MicroRNA-3666调节白血病细胞PTEN基因的表达*

 目的： 探讨白血病细胞中microRNA-3666（miR-3666）对第10号染色体缺失的磷酸酶和张力蛋白同源基因（PTEN)表达的调控作用。方法: qRT-PCR检测miR-3666在正常人外周血单个核细胞、不同类型白血病细胞系以及临床初诊未治的不同类型白血病细胞中的表达差异,利用TargetScan在线分析软件预测miR-3666潜在靶基因PTEN后,构建含有靶基因野生型3’端非翻译区域(3’UTR)及突变型3’UTR（缺失了整段预测的miR-3666结合序列）的双萤光素酶报告基因质粒,采用脂质体Lipofectamine 2000包裹双萤光素酶重组质粒及miR-3666 模拟体或阴性对照,共转染HEK293T 细胞,应用双萤光素酶检测试剂盒测定萤光素酶活性。FAM标记的miR-3666抑制体和阴性对照分别核转染至K562 细胞,FACS检测转染效率,并采用 Western blotting检测PTEN蛋白的表达。结果: miR-3666 在人白血病细胞系及原代白血病细胞中的表达明显高于正常人外周血单个核细胞,尤其高表达于K562细胞系及原代慢性粒细胞白血病细胞中;双萤光素酶报告基因测定系统验证PTEN是miR-3666的潜在靶基因;K562细胞中下调miR-3666后,Western blotting检测结果显示PTEN蛋白显著上调。结论: 白血病细胞中miR-3666 的表达上调,下调miR-3666后可以促进靶基因PTEN 的表达,miR-3666 有可能成为白血病治疗的新靶点。     

Pae下调miR-106a-5p/PTEN对白血病细胞增殖、凋亡的影响

为探究丹皮酚(paeonol,Pae)调控miR-106a-5p/第10号染色体缺失的磷酸酶及张力蛋白同源物(phosphatase and ten-sion homologue deleted on chromosome 10,PTEN)通路对白血病细胞增殖和凋亡的影响,采用双荧光素酶报告基因分析法验证miR-106...     

ERK5对体外血小板活化及在体血栓的影响

目的:探讨细胞外信号调节激酶5(ERK5)对体外血小板聚集及在体血栓的影响及机制。方法:采用Western blot对人血小板中ERK5的表达及其在血小板活化后的磷酸化水平进行检测;采用血小板聚集仪检测ERK5特异性抑制剂XMD8-92对血小板聚集及致密颗粒释放的影响;采用Fe Cl3颈动脉血栓模型检测ERK5对在体血栓的影响;采用Western blot检测XMD8-92对蛋白激酶B(Akt)和人第10号染色体缺失的磷酸酶及张力蛋白同源蛋白(PTEN)磷酸化的影响。结果:人血小板中存在ERK5的稳定表达,其磷酸化水平在血小板活化后显著升高(P0.05)。XMD8-92可抑制多种血小板激活剂引起的血小板聚集和致密颗粒释放(P0.05)。Western blot结果表明,XMD8-92可通过下调PTEN Ser370位点磷酸化而增强PTEN的活性,从而抑制Akt的磷酸化,这种抑制效果也通过血小板特异PTEN基因敲除小鼠得到了验证。在体血栓研究表明,XMD8-92经尾静脉给药,可显著延长小鼠第一次颈动脉血栓的形成时间。结论:ERK5可通过影响PTEN的磷酸化调节Akt的活化,进而影响到体外血小板的聚集和在体血栓的形成。     

miR-26a调控PTEN基因降低小鼠慢性淋巴白血病细胞的耐药性

目的 观察微小RNA-26a(miR-26a)通过第10号染色体缺失的磷酸酶及张力蛋白同源基因(PTEN)对慢性淋巴细胞白血病(CLL)细胞耐药性的调控作用.方法 实验分为4组:对照组(L1210细胞),耐药组(L1210/DDP细胞)、NC组(转染空载质粒+L1210/DDP细胞)和抑制剂组(转染miR-26a-in...     

