snail、N-cadherin及CD133蛋白低表达组的生存时间明显长于其高表达者(P〈0.05),联合EMT相关因子和CD133蛋白表达能够最有效预测患者生存。结论EMT与胃癌肿瘤起始细胞特性之间存在明显相关,并且两者与胃癌的高侵袭的临床病理特征相关,联合EMT相关因子Snail、E-cadherin、N-cadherin与CD133能够最有效预测胃癌患者的预后。  相似文献   
78.

Background

It was previously reported that propofol, an intravenously administered hypnotic and anesthetic agent, protects organs from ischemia–reperfusion (I/R) injury. However, the underlying mechanisms are largely unknown. Glycogen synthase kinase 3β (GSK-3β) is known to play an important role in the oxidative stress–induced apoptosis. In this study, we investigated the role of GSK-3β and mitochondrial permeability transition pore (MPTP) in the protective effects of propofol against hepatic I/R injury.

Materials and methods

The left and median hepatic artery and the portal vein branches were blocked by no-damage artery clips to create the model of partial ischemia (70%), and liver lobes were subjected to warm ischemia for 30, 60, 90 min, respectively. Reperfusion of 120 min was then initiated by the removal of clamp. The MPTP opening was assessed by measuring mitochondrial large amplitude swelling and mitochondrial membrane potential.

Results

Pretreatment with propofol in conditions of hepatic I/R inhibits the apoptosis of hepatocytes as evidenced by decreased terminal deoxynucleotidyl transferase dUTP nick end labeling–positive cells. Importantly, propofol suppressed the mitochondrial GSK-3β by promoting or preserving its phosphorylation at Ser9, thus restraining the opening of MPTP and preventing the mitochondrial swell and mitochondrial membrane potential collapse.

Conclusions

Propofol protects liver from I/R injury by sustaining the mitochondrial function, which is possibly involved with the modulation of MPTP and GSK-3β.  相似文献   
79.
目的探讨线粒体-细胞色素C途径在兔非酒精性脂肪肝(non-alcoholic fatty liver disease,NAFLD)肝细胞凋亡中的作用。方法雄性日本大耳兔40只,随机分为正常对照组(8周)和NAFLD模型组(4、6、8周组),每组各10只。模型组按1.2 m L/kg皮下注射花生油,2次/周,建立日本大耳兔NAFLD模型。按各组时间点处死兔子,测定兔血清中生化指标水平;HE染色观察肝组织病理形态改变,流式细胞仪检测肝细胞凋亡率;提取肝脏线粒体,分光光度法检测线粒体通透转换孔(mitochondrial permeability transition pore,MPTP)的状态变化;免疫组织化学法检查Bcl-2、Bax、细胞色素C和caspase-3在肝组织中的表达情况;Western blot检测细胞色素C以及caspase-3含量变化。结果与正常对照组相比,模型组肝脏脂质代谢指标和相关炎症因子表达水平升高,模型组肝细胞凋亡率与对照组比较显著增加(P0.01)。造模4周时出现肝功能损伤,脂质代谢紊乱,随着NAFLD病程的发展,Bcl-2、Bax、细胞色素C和caspase-3表达量逐渐增加,线粒体通透转换孔开放率随高脂饮食饲养时间延长明显增加(P0.01)。结论线粒体-细胞色素C途径在NAFLD引起的肝细胞凋亡中起到了一定的调控作用。  相似文献   
80.
目的:明确叉头框C2(FOXC2)在结直肠癌细胞侵袭迁移中的作用。方法采用逆转录病毒感染的方法建立FOXC2稳定过表达的结直肠癌细胞株(SW480/FOXC2)及空载体对照细胞株(SW480/pBabe),显微镜下观察结直肠癌细胞形态改变。Western blot及免疫荧光法检测FOXC2过表达细胞株及对照细胞株中E‐cadherin、Vimentin、N‐cadherin的表达情况;Tr‐answ ell侵袭小室实验检测结直肠癌细胞迁移能力的改变。结果过表达后SW480细胞的形态发生了明显的变化,从原来典型的上皮细胞形状变成长梭形,类似于成纤维细胞的形态;Western Blot及免疫荧光检测结果显示,FOXC2过表达后上皮分子标志物E‐cadherin表达明显下调,而间质分子标志物Vimentin及N‐cadherin表达显著上调;Transwell侵袭实验结果显示,FOXC2过表达后结直肠癌细胞侵袭潜能明显增强。结论 FOXC2过表达能诱导结直肠癌细胞SW480发生上皮‐间质转化并增强其侵袭能力。  相似文献   
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