Forkhead box M1 (FOXM1) is overexpressed and activates numerous oncoproteins in tumors. However, the mechanism by which the FOXM1 protein aberrantly accumulates in human cancer remains uncertain. This study was designed to clarify the upstream signaling pathway(s) that regulate FOXM1 protein stability and transcriptional activity.

Mass spectrometry and immunoprecipitation were performed to identify the FOXM-metadherin (MTDH) interaction. In vivo and in vitro ubiquitination assays were conducted to test the effect of MTDH on FOXM1 stability. Chromatin immunoprecipitation assays were used to determine the involvement of MTDH in FOXM1 transcriptional activity. Cell invasion assays, tube formation assays, and in vivo tumor formation assays were performed to evaluate the cooperative activities of FOXM1 and MTDH during tumorigenesis.

MTDH directly interacts with FOXM1 via the N-terminal inhibitory domain of MTDH, and this interaction disrupted the binding of cadherin-1 to FOXM1, thus protecting FOXM1 from subsequent proteasomal degradation. Deleting the MTDH-binding sites of FOXM1 abolished the MTDH overexpression-mediated stabilization of FOXM1. MTDH also bound to FOXM1 target gene promoters and enhanced FOXM1 transcriptional activity. MTDH knockdown destabilized FOXM1 and attenuated its transcriptional activity, consequently inhibiting cell cycle progression, angiogenesis, and cancer cell invasion in vitro and in vivo; these effects were abolished via forced overexpression of a stabilized mutant form of FOXM1. Thus, MTDH stabilized FOXM1 and supported the sustained activation of FOXM1 target genes.

These findings highlight a novel MTDH-regulated mechanism of FOXM1 stabilization and provide profound insight into the tumorigenic events simultaneously mediated by FOXM1 and MTDH.

Altered expression of many genes and proteins is essential for cancer development and progression. Recently, the affected expression of metadherin (MTDH), also known as AEG-1 (Astrocyte Elevated Gene 1) and Lyric, has been implicated in various aspects of cancer progression and metastasis. Elevated expression of MTDH/AEG-1 has been reported in many cancers including breast, prostate, liver, and esophageal cancers, whereas its expression is low or absent in non-malignant tissues. These expression studies suggest that MTDH may represent a potential tumor associated antigen. MTDH also regulates multiple signaling pathways including PI3K/Akt, NF-κB, Wnt/β-catenin, and MAPK which cooperate to promote the tumorigenic and metastatic potential of transformed cells. Several microRNA have also been found to be associated with the increased MTDH expression in different cancers. Increased MTDH levels were linked to the tumor chemoresistance making it an attractive novel therapeutic target. In this review, we summarize data on MTDH function in various cancers.

Diabetic kidney disease (DKD) is the principal cause of end-stage renal disease worldwide and few treatments are available. Because immunomodulators are pivotal to DKD pathophysiology, anti-inflammatory agents may be useful for treating DKD. This study was conducted to investigate the effect of micheliolide (MCL), a novel guaianolide sesquiterpene lactone with well-known anti-inflammatory effects, on DKD. Treatment with dimethylaminomicheliolide (DMAMCL), the pro-drug of MCL currently under clinical trial in oncology, protected the kidneys against proteinuria, renal failure, histopathological injury, and inflammation in db/db mice. This effect was associated with metadherin (Mtdh) downregulation. We observed aberrant upregulation of Mtdh in the kidneys of db/db mice and high-glucose (HG)-induced mouse tubular epithelial cells (mTECs). Downregulation of Mtdh obviously inhibited nuclear factor-κB signaling activation and suppressed its downstream inflammatory cytokines, such as monocyte chemotactic peptide-1, interleukin-1β, tumor necrosis factor-α, and interleukin-6 in HG-induced mTECs, which was similar to the effect of MCL. Mtdh overexpression largely reversed the anti-inflammatory role of MCL. Moreover, MCL downregulated Mtdh by both inhibiting the transcription level and promoting ubiquitin-mediated degradation. These findings suggest that DMAMCL is a promising anti-inflammatory agent useful for preventing renal injury in DKD by inhibiting Mtdh-mediated renal inflammation.

