HMGB1对宫颈癌HeLa细胞凋亡的影响及其作用机制

目的 观察HMGB1对人宫颈癌HeLa细胞生长及凋亡的影响并研究其可能的作用机制.方法 构建HMGB1高表达质粒和RNA干扰质粒,将HMGB1高表达质粒与RNA干扰质粒分别转染到HeLa细胞中,采用MTT实验、PI单染流式细胞术和Annexin V-PI双标法流式细胞术检测HeLa细胞的增殖活性、细胞周期和凋亡情况.采用RT-PCR和western blot法检测HMGB1基因沉默对Caspase-3、bcl-2 和细胞色素C表达的影响.结果 HMGB1高表达载体(pEGFP-N1-HMGB1)与阴性对照质粒分别转染到HeLa细胞,RT-PCR和Western blot结果显示HMGB1重组质粒转染HeLa后可明显增加HMGB1的mRNA 及蛋白表达(P＜0.05).HMGB1干扰病毒载体(HMGB1 SiRNA)与空白病毒载体分别转染到HeLa细胞中,RT-PCR和Western blot结果显示HMGB1 SiRNA转染HeLa后可明显抑制HMGB1的mRNA及蛋白表达(P＜0.05).MTT法检测HMGB1高表达及基因沉默后HeLa的细胞生长曲线,结果显示HMGB1高表达可明显提高HeLa的细胞生长速度(P＜0.05),HMGB1沉默后HeLa的细胞生长明显受到抑制(P＜0.05).PI 染色流式细胞仪结果显示:HMGB1过表达后,细胞正常增殖周期被加速(P＜0.05);HMGB1沉默后,细胞增殖周期被抑制(P＜0.05).Annexin V-PI双标法流式细胞仪结果显示,HMGB1过表达后,HeLa细胞凋亡率明显下降(P＜0.05);HMGB1沉默后,HeLa细胞凋亡率明显上升(P＜0.05).RT-PCR方法检测不同细胞组Caspase-3和bcl-2 mRNA的表达,结果显示:HMGB1基因沉默后,Caspase-3 mRNA的表达明显增加(P＜0.05),bcl-2 mRNA的表达明显减少(P＜0.05).Western blot结果显示:HMGB1 基因沉默后,细胞色素C和Caspase-3蛋白表达水平增加,bcl-2蛋白表达水平减少(P＜0.05).结论 HMGB1可提高HeLa细胞生长速度、增殖周期,抑制HeLa细胞凋亡.HMGB1基因沉默可抑制Hela细胞增殖,促进其凋亡.影响Caspase-3—细胞色素C途径及调节bcl-2的表达可能是其主要作用机制.     

携带IL-2和IL-12基因的痘苗病毒可以诱导无毒性抗肿瘤应答

为了明确在肿瘤疫苗免疫的局部应用白细胞介素 ( IL) 2和 IL- 1 2的效果 ,作者将编码鼠 IL - 2和 IL - 1 2基因及实验肿瘤抗原基因 ( Lac Z)一起插入痘苗病毒构建成携带L ac Z基因、gpt报告基因、IL- 2基因和 IL- 1 2两个亚基 ( p35和 p40 )基因的肿瘤疫苗 ,并对其治疗效果进行研究。　　具体方法 :用携带 IL- 1 2两个亚基 ( p35和 p40 )基因的 p TK0 334质粒与表达 L ac Z的重组病毒 ( VZV)同源重组产生表达 IL- 1 2和 Lac Z的重组病毒 ( VAC- 1 2 ) ;p TK0 334质粒与表达 IL- 2和 Lac Z的重组病毒 ( VAC- 2 )同源重组产…     

