MiR-18a regulates the proliferation,migration and invasion of human glioblastoma cell by targeting neogenin

MiR-17-92 cluster has recently been reported as an oncogene in some tumors. However, the association of miR-18a, an important member of this cluster, with glioblastoma remains unknown. Therefore, this study aims to investigate the expression of miR-18a in glioblastoma and its role in biological behavior of U87 and U251 human glioblastoma cell lines. Quantitative RT-PCR results showed that miR-18a was highly expressed in glioblastoma tissues and U87 and U251 cell lines compared with that in human brain tissues and primary normal human astrocytes, and the expression levels were increased along with the rising pathological grades of glioblastoma. Neogenin was identified as the target gene of miR-18a by dual-luciferase reporter assays. RT-PCR and western blot results showed that its expression levels were decreased along with the rising pathological grades of glioblastoma. Inhibition of miR-18a expression was established by transfecting exogenous miR-18a inhibitor into U87 and U251 cells, and its effects on the biological behavior of glioblastoma cells were studied using CCK-8 assay, transwell assay and flow cytometry. Inhibition of miR-18a expression in U87 and U251 cells significantly up-regulated neogenin, and dramatically suppressed the abilities of cell proliferation, migration and invasion, induced cell cycle arrest and promoted cellular apoptosis. Collectively, these results suggest that miR-18a may regulate biological behavior of human glioblastoma cells by targeting neogenin, and miR-18a can serve as a potential target in the treatment of glioblastoma.     

MiR-206 regulates neural cells proliferation and apoptosis via Otx2

MiR-206 was involved in a series of cellular activities, such as the growth and development of skeletal muscle and the tumorigenesis. MiR-206 was characterized previously as a differentially expressed gene in sodium arsenite (SA)-induced neural tube defects (NTDs) in chick embryos via miRNA microarray analysis. However, the role of miR-206 in the pathological process of nerve cells remained elusive. In this study we found differential expression of miR-206 in SA-treated chick embryos by Northern blot analysis. Ectopic expression of miR-206 inhibited cell proliferation, and promoted cell apoptosis in U343 and SK-N-SH cell by using MTT, Edu Apollo assay and Flow cytometry analysis. Further investigation revealed that miR-206 can interact with 3'-untranslated region (UTR) of Otx2. MiR-206 mimics down-regulated the endogeneous Otx2 expression, whereas the miR-206 inhibitor obviously up-regulated the expression of Otx2. These findings indicate that overexpression of miR-206 promotes cell apoptosis and low expression of miR-206 inhibits cell apoptosis. Otx2 may play an important role in the process of miR-206-mediated cell apoptosis.     

GOLPH3 regulates the migration and invasion of glioma cells though RhoA

Golgi phosphoprotein 3 (GOLPH3) has been reported to be involved in the development of several human cancers. However, the biological significance of GOLPH3 in glioma progression remains largely unknown. In this study, we report, for the first time, that downregulation of GOLPH3 led to clear reductions in glioma cell migration and invasion. In addition, downregulation of GOLPH3 inhibited the expression of the small GTPase RhoA as well as cytoskeletal reorganization, which are both required for glioma cell migration. Furthermore, we found that the observed reductions in glioma cell migration and RhoA level could be rescued by RhoA overexpression. Taken together, these results show that GOLPH3 contributes to the motility of glioma cells by regulating the expression of RhoA.     

COX-2 regulates the proliferation of glioma stem like cells

Cancer stem-like cells (CSCs) possessing features of neural precursor cells (NPC) influence initiation, recurrence and chemoresistance of glioblastoma multiforme (GBM). As inflammation is crucial for glioblastoma progression we investigated the effect of chronic IL-1β treatment on CSCs derived from glioblastoma cell line U87MG. Exposure to IL-1β for 10 days increased (i) accumulation of 8-OHdG - a key biomarker of oxidative DNA damage; (ii) DNA damage response (DDR) indicators γH2AX, ATM and DNA-PK; (iii) nuclear and cytoplasmic p53 and COX-2 levels and (iv) interaction between COX-2 and p53. Despite upregulating p53 expression IL-1β had no effect on cell cycle progression, apoptosis or self renewal capacity of CSCs. COX-2 inhibitor Celecoxib reduced self renewal capacity and increased apoptosis of both control and IL-1β treated CSCs. Therefore the ability of COX-2 to regulate proliferation of CSCs irrespective of exposure to IL-1β, warrants further investigation of COX-2 as a potential anti-glioma target.     