槲皮素通过激活PTEN抑制PI3K/AKT及JNK信号通路诱导人乳腺癌细胞凋亡

目的 研究槲皮素对乳腺癌MCF-7细胞增殖活性以及对第10号染色体缺失的磷酸酶和张力蛋白同源物/磷脂酰肌醇3激酶/蛋白激酶B (PTEN/PI3K/AKT)和c-Jun氨基末端激酶(JNK)信号通路的影响。方法 采用CCK-8法检测(0、20、40、60、80、100)μmol/L槲皮素对MCF-7细胞增殖的影响;Hochesst33342染色观察细胞核数量以及核型的变化,流式细胞术检测细胞凋亡;免疫荧光细胞化学染色检测PTEN和磷酸化的JNK(p-JNK)表达,Western blot法检测PTEN、磷酸化的PI3K (p-PI3K)、p-JNK、磷酸化的AKT (p-AKT)蛋白水平;加入PI3K/AKT通路抑制剂LY294002处理后,再次采用以上方法检测对细胞凋亡和相关蛋白表达的影响。结果 随着槲皮素浓度的升高,细胞活性下降,细胞生长受到抑制,且具有浓度依赖性;细胞核浓缩增强、细胞凋亡增加;高浓度槲皮素显著增强PTEN蛋白表达和分布,降低p-PI3K、p-AKT蛋白水平,并抑制p-JNK蛋白的核表达。加入PI3K/AKT信号抑制剂LY294002处理细胞后,LY294002和槲...     

PTEN抑制剂BPV通过下调细胞焦亡水平改善LPS诱导的急性肺损伤

目的：探究第10号染色体丢失的张力蛋白同源磷酸酶基因(PTEN)抑制剂过氧化氢氧化矾酸钾(BPV)对脂多糖(LPS)诱导的急性肺损伤(ALI)的影响及作用机制。方法：将60只雄性C57BL/6小鼠按随机数字表法分为假手术组(Sham组)、BPV组、LPS组和BPV+LPS组,其中又将LPS组分为LPS刺激后6 h、12 h、24 h、48 h组;Western blot检测LPS各组小鼠肺组织中PTEN蛋白表达变化;检测小鼠肺组织湿/干重(W/D),分析Sham组,BPV组、LPS组及BPV+LPS组小鼠肺组织水肿情况;HE染色观察4组小鼠肺组织病理学改变;ELISA和流式细胞术分别检测4组小鼠肺组织灌洗液(BALF)中炎症因子IL-1β、IL-6、IL-18和TNF-α的表达水平及巨噬细胞数量变化;组织免疫荧光染色检测各组小鼠肺泡巨噬细胞中pyrin结构域NLRP3表达;Western blot检测4组小鼠肺组织中NLRP3介导的焦亡途径中NLRP3、caspase-1 p10、ASC和GSDMD p30蛋白表达及PTEN/Akt/NF-κB信号通路中PTEN蛋白、Akt^s...     

