Comprehensive pan­cancer analysis of MTDH for human tumor prognosis and as an immunological biomarker including breast and kidney cancer.

Metadherin (MTDH), initially discovered in primary astrocytes of the human fetus through rapid subtraction hybridization and labeled as astrocyte elevated gene-1, represents a widely recognized oncogene present in multiple types of cancers. However, the role of MTDH in different types of cancer remains unclear. To address this, a comprehensive analysis of MTDH across various types of cancers was conducted by utilizing multiple databases such as The Cancer Genome Atlas. The present analysis discovered that MTDH exhibits differential expression in different types of cancer and is associated with important factors including tumor mutational burden and microsatellite instability. These findings highlighted the significance of MTDH in the tumor microenvironment and its involvement in the development of immune cells in specific cancers. Furthermore, the results of the present study indicated that the expression of MTDH is strongly correlated with clinical prognosis, mutations and immune cell infiltration. MTDH could serve as a potential indicator of patient prognosis and potentially play a role in modulating the immune system. Given its potential as a novel immunological checkpoint, MTDH may be a viable target for tumor immunotherapy.

Metadherin-driven promotion of cancer stem cell phenotypes and its effect on immunity in hepatocellular carcinoma.

In this editorial we provide commentary on the article published by Wang et al, featured in the recent issue of the World Journal of Gastroenterology in 2024. We focus on the metadherin (MTDH), also known as astrocyte elevated gene-1 or lysine rich CEACAM1, and its effects on cancer stem cells (CSCs) and immunity in hepatocellular carcinoma (HCC). HCC is the most common primary liver cancer and one of the leading causes of cancer-related deaths worldwide. Most HCC cases develop in the context of liver cirrhosis. Among the pivotal mechanisms of carcinogenesis are gene mutations, dysregulation of diverse signaling pathways, epigenetic alterations, hepatitis B virus-induced hepatocarcinogenesis, chronic inflammation, impact of tumor microenvironment, oxidative stress. Over the years, extensive research has been conducted on the MTDH role in various tumor pathologies, such as lung, breast, ovarian, gastric, hepatocellular, colorectal, renal carcinoma, neuroblastoma, melanoma, and leukemias. Specifically, its involvement in tumor development processes including transformation, apoptosis evasion, angiogenesis, invasion, and metastasis via multiple signaling pathways. It has been demonstrated that knockdown or knockout of MTDH disrupt tumor development and metastasis. In addition, numerous reports have been carried out regarding the MTDH influence on HCC, demonstrating its role as a predictor of poor prognosis, aggressive tumor phenotypes prone to metastasis and recurrence, and exhibiting significant potential for therapy resistance. Finally, more studies finely investigated the influence of MTDH on CSCs. The CSCs are a small subpopulation of tumor cells that sharing traits with normal stem cells like self-renewal and differentiation abilities, alongside a high plasticity that alters their phenotype. Beyond their presumed role in tumor initiation, they can drive also disease relapse, metastasis, and resistance to chemo and radiotherapy.

TurboID-Based IRE1 Interactome Reveals Participants of the Endoplasmic Reticulum-Associated Protein Degradation Machinery in the Human Mast Cell Leukemia Cell Line HMC-1.2.

The unfolded protein response is an intricate system of sensor proteins in the endoplasmic reticulum (ER) that recognizes misfolded proteins and transmits information via transcription factors to either regain proteostasis or, depending on the severity, to induce apoptosis. The main transmembrane sensor is IRE1α, which contains cytoplasmic kinase and RNase domains relevant for its activation and the mRNA splicing of the transcription factor XBP1. Mast cell leukemia (MCL) is a severe form of systemic mastocytosis. The inhibition of IRE1α in the MCL cell line HMC-1.2 has anti-proliferative and pro-apoptotic effects, motivating us to elucidate the IRE1α interactors/regulators in HMC-1.2 cells. Therefore, the TurboID proximity labeling technique combined with MS analysis was applied. Gene Ontology and pathway enrichment analyses revealed that the majority of the enriched proteins are involved in vesicle-mediated transport, protein stabilization, and ubiquitin-dependent ER-associated protein degradation pathways. In particular, the AAA ATPase VCP and the oncoprotein MTDH as IRE1α-interacting proteins caught our interest for further analyses. The pharmacological inhibition of VCP activity resulted in the increased stability of IRE1α and MTDH as well as the activation of IRE1α. The interaction of VCP with both IRE1α and MTDH was dependent on ubiquitination. Moreover, MTDH stability was reduced in IRE1α-knockout cells. Hence, pharmacological manipulation of IRE1α-MTDH-VCP complex(es) might enable the treatment of MCL.

