MicroRNA-335 suppresses the proliferation,migration, and invasion of breast cancer cells by targeting EphA4

MicroRNAs (miRNAs) are small noncoding RNAs that exert their functions by targeting specific mRNA sequences. Many studies have demonstrated that miRNAs are crucial for cancer progression, during which they can act as either oncogenes or tumor suppressors. Previous research has shown that miR-335 is downregulated in breast cancer, and it has been shown to be a breast cancer suppressor. In addition, emerging evidence indicates that erythropoietin-producing hepatocellular A4 (EphA4) is implicated in cancer cell proliferation, migration, and invasion. However, little is known about the relationship between miR-335 and EphA4 in breast cancer. In the present study, we used bioinformatic and biochemical analyses to demonstrate that EphA4 is a direct downstream target of miR-335 in human breast cancer MCF-7 and MDA-MB-23 cells and revealed that miR-335 negatively regulates the expression of EphA4 in these cells. Further investigation revealed that miR-335 overexpression inhibits MCF-7 and MDA-MB-231 cell proliferation and that this inhibition is attenuated by EphA4 coexpression. Similarly, miR-335 overexpression also inhibited growth and downregulated EphA4 expression in tumors in nude mice. Moreover, our results demonstrated that miR-335 overexpression suppresses migration and invasion in MCF-7 and MDA-MB-231 cells, an effect that was reversed by EphA4 overexpression. These findings confirmed that EphA4 is a direct target gene of miR-335 and that miR-335 suppresses breast cancer cell proliferation and motility in part by directly inhibiting EphA4 expression.     

Retracted: MicroRNA-204-3p represses colon cancer cells proliferation,migration, and invasion by targeting HMGA2

Colon cancer is a detrimental neoplasm of the digestive tract. MicroRNAs (miRNAs) as central regulators have been discovered in colon cancer. Nonetheless, the impact of miR-204-3p on colon cancer remains indistinct. The research attempted to uncover the impacts of miR-204-3p on colon cancer cells growth, migration, and invasion. miR-204-3p expression level in colon cancer tissues and diverse colon cancer cell lines were testified by the quantitative real-time polymerase chain reaction. Exploration of the impacts of miR-204-3p on cell growth, migration, invasion, and their associated factors through assessment of CCK-8, flow cytometry, Transwell, and western blot, respectively. High mobility group AT-hook 2 (HMGA2) expression was then detected in Caco-2 cells after miR-204-3p mimic and inhibitor transfection, additionally dual-luciferase activity was implemented to further uncover the correlation between HMGA2 and miR-204-3p. The impact of HMGA2 on Caco-2 cell growth, migration, and invasion was finally assessed. We found that repression of miR-204-3p was discovered in colon cancer tissues and HCT116, SW480, Caco-2, HT29 and SW620 cell lines. MiR-204-3p overexpression mitigated Coca-2 cell viability, facilitated apoptosis, simultaneously adjusted CyclinD1 and cleaved caspase-3 expression. Cell migration, invasion, and the associated factors were all suppressed by miR-204-3p overexpression. Reduction of HMGA2 was presented in Caco-2 cells with miR-204-3p mimic transfection, and HMGA2 was predicated to be a target gene of miR-204-3p. Besides, HMGA2 silence showed the inhibitory effect on Caco-2 cells growth, migration, and invasion. In conclusion, miR-204-3p repressed colon cancer cell growth, migration, and invasion through targeting HMGA2.     

MicroRNA-140 inhibit prostate cancer cell invasion and migration by targeting YES proto-oncogene 1

Prostate cancer (PCa), which is an aggressive malignancy of the male genitourinary system. In the present study, the effects of microRNA-140 (miR-140) on PCa were determined. We transfected miR-140 mimics or negative control into PCa cells, and we used MTT, wound healing, and Transwell assays for determining the capacities of miR-140 in cell proliferation, migration, and invasion, respectively. We also confirmed the relationship between miR-140 and YES proto-oncogene 1 (YES1) using Luciferase reporter assay. The results showed that miR-140 was downregulated in PCa cells and tissues, and overexpression of miR-140 could significantly suppress their capacities of proliferation, migration, and invasion. Moreover, YES1 was shown to be a direct target of miR-140. Moreover, miR-140 expression is negatively correlated with YES1 levels. miR-140 exhibits significant tumor-suppressive effects in PCa by inhibiting YES1. The study indicated that miR-140 and YES1 could be the potential targets for PCa therapy.     

