Clinical significance of upregulated Rho GTPase activating protein 12 causing resistance to tyrosine kinase inhibitors in hepatocellular carcinoma

BACKGROUND Hepatocellular carcinoma(HCC)is a major health challenge with high incidence and poor survival rates in China.Systemic therapies,particularly tyrosine kinase inhibitors(TKIs),are the first-line treatment for advanced HCC,but resistance is common.The Rho GTPase family member Rho GTPase activating protein 12(ARHGAP12),which regulates cell adhesion and invasion,is a potential therapeutic target for overcoming TKI resistance in HCC.However,no studies on the expression of ARHGAP12 in HCC and its role in resistance to TKIs have been reported.AIM To unveil the expression of ARHGAP12 in HCC,its role in TKI resistance and its potential associated pathways.METHODS This study used single-cell RNA sequencing(scRNA-seq)to evaluate ARHGAP12 mRNA levels and explored its mechanisms through enrichment analysis.CellChat was used to investigate focal adhesion(FA)pathway regulation.We integrated bulk RNA data(RNA-seq and microarray),immunohistochemistry and proteomics to analyze ARHGAP12 mRNA and protein levels,correlating with clinical outcomes.We assessed ARHGAP12 expression in TKI-resistant HCC,integrated conventional HCC to explore its mechanism,identified intersecting FA pathway genes with scRNA-seq data and evaluated its response to TKI and immunotherapy.RESULTS ARHGAP12 mRNA was found to be highly expressed in malignant hepatocytes and to regulate FA.In malignant hepatocytes in high-score FA groups,MDK-[integrin alpha 6(ITGA6)+integrinβ-1(ITGB1)]showed specificity in ligand-receptor interactions.ARHGAP12 mRNA and protein were upregulated in bulk RNA,immunohistochemistry and proteomics,and higher expression was associated with a worse prognosis.ARHGAP12 was also found to be a TKI resistance gene that regulated the FA pathway.ITGB1 was identified as a crossover gene in the FA pathway in both scRNA-seq and bulk RNA.High expression of ARHGAP12 was associated with adverse reactions to sorafenib,cabozantinib and regorafenib,but not to immunotherapy.CONCLUSION ARHGAP12 expression is elevated in HCC and TKI-resistant HCC,and its regulatory role in FA may underlie the TKI-resistant phenotype.

Progress in researches about focal adhesion kinase in gastrointestinal tract

Focal adhesion kinase(FAK)is a 125-kDa non-receptor protein tyrosine.Growth factors or the clustering of integrins facilitate the rapid phosphorylation of FAK at Tyr-397 and this in turn recruits Src-family protein tyrosine kinases,resulting in the phosphorylation of Tyr-576 and Tyr-577 in the FAK activation loop and full catalytic FAK activation.FAK plays a critical role in the biological processes of normal and cancer cells including the gastrointestinal tract.FAK also plays an important role in the restitution,cell survival and apoptosis and carcinogenesis of the gastrointestinal tract.FAK is over-expressed in cancer cells and its over-expression and elevated activities are associated with motility and invasion of cancer cells.FAK has been proposed as a potential target in cancer therapy.Small molecule inhibitors effectively inhibit the kinase activity of FAK and show a potent inhibitory effect for the proliferation and migration of tumor cells,indicating a high potential for application in cancer therapy.

Focal adhesion kinase and Src phosphorylations in HGF-induced proliferation and invasion of human cholangiocarcinoma cell line, HuCCA-1

AIM: To study the role of focal adhesion kinase (FAK) and its association with Src in hepatocyte growth factor (HGF)-induced cell signaling in cholangiocarcinoma progression.METHODS: Previously isolated HuCCA-1 cells were re-characterized by immunofluorescent staining and reverse transcriptase-polymerase chain reaction assay for the expression of cytokeratin 19, HGF and c-Met mRNA. Cultured HuCCA-1 cells were treated with HGF and determined for cell proliferation and invasion effects by MTT and invasion assays. Western blotting, immunoprecipitation, and co-immunoprecipitation were also performed to study the phosphorylation and interaction of FAK and Src. A novel Src inhibitor (AZM555130) was applied in cultures to investigate the effects on FAK phosphorylation inhibition and on cell proliferation and invasion.RESULTS: HGF enhanced HuCCA-1 cell proliferation and invasion by mediating FAK and Src phosphorylations.FAK-Src interaction occurred in a time-dependent manner that Src was proved to be an upstream signaling molecule to FAK. The inhibitor to Src decreased FAK phosphorylation level in correlation with the reduction of cell proliferation and invasion.CONCLUSION: FAK plays a significant role in signaling pathway of HGF-responsive cell line derived from cholangiocarcinoma. Autophosphorylated Src, induced by HGF, mediates Src kinase activation, which subsequently phosphorylates its substrate, FAK, and signals to cell proliferation and invasion.

