Long non-coding RNA ZFAS1 regulates the malignant progression of gastric cancer via the microRNA-200b-3p/Wnt1 axis

Gastric cancer is a common malignant tumor. Studies from our laboratory or others have shown that long non-coding RNA (lncRNA) zinc finger antisense (ZFAS)1 often acts as an oncogene. However, the molecular underpinnings of how ZFAS1 regulates gastric cancer remain to be elucidated. Results showed that ZFAS1 expression was upregulated, and microRNA-200b-3p (miR-200b) expression was downregulated in gastric cancer tissues. MiR-200b overexpression suppressed the proliferation, cell cycle process, and Wnt/β-catenin signaling of gastric cancer cells. Subsequently, we identified miR-200b is a target of ZFAS1 and Wnt1 is a target of miR-200b. Furthermore, promotion of cancer malignant progression and activation of Wnt/β-catenin signaling induced by ZFAS1 was counteracted by increasing miR-200b expression. In vivo, ZFAS1 knockdown suppressed the tumorigenesis with the upregulated miR-200b and the inactive Wnt/β-catenin signaling. Summarily, we demonstrated a critical role of miR-200b in gastric cancer, and ZFAS1 can promote malignant progression through regulating miR-200b mediated Wnt/β-catenin signaling.     

Linc01776在椎间盘退行性变中生物学功能的研究

目的:椎间盘退行性变(intervertebral disc degeneration, IVDD)是中老年人中的高发病率与高致残率的疾病,目前其病理生理机制尚未完全研究清楚。本实验旨在研究linc01776在IVDD中的差异性表达,并通过生物信息学探索调控IVDD的分子学机制,从而为IVDD的治疗提供作用靶点。方法:根据Pffirrmann评分,将退变椎间盘标本分成对照组与IVDD组,通过qRT-PCR验证linc01776在退变椎间盘中的差异表达;构建Linc01776敲除质粒表达载体,并研究Linc01776在IVDD中生物功能学研究;预测Linc01776参与的竞争性内源RNA (CeRNA)调控机制。结果:linc01776在退变椎间盘中表达显著增加。敲除linc01776后,Aggrecan表达增加,MMP3、MMP13表达减少,细胞外基质分解降低。通过生物信息学预测Linc01776/miR-196b-5p/Akt1的CeRNA机制调控通路。结论:Linc01776促进髓核细胞外基质降解,调控IVDD的发生与发展。Linc01776/miR-196b-5p/Akt1信号轴可能为其调控IVDD进程的CeRNA机制调控通路。     

Linc00210 enhances the malignancy of thyroid cancer cells by modulating miR-195-5p/IGF1R/Akt axis

Emerging evidence has indicated that long noncoding RNA (lncRNAs) play crucial roles in regulating thyroid cancer (TC) development. Linc00210 is a newly identified lncRNA which plays an oncogenic role in hepatocellular carcinoma and nasopharyngeal carcinoma, but whether Linc00210 can modulate the development of TC remains elusive. Here, we found that Linc00210 expression was upregulated in TC tissues compared to the matched noncancerous tissues. Overexpression of Linc00210 augmented the proliferation, migration, and invasion of TC cells. Mechanistically, Linc00210 served as a sponge for miR-195-5p, thereby counteracting its ability in downregulating the expression of IGF1R and the activation of PI3K/Akt signaling. Moreover, inhibition of Linc00210 suppressed the growth of TC cells in nude mice. Our findings for the first time uncovered the oncogenic property of Linc00210 in TC.     

Long noncoding RNA Linc00339 promotes triple-negative breast cancer progression through miR-377-3p/HOXC6 signaling pathway

Recently, long noncoding RNAs (lncRNAs) have become the key gene regulators and prognostic biomarkers in various cancers. Through microarray data, Linc00339 was identified as a candidate oncogenic lncRNA. We compared the expression levels of Linc00339 in several breast cancer cell lines and normal mammary gland epithelial cell line. The effects of Linc00339 on tumor progression were examined both in vitro and in vivo. 3-(4,5-Dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays were applied to evaluate the functions of Linc00339, miR-377-3p, and HOXC6 on cell proliferation. Flow cytometry analysis was used to detect apoptosis and cell cycle distribution. Overall survival (OS) was analyzed using data from The Cancer Genome Atlas and molecular taxonomy of breast cancer international consortium (METABRIC). Dual luciferase assay and RNA immunoprecipitation were performed to confirm the interaction between Linc003339 and miR-377-3p. Linc00339 was increased in breast cancer cell lines compared with the normal epithelial cell. Through in vitro and in vivo experiments, Linc00339 overexpression promoted triple-negative breast cancer (TNBC) proliferation, inhibited cell cycle arrest, and suppressed apoptosis. Silencing of Linc00339 obtained the opposite effects. Mechanistic investigations demonstrated that Linc00339 could sponge miR-377-3p and regulate its expression. Higher expression of miR-377-3p indicated longer OS in breast cancer patients, especially in TNBC patients. Overexpression of miR-377-3p retarded TNBC cell growth through regulating cell cycle distribution and apoptosis. And miR-377-3p was involved in Linc00339-mediated TNBC proliferation through regulating HOXC6 expression. Knockdown of HOXC6 inhibited TNBC progression. In conclusion, our results illuminated that the novel Linc00339/miR-377-3p/HOXC6 axis played a critical role in TNBC progression and might be a promising therapeutic target for TNBC treatment.     

