MiR-215 modulates gastric cancer cell proliferation by targeting RB1

Growing evidence indicates that miRNAs play critical roles in tumorigenesis and cancer progression. Here, we report that miR-215 is significantly up-regulated in gastric cancer tissues from either gastrectomy or gastroscopy. Receiver Operator Characteristic (ROC) curve analysis indicated that miR-215 may be a candidate biomarker for gastric cancer diagnosis. Inhibition of miR-215 significantly suppressed gastric cancer cell proliferation possibly via G1 arrest. Further analyses indicated that miR-215 was able to target retinoblastoma tumor-suppressor gene 1 (RB1) through its 3′-UTR in gastric cancer cells. These data suggest that frequently up-regulated miR-215 in gastric cancer may influence cell proliferation by targeting RB1.     

miR-206对三阴性乳腺癌细胞的增殖抑制作用及初步机制研究

目的 探讨miR-206对三阴性乳腺癌细胞MDA-MB-231增殖的影响及其作用机制。方法 转染miR-206 mimic和miR-NC至乳腺癌细胞株MDA-MB-231中,应用实时荧光定量PCR（qRT-PCR）技术检测miR-206相对表达水平;应用MTT法、克隆形成实验检测miR-206对MDA-MB-231细胞增殖能力的影响;流式细胞术检测miR-206对细胞周期的影响;Western blotting进一步验证miR-206对周期相关蛋白CyclinD2的影响。结果 qRT-PCR检测结果显示,miR-206 mimic转染至MDA-MB-231乳腺癌细胞48h后miR-206的相对表达水平为10.2±1.5。MTT法检测结果显示,miR-206 mimic转染至MDA-MB-231乳腺癌细胞6、24、48、72、96h后的增殖抑制率分别为（0±0.01）％、（0.12±0.03）％、（0.21±0.08）％、（0.28±0.11）％ 和（0.39±0.16）％;克隆形成实验结果显示,miR-206 mimic和miR-NC转染至MDA-MB-231乳腺癌细胞2周后的克隆数目分别为106±35和843±143,差异具有统计学意义（P＜0.01）。流式细胞术检测结果显示,miR-206 mimic转染至MDA-MB-231乳腺癌细胞48h后,明显地阻滞细胞周期于G1期;Western blotting检测显示miR-206表达下调了细胞周期蛋白CyclinD2的表达。结论 miR-206明显抑制了三阴性乳腺癌细胞株MDA-MB-231的增殖,其机制可能与下调细胞周期蛋白CyclinD2的表达有关,这将成为乳腺癌临床治疗一个新的靶点。     

MiR-610 inhibits cell proliferation and invasion in colorectal cancer by repressing hepatoma-derived growth factor

MicroRNAs (miRNAs) act as key regulators of gene expression and their dysregulation is linked to carcinogenesis and tumor progression. MiR-610 has been implicated as an anti-tumor miRNA in multiple types of cancers. However, its biological role and the underlying mechanism in colorectal cancer (CRC) have not been well explored. In this study, we report that miR-610 expression is decreased in CRC samples while ectopic expression of miR-610 suppresses cell proliferation, migration and invasion, and influences the expression of epithelial-mesenchymal transition (EMT)-associated proteins by up-regulating E-cadherin expression and down-regulating vimentin expression. Using a luciferase reporter assay, we reveal that miR-610 directly targets hepatoma-derived growth factor (HDGF) by binding to its 3’UTR. A negative correlation was also observed between miR-610 and HDGF expression in CRC tissues. Further studies show that inhibition of HDGF recapitulates the anti-tumor function of miR-610, whereas re-expression of HDGF partially abrogates the inhibitory effects of miR-610. Collectively, our findings indicate that miR-610 exerts its function by directly targeting HDGF. The miR-610/HDGF axis is a novel therapeutic target for CRC.     

MiR-203 suppresses tumor growth and invasion and down-regulates MiR-21 expression through repressing Ran in esophageal cancer

The expression of miR-203 has been reported to be significantly down-regulated in esophageal cancer. We showed here that overexpression of miR-203 in esophageal cancer cells dramatically increased cell apoptosis and inhibited cell proliferation, migration and invasion as well as tumor growth and down-regulated miR-21 expression. We subsequently identified that small GTPase Ran was a target gene of miR-203. Furthermore, Ran restoration partially counteracted the tumor suppressive effects of miR-203 and increased miR-21 expression. Taken together, our findings suggest that miR-203 may act as novel tumor suppressor in esophageal cancer through down-regulating the expression of Ran and miR-21.     