Focal adhesion kinase-related non-kinase ameliorates liver fibrosis by inhibiting aerobic glycolysis via the FAK/Ras/c-myc/ENO1 pathway

BACKGROUND Hepatic stellate cell(HSC)hyperactivation is a central link in liver fibrosis development.HSCs perform aerobic glycolysis to provide energy for their activation.Focal adhesion kinase(FAK)promotes aerobic glycolysis in cancer cells or fibroblasts,while FAK-related non-kinase(FRNK)inhibits FAK phosphorylation and biological functions.AIM To elucidate the effect of FRNK on liver fibrosis at the level of aerobic glycolytic metabolism in HSCs.METHODS Mouse liver fibrosis models were established by administering CCl4,and the effect of FRNK on the degree of liver fibrosis in the model was evaluated.Transforming growth factor-β1 was used to activate LX-2 cells.Tyrosine phosphorylation at position 397(pY397-FAK)was detected to identify activated FAK,and the expression of the glycolysis-related proteins monocarboxylate transporter 1(MCT-1)and enolase1(ENO1)was assessed.Bioinformatics analysis was performed to predict putative binding sites for c-myc in the ENO1 promoter region,which were validated with chromatin immunoprecipitation(ChIP)and dual luciferase reporter assays.RESULTS The pY397-FAK level was increased in human fibrotic liver tissue.FRNK knockout promoted liver fibrosis in mouse models.It also increased the activation,migration,proliferation and aerobic glycolysis of primary hepatic stellate cells(pHSCs)but inhibited pHSC apoptosis.Nevertheless,opposite trends for these phenomena were observed after exogenous FRNK treatment in LX-2 cells.Mechanistically,the FAK/Ras/c-myc/ENO1 pathway promoted aerobic glycolysis,which was inhibited by exogenous FRNK.CONCLUSION FRNK inhibits aerobic glycolysis in HSCs by inhibiting the FAK/Ras/c-myc/ENO1 pathway,thereby improving liver fibrosis.FRNK might be a potential target for liver fibrosis treatment.

Inhibition of focal adhesion kinase enhances antitumor response of radiation therapy in pancreatic cancer through CD8+ T cells

Objective:Pancreatic ductal adenocarcinoma(PDAC)is a deadly malignancy,due in large part to its resistance to conventional therapies,including radiotherapy(RT).Despite RT exerting a modest antitumor response,it has also been shown to promote an immunosuppressive tumor microenvironment.Previous studies demonstrated that focal adhesion kinase inhibitors(FAKi)in clinical development inhibit the infiltration of suppressive myeloid cells and T regulatory(T regs)cells,and subsequently enhance effector T cell infiltration.FAK inhibitors in clinical development have not been investigated in combination with RT in preclinical murine models or clinical studies.Thus,we investigated the impact of FAK inhibition on RT,its potential as an RT sensitizer and immunomodulator in a murine model of PDAC.Methods:We used a syngeneic orthotopic murine model to study the effect of FAKi on hypofractionated RT.Results:In this study we showed that IN10018,a small molecular FAKi,enhanced antitumor response to RT.Antitumor activity of the combination of FAKi and RT is T cell dependent.FAKi in combination with RT enhanced CD8+T cell infiltration significantly in comparison to the radiation or FAKi treatment alone(P<0.05).FAKi in combination with radiation inhibited the infiltration of granulocytes but enhanced the infiltration of macrophages and T regs in comparison with the radiation or FAKi treatment alone(P<0.01).Conclusions:These results support the clinical development of FAKi as a radiosensitizer for PDAC and combining FAKi with RT to prime the tumor microenvironment of PDAC for immunotherapy.

