Studies have rarely been conducted on the role of miRNAs in prostate cancer (PCa) cell progression by directly targeting MTDH, at least to the best of our knowledge. Thus, the present study aimed to identify miRNAs closely related with metadherin (MTDH) and to determine their roles in PCa. For this purpose, the expression levels of MTDH in PCa tissues and cell lines were examined by RT‑qPCR, immunohistochemistry and western blot analysis. By cell transfection, MTDH was either overexpressed in the normal prostate epithelial cell lines or silenced in tumor cell lines to determine cell viability, invasion and migration. Bioinformatics analysis, RT‑qPCR, western blot analysis, dual‑luciferase reporter assay and MTT assay were performed to identify direct the target of MTDH and to examine tumor cell viability. Rescue experiments using the PC‑3 and LNCaP cells were carried out by MTT assay, scratch wound assay, Transwell assay, RT‑qPCR and western blot analysis. Experiments were also conducted using 46 PCa human cancer and adjacent tissues, as wells as on 501 cases of PCa from the TCGA database. It was confirmed that the overexpression of MTDH was associated with a poor prognosis of patients. The overexpression of MTDH was found to promote the viability, invasion and migration of PCa cells. miR‑145‑5p and miR‑145‑3p identified from 16 miRNAs were found to be closely related to PCa and to be the targets of MTDH. Both these miRNAs were found to significantly suppress the growth and metastasis of PCa cells by negatively regulating the expression of MTDH. On the whole, the findings of this study demonstrate that MTDH functions as an oncogene in PCa and the inhibition of MTDH by miR‑145‑5p or miR‑145‑3p suppressed the growth and metastasis of PCa cells. The miR‑145‑5p/MTDH and miR‑145‑3p/MTDH pathways may thus become novel treatment targets for PCa.

BACKGROUND Reports show that ultrasound-targeted microbubble destruction (UTMD) is a promising method of gene therapy, and metadherin (MTDH) is related to the development of breast cancer. Thus, we investigated the role of MTDH in breast cancer and compared the effect of suppressing MTDH by shRNA using liposome, UTMD, or the combination of these 2 methods. MATERIAL AND METHODS Graphing of survival curves of MTDH was analyzed by bioinformatics. UTMD was conducted using an ultrasonic therapeutic apparatus. Cell counting kit-8 (CCK-8) assay was used to measure cell viability. Migration and invasion rates were measured by wound healing test and Transwell invasion assay, respectively. The expression of MTDH, E-cadherin, metastasis-associated protein-1 (MTA-1), matrix metalloproteinase (MMP)-2, and MMP-9 were measured by Western blot and qPCR. RESULTS The prognosis of breast cancer can be decreased by the high expression of MTDH, and elevated expression of MTDH was discovered in MCF-7, MCF-10A, and T47D cell lines. UTMD combined with liposome is most efficient in transfecting shRNA, clearly suppressing the expression of MTDH and thereby decreasing cell viability, migration, invasion rate, and epithelial- mesenchymal transition (EMT) processes in the MCF-7 cell line. CONCLUSIONS UTMD combined with liposome could be used as a more efficient way to transfect shRNA into cells to suppress the expression of MTDH and thus lead to the downregulation of proliferation, migration, and EMT processes of the MCF-7 cell line, showing the potential for use in gene therapy.

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.

BACKGROUND: Metadherin (MTDH) is an oncogene that has been overexpressed in numerous types of malignancies including colorectal cancer (CRC). However, few investigations associated with the biological behavior of MTDH in CRC have been performed. The aim of the present study was to investigate the effect of modification of MTDH gene expression (knockdown and overexpression) on the biological behavior of CRC in vitro.
METHODS: MTDH gene expression was analyzed in two CRC cell lines (Caco-2 and HCT116) by qPCR. MTDH was down-regulated via siRNA-mediated knockdown of human MTDH in HCT116 cells, which express high endogenous levels of MTDH gene. Also, MTDH gene was up-regulated via transfection of Caco-2 cells, which express low endogenous levels of MTDH gene, with a plasmid carrying human MTDH gene.
RESULTS: Knockdown of MTDH gene expression significantly decreased the gene expression of multidrug resistance gene (MDR1), Snail and NF-κB p65, but increased the gene expression of E-cadherin. Furthermore, MTDH-knockdown significantly decreased anaerobic glycolysis (glucose consumption and lactate production), cell proliferation ability and transformation into cancer stem cell. Moreover, up-regulation of MTDH gene significantly increased the gene expression of MDR1, Snail and NF-κB p65, deceased the gene expression of E-cadherin, enhanced cell proliferation, and anaerobic glycolysis and activated transformation into cancer stem cells.
CONCLUSIONS: MTDH has an important role in promoting CRC aggravation. Also, inhibition of MTDH expression may attenuate the carcinogenic behavior of CRC cells. Furthermore, MTDH-associated NF-κB p65 signaling pathways may be involved in mediating the biological behavior of CRC.

