Long non-coding RNA OIP5-AS1 promotes the growth of gastric cancer through the miR-367-3p/HMGA2 axis

Increasing evidence shows that aberrant lncRNAs expression contributes to the progression of gastric cancer (GC). The role of the novel lncRNA OIP5-AS1 and its underlying mechanisms in the growth of GC is largely unknown. Here we demonstrate for the first time that OIP5-AS1 expression was up-regulated in GC tissues and cell lines, which significantly correlated with unfavorable clinical characteristics and shorter survival. The results of in vitro and in vivo gain- and loss-of-function experiments indicate that OIP5-AS1 promoted cell proliferation and colony formation while inhibiting apoptosis of GC cells. OIP5-AS1 functioned as an endogenous sponge for miR-367-3p in GC cells. Restoration of miR-367-3p expression abolished the biological effects of OIP5-AS1 on GC cells. Moreover, we show that HMGA2 was a downstream target of miR-367-3p and mediated the effects of OIP5-AS1 on GC cells. OIP5-AS1 regulated the activities of the PI3K/AKT and Wnt/β-catenin pathways through HMGA2. In conclusion, OIP5-AS1 functions as an oncogenic lncRNA that promotes the progression of GC and may serve as a therapeutic target for managing GC.     

萝卜硫素通过下调微小核糖酸-22改善缺氧诱导的心肌H9c2细胞凋亡

目的:研究萝卜硫素(SFP)对缺氧诱导心肌H9c2细胞损伤的保护作用及其机制。方法:缺氧条件为94%N2、5%CO2和1%O2,将细胞在缺氧培养箱中培养构建缺氧损伤模型。采用SFP处理细胞后,CCK8法、Western blot实验和流式细胞术检测H9c2细胞活力、增殖及凋亡相关指标;观察SFP对缺氧诱导H9c2细胞损伤的保护机制,采用RT-PCR和Western blot方法分析了SFP对H9c2细胞中miR-22/PI3K/AKT信号通路的影响。结果:缺氧诱导H9c2细胞增殖活力的降低,促使细胞凋亡;SFP能明显增强H9c2细胞增殖活力,降低其凋亡;缺氧诱导H9c2细胞中miR-22表达上调,SFP前处理可以明显抑制miR-22表达;miR-22高表达能降低SFP前处理对缺氧诱导H9c2细胞损伤的保护作用,而miR-22低表达诱导SFP对H9c2细胞损伤的保护效应;SFP可通过下调H9c2细胞中miR-22表达增高PI3K和AKT的磷酸化。结论:SFP前处理通过下调miR-22表达改善缺氧诱导的H9c2细胞损伤,其作用机制与PI3K/AKT信号通路活化有关。     

PTEN/PI3K/AKT蛋白、miR-21在青海藏族及汉族胃癌患者癌组织中的表达差异

目的探讨PTEN/PI3K/AKT蛋白、miR-21在青海藏族及汉族胃癌患者癌组织中的表达差异。方法选取2016年12月至2018年12月我院胃肠外科进行手术的78例胃癌患者为研究对象(藏族38例,汉族40例)。采用实时荧光定量PCR法检测癌组织标本及癌旁组织中miR-21水平,采用免疫组化染色法检测PTEN/PI3K/AKT蛋白,分析不同民族胃癌患者不同组织PTEN/PI3K/AKT蛋白、miR-21表达情况,同时分析其与临床病理特征之间的关系。结果汉族、藏族胃癌患者癌组织中miR-21表达水平高于癌旁组织(P<0.05),且汉族癌组织中miR-21表达水平明显高于藏族(P<0.05)。汉族、藏族胃癌患者癌组织中PTEN、PI3K、AKT蛋白阳性率比较,差异均有统计学意义(P<0.05),其中汉族胃癌组织中PTEN蛋白阳性率低于藏族,但PI3K、AKT蛋白阳性率高于藏族(P<0.05)。两民族胃癌组织中的PTEN、AKT蛋白、miR-21表达与TNM分期、分化程度、淋巴转移相关(P<0.05),PI3K蛋白表达与TNM分期、淋巴转移相关(P<0.05)。在汉族、藏族胃癌患者中,miR-21与PTEN蛋白均呈负相关,与PI3K、AKT蛋白均呈正相关(P<0.05)。结论PTEN在藏族、汉族胃癌患者中表达水平降低,且汉族表达低于藏族,且PTEN与PI3K、AKT呈负相关,miR-21可能通过抑制PTEN,激活PI3K、AKT信号通路从而参与胃癌患者的发生、发展。     

circZFR promotes cell proliferation and migration by regulating miR-511/AKT1 axis in hepatocellular carcinoma

