MTDH

Gene Summary

Gene:MTDH; metadherin
Aliases: 3D3, AEG1, AEG-1, LYRIC, LYRIC/3D3
Location:8q22.1
Summary:-
Databases:VEGA, OMIM, HGNC, Ensembl, GeneCard, Gene
Protein:protein LYRIC
Source:NCBIAccessed: 15 March, 2017

Ontology:

What does this gene/protein do?
Show (25)

Cancer Overview

Research Indicators

Publications Per Year (1992-2017)
Graph generated 15 March 2017 using data from PubMed using criteria.

Literature Analysis

Mouse over the terms for more detail; many indicate links which you can click for dedicated pages about the topic.

Tag cloud generated 15 March, 2017 using data from PubMed, MeSH and CancerIndex

Latest Publications: MTDH (cancer-related)

Park SY, Choi M, Park D, et al.
AEG-1 promotes mesenchymal transition through the activation of Rho GTPases in human glioblastoma cells.
Oncol Rep. 2016; 36(5):2641-2646 [PubMed] Related Publications
Despite growing evidence indicating that astrocyte elevated gene-1 (AEG-1) plays pivotal roles in tumor progression in various types of human cancers including brain tumors; to date, its role in the regulation of mesenchymal transition is not clear in glioblastoma. In the present study, we investigated the contribution of AEG-1 to stress fiber formation and then the acquisition of mesenchymal characteristics of glioblastoma cells. Gain- and loss-of-function studies in normal immortalized primary human fetal astrocytes (IM-PHFAs) and glioblastoma cells revealed that overexpression of AEG-1 increased expression of mesenchymal markers including N-cadherin and two mesenchymal transition‑inducing transcription factors ZEB1 and Slug but decreased epithelial markers E-cadherin and ZO-1. In addition, knockdown of AEG-1 suppressed invasive ability and migration of glioblastoma cells. Overexpression of AEG-1 also induced stress fiber formation and activated the Rho GTPase signaling pathways in glioblastoma cells. Consistently, treatment with an RhoA inhibitor decreased AEG-1-mediated stress fiber formation in glioblastoma cells. Collectively, our findings suggest that AEG-1 promotes mesenchymal transition in glioblastoma through the regulation of the Rho signaling pathway, resulting in tumor invasion, a primary characteristic of malignant brain tumors.

Zhang X, Cai D, Meng L, Wang B
MicroRNA-124 inhibits proliferation, invasion, migration and epithelial-mesenchymal transition of cervical carcinoma cells by targeting astrocyte-elevated gene-1.
Oncol Rep. 2016; 36(4):2321-8 [PubMed] Related Publications
MicroRNA-124 (miR-124) was reported to be attenuated in human cervical cancer (CC) specimens. However, its role in CC remains elusive. In the present study, quantitative real-time PCR (qRT-PCR) analysis demonstrated that miR-124 expression is significantly downregulated in human CC tissues and several CC cell lines. Transfection of miR-124 mimics in CC cell lines HeLa and SiHa markedly inhibits cell proliferative, migratory and invasive capacities, as well as the epithelial-mesenchymal transition (EMT) process in vitro. Further studies have identified astrocyte-elevated gene-1 (AEG-1) as a direct target gene of miR-124. miR-124 downregulated AEG-1 expression through interaction with its 3'-untranslated regions (3'-UTRs), and miR-124 expression was inversely correlated with AEG-1 levels in CC specimens. Moreover, exogenous overexpression of AEG-1 significantly rescued the miR-124-induced inhibition of cell proliferation, migration and invasion, as well as the EMT process in HeLa cells. In conclusion, these findings suggested that miR-124 was able to suppress cell proliferation, invasion and migration, as well as the EMT process in cervical carcinomas through directly targeting AEG-1. miR-124 and AEG-1 may be potential therapeutic targets for the treatment of cervical carcinoma.

Abozeid SM, Hathout RM, Abou-Aisha K
Silencing of the metastasis-linked gene, AEG-1, using siRNA-loaded cholamine surface-modified gelatin nanoparticles in the breast carcinoma cell line MCF-7.
Colloids Surf B Biointerfaces. 2016; 145:607-16 [PubMed] Related Publications
Cholamine surface-modified gelatin nanoparticles prepared by the double desolvation method using acetone as a dehydrating agent were selected and potentially evaluated as non viral vectors of siRNA targeting a metastatic gene AEG-1 in MCF-7 breast carcinoma cells. The ability of modified gelatin nanoparticle to complex and deliver siRNA for gene silencing was investigated. Hence, Particle size, surface charge (zeta potential) and morphology of siRNA/Gelatin nanoparticles (siGNPs) were characterized via dynamic light scattering (DLS), scanning electron microscopy (SEM) and transmission electron microscope (TEM). Moreover, the nanoparticles cytotoxicity, loading efficiency and interaction with MCF-7 human breast carcinoma cells were evaluated. Cationized GNPs of mean size range of 174nm and PDI of 0.101 were produced. The loading efficiency of siGNPs at a Nitrogen/Phosphate (N/P) ratio (w/w) of 200:1 was approximately 96%. Cellular uptake was evaluated after FITC conjugation where the particles produced high transfection efficiency. Finally, ELISA analysis of AEG-1/MTDH expression demonstrated the gene silencing effect of siGNPs, as more than 75% MTDH protein were inhibited. Our data indicate that cholamine modified GNPs pose a promising non-viral siRNA carrier for altering gene expression in MCF-7 breast cancer cells with many advantages such as relatively high gene transfection efficiency and efficient silencing ability.

Zhu W, Lee SJ, Castro NJ, et al.
Synergistic Effect of Cold Atmospheric Plasma and Drug Loaded Core-shell Nanoparticles on Inhibiting Breast Cancer Cell Growth.
Sci Rep. 2016; 6:21974 [PubMed] Free Access to Full Article Related Publications
Nano-based drug delivery devices allowing for effective and sustained targeted delivery of therapeutic agents to solid tumors have revolutionized cancer treatment. As an emerging biomedical technique, cold atmospheric plasma (CAP), an ionized non-thermal gas mixture composed of various reactive oxygen species, reactive nitrogen species, and UV photons, shows great potential for cancer treatment. Here we seek to develop a new dual cancer therapeutic method by integrating promising CAP and novel drug loaded core-shell nanoparticles and evaluate its underlying mechanism for targeted breast cancer treatment. For this purpose, core-shell nanoparticles were synthesized via co-axial electrospraying. Biocompatible poly (lactic-co-glycolic acid) was selected as the polymer shell to encapsulate anti-cancer therapeutics. Results demonstrated uniform size distribution and high drug encapsulation efficacy of the electrosprayed nanoparticles. Cell studies demonstrated the effectiveness of drug loaded nanoparticles and CAP for synergistic inhibition of breast cancer cell growth when compared to each treatment separately. Importantly, we found CAP induced down-regulation of metastasis related gene expression (VEGF, MTDH, MMP9, and MMP2) as well as facilitated drug loaded nanoparticle uptake which may aid in minimizing drug resistance-a major problem in chemotherapy. Thus, the integration of CAP and drug encapsulated nanoparticles provides a promising tool for the development of a new cancer treatment strategy.