微小 RNA-338-3p靶向调控高迁移率族蛋白 B1增强子宫内膜癌对紫杉醇敏感性的研究

目的 探讨miR-338-3p靶向调控高迁移率族蛋白B1(HMGB1)影响子宫内膜癌对紫杉醇(Paclitaxel,PTX)敏感性的分子机制.方法 实时荧光定量聚合酶链反应(qRT-PCR)和蛋白印迹法(Western blottingting)检测miR-338-3p和HMGB1在子宫内膜癌细胞Ishikawa和HEC-1B中的表达;双荧光素酶报告基因实验验证miR-338-3p和HMGB1之间的靶向关系;将Ishikawa和HEC-1B细胞分为如下5组:miR-338-3p组(转染miR-338-3p mimics组)、miR-NC组(转染miRNA阴性对照组)、si-HMGB1组(转染干扰RNA)、si-NC组(转染siRNA阴性对照)、miR-338-3p+HMGB1组(共转染miR-338-3pmimics和pcDNA3.0 HMGB1组).将各组用转染试剂转染至细胞,用不同浓度的PTX处理上述转染组细胞,CCK-8法检测Ishikawa和HEC-1B细胞增殖,Annexin V-FITC/PI检测细胞凋亡,Western blotting检测HMGBI蛋白表达.结果 与人正常子宫内膜上皮细胞ESC相比,miR-338-3p在子宫内膜癌细胞Ishikawa和HEC-1B中表达下调[(1.00±0.10)比(0.51±0.04)、(0.46±0.04)],而HMGB1则相反;miR-338-3p靶向并负性调节HMGB1表达;过表达miR-338-3p抑制子宫内膜癌细胞Ishikawa和HEC-1B增殖,促进凋亡,增加其对PTX敏感,与敲低HMGB1结果一致;HMGB1可部分逆转miR-338-3p对子宫内膜癌细胞增殖,凋亡以及对PTX敏感性的影响.结论 miR-338-3p通过负性调控HMGB1抑制子宫内膜癌细胞Ishikawa和HEC-1B增殖,促进凋亡和增强其对PTX敏感性.     

RNAi抑制胰腺癌PANC-1细胞MMP-2mRNA的表达

目的 观察RNAi体外沉默基质金属蛋白酶2(MMP-2)基因对胰腺癌PANC-1细胞MMP-2 mRNA表达的抑制作用.方法 设计靶向MMP-2的siRNA,并构建到pGCsi-U6质粒,重组质粒脂质体法转染PANC-1细胞;流式细胞术检测细胞GFP表达率,RQ-PCR检测细胞MMP-2的mRNA表达水平.结果 PCR鉴定证实重组质粒构建成功,质粒转染细胞GFP表达率最高达82.1%.转染干扰质粒的PANC-1细胞MMP-2基因mRNA表达抑制了71.74%(P＜0.05).结论 RNAi明显抑制胰腺癌PANC-1细胞MMP-2 mRNA的表达,可望RNAi能为胰腺癌治疗开辟新的思路.     

重组CEA和IL-2抗肿瘤基因疫苗的构建及其抗肿瘤作用研究

目的成功构建重细CEA、CEA／IL-2抗肿瘤基因疫苗,并检测其激活的淋巴细胞对肿瘤细胞的杀伤作用。方法将CEA、CEA／IL-2基因导入真核表达质粒pcDNA3．1,并转染入DC细胞,通过转染DC细胞活化淋巴细胞,将活化的淋巴细胞与人CEA＋肝癌细胞共培养,检测其对肿瘤细胞的杀伤作用。结果重组CEA、CEA／IL-2组均检测出较强的抗肿瘤效应,且重组CEA／IL-2组与重组CEA组差异具有统计学意义（P〈0．05）。结论联合CEA／IL-2基因疫苗具有抗肿瘤作用,且其抗肿瘤作用明显优于单基因CEA基因疫苗,证实了重组肿瘤基因疫苗对肿瘤细胞的杀伤作用。     