Metadherin promotes stem cell phenotypes and correlated with immune infiltration in hepatocellular carcinoma.

BACKGROUND: Metadherin (MTDH) is a key oncogene in most cancer types, including hepatocellular carcinoma (HCC). Notably, MTDH does not affect the stemness pheno-type or immune infiltration of HCC. AIM: To explore the role of MTDH on stemness and immune infiltration in HCC. METHODS: MTDH expression in HCC tissues was detected using TCGA and GEO databases. Immunohistochemistry was used to analyze the tissue samples. MTDH was stably knocked down or overexpressed by lentiviral transfection in the two HCC cell lines. The invasion and migration abilities of HCC cells were evaluated using Matrigel invasion and wound healing assays. Next, we obtained liver cancer stem cells from the spheroids by culturing them in a serum-free medium. Gene expression was determined by western blotting and quantitative reverse transcri-ption PCR. Flow cytometry, immunofluorescence, and tumor sphere formation assays were used to characterize stem-like cells. The effects of MTDH inhibition on tumor growth were evaluated in vivo. The correlation of MTDH with immune cells, immunomodulators, and chemokines was analyzed using ssGSEA and TISIDB databases. RESULTS: HCC tissues expressed higher levels of MTDH than normal liver tissues. High MTDH expression was associated with a poor prognosis. HCC cells overexpressing MTDH exhibited stronger invasion and migration abilities, exhibited a stem cell-like phenotype, and formed spheres; however, MTDH inhibition attenuated these effects. MTDH inhibition suppressed HCC progression and CD133 expression in vivo. MTDH was positively correlated with immature dendritic, T helper 2 cells, central memory CD8+ T, memory B, activated dendritic, natural killer (NK) T, NK, activated CD4+ T, and central memory CD4+ T cells. MTDH was negatively correlated with activated CD8+ T cells, eosinophils, activated B cells, monocytes, macrophages, and mast cells. A positive correlation was observed between the MTDH level and CXCL2 expression, whereas a negative correlation was observed between the MTDH level and CX3CL1 and CXCL12 expression. CONCLUSION: High levels of MTDH expression in patients with HCC are associated with poor prognosis, promoting tumor stemness, immune infiltration, and HCC progression.

Metadherin inhibits chemosensitivity of triple-negative breast cancer to paclitaxel via activation of AKT/GSK-3ß signaling pathway.

Triple-negative breast cancer (TNBC) has an aggressive clinical course, and paclitaxel (PTX)-based chemotherapy remains the main therapeutic drug. Metadherin (MTDH) acts as an oncogene that regulates proliferation, invasion, metastasis, and chemoresistance. This study aimed to investigate whether TNBC chemosensitivity to PTX was related to the MTDH/AKT/glycogen synthase kinase-3beta (GSK-3ß) pathway. Clinical baseline characteristics and immunohistochemistry (IHC) were used to evaluate the expression and prognosis of MTDH and AKT (protein kinase B, PKB) in TNBC patient samples. MTDH shRNA, MTDH overexpression vector, MK-2206, and PTX intervention were used in cell models and mouse tumor-bearing models. Afterwards, mRNA and protein levels were assessed using quantitative real-time polymerase chain reaction and Western blot. Evaluate the level of tumor cell apoptosis and cell cycle using flow cytometry. Cell viability was detected using Cell Count Kit 8. The in vivo imaging system is used to analyze the growth of tumors. We found that higher expression of MTDH or AKT resulted in poorer disease-free survival and a lower Miller-Payne grade. MTDH promotes cell proliferation and increases p-AKT and p-GSK-3ß expression in TNBC cells. Notably, suppression of AKT terminated MTDH overexpression-induced cell proliferation and apoptosis. MTDH knockdown or the AKT inhibitor MK2206 reduced the p-AKT and p-GSK-3ß ratio, reduced cell viability and proliferation, increased cell apoptosis, and increased chemosensitivity to PTX. In vivo, xenograft tumors of an MTDH knockdown+MK2206 group treated with PTX were the smallest compared to other groups. In short, MTDH inhibits TNBC chemosensitivity to PTX by activating the AKT/GSK-3ß signaling pathway.