Epithelial-mesenchymal transition (EMT) leads to tumor dissemination and metastasis. Metadherin (MTDH) is an oncogene that plays an important role in metastasis regulation. This study tries to investigate the effect of MTDH gene up-regulation on the activation of EMT in colorectal cancer (CRC) cells and identify the role of NF-κB p65. The CaCO2 cells were divided into three groups: one control group of cultured CaCO2 cells (C1), and two groups of CaCO2 cells co-transfected using human MTDH expression plasmid with either siRNA targeting human NF-κB p65 or its negative control (C2 and C3 respectively). The gene modification was confirmed by qPCR and the effect of gene modification on CRC aggravation was studied. MTDH up-regulation significantly promoted CRC cell proliferation, activated anaerobic respiration (glucose consumption and lactate production), and increased gene expression of multidrug resistance gene (MDR1), Snail transcription factor and NF-κB p65, but decreased the gene expression of E-cadherin. Moreover, MTDH up-regulation led to a significant increase in the acquisition of surface markers of CRC stem cells. Interference with NF-κB p65 gene expression reversed the action of MTDH gene up-regulation on MDR1 and E-cadherin gene expression and anaerobic respiration. Moreover, NF-κB p65 interference significantly decreased MTDH-induced cell proliferation and acquisition of surface markers of CRC stem cells but didn't affect the Snail transcription factor. MTDH-dependent EMT in CRC is activated via NF-κB p65 and is mediated by up-regulation of Snail. These results identify a pathway by which MTDH regulates NF-κB p65 induced EMT during CRC cell metastasis.

The dysregulation of microRNAs (miRNAs/miRs) has become increasingly recognized as a primary feature of retinoblastoma (RB). Furthermore, miRNAs have been demonstrated to be involved in the occurrence and development of RB. Therefore, it is crucial to investigate the expression profile and roles of miRNAs in RB in order to identify potential therapeutic targets to treat patients with RB. The expression profile and biological roles of miRNA‑504 (miR‑504) have been reported in numerous types of human cancer; however, the roles of miR‑504 in RB remain unknown. In the present study, it was demonstrated that miR‑504 expression was significantly decreased in RB tissues and cell lines. Functional analysis identified that resumption of miR‑504 expression suppressed cell proliferation and invasion in RB. Furthermore, astrocyte elevated gene‑1 (AEG‑1) was determined to be a direct target of miR‑504 in RB, and a negative correlation between miR‑504 and AEG‑1 mRNA expression levels was observed in RB tissues. Additionally, the tumor‑suppressing effects of miR‑504 overexpression in RB cells could be rescued by AEG‑1 upregulation. In conclusion, these results indicated a significant role of the miR‑504/AEG‑1 pathway in inhibiting the aggressiveness of RB, suggesting that this miRNA may be employed as a therapeutic target for the treatment of patients with this disease.

PURPOSE: To investigate the effect of astrocyte elevated gene-1 (AEG-1) overexpression on the biological behaviour of human retinoblastoma (RB) cells and its possible mechanism.
METHODS: Three human RB cell lines (SO-RB50, Y79 and WERI-RB1) were infected with AEG-1-GFP recombinant lentiviral vectors to induce AEG-1 overexpression, while the cells infected with negative lentiviral vectors and cells without any intervention formed control groups.
RESULTS: All three RB cell lines showed an overexpression of AEG-1 after lentivirus infection (p < 0.001 for all three cell lines). The survival rate of RB cells increased (all p < 0.001) in the AEG-1 overexpressed groups when compared with the control groups. There was a decrease in G0/G1 cell cycle phase arrest and an accumulation in G2/M cell cycle phase in all three RB cell lines (p < 0.001), with an induction in the S phase in WERI-RB1 cells. It was paralleled by a downregulation of p21 and p27 proteins and an upregulation of the Cdc2 protein. The apoptosis rate of RB cells declined (p < 0.001) when AEG-1 was overexpressed, in association with an upregulation of Bcl-2 protein and a downregulation of Bax protein and cleaved caspase-3 proteins.
CONCLUSIONS: A lentivirus-mediated AEG-1 overexpression in RB cells led in vitro to a growth promotion and an apoptosis inhibition of human RB cells, associated with an upregulation of the Bcl-2 protein, a downregulation of the Bax protein and of cleaved caspase-3 proteins, and with alterations of the cell cycle. AEG-1 may be involved in the development and progression of RB.

Numerous microRNAs (miRNAs) are dysregulated in tongue squamous cell carcinoma (TSCC), and their dysregulation has been demonstrated to have a strong correlation with TSCC progression via regulation of their targets. Therefore, miRNAs have potential use in the diagnosis and treatment of patients with TSCC. In the present study, miRNA‑758 (miR‑758) expression in TSCC tissues and cell lines was detected through reverse transcription‑quantitative polymerase chain reaction, and the effects of miR‑758 on TSCC cell proliferation and invasion were investigated by using Cell Counting kit‑8 and Transwell invasion assays. A luciferase reporter assay was performed to determine the target interaction between miR‑758 and metadherin (MTDH) in TSCC cells. The results revealed that miR‑758 was downregulated in TSCC tissues and cell lines. miR‑758 overexpression restricted the proliferation and invasion of TSCC cells. Additionally, MTDH was verified as a direct target gene of miR‑758 in TSCC cells. Furthermore, MTDH was observed to be upregulated in TSCC tissues, and the upregulation of MTDH was inversely correlated with miR‑758 expression. Moreover, restored MTDH expression significantly counteracted the suppressive effects of miR‑758 overexpression on TSCC cells. These results suggested that miR‑758 may prevent TSCC progression and development by directly targeting MTDH, thereby providing evidence that miR‑758 is a novel therapeutic target for the treatment of patients with TSCC.