BackgroundEmerging data suggest the crucial regulatory roles of circular RNAs (circRNAs) in hepatocellular carcinoma (HCC). However, the pathophysiology role of circZFR in HCC remains largely unknown.AimsThis study aims to disclose the functions of circZFR in HCC progression and its potential molecular mechanism.MethodscircZFR and miR-511 were identified by qRT-PCR. Colony formation assay, wound-healing assay, transwell assay, and flow cytometry assay were performed to determine the cell proliferation, migration, invasion and apoptosis. Western blotting and immunohistochemistry (IHC) were utilized to evaluate the expression level of AKT1, GSK3β, β-catenin and cascades of proliferation-related proteins both in vitro and in vivo. Dual luciferase reporter assay was conducted to evaluate the interactions among circZFR, miR-511 and AKT1.ResultsThe expression of circZFR was enhanced and the expression of miR-511 was down-regulated in HCC tissues and cells. Functionally, circZFR silencing or miR-511 overexpression suppressed cell proliferation, migration and invasion, and induced apoptosis of HCC cells. Mechanistically, circZFR acted as a miR-511 sponge to up-regulate its target gene AKT1, which activated cascades of proliferation-related proteins (c-Myc, cyclin D1, Survivin and Bcl-2). Furthermore, depletion of circZFR inhibited tumorigenesis and decreased the expression level of AKT1 in xenograft models.ConclusioncircZFR promotes HCC progression by directly down-regulating miR-511 to activate AKT1 signaling, suggesting that circZFR is a potential target in HCC treatment. Targeting circZFR may provide therapeutic benefits for HCC.     

大黄酸通过miR-29c-3p调节FSCN1的表达影响胃癌细胞的生物学行为

目的 探讨大黄酸(Rhein)对人胃癌细胞(SGC-7901)增殖、迁移、侵袭、凋亡的影响及其机制.方法 通过qRT-PCR检测大黄酸处理后细胞中miR-29c-3p的表达以及miR-29c-3p的转染效率;miR-29c-3p mimics组、NC mimics组、Rhein+miR-29c-3p inhibitor...     

miR-1303 Targets Claudin-18 Gene to Modulate Proliferation and Invasion of Gastric Cancer Cells

Background

MicroRNAs have emerged as important gene regulators and are recognized as important molecules in carcinogenesis. However, the effects of microRNA-1303 (miR-1303) on gastric cancer (GC) cells and the upstream regulation of GC-associated claudin-18 gene (CLDN18) remain unclear. miR-1303 may be involved in the tumorigenesis of GC by targeting CLDN18.

Aims

The purpose of this study was to explore the effect of miR-1303 targeting of CLDN18 on the proliferation, migration and invasion of human GC cells.

Methods

The expression of miR-1303 and claudin-18 in GC tissues and gastric cancer cell lines were detected by qRT-PCR and western blotting, respectively. CCK8 and colony formation assays were performed to study the influence of miR-1303 on the proliferation of the GC cell lines. Transwell and wound-healing assays were carried out to investigate the effect of miR-1303 on the invasion and migration of GC cell lines. Luciferase reporter assays, restore assays and western blotting were used to demonstrate whether CLDN18 is a direct target of miR-1303.

Results

miR-1303 was significantly overexpressed whereas claudin-18 was downregulated in GC tissues and cell lines, which was significantly associated with tumor size, location invasion, histologic type and tumor-node-metastasis stage. Cell proliferation rates were reduced, and cell invasion and migratory ability was significantly restricted in miR-1303 inhibitor-transfected groups. miR-1303 could bind to the putative binding sites in CLDN18 mRNA 3′-UTR and visibly lower the expression of claudin-18. The introduction of claudin-18 without 3′-UTR restored the miR-1303 promoting migration function.