Cheminformatics and biomolecular dynamics studies towards the discovery of anti-staphylococcal nuclease domain-containing 1 (SND1) inhibitors to treat metastatic breast cancer.

Metastatic breast cancer is a prime health concern and leading health burden across the globe. Previous efforts have shown that protein-protein interaction between Metadherin and Staphylococcal nuclease domaincontaining 1 (SND1) promotes initiation of breast cancer, progression, therapy resistance and metastasis. Therefore, small drug molecules that can interrupt the Metadherin and SND1 interaction may be ideal to suppress tumor growth, metastasis and increases chemotherapy sensitivity of triple negative breast cancer. Here, in this study, structure based virtual screening was conducted against the reported active site of SND1 enzyme, which revealed three promising lead molecules from Asinex library. These compounds were; BAS_00381028, BAS_00327287, and BAS_01293454 with binding energy score -10.25 kcal/mol, -9.65 kcal/mol and -9.32 kcal/mol, respectively. Compared to control (5-chloro-2-methoxy-N-([1,2,4]triazolo[1,5-a]pyridin-8-yl)benzene-1-sulfonamide) the lead molecules showed robust hydrophilic and hydrophobic interactions with the enzyme and revealed stable docked conformation in molecular dynamics simulation. During the simulation time, the compounds reported stable dynamics with no obvious fluctuation in binding mode and interactions noticed. The mean root mean square deviation (RMSD) of BAS_00381028, BAS_00327287, and BAS_01293454 complexes were 1.87 Å, 1.75 Å, 1.34 Å, respectively. Furthermore, the MM/GBSA analysis was conduction on the simulation trajectories of complexes that unveiled binding energy score of -19.25 kcal/mol, -27.03 kcal/mol, -34.6 kcal/mol and -29.61 kcal/mol for control, BAS_00381028, BAS_00327287, and BAS_01293454, respectively. In MM/PBSA, the binding energy value of for control, BAS_00381028, BAS_00327287, and BAS_01293454 was -20.45 kcal/mol, -27.89 kcal/mol, -36.41 kcal/mol and -32.01 kcal/mol, respectively. Additionally, the compounds were classified as druglike and have favorable pharmacokinetic properties. The compounds were predicted as promising leads and might be used in experimental investigation to study their anti-SND1 activity.

[Retracted] MicroRNA­758 inhibits tumorous behavior in tongue squamous cell carcinoma by directly targeting metadherin.

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that certain of the Transwell invasion assay data shown in Fig. 5E were strikingly similar to data appearing in different form in other articles written by different authors at different research institutes, several of which have already been retracted. Owing to the fact that the contentious data in the above article had already been published prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they accepted the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 19: 1883­1890, 2019; DOI: 10.3892/mmr.2019.9805].

The Proteome Landscape of Human Placentas for Monochorionic Twins with Selective Intrauterine Growth Restriction.