Chang Y, Li B, Xu X, et al.
Lentivirus-Mediated Knockdown of Astrocyte Elevated Gene-1 Inhibits Growth and Induces Apoptosis through MAPK Pathways in Human Retinoblastoma Cells.
PLoS One. 2016; 11(2):e0148763 [PubMed] Free Access to Full Article Related Publications
PURPOSE: To explore expression and function of astrocyte elevated gene-1 (AEG-1) in human retinoblastoma (RB).
METHODS: The expression of AEG-1 in histological sections of human RBs and in RB cell lines was examined using immunohistochemical staining and RT-PCR and Western blotting respectively. We knocked down AEG-1 gene levels by AEG-1-siRNA lentivirus transfection of human RB cell lines SO-RB50 and Y79, and using an MTT assay, we assessed the role of AEG-1 on RB cell proliferation. The biological significance of lentivirus transfection induced AEG-1 down-regulation was examined by assessing the apoptosis rate in the transfected RB cells by Annexin V-APC staining and flow cytometry. We additionally measured the expression of Bcl-2, Bax, cleaved-caspase-3 and caspase-3, and the phosphorylation and non-phosphorylation alternation of MAPKs.
RESULTS: AEG-1 expression was detected to be strongly positive in the histological slides of 35 out of 54 (65%) patients with RB. AEG-1 expression increased significantly (P<0.05) with tumor stage. In the RB cell lines SO-RB50, Y79 and WERI-RB1 as compared with retinal pigment epithelium cells, expression of AEG-1 mRNA and AEG-1 protein was significantly higher. In AEG-1-siRNA lentivirus transfected cell cultures as compared with negative control lentivirus transfected cell cultures, levels of AEG-1 mRNA and of AEG-1 protein (P<0.05) and cell growth rates (P<0.01) were significantly lower, and apoptosis rate (P<0.001), Bax/Bcl-2 ratio and cleaved-caspase-3 protein level were significantly increased. The P-ERK/ERK ratio was significantly decreased in the AEG-1-siRNA lentivirus transfected cell lines.
CONCLUSIONS: Expression of AEG-1 was associated with RB, in histological slides of patients and in cell culture experiments. Lentivirus transfection induced knockdown of AEG-1 had a tumor suppressive effect, potentially by tumor cell apoptosis induction through inhibition of ERK.

He R, Yang L, Lin X, et al.
MiR-30a-5p suppresses cell growth and enhances apoptosis of hepatocellular carcinoma cells via targeting AEG-1.
Int J Clin Exp Pathol. 2015; 8(12):15632-41 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: MiR-30a-5p has been reported to play vital roles in the carcinogenesis and progression of various malignancies via different molecular mechanisms. However, the role and target genes of miR-30a-5p in hepatocellular carcinoma (HCC) remain still unclear. In silico analysis finds that there are complementary sequences between the 3'-untrasnlated region of astrocyte elevated gene 1 (AEG-1) and miR-30a-5p. Herein, we investigated the biological function of miR-30a-5p, as well as the potential molecular mechanism via targeting AEG-1 in HCC cells.
MATERIALS AND METHODS: MiR-30a-5p inhibitor, miR-30a-5p mimic, AEG-1 siRNAs, as well as their negative controls were transfected into HCC cell lines HepG2, SMMC-7221, HepB3 and SNU449. Then, the in vitro influence and mechanism of miR-30a-5p on cell viability, proliferation, caspase-3/7 activity and apoptosis were studied, as assessed by different methods, including spectrophotometry, fluorimetry, fluorescence microscopy of Hoechst 33342/propidium iodide double chromatin staining, western blot and dual luciferase reporter assay, respectively.
RESULTS: MiR-30a-5p mimic markedly inhibited cell growth, also induced caspase-3/7 activity and apoptosis in all four HCC cell lines tested. The strongest effect was observed in HepG2 and SMMC-7721 cells. However, this effect was slightly weaker than that of AEG-1 siRNAs. Transfection of miR-30a-5p mimic led to a markedly reduced AEG-1 protein level and further dual luciferase reporter assay confirmed that AEG-1 was one of the target genes of miR-30a-5p in HCC cells.
CONCLUSIONS: MiR-30a-5p may play an essential role in the cell growth and apoptosis of HCC cells, partially via targeting AEG-1.

Meng F, Zhang L, Shao Y, et al.
MicroRNA-377 inhibits non-small-cell lung cancer through targeting AEG-1.
Int J Clin Exp Pathol. 2015; 8(11):13853-63 [PubMed] Free Access to Full Article Related Publications
Non-small-cell lung cancer (NSCLC) is the leading cause of cancer-related deaths. MicroRNAs (miRNAs) have been reported to be involved in tumorigenesis. However, the underlying mechanisms of microRNA-377 (miR-377) in NSCLC remain unknown. Hence, in the present study, we aimed to explore the role of miR-377 in the development of NSCLC, with identifying its target genes. The results showed that miR-377 expression was significantly decreased in NSCLC tissues as well as in NSCLC cell lines. Moreover, high expression of miR-377 could markedly inhibit the viability, proliferation, migration and invasion of NSCLC cells. The bioinformatics analysis results showed that astrocyte elevated gene-1 (AEG-1), an oncogene as previously reported, was a potential target gene of miR-377, which was further validated by dual-luciferase reporter assay. Besides, the expression of AEG-1 in protein level was decreased by miR-377 overexpression, but not in mRNA level. In addition, AEG-1 overexpression could reverse the inhibitory effects on NSCLC cells caused by miR-377 transfection. In conclusion, our results suggested that miR-377 played an important role in the development of NSCLC by regulating AEG-1 and may be a potential therapeutic target for NSCLC.