腺病毒介导的shRNA下调PTEN表达对体外活化肝星状细胞增殖与凋亡的影响

目的:探讨腺病毒介导的shRNA下调第10号染色体缺失的磷酸酶和张力蛋白同源物基因(PTEN)表达对体外培养的大鼠活化肝星状细胞(HSCs)增殖和凋亡的影响及其信号转导机制。方法:体外培养活化HSCs,以腺病毒为载体将靶向PTEN的shRNA干扰重组体转染至体外活化的大鼠HSCs;四甲基偶氮唑盐(MTT)法检测HSCs增殖;末端转移酶标记技术(TUNEL)及流式细胞术测定HSCs凋亡;Western blotting方法检测PTEN、Bax、Bcl-2、Akt、p-Akt、ERK1/2及p-ERK1/2蛋白表达情况;实时荧光定量PCR方法检测PTEN、Akt及ERK1 mRNA表达情况。结果:(1)靶向PTEN的RNA干扰重组腺病毒成功感染体外活化HSCs,并在一定范围内呈时间依赖性地促进HSCs增殖,腺病毒感染HSCs后72 h,HSCs凋亡率显著下降(P<0.05);(2)Bax表达降低,Bcl-2表达增加(P<0.05);(3)p-Akt和p-ERK1/2蛋白表达显著增加(P<0.05);而Akt蛋白及其mRNA、ERK1蛋白及其mRNA表达均无显著改变(P>0.05)。结论:RNA干扰下调PTEN基因表达可能通过Bcl-2/Bax途径促进体外活化HSCs增殖并抑制其凋亡,此外,RNA干扰下调PTEN基因表达促进p-Akt和p-ERK1/2表达增多,提示PTEN可能通过影响PI3K/Akt和ERK1/2信号通路而在调控HSCs增殖和凋亡中发挥重要作用。     

miR-499a-5p通过靶向Pten减轻嗜铬细胞瘤细胞PC12低氧损伤

目的 研究miR-499a-5p对化学性低氧诱导的嗜铬细胞瘤细胞(PC12)损伤的影响。方法 将PC12细胞分为对照组、低氧组(CoCl₂处理24 h)、低氧+miR-NC组和miR-mimic转染组(分别转染miR-NC和miR-499a-5p mimic后,用CoCl₂处理24 h)。用RT-qPCR检测miR-499a-5p表达;用MTT法检测细胞活性;用试剂盒检测乳酸脱氢酶(LDH)活性;用流式细胞测量术检测各组细胞凋亡;用Western blot检测磷酸酶与张力蛋白同源物(PTEN)蛋白的表达。用荧光素酶报告基因检测Pten是否为miR-499a-5p的直接作用靶标。结果 与对照组比较,低氧组中miR-499a-5p表达和细胞活性降低(P<0.01或P<0.001),LDH活性和细胞凋亡增加(P<0.01或P<0.001);过表达miR-499a-5p可提高低氧条件下PC12细胞的存活率并抑制其凋亡(P<0.05或P<0.01)。Pten是miR-499a-5p的直接作用靶标。结论 miR-499...     

PTEN/PI3K信号通路在大鼠心肌肥厚中的表达

目的:观察PTEN/PI3K信号通路在大鼠心肌组织中的表达,探讨该通路在心肌肥厚发生、发展中的作用.方法:皮下注射异丙肾上腺素(ISO)建立大鼠心肌肥厚模型,测定大鼠体质量、心质量、心肌细胞横径和横截面积;采用免疫组织化学方法检测大鼠心肌组织中肥大标志因子β-肌球蛋白(β-MHC)及PTEN/PI3K信号通路上PTEN、磷脂酰肌醇3激酶(PI3K)、蛋白激酶B(PKB)、死亡相关因子(BAD)蛋白表达;利用计算机图像处理系统对各种蛋白进行定量分析.结果:模型组大鼠全心质量/体质量、左室质量/体质量、心肌细胞横径、心肌细胞截面积较对照组明显增加.模型组大鼠的心肌组织与对照组相比,β-MHC、PI3K与PKB表达水平均升高,PTEN和BAD表达水平明显降低.结论:PTEN在心肌肥厚中表达明显降低,起负性调节作用;PI3K/PKB信号通路激活,可能是导致心肌肥厚的机制之一,BAD可望成为生物学治疗靶点.     

