MiR-125a regulates ovarian cancer proliferation and invasion by repressing GALNT14 expression

Increasing evidence has suggested that dysregulation of microRNAs (miRNAs) could contribute to tumor progression. The miR-125a was downregulated in several types of cancer, however, the molecular mechanism of miR-125a in the ovarian cancer remains unclear. The aim of the paper was to reveal the mechanism of miR-125a regulating cell proliferation and metastasis in ovarian cancer. In this study, western blotting, immunohistochemistry and serum-ELISA assay revealed that polypeptide N-acetylgalactosaminyl transferase 14 (GALNT14) expression was upregulated and correlated with the cancer stage in ovarian cancer. The expression levels of miR-125a were downregulated and negatively related to GALNT14 expression in clinical ovarian cancer tissues. Moreover, luciferase reporter assay identified polypeptide N-acetylgalactosaminyl transferase 14 (GALNT14) as a direct target of miR-125a, and overexpression of miR-125a markedly reduced the expression of GALNT14 in ovarian cancer. Functional characterization of miR-125a was accomplished by reconstitution of miR-125a and silencing GALNT14 expression in ovarian cancer cells to determine changes in proliferation and invasion. The MTT assay and transwell assay revealed that miR-125a transfectant significantly inhibits cell proliferation and invasion, by repressing GALNT14 expression. Furthermore, the gelatin zymography assay miR-125a mimics and GALNT14 siRNA suppressed the activity of MMP2 and MMP9. Taken together, our findings show that miR-125a functions as tumor suppressor in ovarian cancer by targeting GALNT14, and miR-125a may therefore serve as a biomarker for diagnosis and therapeutics in ovarian cancer.     

miR-99a promotes proliferation targeting FGFR3 in human epithelial ovarian cancer cells

MiRNAs have been reported as important regulators in normal physiological processes, human cancer, and even their roles as therapeutic targets have been proposed. In epithelial ovarian cancer (EOC), the expression of miRNAs is reported to remarkably deregulate, showing that miRNAs are involved in the initiation and progression of this disease. In this study, we found that miR-99a was obviously decreased in EOC tissues, serums and cell lines SKOV-3. Importantly, fibroblast growth factor receptor 3 (FGFR₃), predicted to be one target gene of miR-99a using computational algorithms, was higher in expression in EOC cells. Subsequently, FGFR₃ was proved to be direct target of miR-99a by dual luciferase assay. Furthermore, overexpression of miR-99a dramatically suppressed expression level of FGFR₃ at both mRNA and protein levels, proving FGFR₃ to be inversely correlated with miR-99a. Finally, overexpression of miR-99a could significantly inhibit EOC cell proliferation in vitro by decreasing the expression of FGFR₃ which also reduced the EOC cell growth after siRNA knockdown. Conclusively, miR-99a expression was remarkably downregulated in serums, tissues and cell and suppresses EOC cell proliferation by targeting FGFR₃, suggesting miR-99a as a prospective prognosis marker and potential tumor suppressor for EOC therapeutics.     

miR-601 is a prognostic marker and suppresses cell growth and invasion by targeting PTP4A1 in breast cancer

MicroRNAs (miRNA) play important roles in the initiation and progression of breast cancer. Here, we investigated the role of miR-601 in breast cancer and found that its expression was significantly down-regulated in breast cancer tissues compared with matched adjacent non-cancerous breast tissues. Moreover, we found that down-regulation of miR-601 was closely associated with distant metastasis and poor distant metastasis-free survival in breast cancer. In addition, miR-601 levels were inversely correlated with metastatic potential of human breast cancer cell lines. Further experiments showed that ectopic overexpression of miR-601 suppressed breast cancer cell proliferation, migration and invasion, whereas miR-601 knockdown promoted breast cancer cell proliferation, migration and invasion. Furthermore, protein tyrosine phosphatase type IVA 1 (PTP4A1) was identified as a direct target of miR-601. Overexpression of miR-601 repressed PTP4A1 mRNA and protein expression. Conversely, inhibition of miR-601 increased PTP4A1 mRNA and protein expression. Taken together, our data suggest that miR-601 inhibits growth and invasion of breast cancer cells by targeting PTP4A1 and that miR-601 is a potential biomarker for prognosis and therapeutic target in breast cancer.     