细胞信号转导抑制因子1沉默增强人口腔癌细胞对化疗药物的敏感性

目的 研究细胞因子信号转导抑制因子1(SOCS1)基因沉默对人口腔癌细胞化疗药物敏感性的影响及相关机制。方法 Western blotting及实时定量PCR验证SOCS1干扰序列沉默人口腔癌KB细胞株中SOCS1的表达水平；MTT法分析细胞对化疗药物敏感性的变化；流式细胞术检测细胞凋亡。结果 将SOCS1干扰片段转染KB细胞后,SOCS1 mRNA及蛋白表达水平均明显降低。沉默SOCS1表达后,化疗药物5-氟尿嘧啶和长春新碱对KB细胞的半数抑制浓度(IC50)均显著变小(P<0.05),SOCS1沉默还可增加长春新碱诱导的细胞凋亡(P<0.05),SOCS1表达抑制后KB细胞NF-κB和Caspase-3的蛋白表达水平明显降低,与对照组比较差异均有统计学意义(P<0.05)；结论 SOCS1表达有效抑制后,人口腔癌细胞KB对化疗药物的敏感性增强,且促进化疗药物诱导的肿瘤细胞凋亡。     

HMGB1基因对高糖诱导的血管内皮细胞损伤的影响

目的:探讨高迁移率族蛋白B1(HMGB1)基因对高糖诱导的血管内皮细胞损伤的影响及作用机制.方法:培养人血管内皮细胞,实验分为NG组(5.5 mmol/L葡萄糖处理)、HG组(33.3 mmol/L葡萄糖处理)、HG+ si-NC组(转染siRNA阴性对照及33.3 mmol/L葡萄糖处理)和HG+ si-HMGB1组(转染HMGB1 siRNA及33.3 mmol/L葡萄糖处理).比较各组细胞HMGB1、p65和IκB-α蛋白表达,细胞活力、氧化应激及炎症反应水平差异.结果:与NG组比,HG组HMGB1 mRNA和蛋白表达升高,细胞活力降低,LDH和ROS升高,SOD降低,ICAM-1、MCP-1和IL-6水平升高,p65表达上调,IKB-α表达下调(P＜0.05).与HG+ si-NC组比,HG+ si-HMGB1组HMGB1 mRNA和蛋白的表达降低,细胞活力升高,LDH和ROS降低,SOD升高,ICAM-1、MCP-1和IL-6降低,p65表达下调,IκB-α表达上调(P＜0.05).结论:抑制HMGB1表达能提高血管内皮细胞的活力,减轻氧化损伤及炎症反应,其作用机制可能与抑制NF-κB信号通路的激活有关.     

转染IL-6基因增强MCF-7人乳腺癌细胞肿瘤相关抗原的表达

目的 研究IL-6 影响癌症预后的机制和IL-6与乳腺癌肿瘤相关抗原CA15-3, CEA 和CA125 的关系.方法 转染外源IL-6基因到MCF-7细胞株, 用酶联免疫吸附法(ELISA) 定量培养液中细胞分泌的CA15-3, CEA和CA125.结果 在 72 h 培养后, 成功转染pCI-neo-IL-6质粒的MCF-7细胞分泌IL-6 (338.5±22.6) pg/106细胞明显高于没有转染的细胞(25.4±4.6) pg/106细胞 (P＜0.01) 和无IL-6基因的质粒pCI-neo转染的细胞(19.6±3.0) pg/106细胞 (P＜0.01).pCI-neo-IL-6转染的MCF-7细胞分泌CA15-3, CEA 和CA125同样明显高于没有转染的细胞和空载体pCI-neo转染的MCF-7细胞.特异性IL-6抗体降低CA15-3, CEA 和CA125在MCF-7细胞和IL-6 cDNA转染的MCF-7细胞中表达.结论 转染IL-6基因可增强人乳腺癌细胞肿瘤相关抗原的表达,高IL-6血症的乳腺癌病人预后不良部分原因可能是高IL-6刺激癌细胞表达肿瘤相关抗原.     