PTEN对缺氧复氧心肌H9c2细胞凋亡、氧化损伤及免疫炎症因子水平的影响

目的:研究第10号染色体缺失的磷酸酶及张力蛋白同源物(PTEN)对缺氧复氧条件下心肌H9c2细胞凋亡、氧化损伤及免疫炎症因子水平的影响。方法:用H9c2细胞构建缺氧复氧模型。细胞转染PTEN小干扰RNA(siRNA)和阴性对照siRNA,缺氧复氧处理后,RT-PCR和Western blot分别测定细胞中PTEN的mRNA和蛋白水平。MTT法测定细胞活力,流式细胞术测定细胞凋亡,用黄嘌呤氧化法测定细胞中超氧化物歧化酶(SOD)活性,用硫代巴比妥酸法测定丙二醛(MDA)含量,用二硝基苯肼法测定培养液上清中乳酸脱氢酶(LDH)活性,ELISA测定培养液上清中肿瘤坏死因子α(TNF-α)、白细胞介素1β(IL-1β)和白细胞介素6(IL-6)水平,Western blot法测定细胞中cleaved caspase-3、Bax和Fas L的蛋白水平。结果:缺氧复氧处理后H9c2细胞中PTEN的mRNA和蛋白水平均明显升高(P 0. 05)。转染PTEN siRNA后的细胞中PTEN的mRNA和蛋白水平明显下降(P 0. 05)。缺氧复氧处理后H9c2细胞活力下降,凋亡率升高,细胞中cleaved caspase-3、Bax和Fas L的蛋白水平升高,MDA水平也升高,SOD活性下降,培养液上清中LDH、TNF-α、IL-1β和IL-6的水平升高(P 0. 05),而下调PTEN可以部分拮抗缺氧复氧对H9c2细胞活力、凋亡率、MDA水平、SOD水平及培养液上清中LDH、TNF-α、IL-1β和IL-6水平的影响。结论:下调PTEN可以减轻缺氧复氧诱导的心肌H9c2细胞氧化损伤,减少H9c2细胞凋亡,降低TNF-α、IL-1β和IL-6的水平。     

MicroRNA-129-5p suppresses proliferation,migration and invasion of retinoblastoma cells through PI3K/AKT signaling pathway by targeting PAX6

BackgroundRetinoblastoma (RB) is the most common primary intraocular malignancy in children. Accumulating evidences have clarified that microRNAs (miRNAs) modulated signaling molecules by acting as oncogenes or tumor-suppressor genes in RB. Thus, in our study, we aimed to investigate the function of miR-129-5p in RB cells through PI3K/AKT signaling pathway by targeting PAX6. Two RB cell lines, Y79 and WERI-Rb-1, were selected in our study, followed by transfection of miR-129-5p inhibitor or si-PAX6 to explore the regulatory role of miR-129-5p in RB cell proliferation, invasion and migration.Material and methodsDual-luciferase assay was used for the detection of targeting relationship between miR-129-5p and PAX6. Besides, western blot analysis was applied to detect expression of cell cycle-related factors (CDK2 and Cyclin E) and PI3K/AKT signaling pathway-related factors (p-AKT and AKT). Nude mice tumorigenesis experiment was used to evaluate the effect of miR-129a-5p on RB growth in vivo.ResultsmiR-129-5p was down-regulated in RB cell lines. miR-129-5p directly targeted the 3′-untranslated region of PAX6. Artificial down-regulation of miR-129-5p promoted cell proliferation, migration and invasion in RB cell lines Y79 and WERI-Rb-1, and promoted RB growth in vivo via PI3K/AKT signaling pathway, which could be reversed by transfection with silencing PAX6.ConclusionThis study provides evidences that RB progression was suppressed by overexpressed miR-129-5p via direct targeting of PAX6 through PI3K/AKT signaling pathway, which may provide a molecular basis for better treatment for RB.     