MiR-216a-3p regulates the proliferation,apoptosis, migration,and invasion of lung cancer cells via targeting COPB2

ABSTRACT

Effect of miR-216a-3p on lung cancer hasn’t been investigated. Here, we explored its effects on lung cancer. MiR-216a-3p expression in lung cancer tissues and cells was detected by RT-qPCR. The target gene of miR-216a-3p was predicted by bioinformatics and confirmed by luciferase-reporter assay. After transfection, cell viability, migration, invasion, proliferation, and apoptosis were detected by MTT, scratch, transwell, colony formation, and flow cytometry. The expressions of COPB2 and apoptosis-related factors were detected by RT-qPCR or western blot. MiR-216a-3p was low-expressed and COPB2 was high-expressed in lung cancer tissues and cells. MiR-216a-3p targeted COPB2 and regulated its expression. MiR-216a-3p inhibited lung cancer cell viability, migration, invasion, and proliferation, while promoted apoptosis. Effect of miR-216a-3p on lung cancer was reversed by COPB2. MiR-216a-3p regulated proliferation, apoptosis, migration, and invasion of lung cancer cells via targeting COPB2.     

MiR-135b improves proliferation and regulates chemotherapy resistance in ovarian cancer

Journal of Molecular Histology - MicroRNAs act as regulators in ovarian tumorigenesis and progression by involving different molecular pathways. Here, we examined the role of miR-135b on growth,...     

c‐Cbl regulates glioma invasion through matrix metalloproteinase 2

c‐Cbl, a multifunctional adaptor and an E3 ubiquitin ligase, plays a role in such cytoskeleton‐mediated events as cell adhesion and migration. Invasiveness of human glioma is dependent on cell adhesion, migration, and degradation of extracellular matrix (ECM). However, the function of c‐Cbl in glioma invasion has never been investigated. We report here, for the first time, that c‐Cbl plays a positive role in the invasion of ECM by SNB19 glioma cells. RNAi‐mediated depletion of c‐Cbl decreases SNB19 cell invasion and expression of matrix metalloproteinase 2 (MMP2). Consistent with these findings, SNB19 cells expressing wild‐type, but not mutant c‐Cbl show increased invasion and MMP2 expression. We demonstrate that the observed role of c‐Cbl in invasion of SNB19 cells is not mediated by the previously shown effects of c‐Cbl on cell adhesion and migration or on EGFR signaling. Together, our results suggest that c‐Cbl promotes glioma invasion through up‐regulation of MMP2. J. Cell. Biochem. 111: 1169–1178, 2010. © 2010 Wiley‐Liss, Inc.     

MiR-483-5p suppresses the proliferation of glioma cells via directly targeting ERK1

MicroRNAs (miRNAs) exhibit tumor-specific expression signatures and play crucial roles in tumorigenesis by targeting oncogenes. Here, through analyzing the miRNA-array profiles of human glioblastoma tissues and the adjacent normal brain tissues, we found miR-483-5p was significantly down-regulated in gliomas, which was confirmed in both human glioma specimens and cell lines. The overexpression of miR-483-5p suppressed glioma cell proliferation and induced a G0/G1 arrest. In contrast, miR-483-5p inhibition promoted cell proliferation. Furthermore, by a dual-luciferase reporter assay and expression analysis, we identified extracellular signal-regulated kinase 1 (ERK1) as a direct target of miR-483-5p. ERK1 knockdown can block cell proliferation induced by miR-483-5p inhibition. Thus, our findings provide the first evidence that miR-483-5p can serve as a tumor suppressor in gliomas.     

Notch1 regulates tongue cancer cells proliferation,apoptosis and invasion

Objectives: Notch1 regulates tumor biology in a complex, context-dependent manner. The roles of Notch1 in tongue cancer are still controversial. The aim of this study is to investigate the roles of Notch1 in tongue cancer.

