Critical role of Wnt5a-Ror2 signaling in motility and invasiveness of carcinoma cells following Snail-mediated epithelial-mesenchymal transition

Expression of Snail has been shown to mediate epithelial-mesenchymal transition (EMT) of epithelial cells and carcinomas, characterized by morphological alterations with disappearance and appearance of E-cadherin and vimentin, respectively. Here, we show that ectopic expression of Snail in human epidermoid carcinoma A431 cells (Snail/A431) induces the representative EMT, resulting in remarkable motile and invasive properties of the cells. Expression of Wnt5a, its receptor Ror2 and matrix metalloproteinase (MMP)-2 is induced in Snail/A431, but not in control A431 cells. Interestingly, suppressed expression of either Wnt5a or Ror2 in Snail/A431 cells results in the inhibition of in vitro cell motility and invasiveness, at least partly mediated by MMP-2, without affecting characteristics of EMT, i.e., mesenchymal morphology, and down- and up-regulations of E-cadherin and vimentin, respectively. We further show that endogenous Snail is required for sustained expression of Wnt5a, Ror2 and MMP-13 in human osteosarcoma SaOS-2 cells. The results indicate that expression of both Wnt5a and Ror2 is induced during Snail-mediated EMT or malignant progression of cancer cells and that consequently activated Wnt5a-Ror2 signaling confers highly motile and invasive properties on cancer cells. Thus, Wnt5a-Ror2 signaling can be a target of cancer therapies to prevent cancer cells from undergoing invasion and metastasis.     

Polarized M2c macrophages have a promoting effect on the epithelial-to-mesenchymal transition of human renal tubular epithelial cells

This study planned to explore the effects of M2c macrophages on epithelial-to-mesenchymal transition (EMT) of human renal proximal tubular epithelial cells (HK-2). Human monocytic leukaemia cells were induced by TPA and IL-10 to differentiate M2c macrophages. Subsequently HK-2 cells were co-cultured with the M2c macrophages in Transwell chamber. After 48?h of co-culturing the HK-2 cells were detected in the mRNA and protein expression of E-cadherin, α-SMA and vimentin with RT-PCR, immunofluorescence and Western blot respectively. Besides, the migration ability of the HK-2 cells was estimated with Transwell migration assay. ANOVA was used to compare the difference between groups and Student's t-test to conduct multiple comparisons of two groups. P?<?0.05 was considered statistically significant. The results showed that the mRNA and protein expression of α-SMA and vimentin of the HK-2 cells were increased but the E-cadherin decreased significantly after 48?h co-culturing with the M2c macrophages (P?<?0.05 or P?<?0.01). And the migration ability of HK-2 cells were also increased significantly (P?<?0.05). It may be concluded that polarized M2c macrophages may have a promoting effect on the EMT of HK-2 cells.     

Induction of epithelial-to-mesenchymal transition in proximal tubular epithelial cells on microfluidic devices

In proteinuric nephropathy, epithelial-to-mesenchymal transition (EMT) is an important mechanism that causes renal interstitial fibrosis. The precise role of EMT in the pathogenesis of fibrosis remains controversial, partly due to the absence of suitable in vitro or in vivo models. We developed two microfluidic and compartmental chips that reproduced the fluidic and three-dimensional microenvironment of proximal tubular epithelial cells in vivo. Using one microfluidic device, we stimulated epithelial cells with a flow of healthy human serum, heat-inactivated serum and complement C3a, which mimicked the flow of urine within the proximal tubule. We observed that epithelial cells exposed to serum proteins became apoptotic or developed a mesenchymal phenotype. Incubating cells with C3a induced similar features. However, cells exposed to heat-inactivated serum did not adopt the mesenchymal phenotype. Furthermore, we successfully recorded the cellular morphological changes and the process of transmigration into basement membrane extract during EMT in real-time using another three-dimensional microdevice. In conclusion, we have established a cell-culture system that mimics the native microenvironment of the proximal tubule to a certain extent. Our data indicates that EMT did occur in epithelial cells that were exposed to serum proteins, and C3a plays an essential role in this pathological process.     