CircHIPK3 regulates melanoma cell behaviors by binding with miR-215–5p to upregulate YY1

ObjectTo investigate the role of circHIPK3 in melanoma.MethodsBioinformatics analysis and experiments including RT-qPCR, Pearson's correlation analysis, luciferase reporter, Western blot, and RIP assays were applied to explore the function and mechanism of circHIPK3 in melanoma.ResultsCircHIPK3 expression was strikingly upregulated while miR-215–5p was downregulated in melanoma tissues and cell lines. Pearson's correlation analysis unveiled circHIPK3 expression was positively correlated with Ki-67 (a marker of proliferation), which implied that circHIPK3 may play a vital role in the progression of melanoma. In mechanism, luciferase reporter and RIP assays validated that circHIPK3 was able to bind with miR-215–5p. Moreover, we confirmed that overexpression of circHIPK3 could facilitate cell proliferation and depress cell apoptosis in melanoma while overexpression of miR-215–5p exerted opposite effects. Besides, our findings indicated that miR-215–5p overexpression significantly reversed the circHIPK3 overexpressing-mediated promotive effect on cell proliferation and inhibitory effect on cell apoptosis. Furthermore, we found that miR-215–5p could directly target YY1. Upregulation of YY1 could notably offset the inhibitory effect of circHIPK3 downregulation on cell proliferation and the promotive effect on cell apoptosis.ConclusionOur study corroborated that circHIPK3 regulated melanoma cell behaviors via the miR-215–5p/YY1 axis, which might provide a novel insight for the treatment of melanoma patients.     

The micro RNA hsa-miR-377-3p inhibits tumor growth in malignant melanoma

Background/Aims: Most recently, micro RNAs (miRNAs/miRs) have been suggested to play a key role in various physiological and pathological processes by regulating the expression of specific genes. The influence of miR-377-3p on multitudinous cancer cells has been investigated; however, its function in melanoma remains undiscovered. Armadillo repeat-containing protein 8 (ARMC8), a target of miR-377-3p, plays essential roles in proliferation, differentiation and apoptosis. Our research aimed to detect the specific roles of miR-377-3p in melanoma. Methods: The MiRNA and mRNA expressions were evaluated by a real-time quantitative polymerase chain reaction in the A375 and HEMa-LP cell lines. We predicted the possible interactions between microRNA and mRNAs by bioinformatics database and constructed them with the Cytoscape software. The proliferation and migration activities were investigated using a cell counting kit-8 (CCK8) and wound-healing assay. Validation of the correlation between miR-377-3p and ARMC8 was implemented by the luciferase reporter assay and PCR. Results: The expression of miR-377-3p was found to be lower in malignant melanoma cells. The upregulation of miR-377-3p inhibited the melanoma cell proliferation, migration, and ARMC8 expression. miR-377-3p was identified to bind to the 3′UTR region of ARMC8 directly; this indicated that miR-377-3p suppressed melanoma cell growth partly mediated via the ARMC8 expression. Conclusion: These findings show that miR-377-3p negatively regulates tumor growth in malignant melanoma, which may thus provide a potential biological target for melanoma treatment and subsequently lead to the development of potential treatments.

We have demonstrated that miR-377-3p inhibits melanoma cell growth by binding to the ARMC8 mRNA in the A375 cell line.     