Luo Y, Zhang X, Tan Z, et al.
Astrocyte Elevated Gene-1 as a Novel Clinicopathological and Prognostic Biomarker for Gastrointestinal Cancers: A Meta-Analysis with 2999 Patients.
PLoS One. 2015; 10(12):e0145659 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: There have been numerous articles as to whether the staining index (SI) of astrocyte elevated gene-1 (AEG-1) adversely affects clinical progression and prognosis of gastrointestinal cancers. Nevertheless, controversy still exists in terms of correlations between AEG-1 SI and clinicopathological parameters including survival data. Consequently, we conducted a comprehensive meta-analysis to confirm the role of AEG-1 in clinical outcomes of gastrointestinal carcinoma patients.
METHODS: We performed a comprehensive search in PubMed, ISI Web of Science, Cochrane Central Register of Controlled Trials, EMBASE, Science Direct, Wiley Online Library, China National Knowledge Infrastructure (CNKI), WanFang and Chinese VIP databases. STATA 12.0 (STATA Corp., College, TX) was used to analyze the data extracted from suitable studies and Newcastle-Ottawa Scale was applied to assess the quality of included articles.
RESULTS: The current meta-analysis included 2999 patients and our results suggested that strong associations emerged between AEG-1 SI and histological differentiation (OR = 2.129, 95%CI: 1.377-3.290, P = 0.001), tumor (T) classification (OR = 2.272, 95%CI: 1.147-4.502, P = 0.019), lymph node (N) classification (OR = 2.696, 95%CI: 2.178-3.337, P<0.001) and metastasis (M) classification (OR = 3.731, 95%CI: 2.167-6.426, P<0.001). Furthermore, high AEG-1 SI was significantly associated with poor overall survival (OS) (HR = 2.369, 95%CI: 2.005-2.800, P<0.001) and deteriorated disease-free survival (DFS) (HR = 1.538, 95%CI: 1.171-2.020, P = 0.002). For disease-specific survival (DSS) and relapse-free survival (RFS), no statistically significant results were observed (HR = 1.573, 95%CI: 0.761-3.250, P = 0.222; HR = 1.432, 95%CI: 0.108-19.085, P = 0.786). Subgroup analysis demonstrated that high AEG-1 SI was significantly related to poor prognosis in esophageal squamous cell carcinoma (ESCC) (HR = 1.715, 95%CI: 1.211-2.410, P = 0.002), gastric carcinoma (GC) (HR = 2.255, 95%CI: 1.547-3.288, P<0.001), colorectal carcinoma (CRC) (HR = 2.922, 95%CI: 1.921-4.444, P<0.001), gallbladder carcinoma (GBC) (HR = 3.047, 95%CI: 1.685-5.509, P<0.001), hepatocellular carcinoma (HCC) (HR = 2.245, 95%CI: 1.620-3.113, P<0.001), pancreatic adenocarcinoma (PAC) (HR = 2.408, 95%CI: 1.625-3.568, P<0.001).
CONCLUSIONS: The current meta-analysis indicated that high AEG-1 SI might be associated with tumor progression and poor survival status in patients with gastrointestinal cancer. AEG-1 might play a vital role in promoting tumor aggression and could serve as a potential target for molecular treatments. Further clinical trials are needed to validate whether AEG-1 SI provides valuable insights into improving treatment decisions.

Gu C, Feng L, Peng H, et al.
MTDH is an oncogene in multiple myeloma, which is suppressed by Bortezomib treatment.
Oncotarget. 2016; 7(4):4559-69 [PubMed] Free Access to Full Article Related Publications
Metadherin (MTDH) is identified as an oncogene in multiple cancers including breast cancer, bladder cancer and endometrial cancer. However, the function of MTDH in multiple myeloma (MM) is still unexplored. In this study, we disclose that MTDH is an oncogene in MM. This is characterized by an elevation mRNA level of MTDH and chromosomal gain of MTDH locus in MM cells compared to normal samples. Moreover, MTDH expression significantly increased in MMSET translocation (MS) subgroup, one of the high-risk subgroups in MM, and was significantly correlated with MM patients' poor outcomes in Total Therapy 2 (TT2) cohort. Further knockdown of MTDH expression by shRNA in MM cells induced cell apoptosis, inhibited MM cells growth in vitro and decreased xenograft tumor formation in vivo. Interestingly, opposite to TT2, MM patients with high-MTDH expression showed favorable survival outcomes in the TT3 cohort, while Bortezomib treatment was the major difference between TT2 and TT3 cohort. Furthermore we proved that Bortezomib suppressed pre- and post-transcription levels of MTDH expression of MM cells in vitro and in vivo. Finally, our studies demonstrated that MTDH is a transcriptional gene of MMSET/NFκB /MYC signaling in MM cells, which is inhibited by Bortezomib treatment.

Zhou CX, Wang CL, Yu AL, et al.
MiR-630 suppresses breast cancer progression by targeting metadherin.
Oncotarget. 2016; 7(2):1288-99 [PubMed] Free Access to Full Article Related Publications
MicroRNAs have been integrated into tumorigenic programs as either oncogenes or tumor suppressor genes. The miR-630 was reported to be deregulated and involved in tumor progression of several human malignancies. However, its expression regulation shows diversity in different kinds of cancers and its potential roles remain greatly elusive. Herein, we demonstrate that miR-630 is significantly suppressed in human breast cancer specimens, as well as in various breast cancer cell lines. In aggressive MDA-MB-231-luc and BT549 breast cancer cells, ectopic expression of miR-630 strongly inhibits cell motility and invasive capacity in vitro. Moreover, lentivirus delivered miR-630 bestows MDA-MB-231-luc cells with the ability to suppress cell colony formation in vitro and pulmonary metastasis in vivo. Further studies identify metadherin (MTDH) as a direct target gene of miR-630. Functional studies shows that MTDH contributes to miR-630-endowed effects including cell migration and invasion as well as colony formation in vitro. Taken together, these findings highlight an important role for miR-630 in the regulation of metastatic potential of breast cancer and suggest a potential application of miR-630 in breast cancer treatment.