Conclusions

Downregulation of miR-1303 can inhibit proliferation, migration and invasion of GC cells by targeting CLDN18.     

Semaphorin 5A Promotes Gastric Cancer Invasion/Metastasis via Urokinase-Type Plasminogen Activator/Phosphoinositide 3-Kinase/Protein Kinase B

Background

Semaphorin 5A, a member of the semaphorin family, was originally identified as an axonal guidance factor functioning during neuronal development. Previously, we showed that the expression of semaphorin 5A might contribute to the metastasis of gastric cancer. However, less information is currently available as to the involvement of uPA in the semaphorin 5A-induced metastasis and invasion of gastric cancer cells.

Aim

The present study was designed to test whether semaphorin 5A mediates the invasion and metastasis of gastric cancer via PI3K/Akt/uPA signaling.

Methods

The semaphorin 5A-overexpressing cell was established from the gastric cancer cell line AGS. The effect of semaphorin 5A on the expression of uPA was evaluated by ELISA and Western blotting as well as RT-PCR assays, respectively. Synthetic or natural inhibitors and dominant-negative mutants were used to determine the hierarchical relationship between semaphorin 5A, PI3K/Akt and uPA in the invasion and metastasis of gastric cancer.

Results

Overpression of semaphorin 5A enhanced the expression of uPA, and synthetic or natural inhibitors of uPA abolished semaphorin 5A-induced cell migration and invasion. Semaphorin 5A overexpression promoted the phosphorylation of Akt. Blocking effects of PI3K/Akt using pharmacologic inhibitors, dominant-negative mutants abolished the ability of semaphorin 5A to induce uPA expression and cell invasion and migration.

Conclusion

Semaphorin 5A could promote invasion and metastasis of gastric cancer through the PI3K/Akt/uPA signal transduction pathway. Semaphorin 5A and its regulated molecules could be the potential targets for cancer therapy.     

miR-874 Inhibits cell proliferation,migration and invasion through targeting aquaporin-3 in gastric cancer

Background

Aquaporin-3 (AQP3) is a water transporting protein which plays an oncogenic role in several malignant tumors. However, its regulatory mechanism remains elusive to date. In this study, we investigated the microRNA-mediated gene repression mechanism involved in AQP3's role.

Methods

The potential microRNAs targeting AQP3 were searched via bioinformatic methods and identified by luciferase reporter assays, microRNA RT–PCR and western blotting. The expression patterns of miR-874 and AQP3 in human gastric cancer (GC) specimens and cell lines were determined by microRNA RT-PCR and western blotting. 5-ethynyl-2′-deoxyuridine, cell migration and invasion assays and tumorigenicity in vivo were adopted to observe the effects of miR-874 depletion or ectopic miR-874 expression on GC cell phenotypes. Cell apoptosis was evaluated by FACS and TUNEL in vitro and in vivo respectively.

Results

miR-874 suppressed AQP3 expression by binding to the 3′UTR of AQP3 mRNA in GC cells. miR-874 was significantly down-regulated and reversely correlated with AQP3 protein levels in clinical samples. Analysis of the clinicopathological significance showed that miR-874 and AQP3 were closely correlated with GC characteristics. Functional analyses indicated that ectopic miR-874 expression suppressed the growth, migration, invasion and tumorigenicity of GC cells, whereas miR-874 knockdown promoted these phenotypes. Down-regulation of Bcl-2, MT1-MMP, MMP-2 and MMP-9 and upregulation of caspase-3 activity and Bax were involved in miR-874 inducing cell apoptosis, and inhibiting migration and invasion.

Conclusions

These results provide a mechanism by which AQP3 is upregulated, as well as highlight the importance of miR-874 in gastric cancer development and progression.     