Resistance to chemotherapy and radiation therapy is considered a major therapeutic barrier in breast cancer. Cancer stem cells (CSCs) play a prominent role in chemo and radiotherapy resistance. The established chemo and radio-resistant triple-negative breast cancer (TNBC) cell line MDA-MB-231/IR displays greater CSC characteristics than the parental MDA-MB-231 cells. Escalating evidence demonstrates that metadherin (MTDH) is associated with a number of cancer signaling pathways as well as breast cancer therapy resistance, making it an attractive therapeutic target. Kaplan-Meier plot analysis revealed a correlation between higher levels of MTDH and shorter lifetimes in breast cancer and TNBC patients. Moreover, there was a positive correlation between the MTDH and CD44 expression levels in The Cancer Genome Atlas breast cancer database. We demonstrate that MTDH plays a pivotal role in the regulation of stemness in MDA-MB-231/IR cells. Knockdown of MTDH in MDA-MB-231/IR cells resulted in a reduction in the CSC population, aldehyde dehydrogenase activity, and major CSC markers, including β-catenin, CD44⁺, and Slug. In addition, MTDH knockdown increased reactive oxygen species (ROS) levels in MDA-MB-231/IR cells. We found that phenethyl isothiocyanate (PEITC), a well-known pro-oxidant phytochemical, suppressed stemness in MDA-MB-231/IR cells through ROS modulation via the downregulation of MTDH. Co-treatment of PEITC and N-Acetylcysteine (a ROS scavenger) caused alterations in PEITC induced cell death and CSC markers. Moreover, PEITC regulated MTDH expression at the post-transcriptional level, which was confirmed using cycloheximide, a protein synthesis inhibitor.

Giant cell tumor of bone (GCTB) is a benign but locally aggressive tumor, which can cause significant bone destruction at the epiphysis of long bones. Recent studies have demonstrated that norcantharidin (NCTD) can inhibit the proliferation and migration of various human cancer cells, but the role of NCTD in GCTB has not previously been evaluated. The aim of this study was to explore the nature of the anti-cancer effects of NCTD in GCTB and to elucidate the biomolecular mechanisms responsible for these effects. Primary stromal cell cultures, representing the main neoplastic component of GCTB, were used for cell-based experiments. Firstly, the anti-cancer effects of NCTD on GCTB stromal tumor cells were investigated by CCK-8 assay, flow cytometry and transwell invasion assay. Next, microRNA (miRNA) microarray and quantitative reverse transcription PCR (qRT-PCR) analyses were performed to examine and verify altered expression of miRNAs associated with NCTD treatment. Subsequently, the GCTB stromal cells were transfected with miR-30a inhibitor to confirm its involvement in the observed anti-cancer effects of NCTD. Luciferase reporter assays were carried out to identify the target gene of miR-30a. Moreover, changes in the expression of protein markers of AKT signaling were measured by Western Blot analysis. The results demonstrated that NCTD treatment could inhibit cell proliferation, block the cell cycle process and induce cell apoptosis in GCTB stromal cells. An inhibitory effect of NCTD on GCTB stromal cell invasion through inhibition of epithelial mesenchymal transition (EMT) was also observed. Expression of miR-30a was significantly upregulated by NCTD treatment and miR-30a knockdown significantly reversed the anti-tumor effects of NCTD against GCTB stromal cells. Of note, metadherin (MTDH), a novel oncogene which modulates the AKT pathway, was identified as a direct target of miR-30a in GCTB stromal cells. Further data showed that miR-30a could negatively regulate the expression of MTDH and the AKT pathway in GCTB stromal cells. Importantly, MTDH expression was found to be inversely correlated with miR-30a expression in clinical GCTB specimens. Moreover, NCTD treatment effectively suppressed the AKT signaling pathway as demonstrated by downregulation of phosphorylated-Akt S473 (p-Akt S473), p-Akt (T308), phosphorylated-glycogen synthase kinase (GSK)3β (p-GSK3β) and c-Myc, whilst miR-30a inhibition re-activated the AKT signaling pathway in GCTB stromal cells. Our findings demonstrate that NCTD can inhibit cell proliferation and metastasis of GCTB stromal cells in vitro, via modulating the miR-30a/MTDH/AKT signaling axis. This suggests that NCTD has potential as a novel therapeutic treatment for GCTB.