脂质体介导乙型肝炎病毒核心抗原基因转染人树突状细胞的效率

目的 观察脂质体介导HBcAg基因转染来源于人外周血单个核细胞(PBMC)树突状细胞(DC)的转染效率.方法 用HES离心沉淀法分离人外周血PBMC,经粒-巨细胞集落刺激因子(GM-CSF)、白细胞介素-4(IL-4)诱导培养DC,培养第5天以阳离子脂质体为载体将报告基因GFP(DNA:脂质体比例为1:3、1:4、1:5、1:6)及HBcAg基因(DNA:脂质体1:5)导入DC,于72h经流式细胞仪检测绿色荧光蛋白(GFP)的表达率,于48、72、96、120h流式细胞仪检测HBcAg的表达率.将基因转染后的DC 与自体淋巴细胞混合培养,检测其细胞内γ干扰素(IFN-γ)、IL-4表达水平.结果 倒置显微镜下观察脂质体转染后DC的的形态无明显变化.报告基因GFP与脂质体比例不同,其转染效率有差异,72h的表达率为37.12%(1:3)、48.55%(1:4)、52.13%(1:5)、50.75%(1:6).HBcAg基因转染DC后48、72、96、120h的HBcAg表达率分别为31.58%、55.80%、54.18%、56.99%.转染后DC与自体淋巴细胞混合培养后,淋巴细胞高表达IFN-γ,较少表达IL-4,呈现Th1为优势的免疫应答.结论 应用阳离子脂质体能有效的将HBcAg基因转染到人PBMC来源的DC,转染72h后抗原表达稳定;转染HBcAg基因的DC仍以诱导Th1免疫应答反应为主.     

干扰素诱导的双链RNA依赖性蛋白激酶体外抗乙型肝炎病毒活性的研究

目的构建表达双链RNA依赖性蛋白激酶(PKR)融合绿色增强荧光蛋白(p EGFP-PKR)真核表达质粒,并进一步研究PKR蛋白在体外抗乙型肝炎病毒(HBV)活性。方法以p EGFP-N1为空载体,运用分子克隆技术构建重组质粒p EGFP-PKR,通过双酶切和直接测序两种方法验证重组质粒p EGFP-PKR是否构建成功。以能分泌完整HBV病毒颗粒子的肝胚瘤细胞株Hep G2.2.15细胞为细胞模型,采用重组质粒转染方式处理Hep G2.2.15细胞,运用荧光显微镜观察融合蛋白p EGFP-PKR在细胞内的表达,以电化学发光方法和实时荧光定量PCR技术分析细胞上清HBV抗原表达和细胞病毒复制水平。结果酶切鉴定和序列分析证实成功构建重组质粒p EGFP-PKR,转染Hep G2.2.15细胞后在荧光显微镜下可见融合蛋白p EGFP-PKR表达,同时细胞分泌的HBV抗原与空载体组相比较明显下降(P<0.05),而细胞外HBV复制水平未见明显变化。结论在体外肝细胞模型中,PKR蛋白具有一定的抗HBV活性作用。     

Preconditioning of physiological cyclic stretch attenuated HMGB1 expression in pathologically mechanical stretch-activated A549 cells and ventilator-induced lung injury rats through inhibition of IL-6/STAT3/SOCS3

Previous studies have shown that physiologically cyclic stretch (5% CS) attenuated both oxidative- and LPS-induced increases in HMGB1 expression via STAT3. However, little information exists about the effect of precondition of physiological cyclic stretch (CS) on the expression of HMGB 1, which play a crucial role in ventilator-induced lung injury (VILI). We found that 5% CS-preconditioning significantly inhibited HMGB 1 expression, but not HMGB 1 receptors. 5% CS-preconditioning inhibits the IL-6/STAT3 pathway, and the inhibitory effect on the expression of HMGB 1 induced by 5% CS-preconditioning is abolished by additional treatment of rmIL-6. 5% CS-preconditioning also induces SOCS3 upregulation, and 5% CS-preconditioning fails to inhibit the IL-6/STAT3 pathway in cells transfected with SOCS3 siRNA. Moreover, low tidal volume ventilation preconditioning also decreases the severity of VILI evidenced by the markedly improved pulmonary alveolar-capillary barrier dysfunction, wet/dry weight ratio, and histological analysis. These results suggest that preconditioning of physiological 5% CS can reduce the expression of HMGB 1 induced by pathologically mechanical stretch through IL-6/STAT3 pathway associated with up-regulated SOCS3 expression.     