MicroRNA-24 attenuates vascular remodeling in diabetic rats through PI3K/Akt signaling pathway

Background and aimsThe vascular remodeling plays a crucial role in pathogenesis of diabetic cardiovascular complications. In this study, we intended to explore the effects and potential mechanisms of microRNA-24 (miR-24) on vascular remodeling under diabetic conditions.Methods and ResultsMiR-24 recombinant adenovirus (Ad-miR-24-GFP) was used to induce miR-24 overexpression either in carotid arteries or high glucose (HG)-induced vascular smooth muscle cells (VSMCs). Cell proliferation was analyzed using CCK-8 method. Cell migration was examined using wound-healing and transwell assay. mRNA and protein expressions of critical factors were, respectively, measured by real-time PCR and western blot as follows: qRT-PCR for the levels of miR-24, PIK3R1; western blot for the protein levels of PI3K (p85α), Akt, p-Akt, mTOR, p-mTOR, 4E-BP1, p-4E-BP1, p70s6k, p-p70s6k, MMP 2, MMP 9, collagen Ⅰ, as well as collagen Ⅲ. Carotid arteries in diabetic rats suffered balloon injury were harvested and examined by HE, immunohistochemical and Masson trichrome staining.The expression of miR-24 was decreased in HG-stimulated VSMCs and balloon-injured carotid arteries of diabetic rats, accompanied by increased mRNA expression of PIK3R1. The up-regulation of miR-24 suppressed VSMCs proliferation, migration, collagen deposition not only induced by HG in vitro, but also in balloon-injured diabetic rats, which were related to inactivation of PI3K/Akt signaling pathway.ConclusionThe up-regulation of miR-24 significantly attenuated vascular remodeling both in balloon-injured diabetic rats and HG-stimulated VSMCs via suppression of proliferation, migration and collagen deposition by acting on PIK3R1 gene that modulated the PI3K/Akt/mTOR axes.     

Silencing profilin-1 inhibits gastric cancer progression via integrin β1/focal adhesion kinase pathway modulation

AIM:To investigate the role of profilin-1(PFN1)in gastric cancer and the underlying mechanisms.METHODS:Immunohistochemical analysis,quan-titative real-time polymerase chain reaction(q RTPCR)and Western blot were performed to detect PFN1expression in clinical gastric carcinoma and adjacent tissues,and the association of PFN1 expression with patient clinicopathological characteristics was analyzed.PFN1 was knocked down to investigate the role of this protein in cell proliferation and metastasis in the SGC-7901 cell line.To explore the underlying mechanisms,the expression of integrinβ1 and the activity of focal adhesion kinase(FAK)and the downstream proteins extracellular-regulated kinase(ERK)1/2,P38 mitogen-activated protein kinase(MAPK),phosphatidylinositol 3-kinase(PI3K),AKT and mammalian target of rapamycin(m TOR)were measured through Western blot or q RT-PCR analysis.Fibronectin(FN),a ligand of integrinβ1,was used to verify the correlation between alterations in the integrinβ1/FAK pathway and changes in tumor cell aggressiveness upon PFN1 perturbation.RESULTS:Immunohistochemical,Western blot and q RT-PCR analyses revealed that PFN1 expression was higher at both the protein and m RNA levels in gastric carcinoma tissues compared with the adjacent tissues.In addition,high PFN1 expression(53/75,70.4%)was correlated with tumor infiltration,lymph node metastasis and TNM stage in gastric cancer,but not with gender,age,location,tumor size,or histological differentiation.In vitro experiments showed that PFN1knockdown inhibited the proliferation of SGC-7901cells through the induction G0/G1 arrest.Silencing PFN1 inhibited cell migration and invasion and downregulated the expression of matrix metalloproteinase(MMP)-2 and MMP9.Moreover,silencing PFN1 reduced the expression of integrinβ1 at the protein level and inhibited the activity of FAK,and the downstream effectors ERK1/2,P38MAPK,PI3K,AKT and m TOR.FN-promoted cell proliferation and metastasis via the integrinβ1/FAK pathway was ameliorated by PFN1silencing.CONCLUSION:These findings suggest that PFN1 plays a critical role in gastric carcinoma progression,and these effects are likely mediated through the integrinβ1/FAK pathway.     