LncRNA Linc00511 promotes osteosarcoma cell proliferation and migration through sponging miR-765

Long noncoding RNA (lncRNA) Linc00511 is a novel lncRNA, and it was reported to play important roles in the progression and carcinogenesis of several tumors. However, the expression and biological roles of Linc00511 in osteosarcoma were still unknown. In this research, we showed that the expression of Linc00511 was upregulated in osteosarcoma samples and cell lines. Ectopic expression of Linc00511 promoted osteosarcoma cell growth, colony formation, and migration. Moreover, overexpression of Linc00511 enhanced the epithelial-mesenchymal transition progression in osteosarcoma cell. In addition, we showed that elevated expression of Linc00511 suppressed microRNA-765 (miR-765) expression and promoted apurinic/apyrimidinic endonuclease 1 (APE1) expression in osteosarcoma cell. The expression of miR-765 was downregulated in osteosarcoma cells and samples and was negatively related to Linc00511 expression in osteosarcoma tissues. Ectopic expression of miR-765 inhibited osteosarcoma cell growth and migration. Furthermore, we showed that Linc00511 overexpression promoted MG-63 cells proliferation, colony formation, and migration via downregulation of miR-765. These results suggested that Linc00511 played as an oncogene in the development of osteosarcoma.     

Long noncoding RNA linc00467 plays an oncogenic role in hepatocellular carcinoma by regulating the miR-18a-5p/NEDD9 axis

Increasing evidence has shown that numerous long noncoding RNAs (lncRNAs) play critical roles in tumorigenesis. Herein, we investigated the biological role of lncRNA linc00467 in the cancer biology of hepatocellular carcinoma (HCC). We observed that linc00467 was upregulated in HCC tissues and cells. Silencing of linc00467 using small interfering RNA interference significantly inhibited the growth and motility of HCC cells, and increased cell apoptosis through regulating the Bcl-2/Bax axis and the caspase cascade, suggesting that linc00467 exerted oncogenic functions in the progression of HCC. Moreover, we found that linc00467 could target miR-18a-5p, and NEDD9 was a target for miR-18a-5p in HCC cells. Furthermore, either the miR-18a-5p inhibitor or upregulation of NEDD9 could recover the inhibitory effects caused by silencing of linc00467. In conclusion, our data highlighted the oncogenic role of linc00467 in HCC progression by regulating the miR-18a-5p/NEDD9 axis.     

Long noncoding RNA FOXD2-AS1 promotes glioma cell cycle progression and proliferation through the FOXD2-AS1/miR-31/CDK1 pathway

Long noncoding RNAs (lncRNAs) are vital mediators involved in cancer progression. Previous studies confirmed that FOXD2 adjacent opposite strand RNA 1 (FOXD2-AS1) is upregulated in tumor diseases. The potential influence of FOXD2-AS1 in glioma progression, however, remains unknown. In this paper, FOXD2-AS1 was found to be upregulated in glioma tissues. Its level was linked with glioma stage. Moreover, glioma patients expressing high level of FOXD2-AS1 suffered worse prognosis. Biological functions of FOXD2-AS1 in glioma cells were analyzed through integrative bioinformatics and TCGA RNA sequencing data analysis. Pathway enrichment analysis uncovered that FOXD2-AS1 was mainly linked with cell cycle regulation in both low-grade glioma and glioblastoma. Further experiments demonstrated that silence of FOXD2-AS1 inhibited proliferation, arrested cell cycle and downregulated cyclin-dependent kinase 1 (CDK1) in human glioma cells. Dual-luciferase reporter assay confirmed that FOXD2-AS1 upregulated CDK1 by sponging miR-31. Rescue assays were performed and confirmed the regulatory loop FOXD2-AS1/miR-31/CDK1 in glioma. Collectively, our results indicated that the FOXD2-AS1/miR-31/CDK1 axis influenced glioma progression, providing a potential new target for glioma patients.     