选择性COX2抑制剂对胃癌细胞增殖的影响

背景与目的：越来越多证据表明非甾体类抗炎药（NSAIDs)可以减少消化道肿瘤的危险,其化学预防作用在于抑制了环氧全酶－2（COX－2）,但选择性COX－2抑制剂对胃癌细胞生长的影响及机制目前3仍不十分清楚。本研究目的是观察选择性COX－2抑制剂尼美舒利对SGC7901胃腺癌细胞PGE2释放及增殖和凋亡的影响。方法：采用MTT比色法和放射免疫分析法观察尼美舒利对SGC7901细胞增殖及前列腺素E（PGE2）释放的影响,采用透射电镜及流式细胞仪观察尼美舒利对SGC7901细胞诱导凋亡的作用及细胞周期的影响。结果：尼美舒利呈时间,剂量依赖性方式抑制SGC7901细胞增殖,减少PGE2释放;改变细胞周期的分布,增加G0／G1期细胞比例,呈剂量依赖性非线型方式诱导其凋亡。结论：尼美舒利可能通过减少PGE2释放,影响细胞周期分布和诱导细胞凋亡,从而抑制SGC7901胃腺癌细胞的增殖,选择性抑制COX－2发挥其抑制人胃癌细胞恶性增殖和诱导凋亡的作用。     

Down-regulation of c-Met and Bcl2 by microRNA-206, activates apoptosis,and inhibits tumor cell proliferation,migration and colony formation

Hsa-miRNA-206 (miR-206), highly expressed in skeletal muscle, has recently been discovered to have anticancer properties in different tissues. However, the role of miR-206 on lung cancer is still ambiguous. In this study, we investigated the role of miR-206 on the development of lung cancer. The results indicated that miR-206 expression was suppressed in lung cancer tissues and very low levels were found in non-small cell lung cancer (NSCLS) cell liness. Transient transfection of miR-206 into cultured A549 and SK-MES-1 cells led to significant decrease in cell growth, migration, invasion and colony formation, and promoted cell apoptosis. Using bioinformatics, we identified putative miR-206 binding sites within the 3′-untranslated region (3′-UTR) of the human c-Met and Bcl2 mRNA. The expression of c-Met and Bcl2 proteins were shown to be down-regulated after treated with miR-206 by subsequent Western blot and qRT-PCR analysis. Conversely, up-regulation of c-Met and Bcl2 were confirmed in tissue samples of human lung cancer, with its level inversely correlated with miR-206 expression. In addition, miR-206 also decreased the gene expression of MMP-9, CCND1 and CCND2 while increased the gene expression of p57 (Kip2) in A549 and SK-MES-1 cells. Taken together, our results demonstrated that miR-206 suppressed c-Met and Bcl2 expression in NSCLS and could function as a potent tumor suppressor in c-Met/Bcl2-over expressing tumors. Inhibition of miR-206 function could contribute to aberrant cell proliferation, migration, invasion and apoptosis, leading to NSCLS development.     

miR-513a-3p靶向鼠双微体基因2对胃癌细胞增殖迁移侵袭的影响

目的探讨miR-513a-3p靶向鼠双微体基因2(MDM2)对胃癌细胞的增殖、迁移和侵袭的影响及其作用机制。方法采用脂质体法将miR-NC、miR-513a-3p、anti-miR-NC、anti-miR-513a-3p、si-NC、si-MDM2、miR-513a-3p+pcDNA3.1和miR-513a-3p+pcDNA3.1-MDM2转染至BGC-823细胞中,采用实时荧光定量聚合酶链反应(qRT-PCR)检测miR-513a-3p的表达水平,采用Western blot检测cyclin D1、MMP-2、p21、E-cadherin和MDM2蛋白的表达水平,四甲基偶氮唑蓝法检测各组胃癌细胞BGC-823的活性,Transwell法检测各组胃癌细胞BGC-823的迁移和侵袭能力,双荧光素酶报告基因检测实验检测miR-513a-3p与MDM2的靶向关系。结果胃癌细胞BGC-823、MGC-803中miR-513a-3p的表达水平分别为0.21±0.02和0.34±0.03,与胃上皮细胞GES-1(0.76±0.08)比较,差异均有统计学意义(均P<0.05)。培养24、48和72 h后,miR-NC组细胞的吸光度(A)值分别为0.57±0.05、1.03±0.10和1.43±0.14,miR-513a-3p组细胞的A值分别为0.36±0.03、0.48±0.05和0.63±0.06,差异均有统计学意义(均P<0.05);miR-NC组细胞的迁移和侵袭数分别为(130±11.80)个和(117±10.60)个,miR-513a-3p组细胞分别为(58±5.64)个和(50±5.13)个,差异均有统计学意义(均P<0.05)。培养24、48和72 h后,si-NC组细胞的A值分别为0.53±0.05、0.95±0.10和1.36±0.14,si-MDM2组细胞的A值分别为0.39±0.04、0.57±0.06和0.80±0.08;si-NC组细胞的迁移和侵袭数分别为(141±12.02)个和(109±10.60)个,si-MDM2组的迁移和侵袭数分别为(66±6.67)个和(61±6.18)个,差异均有统计学意义(均P<0.05)。培养24、48和72 h后,miR-513a-3p+pcDNA3.1组细胞的A值分别为0.34±0.03、0.46±0.05和0.61±0.06,miR-513a-3p+pcDNA3.1-MDM2组细胞的A值分别为0.48±0.05、0.82±0.08和1.17±0.12,差异均有统计学意义(均P<0.05);miR-513a-3p+pcDNA3.1组细胞的迁移和侵袭数分别为(56±5.71)个和(51±5.16)个,miR-513a-3p+pcDNA3.1-MDM2组分别为(113±10.28)个和(104±10.02)个,差异均有统计学意义(均P<0.05)。结论miR-513a-3p可抑制胃癌细胞的增殖、迁移和侵袭能力,其机制可能与靶向调控MDM2的表达有关,可为胃癌的预防和治疗提供新靶点。     