In perinatal medicine, intrauterine growth restriction (IUGR) is one of the greatest challenges. The etiology of IUGR is multifactorial, but most cases are thought to arise from placental insufficiency. However, identifying the placental cause of IUGR can be difficult due to numerous confounding factors. Selective IUGR (sIUGR) would be a good model to investigate how impaired placentation affects fetal development, as the growth discordance between monochorionic twins cannot be explained by confounding genetic or maternal factors. Herein, we constructed and analyzed the placental proteomic profiles of IUGR twins and normal cotwins. Specifically, we identified a total of 5481 proteins, of which 233 were differentially expressed (57 up-regulated and 176 down-regulated) in IUGR twins. Bioinformatics analysis indicates that these differentially expressed proteins (DEPs) are mainly associated with cardiovascular system development and function, organismal survival, and organismal development. Notably, 34 DEPs are significantly enriched in angiogenesis, and diminished placental angiogenesis in IUGR twins has been further elaborately confirmed. Moreover, we found decreased expression of metadherin (MTDH) in the placentas of IUGR twins and demonstrated that MTDH contributes to placental angiogenesis and fetal growth in vitro. Collectively, our findings reveal the comprehensive proteomic signatures of placentas for sIUGR twins, and the DEPs identified may provide in-depth insights into the pathogenesis of placental dysfunction and subsequent impaired fetal growth.

Metadherin Regulates Inflammatory Breast Cancer Invasion and Metastasis.

Inflammatory breast cancer (IBC) is one of the most lethal subtypes of breast cancer (BC), accounting for approximately 1-5% of all cases of BC. Challenges in IBC include accurate and early diagnosis and the development of effective targeted therapies. Our previous studies identified the overexpression of metadherin (MTDH) in the plasma membrane of IBC cells, further confirmed in patient tissues. MTDH has been found to play a role in signaling pathways related to cancer. However, its mechanism of action in the progression of IBC remains unknown. To evaluate the function of MTDH, SUM-149 and SUM-190 IBC cells were edited with CRISPR/Cas9 vectors for in vitro characterization studies and used in mouse IBC xenografts. Our results demonstrate that the absence of MTDH significantly reduces IBC cell migration, proliferation, tumor spheroid formation, and the expression of NF-κB and STAT3 signaling molecules, which are crucial oncogenic pathways in IBC. Furthermore, IBC xenografts showed significant differences in tumor growth patterns, and lung tissue revealed epithelial-like cells in 43% of wild-type (WT) compared to 29% of CRISPR xenografts. Our study emphasizes the role of MTDH as a potential therapeutic target for the progression of IBC.

[Retracted] MicroRNA­675 inhibits cell proliferation and invasion in melanoma by directly targeting metadherin.

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that the western blotting data shown in Fig. 5A and the cell migration and invasion assay data shown in Fig. 5C were strikingly similar to data appearing in different form in other articles by different authors at different research institutes, several of which have been retracted. Owing to the fact that the contentious data in the above article were already under consideration for publication, or had already been published, prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. After having been in contact with the authors, they agreed with the decision to retract the paper. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 17: 3372­3379, 2018; DOI: 10.3892/mmr.2017.8264].

Proteomes from AMPK-inhibited peripheral blood mononuclear cells suppress the progression of breast cancer and bone metastasis.

Background: During a developmental process, embryos employ varying tactics to remove unwanted cells. Using a procedure analogous to some of the embryonic cells, we generated a tumor-eliminating conditioned medium (CM) from AMPK-inhibited lymphocytes and monocytes in peripheral blood mononuclear cells (PBMCs). Methods: AMPK signaling was inhibited by the application of a pharmacological agent, Dorsomorphin, and the therapeutic effects of their conditioned medium (CM) were evaluated using in vitro cell cultures, ex vivo breast cancer tissues, and a mouse model of mammary tumors and tumor-induced osteolysis. The regulatory mechanism was evaluated using mass spectrometry-based proteomics, Western blotting, immunoprecipitation, gene overexpression, and RNA interference. Results: While AMPK signaling acted mostly anti-tumorigenic, we paradoxically inhibited it to build induced tumor-suppressing cells and their tumor-eliminating CM. In a mouse model of breast cancer, the application of AMPK-inhibited lymphocyte-derived CM reduced mammary tumors additively to a chemotherapeutic agent, Taxol. It also prevented bone loss in the tumor-bearing tibia. Furthermore, the application of CM from the patient-derived peripheral blood diminished ex vivo breast cancer tissues isolated from the same patients. Notably, proteins enriched in CM included Moesin (MSN), Enolase 1 (ENO1), and polyA-binding protein 1 (PABPC1), which are considered tumorigenic in many types of cancer. The tumor-suppressing actions of MSN and ENO1 were at least in part mediated by Metadherin (Mtdh), which is known to promote metastatic seeding. Conclusion: We demonstrated that PBMCs can be used to generate tumor-suppressive proteomes, and extracellular tumor-suppressing proteins such as MSN, ENO1, and PABPC1 are converted from tumor-promoting factors inside cancer cells. The results support the possibility of developing autologous blood-based therapy, in which tumor-suppressing proteins are enriched in engineered PBMC-derived CM by the inhibition of AMPK signaling.