长链非编码RNA Linc00673过表达对胃癌MGC-803细胞增殖与凋亡的影响*

目的: 探讨长链非编码RNA Linc00673过表达对胃癌细胞增殖和凋亡的影响及其机制。方法: 将重组慢病毒表达质粒pLVX-Linc00673和对照空载体质粒pLVX-NC在293T细胞中进行慢病毒包装与扩增,将重组慢病毒转染胃癌细胞MGC-803建立稳定过表达 Linc00673的细胞系,实时荧光定量PCR方法检测Linc00673基因的表达; MTT实验和克隆形成实验观察细胞的生长增殖;流式细胞术检测细胞周期和细胞凋亡;qPCR检测细胞周期相关调控基因表达;免疫印迹法检测PI3K/Akt信号通路关键分子及肿瘤增殖相关蛋白的表达。结果: Linc00673在胃癌细胞系MGC-803、BGC-823和AGS中的表达量显著高于正常胃粘膜细胞GES-1(P＜0.05)。建立了稳定过表达Linc00673的MGC-803细胞系,Linc00673的表达量比对照空载体组高200倍。Linc00673过表达促进MGC-803细胞增殖和克隆形成(P＜0.05),抑制细胞凋亡并影响细胞周期G1→S期进程(P＜0.01);Linc00673过表达可影响MGC-803细胞周期调节基因CCNG2、p19和CDK1的表达;免疫印迹结果显示,Linc00673过表达不仅促进PI3K/Akt信号通路关键分子pAKT及其下游靶点NF-κB和Bcl-2蛋白的表达,而且上调肿瘤相关因子β-catenin和EZH2蛋白的表达。结论: Linc00673过表达可能通过PI3K/Akt信号通路促进MGC-803细胞增殖、抑制凋亡。     

Long noncoding RNA NNT-AS1 promotes gastric cancer proliferation and invasion by regulating microRNA-363 expression

Increasing studies showed that long noncoding RNAs (lncRNAs) had crucial regulatory roles in various tumors, including gastric cancer (GC). Recent studies demonstrated that lncRNA nicotinamide nucleotide transhydrogenase-antisense RNA1 (NNT-AS1) played an important role in several tumors. However, the role and expression of NNT-AS1 in GC progression remain unknown. In our study, we indicated that NNT-AS1 expression was upregulated in GC samples compared with the nontumor tissues. We also showed that NNT-AS1 expression was upregulated in the GC cell lines. Ectopic expression of NNT-AS1 promoted GC cell line HGC-27 cell proliferation, cell cycle progression, and invasion. In addition, we showed that NNT-AS1 acted as a sponge competing endogenous RNA for microRNA-363 (miR-363), which was downregulated in the GC samples and cell lines. miR-363 expression was negatively related with NNT-AS1 expression in GC samples. Upregulated expression of miR-363 suppressed GC cell growth, cycle, and invasion. Furthermore, we reported that elevated expression of NNT-AS1 promoted GC cell proliferation, cycle, and invasion partly by suppressing miR-363 expression. These results indicated that lncRNA NNT-AS1 acted as an oncogene in the development of GC partly by inhibiting miR-363 expression.     

LncRNA CASC11 promoted gastric cancer cell proliferation,migration and invasion in vitro by regulating cell cycle pathway

In this study, we aimed to investigate the effects of lncRNA CASC11 on gastric cancer (GC) cell progression through regulating miR-340-5p and cell cycle pathway. Expressions of lncRNA CASC11 in gastric cancer tissues and cell lines were determined by qRT-PCR. Differentially expressed lncRNAs, mRNAs and miRNAs were screened through microarray analysis. The relationship among CASC11, CDK1 and miR-340-5p was predicted by TargetScan and validated through dual luciferase reporter assay. Western blot assay examined the protein level of CDK1 and several cell cycle regulatory proteins. GO functional analysis and KEGG pathway analysis were used to predict the association between functions and related pathways. Cell proliferation was determined by CCK-8 assays. Cell apoptosis and cell cycle were detected by flow cytometry assay. CASC11 was highly expressed in GC tissues and cell lines. Knockdown of CASC11 inhibited GC cell proliferation, promoted cell apoptosis and blocked cell cycle. KEGG further indicated an enriched cell cycle pathway involving CDK1. QRT-PCR showed that miR-340-5p was down-regulated in GC cells tissues, while CDK1 was up-regulated. Furthermore, CASC11 acted as a sponge of miR-340-5p which directly targeted CDK1. Meanwhile, miR-340-5p overexpression promoted GC cell apoptosis and induced cell cycle arrest, while CDK1 overexpression inhibited cell apoptosis and accelerated cell cycle. Our study revealed the mechanism of CASC11/miR-340-5p/CDK1 network in GC cell line, and suggested that CASC11 was a novel facilitator that exerted a biological effect by activating the cell cycle signaling pathway. This finding provides a potential therapeutic target for GC.     