MiR-595 targeting regulation of SOX7 expression promoted cell proliferation of human glioblastoma

Increasing evidence indicated that dysregulation of microRNAs (miRNAs) were involved with human disease including cancer. Recently, miR-595 was reported as a tumor promoter in malignant mesothelioma. However, the underlying mechanism of miR-595 in human glioblastoma (GBM) cells have not been well elucidated. Therefore, in this study, we investigated the biological functions and molecular mechanisms of miR-595 in human GBM. MiR-595 expression was significantly upregulated in GBM tissues and cells. We modified miR-595 levels in GBM cells and investigated their effects on the cell proliferation by MTT, colony formation and anchorage-independent growth assays. We found that miR-595 significantly increased GBM cell proliferation. Bioinformatic analysis predicted that miR-595 may target the 3′-UTR of SOX7and suppressed its translation, and further confirmed by luciferase assay. In sum, these observations together indicated that miR-595 played a critical role in carcinogenesis by suppression of SOX7, and may serve as a therapeutic target for the treatment of GBM.     

miR-663a inhibits hepatocellular carcinoma cell proliferation and invasion by targeting HMGA2

Hepatocellular carcinoma (HCC) is a highly aggressive solid malignancy throughout the world. Dysregulation of miRNAs play essential roles in HCC progression via aberrant regulation of cell proliferation, apoptosis, as well as metastasis. miR-663a is a poorly investigated miRNA. Whether miR-663a regulates HCC development remains unknown. The aim of the study was to explore the role of miR-663a in HCC development. To determine the expression level of miR-663a in HCC, we analyzed the data from GSE21362 and TCGA. The results showed that miR-663a was significantly down-regulated in HCC tissue compared with adjacent non-tumor tissue. Gain of function and loss of function assays revealed that miR-663a distinctly inhibited cell proliferation, migration and invasion. Mechanistic investigations demonstrated that miR-663a modulated cell functions through targeting and suppressing high mobility group A2 (HMGA2). In addition, overexpression of HMGA2 remarkably attenuated the tumor repressive effect of miR-663a. Taken together, miR-663a inhibits HCC cell proliferation and motility by targeting HMGA2.     

Therapeutic Effects of MicroRNA-582-5p and -3p on the Inhibition of Bladder Cancer Progression

Many reports have indicated that the abnormal expression of microRNAs (miRNAs) is associated with the progression of disease and have identified miRNAs as attractive targets for therapeutic intervention. However, the bifunctional mechanisms of miRNA guide and passenger strands in RNA interference (RNAi) therapy have not yet been clarified. Here, we show that miRNA (miR)-582-5p and -3p, which are strongly decreased in high-grade bladder cancer clinical samples, regulate tumor progression in vitro and in vivo. Significantly, the overexpression of miR-582-5p or -3p reduced the proliferation and invasion of UM-UC-3 human bladder cancer cells. Furthermore, transurethral injections of synthetic miR-582 molecule suppressed tumor growth and metastasis in an animal model of bladder cancer. Most interestingly, our study revealed that both strands of miR-582-5p and -3p suppressed the expression of the same set of target genes such as protein geranylgeranyltransferase type I beta subunit (PGGT1B), leucine-rich repeat kinase 2 (LRRK2) and DIX domain containing 1 (DIXDC1). Knockdown of these genes using small interfering RNA (siRNA) resulted in the inhibition of cell growth and invasiveness of UM-UC-3. These findings uncover the unique regulatory pathway involving tumor suppression by both strands of a single miRNA that is a potential therapeutic target in the treatment of invasive bladder cancer.     

Retracted Article: Knockdown of long non-coding RNA OIP5-AS1 suppresses cell proliferation and migration in ox-LDL-induced human vascular smooth muscle cells (hVMSCs) through targeting miR-152-3p/PAPPA axis