The role of epithelial-to-mesenchymal transition in renal fibrosis

Epithelial-to-mesenchymal transition (EMT) involving injured epithelial cells plays an important role in the progression of fibrosis in the kidney. Tubular epithelial cells can acquire a mesenchymal phenotype, and enhanced migratory capacity enabling them to transit from the renal tubular microenvironment into the interstitial space and escape potential apoptotic cell death. EMT is a major contributor to the pathogenesis of renal fibrosis, as it leads to a substantial increase in the number of myofibroblasts, leading to tubular atrophy. However, recent findings suggest that EMT involving tubular epithelial cell is a reversible process, potentially determined by the surviving cells to facilitate the repopulation of injured tubules with new functional epithelia. Major regulators of renal epithelial cell plasticity in the kidney are two multifunctional growth factors, bone morphogenic protein-7 (BMP-7) and transforming growth factor 1 (TGF-1). While TGF-1 is a well-established inducer of EMT involving renal tubular epithelial cells, BMP-7 reverses EMT by directly counteracting TGF--induced Smad-dependent cell signaling in renal tubular epithelial cells. Such antagonism results in the repair of injured kidneys, suggesting that modulation of epithelial cell plasticity has therapeutic advantages.Abbreviations ALK Activin-like kinase - bFGF Basic fibroblast growth factor - BMP Bone morphogenic protein - ECM Extracellular matrix - EGF Epithelial growth factor - EMT Epithelial-to-mesenchymal transition - FSP1 Fibroblast specific protein 1 - IL-1 Interleukin 1 - LAP Latency-associated polypeptide - MET Mesenchymal-to-epithelial transition - MMP Matrix metalloproteinase - TBM Tubular basement membrane - TGF Transforming growth factor     

Indoxyl sulfate-induced epithelial-to-mesenchymal transition and apoptosis of renal tubular cells as novel mechanisms of progression of renal disease

Indoxyl sulfate (IS), one of the uremic toxins, is regarded to have a substantial role in the progression of chronic kidney disease (CKD). Epithelial-to-mesenchymal transition (EMT) and apoptosis of renal tubular cells are known to be the critical mechanisms of the development and aggravation of CKD. We investigated the effect of IS on EMT and apoptosis in renal proximal tubular cells, NRK-52E cells. IS significantly inhibited cell proliferation and induced cell migration with a morphological transition from cuboidal epithelial cells to spindle-shaped scattered fibroblast-like cells. IS downregulated the expressions of zonula occluden-1 and E-cadherin, whereas upregulated α-SMA expression at 48?h, which was blocked by a pretreatment of the organic anion transporter, probenecid. IS also induced apoptosis of NRK cells from a concentration of 25?μg/ml with an activation of ERK1/2 and p38 MAP kinase (MAPK). Pretreatment of ERK1/2 or p38 MAPK inhibitors, PD98059 or SB203580, resulted in no significant effect on IS-induced EMT, whereas it ameliorated IS-induced apoptosis of NRK cells. These findings suggested phenotypic transition and apoptosis as potential mechanisms of IS-induced renal damage and the differential role of MAPK activation in IS-induced EMT and apoptosis of renal tubular cells.     

阻断核心岩藻糖基化修饰抑制肾小管上皮细胞的间充质转化

目的: 探讨阻抑核心岩藻糖基化修饰对肾小管上皮细胞间充质转化(EMT)过程的影响。方法: 利用转化生长因子β₁(TGF-β₁)建立肾小管上皮HK-2细胞EMT的模型,应用RNAi技术沉默HK-2细胞的α-1,6-岩藻糖基转移酶(FUT8)基因表达,光镜下观察FUT8 基因沉默后细胞形态变化,免疫印迹及免疫细胞化学方法测定细胞表型标记物蛋白E-钙黏蛋白(E-cadherin)、N-钙黏蛋白(N-cadherin)、α-平滑肌肌动蛋白(α-SMA)和成纤维细胞特异性蛋白-1(FSP-1)的表达变化,流式细胞仪测定细胞凋亡。 结果: TGF-β₁孵育48 h后,HK-2细胞失去原有的上皮细胞形态,呈现纤维细胞形态,纤维细胞表型标记蛋白α-SMA、FSP-1及N-cadherin表达明显升高,而上皮细胞表型标记蛋白E-cadherin表达明显下降,同时伴有 FUT8 基因表达上调,细胞凋亡增加,而提前转染FUT8 siRNA能明显减弱上述这些反应。结论: FUT8催化的核心岩藻糖基化修饰参与HK-2细胞的EMT过程;阻断核心岩藻糖基化修饰,能有效阻断肾小管上皮细胞的EMT过程。     