Li WF, Dai H, Ou Q, et al.
Overexpression of microRNA-30a-5p inhibits liver cancer cell proliferation and induces apoptosis by targeting MTDH/PTEN/AKT pathway.
Tumour Biol. 2016; 37(5):5885-95 [PubMed] Related Publications
Increasing results suggest microRNAs (miRNAs) could function important roles in malignant tumor progression. miR-30a-5p is downregulated in variety of cancers and acts as a cancer suppressing gene. The functions and molecular mechanisms of miRNA-30a-5p in hepatocellular carcinoma (HCC) remain unclear. In the present study, quantitative real-time PCR (qRT-PCR) was used to detect miR-30a-5p expression in 16 pairs of HCC and their adjacent non-cancerous tissues and HCC cell lines. By overexpression of miRNA-30a-5p, CCK-8 and colon formation assay were used to evaluate cell growth and flow cytometry to evaluate cell apoptosis. Western blot was used to test protein expression. And potential mechanisms were analyzed with luciferase activity assay. In vivo HepG2 tumor growth was observed with nude mice. Our results showed that miR-30a-5p expression in HCC tissues was significantly lower compared to adjacent non-cancerous liver tissues, and lower miR-30a-5p expression was also observed in HCC cell lines compared to normal liver cell. Luciferase assay showed that metadherin (MTDH) mRNA was a direct target of miR-30a-5p. A significant reverse correlation between miR-30a-5p and MTDH in liver cancer tissues was observed. miR-30a-5p overexpression in HCC cells significantly inhibited cell proliferation, colon formation, and induced apoptosis while MTDH overexpression reversed growth inhibition and apoptosis induction of miRNA-30a-5p in HCC cells. miRNA-30a-5p upregulated phosphatase and tensin homolog (PTEN) protein expression and thus inhibited AKT activating by targeting MTDH. miRNA-30a-5p also significantly inhibited HepG2 tumor growth in vivo. Our results suggest that underexpression of miR-30a-5p might function as a tumor suppressing miRNA by directly targeting MTDH in HCC and is therefore a potential candidate biomarker for HCC targeting therapy.

Zhu R, Tian Y
Astrocyte elevated gene-1 increases invasiveness of NSCLC through up-regulating MMP7.
Cell Physiol Biochem. 2015; 37(3):1187-95 [PubMed] Related Publications
BACKGROUND/AIMS: The aggressive manner of non-small cell lung cancer (NSCLC) cells accounts for the majority of the lethality of the disease. Recently, increased astrocyte elevated gene-1 (AEG-1) levels have been shown to closely correlate with poor prognosis of NSCLC, whereas the underlying mechanisms are not clear.
METHODS: We examined the AEG-1 and matrix metalloproteinase 7 (MMP7) levels in NSCLC tissues, compared to the paired adjacent non-tumor lung tissue. We modulated AEG-1 levels in NSCLC cells, and examined its effects on MMP7 levels by RT-qPCR, on cellular protein by Western blot, and on secreted protein by ELISA. We also examined the cell invasiveness in AEG-1-modified NSCLC cells in a transwell cell migration assay. We used specific signal pathway inhibitors to treat AEG-1-modified NSCLC cells and examined its effects on MMP7.
RESULTS: AEG-1 and MMP7 levels were both significantly increased in NSCLC tissues, compared to the paired adjacent non-tumor lung tissue. The AEG-1 and MMP7 levels were strongly correlated. Overexpression of AEG-1 in NSCLC cells significantly increased MMP7 levels and cell invasiveness, while AEG-1 depletion in NSCLC cells significantly decreased MMP7 levels and cell invasiveness. Application of a specific MAPK-p42/p44 inhibitor, but not application of specific inhibitors for MAPK-p38, PI3k/Akt, or JNK signaling pathways, to AEG-1-overexpressing NSCLC cells substantially abolished the AEG-1-mediated MMP7 up regulation.
CONCLUSION: AEG-1 promotes NSCLC cell invasiveness through MAPK-p42/p44-dependent activation of MMP7.

Tong L, Wang C, Hu X, et al.
Correlated overexpression of metadherin and SND1 in glioma cells.
Biol Chem. 2016; 397(1):57-65 [PubMed] Related Publications
Glioma is the most common primary brain tumor with poor prognosis. Effective treatment of glioma remains a big challenge due to complex pathogenic mechanisms. Previous studies have shown that metadherin (MTDH) and its interacting protein staphylococcal nuclease domain containing 1 (SND1) are overexpressed in many solid tumors. To elucidate the role of MDTH and SND1 in the pathogenesis of glioma, we examined the expression of MTDH and SND1 in primary glioma tissues and found that both MTDH and SND1 were highly expressed, with similar expression patterns. Co-expression of MTDH and SND1 was associated with advanced glioma grades. In addition, we detected the interaction between MTDH and SND1 in cultured glioma cell lines. MTDH could promote the expression of p65 and SND1 in glioma cells. However, enhanced SND1 expression by MTDH was abolished by the inhibition of p65. In conclusion, we demonstrated high expression levels MTDH and SND1 in primary glioma tissues. MTDH might promote glioma by inducing SND1 expression through the activation of NF-κB pathway. MTDH and SND1 may serve as the indicator of malignancy and prognosis as well as therapeutic targets for patients with glioma.

Li C, Wu X, Zhang W, et al.
AEG-1 Promotes Metastasis Through Downstream AKR1C2 and NF1 in Liver Cancer.
Oncol Res. 2014; 22(4):203-11 [PubMed] Related Publications
Liver cancer is one of the most lethal cancers, but our knowledge of the molecular mechanism underlying this process remains insufficient. Through deep sequencing and expression regulation analysis in liver cancer cells, we identified two novel factors, AKR1C2 (positive factor) and NF1 (negative factor), as the AEG-1 downstream players in the process of metastasis in liver cancer. They were experimentally validated to have the capacities of regulating cell migration, cell invasion, cell proliferation, and EMT. Further clinic expression and animal model evidence confirmed their functions. Together, our findings provide a new insight into the pharmaceutical and therapeutic use of AEG-1 and downstream AKR1C2 and NF1.

Yan JJ, Zhang YN, Liao JZ, et al.
MiR-497 suppresses angiogenesis and metastasis of hepatocellular carcinoma by inhibiting VEGFA and AEG-1.
Oncotarget. 2015; 6(30):29527-42 [PubMed] Free Access to Full Article Related Publications
Hepatocellular carcinoma (HCC) is a worldwide malignance and displays marked vascular abnormalities and active metastasis. MicroRNAs (miRNAs) have been shown to play important roles in regulating tumor properties in cancer, however, whether miR-497 contributes to HCC angiogenesis or metastasis remains unclear. In this study, we found that miR-497 was significantly down-regulated in HCC tissue samples and cell lines. Gain-of-function and loss-of-function studies revealed that miR-497 could repress both the pro-angiogenic and metastatic ability of HCC cells. Subsequent investigations disclosed that miR-497 directly inhibited the 3'-untranslated regions (UTRs) of vascular endothelial growth factor A (VEGFA) and astrocyte elevated gene-1 (AEG-1). Furthermore, overexpression of these targets antagonized the function of miR-497. Based on nude mouse models, we demonstrated that overexpression of miR-497 significantly repressed microvessel densities in xenograft tumors and reduced pulmonary metastasis. In conclusion, our findings indicate that miR-497 downregulation contributes to angiogenesis and metastasis in HCC.