MicroRNA-21 promotes phosphatase gene and protein kinase B/phosphatidylinositol 3-kinase expression in colorectal cancer

AIM: To explore the regulatory mechanism of the target gene of microRNA-21 (miR-21), phosphatase gene (PTEN), and its downstream proteins, protein kinase B (AKT) and phosphatidylinositol 3-kinase (PI3K), in colorectal cancer (CRC) cells.METHODS: Quantitative real-time PCR (qRT-PCR) and Western blot were used to detect the expression levels of miR-21 and PTEN in HCT116, HT29, Colo32 and SW480 CRC cell lines. Also, the expression levels of PTEN mRNA and its downstream proteins AKT and PI3K in HCT116 cells after downregulating miR-21 were investigated.RESULTS: Comparing the miR-21 expression in CRC cells, the expression levels of miR-21 were highest in HCT116 cells, and the expression levels of miR-21 were lowest in SW480 cells. In comparing miR-21 and PTEN expression in CRC cells, we found that the protein expression levels of miR-21 and PTEN were inversely correlated (P < 0.05); when miR-21 expression was reduced, mRNA expression levels of PTEN did not significantly change (P > 0.05), but the expression levels of its protein significantly increased (P < 0.05). In comparing the levels of PTEN protein and downstream AKT and PI3K in HCT116 cells after downregulation of miR-21 expression, the levels of AKT and PI3K protein expression significantly decreased (P < 0.05).CONCLUSION: PTEN is one of the direct target genes of miR-21. Thus, phosphatase gene and its downstream AKT and PI3K expression levels can be regulated by regulating the expression levels of miR-21, which in turn regulates the development of CRC.     

Downregulation of microRNA-126 in endothelial progenitor cells from diabetes patients, impairs their functional properties, via target gene Spred-1

Diabetes mellitus (DM) adversely affects the number and function of circulating endothelial progenitor cells (EPCs). Consequently, there is also a reduction in the repair mechanism of these cells, which is a critical and initiating factor in the development of diabetic vascular disease. The aim of the present study was to analyze miR expression profiles in EPCs from patients with DM and choose the most significantly regulated miR to study its possible role on EPC dysfunction and elucidate its mechanism of action. EPCs were collected from subjects with Type II DM and non-diabetic control subjects. Total RNA was harvested from EPCs, and a total of 5 candidate miRNAs were identified by microarray screening and were quantified by TaqMan real-time PCR. Lentiviral vectors expressing miR-126 and miR-126 inhibitor (anti-miR-126) were transfected into EPCs, and the EPC colony-forming capacity, proliferation activity, migratory activity, differentiation capacity, and apoptotic susceptibility were determined and Western Blotting and mRNA real-time PCR analyses were performed. To study the mechanisms, lentiviral vectors expressing Spred-1 and a short interfering RNA (siRNA) targeting Spred-1 were prepared. Five miRs were aberrantly downregulated in EPCs from DM patients. These miRs included miR-126, miR-21, miR-27a, miR-27b and miR-130a. Anti-miR-126 inhibited EPC proliferation, migration, and enhanced apoptosis. Restored miR-126 expression in EPCs from DM promoted EPC proliferation, migration, and inhibited EPC apoptosis ability. Despite this, miR-126 had no effect on EPC differentiation. miR-126 overexpression significantly downregulated Spred-1 in EPCs. The knockdown of Spred-1 expression in EPCs from DM promoted proliferation, migration, and inhibited apoptosis of the cells. The signal pathway of miR-126 effecting on EPCs is partially mediated through Ras/ERK/VEGF and PI3K/Akt/eNOS regulation. This study provides the first evidence that miR-126 is downregulated in EPCs from diabetic patients, and impairs EPCs-mediated function via its target, Spred-1, and through Ras/ERK/VEGF and PI3K/Akt/eNOS signal pathway.     