微小 RNA-216b-5p对骨肉瘤 MG63细胞功能的影响及其与高迁移率族蛋白 B1的靶向关系

目的 探讨微小RNA-216b-5p(miR-216b-5p)对骨肉瘤MG63细胞增殖、侵袭和凋亡的影响及其与高迁移率族蛋白B1(HMGB1)的靶向关系.方法 将体外培养的MG63细胞分为mimics-NC组、miR-216b-5p mimics组、inhibitor-NC组和miR-216b-5p inhibitor组,采用实时荧光定量PCR检测miR-216b-5p的表达,MTT法、Transwell小室和流式细胞仪分别检测细胞增殖、侵袭和凋亡能力.采用双荧光素酶报告基因实验检测miR-216b-5p和HMGB1的靶向关系,蛋白质印迹法(Western blot-ting)检测HMGB1蛋白的表达.结果 与mimics-NC组相比,miR-216b-5p mimics组细胞中miR-216b-5p的表达水平[(5.36±0.54)比(1.00±0.11)]和细胞凋亡率[(20.36±3.15)％比(8.58±1.22)％]明显升高,而细胞增殖活力、侵袭能力和细胞中HMGB1蛋白的表达水平均明显降低(P<0.05);miR-216b-5p inhibitor组细胞中miR-216b-5p的表达水平[(0.24±0.03)比(0.96±0.08)]和细胞凋亡率[(2.05±0.38)比(9.27±1.16)]较inhibitor-NC组明显降低,而细胞增殖活力、侵袭能力和HMGB1蛋白的表达水平较inhibitor-NC组均明显升高(P<0.05).双荧光素酶报告基因实验证实HMGB1是miR-216b-5p的靶基因.结论 miR-216b-5p可能通过靶向调控HMGB1表达,抑制骨肉瘤MG63细胞增殖、侵袭并诱导细胞凋亡.     

Cannabinoid receptor 2 promotes the intracellular degradation of HMGB1 via the autophagy-lysosome pathway in macrophage

High mobility group box 1 (HMGB1) is a late phase inflammatory mediator in many inflammatory diseases. Extracellular HMGB1 could bind to many membrane receptors to activate downstream signaling molecules and promote inflammation resulting in cell and tissue damage. In our previous work, we found cannabinoid receptor Ⅱ(CB2R) inhibited the expression of HMGB1 in lipopolysaccharide (LPS)-induced septic models in vivo and in vitro, but the underlying mechanism is still unclear. The present study was aimed to explore the possible pathway through which CB2R suppressed HMGB1. Here, we found that the specific agonist of CB2R, GW405833 (GW) could induce intracellular HMGB1 degradation without influencing HMGB1 mRNA in peritoneal macrophages. Then we observed that autophagy inhibitor 3-methyladenine (3-MA) but not proteasome inhibitor MG-132 (MG) could block GW-induced HMGB1 degradation, which indicated that the autophagy-lysosome but not the ubiquitination pathway was involved in this process. Further study showed that GW could promote the integrity of autophagy flux in macrophages in terms of increased level of LC3Ⅱand decreased expression of p62 protein. It also observed that inhibition of autophagy blocked GW-induced nuclear translocation of HMGB1 in macrophages. GW could up-regulate expression of Cathepsin B (CTSB), and inhibition of CTSB blocked GW-induced HMGB1 degradation. In summary, all the data showed that activation of CB2R could promote the intracellular degradation of HMGB1 via the autophagy-lysosome pathway in macrophage.     

β1-Adrenergic receptor-mediated HO-1 induction, via PI3K and p38 MAPK, by isoproterenol in RAW 264.7 cells leads to inhibition of HMGB1 release in LPS-activated RAW 264.7 cells and increases in survival rate of CLP-induced septic mice