实验性肾小管间质纤维化中肾小管上皮细胞表型转化的研究

目的 观察和研究肾小管间质纤维化过程中肾小管上皮细胞发生表型转化的现象及其形态特点。方法 结扎大鼠一侧肾静脉,制作大鼠肾小管间质纤维化模型,连续饲养25d。每5d杀检5只,对肾脏重点检查,未结扎肾静脉的对侧肾作为对照,采用光镜、透射电镜、偏振光显微镜及免疫组织化学方法[链霉素抗生物素蛋白一过氧化物酶(sP)法]观察肾组织的病理变化以及肾小管上皮细胞的表型转化情况。结果肾静脉结扎侧肾逐渐出现肾小管萎缩,肾间质淋巴、单核细胞浸润和纤维化等肾小管间质纤维化的典型病变。免疫组织化学观察发现,随着病变的发展,损伤的肾小管上皮细胞角蛋白表达逐渐减弱,而a平滑肌肌动蛋白、波形蛋白、转化生长因子β1和Ⅰ、Ⅲ型胶原的表达逐渐增强,肾间质中也出现角蛋白阳性的间质细胞。透射电镜下可见肾小管上皮细胞内线粒体减少,内质网和微丝增多,并可见肾小管上皮细胞突破基底膜游离到肾间质中。天狼星红染色偏振光显微镜观察显示早期肾间质中Ⅲ型胶原增生为主,后期以Ⅰ型胶原为主。结论 在大鼠肾小管间质纤维化病变的发生和发展中,肾小管上皮细胞可转化为间质成纤维细胞,是成纤维细胞的来源之一。     

单核巨噬细胞对肾小管上皮细胞的活化作用及其机制初探

目的:观察外周血单核巨噬细胞(MO/MAC)条件培养基(M-CM)对肾小管上皮细胞(RTEC)直接作用的生物学效应并探讨可能的作用机制。方法:应用正常人外周血M-CM刺激人近端肾小管上皮细胞(HK-2),以[³H]-TdR掺入法检测HK-2细胞DNA合成、Westernblot法检测骨桥蛋白(OPN)和α-平滑肌肌动蛋白(α-SMA)表达、间接抑制ELISA法检测纤连蛋白(FN)分泌。进一步采用白细胞介素-10(IL-10)和转化生长因子-β₁(TGF-β₁)中和抗体进行拮抗。结果:①M-CM可促进HK-2细胞DNA合成、α-SMA表达及FN分泌。②TGF-β₁中和抗体(5mg/L)与M-CM同时作用于HK-2细胞,其α-SMA表达和FN分泌均明显低于M-CM单独作用组。③IL-10(20μg/L)与M-CM同时作用组的HK-2细胞,α-SMA表达和FN分泌亦明显低于M-CM组;IL-10预孵育MO/MAC组,HK-2细胞α-SMA表达也明显低于M-CM组。结论:单核巨噬细胞可直接诱导肾小管上皮细胞增殖、表型转化以及分泌细胞外基质增加;其分泌的TGF-β₁及炎性细胞因子可能参与介导上述效应。     

Dissection of key events in tubular epithelial to myofibroblast transition and its implications in renal interstitial fibrosis

Myofibroblast activation is a key event playing a critical role in the progression of chronic renal disease. Emerging evidence suggests that myofibroblasts can derive from tubular epithelial cells by an epithelial to mesenchymal transition (EMT); however, the details regarding the conversion between these two cell types are poorly understood. Here we dissect the key events during the process of EMT induced by transforming growth factor-beta1. Incubation of human tubular epithelial cells with transforming growth factor-beta1 induced de novo expression of alpha-smooth muscle actin, loss of epithelial marker E-cadherin, transformation of myofibroblastic morphology, and production of interstitial matrix. Time-course studies revealed that loss of E-cadherin was an early event that preceded other alterations during EMT. The transformed cells secreted a large amount of matrix metalloproteinase-2 that specifically degraded tubular basement membrane. They also exhibited an enhanced motility and invasive capacity. These alterations in epithelial phenotypes in vitro were essentially recapitulated in a mouse model of renal fibrosis induced by unilateral ureteral obstruction. Hence, these results indicate that tubular epithelial to myofibroblast transition is an orchestrated, highly regulated process involving four key steps including: 1) loss of epithelial cell adhesion, 2) de novo alpha-smooth muscle actin expression and actin reorganization, 3) disruption of tubular basement membrane, and 4) enhanced cell migration and invasion.     