MiR-508-3p promotes proliferation and inhibits apoptosis of middle ear cholesteatoma cells by targeting PTEN/PI3K/AKT pathway

Cholesteatoma of the middle ear is a common disease in otolaryngology, which can lead to serious intracranial and extracranial complications. Recent studies showed that the dysregulation of microRNA may be involved in the formation of middle ear cholesteatoma. This study aimed to explore the regulatory effect of micro ribonucleic acid 508-3p (miR-508-3p) on proliferation and apoptosis of middle ear cholesteatoma cells and excavate its underlying regulatory mechanism. We found miR-508-3p expression was upregulated in tissues and cells of cholesteatoma which was inversely related to the expression of hsa_circ_0000007. Overexpression of miR-508-3p could notably facilitate cholesteatoma cell proliferation. Luciferase reporter assay showed that miR-508-3p bound the 3''-untranslated region of its downstream mRNA PTEN. Gain and loss of functions of miR-508-3p were performed to identify their roles in the biological behaviors of cholesteatoma cells, including proliferation and apoptosis. Rescue assays confirmed that PTEN could reverse the effect of miR-508-3p overexpression on cell proliferation. In a word, this study validated that the development of cholesteatoma may regulated by hsa_circ_0000007/miR-508-3p/ PTEN/ PI3K/Akt axis.     

Suppressive effect of platycodin D on bladder cancer through microRNA-129-5p-mediated PABPC1/PI3K/AKT axis inactivation

Platycodin D (PD) is a major constituent of Platycodon grandiflorum and has multiple functions in disease control. This study focused on the function of PD in bladder cancer cell behaviors and the molecules involved. First, we administered PD to the bladder cancer cell lines T24 and 5637 and the human uroepithelial cell line SV-HUC-1. Cell viability and growth were evaluated using MTT, EdU, and colony formation assays, and cell apoptosis was determined using Hoechst 33342 staining and flow cytometry. The microRNAs (miRNAs) showing differential expression in cells before and after PD treatment were screened. Moreover, we altered the expression of miR-129-5p and PABPC1 to identify their functions in bladder cancer progression. We found that PD specifically inhibited the proliferation and promoted the apoptosis of bladder cancer cells; miR-129-5p was found to be partially responsible for the cancer-inhibiting properties of PD. PABPC1, a direct target of miR-129-5p, was abundantly expressed in T24 and 5637 cell lines and promoted cell proliferation and suppressed cell apoptosis. In addition, PABPC1 promoted the phosphorylation of PI3K and AKT in bladder cancer cells. Altogether, PD had a concentration-dependent suppressive effect on bladder cancer cell growth and was involved in the upregulation of miR-129-5p and the subsequent inhibition of PABPC1 and inactivation of PI3K/AKT signaling.     

miR-142-5p Encapsulated by Serum-Derived Extracellular Vesicles Protects against Acute Lung Injury in Septic Rats following Remote Ischemic Preconditioning via the PTEN/PI3K/Akt Axis

This study intends to investigate the effects of miR-142-5p encapsulated by serum-derived extracellular vesicles (EVs) on septic acute lung injury (ALI) following remote ischemic preconditioning (RIPC) through a PTEN-involved mechanism. ALI was induced in rats by lipopolysaccharide (LPS) injection, 24 h before which RIPC was performed via the left lower limb. Next, the binding affinity between miR-142-5p and PTEN was identified. EVs were isolated from serum and injected into rats. The morphology of lung tissues, pulmonary edema, and inflammatory cell infiltration into lung tissues were then assessed, and TNF-α and IL-6 levels in serum and lung tissues were measured. The results indicated that RIPC could attenuate ALI in sepsis. miR-142-5p expression was increased in serum, lung tissues, and serum-derived EVs of ALI rats following RIPC. miR-142-5p could target PTEN to activate the PI3K/Akt signaling pathway. miR-142-5p shuttled by serum-derived EVs reduced pulmonary edema, neutrophil infiltration, and TNF-α and IL-6 levels, thus alleviating ALI in LPS-induced septic rats upon RIPC. Collectively, serum-derived EVs-loaded miR-142-5p downregulated PTEN and activated PI3K/Akt to inhibit ALI in sepsis following RIPC, thus highlighting potential therapeutic molecular targets against ALI in sepsis.     