Inhibiting focal adhesion kinase:A potential target for enhancing therapeutic efficacy in colorectal cancer therapy

Focal adhesion kinase(FAK) is a major integrin- dep-endent tyrosine phosphorylated protein, recently, FAK association with colorectal cancer(CRC) has gained at-tention. The various cancer-promoting mechanisms that associated with FAK can be implicated in the progression of CRC. The interactions between structural features of FAK and various kinases could be closely related to growth, survival, and metastasis in CRC cells. These interactions include human epithelial growth factor re-ceptor, c-Met, platelet-derived growth factor receptor, vascular endothelial growth factor receptor, and Src. Such interactions can trigger the survival signaling of CRC cells and are also involved signaling downstream of phosphatidylinositol 3-kinase, AKT, and the extracellular regulated kinase. Based on this scientific background, many pharmaceutical companies are taking efforts to develop FAK inhibitors to treat solid cancer including CRC. Although the anti-cancer efficacies have been noted in many studies, the commercial drugs have not been deve-loped yet. Therefore, the FAK research on CRC is expec-ted to gain momentum and be highly appreciated as a potential field for developing the new drugs. Therefore, the studies on FAK that effect on the progression of human CRC s would be possible to suggest various app-roaches to CRC treatment, and FAK could be a potential target as an anticancer candidate for CRC therapies.

Effect of focal adhesion kinase on cytoskeletal arrangement of HepG2 cells induced by hypoxia

Objective： To study focal adhesion kinase （FAK） expression in hypoxic HepG2 cells and the effect of FAK siRNA on cytoskeletal arrangement of HepG2 cells induced by hypoxia. Methods： HepG2 cells were cultured in 21% O2 and 1% O2. Morphological changes were observed after hypoxia treatment. Western blot was used to measure FAK expression. The siRNA expression vector pshRNA-FAK targeting the mRNA of FAK and vector pGensil-2 （as a control） were constructed, and then transfected into HepG2 cells. Western blot was used to detect FAK. The cytoskeletal arrangement of HepG2 cells transfected with pshRNA-FAK induced by hypoxia was analyzed by phalloidin. The migratory ability of HepG2 cells transfected with pshRNA-FAK induced by hypoxia was analyzed by cell migration assay. Results： Hypoxia-treated cells displayed a more elongated shape with a large degree of cell detachment. FAK expression increased in hypoxic HepG2 cells. FAK protein level was decreased by 75.64% ± 3.12% （P 〈 0.01） after the pshRNA-FAK transfection. Hypoxia induced cytoskeletal arrangement of HepG2 cells. However, cytoskeletal arrangement of HepG2 cells transfected with pshRNA-FAK induced by hypoxia was inhibited in 1% O2. As cell migration assay showed, the migrating number of HepG cells transfected with pshRNA-FAK was significantly lower than that of control （P 〈 0.05）. Conclusion： The expression of FAK in hypoxic HCC might have a close relationship to the cytoskeletal arrangement of HepG2 cells induced by hypoxia. Up-regulation of FAK expression may be one of mechanisms of cytoskeletal arrangement and invasion of hepatocellular carcinoma induced by hypoxia.

The Overexpressed FAK （Focal Adhesion Kinase） in Higher Grade Human Urothelial Tumors

Malignant transformation of normal cells involves important structural and functional changes, particularly in cell adhesion. In this study, we wanted to assess whether changes in the expression of FAK, a tyrosine kinase, which is recruited to focal adhesions and plays a key role in cell migration, proliferation and survival, could reflect the invasive capacity of bladder carcinomas. The aim of this study was to evaluate the FAK expression in cancer ceils as an important prognostic factor of the evolution of bladder carcinomas. Tumor and paired peritumoral biopsies were obtained during transurethral endoscopic resection or cystectomy of bladder tumors in 280 patients at the Urology Unit of the Mustapha Hospital of Algiers and the Hospital of Tizi-Ouzou （Algeria）. The authors studied FAK expression in samples from bladder carcinomas at different stages of malignant transformation by western blot analysis using a specific anti-FAK antibody. Western blot is one of the most common laboratory techniques; it is used to detect the presence of a specific protein in a complex mixture extracted from cells. A weak increase in FAK expression was observed in tumors of grade 1 and 2 （1.65; 2.99） as compared to healthy tissues; it became particularly important in grade 3 tumors; the authors show that FAK levels significantly increased gradually according to the tumor stage.

黄芩素对人乳腺癌细胞系MDA-MB-231侵袭、迁移、上皮间充质转化的调控作用及其机制

目的观察黄岑素对人乳腺癌细胞系MDA-MB-231的侵袭、迁移及上皮间充质转化(EMT)的调控作用,探讨其可能作用机制。方法取对数生长期MDA-MB-231细胞分为一组、二组、三组及对照组,一组、二组、三组分别加入2.5、5、10μmol/L的黄岑素,对照组不做任何处理。培养48 h时采用划痕修复实验观察四组细胞迁移能力、采用Transwell侵袭实验观察四组细胞侵袭能力,采用Western Blotting法检测细胞EMT标志物波形蛋白(vimentin)及E-钙黏蛋白(E-cadherin)、整合素αv、β3、磷酸化黏着斑激酶(p-FAK)、磷酸化磷脂酰肌醇3激酶(整合素p-PI3K)。结果与对照组相比,黄岑素组细胞迁移率降低、侵袭细胞数少,细胞E-cadherin相对表达量高,vimentin、整合素αv、整合素β3、p-FAK、p-PI3K蛋白相对表达量低,且呈剂量依赖性(P均<0.05)。结论黄芩素抑制MDA-MB-231细胞的侵袭、迁移及EMT。黄岑素可能通过抑制整合素αv、整合素β3表达,进一步抑制p-FAK、p-PI3K蛋白表达,抑制MDA-MB-231的侵袭、迁移及EMT。