RTN1A通过ERK信号诱导肾小管上皮细胞分泌VEGF和IL-8并促进糖尿病肾病肾纤维化

目的:探讨网状蛋白1A(RTN1A)对肾小管上皮细胞分泌血管内皮生长因子(VEGF)和白细胞介素8(IL-8)及糖尿病肾病(DN)肾纤维化的影响及潜在机制。方法:构建DN小鼠模型,并检测其血糖、肾脏指数、尿微量白蛋白和肌酐清除率进行验证; Western blot检测RTN1A、p-ERK、ERK、细胞因子VEGF和IL-8以及肾脏纤维化标志物α-平滑肌肌动蛋白(α-SMA)和纤维连接蛋白(FN)的表达;高糖处理人肾小管上皮细胞株HK-2模拟体内DN细胞,Western blot和ELISA检测ERK信号蛋白、纤维化标志物及细胞因子分泌变化;高糖联合沉默RTN1A或ERK抑制剂PD98059处理24 h,检测细胞因子的分泌和纤维化蛋白的变化。结果:DN小鼠模型中血糖、肾脏指数、尿微量白蛋白和肌酐清除率均明显高于对照组,说明DN模型构建成功; DN模型小鼠中RTN1A及其下游蛋白p-ERK的水平显著增加,并且细胞因子VEGF和IL-8及纤维化标志物α-SMA和FN也显著增加;高糖处理HK-2细胞后,细胞中RTN1A及其下游蛋白p-ERK水平升高,细胞因子VEGF和IL-8及纤维化标志物α-SMA和FN也显著升高;而ERK抑制剂PD98059处理与沉默RTN1A结果一致,p-ERK、VEGF、IL-8、α-SMA和FN均明显降低。结论:RTN1A可能与DN发生发展有关。沉默RTN1A可能通过ERK信号抑制DN肾炎症反应及纤维化。RTN1A可能是一个有效的治疗靶点。     

Hyaluronan attenuates transforming growth factor-beta1-mediated signaling in renal proximal tubular epithelial cells

Increased expression of hyaluronan (HA) has been associated with both acute renal injury and progressive renal disease, although the functional significance of this remains unclear. There is overwhelming evidence that transforming growth factor (TGF)-beta1 is critical to the development of progressive renal disease. Recent studies suggest an interaction between HA and TGF-beta signaling in cancer cell biology. The aim of this study was to examine the potential role of HA as a modulator of TGF-beta1 function in renal proximal tubular epithelial cells (PTC). Under resting conditions, co-localization of the principal receptor for HA, CD44, and both the TGF-beta type I and type II receptors was demonstrated by immunoprecipitation and western analysis and further confirmed by immunocytochemistry and confocal microscopy. Stimulation of PTC with TGF-beta1 led to increased synthesis of both type III and type IV collagen assessed by Western analysis. Addition of HA did not alter collagen synthesis, but abrogated TGF-beta1-mediated increase in type III and type IV collagen. This effect was blocked by the addition of a blocking antibody to CD44 and also by inhibition of MAP kinase kinase (MEK) activity. Furthermore HA decreased TGF-beta1 activation of a luciferase-SMAD responsive construct, and decreased translocation of SMAD4 into the cell nucleus. We have previously demonstrated an anti-migratory effect of TGF-beta1 in a scratch wounding model. As with HA antagonism of TGF-beta1 extracellular matrix generation, HA reduced the anti-migratory effect of TGF-beta1 in a CD44-dependent manner. In contrast to the effect of TGF-beta1 on collagen synthesis, which is SMAD-dependent, the anti-migratory effect of TGF-beta1 in this model is known to be dependent of activation of RhoA. In the presence of HA, TGF-beta1-mediated activation of RhoA was also abrogated in a CD44-dependent manner. The results suggest that co-localization of CD44 and TGF-beta receptors facilitate modulation of both SMAD and non-SMAD-dependent TGF-beta1-mediated events by HA. Our results therefore suggest that alteration of HA synthesis may represent an endogenous mechanism to limit renal injury.     