Li C, Wu X, Zhang W, et al.
High-Content Functional Screening of AEG-1 and AKR1C2 for the Promotion of Metastasis in Liver Cancer.
J Biomol Screen. 2016; 21(1):101-7 [PubMed] Related Publications
Liver cancer is one of the most lethal cancer types in humans, but our understanding of the molecular mechanisms underlying this process remains insufficient. Here, we conducted high-content screening of the potential genes involved in liver cancer metastasis, which we selected from the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway database, based on the SAMcell method and RNA interference technology. We identified two powerful genes in the liver cancer metastasis process, AEG-1 and AKR1C2, both of which proved to be positive regulators in promoting metastasis in liver cancer. Further clinical results verified their roles in liver cancer. In summary, these findings could provide new insight into the liver cancer mechanism and potentially therapeutic novel targets for liver cancer therapies in the future.

Li WF, Ou Q, Dai H, Liu CA
Lentiviral-Mediated Short Hairpin RNA Knockdown of MTDH Inhibits Cell Growth and Induces Apoptosis by Regulating the PTEN/AKT Pathway in Hepatocellular Carcinoma.
Int J Mol Sci. 2015; 16(8):19419-32 [PubMed] Free Access to Full Article Related Publications
The activation of oncogenes and the loss of tumor suppressor genes are believed to play critical roles in the pathogenesis of human hepatocellular carcinoma (HCC). Metaherin(MTDH), also called astrocyte elevated gene-1 (AEG-1), is frequently amplified in a variety of cancers, but the roles of MTDH with regard to growth and apoptosis in HCC have not yet been studied. In the present study, we first analyzed the expression of MTDH in HCC samples. We found that MTDH protein levels are higher in most HCC cancerous tissues compared with their matched adjacent non-tumor tissues. Additionally, the MTDH mRNA was also higher inHCC tissues compared to their matched adjacent non-tumor tissues. Knockdown of the endogenous MTDH using small interfering RNA further showed that deficiency of MTDH suppressed cell growth and caused apoptosis in HCC cells. Knockdown MTDH promoted PTEN and p53 expression in HCC cells and inhibited AKT phosphorylation. Knockdown MTDH also inhibited tumor growth in vivo. All these results indicated that MTDH protein levels in most HCC tissues are higher than non-tumor tissues, and knockdown of MTDH inhibited growth and induced apoptosis in HCC cells through the activation of PTEN.Therefore, MTDH might be an effective targeted therapy gene for HCC.

Gollavilli PN, Kanugula AK, Koyyada R, et al.
AMPK inhibits MTDH expression via GSK3β and SIRT1 activation: potential role in triple negative breast cancer cell proliferation.
FEBS J. 2015; 282(20):3971-85 [PubMed] Related Publications
Recent studies have highlighted the involvement of metadherin (MTDH), an oncogenic protein, in promoting cancer progression, metastasis and chemoresistance in many cancers including mammary carcinomas. However, the molecular regulation of MTDH is still not completely understood. In this study we document that AMP activated protein kinase (AMPK) activation-induced anti-proliferative effects are, in part, mediated by inhibiting MTDH expression in MDA-MB-231 and BT-549 triple negative breast cancer (TNBC) cells. 5-Aminoimidazole-4-carboxamide ribonucleotide (AICAR), an AMPK activator, caused growth arrest, inhibition of migration and invasion of TNBC cells. Intriguingly, AICAR or metformin treatment resulted in significant downregulation of MTDH expression via inhibiting c-Myc expression. In contrast, treatment of cells with compound C, an inhibitor of AMPK, increased both c-Myc and MTDH expressions in TNBC cells. Also, AMPK activation caused increased glycogen synthase kinase 3β (GSK3β) activity by inhibiting the inactive phosphorylation at Ser9, on the one hand, and activation of sirtuin1 (SIRT1) by inhibiting Ser47 phosphorylation, as evidenced by deacetylation of p53, on the other hand. Moreover, AMPK-induced GSK3β and SIRT1 activities were found to be responsible for inhibiting c-Myc-mediated upregulation of MTDH, as LiCl (an inhibitor of GSK3β) and EX-527 (an inhibitor of SIRT1) reversed AICAR-mediated downregulation of c-Myc and MTDH expressions. Similar results were observed with siSIRT1 treatment. Furthermore, AICAR and EX-527 treatments caused increased cell death under MTDH-depleted conditions. Finally, we uncovered a novel regulation of MTDH expression and showed that AMPK activation by inducing GSK3β and SIRT1 downregulates MTDH expression via inhibiting c-Myc in TNBC cells.

Wang Y, Wei Y, Tong H, et al.
MiR-302c-3p suppresses invasion and proliferation of glioma cells via down-regulating metadherin (MTDH) expression.
Cancer Biol Ther. 2015; 16(9):1308-15 [PubMed] Free Access to Full Article Related Publications
Glioma is the most common malignant brain tumors with poor prognosis. The molecular events involved in the development and progression of glioma remain unclear. In this study, the expression levels of miR-302c-3p were examined in glioma tissues by qRT-PCR. The in vitro and in vivo functional effects of miR-302c-3p were examined further. Luciferase reporter assays were conducted to confirm the targeting associations. Results showed that the expression level of miR-302c-3p in glioma tissues was significantly lower than those in normal brain tissues (P < 0.001). The decreased expression of mi-302c-3p in glioma was positively associated with WHO grade (P < 0.001). Up-regulation of MTDH was also detected in glioma tumors compared with normal brain tissues (P = 0.0027) and is inversely correlated with miR-302c-3p expression (P = 0.003, R(2) = 0.4065). MTDH mRNA is a direct target of miR-302c-3p, whose ectopic expression decreases MTDH expression through binding to its 3'-untranslated region. Overexpression of miR-302c-3p results in a dramatic inhibition of glioma cells proliferation and invasion in vitro and in vivo. These data suggest that miR-302c-3p play a pivotal role in the progression of glioma by targeting MTDH and is a potential inhibitor in glioma treatment.