舒林酸抗胃癌细胞体外生长的实验研究

目的观察舒林酸对胃癌BGC-823细胞增殖、凋亡的影响,探讨其作用机制。方法将不同浓度的舒林酸体外作用于人胃癌BGC-823细胞,采用倒置显微镜观察BGC-823细胞形态改变,四甲基偶氮唑蓝（MTT）比色法检测胃癌细胞增殖,流式细胞仪检测胃癌细胞周期分布及凋亡,透射电镜观察凋亡,免疫组化检测ki-67、bcl-2及环氧合酶-2（COX-2）蛋白的表达。结果舒林酸作用后,细胞伪足回缩,变小、变圆,排列松散或聚集成团,出现悬浮现象,瘤巨细胞减少或不见瘤巨细胞。舒林酸可抑制BGC-823细胞增殖,使G0／G1期细胞比例增高,S期细胞比例降低。1．2mmol／L舒林酸作用48h,G0／G1期细胞增至93．8％,S期细胞比例降至3．4％。舒林酸作用后,细胞凋亡率显著上升,1．2mmol／L舒林酸作用48h,细胞凋亡率升至54．9％,而ki-67、bcl-2及COX-2蛋白表达阳性率显著降低;透射电镜可观察到细胞凋亡的形态特征及凋亡小体。上述作用均呈时间和剂量依赖性。结论舒林酸可抑制胃癌BGC--823细胞体外生长,其机制涉及影响细胞周期分布、诱导细胞凋亡及抑制ki-67、bcl-2及COX-2蛋白的表达。     

MiR-145 functions as a tumor suppressor by directly targeting histone deacetylase 2 in liver cancer

Aberrant regulation of histone deacetylase 2 (HDAC2) plays a pivotal role in the development of hepatocellular carcinoma (HCC), but, the underlying mechanism leading to HDAC2 overexpression is not well understood. We performed microRNA (miRNA) profiling analysis in a subset of HCCs, and identified four down-regulated miRNAs that may target HDAC2 in HCC. Ectopic expression of miRNA mimics evidenced that miR-145 suppresses HDAC2 expression in HCC cells. This treatment repressed cancer cell growth and recapitulated HDAC2 knockdown effects on HCC cells. In conclusion, we suggest that loss or suppression of miR-145 may cause aberrant overexpression of HDAC2 and promote HCC tumorigenesis.     

Knockdown of a proliferation-inducing ligand (PRIL) suppresses the proliferation of gastric cancer cells

Purpose: PRIL (proliferation-inducing ligand) is a newly identified member of the tumor necrosis factor (TNF) family and modulates death ligand-induced apoptosis. Here, we investigated the effect of PRIL on cellular characteristics relating to tumor progression in human gastric cancer. Method: Recombinant lentivirus containing PRIL siRNA was constructed and then infected MGC803 and SGC7901 gastric cancer cells. MTT [3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide] colony formation and cell cycle analysis were used to study the effect of PRIL knockdown on gastric cancer cell proliferation. Results: PRIL expression in lentivirus infected cells was significantly reduced as evidenced by quantitative real-time PCR. Cell viability and colony formation of MGC803 and SGC7901 cells were significantly hampered in PRIL knock-down cells. Moreover, the cell cycle was arrested at G2/M phase, elucidating the mechanism underlying the inhibitory effect of siRNA on cell proliferation. Conclusions: Our study indicated that PRIL functions in promoting cell growth, and lentivirus-mediated PRIL gene knockdown might be a promising strategy in the treatment of gastric cancer.     