Gastric cancer (GC) is one of the most common and fatal types of cancers worldwide and the specific mechanism has not been completely elucidated. microRNA (miR)‑3664‑5P has rarely been studied and the aim of the present study was to assess an association between miR‑3664‑5P and GC. Differences in miR‑3664‑5P expression in 100 GC (0.1846±0.08276) and paired normal tissues (0.4382±0.1595) were detected using reverse transcription‑quantitative polymerase chain reaction assays (P<0.001). 5‑Ethynyl‑2‑deoxyuridine, Cell Counting Kit‑8, transwell and flow cytometry assays were performed in vitro and the results were further verified using a mouse xenotransplantation and a lung metastasis model in vivo. miR‑3664‑5P was significantly downregulated in GC tissues when compared with normal tissues and positively associated with the prognosis of patients with GC (P<0.001). Overexpression of miR‑3664‑5P suppressed and miR‑3664‑5P knockdown promoted the proliferation and metastasis of GC cells in vitro and in vivo. Following the application of bioinformatic algorithms and luciferase reporter assays, metadherin (MTDH) was confirmed as the target gene of miR‑3664‑5P. miR‑3664‑5P reduced MTDH expression and downregulated the nuclear factor (NF)‑κB signaling pathway. Rescue experiments demonstrated that suppression of MTDH restored the effect of miR‑3664‑5P inhibitors on GC cell lines. The results suggested that miR‑3664‑5P suppressed the proliferation and metastasis of GC cells by attenuating the NF‑κB signaling pathway via MTDH targeting. Consequently, miR‑3664‑5P may have potential to be an independent prognostic factor and biomarker in GC.

OBJECTIVE: MicroRNA-384 (miR-384) has been reported to function as a tumor suppressor in multiple cancers; however, its role in gastric cancer (GC) remains unclear.
METHODS: We measured expression levels of miR-384 in GC cell lines and in a normal gastric cell line (GES-1). The association between miR-384 and the metadherin gene ( MTDH) was assessed by luciferase reporter assay and western blot. The effects of the miR-384/MTDH axis on GC cell behaviors were measured by CCK-8, wound-healing, and transwell invasion assays.
RESULTS: miR-384 was significantly downregulated in GC cell lines compared with normal gastric cells. MTDH was identified as a direct target of miR-384 by bioinformatics analysis, luciferase assay, and western blot. Functional assays demonstrated that miR-384 inhibited GC cell proliferation, migration, and invasion through targeting MTDH.
CONCLUSION: These results reveal that miR-384 acts as a tumor suppressor in GC and suggest that the miR-384/MTDH axis may be a potential therapeutic target for GC.

Numerous microRNAs (miRNAs) have been demonstrated to be downregulated or upregulated in hepatocellular carcinoma (HCC) and play important roles in its occurrence and development. Therefore, the investigation of miRNAs and their functions implicated in the genesis and development of HCC may provide key clues for the identification of effective therapeutic approaches for patients with this disease. The aims of the present study were to detect miRNA‑466 (miR‑466) expression in HCC tissues and cell lines and to determine its effects on HCC cell proliferation, apoptosis and metastasis, as well as to explore the mechanisms underlying the tumor‑suppressing roles of miR‑466 in HCC. In the present study, reverse transcription‑quantitative polymerase chain reaction (RT‑qPCR) was performed to detect miR‑466 expression in HCC tissues and cell lines. The effects of miR‑466 upregulation on HCC cell proliferation, apoptosis, migration and invasion were determined using Cell Counting Kit‑8 assay, flow cytometry analysis and Transwell chamber assay, respectively. The potential target gene of miR‑466 was predicted using bioinformatic analysis, which was further confirmed by luciferase reporter assay, RT‑qPCR and western blot analysis. It was found that miR‑466 was obviously decreased in HCC tissues and cell lines. The results of functional experiments revealed that restoration of miR‑466 expression suppressed the proliferation, induced apoptosis, and reduced the metastasis of HCC cells. In addition, metadherin (MTDH) was identified as a direct target of miR‑466 in HCC cells. Furthermore, MTDH was upregulated in HCC tissues, which was inversely correlated with the miR‑466 level. Moreover, inhibition of MTDH displayed similar tumor‑suppressing roles as miR‑466 upregulation in HCC cells. In addition, MTDH reintroduction restored the tumor‑suppressor activity of miR‑466 overexpression in HCC cells. These findings suggest that miR‑466 is a potential therapeutic tool for HCC therapy.