Materials and Methods: The expression of Notch1 was tested between tongue cancer and normal samples by using immunohistochemistry. Tongue cancer cells were transfected with siRNA or plasmid, respectively. Cell proliferation, apoptosis, migration and invasion ability were tested in appropriate ways. The subcutaneous tumor model was established to observe the tumor growth.

Results: Notch1 was upregulated in tongue carcinoma tissues and the expression of Notch1 was related with tumor stage and differentiation. Overexpression of Notch1 could increase tongue cancer cells proliferation, invasion and migration. But inhibited the expression of Notch1 could decrease cells proliferation, invasion and migration and promote cell apoptosis in vitro and in vivo.

Conclusion: Our results prove that the oncogenic role of Notch1 in tongue cancer and provide the direction of targeted therapy of tongue cancer.     

MiR-126-3p inhibits ovarian cancer proliferation and invasion via targeting PLXNB2

Ovarian cancer is one of the leading malignancies in women and the 5-year survival rate of ovarian cancer still remains poor. In the present study, we aimed to investigate the interaction between the miR-126-3p and PLXNB2 in the progression of ovarian cancer. The qRT-PCR data revealed a reduction of miR-126-3p level in ovarian cancer tissues comparing to the adjacent normal tissues. Over-expression of miR-126-3p in ovarian cancer cells suppressed cell proliferation and invasion and the phosphorylation of AKT and ERK1/2. The cell cycle assay results showed that the over-expression of miR-126-3p induced cells in G1-phase and reduced cells in S-phase. We further performed bioinformatics analysis and luciferase assay to investigate the relationship between miR-126-3p and PLXNB2 in ovarian cancer cells. The results of TargetScan suggested that PLXNB2 is a direct target of miR-126-3p in ovarian cancer cells, and luciferase assay confirmed bioinformatics prediction. Knocking down of PLXNB2 with PLXNB2 siRNA results in repressed ovarian cancer cell proliferation and invasion, and decreased phosphorylation of AKT and ERK1/2, which is similar to the effect of over-expression of miR-126-3p in OC cells. The synergistic effect of combination of miR-126-3p over-expression and PLXNB2 down-regulation on the cell growth viability, cell colony, and cell invasion was also identified. All these findings indicated that miR-126-3p is involved in the progression of ovarian cancer via direct regulating PLXNB2.     

TRAF6 regulates proliferation, apoptosis, and invasion of osteosarcoma cell

Hepatocellular carcinoma is becoming one of the most prominent types of cancer in the world. Recently, from Styrax japonica Siebold et al. Zuccarini (SJSZ), we isolated a glycoprotein which consists of carbohydrate moiety (52.64%) and protein moiety (42.35%). We evaluated whether SJSZ glycoprotein prevents hepatocarcinogenesis induced by N-nitrosodiethylamine (DEN). The purpose of this study was to evaluate the effect of SJSZ glycoprotein in DEN-induced hepatocarcinogenesis in ICR mice. To know chemopreventive effect of SJSZ glycoprotein on hepatocarcinogenesis, ICR mice were intraperitoneally injected with N-nitrosodiethylamine (DEN, 10 mg/kg) for 7 weeks. After sacrifice, we evaluated indicators of liver tissue damage [the activities of lactate dehydrogenase (LDH) and alanine aminotransferase (ALT), and thiobarbituric acid reactive substances (TBARS)], antioxidative enzymes [activities of superoxide dismutase (SOD), catalase (CAT) and glutathione peroxidase (GPx)], and initiating hepatocarcinogenic indicator [heat shock protein (HSP) 27 and 70] and hepatocarcinogenic signals [protein kinase C (PKC), extracellular signal-regulating kinase (ERK) 1/2, nuclear factor (NF)-κB (p50 and p65) and tumor necrosis factor-α (TNF-α)] using biochemical methods, immunoblot analysis, and RT-PCR. The results obtained from this study revealed that SJSZ glycoprotein (10 mg/kg, BW) decreased the levels of LDH, ALT, and TBARS, whereas the activities of SOD, GPx, and CAT increased in the DEN-induced ICR mice. With respect to the hepatocarcinogenic indicator and hepatocarcinogenic signals, HSP27, HSP70, PKC, ERK1/2, NF-κB (p50 and p65), and TNF-α, activity decreased. Hence, SJSZ glycoprotein might prevent expression of HSP27 and HSP70 by DEN.     