Long non-coding RNAs (lncRNAs) have recently emerged as key regulators of the occurrence and progression of various human cancers, including colorectal cancer. However, the regulatory mechanism of lncRNAs in the tumorigenesis of colorectal cancer remains poorly understood. In this study, we aimed to elucidate the potential role of lncRNA HCG18 in colorectal cancer. Herein, we found that HCG18 expression was significantly upregulated in colorectal cancer tissues and cell lines. Knockdown of HCG18 significantly inhibited the growth and invasion of colorectal cancer cells, while its overexpression had the opposite effect. Moreover, HCG18 was identified as a sponge of miR-1271. Our results showed that knockdown of HCG18 markedly upregulated miR-1271 expression in colorectal cancer cells. Notably, HCG18 expression was inversely correlated with miR-1271 expression in colorectal cancer specimens. Further investigation revealed that HCG18 contributed to the enhancement of MTDH/Wnt/β-catenin signaling in colorectal cancer cells. The antitumor effect of HCG18 inhibition was significantly reversed by miR-1271 inhibition or MTDH overexpression. Overall, the results of our study demonstrate that HCG18 exerts a potential oncogenic function in colorectal cancer by enhancing MTDH/Wnt/β-catenin signaling via sponging of miR-1271, highlighting the importance of HCG18/miR-1271/ MTDH/Wnt/β-catenin signaling in the progression of colorectal cancer.

Cisplatin (CDDP)-based chemotherapy is the gold standard treatment for many types of cancer. However, the phenotypic hallmark of tumors often changes after CDDP treatment, with the acquisition of epithelial-to-mesenchymal transition (EMT) and platinum resistance. Furthermore, the mechanisms by which cancer cells acquire EMT under the control of CDDP remain unclear. Following an investigation of urothelial carcinoma (UC) before and after the acquisition of platinum resistance, we offer the new target TNFAIP2, which led to EMT and tumor invasion in platinum-treated UC cells. TNFAIP2 expression in cancer was examined at the protein and transcriptional levels. A potential target for TNFAIP2 during EMT was assessed by microarray. Clinically, upregulated TNFAIP2 expression was identified as a significant predictor of mortality following surgery in three different cohorts of patients with UC (n = 156, n = 119, and n = 54). Knockdown of TNFAIP2 resulted in upregulation of E-cadherin expression and downregulation of TWIST1 expression, which decreased motile function in platinum-resistant UC cells. TNFAIP2 overexpression led to downregulation of E-cadherin expression and upregulation of TWIST1 expression in platinum-naïve UC cells. Clinical investigation of matched pre- and post-CDDP-treated UC sections confirmed upregulation of TNFAIP2 expression in CDDP-treated tumors but downregulation of E-cadherin expression. Global gene expression analysis following TNFAIP2 knockdown identified MTDH as a positive regulator of TNFAIP2-derived EMT acquisition in cancer cells. The present results suggest a relationship between TNFAIP2 and EMT in cancers under the control of CDDP, in which MTDH expression levels in cancer cells are vital for promoting TNFAIP2-derived EMT acquisition.

Metastasis of ovarian cancer is regulated by microRNAs. This study focused on the effects of miR-30a-5p on ovarian cancer migration and invasion. Our results showed that the miR-30a-5p and mucin type O-glycan biosynthesis are closely related to ovarian cancer, and that miR-30a-5p was downregulated in ovarian cancer cells. miR-30a-5p overexpression reduced cell viability and inhibited migration and invasion in HO-8910 and HO-8910PM cells. S phase kinase-associated protein 2 (SKP2), B cell lymphoma 9 (BCL9), and NOTHC1 are direct target genes of miR-30a-5p. MTDH, SKP2, BCL9, and NOTCH1 genes were overexpressed in ovarian cancer cells, and they are direct target genes of miR-30a-5p. miR-30a-5p overexpression inhibited epithelial-mesenchymal transition (EMT) process, while upregulation of SKP2, BCL9, and NOTCH1 gene expression levels reduced the inhibition of EMT process by miR-30a-5p. miR-30a-5p was lowly expressed in ovarian cancer, and such a phenomenon is related to ovarian cancer metastasis. miR-30a-5p might inhibit the migration and invasion of ovarian cancer cells by downregulating the expression of SKP2, BCL9, and NOTCH1 genes.