DDX3表达上调在人宫颈癌细胞增殖中的作用分析

目的:探讨DDX3表达上调在人宫颈癌细胞增殖中的作用。方法:采用免疫组织化学方法检测2012年4月至2013年3月河南省人民医院59例宫颈癌组织及癌旁非肿瘤组织标本中的DDX3表达情况。同时,以宫颈癌细胞HeLa为研究对象,通过慢病毒介导的宫颈癌细胞过度表达来检测DDX3的功能。采用细胞增殖与活性检测试剂盒评估细胞存活...     

MicroRNA-133b inhibits proliferation and invasion of ovarian cancer cells through Akt and Erk1/2 inactivation by targeting epidermal growth factor receptor

Aberrant expression of microRNA-133b (miR-133b) has been frequently reported in some cancers excluding ovarian cancer (OC). The role and its molecular mechanism of miR-133b in OC have not been reported. In this study, we explored the effects of miR-133b overexpression on proliferation and invasion in OC cells. The mRNA level of miR-133b in OC cell lines was determined by real-time PCR. The miR-133b mimic was transiently transfected into OC cells using Lipofectamine™ 2000 reagent. Subsequently, cell proliferation and invasion were assessed by MTT, Brdu-ELISA and Transwell assays. Moreover, the effects of miR-133b overexpression on the MAPK and PI3K/Akt signaling pathways were determined by Western blot. Protein level of EGFR was also measured by Western blotting. Meanwhile, luciferase assays were performed to validate EGFR as miR-133b target in OC cells. Our results showed that the mRNA level of miR-133b was remarkably decreased in OC cell lines compared with normal colon epithelium cells, whereas the protein expression of EGFR was significantly increased. Up-regulation of miR-133b inhibited the proliferation and invasion of OC cells. We also found that miR-133b overexpression evidently decreased the phosphorylation of Erk1/2 and Akt. Bioinformatics analysis predicted that the EGFR was a potential target gene of miR-133b. Luciferase reporter assay demonstrated that miR-133b could directly target EGFR. Altogether, our results indicated that miR-133b overexpression was shown to inhibit proliferation and invasion of OC cells through suppression of the MAPK and PI3K/Akt signaling pathways by targeting EGFR.     

Cobalt chloride-stimulated hypoxia promotes the proliferation of cholesteatoma keratinocytes via the PI3K/Akt signaling pathway

Herein, we purposed to explore whether hypoxia triggers proliferation of cholesteatoma keratinocytes via the PI3K-Akt signaling cascade. Cells were inoculated with different concentration of CoCl₂. The proliferation and cellular HIF-1α, p-PDK1 and p‑Akt expression levels of cholesteatoma keratinocytes were assessed in vitro. Hypoxia escalated cell proliferation via upregulating p-PDK1 and p‑Akt expressions. Specific inhibitor of the PI3K-Akt signaling cascade, LY294002 markedly inhibited the expression of p‑Akt and significantly reduces the hypoxia‑induced proliferation of cholesteatoma keratinocytes. Our data provides research evidence confirming that hypoxia participates in the onset and progress of cholesteatoma.     

DICER activates autophagy and promotes cisplatin resistance in non-small cell lung cancer by binding with let-7i-5p