Emerging evidence has demonstrated that long non-coding RNA Opa-interacting protein 5 antisense RNA 1 (OIP5-AS1) is associated with cellular behaviors among malignant tumors. However, the role of OIP5-AS1 in atherosclerosis remains largely undefined. The aim of this study was to explore the expression and role of OIP5-AS1 in a cell model of atherosclerosis, as well as the underlying mechanism. We found that expression of OIP5-AS1 was upregulated in human vascular smooth muscle cells (hVMSCs) under oxidized low density lipoprotein (ox-LDL) administration, and knockdown of OIP5-AS1 suppressed cell viability (CCK-8) and proliferating cell nuclear antigen (PCNA) protein level in ox-LDL-treated hVMSCs, as well as inhibited cell migration rate (wound healing assay) and protein expression of matrix metalloproteinase (MMP)-2 and MMP-9. Mechanically, OIP5-AS1 functioned as competing endogenous RNA (ceRNA) to positively regulate PAPPA expression through sponging miRNA-152-3p (miR-152), and pregnancy-associated plasma protein A (PAPPA) was identified as a downstream target gene for miR-152. Moreover, expression of miR-152 was downregulated and PAPPA was upregulated in ox-LDL-treated hVMSCs. Similarly to OIP5-AS1 knockdown, miR-215 overexpression could inhibit cell proliferation and migration of hVMSCs administrated by ox-LDL, which was abated by PAPPA upregulation. Moreover, miR-215 downregulation partially reversed the suppressive role of OIP5-AS1 knockdown as well. In conclusion, knockdown of OIP5-AS1 suppressed ox-LDL-treated hVMSC proliferation and migration presumably through targeting miR-152/PAPPA axis, suggesting a novel OIP5-AS1/miR-152/PAPPA pathway in atherogenesis.

Knockdown of OIP5-AS1 suppressed ox-LDL-treated hVMSCs proliferation and migration; overexpression of miR-152 played the similar role of OIP5-AS1 knockdown; OIP5-AS1 functioned as ceRNA to regulate PAPPA expression through sponging miR-152.     

miR-505-3p 对胃癌细胞增殖、克隆形成及迁移、侵袭的影响及机制研究

目的 检测胃癌组织及细胞中miR-505-3p 表达,并探究其对胃癌细胞增殖、克隆形成、迁移和侵袭的影响及潜在分子机制。方法 利用实时荧光定量PCR 实验（qRT-PCR）检测胃癌组织、癌旁正常组织及胃癌细胞和人正常胃黏膜细胞中miR-505-3p 相对表达;构建miR-505-3p 过表达、c-MYC 过表达和敲低表达细胞系,通过CCK-8 法,克隆斑点形成实验、Transwell 侵袭/ 迁移实验检测miR-505-3p 和c-MYC 对胃癌细胞增殖、克隆形成及迁移、侵袭的影响;裸鼠皮下成瘤实验验证miR-505-3p 对裸鼠肿瘤生长的影响;双荧光素报告实验验证miR-505-3p 和c-MYC 的靶向关系,并探究其两者间的表达调控作用;Western blot 检测miR-505-3p 和c-MYC 对Wnt/β-catenin 通路关键蛋白表达的影响。结果 临床胃癌组织中miR-505-3p 表达水平较正常癌旁组织显著下调（0.92±0.37 vs 1.74±0.59）,差异有统计学意义（t=3.723,P ＜ 0.01）。胃癌细胞系MGC803（1.12±0.35）,AZ521（2.31±0.24）和HGC-27（2.28±0.43）中miR-505-3p 相对表达较人正常胃黏膜细胞系GES1（4.62±0.79）明显降低,差异有统计学意义（F=26.109,P ＜ 0.001）。miR-505-3p 过表达组细胞增殖（0.92±0.27）、克隆形成（51.67±21.75）、迁移（43.25±15.47 ）、侵袭（38.53±14.76）能力较NC组（1.85±0.34,128.36±36.42,100.08±2.12,100.12±1.94）明显降低,差异均有统计学意义（t=3.131 ～ 7.166,均P ＜ 0.05）;miR-505-3p 过表达抑制了裸鼠生长。c-MYC 是miR-505-3p 的靶基因,miR-505-3p 靶向负调控c-MYC。c-MYC 过表达组细胞增殖（2.72±0.68）、迁移（147.15±20.36）、侵袭（145.46±22.73）能力较NC 组（1.85±0.34,100.08±2.12,100.12±1.94）明显增高,差异均有统计学意义（t=2.455 ～ 4.456,均P ＜ 0.05）;c-MYC 过表达可逆转miR-505-3p 对胃癌细胞增殖、迁移和侵袭的抑制作用。miR-505-3p 过表达组Wnt（0.46±0.07 ）,β-catenin（0.50±0.05）蛋白相对表达水平明显低于NC 组（1.01±0.02,1.02±0.02）,差异均有统计学意义（t=8.139,7.342,均P ＜ 0.001）;过表达c-MYC 能够逆转miR-505-3p 对Wnt 和β-catenin 蛋白表达的抑制作用。结论 胃癌中miR-505-3p 显著低表达,其可通过靶向调控c-MYC 表达介导Wnt/β-catenin 信号通路激活进而发挥作用参与胃癌的发生发展过程。     