基于环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白通路探究丙泊酚对局灶性脑缺血再灌注大鼠神经功能改善机制

目的:基于环磷酸腺苷/蛋白激酶A/环磷酸腺苷反应元件结合蛋白(cAMP/PKA/CREB)通路探究丙泊酚对局灶性脑缺血再灌注大鼠神经功能的改善机制。方法:采用改良线栓法缺血2 h,再灌注24 h建立大鼠脑缺血再灌注损伤(CIRI)模型,将造模成功大鼠随机分为模型组和丙泊酚低(1 mg/ml)、中(2.5 mg/ml)、高剂量(5 mg/ml)组,各12只,另设含有12只大鼠的假手术组。分组后即开始给药,1次/d,共4周,末次给药12 h后,采用改良神经功能评分(mNSS)法进行神经缺损评分;采用TTC染色法检测脑梗死面积;HE、Nissl染色进行神经元细胞及尼氏小体形态学观察;Tunel法进行神经元细胞凋亡检测;Elisa法检测脑组织cAMP、脑源性神经营养因子(BDNF)、神经生长因子(NGF)含量;免疫荧光法检测脑组织环磷酸腺苷(cAMP)、p-PKA、p-CREB阳性细胞数及其蛋白共表达阳性细胞数;Western blot法检测脑组织PKA、p-PKA、CREB、p-CREB蛋白表达量。结果:模型组大鼠比较假手术组大鼠的mNSS评分、脑梗死面积百分比显著增加(均P<0.05),HE染色和Nissl染色可见明显的神经元细胞损伤和尼氏小体破坏,脑组织cAMP、BDNF、NGF含量和PKA、p-PKA、CREB、p-CREB蛋白表达量显著下降,模型组大鼠比较假手术组大鼠的cAMP、p-PKA、p-CREB阳性细胞数和蛋白共表达阳性细胞数也明显下降(均P<0.05)。与模型组比较,丙泊酚给药组大鼠mNSS评分、脑梗死面积百分比显著降低(均P<0.05),HE染色和Nissl染色可见神经元细胞损伤和尼氏小体破坏有不同程度改善,脑组织cAMP、BDNF、NGF含量和PKA、p-PKA、CREB、p-CREB蛋白表达量显著升高(均P<0.05),cAMP、p-PKA、p-CREB阳性细胞数及其蛋白共表达阳性细胞数均显著升高(均P<0.05)。结论:丙泊酚可能通过cAMP/PKA/CREB通路改善CIRI大鼠神经功能。

电针对局灶性脑缺血大鼠JAK2/STAT3通路、血管内皮生长因子的影响及其对神经保护作用机制的研究

目的观察电针“百会”“大椎”对局灶性脑缺血大鼠酪氨酸蛋白激酶2/信号转导和转录激活因子3(Janus kinase 2/signal transducer and activator of transcription 3,JAK2/STAT3)通路和血管内皮生长因子(vascular endothelial growth factor,VEGF)的影响,探讨电针对局灶性脑缺血大鼠神经保护的作用机制。方法将36只SD大鼠随机分为正常组、假手术组、模型组、电针组,每组9只,采用Longa线栓法进行局灶性脑缺血模型复制,电针组模型复制4 h后予以电针治疗,共治疗7 d。比较各组大鼠模型复制后4 h和7 d的神经功能评分;Western blot法检测各组大鼠脑组织JAK2、磷酸化酪氨酸蛋白激酶2(phosphorylated Janus kinase 2,p-JAK2)、STAT3、磷酸化信号转导和转录激活因子3(phosphorylated signal transducer and activator of transcription 3,p-STAT3)、VEGF蛋白表达水平;RT-PCR法检测各组大鼠脑组织JAK2、STAT3、VEGF mRNA表达水平。结果模型复制后4 h,电针组、模型组大鼠神经功能评分显著高于假手术组和正常组(P<0.05);与假手术组比较,模型组JAK2、p-JAK2、STAT3、p-STAT3、VEGF蛋白表达水平均显著升高(P<0.05),蛋白表达水平显著升高(P<0.05);JAK2、STAT3、VEGF mRNA表达水平显著升高(P<0.05);与模型组比较,电针组7 d后神经功能评分显著降低(P<0.05);STAT3、VEGF、p-STAT3、JAK2、p-JAK2蛋白表达水平显著升高(P<0.05);JAK2、STAT3、VEGF mRNA表达水平显著升高(P<0.05)。结论电针可能通过激活JAK2/STAT3通路、促进下游VEGF的表达发挥对局灶性脑缺血大鼠的神经保护作用。