Zhang J, Zhu D, Lv Q, et al.
The key role of astrocyte elevated gene-1 in CCR6-induced EMT in cervical cancer.
Tumour Biol. 2015; 36(12):9763-7 [PubMed] Related Publications
In recent years, astrocyte elevated gene-1 (AEG-1) has been recommended as an important mediator that is involved in the epithelial-to-mesenchymal transition (EMT) process. However, the mechanisms underlying the chemokine (C-C motif) ligand 20 (CCL20)/chemokine (C-C motif) receptor 6 (CCR6)-AEG-1 pathway-mediated EMT in cervical cancer (CC) have not been well featured till now. We used immunohistochemistry and immunoblotting to assess the expression of AEG-1 in 94 cervical cancer tissues and cells. Subsequently, cervical cancer SiHa cells were treated with si-AEG-1 and then subjected to in vitro assays. We observed that AEG-1 proteins were highly expressed in cervical cancer tissues and closely correlated with International Federation of Gynecology and Obstetrics (FIGO) stage and metastasis. Importantly, we validated the expression of AEG-1, p-Erk1/2, p-Akt, vimentin, N-cadherin, and matrix metalloproteinase 2 (MMP2) increased in SiHa with CCL20 treatment in a concentration-dependent manner. When cells were treated with si-AEG-1, the expression of p-Erk1/2, p-Akt, vimentin, N-cadherin, and MMP2 was also downregulated. Using the cell cycle assay, the knockdown of AEG-1 inhibited the entry of G1 into S phase. In conclusion, AEG-1 mediates CCL20/CCR6-induced EMT development via both Erk1/2 and Akt signaling pathway in cervical cancer, which indicates that CCL20/CCR6-AEG-1-EMT pathway could be suggested as a useful target to affect the progression of cervical cancer.

Fang C, Shen Y, Qi P, et al.
Astrocyte-elevated gene-1 mediates insulin-like growth factor 1-induced the progression of cardiac myxoma.
Tumour Biol. 2015; 36(12):9769-77 [PubMed] Related Publications
Recently, astrocyte-elevated gene-1 (AEG-1) and insulin-like growth factor 1 (IGF-1) have been involved in the regulation of multiple signaling pathways in tumorigenesis. To date, the detailed mechanisms underlying IGF-1-AEG-1 pathway-induced proliferation and apoptosis in cardiac myxoma (CM) was not reported. In the present study, we used immnohistochemistry, immunoblotting, and qRT-PCR to detect the expression profile of IGF-1 and AEG-1 in 90 CM tissues, and then cultured CM cells were subjected to si-AEG-1, in vitro, and in vivo assays. Our findings showed that IGF-1 and AEG-1 were obviously upregulated in CM tissues and markedly associated with tumor size. When CM cells were treated with si-AEG-1, si-AEG-1 attenuated IGF-1-induced CM cell growth and enhanced cell apoptosis. Mechanically, we validated the expression of AEG-1, p-Erk1/2, and p-Akt increased in CM cells in response to IGF-1 treatment in a time-dependent manner. However, si-AEG-1 affected the expression of these proteins. Functionally, we found the knockdown of AEG-1-inhibited G1/S transition and tumor formation of CM cells. In conclusion, AEG-1 regulates IGF-1-induced proliferation and apoptosis via Erk1/2 and Akt signaling in CM development, which suggests IGF-1-AEG-1 signaling could be recommended to be a useful target to exert anti-tumor effects on CM.

Liang Y, Hu J, Li J, et al.
Epigenetic Activation of TWIST1 by MTDH Promotes Cancer Stem-like Cell Traits in Breast Cancer.
Cancer Res. 2015; 75(17):3672-80 [PubMed] Related Publications
Cancer stem-like cells (CSC) are a cell subpopulation that can reinitiate tumors, resist chemotherapy, and give rise to metastases. Metadherin (MTDH) contributes widely to tumor growth, drug resistance, relapse, and metastasis, but its molecular mechanisms of action are not well understood. Here, we report that MTDH drives CSC expansion by promoting the expression of TWIST1, a transcription factor critical for cancer cell stemness and metastasis. MTDH activates TWIST1 expression indirectly by facilitating histone H3 acetylation on the TWIST1 promoter, a process mediated by the histone acetyltransferase CBP. Mechanistic investigations showed that MTDH interacts with CBP and prevents its ubiquitin-mediated degradation, licensing its transcriptional activation of TWIST1. In clinical specimens of breast cancer, MTDH expression correlates positively with TWIST1 expression and CSC abundance. Overall, our work revealed that MTDH promotes CSC accumulation and breast tumorigenicity by regulating TWIST1, deepening the understanding of MTDH function in cancer.

Shi P, Fang C, Pang X
Astrocyte elevated gene-1 regulates CCL3/CCR5-induced epithelial-to-mesenchymal transition via Erk1/2 and Akt signaling in cardiac myxoma.
Oncol Rep. 2015; 34(3):1319-26 [PubMed] Related Publications
In recent years, astrocyte elevated gene-1 (AEG-1) has been reported as a key mediator that is involved in the epithelial-to-mesenchymal transition (EMT) process. However, the mechanisms underlying CCL3/CCR5-AEG-1 pathway-mediated EMT in cardiac myxoma (CM) has not been well featured till now. We used immnohistochemistry and immunoblotting to assess the expression of CCR5 and AEG-1 in 30 cases of CM tissues and cells. Subsequently, cultured CM cells were treated with si-AEG-1 or si-CCR5 and then subjected to in vitro assays. We observed that CCR5 and AEG-1 proteins were highly expressed in CM tissues (73.3 and 76.7%, respectively) and closely correlated with tumor size (>5 cm). Importantly, we validated the expression of AEG-1, p-Erk1/2, p-Akt, vimentin, N-cadherin and MMP2 increased in the CM cell with CCL3 treatment in a time- and concentration-dependent manner. When CM cells were treated with si-CCR5, the expression of AEG-1, p-Erk1/2, p-Akt, vimentin, N-cadherin and MMP2 was downregulated. In addition, when CM cells were treated with si-AEG-1, the expression of p-Erk1/2, p-Akt, vimentin, N-cadherin and MMP2 was also downregulated. Using the cell cycle and proliferation assay, the knockdown of AEG-1 inhibited the entry of G1 into S phase and the proliferation capacity of CM cells. In conclusion, AEG-1 mediates CCL3/CCR5-induced EMT development via both Erk1/2 and Akt signaling pathway in CM patients, which indicates CCL3/CCR5-AEG-1-EMT pathway could be suggested as a useful target to affect the progression of CM.