Laryngeal carcinoma is one of the most common tumors concerning otorhinolaryngology head and neck surgery, however, the pathogenesis of laryngeal carcinoma remains unclear. MicroRNAs (miRNAs) have been reported to play vital roles in the pathogenesis of laryngeal carcinoma Herein, the present study was designed to explore the function and mechanism of miRNA‑98 in hypopharyngeal carcinoma. In brief, qRT‑PCR, MTT assay, western blot analysis, Transwell assay and luciferase reporter assay were performed. Based on the results, miRNA‑98 expression was downregulated in patients with hypopharyngeal carcinoma. Downregulation of miRNA‑98 promoted cell growth and migration, and decreased the apoptotic rate of hypopharyngeal carcinoma cells. Overexpression of miRNA‑98 increased the apoptotic rate, and inhibited cell growth and migration of hypopharyngeal carcinoma cells. Moreover, luciferase reporter assays revealed that MTDH is a direct target of miRNA‑98 and overexpression of miRNA‑98 induced the protein expression of PTEN and suppressed that of PI3K and p‑Akt. si‑MTDH attenuated the anticancer effects of miRNA‑98 on hypopharyngeal carcinoma via the PTEN/AKT pathway. To the best of our knowledge, the present study confirmed for the first time that miRNA‑98 inhibits hypopharyngeal carcinoma cell proliferation and induces apoptosis via the PTEN/AKT pathway by MTDH.

Objective: Lobaplatin shows antitumor activity against a wide range of tumors, including metastatic breast cancer (BCa). The overexpression of metadherin (MTDH) is associated with poor prognosis of BCa patients. This study was designed to investigate the effect of lobaplatin on MCF-7 cell proliferation and its association with MTDH expression.
Patients and methods: Clinical treatment for BCa using lobaplatin, in combination with other general chemotherapy drugs, was administered to 32 BCa patients. The safety, effectiveness, and prognosis in lobaplatin-treated BCa patients were compared with those in controls (n=32). In vitro experiments were performed in MCF-7 cells to investigate the effect of lobaplatin on cell proliferation, apoptosis, and MTDH expression.
Results: We found the intraoperative local chemotherapy using lobaplatin was safe and effective for BCa treatment, in comparison with the patients administered general chemotherapy drugs. Treatment of MCF-7 cell cultures with lobaplatin significantly reduced cell proliferation and increased cell apoptotic percentage. The expression of MTDH and Bcl-2 was inhibited by lobaplatin and that of Bax was increased by lobaplatin. Moreover, we observed the inhibition of MTDH by shRNA reduced cell proliferation and enhanced cell apoptosis.
Conclusion: Lobaplatin was a safe and effective adjuvant chemotherapy for BCa. The effect of lobaplatin on inhibiting MCF-7 cell proliferation and inducing cell apoptosis might be, as least in part, mediated by suppressing the expression of oncogene MTDH.

BACKGROUND Clear cell renal cell carcinoma (ccRCC) is usually incurable once it progresses to metastatic stage. Hence, in-depth investigations to reveal the precise molecular mechanisms behind the metastasis of ccRCC are required to improve the therapeutic outcome of ccRCC. MATERIAL AND METHODS The level of astrocyte elevated gene 1 (AEG-1) in ccRCC tissues and cell lines was determined by quantitative real-time PCR (qRT-PCR) assay. The MTS, colony formation, wound-healing, and Transwell invasion assays were used to assess the role of AEG-1 in ccRCC cells growth, migration, and invasion in vitro, respectively. Xenograft model and lung metastasis models were constructed to analyze the functions of AEG-1 in ccRCC cells growth and metastasis in vivo. RESULTS We found that AEG-1 was overexpressed in ccRCC and was associated with the progression of ccRCC. Knocked-down AEG-1 impaired the migration and invasion of ccRCC cells in vitro. Furthermore, under-expression of AEG-1 caused complete inhibition of ccRCC cells growth and metastasis in vivo. In contrast, overexpression of AEG-1 significantly increased the migration and invasion ability of ccRCC cells in vitro. Finally, we revealed that AEG-1 boosted the metastatic ability of ccRCC cells via regulating Notch homolog 1 (Notch1). CONCLUSIONS The AEG-1/Notch1 signaling axis plays a vital role in ccRCC cell growth and metastasis.

To investigate the role of Astrocyte elevated gene-1 (AEG-1) in the development and progress of pancreatic cancer, short hairpin RNA (shRNA) was inserted into the RNA interference vector to knock-down the endogenous AEG-1 in two pancreatic cancer cell lines: AsPC-1 and PANC-1. Our results showed that silencing of AEG-1 suppressed the proliferation, colony formation ability, and cell stemness of AsPC-1 and PANC-1 cells, and inhibited their G1-to-S phase transition. Results from apoptosis assay showed that knock-down of AEG-1 led to cell apoptosis. The expression of anti-apoptotic Bcl-2 was downregulated and that of the pro-apoptotic Bax and cleaved caspase-3 was upregulated in AEG-1-silenced pancreatic cancer cells. Further, the capability of AEG-1-silenced cells to migrate and to invade through the Matrigel-coated membrane was weaker, and the expression of matrix metallopeptidase 2 (MMP-2) and MMP-9 were decreased. Moreover, the AKT-β-catenin signaling pathway was inhibited in the cells with knock-down of AEG-1. In addition, the growth of xenograft tumors formed by AsPC-1 and PANC-1 cells was suppressed by AEG-1 shRNA. In conclusion, our study demonstrates that pancreatic cancer cells require AEG-1 to maintain their survival and metastasis, suggesting AEG-1 as a potential target for the treatment of pancreatic cancers.