Genistein ameliorates parathyroid hormone-induced epithelial-to-mesenchymal transition and inhibits expression of connective tissue growth factor in human renal proximal tubular cells

Introduction

Genistein, a soybean and soy-based product, has been reported to inhibit the growth of a wide range of cancer cells, but there is no evidence concerning its treatment of chronic kidney disease. The aim was to investigate whether genistein has potential to inhibit parathyroid hormone (PTH)-induced renal interstitial fibrosis.

Material and methods

Using human renal tubular epithelial HK-2 cells, α-smooth muscle actin (α-SMA) was assessed by using immunofluorescence detection. α-Smooth muscle actin, E-cadherin and connective tissue growth factor (CTGF) were measured by Western blot analysis. The promoter activity of the CTGF gene was examined by the luciferase reporter assay.

Results

When cells were treated with PTH (0.1 nM) for 48 h, α-SMA protein expression was induced significantly, the protein expression of E-cadherin decreased substantially, and the promoter activity of the CTGF gene as well as its mRNA and protein expression levels increased (p < 0.01). Interestingly, genistein effectively inhibited PTH-induced α-SMA expression, restored E-cadherin expression, decreased mRNA and protein expression of CTGF, and suppressed the promoter activity of CTGF in a dose-dependent manner.

Conclusions

Genistein has the ability to block the biomarker for renal transdifferentiation and epithelial-to-mesenchymal transition, α-SMA, following PTH treatment and inhibit CTGF expression in human renal tubular epithelial cells; these might be important modes of actions that contribute to genistein anti-fibrogenic effects and may have great implications for its potential in clinical treatment of renal interstitial fibrosis.     

白细胞介素2对淋巴细胞特异性蛋白酪氨酸激酶在肾小管上皮细胞中表达的影响

目的：探讨IL-2对肾小管上皮细胞中淋巴细胞特异性蛋白酪氨酸激酶（Lck） mRNA及蛋白表达的影响以及Lck在狼疮肾炎中的致病作用.方法：采用BALB/c小鼠及BXSB狼疮小鼠肾小管上皮细胞为实验对象,分别给予 IL-2（100 U/ml）刺激.应用逆转录聚合酶链反应（RT-PCR）方法检测肾小管上皮细胞Lck mRNA的表达,免疫印迹法检测Lck蛋白的表达,比较IL-2刺激前后Lck mRNA及蛋白表达水平的变化.结果：正常BALB/c小鼠及BXSB狼疮小鼠肾小管上皮细胞中仅有微量Lck mRNA及蛋白表达,经IL-2刺激后二者的Lck mRNA及蛋白表达水平均有增加,以狼疮小鼠肾小管上皮细胞增加更为显著.结论：（1）肾小管上皮细胞中有Lck基因的表达.（2）肾小管上皮细胞经IL-2刺激后Lck mRNA及蛋白表达水平增加,提示IL-2可活化肾小管上皮细胞诱导Lck表达,进而可能通过一系列信号传导作用,发挥生物学作用.相对于BALB/c小鼠,狼疮小鼠肾小管上皮细胞在IL-2刺激后Lck表达更明显,提示狼疮小鼠肾小管上皮细胞可能更易激活.（3）由于Lck在狼疮肾炎小鼠肾小管上皮细胞中异常表达,推测Lck可能作为细胞因子或炎症因子的重要信号分子,促进狼疮肾炎的发生.     

Apoptosis of tubular epithelial cells in rats with chronic renal failure

Tubular injury leading to tubular atrophy and tubular loss is one of the characteristic features of chronic renal failure. To reveal the mechanism of tubular atrophy in chronic renal failure, the involvement of apoptosis was studied byin situ nick end labeling of biotinylated deoxyuridine by terminal deoxy nucleotidyl transferase (TUNEL) as well as by electron microscopy. TUNEL-positive cells and heterophagosomes containing apoptotic body-like structures having nuclear fragments with condensed chromatin were observed in the renal tubular epithelium 8 weeks after nephrectomy. It has become apparent from our study that atrophy of the tubules in chronic renal failure results, to some extent, from cell deletion by apoptosis.     

