LRRC4 Inhibits Glioma Cell Growth and Invasion Through a miR-185- Dependent Pathway

Cancer Research Institute, Central South University, Changsha 410078 Hunan, P.R. China. .
Current cancer drug targets (Impact Factor: 3.52). 07/2012; 12(8):1032-42. DOI: 10.2174/156800912803251180
Source: PubMed


Leucine-rich repeat (LRR) genes encode transmembrane proteins that are essential for normal brain development and are often dysregulated in central nervous system tumors. Leucine-rich repeat C4 (LRRC4) is a member of the LRR protein superfamily and specifically expressed in brain tissue. Importantly it acts as a tumor suppressor in the pathogenesis of malignant gliomas. However, the molecular mechanisms by which LRRC4 regulates glioma tumorigenesis are largely unknown. In this report, we found that miR-185 is markedly upregulated by LRRC4. We also found that miR-185 was downregulated in glioma, and overexpression of miR-185 inhibited glioma cell invasion. Low expressions of LRRC4 and miR-185 were associated with a poor outcome in glioma patients. Further investigation revealed that LRRC4 mediated its tumor suppressor function by regulating miR-185 targets CDC42 and RhoA. LRRC4 overexpression inhibited glioma cell invasion through miR-185-mediated CDC42 and RhoA direct regulation and VEGFA indirect regulation. Together, our findings suggest that the altered expression of the tumor suppressor LRRC4 may be an important event that leads to the dysregulation of miR-185 in human gliomas. LRRC4 and miR-185 may also be good prognostic markers and therapeutic targets in glioma.

Download full-text


Available from: Minghua Wu, Jul 04, 2014
  • Source
    • "The cell invasion assay was conducted as described previously [18]. Briefly, cells were seeded onto the basement membrane matrix present in the insert of a 24-well culture plate (EC matrix, Chemicon, Temecula, CA). "
    [Show abstract] [Hide abstract]
    ABSTRACT: miR-200b has been reported to be a tumor suppressor and a promising therapeutic target in cancer. miR-200b has been associated with epithelial-mesenchymal transition and chemo-resistance in cancer. The aim of this study is to investigate the expression of miR-200b, its prognostic roles and its potential targets in breast cancer. qRT-PCR was used to detect miR-200b expression in breast cancer tissues and cell lines. In situ hybridization of miR-200b on tissue microarray including 134 breast cancer samples was used to evaluate its prognostic role. Novel targets of miR-200b in breast cancer were predicted and confirmed by luciferase reporter assay and western bloting. Immunohistochemical staining was used for protein detection. The biological effects of miR-200b in breast cancer cells were further confirmed by ectopic expression of its mimics followed by MTT assay and invasion test. miR-200b was downregulated in breast cancer tissues and cell lines and its low-expression correlated with poor outcome in breast cancer patients. Members of RAB family, RAB21, RAB23, RAB18 and RAB3B were predicted to be the targets of miR-200b. The luciferase reporter assay was performed to certificate this prediction. The expressions of RAB21, RAB23, RAB18 and RAB3B were suppressed by transfection of miR-200b in breast cancer cells. Over-expression of miR-200b or knock-down of RAB21, RAB23, RAB18 and RAB3B inhibited breast cancer cell proliferation and invasion in vitro. Our study provides evidence that miR-200b is a prognostic factor in breast cancer targeting multiple members of RAB family. MiR-200b could be a potential therapeutic target in breast cancer.
    Journal of Translational Medicine 01/2014; 12(1):17. DOI:10.1186/1479-5876-12-17 · 3.93 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: We previously reported that miR-185 is associated with hepatocellular carcinoma (HCC) venous metastasis analysed by miRNA-array profile. The aim of this study is to further investigate the clinicopathological significance and prognostic value of miR-185 in early stage HCC. We classified 95 patients with early stage HCC into treated recurrence group (TR) and none treated recurrence group (NTR), and detected the miR-185 expression levels in TR and NTR groups. We found that low miR-185 expression correlated with more tumor recurrence (37/46), while high miR-185 level led to lower recurrence rate (17/49) (P<0.05). There was no direct relationship between miR-185 and clinicopathological features, including age, gender, ALT, AFP, liver cirrhosis, tumor size, tumor encapsulation, tumor differentiation (P>0.05). Kaplan-Meier analysis showed that low miR-185 group had a remarkable lower survival rate and shorter time to recurrence than high miR-185 group (P<0.05). Univariate and multivariate analysis, using Cox's proportional hazards model, also indicated that low miR-185 expression was a sensitive prognostic factor for survival and recurrence in early stage HCC (P<0.05). We upregulated or downregulated miR-185 expression by transfected miR-185 mimics or inhibitor into HCC cell lines, and observed the influence of miR-185 on HCC cells in vitro. Our results manifested that miR-185 could suppress the tumor cell growth and invasive ability (P<0.05). Therefore, miR-185 might be an effective and sensitive biomarker of HCC in early stage, and the upregulation of miR-185 might be considered to be a potentially important molecular treatment strategy for patients with HCC.
    Biomedicine & pharmacotherapy = Biomedecine & pharmacotherapie 04/2013; 67(5). DOI:10.1016/j.biopha.2013.03.022 · 2.02 Impact Factor
  • [Show abstract] [Hide abstract]
    ABSTRACT: To explore the role and mechanism of microRNA185 (miR-185) on proliferation, migration and invasion of esophageal squamous cell carcinoma (ESCC). Samples were obtained from 23 ESCC patients undergoing surgery whose were confirmed by pathological diagnosis of esophageal carcinoma from 2002 to 2012,at Department of Thoracic Surgery,Cancer Institute and Cancer Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College. Real-time PCR was used to measure the expression of miR-185. The xCELLigence RTCA MP system and Transwell assay were performed to detect the effect of miR-185 on proliferation, migration and invasion of ESCC respectively. After transfectiing of miR-185 mimic into KYSE150, the expression of Six1's downstream gene cyclin A1 was evaluated by real-time PCR. After transfection of miR-185 inhibitor into KYSE30, the expression of E-cadherin, a downstream protein of Six1, was observed under confocal microscope. The expression level of miR-185 was down-regulated in ESCC compared with adjacent normal tissue (0.006 vs 0.039,P = 0.016). After transfection of miR-185 mimic, miR-185 significantly inhibited proliferation, migration and invasion of ESCC.Transwell assay showed, in comparison with the control group, the number of KYSE150 metastatic and invasive cells was respectively decreased(146 ± 15 vs 64 ± 11, 110 ± 12 vs 67 ± 5, both P < 0.05). And the expression level of cyclin A1 decreased. After transfection of miR-185 inhibitor,the expression level of E-cadherin decreased. miR-185 may inhibit proliferation, migration and invasion of ESCC through its target gene Six1.
    Zhonghua yi xue za zhi 05/2013; 93(18):1426-31. DOI:10.3760/cma.j.issn.0376-2491.2013.18.015
Show more