MiR-628–5p Inhibits Cervical Carcinoma Proliferation and Promotes Apoptosis by Targeting VEGF

BackgroundIt has been reported that the dysregulation of microRNAs (miRNAs) is implicated in the biological processes of diverse diseases, including the tumorigenesis of human cancers. MicroRNA-628–5p (miR-628–5p) is differentially expressed and plays a critical role in several cancers, but the role of miR-628–5p in cervical cancer has not been well studied.MethodsThe TCGA database and RT-qPCR were used to evaluate the expression profile of miR-628–5p in cervical cancer tissues. Transfection efficiency of synthetic miRNAs was detected using RT-qPCR. The biological effects of miR-628–5p on cervical cancer cells were assessed by the CCK-8 assay, flow cytometry, western blot analysis, and the tube formation assay. The expression levels of key proteins involved in cell apoptosis, the cell cycle and the PI3K pathway were analyzed by western blot analysis. Bioinformatic analysis and the luciferase reporter assay were performed to investigate the targeted relationship between miR-628–5p and vascular endothelial growth factor (VEGF).ResultsMiR-628–5p was downregulated and negatively correlated with Ki-67 expression in cervical cancer tissues, and its low level predicted poor survival of patients. Functional assays indicated that miR-628–5p inhibited cell proliferation and promoted cell apoptosis. Mechanically, VEGF was verified to be a downstream target of miR-628–5p. Moreover, overexpression of VEGF could reverse the effects of miR-628–5p on VEGF/PI3K/AKT signaling, cell proliferation, apoptosis, the cell cycle and angiogenesis in cervical cancer.ConclusionsMiR-628–5p inhibited cervical cancer cell proliferation and promoted apoptosis by targeting VEGF.     

Lipotoxic hepatocyte-derived exosomal miR-1297 promotes hepatic stellate cell activation through the PTEN signaling pathway in metabolic-associated fatty liver disease

BACKGROUNDExosomes play an important role in metabolic-associated fatty liver disease (MAFLD), but the mechanism by which exosomes participate in MAFLD still remain unclear.AIMTo figure out the function of lipotoxic exosomal miR-1297 in MAFLD.METHODSMicroRNA sequencing was used to detect differentially expressed miRNAs (DE-miR) in lipotoxic exosomes derived from primary hepatocytes. Bioinformatic tools were applied to analyze the target genes and pathways regulated by the DE-miRs. Quantitative real-time PCR (qPCR) was conducted for the verification of DE-miRs. qPCR, western blot, immunofluorescence staining and ethynyl-20-deoxyuridine assay were used to evaluate the function of lipotoxic exosomal miR-1297 on hepatic stellate cells (LX2 cells). A luciferase reporter experiment was performed to confirm the relationship of miR-1297 and its target gene PTEN. RESULTSMicroRNA sequencing revealed that there were 61 exosomal DE-miRs (P < 0.05) with a fold-change > 2 from palmitic acid treated primary hepatocytes compared with the vehicle control group. miR-1297 was the most highly upregulated according to the microRNA sequencing. Bioinformatic tools showed a variety of target genes and pathways regulated by these DE-miRs were related to liver fibrosis. miR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes by qPCR. Fibrosis promoting genes (α-SMA, PCNA) were altered in LX2 cells after miR-1297 overexpression or miR-1297-rich lipotoxic exosome incubation via qPCR and western blot analysis. Immunofluorescence staining and ethynyl-20-deoxyuridine staining demonstrated that the activation and proliferation of LX2 cells were also promoted after the above treatment. PTEN was found to be the target gene of miR-1297 and knocking down PTEN contributed to the activation and proliferation of LX2 cells via modulating the PI3K/AKT signaling pathway.CONCLUSIONmiR-1297 was overexpressed in exosomes derived from lipotoxic hepatocytes. The lipotoxic hepatocyte-derived exosomal miR-1297 could promote the activation and proliferation of hepatic stellate cells through the PTEN/PI3K/AKT signaling pathway, accelerating the progression of MAFLD.     