Zhao H, Wang QT, Geng SQ, et al.
PROTEIN EXPRESSION OF METADHERIN AND SENSIBILITY OF BREAST CANCER MDA-MB-231 CELLS TO TREATMENT BEFORE AND AFTER TRANSFECTION.
J Biol Regul Homeost Agents. 2015 Apr-Jun; 29(2):459-64 [PubMed] Related Publications
Breast cancer tends to have an increasing mortality, severely threatening the health of females. The invasion and metastasis of breast cancer are the leading causes of death. It has been reported that breast cancer is caused by the activation of a series of proto-oncogenes and inactivation of anti-oncogenes. In the present study, Real-time PCR and Western blot were used to detect the protein expression level of metadherin before and after transfecting MDA-MB-231 cells to identify the effect, while the sensitivity of MDA-MB-231 cells to 1 mg/L doxorubicin and 8mg/L taxol was measured by methylthiazolyldiphenyl-tetrazolium bromide (MTT). The results demonstrated that mRNA and protein expression level of metadherin both improved after transfection. The inhibition effect of 1 mg/L doxorubicin and 8 mg/L taxol on breast cancer cells decreased after transfection. Detected by flow cytometry, the apoptosis rate of breast cancer cells was 39.68±0.42%, 20.64±0.55%, respectively, under the effect of 1 mg/L doxorubicin; while under the effect of 8 mg/L taxol, the rate was 24.89±0.41% and 13.8±0.63%, respectively. Thus the inhibition effects of 1 mg/L doxorubicin and 8mg/L taxol to breast cancer cells and their effects on apoptosis were different, and the differences were statistically significant (P<0.05). Based on the statistics on the expression level of metadherin after transfecting breast cancer cells MDA-MB-231 and the exploration of the sensitivity of the cells to treatment, the effect of metadherin on breast cancer MDA-MB-232 cells was proved.

Rajasekaran D, Srivastava J, Ebeid K, et al.
Combination of Nanoparticle-Delivered siRNA for Astrocyte Elevated Gene-1 (AEG-1) and All-trans Retinoic Acid (ATRA): An Effective Therapeutic Strategy for Hepatocellular Carcinoma (HCC).
Bioconjug Chem. 2015; 26(8):1651-61 [PubMed] Free Access to Full Article Related Publications
Hepatocellular carcinoma (HCC) is a fatal cancer with no effective therapy. Astrocyte elevated gene-1 (AEG-1) plays a pivotal role in hepatocarcinogenesis and inhibits retinoic acid-induced gene expression and cell death. The combination of a lentivirus expressing AEG-1 shRNA and all-trans retinoic acid (ATRA) profoundly and synergistically inhibited subcutaneous human HCC xenografts in nude mice. We have now developed liver-targeted nanoplexes by conjugating poly(amidoamine) (PAMAM) dendrimers with polyethylene glycol (PEG) and lactobionic acid (Gal) (PAMAM-PEG-Gal) which were complexed with AEG-1 siRNA (PAMAM-AEG-1si). The polymer conjugate was characterized by (1)H-NMR, MALDI, and mass spectrometry; and optimal nanoplex formulations were characterized for surface charge, size, and morphology. Orthotopic xenografts of human HCC cell QGY-7703 expressing luciferase (QGY-luc) were established in the livers of athymic nude mice and tumor development was monitored by bioluminescence imaging (BLI). Tumor-bearing mice were treated with PAMAM-siCon, PAMAM-siCon+ATRA, PAMAM-AEG-1si, and PAMAM-AEG-1si+ATRA. In the control group the tumor developed aggressively. ATRA showed little effect due to high AEG-1 levels in QGY-luc cells. PAMAM-AEG-1si showed significant reduction in tumor growth, and the combination of PAMAM-AEG-1si+ATRA showed profound and synergistic inhibition so that the tumors were almost undetectable by BLI. A marked decrease in AEG-1 level was observed in tumor samples treated with PAMAM-AEG-1si. The group treated with PAMAM-AEG-1si+ATRA nanoplexes showed increased necrosis, inhibition of proliferation, and increased apoptosis when compared to other groups. Liver is an ideal organ for RNAi therapy and ATRA is an approved anticancer agent. Our exciting observations suggest that the combinatorial approach might be an effective way to combat HCC.

Zhu HD, Liao JZ, He XX, Li PY
The emerging role of astrocyte-elevated gene-1 in hepatocellular carcinoma (Review).
Oncol Rep. 2015; 34(2):539-46 [PubMed] Related Publications
Hepatocellular carcinoma (HCC) is the fifth most common malignancy worldwide, yet effective treatment for this disease is lacking. Thus, there is an urgent need to identify novel therapeutic targets for this dreadful disease. Numerous studies have established that overexpression of astrocyte-elevated gene-1 (AEG-1) is frequently observed in multiple types of cancers including HCC, and its expression levels are correlated with the stage and grade of the disease. Further studies revealed that AEG-1 plays a key role in several crucial aspects of HCC progression, including growth, transformation, cell survival, invasion, metastasis and chemoresistance. Moreover, AEG-1 overexpression activates the Wnt/β-catenin, mitogen-actived protein kinase (MAPK), nuclear factor (NF)-κB, and PI3K/Akt signaling pathways, and promotes its downstream gene expression to facilitate malignant potential. Recently, transgenic mice with hepatocyte-specific expression of AEG-1 (Alb/AEG-1) and AEG-1-knockout mouse both revealed novel aspects of the functions of AEG-1 in an in vivo context. This review evaluates the multi-functions of AEG-1 and describes the major signaling pathways and molecular alterations regulated by AEG-1 in HCC, indicating its key roles and potential as a biomarker or significant target for the therapy of HCC.

Wang B, Shen ZL, Jiang KW, et al.
MicroRNA-217 functions as a prognosis predictor and inhibits colorectal cancer cell proliferation and invasion via an AEG-1 dependent mechanism.
BMC Cancer. 2015; 15:437 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Recent studies have indicated the possible function of miR-217 in tumorigenesis. However, the roles of miR-217 in colorectal cancer (CRC) are still largely unknown.
METHODS: We examined the expression of miR-217 and AEG-1 in 50 CRC tissues and the corresponding noncancerous tissues by qRT-PCR. The clinical significance of miR-217 was analyzed. CRC cell lines with miR-217 upregulation and AEG-1 silencing were established and the effects on tumor growth in vitro and in vivo were assessed. Dual-luciferase reporter gene assays were also performed to investigate the interaction between miR-217 and AEG-1.
RESULTS: Our data demonstrated that miR-217 was significantly downregulated in 50 pairs of colorectal cancer tissues. MiR-217 expression levels were closely correlated with tumor differentiation. Moreover, decreased miR-217 expression was also associated with shorter overall survival of CRC patients. MiR-217 overexpression significantly inhibited proliferation, colony formation and invasiveness of CRC cells by promoting apoptosis and G0/G1 phase arrest. Interestingly, ectopic miR-217 expression decreased AEG-1 expression and repressed luciferase reporter activity associated with the AEG-1 3'-untranslated region (UTR). AEG-1 silencing resulted in similar biological behavior changes to those associated with miR-217 overexpression. Finally, in a nude mouse xenografted tumor model, miR-217 overexpression significantly suppressed CRC cell growth.
CONCLUSIONS: Our findings suggest that miR-217 has considerable value as a prognostic marker and potential therapeutic target in CRC.