High mobility group box (HMGB)-1 plays an important role in sepsis-associated death in experimental studies. Heme oxygenase-1 (HO-1) inducers were reported to reduce HMGB1 release in experimental sepsis. Previously, we reported on the importance of the β1-adrenergic receptor and protein kinase A pathway in the regulation of HO-1 expression by isoproterenol (ISO) in RAW 264.7 cells. We investigated whether ISO reduces HMGB1 release in LPS-activated RAW 264.7 cells and improves survival rate in septic mice due to HO-1 induction. ISO concentration-dependently increased HO-1 via Nrf-2 translocation and inhibited release of HMGB1 through the β₁-adrenergic receptor (β₁-AR) in LPS-activated RAW 264.7 cells. This conclusion was supported by the finding that dobutamine but not salbutamol increased HO-1 expression in both RAW 264.7 cells. ISO failed to inhibit HMGB1 release when HO-1 expression was suppressed by ZnPPIX, an HO-1 inhibitor in RAW 264.7 cells. ISO significantly inhibited phosphorylation of IκB-α and NF-κB-driven luciferase activity in LPS-activated RAW 264.7 cells. In addition, LY294002, a PI3K inhibitor, and SB203580, a p38 MAPK inhibitor, significantly inhibited not only HO-1 induction but also HMGB1 release by ISO. Importantly, ISO increased HO-1 protein expression in heart and lung tissues, reduced HMGB1 in plasma and increased survival rate in CLP-treated septic mice, which was significantly reversed by co-treatment with ZnPPIX. Taken together, we conclude that inhibition of HMGB1 release during sepsis via β₁-AR-mediated HO-1 induction is a novel mechanism for the beneficial effects of ISO in the treatment of sepsis.     

Salurinal抑制高迁移率族蛋白1诱导的内皮细胞凋亡研究

目的 探讨真核细胞翻译起始因子2(eIF2a)特异性抑制剂－Salurinal能否抑制高迁移率族蛋白1(HMGBl)诱导的内皮细胞凋亡及其机制.方法 应用流式细胞术(FCM)检测细胞凋亡率;采用Western-blot法检测细胞内内质网类似激酶(PERK)及eIF2a蛋白表达,比色法测定caspase-3酶活性.结果 HMGB1可呈时间和浓度依赖性的增加内皮细胞凋亡率;HMGB1呈时间和浓度依赖性地增加内皮细胞PERK蛋白表达;eIF2a特异性抑制剂Salubrinal可显著抑制HMGB1诱导的内皮细胞凋亡;Salubrinal可明显抑制HMGB1诱导的内皮细胞eIF2a蛋白磷酸化及细胞内caspase-3活性.结论 HMGB1可诱导内皮细胞凋亡,其机制与激活PERK/eIF2a/caspase-3通路有关,Salurinal可抑制HMGB1诱导的内皮细胞凋亡.     

miR-142-3p靶向HMGB1逆转乳腺癌细胞MCF-7对阿霉素的耐药性

目的化疗耐药是乳腺癌复发转移、治疗效果不理想的主要因素。本文探讨miR-142-3p通过靶向高迁移率族蛋白1(high-mobility group box 1,HMGB1)提高乳腺癌化疗敏感性的分子机制。方法实时荧光定量PCR检测人乳腺癌MCF-7细胞及阿霉素耐药株MCF-7/DOX细胞中的miR-142-3p水平;MTT法检测阿霉素(doxorubicin,DOX)处理后各组的增殖情况、流式细胞术检测凋亡率、Western blot检测HMGB1和自噬有关蛋白的表达水平;双荧光素酶报告实验评价miR-142-3p对HMGB1的靶向调控作用。结果阿霉素耐药株MCF-7/DOX细胞中的miR-142-3p水平明显下调。miR142-3p的过度表达增强了乳腺癌细胞对阿霉素的敏感性和提高阿霉素诱导的凋亡比率。HMGB1是乳腺癌细胞中miR-142-3p的直接功能靶点,HMGB1的过表达可以明显解除由miR-142-3p上调所产生的细胞凋亡和自噬抑制。结论miR-142-3p的过表达可能通过抑制自噬靶向HMGB1,增强乳腺癌细胞对阿霉素的化学敏感性。miR-142-3p/HMGB1为提高乳腺癌对药物的敏感性提供了新的靶点,具有一定价值。     

Ascorbic acid reduces HMGB1 secretion in lipopolysaccharide-activated RAW 264.7 cells and improves survival rate in septic mice by activation of Nrf2/HO-1 signals