miR-451对食管癌EC9706细胞增殖、凋亡及侵袭能力的影响

目的:探讨miR-451对食管癌EC9706细胞增殖、凋亡及侵袭能力的影响.方法:化学合成miR-451mimics,脂质体包裹转染EC9706细胞为miR-451组,同时设立无关序列(Scramble-miR)对照组、脂质体对照组和空白对照组.转染后48h,荧光定量RT-PCR检测miR-451表达量的变化,Westernblot检测Bcl-2、AKT和磷酸化AKT蛋白表达水平,流式细胞仪检测细胞凋亡情况,Transwell侵袭实验检测细胞侵袭能力的改变;MTT法检测转染后l、2、3、4、5、6d各组细胞增殖率.结果:miR-451组的miR-451表达水平显著上调(P<0.01,F=69.26),为空白对照组的15.84倍;miR-451组细胞Bcl-2、AKT和磷酸化AKT蛋白表达均显著下调(P<0.05,F=5.83);miR-451组细胞凋亡率为12.07%±1.12%,与3个对照组比较显著升高(P<0.01,F=26.72);miR-451组平均侵袭细胞数为47.4±7.4,与3个对照组比较显著降低(P<0.01,F=34.55).miR-451组细胞的生长在转染后2d出现显著抑制(P<0.05,F=5.95),并且随时间的延长而日益显著.结论:上调miR-451表达可抑制食管癌EC9706细胞增殖和侵袭,促进细胞凋亡.     

沉默miR-107对乳腺癌细胞侵袭及上皮-间质转化的影响

目的 探究miR-107对乳腺癌细胞侵袭及上皮-间质转化(EMT)的影响和机制。方法 利用荧光定量PCR方法分析miR-107在正常乳腺细胞及乳腺癌细胞系中的表达差异;HS578T细胞分别转染对照miRNA和miR-107抑制剂,利用划痕实验分析细胞迁移能力,用Transwell实验分析细胞侵袭能力,用实时荧光定量PCR方法检测细胞EMT标志物的表达水平,用蛋白质免疫印迹实验检测细胞PTEN/AKT信号通路。结果 与正常乳腺细胞相比,miR-107在乳腺癌细胞株中高表达;沉默miR-107的表达抑制HS578T细胞的迁移、侵袭及EMT,促进PTEN/AKT信号通路。结论 miR-107在乳腺癌细胞中高表达,沉默miR-107表达通过PTEN/AKT信号通路抑制乳腺癌细胞迁移、侵袭和EMT。     

Involvement of PI3K/PTEN/AKT/mTOR pathway in invasion and metastasis in hepatocellular carcinoma: Association with MMP-9

Aim:  To investigate the status of Phosphatidylinositol 3-kinase (PI3K)/PTEN/AKT/mammalian target of rapamycin (mTOR) pathway and its correlation with clinicopathological features and matrix metalloproteinase-2, -9 (MMP-2, 9) in human hepatocellular carcinoma (HCC).
Methods:  PTEN, Phosphorylated AKT (p-AKT), Phosphorylated mTOR (p-mTOR), MMP-2, MMP-9 and Ki-67 expression levels were evaluated by immunohistochemistry on tissue microarrays containing 200 HCCs with paired adjacent non-cancerous liver tissues. PTEN, MMP-2 and MMP-9 mRNA levels were determined by real-time RT-PCR in 36 HCCs. The relationships between PI3K/PTEN/AKT/mTOR pathway and clinicopathological factors and MMP-2, 9 were analyzed in HCC.
Results:  In HCC, PTEN loss and overexpression of p-AKT and p-mTOR were associated with tumor grade, intrahepatic metastasis, vascular invasion, TNM stage and high Ki-67 labeling index ( P  < 0.05). PTEN loss was correlated with p-AKT, p-mTOR and MMP-9 overexpression. Furthermore, PTEN and MMP-2, 9 mRNA levels were down-regulated and up-regulated in HCC compared with paired non-cancerous liver tissues, respectively ( P  < 0.01). PTEN, MMP-2 and MMP-9 mRNA levels were correlated with tumor stage and metastasis. There was an inverse correlation between PTEN and MMP-9 mRNA expression. However, PI3K/PTEN/AKT/mTOR pathway was not correlated with MMP-2.
Conclusions:  PI3K/PTEN/AKT/mTOR pathway, which is activated in HCC, is involved in invasion and metastasis through up-regulating MMP-9 in HCC.