MicroRNA-409-3p inhibits migration and invasion of bladder cancer cells via targeting c-Met

There is increasing evidence suggesting that dysregulation of certain microRNAs (miRNAs) may contribute to tumor progression and metastasis. Previous studies have shown that miR-409-3p is dysregulated in some malignancies, but its role in bladder cancer is still unknown. Here, we find that miR-409-3p is down-regulated in human bladder cancer tissues and cell lines. Enforced expression of miR-409-3p in bladder cancer cells significantly reduced their migration and invasion without affecting cell viability. Bioinformatics analysis identified the pro-metastatic gene c-Met as a potential miR-409-3p target. Further studies indicated that miR-409-3p suppressed the expression of c-Met by binding to its 3′-untranslated region. Silencing of c-Met by small interfering RNAs phenocopied the effects of miR-409-3p overexpression, whereas restoration of c-Met in bladder cancer cells bladder cancer cells overexpressing miR-409-3p, partially reversed the suppressive effects of miR-409-3p. We further showed that MMP2 and MMP9 may be downstream effector proteins of miR-409-3p. These findings indicate that miR-409-3p could be a potential tumor suppressor in bladder cancer.     

MicroRNA-630 inhibits breast cancer progression by directly targeting BMI1

MicroRNAs (miRNAs) play critical roles in breast cancer cell biological processes, including proliferation and apoptosis by inhibiting the expression of their target genes. Herein, we reported that miR-630 overexpression initiates apoptosis, blocks cell cycle progression and suppresses cell proliferation in breast cancer cells. Furthermore, BMI1, a member of polycomb group family, was identified as a direct target of miR-630, and there was a negative correlation between the expression levels of BMI1 and miR-630 in human breast cancer samples. With a series of biology approaches, subsequently, we proved that BMI1 was a functional downstream target of miR-630 and mediated the property of miR-630-dependent inhibition of breast cancer progression. Taken together, these findings provide further evidence on the tumor-suppression function of miR-630 in breast cancer, and clarify BMI1 as a novel functional target gene of miR-630.     

MicroRNA-215 enhances invasion and migration by targeting retinoblastoma tumor suppressor gene 1 in high-grade glioma

Objective

To elucidate the molecular mechanism of microRNA-215 (miR-215) in the migration and invasion of high grade glioma.

Results

42 Patients were analysed for clinicopathological characteristics. qRT-PCR showed that miR-215 was up-regulated in glioma tissues compared with non-neoplastic brain tissues (P < 0.05). The up-regulated miR-215 was closely associated with high grade glioma (P < 0.01) and poor overall survival (P < 0.01). Transwell assay showed that re-expression of miR-215 enhanced migration and invasion of glioma cells. miR-215 also down-regulated retinoblastoma tumor suppressor gene 1 (RB1) expression by targeting its 3′-UTR. Reversely, re-expression of RB1 inhibited partial effect of miR-215 on migration and invasion in vitro.

Conclusions

Re-expression of miR-215 promoted cell migration and invasion of glioma by targeting RB1. miR-215 can thus be used as a biomarker for tumor progression and prognosis in human high grade glioma.

     

MicroRNA-106b in cancer-associated fibroblasts from gastric cancer promotes cell migration and invasion by targeting PTEN

It is well established that the interaction between cancer cells and microenvironment has a critical role in tumor development, but the roles of miRNAs in this interaction are rarely known. Here, we have shown that miR-106b is up-regulated in cancer associated fibroblasts compared with normal fibroblasts established from patients with gastric cancer, the expression level of miR-106b is associated with poor prognosis of patients, and CAFs with down-regulated miR-106b could significantly inhibit gastric cancer cell migration and invasion by targeting PTEN. Taken together, these data suggest that miR-106b might be a novel candidate target for the treatment of gastric cancer.     

MicroRNA-196a promotes renal cancer cell migration and invasion by targeting BRAM1 to regulate SMAD and MAPK signaling pathways

Rationale: MicroRNAs (miRNAs) are endogenous ~22nt RNAs that play critical regulatory roles in various biological and pathological processes, including various cancers. Their function in renal cancer has not been fully elucidated. It has been reported that miR-196a can act as oncogenes or as tumor suppressors depending on their target genes. However, the molecular target for miR-196a and the underlying mechanism in miR-196a promoted cell migration and invasion in renal cancer is still not clear.Methods: The expression, survival and correlation between miR-196a and BRAM1 were investigated using TCGA analysis and validated by RT-PCR and western blot. To visualize the effect of Bram1 on tumor metastasis in vivo, NOD-SCID gamma (NSG) mice were intravenously injected with RCC4 cells (10⁶ cells/mouse) or RCC4 overexpressing Bram1. In addition, cell proliferation assays, migration and invasion assays were performed to examine the role of miR-196a in renal cells in vitro. Furthermore, immunoprecipitation was done to explore the binding targets of Bram1.Results: TCGA gene expression data from renal clear cell carcinoma patients showed a lower level of Bram1 expression in patients'' specimens compared to adjacent normal tissues. Moreover, Kaplan‑Meier survival data clearly show that high expression of Bram1correlates to poor prognosis in renal carcinoma patients. Our mouse metastasis model confirmed that Bram1 overexpression resulted in an inhibition in tumor metastasis. Target-prediction analysis and dual-luciferase reporter assay demonstrated that Bram1 is a direct target of miR-196a in renal cells. Further, our in vitro functional assays revealed that miR-196a promotes renal cell proliferation, migration, and invasion. Rescue of Bram1 expression reversed miR-196a-induced cell migration. MiR-196a promotes renal cancer cell migration by directly targeting Bram1 and inhibits Smad1/5/8 phosphorylation and MAPK pathways through BMPR1A and EGFR.Conclusions: Our findings thus provide a new mechanism on the oncogenic role of miR-196a and the tumor-suppressive role of Bram1 in renal cancer cells. Dysregulated miR-196a and Bram1 represent potential prognostic biomarkers and may have therapeutic applications in renal cancer.     