Cervical cancer is one of the most common female malignancies worldwide. Emerging data have shown that microRNAs (miRNAs) play significant roles in various human cancers, including cervical cancer. Aberrantly expressed miRNAs in cervical cancer contribute to tumour occurrence and development as either tumour suppressors or promoters. Research suggests that miRNA-433 (miR-433) possibly plays an important role in the development of various cancer types. However, no study has explored the expression patterns, roles and underlying mechanisms of miR-433 in cervical cancer. In the present study, we demonstrated significant downregulation of miR-433 in cervical cancer tissues and cell lines. Low miR-433 expression was found to significantly correlate with patient characteristics including tumour size, International Federation of Gynecology and Obstetrics stage, lymph node and distant metastases. Functional studies showed that restoration of miR-433 inhibited cell proliferation and invasion and increased apoptosis in cervical cancer cells. Metadherin (MTDH) was also validated as a direct target gene of miR-433. MTDH mRNA expression was upregulated in cervical cancer tissues and was inversely correlated with miR-433 expression. MTDH knockdown showed similar tumour-suppressive roles as miR-433 overexpression in regards to cervical cancer cell proliferation, invasion and apoptosis. Rescue experiments revealed that MTDH overexpression markedly reversed the effects of miR-433 overexpression in regards to proliferation, invasion and apoptosis of cervical cancer cells. Further investigations revealed that miR-433 inactivated AKT and β-catenin pathways in cervical cancer. Collectively, these findings indicate the essential roles of miR-433 in suppressing cervical cancer progression and suggest its potential as a therapeutic target for the treatment of cervical cancer.

GABAA-receptor-associated protein like-1 (GABARAPL1) is involved in a variety of cancers. The purpose of this study was to investigate the expression, prognostic roles and functions of GABARAPL1 in triple negative breast cancer (TNBC). Quantitative real-time PCR (qRT-PCR) showed that GABARAPL1 was up regulated in both TNBC cell lines and clinical TNBC tissues. High GABARAPL1 expression level was associated with shorter overall survival (OS) and disease free survival (DFS). Furthermore, inhibition of GABARAPL1 suppressed cell proliferation, tumorigenesis, invasion and metastasis, and induced cell apoptosis. We found that metadherin (MTDH) was a downstream target of GABARAPL1. Inhibition of GABARAPL1 suppressed the mRNA and protein expression of MTDH, and overexpression of MTDH could reverse the effects of GABARAPL1 inhibition, which meant GABARAPL1 performed its function partly through MTDH. Our findings demonstrate that GABARAPL1 acts as a tumor promoter in TNBC partly through MTDH. Targeting at GABARAPL1 could be a potential therapeutic strategy for TNBC.

Plausible genome-wide associations for episodic neurological diseases (such as migraine, epilepsy and ataxias) have been slow to emerge. The first such association was reported in a recent genome-wide association study of migraine, with quantitative expression analysis linking the variant to a nearby regulatory gene, MTDH/AEG-1. This putative mechanism, regulating the expression of the primary glutamate transporter in the brain, EAAT2/GLT-1, has interesting implications bridging the gap between Mendelian and common forms in this key group of disorders.

We have reported Metadherin (MTDH) was proven to be overexpression and involved in malignance of chronic lymphocytic leukemia (CLL) via Wnt signaling pathway. In this study, we further investigate the role of MTDH in regulation of BCR signaling pathway in CLL. Six CLL samples whose cells were proliferation after BCR activation were chosen from patients with unmutated IgVH. CCK-8 method used to evaluate the proliferation rate. MTDH expression was measured by quantitative PCR and Western blot. After BCR activation, there exist upregulation of MTDH expression in mRNA and protein level in all six CLL patients (P<0.05). In cell line MEC-1, we observed the same pro-proliferation effect accompanying with elevated MTDH expression. The proliferation effects of BCR activation to MEC-1 can be inhibited by MTDH interference. The results of this study indicate that MTDH involved in the pro-proliferation effect of BCR activation in CLL. And the results imply that MTDH can be a potential therapy target of CLL.

BACKGROUND

The etiopathogenesis of prostate cancer (PC) is still not clear, but hormonal, genetic, and environmental factors are thought to play a role in the tumor pathogenesis. Astrocyte elevated gene-1(AEG-1) as a novel transmembrane protein is predominantly located in the perinuclear region and endoplasmic reticulum. It has been found that AEG-1 upregulation increases the invasive ability of glioma and prostate cancer. Basic fibroblast growth factor (bFGF), matrix metalloproteinase-9 (MMP-9), cyclooxygenases-2 (COX-2), and adenomatous polyposis coli (APC) are very important in tumor progression as well.