MiR-122-5p inhibits cell migration and invasion in gastric cancer by down-regulating DUSP4

Objective: To explore the relationship between miR-122-5p and DUSP4 and their effects on gastric cancer (GC) cell mobility and invasiveness.

Methods: Abnormally expressed miRNAs and mRNAs were analyzed using microarrays. The miR-122-5p and DUSP4 mRNA expression levels in GC tissues and cells were determined by RT-qPCR. The target relationship between miR-122-5p and DUSP4 was validated by dual luciferase reporter assay. GC cell mobility and invasiveness were respectively observed by wound healing assay and transwell invasion assay. Western blot and immunohistochemistry were used for detection of the expressions of DUSP4 protein and MMP2 and MMP9 proteins related to cell invasion and migration. The migration and invasion abilities of gastric cancer cells in vivo were evaluated according to the number of lung metastatic nodules in mice.

Results: The expression of miR-122-5p in GC tissues and cells was significantly down-regulated, whereas DUSP4 expression was up-regulated. Bioinformatics prediction strategies and dual luciferase reporter assay verified the binding sites of miR-122-5p on 3′UTR of DUSP4 and the target relationship between miR-122-5p and DUSP4. Overexpression of miR-122-5p and knockdown of DUSP4 in BGC-823 cells observantly suppressed GC cell mobility and invasiveness, whereas downregulation of miR-122-5p expression promoted cell metastasis. MiR-122-5p inhibited GC cell mobility and invasiveness and pulmonary tumor metastasis via downregulation of DUSP4.

Conclusion: MiR-122-5p restrained migration and invasion abilities of GC cells by repressing DUSP4.     

miR-4319通过靶向调控USP2抑制乳腺癌细胞侵袭

目的 探讨miR-4319与泛素特异性蛋白酶2(USP2)表达的相关性以及miR-4319靶向USP2通过核转录因子κB(NF-κB)信号通路对乳腺癌细胞侵袭的影响.方法 实时荧光定量PCR(qRT-PCR)检测miR-4319在正常乳腺癌上皮细胞(MCF10A)、低侵袭性乳腺癌细胞(MCF7)和高侵袭性乳腺癌细胞(M...     

MiR-429 is an independent prognostic factor in colorectal cancer and exerts its anti-apoptotic function by targeting SOX2

Emerging evidence has demonstrated that microRNAs (miRNAs) can act as oncogenes or tumor suppressors to participate in cancer development. In this study, we found that miR-429 expression was up-regulated in human colorectal cancer (CRC) tissues, and the high miR-429 expression was significantly associated with tumor size, lymph node metastasis and poor prognosis. Functionally, miR-429 overexpression suppressed cell apoptosis by directly targeting SOX2 in HT-29 cells. Taken together, our data suggest for the first time that miR-429 could play an oncogenic role in the cellular processes of CRC and represent a novel prognostic biomarker for CRC.     

马齿苋多糖对胃癌SGC7901细胞增殖和凋亡的影响

目的  探讨马齿苋多糖对胃癌SGC7901细胞增殖和凋亡的影响。方法 体外培养胃癌SGC7901细胞,分别用不同浓度（25 μg/mL、50 μg/mL、100 μg/mL、200 μg/mL、300 μg/mL）马齿苋多糖作用胃癌SGC7901细胞,以生理盐水溶液为阴性对照组,5-氟尿嘧啶（5-FU）为阳性对照组,采用MTT法检测细胞增殖情况,流式细胞仪检测细胞凋亡情况。结果 不同浓度马齿苋多糖作用胃癌SGC7901细胞的增殖抑制率随着作用时间的延长和药物浓度的提高而增加。作用48 h后,200 μg/mL、300 μg/mL马齿苋多糖组的细胞增殖抑制率分别为（53.02±2.46）%、（57.20±2.14）%,与5-FU组细胞增殖抑制率（56.36±3.26）%相当（P＞0.05）;各浓度组的细胞凋亡率依次为31.92%、38.39%、40.45%、48.49%、55.71%,与阴性对照组比较均升高（均P＜0.05）;与5-FU组比较,低浓度（25 μg/mL、50 μg/mL、100μg/mL）组的细胞凋亡率降低（P＜0.05）,而高浓度（300 μg/mL）组的细胞凋亡率升高（P＜0.05）。结论 马齿苋多糖可抑制胃癌SGC7901细胞增殖并诱导其凋亡。