MicroRNA-320a inhibits cell proliferation,migration and invasion by targeting BMI-1 in nasopharyngeal carcinoma

In the present study, we investigated the roles and molecular mechanisms of miR-320a in human nasopharyngeal carcinoma (NPC). miR-320a expression was strongly reduced in NPC tissues and cell lines. Overexpression of miR-320a significantly suppressed NPC cell growth, migration, invasion and tumor growth in a xenograft mouse model. A luciferase reporter assay revealed that miR-320a could directly bind to the 3′ UTR of BMI-1. Overexpression of BMI-1 rescued miR-320a-mediated biological function. BMI-1 expression was found to be up-regulated and inversely correlated with miR-320a expression in NPC. Collectively, our data indicate that miR-320a plays a tumor suppressor role in the development and progression of NPC and may be a novel therapeutic target against NPC.     

MicroRNA-124 upregulation inhibits proliferation and invasion of osteosarcoma cells by targeting sphingosine kinase 1

Increasing evidence has confirmed that the dysregulation of microRNAs (miRNAs) contributes to the proliferation and invasion of human cancers. Previous studies have shown that the dysregulation of miR-124 is in numerous cancers. However, the roles of miR-124 in human osteosarcoma (OS) have not been well clarified. Therefore, this study was to investigate the biological functions and molecular mechanisms of miR-124 in OS cell lines, discussing whether it could be a therapeutic biomarker of OS in the future. In this study, our results demonstrated that miR-124 was down-regulated in OS cell lines and tissues. Furthermore, the low level of miR-124 was associated with increased expression of Sphingosine kinase 1 (SPHK1) in OS cells and tissues. Up-regulation of miR-124 significantly inhibited cell proliferation, invasion, and MMP-2 and -9 expressions of OS cells. Bioinformatics analysis predicted that the SPHK1 was a potential target of miR-124. Further study by luciferase reporter assay demonstrated that miR-124 could directly target SPHK1. Overexpression of SPHK1 in OS cells transfected with miR-124 mimic partially reversed the inhibitory of miR-124. In conclusion, miR-124 inhibited cell proliferation and invasion in OS cells by downregulation of SPHK1, and that downregulation of SPHK1 was essential for the miR-124-inhibited cell invasion and in OS cells.     

MicroRNA-144 inhibits hepatocellular carcinoma cell proliferation,invasion and migration by targeting ZFX

MicroRNA 144 (miR-144), a small non-coding RNA, is frequently dysregulated in human several tumour progression, but its role and the underlying mechanisms in hepatocellular carcinoma (HCC) is poorly investigated. In the present study, the expression of miR-144 was firstly analysed in datasets derived from GSE21362 and TCGA, and then detected in HCC tissues and cell lines by quantitative RT-PCR (qRT-PCR) analysis. MiR-144 was shown to be significantly down-regulated in HCC tissues and cell lines. Subsequently, overexpression of miR-144 was transfected into HCC cell lines so as to investigate its biological function, including MTT, colony formation, and transwell assays. Gain of function assay revealed miR-144 remarkably inhibited cell proliferation, migration and invasion. In addition, bioinformatical analysis and luciferase reporter assay identified ZFX as a novel target of miR-144 in HCC cells, as confirmed by qRT-PCR and Western blot. Furthermore, ZFX was found to be significantly up-regulated using Oncomine database analysis. Loss of function assay further indicated knockdown of ZFX had similar effects of miR-144-mediated HCC cell proliferation and invasion. Therefore, miR-144 has been demonstrated to act as a tumour suppressor in HCC cell growth and motility by directly targeting ZFX, which implicates its potential applications in the development of HCC treatment.     