BACKGROUND: Drug resistance of paclitaxel (TAX), the first-line chemotherapy drug for breast cancer, was reported to develop in 90% of patients with breast cancer, especially metastatic breast cancer. Investigating the mechanism of TAX resistance of breast cancer cells and developing the strategy improving its therapeutic efficiency are crucial to breast cancer cure.
METHODS AND RESULTS: We here report an elegant nanoparticle (NP)-based technique that realizes efficient breast cancer treatment of TAX. Using lentiviral vector-mediated gene knockdown, we first demonstrated that TAX therapeutic efficiency was closely correlated with metadherin (MTDH) gene expression in breast cancer cell lines. This finding was also supported by efficacy of TAX treatment in breast cancer patients from our clinical studies. Specifically, TAX treatment became more effective when MTDH expression was decreased in MCF-7 cancer cells by the blocking nuclear factor-kappa B (NF-κB) pathway. Based on these findings, we subsequently synthesized a polymeric NP that could co-deliver MTDH-small interfering RNA (MTDH-siRNA) and TAX into the breast cancer tumors in tumor-bearing mice. The NPs were composed of a cationic copolymer, which wrapped TAX in the inside and adsorbed the negatively charged siRNA on their surface with high drug-loading efficiency and good stability.
CONCLUSIONS: NP-based co-delivery approach can effectively knock down the MTDH gene both in vitro and in vivo, which dramatically inhibits breast tumor growth, achieving effective TAX chemotherapy treatment without overt side effects. This study provides a potential therapeutic strategy for the treatment of a wide range of solid tumors highly expressing MTDH.

Ovarian cancer has a high mortality rate among women worldwide. Radiotherapy is considered an effective method of ovarian cancer treatment, however, radioresistance presents a challenge. It is necessary to develop techniques that can increase radiosensitivity in ovarian cancer, and gene therapy is a promising option. The aim of the present study was to investigate the effects of metadherin (MTDH) silencing on the radiosensitivity of ovarian cancer. Ovarian cancer tissues (n=273) and normal ovarian tissues (n=277) were used, as were SKOV3 ovarian cancer cells and the immortalized human ovarian epidermal HOSEpiC cell line. MTT, Transwell and wound-healing assays were performed to assess the proliferation, invasion and migration abilities of the SKOV3 cells. Colony-forming assays and flow cytometry were applied to detect the radiosensitivity and apoptosis of the SKOV3 cells. Nude mouse xenograft models were established to evaluate the effect of MTDH gene silencing on tumor growth and the efficacy of radiotherapy. Ovarian cancer, in tissues and cells, was demonstrated to have a high level of MTDH. Additionally, MTDH silencing was found to significantly inhibit proliferation, migration and invasion, and induce apoptosis in SKOV3 cells, and it was suggested that MTDH depletion significantly increased the sensitivity of the SKOV3 cells to X-ray radiation. MTDH silencing enhanced radiosensitivity and delayed tumor growth in the nude mouse xenograft model. Collectively, the results obtained in the present study suggest the potential role of MTDH silencing as a technique for ameliorating radioresistance in ovarian cancer. The present study provides a promising experimental basis for the improvement of ovarian cancer radiotherapy treatment.

BACKGROUND: This study was to examine the link between astrocyte elevated gene-1 (AEG-1) and hypoxia induced-chemoresistance in T-cell non-Hodgkin's lymphoma (T-NHL), as well as the underlying molecular mechanisms.
METHODS: Expression of AEG-1, LC3-II, and Beclin-1 were initially examined in human T-NHL tissues (n = 30) and normal lymph node tissues (n = 16) using western blot, real-time PCR and immunohistochemistry. Western blot was also performed to analyze the expression of AEG-1, LC3-II, and Beclin-1 in T-NHL cells (Hut-78 and Jurkat cells) under normoxia and hypoxia. Additionally, the proliferation and apoptosis of Hut-78 cells exposed to different concentration of Adriamycin (ADM) in normoxia and hypoxia were evaluated by MTT and Annexin-V FITC/PI staining assay. Finally, the effects of AEG-1 on Hut-78 cells exposed to ADM in hypoxia were assessed by MTT and Annexin-V FITC/PI staining assay, and 3-MA (autophagy inhibitor) was further used to determine the underlying mechanism.
RESULTS: AEG-1, LC3-II and Beclin-1 expression were significantly increased in T-NHL tissues compared with normal tissues. Incubation of Hut-78 and Jurkat cells in hypoxia obviously increased AEG-1, LC3-II and Beclin-1 expression. Hypoxia induced proliferation and reduced apoptosis of Hut-78 cells exposed to ADM. AEG-1 overexpression further increased proliferation and decreased apoptosis of Hut-78 cells exposed to ADM in hypoxia. Moreover, overexpression of AEG-1 significantly inversed 3-MA induced-changes in cell proliferation and apoptosis of Hut-78 cells exposed to ADM in hypoxia.
CONCLUSIONS: This study suggested that AEG-1 is associated with hypoxia-induced T-NHL chemoresistance via regulating autophagy, uncovering a novel target against hypoxia-induced T-NHL chemoresistance.