+Gx水平加速度重复作用对黏着斑相关蛋白表达水平的影响

背景航空医学研究发现正加速度(+Gx)重复作用可能导致肺损伤,损伤机制尚不明确。目的研究+Gx重复暴露后,兔黏着斑相关蛋白表达水平的变化,探索+Gx致肺损伤的作用机制。方法新西兰大白兔32只,随机分为对照组和实验组,实验组按实验天数分为10 d组、20 d组和30 d组,每组8只。实验组采用水平加速度试验平台加载+Gx加速度,加速度稳定峰值4 G,峰值持续时间2 s,间隔5 min,20次/d。对照组不给予加速度作用,其他处理同实验组。造模结束后处死动物,留取肺组织标本做免疫荧光和Western blot分析,检测Src、FAK和Paxillin蛋白的变化。结果免疫荧光结果显示,相比对照组,实验组Src、FAK和Paxillin蛋白表达比例均有一定升高,且3种蛋白的相对荧光强度在实验组中随着实验天数的增加而上升;Western blot结果显示,重复+Gx加速度作用使兔黏着斑相关蛋白FAK、Src和Paxillin均升高(P<0.05),其中FAK蛋白表达量会随着重复次数的增加而增大,Src和Paxillin蛋白在暴露20 d后趋于稳定状态。结论+Gx加速度作用下兔肺组织中的黏着斑相关蛋白表达水平升高,且随作用天数增加,不同蛋白表达特点不同。

老年急性心肌梗死患者黏着斑激酶和脂肪酸结合蛋白4与心肌损伤及心功能的关系

目的 探讨老年急性心肌梗死患者血清黏着斑激酶(FAK)和脂肪酸结合蛋白4(FABP4)水平变化与心肌损伤及心功能的关系。方法 选择2020年1月至2023年4月牡丹江心血管病医院收治的211例急性心肌梗死患者作为疾病组;选择同期在我院行体检的60例健康志愿者为对照组。比较2组血清FAK和FABP4水平,多因素logistic回归分析老年急性心肌梗死的影响因素,应用ROC曲线评估血清FAK和FABP4对老年急性心肌梗死的预测价值,Pearson相关分析血清FAK和FABP4与心肌损伤和心功能的相关性。结果 疾病组患者血清FAK、FABP4、肌酸激酶同工酶(CK-MB)、肌钙蛋白I(cTnI)、肌酸激酶(CK)、左心室收缩末期内径(LVESD)和左心室舒张末期内径(LVEDD)显著高于对照组,左心室射血分数(LVEF)显著低于对照组,差异有统计学意义(P<0.05,P<0.01)。血清FAK和FABP4与CK-MB、cTnI、CK、LVESD和LVEDD均呈正相关,与LVEF呈负相关(P<0.05)。多因素logistic回归分析显示,血清FAK(OR=2.872,95%CI:2.230~3.698,P=0.000)和FABP4(OR=2.667,95%CI:1.713~4.154,P=0.000)是老年急性心肌梗死发生的影响因素。ROC曲线分析显示,血清FAK诊断的临界值为25.60μg/L,曲线下面积为0.801(95%CI:0.750~0.852);血清FABP4诊断的临界值为23.22μg/L,曲线下面积为0.760(95%CI:0.707~0.812);FAK和FABP4联合分析显示,曲线下面积为0.899(95%CI:0.839~0.918)。结论 老年急性心肌梗死患者血清FAK和FABP4异常高表达,与心肌损伤及心功能密切相关,单独或联合分析可有效预测急性心肌梗死的发生。

Degradation of FAK-targeting by proteolytic targeting chimera technology to inhibit the metastasis of hepatocellular carcinoma