[Corrigendum] The targeting of MTDH by miR­145­5p or miR­145­3p is associated with prognosis and regulates the growth and metastasis of prostate cancer cells.

Following the publication of the above article, an interested reader drew to the authors' attention that the Transwell invasion assay images in Fig. 3B on p. 1961 representing the Con/PWR­1E and the PC­3/siMTDH experiments contained overlapping sections, such that they appeared to have been derived from the same original source, even though they were intending to have shown the results from differently performed experiments. Similarly, in Fig. 8A on p. 1965, the representative images selected for the PC­3/miR­145­3p and LNCaP/miR­145­3p data panels were also found to contain overlapping sections. After having consulted their original data, the authors realized that these errors had occurred while compiling the affected figure parts. The revised versions of Figs. 3 and 8, containing the data from one of the repeated experiments in Fig. 3B and 8A, are shown on the next two pages. Concerns about the western blots featured in Figs. 4C and D and 9F were also raised by the interested reader; upon querying these with the authors, however, they were able to provide the full blots in these cases, thereby confirming their authenticity. The authors regret that these errors went unnoticed prior to publication, and thank the Editor of International Journal of Oncology for allowing them the opportunity to publish this corrigendum. All the authors agree with the publication of this corrigendum; furthermore, they also apologize to the readership of the journal for any inconvenience caused. [International Journal of Oncology 54: 1955­1968, 2019; DOI: 10.3892/ijo.2019.4782].

Identification of Small Inhibitors for Human Metadherin, an Oncoprotein, through in silico Approach.

AIMS: Cancer is a disease that takes lives of thousands of people each year. There are more than 100 different types of cancers known to man. This fatal disease is one of the leading causes of death today. BACKGROUND: Astrocyte elevated gene-1(AEG-1)/Metadherin (MTDH) activates multiple oncogenic signaling pathways and leads to different types of cancers. MTDH interacting with staphylococcal nuclease domain containing 1(SND1) supports the survival and growth of mammary epithelial cells under oncogenic conditions. OBJECTIVE: Silencing MTDH or SND1 individually or disrupting their interaction compromises the tumorigenic potential of tumor-initiating cells. The aim of our present study was to investigate novel interactions of staphylococcal nuclease domain containing 1 (SND1) binding domain of AEG-1/MTDH with different lead compounds through molecular docking approach using MOE software. METHODS: Molecular docking was done by docking the ChemBridge database against important residues of MTDH involved in interaction with SND1. After docking the whole ChemBridge database, the top 200 interactive compounds were selected based on docking scores. After applying Lipinski's rule, all the remaining chosen compounds were studied on the basis of binding affinity, binding energy, docking score and protein-ligand interactions. Finally, 10 compounds showing multiple interactions with different amino acid residues were selected as the top interacting compounds. RESULTS: Three compounds were selected for simulation studies after testing these compounds using topkat toxicity and ADMET studies. The simulation study indicated that compound 32538601 is a lead compound for inhibiting MTDH-SND1 complex formation. CONCLUSION: These novels, potent inhibitors of MTDH-SND1 complex can ultimately help us in controlling cancer up to some extent.

[Retracted] MicroRNA­655 suppresses cell proliferation and invasion in oral squamous cell carcinoma by directly targeting metadherin and regulating the PTEN/AKT pathway.