Long non-coding RNA Linc00152 is involved in cell cycle arrest,apoptosis, epithelial to mesenchymal transition,cell migration and invasion in gastric cancer

Gastric cancer remains a serious threat to public health with high incidence and mortality worldwide. Accumulating evidence demonstrates that long non-coding RNAs (lncRNAs) play important roles in regulating gene expression and are involved in various pathological processes, including gastric cancer. To investigate the possible role of dysregulated lncRNAs in gastric cancer development, we performed lncRNA microarray and identified 3141 significantly differentially expressed lncRNAs in gastric cancer tissues. Next, some of deregulated lncRNAs were validated among about 60 paired gastric cancer specimens such as Linc00261, DKFZP434K028, RPL34-AS1, H19, HOTAIR and Linc00152. Our results found that the decline of DKFZP434K028 and RPL34-AS1, and the increased expression of Linc00152 positively correlated with larger tumor size. The high expression levels of HOTAIR were associated with lymphatic metastasis and poor differentiation. Since the biological roles of Linc00152 are largely unknown in gastric cancer pathogenesis, we assessed its functions by silencing its up-regulation in gastric cancer cells. We found that Linc00152 knockdown could inhibit cell proliferation and colony formation, promote cell cycle arrest at G1 phase, trigger late apoptosis, reduce the epithelial to mesenchymal transition (EMT) program, and suppress cell migration and invasion. Taken together, we delineate the gastric cancer lncRNA signature and demonstrate the oncogenic functions of Linc00152. These findings may have implications for developing lncRNA-based biomarkers for diagnosis and therapeutics for gastric cancer.     

Upregulated long noncoding RNA Linc00261 in pre-eclampsia and its effect on trophoblast invasion and migration via regulating miR-558/TIMP4 signaling pathway

Pre-eclampsia (PE) is a leading cause of maternal and perinatal morbidity and mortality but the exact underlying mechanisms of PE pathogenesis remain elusive. Accumulated data suggested that the long noncoding RNAs (lncRNAs) play important roles in the pathogenesis of PE. The present study identified the changes of lncRNA Linc00261 in PE and its effects on trophoblasts invasion and migration. Our results showed that the expression of Linc00261 was upregulated in placental tissues of PE women compared with those of healthy pregnant women. Overexpression of Linc00261 suppressed cell invasion and migration, induced cell apoptosis, and caused cell-cycle arrest at G₀/G₁ phase of HTR-8/SVneo cells; while knockdown of Linc00261 had the opposite effects on the HTR-8/SVneo cells. Mechanistic studies showed Linc00261 functioned as a competing endogenous RNA for miR-558 in HTR-8/SVneo cells, and miR-558 was negatively regulated by Linc00261. The expression level of miR-558 in the PE group was significantly lower than the control group, and the expression level of Linc00261 was negatively correlated with the expression level of miR-558 in the placental tissues of women with PE. Furthermore, miR-558 was found to negatively regulate the expression of TIMP metallopeptidase inhibitor 4 (TIMP4) via targeting the 3′ untranslated region in the HTR-8/SVneo cells. Overexpression of miR-558 increased HTR-8/SVneo cell invasion and migration, which was attenuated by TIMP4 overexpression. More importantly, both overexpression of miR-558 and knockdown of TIMP4 partially reversed the suppressive effects of Linc00261 overexpression on cell invasion and migration of HTR-8/SVneo cells. Collectively, our results for the first time showed the upregulation of Linc00261 in the placental tissues of severe PE patients. The mechanistic results indicated that Linc00261 exerted the suppressive effects on the trophoblast invasion and migration via targeting miR-558/TIMP4 axis, which may involve in the pathogenesis of PE.     

circ_ARF3 regulates the pathogenesis of osteosarcoma by sponging miR-1299 to maintain CDK6 expression