Liver cancer is a prevalent malignant cancer,ranking third in terms of mortality rate.Metastasis and recurrence primarily contribute to the high mortality rate of liver cancer.Hepatocellular carcinoma(HCC)has low expression of focal adhesion kinase(FAK),which increases the risk of metastasis and recurrence.Nevertheless,the efficacy of FAK phosphorylation inhibitors is currently limited.Thus,investigating the mechanisms by which FAK affects HCC metastasis to develop targeted therapies for FAK may present a novel strategy to inhibit HCC metastasis.This study examined the correlation between FAK expression and the prognosis of HCC.Additionally,we explored the impact of FAK degradation on HCC metastasis through wound healing experiments,transwell invasion experiments,and a xenograft tumor model.The expression of proteins related to epithelial-mesenchymal transition(EMT)was measured to elucidate the underlying mechanisms.The results showed that FAK PROTAC can degrade FAK,inhibit the migration and invasion of HCC cells in vitro,and notably decrease the lung metastasis of HCC in vivo.Increased expression of E-cadherin and decreased expression of vimentin indicated that EMT was inhibited.Consequently,degradation of FAK through FAK PROTAC effectively suppressed liver cancer metastasis,holding significant clinical implications for treating liver cancer and developing innovative anti-neoplastic drugs.

乙肝肝纤维化患者肝组织黏着斑激酶、蛋白激酶B的表达及意义

目的:探讨乙肝肝纤维化患者肝组织黏着斑激酶(FAK)、蛋白激酶B(AKT)的表达及其意义。方法:纳入75例行肝脏穿刺的慢性乙肝患者作为研究对象,根据纤维化程度(HE和Masson染色)将其分为A组(S0-S1级,n=26)、B组(S2级,n=27)、C组(S3-S4级,n=22)。收集并比较各组患者性别、年龄、总胆红素(TBIL)、肝脏弹性硬度(LSM)、丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)等一般资料。应用S-P免疫组织化学、Western blot、实时荧光定量PCR检测并比较各组FAK、AKT蛋白及基因水平。结果:各组患者性别、TBIL差异均无统计学意义(P>0.05);各组年龄、LSM、ALT、AST比较,差异均有统计学意义(P<0.05)。免疫组化结果显示,各组患者肝组织中FAK、AKT蛋白阳性表达积分比较:A组<B组<C组(P<0.05),各组p-AKT蛋白表达积分比较:A组>B组>C组(P<0.05)。Western blot结果显示,各组肝组织中FAK、AKT蛋白相对表达水平比较:A组<B组<C组(P<0.05),各组p-FAK、p-AKT蛋白相对表达水平比较:A组>B组>C组(P<0.05)。实时荧光定量PCR结果显示,各组肝组织中FAK、AKT基因mRNA相对表达水平比较:A组<B组<C组(P<0.05)。结论:FAK、AKT表达水平与乙肝患者肝纤维化的发生及肝纤维化程度密切相关。

根皮素通过抑制FAK改善肾小管间质纤维化

目的探究根皮素能否通过抑制黏着斑激酶(FAK)改善肾小管间质纤维化。方法肾小管上皮细胞NRK-52E经TGF-β1(10 ng/mL)诱导建立肾纤维化细胞模型,并构建单侧输尿管梗阻(UUO)肾间质纤维化小鼠模型。通过免疫荧光及Western blot法检测细胞及小鼠肾脏组织中α-SMA、FN的蛋白表达水平,明确根皮素体内外抗肾纤维化作用;检测实验小鼠血清中肌酐(Cr)和尿素氮(BUN)水平,分析根皮素的肾保护作用;以苏木精-伊红(HE)染色和Masson染色观察根皮素对UUO小鼠肾脏病理学改变和胶原纤维沉积的影响;Western blot检测TGF-β1诱导的NRK-52E细胞和UUO小鼠肾组织中FAK、p-FAK的蛋白表达水平;通过分子对接预测根皮素与FAK蛋白的潜在结合模式和结合能力;使用FAK抑制剂PND-1186,探究根皮素改善肾间质纤维化的作用机制。结果根皮素可逆转TGF-β1所致的肾小管上皮细胞及UUO小鼠肾组织中α-SMA、FN的蛋白表达水平升高,且显著降低UUO小鼠血清中Cr、BUN水平,改善UUO小鼠肾小管扩张、炎性细胞浸润及间质胶原沉积;根皮素可以显著抑制UUO小鼠肾组织中FAK、p-FAK蛋白的表达水平,分子对接提示根皮素与FAK蛋白之间具有良好相互作用。根皮素与PND-1186均可改善TGF-β1诱导的NRK-52E细胞纤维化。结论根皮素通过抑制FAK信号通路在体内外发挥抗肾间质纤维化作用。