METHODS

This study included 97 radical prostatectomy specimens. IHC stains for bFGF, MMP-9, COX-2, APC, and AEG-1 were performed on the tissue microarray using standard procedures. For each patient, the age, Gleason score, tumor volume, lymphovascular invasion, lymph node metastasis, surgical margin, and the invasion of vesiculoseminalis areas were assessed. Analyses were performed using the statistical PASW (ver. 18).

RESULTS

Statistically significant positive relationships were found MMP-9 and COX-2 (r = 0.242 and P = 0.017), between MMP-9 and APC (r = 0.207 and P = 0.043), and between bFGF and AEG-1 (r = 0.295 and P = 0.004). However, the relationships between age and staining results and tumor volume and staining results were not found to be significant. Although a positive correlation was found between the Gleason score and tumor volume and the Gleason score and age (r = 0.415 and P = 0.0001; r = 0.246 and P = 0.015, respectively), we did not find a statistically significant relationship between other stains and other prognostic parameters (lymphovascular invasion, lymph node metastasis, surgical margin, or vesiculoseminalis invasion).

CONCLUSIONS

The relationships we found between MMP-9 and COX-2, between MMP-9, and APC and between bFGF and AEG-1 as independent prognostic parameters could be helpful in the development of new therapeutic procedures.

The ascomycete Cladosporium herbarum is a prominent fungal inducer of Type I allergy. The only major allergen identified so far is Cla h 8, a NADP-dependent mannitol dehydrogenase (MtDH). MtDH, a cytoplasmic protein of 28.5kDa, belongs to the Short chain Dehydrogenases/Reductases (SDR), acting as a NADP-dependent oxidoreductase. In this study, we found that C. herbarum MtDH can exist as monomers, dimers and tetramers in solution and, correspondingly, forms tetramers and higher oligomers in two crystal structures. Additionally, we identified a unique adaptive binding site for the metal ions Na(+) and Zn(2+) that were distinguished by an anomalous dispersion experiment. A Translation-Libration-Screw analysis confirmed the stabilising effect of Zn(2+) for the tetrameric assembly. Moreover, the zinc containing structure explains the mode of MtDH multimerisation by metal bridging of the tetramers. The formation of oligomers and higher multimers of MtDH provides a missing link to its allergenic properties. Based on the well defined active site region and a comparative analysis with related structures, we can also clarify the atypical enzymatic properties of MtDH by two alternative binding modes of the substrate to the active site.

Tumorigenesis is a complex and poorly understood process in which oncogenes can activate competing proapoptotic and proneoplastic programs. A recent paper in Cancer Cell demonstrates a dual role of the MTDH-SND1 complex in suppressing the apoptotic response and promoting breast cancer development, suggesting a new therapeutic avenue.

BACKGROUND

Columnar cell lesions (CCLs) are possible precursors of breast cancer, but little is known about the role of breast cancer-related genes in the progression of CCL to invasive breast cancer.

METHODS

Gene copy numbers of 17 breast cancer-related genes were analyzed using Multiplex Ligation-dependent Probe Amplification (MLPA) in CCL (N = 28), ductal carcinoma in situ (DCIS) grade I likely originating from CCL (N = 5), and paired CCL (N = 14/28) with DCIS (N = 7) and/or invasive carcinoma (N = 13). The genes included were BIRC5, C11orf30, CCND1, CCNE1, CDH1, CPD, EGFR, ERBB2, ESR1, FGFR1, IKBKB, MAPT, MED1, MTDH, MYC, TOP2A and TRAF4.

RESULTS

No high level gene amplifications were observed in CCL, but copy number gains were encountered for the C11orf30 (3/28), MYC, CPD, MTDH (2/28), and CCND1, CCNE1, ESR1 and TOP2A genes (1/28). In addition, CDH1 showed loss in 2/28 and TOP2A in 1/28 cases. CCLs with or without atypia exhibited comparable numbers of copy number changes (p = 0.312). Overall, the frequency of gene copy number changes increased from CCL towards DCIS and invasive carcinoma (p = 0.004). Also in the cases with synchronous lesions, the CCLs exhibited fewer copy number changes than the DCIS/invasive carcinomas.