Multiple myeloma (MM) is a hematological tumor and is characterized by the infiltration of malignant clonal plasma cells (PCs) in bone marrow. MicroRNAs (miRNAs or miRs) have been reported to play an important role in the genesis and progression of MM. However, little is known about the clinical diagnostic value and biological functions of miR-30d in MM. In this study, to investigate the role of miR-30d in MM, we used reverse transcription-quantitative polymerase chain reaction quantitative (RT-qPCR) to detect the relative expression level of miR-30d in the serum of 81 patients with primary MM and 78 healthy donors (HDs). The biological functions of miR-30d were then assessed by CCK-8 assay, flow cytometric analysis of apoptosis and western blot (WB) analysis in U266 cells. Moreover, the confirmation of the target gene of miR-30d was conducted by luciferase reporter assay. Our results indicated that miR-30d expression was significantly downregulated in the serum of patients with primary MM compared with that of the HDs and that it was significantly associated with several clinical indicators of MM. Further cell functional analyses using the U266 cells revealed that miR-30d functions as a tumor suppressor gene in MM by inhibiting cell viability and promoting cell apoptosis. Moreover, miR-30d was confirmed to directly bind to the 3'UTR of its target gene, metadherin (MTDH) and inhibit the activation of the downstream PI3K/Akt signaling pathway. On the whole, the findings of this study indicate that the serum expression level of miR-30d is of great significance to the diagnosis and treatment monitoring of patients with MM. Moreover, miR-30d carries out its antitumor role in U266 cells through the inhibition of the activation of the PI3K/Akt signaling pathway by negatively regulating MTDH, which reveals its potential for use as a therapeutic target for MM.

AIMS: To determine if Metadherin (MTDH) expression levels are positively correlated with the clinical stage of diffuse large B-cell lymphoma (DLBCL) based on MTDH being highly expressed in other type of tumors including melanoma, malignant glioma, breast cancer, and hepatocellular carcinoma. In this study, we investigated the pathologic significance of MTDH and its potential in predicting DLBCL outcomes.
MATERIALS AND METHODS: Tissue samples from 50 patients with DLBCL and 22 patients with lymph node reactive hyperplasia were collected and evaluated using immunohistochemical staining, microscopy, and western blotting. The Kaplan-Meier method and Cox regression model were used for survival analysis of patients.
RESULTS: Our results show that the overexpression of the MTDH protein in tissues was observed in 66% of patients with DLBCL, whereas it was not overexpressed in the patients with reactive hyperplastic lymph nodes. While there was no correlation between MTDH overexpression with age, sex, presence of B symptoms, and lactate dehydrogenase (LDH) levels in patients with DLBCL, this parameter was positively correlated with clinical stages. Moreover, MTDH-negative patients had significantly better prognoses compared with the MTDH-positive patients.
CONCLUSION: Our preliminary study indicates that MTDH may play an important role in the development of DLBCL, and that MTDH overexpression is potentially associated with the clinical progression of DLBCL. In addition, high expression levels of MTDH in tissues was correlated with a poorer prognosis for patients with DLBCL. As such, MTDH may be a potential therapeutic target for specific therapy. However, research on a larger group of patients is needed to verify these preliminary results.

Metadherin (MTDH) is a multifunctional oncogene involved in tumor cell migration and metastasis through regulating a number of oncogenic signaling pathways in various human malignancies. Previous studies have demonstrated that MTDH is overexpressed in human colorectal cancer (CRC) and associated with cancer progression and a poor prognosis. However, the underlying mechanisms remain largely unknown. The present study investigated the expression and role of MTDH in CRC cells as well as the underlying mechanism of this. Western blot analysis and quantitative polymerase chain reaction were conducted to determine protein and mRNA expression of MTDH in three human CRC cell lines. A short hairpin RNA (shRNA) targeting MTDH was introduced into CRC HCT116 cells to stably inhibit MTDH expression. A Cell Counting Kit‑8 assay, colony formation assay, Transwell assay and flow cytometry were used to investigate the effect of MTDH‑knockdown on cell proliferation, migration, apoptosis and cell cycle arrest. Western blotting was performed to examine the protein expression levels of cell growth‑ and apoptosis‑associated genes. The results demonstrated that MTDH was commonly expressed in CRC cell lines. MTDH silencing significantly suppressed cell growth, colony forming ability and migration while inducing the apoptosis of HCT116 cells. In addition, MTDH depletion induced S phase cell cycle arrest in HCT116 cells. Mechanistically, knockdown of MTDH markedly downregulated the expression of phosphorylated protein kinase B, c‑Myc, proliferating cell nuclear antigen and B‑cell lymphoma 2 (Bcl‑2) protein in HCT116 cells, and the expression of p53 and Bcl‑2‑associated X protein was significantly increased compared with the negative control shRNA group (P<0.05), suggesting that MTDH may function through the expression of numerous types of apoptosis‑associated and signaling channel proteins in CRC cells. Taken together, these data indicated that MTDH may serve as a biomarker and candidate therapeutic target for CRC.