通关藤对胃癌小鼠Src/FAK信号通路及Th1/Th2相关因子水平的影响

目的探讨通关藤对胃癌小鼠类固醇受体共激活因子(Steroid receptor coactivator,Src)/黏着斑激酶(Focaladhesion kinase,FAK)信号通路及Th1/Th2相关因子水平的影响。方法将SPF级成年雌雄各半C57BL/6小鼠60只,根据随机数字表法分为空白对照组、模型组(注射生理盐水)、环磷酰胺组(注射环磷酰胺)、通关藤低、中、高剂量组(分别注射0.1 ml、0.2 ml、0.4 ml通关藤注射液),每组各10只。干预1次/2 d,于干预第21天时处死所有小鼠,颈部取血。测量小鼠体质量以及胸腺、脾、肿瘤质量。HE染色观察小鼠瘤体病理形态变化。流式细胞术检测小鼠CD4^(+)、CD8^(+)以及CD4^(+)/CD8^(+)水平,ELISA法检测白细胞介素-2(Interleukin-2,IL-2)、白细胞介素-4(Interleukin-4,IL-4)、白细胞介素-10(Interleukin-10,IL-10)、干扰素-γ(Interferon-γ,INF-γ)水平,Western blot法检测Src、磷酸化Src(p-Src)、FAK、磷酸化FAK(p-FAK)蛋白表达水平。结果与模型组比较,通关藤各干预组脾指数、胸腺指数水平升高,且随通关藤剂量增加,脾指数、胸腺指数水平、抑瘤率均升高,差异有统计学意义(P<0.05)。环磷酰胺组脾指数和胸腺指数明显低于各通关藤剂量组,差异有统计学意义(P<0.05);环磷酰胺组和通关藤高剂量组抑瘤率明显高于通关藤低、中剂量组,差异有统计学意义(P<0.05)。HE染色结果显示,模型组肿瘤细胞排列整齐且密集,而环磷酰胺组和通关藤各剂量组肿瘤细胞密度有所减少,且分布不均,并呈不同程度的肿瘤细胞坏死灶。与模型组比较,通关藤各干预组IL-2、INF-γ水平升高,IL-4、IL-10水平降低,差异有统计学意义(P<0.05);相较于环磷酰胺组,通关藤低、中、高剂量组IL-2、INF-γ水平升高,IL-4、IL-10水平降低,差异有统计学意义(P<0.05),且通关藤干预剂量越高,IL-2、INF-γ水平升高越明显,IL-4、IL-10水平降低越明显(P<0.05)。与模型组比较,环磷酰胺组和通关藤各干预组CD4^(+)、CD4^(+)/CD8^(+)水平升高,CD8^(+)水平降低,差异有统计学意义(P<0.05);与环磷酰胺组比较,通关藤低、中、高剂量组CD4^(+)、CD4^(+)/CD8^(+)水平升高,CD8^(+)水平降低,差异有统计学意义(P<0.05),且通关藤干预剂量越高,CD4^(+)、CD4^(+)/CD8^(+)水平升高越明显,CD8^(+)水平降低越明显(P<0.05)。与模型组比较,环磷酰胺组和通关藤各干预组p-Src/Src、p-FAK/FAK蛋白水平降低,差异有统计学意义(P<0.05);与环磷酰胺组比较,通关藤低、中、高剂量组p-Src/Src、p-FAK/FAK蛋白水平升高,差异有统计学意义(P<0.05),且通关藤干预剂量越高,p-Src/Src、p-FAK/FAK蛋白水平降低越明显。结论通关藤可调节胃癌小鼠Src/FAK信号通路及Th1/Th2相关因子水平,从而发挥抑癌作用,且剂量越高,效果越显著。