ObjectiveDrug resistance is the main obstacle in the treatment of non-small cell lung cancer (NSCLC). This study aimed to explore the mechanism of DICER in NSCLC resistance and its downstream signaling pathways.MethodsThe A549 cisplatin (DDP)-resistant strain A549/DDP was established. A549/DDP cells were transfected with DICER- and let-7i-5p-related vectors, and treated with autophagy activator rapamycin. The cell viability and apoptosis were tested by CCK-8 assay and flow cytometry, respectively. The formation of autophagosomes was observed with a transmission electron microscopy. RT-qPCR and Western blot assay were conducted to detect expression levels of DICER, let-7i-5p, autophagy-related proteins, and the PI3K/AKT/mTOR pathway-related proteins. The dual luciferase reporter gene assay was implemented to confirm the targeted binding of DICER and let-7i-5p.ResultsDICER was highly expressed in DDP-resistant NSCLC tissues and cells, and DICER could target and negatively regulate the expression of let-7i-5p. DDP treatment could inhibit the viability and promote cell apoptosis of A549/DDP cells. Downregulation of DICER in A549/DDP cells exhibited a decrease of cell viability, a decreased ratio of LC3-II/LC3-I and autophagosomes, together with an elevation of cell apoptosis rate and the phosphorylation levels of PI3K/AKT/mTOR. Treatment of rapamycin and let-7i-5p inhibitor reversed the effects of downregulated DICER in cell viability, ratio of LC3-II/LC3-I, autophagosomes, cell apoptosis rate and the phosphorylation levels of PI3K/AKT/mTOR in A549/DDP cells.ConclusionOur research suggests that DICER promotes autophagy and DDP resistance in NSCLC through downregulating let-7i-5p, and inhibits the activation of PI3K/AKT/mTOR pathway.     

miR-125a-5p通过GSK-3β/Snail信号通路抑制乳腺癌细胞的上皮-间充质转化

目的:探讨微小RNA-125a-5p(miR-125a-5p)通过GSK-3β/Snail信号通路对乳腺癌细胞上皮-间充质转化(EMT)的影响。方法:RT-qPCR检测人正常乳腺上皮细胞与乳腺癌细胞中miR-125a-5p的表达量,同时检测miR-125a-5p质粒在人乳腺癌MDA-MB-231细胞中的转染效率;趋化运动实验与Transwell侵袭实验检测趋化运动能力和侵袭能力;Western blot检测EMT相关标志物的变化,同时检测磷酸化糖原合成酶激酶3β(p-GSK-3β)的蛋白水平及Snail的转核情况。结果:乳腺癌细胞中miR-125a-5p的表达量明显低于人正常乳腺上皮细胞(P0.05);miR-125a-5p在转染miR-125a-5p质粒的MDA-MB-231细胞中表达水平明显增高;MDA-MB-231细胞的趋化运动能力在表皮生长因子(EGF)浓度为10μg/L时最强;在EGF刺激下,与MDA-MB-231/NC细胞组相比,MDAMB-231/miR-125a-5p细胞组的侵袭能力明显降低,上皮钙黏着蛋白(E-cadherin)表达量升高,波形蛋白(vimentin)和p-GSK-3β的蛋白水平明显降低,同时Snail转核受到明显抑制;与MDA-MB-231/miR-125a-5p+Con细胞组相比,MDA-MB-231/miR-125a-5p+GAB2细胞组的侵袭能力明显增强,E-cadherin表达量降低,vimentin和p-GSK-3β的蛋白水平明显升高,同时促进Snail转核。结论:miR-125a-5p可通过GSK-3β/Snail信号通路抑制乳腺癌细胞的EMT,进而抑制乳腺癌细胞的侵袭能力。     

鲍曼不动杆菌外膜蛋白A通过Akt/mTOR/p70S6K信号通路引起RAW264.7细胞自噬

目的:分析鲍曼不动杆菌标准株ATCC 19606(Acinetobacter baumannii ATCC 19606)外膜蛋白A(outer membrane protein A,Omp A)对RAW264. 7细胞的自噬诱导作用。方法:建立Omp A刺激RAW264. 7细胞的模型,通过细胞免疫荧光染色、Western blot和透射电子显微镜检测Omp A对RAW264. 7细胞自噬的影响。结果:Omp A可以引起自噬蛋白LC3B-II表达升高,并抑制Akt/mTOR/p70S6K的磷酸化水平;雷帕霉素可以进一步降低mTOR和p70S6K磷酸化,并提高Omp A引起的LC3B-II表达升高。结论:鲍曼不动杆菌Omp A通过Akt/mTOR/p70S6K信号通路引起RAW264. 7细胞自噬。这为将来进一步研究鲍曼不动杆菌引起自噬的分子机制及找到对抗其感染的新方法提供理论依据。