SASH1 regulates proliferation, apoptosis, and invasion of osteosarcoma cell

SASH1, a member of the SLY-family of signal adapter proteins, is a candidate tumor suppressor in breast and colon cancer. The SASH1 protein possesses both the SH3 and SAM domains, indicating that it may play an important role in intracellular signal transduction. Reduced expression of SASH1 is closely related to tumor growth, invasion, metastasis, and poor prognosis. However, the biological role of SASH1 remains unknown in osteosarcoma. To unravel the function of SASH1, we explored the expression of SASH1 in osteosarcoma tissues and its correlation to the clinical pathology of osteosarcoma and analyzed the relationship between SASH1 expression and cell cycle, apoptosis and invasion of osteosarcoma MG-63 cells, using the flow cytometry analysis and transwell invasion chamber experiments. Furthermore, the effect of SASH1 on the expression of cyclin D1, caspase-3, matrix metalloproteinase (MMP)-9 were observed by western blot. Our results showed that the expression rate of SASH1 mRNA in osteosarcoma tissues was significantly lower than that in normal bone tissue (p = 0.000), that the expression rate of SASH1 mRNA in the carcinoma tissues from patients with lung metastasis was significantly lower than that from patients without lung metastasis (p = 0.041), and that the expression rate of SASH1 mRNA also decreased with increasing Enneking stage (p = 0.032). However, the mRNA expression of SASH1 in osteosarcoma was independent of the patient’s gender, age, and tumor size (p = 0.983, 0.343, 0.517, respectively). The SASH1 protein displayed a down-regulation in osteosarcoma tissues compared to normal bone tissue (p = 0.000), displayed a down-regulation in osteosarcoma tissues from patients with lung metastasis compared to from patients without lung metastasis (p = 0.000), and displayed a gradual decrease with increasing Enneking stage (p = 0.000). In addition, the MG-63 cells from pcDNA3.1-SASH1 group exhibited significantly reduced cell viability, proliferation, and invasive ability compared to the empty vector group and blank control group (p = 0.023, 0.001, respectively), and there was no difference between the empty vector group and blank control group. The pcDNA3.1-SASH1 group displayed significantly more apoptotic cells than the empty vector group and blank control group (p = 0.004). The expression of cyclin D1, MMP-9 displayed a down-regulation in MG-63 cells from pcDNA3.1-SASH1 group compared to the empty vector group and blank control group (p = 0.000, 0.001, respectively) and the expression levels of caspase-3 displayed an up-regulation in MG-63 cells from pcDNA3.1-SASH1 group compared to the empty vector group and blank control group (p = 0.000). Taken together, these data indicated that the overexpression of SASH1 might be associated with the inhibition of growth, proliferation, and invasion of MG-63 cells and the promotion of apoptosis of MG-63 cells.     

MiR-181c modulates the proliferation,migration, and invasion of neuroblastoma cells by targeting Smad7

MicroRNAs （miRNAs） function as key regulators of gene expression in various cancers. In this study, the aim is to explore the roles and regulation mechanism of miR-181c in neuroblastoma （NB） cells. We found that miR-181c was downregulated in metastatic NB tissues, compared with primary NB tissues. Then functional studies indicated that miR-181 c overexpression inhibited NB cell proliferation, migration, and invasion, while miR-181c inhibition increased cell proliferation, migration, and invasion. EGFP reporter assay, real-time polymerase chain reaction and western blot analysis validated that Smad7 was a direct target of miR- 181c. MiR-181c reduced Smad7 expression at both mRNA and protein levels. Finally, functional assays showed that the effect of Smad7 knockdown on cells was similar to that of miR-181c overexpression. Importantly, Smad7 overexpression could restore the antitumor effects that were induced by miR-181 c. In conclusion, our results demonstrated that miR- 181c inhibits NB cell growth and metastasis-related traits through the suppression of SmadT, functioning as a tumor suppressor. Moreover, our results suggested that miR-181c may serve as an important therapeutic target for NB patients.