The roles of Arkadia in renal tubular epithelial to mesenchymal transition

The ubiquitin-proteasome pathway (UPP) can regulate the stability of proteins, which is regarded as an important mechanism in controlling various biological processes. In the pathway, E3 ubiquitin ligases play critical roles in the recognition of target proteins and degradation by 26S proteasomes. Arkadia is one of the E3 ubiquitin ligases, and recent research has shown that Arkadia amplifies TGF-beta signalling through degradation of Smad7. The cellular level of Smad7 plays an important role in the regulation of Smad-mediated TGF-beta signalling during progression of organ fibrosis. Studies indicate that the level of Smad7 protein expression is decreased in progression of tubulointerstitial fibrosis. Moreover, growing evidence suggests renal tubular epithelial to mesenchymal transition (EMT) plays a key role in renal tubulointerstitial fibrosis and transforming growth factor-beta(1) (TGF-beta(1)) is the most potent inducer that is capable of initiating and completing the entire EMT course. Therefore, the activation of Smad signalling induced by TGF-beta(1) plays a key role in the mechanism of renal tubular EMT, and in this process, Arkadia may has an important influence on the mechanism above mentioned through degradation of Smad7.     

淫羊藿苷通过AMPK减轻脂肪酸诱导的肾小管上皮细胞线粒体损伤

目的:探讨淫羊藿苷(icariin,ICA)对脂肪酸诱导的肾小管上皮细胞线粒体损伤的作用及其可能机制.方法:利用ICA干预棕榈酸(palmitic acid,PA)培养的大鼠肾小管上皮NRK52E细胞,实验分组为对照组、PA组、PA+ICA组及AMP活化蛋白激酶(AMP-activated protein kinase...     

葛根素注射液对糖尿病KKAy小鼠肾小管上皮细胞的影响

 目的：观察葛根素治疗糖尿病小鼠肾间质纤维化（renal interstitial fibrosis,RIF）过程中肾小管上皮-间质转化（epithelial-mesenchymal transition,EMT）相关蛋白表达的变化,为临床药物治疗糖尿病RIF提供实验依据。方法：将16只2型糖尿病模型KKAy小鼠随机分为模型组（n=8）和葛根素注射液治疗组（n=8）。8只C57BL/6J小鼠作为正常组。用药组小鼠14周龄开始以腹腔注射的方式给药,观测小鼠日常状态及血糖变化,于24周龄处死小鼠,取肾脏分别观察肾组织病理形态学变化,免疫组织化学法检测小鼠肾组织中α-平滑肌肌动蛋白(alpha-smooth muscle actin, α-SMA)、转化生长因子β1（transforming growth factor β1,TGF-β1）和转化生长因子β I型受体（TGF-β-RI）蛋白的表达。结果：形态学观察可见模型组发生明显的纤维化改变,而经葛根素注射液治疗后,小鼠肾间质基质轻度增多,病变较轻微。治疗组KKAy小鼠肾组织中较模型组小鼠肾组织中α-SMA、TGF-β1和TGF-β-RI蛋白的表达减少。结论：葛根素注射液可在一定程度上减少α-SMA的表达,抑制KKAy小鼠肾脏组织中TGF-β1和TGF-β-RI蛋白表达,阻断并逆转EMT的过程,延缓肾间质纤维化的发生和发展。     

乙肝病毒X蛋白通过激活JAK2/STAT3信号通路调节肾小管上皮细胞凋亡

 目的：观察乙肝病毒X蛋白(HBx)对肾小管上皮细胞凋亡的作用,并探讨其在乙型病毒肝炎相关性肾炎(HBVGN)发病中的分子机制。方法：将构建好的HBx真核表达载体pcDNA3.1(+)-HBx转染至体外培养的人肾近曲小管上皮细胞(HK-2细胞)中。Western blotting法检测转染后目的蛋白的表达及JAK2/STAT3信号通路的活化。细胞免疫荧光检测STAT3及p-STAT3表达水平。CCK-8法检测细胞增殖活性。Hoechst 33342染色观察细胞的形态学改变。透射电镜观察细胞的超微结构及凋亡。Annexin V/PI双染流式细胞术检测细胞凋亡率。结果：转染目的基因HBx后,p-JAK2及p-STAT3表达水平均显著增加;同时,细胞增殖明显受抑。透射电镜、Hoechst 33342染色及Annexin V/PI双染流式细胞术检测发现HBx促进HK-2细胞凋亡。AG490（JAK2/STAT3信号通路阻断剂）孵育后能够部分阻断JAK2/STAT3信号通路,减少HBx所致细胞凋亡。结论：HBx通过激活JAK2/STAT3信号通路导致肾小管上皮细胞凋亡,可能参与了HBV直接损伤肾组织的致病机制。