MicroRNAs (miRNAs/miRs) serve important roles in regulating gene expression by directly binding to the 3'‑untranslated regions of target genes. Multiple miRNAs are dysregulated in retinoblastoma (RB) and their dysregulation is closely related to RB malignancy. Therefore, exploring the detailed roles of miRNAs in RB is valuable to facilitate the development of effective therapeutic targets for patients with this disease. miRNA‑874‑3p (miR‑874) has been recently reported to be downregulated in several types of human cancer and serves an essential role in cancer progression. However, the expression pattern and detailed roles of miR‑874 in RB, as well as the underlying molecular mechanisms in RB, have not been clearly elucidated. Therefore, this study detected miR‑874 expression in RB tissues and cell lines. The biological roles of miR‑874 in RB were determined and the underlying mechanisms of its actions in RB cells were also examined. This study revealed that miR‑874 expression was aberrantly underexpressed in RB tissues and cell lines. However, returning miR‑874 expression restricted the proliferative and invasive abilities of RB cells. In terms of the underlying mechanism, metadherin (MTDH) was validated as a direct target gene of miR‑874 in RB cells. MTDH inhibition could imitate the inhibitory roles of miR‑874 overexpression in RB cells. Furthermore, forced MTDH expression partially reversed the suppressive effects of miR‑874 on RB cells. In conclusion, this study revealed that miR‑874 may inhibit RB progression by directly targeting MTDH. Restoration of miR‑874 expression may be a novel strategy for preventing the rapid growth and metastasis of RB cells.

MicroRNAs (miRNAs) are important regulators of a variety of biological processes and their dysregulation is closely related to cancer formation and progression. Therefore, examination of aberrantly expressed miRNAs in oral squamous cell carcinoma (OSCC) may provide important clues for the diagnosis and treatment of patients with OSCC. The aim of the present study was to determine miRNA (miR)‑655‑3p expression in OSCC tissues and cell lines, and to investigate the biological roles and mechanisms of miR‑655‑3p associated with OSCC. Data from the present study indicated that miR‑655 expression was significantly downregulated in human OSCC tissues and cell lines. Overexpression of miR‑655 attenuated cell proliferation and invasion in OSCC in vitro. Metadherin (MTDH) mRNA was predicted as a potential target of miR‑655 by bioinformatics analysis, and this was confirmed by luciferase reporter assay, reverse transcription‑quantitative polymerase chain reaction and western blot analysis. In OSCC tissues, MTDH was highly expressed and inversely correlated with miR‑655 expression levels. MTDH overexpression reversed the inhibitory effects of miR‑655 mimics in OSCC cells. Notably, the upregulation of miR‑655 expression inhibited the activation of the phosphatase and tensin homolog (PTEN)/RAC‑α serine/threonine‑protein kinase (AKT) pathway in OSCC cells. Therefore, these results may provide the first evidence that miR‑655 targets MTDH to inhibit proliferation and invasion of OSCC by inhibiting PTEN/AKT signaling. Thus, the restoration of miR‑655 expression may be a novel therapeutic strategy for patients with OSCC.

Breast cancer is a heterogeneous disease, and triple-negative breast cancer (TNBC) continues to be a serious health problem. The potential involvement of lncRNAs in TNBC progression remains unexplored. Here, we demonstrated that LINC01638 is highly expressed in TNBC tissues and cells. LINC01638 maintains the mesenchymal traits of TNBC cells, including an enriched epithelial-mesenchymal transition (EMT) signature and cancer stem cell-like state. LINC01638 knockdown suppresses tumor proliferation and metastasis both in vitro and in vivo. LINC01638 overexpression predicts a poor outcome of breast cancer patients. Mechanistically, LINC01638 interacts with c-Myc to prevent SPOP-mediated c-Myc ubiquitination and degradation. C-Myc transcriptionally enhances MTDH (metadherin) expression and subsequently activates Twist1 expression to induce EMT. Our findings describe LINC01638-mediated signal transduction and highlight the crucial role of LINC01638 in TNBC progression.

Gastric cancer is the main leading cause of cancer-related death worldwide. The aberrant expression of paternally expressed gene 10 (PEG10) is involved in development of a range of cancers. However, the potential biological function and the underling mechanism of PEG10 in human gastric carcinoma are still unknown. Knocking down LncRNA PEG10 might represent a promising therapeutic strategy for the treatment of gastric cancer. The expression of PEG10, miR-3200, and AEG1 in human gastric carcinoma NCI-N87 cells were altered by cell transfection assay. Cell viability, migration, invasion, and apoptosis were determined by trypan blue exclusion, Transwell assay, and flow cytometric analysis, respectively. RNA and protein expression level of gene was analyzed by real-time PCR and Western blot. Luciferase reporter assay was conducted to determine the target gene of miR-3200. JNK and Wnt signal pathway protein expressions were tested by Western blot. The up-regulation of PEG10 was found in clinical samples. PEG10 knockdown effectively inhibited gastric carcinoma cell viability, migration, and invasion, but promoted cell apoptosis. This tumor-suppressing effect of PEG10 knockdown might be realized by up-regulating miR-3200 in vitro and in vivo. AEG1 was a direct target gene of miR-3200. Moreover, miR-3200 might suppress NCI-N87 cells by negative regulating AEG1. Up-regulating miR-3200 effectively blocked JNK and Wnt pathways likely via down-regulating AEG1. PEG10 knockdown played a carcinostatic role via up-regulating miR-3200 and further regulating AEG1 in gastric carcinoma cells, during which process, JNK pathway and Wnt pathway were blocked.