CONCLUSIONS

CCLs carry copy number changes of several known breast cancer-related genes, thereby substantiating their role in breast carcinogenesis. Among them, CCND1 and ESR1 copy number gains and CDH1 copy number losses are of particular interest. Since the copy number changes observed were more prevalent in DCIS and invasive carcinoma than in CCL, the corresponding gene alterations may represent rather late occurring events in low nuclear grade breast carcinogenesis.

OBJECTIVE

To determine the expression levels of EphA7 and MTDH and detect their clinicopathological significance in the peritumoral normal tissues and the squamous cell cancer of the tongue.

METHODS

Envision immunohistochemistry was used to assay the expression levels of EphA7 and MTDH in the conventional paraffin-embedded sections from specimens of squamous cell cancer (n=45) and peritumoral normal tissues (n=10).

RESULTS

The positIVe rates of EphA7 and MTDH were significantly higher in the squamous cell cancer than those in the peritumoral normal tissues ( χ(2)(EphA7)=4.14; χ(2)(MTDH)= 5.25; P < 0.05). The positIVe rates of EphA7 and MTDH expression were significantly lower in the cases of histological grade I-II,clinical stage I-II, and no-metastasis of neck lymph node than those in the histological grade III-IV, clinical stage III-IV, and metastasis of neck lymph node (P <0.05 or P <0.01).

CONCLUSIONS

The expression levels of EphA7 and/or MTDH might have important effect on the carcinogenesis and progression of tongue cancer. Overexpression of EphA7 and/or MTDH might have poor prognosis.

The mannitol-2-dehydrogenase (MtDH) from Gibberella zeae was purified and the corresponding cDNA identified. Purification of MtDH was accomplished using a combination of ammonium sulfate fractionation, anion exchange and dye-ligand chromatography. Final purification was achieved following electroelution from a native gel. Molecular mass determination based on SDS-PAGE indicated that the denatured protein was 29 kDa. Native protein mass was determined to be 110 kDa using gel permeation chromatography, indicating a tetrameric form. The pH optima for mannitol oxidation and fructose reductase activities were 9.0, and 7.0, respectively. Activity with sorbitol as the substrate was 21% of activity with mannitol. Kinetic parameters were determined by direct-linear plots of enzyme activity vs. substrate concentrations. Fructose concentrations above 600 mM and NADPH concentrations above 0.3 mM caused substrate inhibition. Comparisons of predicted amino acid sequences of several fungal MtDHs indicated high conservation within the phyla. A possible role for MtDH in generation of turgor pressure for forcible ascospore discharge is discussed.

The aim of this study was to clarify the importance of microRNA‑375 (miR‑375) expression in patients with esophageal squamous cell carcinoma (ESCC) and to examine the in vivo antitumor effects of miR‑375 in a model of ESCC using a non‑viral delivery system. We estimated the miR‑375 and LDHB and AEG‑1/MTDH mRNA expression of the ESCC tumors from 85 patients. The correlation between the miR‑375 expression and clinicopathological features, including the prognosis, were evaluated. The presence of high miR‑375 expression was associated with lymphatic vessel invasion, while a low expression of miR‑375 significantly correlated with a poor prognosis for the 85 ESCC patients. We also found that there was a significant inverse correlation between the expression of miR‑375 and that of LDHB. Before the examination of miR‑375 in the in vivo assay, we confirmed that atelocollagen prolonged the accumulation of miRNA by using fluorescently‑labeled miRNA and an in vivo imaging system. We injected the miR‑375/atelocollagen complex or a control‑miRNA/atelocollagen complex into mice bearing TE2 and T.Tn xenografts via subcutaneous (s.c.) injections. The growth of both the TE2 and T.Tn tumors in the miR‑375 groups was significantly suppressed compared with that in the control‑miRNA groups. In addition, The LDHB mRNA expression of TE2 xenografts was significantly downregulated after miR‑375 treatment. In conclusion, it might be possible for the level of miR‑375 expression to be a utilized as a prognostic indicator for ESCC patients. The administration of miR‑375 using a non‑viral delivery might represent a powerful new treatment for ESCC.