High mobility group box 1 (HMGB1) is now recognized as a late mediator of sepsis. We tested hypothesis that ascorbic acid (AscA) induces heme oxygenase (HO)-1 which inhibits HMGB1 release in lipopolysaccharide (LPS)-stimulated cells and increases survival of septic mice. AscA increased HO-1 protein expression in a concentration- and time-dependent manner via Nrf2 activation in RAW 264.7 cells. HO-1 induction by AscA was significantly reduced by Nrf2 siRNA-transfected cells. Mutation of cysteine to serine of keap-1 proteins (C151S, C273S, and C288S) lost the ability of HO-1 induction by AscA, due to failure of translocation of Nrf-2 to nucleus. The PI3 kinase inhibitor, LY294002, inhibited HO-1 induction by AscA. Oxyhemoglobin (HbO₂), LY294002, and ZnPPIX (HO-1 enzyme inhibitor) reversed effect of AscA on HMGB1 release. Most importantly, administration of AscA (200 mg/kg, i.p.) significantly increased survival in LPS-induced endotoxemic mice. In cecal ligation and puncture (CLP)-induced septic mice, AscA reduced hepatic injury and serum HMGB1 and plasminogen activator inhibitor (PAI)-1 in a ZnPPIX-sensitive manner. In addition, AscA failed to increase survival in Nrf2 knockout mice by LPS. Thus, we concluded that high dose of AscA may be useful in the treatment of sepsis, at least, by activation of Nrf2/HO-1 signals.     

Extracellular HMGB1 as a therapeutic target in inflammatory diseases

Introduction: High-mobility group box 1 (HMGB1) is a ubiquitous nuclear protein that promotes inflammation when released extracellularly after cellular activation, stress, damage or death. HMGB1 operates as one of the most intriguing molecules in inflammatory disorders via recently elucidated signal and molecular transport mechanisms. Treatments based on antagonists specifically targeting extracellular HMGB1 have generated encouraging results in a wide number of experimental models of infectious and sterile inflammation. Clinical studies are still to come.

Areas covered: We here summarize recent advances regarding pathways for extracellular HMGB1 release, receptor usage, and functional consequences of post-translational modifications. The review also addresses results of preclinical HMGB1-targeted therapy studies in multiple inflammatory conditions and outlines the current status of emerging clinical HMGB1-specific antagonists.

Expert opinion: Blocking excessive amounts of extracellular HMGB1, particularly the disulfide isoform, offers an attractive clinical opportunity to ameliorate systemic inflammatory diseases. Therapeutic interventions to regulate intracellular HMGB1 biology must still await a deeper understanding of intracellular HMGB1 functions. Future work is needed to create more robust assays to evaluate functional bioactivity of HMGB1 antagonists. Forthcoming clinical studies would also greatly benefit from a development of antibody-based assays to quantify HMGB1 redox isoforms, presently assessed by mass spectrometry methods.     

MiR-142-3p enhances chemosensitivity of breast cancer cells and inhibits autophagy by targeting HMGB1

MiR-142-3p has been reported to act as a tumor suppressor in breast cancer. However, the regulatory effect of miR-142-3p on drug resistance of breast cancer cells and its underlying mechanism remain unknown. Here, we found that miR-142-3p was significantly downregulated in the doxorubicin (DOX)-resistant MCF-7 cell line (MCF-7/DOX). MiR-142-3p overexpression increased DOX sensitivity and enhanced DOX-induced apoptosis in breast cancer cells. High-mobility group box 1 (HMGB1) is a direct functional target of miR-142-3p in breast cancer cells and miR-142-3p negatively regulated HMGB1 expression. Moreover, overexpression of HMGB1 dramatically reversed the promotion of apoptosis and inhibition of autophagy mediated by miR-142-3p up-regulation. In conclusion, miR-142-3p overexpression may inhibit autophagy and promote the drug sensitivity of breast cancer cells to DOX by targeting HMGB1. The miR-142-3p/HMGB1 axis might be a novel target to regulate the drug resistance of breast cancer patients.