TFAP2A对肾小球硬化相关基因ADCK4转录调控机制的研究

目的探索细胞中TFAP2A对局灶节段性肾小球硬化(FSGS)相关基因含aarF结构域的激酶4(ADCK4)的转录调控机制及TFAP2A与ADCK4是否存在特定的结合区域。方法生物信息学分析肾小球硬化基因火山图,ADCK4及TFAP2A表达水平的关系。JASPAR数据库预测ADCK4基因转录起始位点-464 bp/+206 bp区域包含TFAP2A转录因子结合位点;TFAP2A siRNA浓度分别为5、10、15µmol/L,TFAP2A过表达质粒质量浓度分别为50、100、300µg/L,通过双萤光素酶报告基因实验验证TFAP2A对ADCK4基因启动子水平的调控作用。TFAP2A siRNA及TFAP2A过表达质粒转染细胞,实时荧光定量PCR检测TFAP2A、ADCK4 mRNA表达,蛋白免疫印迹实验检测TFAP2A、ADCK4蛋白表达。染色质免疫沉淀试验验证TFAP2A与ADCK4启动子的特定区域结合。结果生物信息学分析显示FSGS肾组织中RNA-Seq RNA表达上调的基因273个,表达下调的基因219个;ADCK4与TFAP2A表达水平呈正相关(P<0.01)。双萤光素酶报告基因实验证明TFAP2A siRNA浓度为10、15µmol/L的ADCK4启动子相对萤光素酶活性增强,TFAP2A过表达质粒质量浓度为100、300µg/L的ADCK4启动子萤光素酶活性降低(P<0.05)。与对照组相比,实验组ADCK4 mRNA和蛋白表达水平升高;过表达实验中,与对照组比较,实验组ADCK4 mRNA和蛋白表达水平降低(P<0.05)。染色质免疫沉淀试验发现TFAP2A能与ADCK4启动子的特定区域结合。结论转录因子TFAP2A负向调控ADCK4基因表达,增加了调控足细胞重要基因的转录因子成员。

Focal adhesion kinase signaling is necessary for the hydrogen sulfide-enhanced proliferation,migration,and invasion of HTR8/SVneo human trophoblasts

Objective:Hydrogen sulfide(H_(2)S)has been elucidated that it promotes migration and invasion in human placenta trophoblasts.However,the signaling pathway underlying H_(2)S-based regulation of trophoblasts remains unknown.Hence,we investigated the potential effect of sodium hydrosulfide(NaHS),an exogenous H_(2)S donor,on extravillous trophoblasts.Methods:The Cell Counting Kit-8 was used to detect the proliferative activity of trophoblasts and to screen the optimal concentration of NaHS.The migration and invasion of HTR8/SVneo cells were measured by Transwell assays.Gene expression was determined by quantitative real-time PCR analysis.Protein expression was determined by western blot.Results:We found that NaHS could promote the proliferation,migration,and invasion of HTR8/SVneo cells.The phosphorylation of focal adhesion kinase(FAK),Src,and extracellular signal-regulated kinase(ERK)were activated by NaHS.Moreover,NaHS also upregulated the expression of matrix metalloproteinase-2(MMP-2)and MMP-9,downregulated the expression of E-cadherin in HTR8/SVneo cells.The application of NaHS could increase the expression of cystathionine-β-synthase.Conclusion:Both FAK-Src signaling and the upstream signaling cascade of ERK activation play a significant important role in NaHS-induced proliferation,migration,and invasion via upregulating activity of MMP-2,MMP-9,and downregulating E-cadherin in HTR8/SVneo cells.These novel findings may provide a strong foundation for the clinical application of H_(2)S donor drugs.

Electroacupuncture preconditioning protects against focal cerebral ischemia/reperfusion injury via suppression of dynamin-related protein 1

Electroacupuncture preconditioning at acupoint Baihui （GV20） can reduce focal cerebral ischemia/reperfusion injury. However, the precise protective mechanism remains unknown. Mitochondrial fission mediated by dynamin-related protein 1 （Drp1） can trigger neuronal apoptosis following cerebral ischemia/reperfusion injury. Herein, we examined the hypothesis that electroacupuncture pretreatment can regulate Drp1, and thus inhibit mitochondrial fission to provide cerebral protection. Rat models of focal cerebral ischemia/reperfusion injury were established by middle cerebral artery occlusion at 24 hours after 5 consecutive days of preconditioning with electroacupuncture at GV20 （depth 2 mm, intensity 1 mA, frequency 2/15 Hz, for 30 minutes, once a day）. Neurological function was assessed using the Longa neurological deficit score. Pathological changes in the ischemic penumbra on the injury side were assessed by hematoxylin-eosin staining. Cellular apoptosis in the ischemic penumbra on the injury side was assessed by terminal deoxyribonucleotidyl transferase-mediated dUTP-digoxigenin nick end labeling staining. Mitochondrial ultrastructure in the ischemic penumbra on the injury side was assessed by transmission electron microscopy. Drp1 and cytochrome c expression in the ischemic penumbra on the injury side were assessed by western blot assay. Results showed that electroacupuncture preconditioning decreased expression of total and mitochondrial Drp1, decreased expression of total and cytosolic cytochrome c, maintained mitochondrial morphology and reduced the proportion of apoptotic cells in the ischemic penumbra on the injury side, with associated improvements in neurological function. These data suggest that electroacupuncture preconditioning-induced neuronal protection involves inhibition of the expression and translocation of Drp1.