Stimulation of cell invasion and migration by alcohol in breast cancer cells

Increasing epidemiological studies suggest that alcohol consumption confers a high risk for development of breast cancer. In this study, we found that biologically relevant concentrations of alcohol elicited a significant stimulation of cell adhesion, migration, and invasion in MCF-7 human breast cancer cells. Moreover, the promotion of invasion and migration potential by alcohol was associated with the significant decrease of E-cadherin, alpha, beta, and gamma three major catenin, and BRCA1 expression. In addition, an enhanced expression of BRCA1 significantly blocked alcohol-stimulated cell invasion. Thus, our present study suggests that alcohol as a breast cancer risk factor plays an important role not only in carcinogenesis, but also in promotion of cell invasion and migration.     

MicroRNA-185 suppresses proliferation, invasion, migration, and tumorigenicity of human prostate cancer cells through targeting androgen receptor

Previous studies have shown that androgen receptor (AR) is involved in the progression of prostate cancer (CaP) by several mechanisms. However, how AR is regulated has not been fully understood. In this study, miR-185 was found to be down-regulated in clinical CaP samples. Targets prediction revealed that AR had putative complementary sequences to miR-185, which was confirmed by the following dual luciferase reporter assay. Overexpression of miR-185 could reduce the expression of AR protein but not mRNA in LNCaP cells. The proliferation of LNCaP cells was inhibited by overexpression of miR-185. Cell cycle analysis revealed cell cycle arrest at G0/G1 phase. The invasive and migration abilities of cells could also be suppressed by miR-185. Furthermore, miR-185 inhibited tumorigenicity in a CaP xenografts model. CDC6, one target of AR and an important regulatory molecule for cell cycle, was found to be down-regulated by overexpression of miR-185. Our findings suggest that miR-185 could function as a tumor-suppressor gene in CaP by directly targeting AR, and act as a potential therapeutic target for CaP.     

MicroRNA-221 promotes colorectal cancer cell invasion and metastasis by targeting RECK

MicroRNAs (miRNAs) have recently emerged as regulators of metastasis. We provide insight into the behavior of miR-221 in colorectal cancer (CRC) metastasis by showing that miR-221 is significantly upregulated in metastatic CRC cell lines and tissues. miR-221 overexpression enhances, whereas miR-221 depletion reduces CRC cell migration and invasion in vitro and metastasis in vivo. We identify RECK as a direct target of miR-221, reveal its expression to be inversely correlated with miR-221 in CRC samples and show that its re-introduction reverses miR-221-induced CRC invasiveness. Collectively, miR-221 is an oncogenic miRNA which may regulate CRC migration and invasion through targeting RECK.     

miR-335 suppresses migration and invasion by targeting ROCK1 in osteosarcoma cells

Dynamic remodeling of the actin cytoskeleton is crucial for biological processes such as cell migration and cell spreading. S100A10 is a member of the S100 protein family and is involved in intracellular trafficking and cell migration. In this study, we examined the role of S100A10 in actin cytoskeletal organization and cell spreading. Depletion of S100A10 induced disruption of stress fiber formation and delay in cell spreading. Rac1 activation during spreading was suppressed by S100A10 knockdown, and exogenous expression of active Rac1 restored the ability of cells to spread in the absence of S100A10. Our results demonstrate the crucial role of S100A10 in actin dynamics promoting cell spreading via Rac1 activation.     

Metadherin mediates lipopolysaccharide-induced migration and invasion of breast cancer cells

Background

Breast cancer is the most prevalent cancer in women worldwide and metastatic breast cancer has very poor prognosis. Inflammation has been implicated in migration and metastasis of breast cancer, although the exact molecular mechanism remains elusive.

Principal Findings

We show that the pro-inflammatory endotoxin Lipopolysaccharide (LPS) upregulates the expression of Metadherin (MTDH), a recently identified oncogene, in a number of breast cancer lines. Stable knockdown of MTDH by shRNA in human breast MDA-MB-231 cells abolishes LPS-induced cell migration and invasion as determined by several in vitro assays. In addition, knockdown of MTDH diminishes Nuclear Factor-kappa B (NF-κB) activation by LPS and inhibited LPS-induced IL-8 and MMP-9 production.

Conclusions

These results strongly suggest that MTDH is a pivotal molecule in inflammation-mediated tumor metastasis. Since NF-κB, IL-8 and MMP-9 play roles in LPS-induced invasion or metastasis, the mechanism of MTDH-promoted invasion and metastasis may be through the activation of NF-κB, IL-8 and MMP-9, also suggesting a role of MTDH in regulating both inflammatory responses and inflammation-associated tumor invasion. These findings indicate that MTDH is involved in inflammation-induced tumor progression, and support that MTDH targeting therapy may hold promising prospects in treating breast cancer.