Increasing evidence suggests that circular RNAs are emerging biomarkers or targets for early cancer diagnosis and treatment. However, the studies of circular RNA in osteosarcoma (OS) are limited. In this study we found that circ_ARF3 were highly expressed in osteosarcoma cell lines and tumor tissues. Knocking down circ_ARF3 greatly ceased OS cell growth, impaired cell colony formation and halted cell cycle transition from G1 to S phase. Bioinformatic analysis suggested that miR-1299 is the target of circ_ARF3. Luciferase assay and biotin labeled circ_ARF3 pull down assay confirmed their interactions in OS cells. The regulatory roles of circ_ARF3 on miR-1299 was also investigated. Further bioinformatic analysis showed that CDK6 is the target of miR-1299. Overexpressing miR-1299 in OS cells decreased CDK6 expression and arrested OS cell growth and cell cycle progression. However, the roles of miR-1299 in regulating CDK6 expression, OS cell growth and cell cycle progression were greatly impaired in the presence of circ_ARF3. In general, our study demonstrated that in the OS, highly expressed circ_ARF3 acts as a sponge of miR-1299 to inhibit miR-1299 mediated CDK6 downregulation which further promoted OS pathogenesis. circ_ARF3 could be a potential target for OS treatment in the future.     

Growth inhibitory effects of three miR-129 family members on gastric cancer

Reduced expression of microRNA-129 (miR-129) has been reported in several types of tumor cell lines as well as in primary tumor tissues. However, little is known about how miR-129 affects cell proliferation in gastric cancer. Here, we show that all miR-129 family members, miR-129-1-3p, miR-129-2-3p, and miR-129-5p, are down-regulated in gastric cancer cell lines compared with normal gastric epithelial cells. Furthermore, using the real-time cell analyzer assay to observe the growth effects of miR-129 on gastric cancer cells, we found that all three mature products of miR-129 showed tumor suppressor activities. To elucidate the molecular mechanisms underlying down-regulation of miR-129 in gastric cancer, we analyzed the effects of miR-129 mimics on the cell cycle. We found that increased miR-129 levels in gastric cancer cells resulted in significant G₀/G₁ phase arrest. Interestingly, we showed that cyclin dependent kinase 6 (CDK6), a cell cycle-associated protein involved in G₁-S transition, was a target of miR-129. We also found that expression of the sex determining region Y-box 4 (SOX4) was inversely associated with that of miR-129-2-3p and miR-129-5p but not of miR-129-1-3p. Together, our data indicate that all miR-129 family members, not only miR-129-5p, as previously thought, play an important role in regulating cell proliferation in gastric cancer.     

miR-155 通过p53/p21 调控前列腺癌细胞周期

目的:探讨miR-155对前列腺癌细胞周期的影响及其分子机制。方法:通过转染anti-miR-155抑制前列腺癌DU145和PC-3细胞中miR-155水平后,采用流式细胞术观察细胞周期的变化,western blot和RT-PCR观察p53和p21蛋白及CDK2和cyclin蛋白和m RNA表达的变化。结果:与对照组相比,DU145和PC-3细胞转染anti-miR-155后,G2/M期细胞阻滞,S期细胞数比例显著增加(P0.05),p53和p21蛋白和m RNA表达水平显著增加(P0.01),CDK2和cyclin E蛋白和m RNA表达均显著降低(P0.01)。结论:miR-155可影响人前列腺癌细胞的周期,可能与其调节p53、p21及其下游的CDK2和cyclin E的表达相关。     

MiR-23a-3p promoted G1/S cell cycle transition by targeting protocadherin17 in hepatocellular carcinoma

MiR-23a-3p has been shown to promote liver cancer cell growth and metastasis and regulate that of chemosensitivity. Protocadherin17 (PCDH17) is a tumor suppressor gene and plays an essential part in cell cycle of hepatocellular carcinoma (HCC). This study aimed at evaluating the effects of miR-23a-3p and PCDH17 on HCC cell cycle and underlining the mechanism. The level of miR-23a-3p was up-regulated, while PCDH17 level was down-regulated in HCC tissues compared to adjacent tissues. For the in vitro studies, high expression of miR-23a-3p down-regulated PCDH17 level; increased cell viability; promoted G1/S cell cycle transition; up-regulated cyclin D1, cyclin E, CDK2, CDK4, p-p27, and p-RB levels; and down-regulated the expression of p27. Dual luciferase reporter assay suggested PCDH17 was a target gene of miR-23a-3p. MiR-23a-3p inhibitor and PCDH17 siRNA led to an increase in cell viability and the number of cells in the S phase and up-regulated cyclin D1 and cyclin E levels, compared with miR-23a-3p inhibitor and NC siRNA group. For the in vivo experiments, high expression of miR-23a-3p promoted tumor growth and reduced PCDH17 level in the cytoplasm. These results indicated that high expression of miR-23a-3p might promote G1/S cell cycle transition by targeting PCDH17 in HCC cells. The miR-23a-3p could be considered as a molecular target for HCC detection.