Tumor suppressor miR-449a inhibits the development of gastric cancer via down-regulation of SGPL1

MicroRNAs (miRNAs) are small noncoding RNAs that are known to participate in the regulation of many physiological and pathological processes, which can indirectly influence the development of malignant behaviors. Numerous studies have demonstrated that miR-449a plays important roles in human carcinogenesis. However, its precise functional and regulatory roles remain unclear. In this study, we mainly explored the functional role of miR-449a in gastric cancer (GC). The expression levels of miR-449a in 98 cases of GC tissues and cell lines were determined by qRT-PCR. The possible mechanisms of miR-449a in GC cells were explored by fluorescence reporter assay. miR-449a expression was significantly lower in GC tissues compared to matched para-carcinoma tissues and was associated with tumor differentiation. Furthermore, in vitro knockdown of miR-449a by siRNA significantly inhibited MKN-28 cell proliferation, migration and invasion as well as tumorigenesis via inducing G0/G1 arrest of GC cells. In addition, we identified SGPL1 as a target of miR-449a and demonstrated that miR-449a regulated SGPL1 expression via binding its 3′-UTR region. The experiments indicated that miR-449a functions as a novel tumor suppressor in GC and its anti-oncogenic activity may involve its inhibition of the target gene SGPL1. These findings suggested that miR-449a may be a promising candidate for the development of antitumor drugs targeting GC.

MicroRNAs (miRNAs) are small noncoding RNAs that are known to participate in the regulation of many physiological and pathological processes, which can indirectly influence the development of malignant behaviors.     

Caprin-1 is a novel microRNA-223 target for regulating the proliferation and invasion of human breast cancer cells

MicroRNAs (miRNAs) are 21–22 nucleotides regulatory small non-coding RNAs that inhibit gene expression by binding to complementary sequences especially the 3’ untranslated region (3’UTR) of mRNA. One miRNA can target many messenger RNAs, leading to a complex metabolic network. Previous studies have shown that miRNA-223 regulates migration and invasion of tumor cells and targets cytoplasmic activation/proliferation-associated protein-1 (Caprin-1). In the present study, we detected the expression of miRNA-223 and Caprin-1 in MCF-7, T-47D and MDA-MB-231 cancer cell lines, and MCF-10A normal breast cell line, and analyzed the role of miRNA-223 in Caprin-1-induced proliferation and invasion of human breast cancer cells. We found that miRNA-223 expression levels are significantly lower in MCF-7, T-47D and MDA-MB-231 cancer cells than in MCF-10A normal breast cells, while Caprin-1 expression is higher in cancer cells than in normal breast cells. The most malignant cancer cell line MDA-MB-231 has the lowest expression of miR-223, but the highest expression of Caprin-1. Further, we found that miR-223 targets the 3’UTR of Caprin-1 miRNA and down-regulates the expression of Caprin-1. We also found that over-expression of Caprin-1 can promote the proliferation and the invasion of breast cancer cells, but miRNA-223 can inhibit the proliferation and the invasion. miRNA-223-induced inhibition can be reversed by ectopic over-expression of Caprin-1. These findings suggest that miR-223 may suppress the proliferation and invasion of cancer cells by directly targeting Caprin-1. Our study also indicates that expression levels of miR-223 and Caprin-1 can be used to predict the state of cancer in breast cancer patient.     