Dysregulation of miR-1297 has been detected in various human cancers, and miR-1297 can function as either an oncogene or tumor suppressor. However, the role of miR-1297 in pancreatic adenocarcinoma has not been previously reported. Here, we investigated miR-1297 expression in pancreatic cancer and the role it plays in the development and metastasis of pancreatic adenocarcinoma. In the present study, MiR-1297 and metadherin (MTDH) expression in pancreatic cancer tissue was detected using quantitative real-time PCR (qRT-PCR) and western blot methods. The CCK-8 assay and EdU incorporation assay were used to analyze the impact of miR-1297 and MTDH on cell proliferation. Flow cytometric and Hoechst 33342 staining methods were used to explore how miR-1297 and MTDH affect cell apoptosis. The Transwell assay and scratch wound healing assay were used to analyze cell migration and invasion capabilities. The dual-luciferase assay was used to confirm that miR-1297 targets MTDH. Here, we found that miR-1297 expression was decreased in pancreatic adenocarcinoma tissues, while MTDH expression was increased in those tissues. Furthermore, western blot and dual-luciferase assay results confirmed that MTDH was a direct target of miR-1297. Additionally, overexpression of miR-1297 or knockdown of MTDH suppressed BxPC-3 and PANC-1 cell proliferation, and upregulation of miR-1297 or suppression of MTDH promoted BxPC-3 and PANC-1 cell apoptosis. Finally, BxPC-3 and PANC-1 cell migration and invasion abilities were suppressed by either overexpression of miR-1297 or downregulation of MTHD. In conclusion, our results suggest that miR-1297 inhibits the growth and metastasis of pancreatic adenocarcinoma by downregulating MTDH expression, and the miR-1297/MTDH pathway is a potential target for treating pancreatic adenocarcinoma.

Accumulating evidence indicates microRNA-216b (miR-216b) plays an important role in the development and progression of various cancers. However, little is known about the function of miR-216b in gliomas. In this study, we aimed to investigate the expression level and functional significance of miR-216b in gliomas. We found that miR-216b was significantly downregulated in glioma specimens and cell lines. Overexpression of miR-216b suppressed the growth and migration of glioma cells, while miR-216b inhibition showed the opposite effects. Astrocyte elevated gene-1 (AEG-1) was predicted as a potential target gene of miR-216b by bioinformatics analysis. A dual-luciferase reporter assay showed that miR-216b could directly target the 3'-untranslated region of AEG-1. RT-qPCR and western blot analysis showed that miR-216 negatively regulated AEG-1 expression in glioma cells. Correlation analysis revealed an inverse correlation between miR-216b and AEG-1 in clinical glioma specimens. miR-216b also regulated the activation of nuclear factor-κB and Wnt signaling in glioma cells. Moreover, restoration of AEG-1 expression partially reversed the inhibitory effect of miR-216b overexpression on glioma cell growth and migration. Overall, these results revealed a tumor suppressive role of miR-216b in glioma tumorigenesis, and identified AEG-1 as a target gene of miR-216b action. Our study suggests that miR-216b can be potentially targeted for the development of novel therapies for gliomas.

Objective: Ovarian carcinoma represents one of the deadliest malignancies among female cancer patients. Astrocyte-elevated gene-1 (AEG-1) participates in the ontogenesis of multiple human malignant diseases. Here we evaluated AEG-1, hypoxia-inducible factor- (HIF-) 1
Patients and Methods: AEG-1, HIF-1
Results: AEG-1, HIF-1
Conclusions: As an independent prognostic factor, AEG-1 was found to be significantly associated with hypoxia in ovarian cancer by regulating the HIF-1alpha/NF-kappaB/VEGF pathway. Therefore, AEG-1 may be useful in determining disease stage and prognosis in ovarian cancer.

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.

BACKGROUND: Accumulating studies have reported the abnormal expression of microRNA-136 (miR-136) in numerous types of human cancer, and its involvement in cancer initiation and progression. However, there are no investigations of miR-136 in osteosarcoma (OS).
OBJECTIVE: To explore the expression pattern, clinical significance and potential roles of miR-136 in OS.
METHODS: miR-136 expression in clinical OS tissues and human OS cell lines were detected by qPCR, and its associations with clinicopathological characteristics of OS patients were statistically analyzed. Then, the effects of miR-136 on OS cell proliferation, migration and invasion were assessed in vitro. Its underling mechanisms were also investigated.
RESULTS: miR-136 expression in OS tissues and cells were dramatically decreased compared with corresponding non-cancerous tissues and cells, respectively. Low miR-136 expression was significantly associated with aggressive clinical features, including the advanced clinical stage, the presence of lung and distant metastasis (all P< 0.05). Additionally, enforced expression of miR-136 obviously inhibited the proliferation, migration and invasion of OS cells in vitro. Mechanistically, metadherin (MTDH) was predicted and verified as a target gene of miR-136. Further functional experiments indicated that the loss of MTDH abrogated the tumor suppressive roles of miR-136 in OS cells.
CONCLUSION: Our findings provide the first evidence that the aberrant expression of miR-136 may be implicated into carcinogenesis and cancer progression of OS. Functionally, miR-136 may inhibit the proliferation, migration and invasion of OS cells via negatively regulating its target gene MTDH. Thus, miR-136-MTDH axis may be a potential therapeutic targets for the treatment of OS.