Song Z, Wang Y, Li C, et al.
Molecular Modification of Metadherin/MTDH Impacts the Sensitivity of Breast Cancer to Doxorubicin.
PLoS One. 2015; 10(5):e0127599 [PubMed] Free Access to Full Article Related Publications
BACKGROUND: Breast cancer is a leading cause of death in women and with an increasing worldwide incidence. Doxorubicin, as a first-line anthracycline-based drug is conventional used on breast cancer clinical chemotherapy. However, the drug resistances limited the curative effect of the doxorubicin therapy in breast cancer patients, but the molecular mechanism determinants of breast cancer resistance to doxorubicin chemotherapy are not fully understood. In order to explore the association between metadherin (MTDH) and doxorubicin sensitivity, the differential expressions of MTDH in breast cancer cell lines and the sensitivity to doxorubicin of breast cancer cell lines were investigated.
METHODS: The mRNA and protein expression of MTDH were determined by real-time PCR and Western blot in breast cancer cells such as MDA-MB-231, MCF-7, MDA-MB-435S, MCF-7/ADR cells. Once MTDH gene was knocked down by siRNA in MCF-7/ADR cells and overexpressed by MTDH plasmid transfection in MDA-MB-231 cells, the cell growth and therapeutic sensitivity of doxorubicin were evaluated using MTT and the Cell cycle assay and apoptosis rate was determined by flow cytometry.
RESULTS: MCF-7/ADR cells revealed highly expressed MTDH and MDA-MB-231 cells had the lowest expression of MTDH. After MTDH gene was knocked down, the cell proliferation was inhibited, and the inhibitory rate of cell growth and apoptosis rate were enhanced, and the cell cycle arrest during the G0/G1 phase in the presence of doxorubicin treatment. On the other hand, the opposite results were observed in MDA-MB-231 cells with overexpressed MTDH gene.
CONCLUSION: MTDH gene plays a promoting role in the proliferation of breast cancer cells and its high expression may be associated with doxorubicin sensitivity of breast cancer.

Srivastava J, Robertson CL, Gredler R, et al.
Astrocyte Elevated Gene-1 (AEG-1) Contributes to Non-thyroidal Illness Syndrome (NTIS) Associated with Hepatocellular Carcinoma (HCC).
J Biol Chem. 2015; 290(25):15549-58 [PubMed] Free Access to Full Article Related Publications
Non-thyroidal illness syndrome (NTIS), characterized by low serum 3,5,3'-triiodothyronine (T3) with normal l-thyroxine (T4) levels, is associated with malignancy. Decreased activity of type I 5'-deiodinase (DIO1), which converts T4 to T3, contributes to NTIS. T3 binds to thyroid hormone receptor, which heterodimerizes with retinoid X receptor (RXR) and regulates transcription of target genes, such as DIO1. NF-κB activation by inflammatory cytokines inhibits DIO1 expression. The oncogene astrocyte elevated gene-1 (AEG-1) inhibits RXR-dependent transcription and activates NF-κB. Here, we interrogated the role of AEG-1 in NTIS in the context of hepatocellular carcinoma (HCC). T3-mediated gene regulation was analyzed in human HCC cells, with overexpression or knockdown of AEG-1, and primary hepatocytes from AEG-1 transgenic (Alb/AEG-1) and AEG-1 knock-out (AEG-1KO) mice. Serum T3 and T4 levels were checked in Alb/AEG-1 mice and human HCC patients. AEG-1 and DIO1 levels in human HCC samples were analyzed by immunohistochemistry. AEG-1 inhibited T3-mediated gene regulation in human HCC cells and mouse hepatocytes. AEG-1 overexpression repressed and AEG-1 knockdown induced DIO1 expression. An inverse correlation was observed between AEG-1 and DIO1 levels in human HCC patients. Low T3 with normal T4 was observed in the sera of HCC patients and Alb/AEG-1 mice. Inhibition of co-activator recruitment to RXR and activation of NF-κB were identified to play a role in AEG-1-mediated down-regulation of DIO1. AEG-1 thus might play a role in NTIS associated with HCC and other cancers.

He J, Cao Y, Su T, et al.
Downregulation of miR-375 in aldosterone-producing adenomas promotes tumour cell growth via MTDH.
Clin Endocrinol (Oxf). 2015; 83(4):581-9 [PubMed] Related Publications
OBJECTIVE: Previous studies have investigated the genetic and molecular basis of primary aldosteronism (PA), a common cause of human hypertension, but the effects of microRNAs (miRNAs) on the adrenocortical cell proliferation and aldosterone production are largely obscure. Here, we characterized miRNA expression patterns in the subtypes of PA to gain a better understanding of its pathogenesis.
METHODS: miRNA expression was assessed by microarray profiling analysis in aldosterone-producing adenoma (APA), unilateral adrenal hyperplasia (UAH) and normal adrenal cortex tissues. Selected differentially expressed miRNAs were further validated in a validation cohort by qRT-PCR. A gain-of-function approach was used to explore the functional role of the specific miRNA in vitro.
RESULTS: Of 31 miRNAs including miR-375, miR-7 and miR-29b were found to be significantly differentially expressed among these three groups. miR-375 was the most downregulated one in adrenal cortex tissues from PA patients, and its expression level was inversely correlated with the tumour size in APA. Overexpression of miR-375 in a human adrenocortical cell line (H295R) reduced cell proliferation and suppressed the expression of MTDH (metadherin, also known as astrocyte elevated gene-1). Moreover, MTDH was verified as a direct target of miR-375 through luciferase reporter assays. Knock-down of MTDH in H295R cells attenuated Akt-Ser473 phosphorylation and inhibited cell viability.
CONCLUSION: Our findings suggest that miR-375 exerts its tumour-suppressive function via targeting MTDH/Akt pathway and implicate a potential therapeutic target in PA.

Disclaimer: This site is for educational purposes only; it can not be used in diagnosis or treatment.

Cite this page: Cotterill SJ. MTDH, Cancer Genetics Web: http://www.cancer-genetics.org/MTDH.htm Accessed:

Creative Commons License
This page in Cancer Genetics Web by Simon Cotterill is licensed under a Creative Commons Attribution-ShareAlike 4.0 International License.
Note: content of abstracts copyright of respective publishers - seek permission where appropriate.

 [Home]    Page last revised: 15 March, 2017     Cancer Genetics Web, Established 1999