miR-935 promotes gastric cancer cell proliferation by targeting SOX7

Gastric cancer is the most common cancer in the world, miRNAs have been demonstrated to play critical role in the development and progression of gastric cancer, such as miR-7, miR-217 and miR-335. Here, we found miR-935 was upregulated in gastric cancer tissues and cells. Overexpression of miR-935 promoted cell proliferation and tumorigenesis in vitro determined by MTT analysis, colony formation analysis, BrdU cell proliferation analysis and soft agar growth analysis, knockdown of miR-935 reduced these effects. Tumor suppressor sex-determining region Y-box 7 (SOX7) was the direct target of miR-935, overexpression of miR-935 inhibited SOX7 expression, but promoted the levels CCND1 and C-MYC which promotes cell proliferation and tumorigenesis, knockdown of miR-935 increased SOX7 level, and inhibited CCND1 and C-MYC expression. Synchronous knockdown of miR-935 and SOX7 promoted cell proliferation and tumorigenesis in vitro, confirming miR-935 regulated gastric cancer cell proliferation by inhibiting SOX7. In summary, we found miR-935 contributed to cell proliferation of gastric cancer through targeting SOX7.     

KITENIN-targeting MicroRNA-124 Suppresses Colorectal Cancer Cell Motility and Tumorigenesis

MicroRNAs are increasingly implicated in the modulation of the progression of various cancers. We previously observed that KAI1 C-terminal interacting tetraspanin (KITENIN) is highly expressed in sporadic human colorectal cancer (CRC) tissues and hence the functional KITENIN complex acts to promote progression of CRC. However, it remains unknown that microRNAs target KITENIN and whether KITENIN-targeting microRNAs modulate CRC cell motility and colorectal tumorigenesis. Here, through bioinformatic analyses and functional studies, we showed that miR-124, miR-27a, and miR-30b negatively regulate KITENIN expression and suppress the migration and invasion of several CRC cell lines via modulation of KITENIN expression. Through in vitro and in vivo induction of mature microRNAs using a tetracycline-inducible system, miR-124 was found to effectively inhibit the invasion of CT-26 colon adenocarcinoma cells and tumor growth in a syngeneic mouse xenograft model. Constitutive overexpression of precursor miR-124 in CT-26 cells suppressed in vivo tumorigenicity and resulted in decreased expression of KITENIN as well as that of MYH9 and SOX9, which are targets of miR-124. Thus, our findings identify that KITENIN-targeting miR-124, miR-27a, and miR-30b function as endogenous inhibitors of CRC cell motility and demonstrate that miR-124 among KITENIN-targeting microRNAs plays a suppressor role in colorectal tumorigenesis.     

miR-425 inhibits melanoma metastasis through repression of PI3K-Akt pathway by targeting IGF-1

miR-425 is a potential tumor suppressor in cancer, but its role in melanoma is still unknown. We aim to investigate miR-425 expression in melanoma tissues and cell lines. Next, cell proliferation, cell cycle, apoptosis and metastasis will be studied using lentivirus-mediated gain-of-function studies. The predicted results are stable miR-425 inhibits cell proliferation and metastasis and induced cell apoptosis. It is predicted that IGF-1 is a potential target gene of miR-495 by bioinformatics analysis. Then luciferase assay analysis identifies IGF-1 as a new direct target gene of miR-425 and miR-425 inhibits melanoma cancer progression via IGF-1. Collectively, our findings suggested that miR-425 may function as a tumor suppressor in melanoma by targeting IGF-1.