Angiogenesis plays an important role in cancer growth, invasion and metastasis. It has been confirmed that metadherin (MTDH) is associated with angiogenesis. However, the detailed mechanism of MTDH on angiogenesis has not yet been reported. In this study, we demonstrate the anti-angiogenic function of MTDH in breast cancer. With RNA interference strategies, we found that knockdown of MTDH inhibits cellular angiogenesis both in vitro and ex vivo. Furthermore, we revealed that ERK1/2 pathway is involved in the anti-angiogenic function of MTDH, and the function can be partially reversed via upregulation of microRNA-21 (miR-21). In conclusion, knockdown of MTDH can inhibit angiogenesis in breast cancer. These results show that MTDH is a viable therapeutic target for anti-angiogenesis in breast cancer.

Recent studies have reported an important role for microRNA-1271 (miR-1271) in tumorigenesis. However, the role of miR-1271 in colorectal cancer remains unknown. Here, we found that miR-1271 was significantly decreased in colorectal cancer tissues and cell lines. Overexpression of miR-1271 inhibited cell proliferation, colony formation, cell invasion, and induced cell cycle arrest in colorectal cancer cells. Metadherin (MTDH) was identified as a target gene of miR-1271. Moreover, miR-1271 negatively regulated MTDH expression in colorectal cancer cells and reversely correlated with MTDH expression in colorectal cancer specimens. Additionally, miR-1271 also regulated the activation of Wnt signaling in colorectal cancer cells. The restoration of MTDH expression significantly reversed the antitumor effect of miR-1271 in colorectal cancer cells. These findings indicate an important role for miR-1271/MTDH in the tumorigenesis of colorectal cancer, and suggest that miR-1271 may be a novel therapeutic target for colorectal cancer.

In this study, we isolated and purified one homogeneous polysaccharide (TRP) from the fruiting bodies of Trametes robiniophila Murrill, and its average molecular weight was estimated to be 8.7 × 10(4) Da. Monosaccharide composition analysis by gas chromatography (GC) indicated that TRP was composed of glucose, galactose, and arabinose in the molar ratio of 4.2:1.10:1.06. Particularly, we evaluated the anti-cancer efficacy of TRP on human osteosarcoma U-2 OS cells in vitro and associated possible molecular mechanism. Our result provided the first evidence that treatment of U-2 OS cells with TRP resulted in a dose- and time-dependent inhibitory effect on cell proliferation of U-2 OS cells and caused apoptotic death. Moreover, TRP induced the apoptosis of U-2 OS cells via a mitochondria-dependent pathway, as evidenced by an increase in Bax/Bcl-2 ratio, a loss of mitochondrial membrane potential (Δψm), release of cytochrome c from the mitochondria to the cytosol, activation of caspase-9 and caspase-3, and cleavage of poly(ADP-ribose) polymerase (PARP) in U-2 OS cells. In addition, overexpression of metadherin (MTDH), one carcinogene, was inhibited in U-2 OS cells after exposure to TRP for 24 h. Our findings suggested that TRP inhibited the proliferation of human osteosarcoma cancer cells by promoting apoptosis through the intrinsic mitochondrial pathway, as well as inhibition of MTDH expression.

Metadherin (MTDH) is highly expressed in many tumors and is involved in the proliferation, metastasis and drug resistance of tumor cells by regulating multiple signaling pathways. Our previous studies demonstrated that MTDH is overexpressed in diffuse large B cell lymphoma (DLBCL) and involved in apoptosis resistance, in part, via Wnt signaling. Here, we investigated the role of MTDH in the chemo-sensitivity of DLBCL. The study was performed in the DLBCL cell line LY8 to investigate the relationship between MTDH expression and doxorubicin (DOX) sensitivity in DLBCL. A MTDH interference model was developed in LY8 cells by transfected with lentivirus which is carrying MTDH interference sequence. Western blot was used to detect the protein expression. A CCK-8 assay was used to evaluate cell proliferation. The results showed that DOX treatment had no effect on the intracellular MTDH expression of LY8 cells. The proliferation of LY8 cells was inhibited after MTDH interference. MTDH interference increased the DOX sensitivity in the LY8 cell lines. The results suggested that MTDH is a potential therapeutic target in DLBCL, and it cooperates with DOX in treatment of DLBCL.