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that the data in the centre panel shown for the cell invasion assays in Fig. 2C were strikingly similar to data appearing in different form in other articles by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 18: 3106­3114, 2018; DOI: 10.3892/mmr.2018.9292].

[Retracted] MicroRNA­874 prohibits the proliferation and invasion of retinoblastoma cells by directly targeting metadherin.

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the data showing cell invasion assay experiments in Figs. 2C, 4D and 5D were strikingly similar to data that had appeared in different form in other articles by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 18: 3099­3105, 2018; DOI: 10.3892/mmr.2018.9295].

Effects of miRNA-30a-5p and metadherin on proliferation, invasion and migration abilities of breast cancer cells / 肿瘤研究与临床

Objective:To investigate the effects of miRNA-30a-5p (miR-30a-5p) and metadherin (MTDH) on the proliferation, invasion and migration abilities of human breast cancer cells in vitro.Methods:The expression of MTDH in cancer and paracancerous tissues of 112 breast cancer patients in the database and miR-30a-5p in cancer and paracancerous tissues of 103 breast cancer patients in the database were analyzed using data from The Cancer Genome Atlas (TCGA) database. Pearson correlation analysis was used to analyze the correlation between miR-30a-5p and MTDH in 1 222 breast cancer patients in the database; the data were updated to August 2022. Breast cancer MDA-MB-231 cells were divided into negative control group (transfected with negative control sequence), miR-30a-5p overexpression group (transfected with miR-30a-5p mimics), siMTDH group [transfected with small interfering RNA against MTDH (siMTDH)], siMTDH+miR-30a-5p overexpression group (transfected with both siMTDH and miR-30a-5p mimics); cell proliferation ability was detected by methyl thiazol tetrazolium (MTT) assay, cell migration ability was detected by cell scratch assay, cell invasion ability was detected by Transwell assay. The relative expressions of miR-30a-5p, MTDH, matrix metalloproteinase (MMP)-2, MMP-9, vimentin and β-catenin mRNA in cells were detected by quantitative real-time fluorescence polymerase chain reaction (qRT-PCR), and the expressions of MTDH, N-cadherin (N-cad), β-catenin, Snail and MMP-9 proteins were detected by Western blotting.Results:In the TCGA database, MTDH expression level was higher and miR-30a-5p expression level was lower in breast cancer tissues compared with paracancerous tissues, and the differences were statistically significant (both P < 0.001). There was a negative correlation between MTDH and miR-30a-5p expressions in 1 222 patients with breast cancer ( r=-0.134, P < 0.001). Compared with the negative control group, the cell proliferation ability was reduced in both siMTDH group and miR-30a-5p overexpression group at 24, 48 and 72 h (all P < 0.001). The cell scratch healing rate in miR-30a-5p overexpression group and siMTDH group was lower than that in negative control group [(61.6±1.6)%, (54.7±5.9)% vs. (80.3±3.0)%] (both P < 0.05). Compared with the negative control group, The number of migrated cells in miR-30a-5p overexpression group and siMTDH group was less than that in negative control group (881±50, 725±63 vs. 1 172±66) (both P < 0.05). Compared with the negative control group, the relative expressions of MMP-2, MMP-9, vimentin and β-catenin mRNA were all down-regulated in MDA-MB-231 cells of miR-30a-5p overexpression group and siMTDH group (all P < 0.05). Compared with the negative control group, the relative expressions of N-cad, β-catenin, Snail and MMP-9 proteins were down-regulated in MDA-MB-231 cells of miR-30a-5p overexpression group and siMTDH group (all P < 0.05). There was no statistical difference in the number of migrated MDA-MB-231 cells between siMTDH+miR-30a-5p overexpression group and siMTDH group (476±5 vs. 389±46, t = 3.37, P = 0.078). There was no statistical difference in the number of migrated cells between siMTDH+miR-30a-5p overexpression group and miR-30a-5p overexpression group (476±5 vs. 477±22, t = 0.02, P = 0.983). Conclusions:The expression of miR-30a-5p is negatively correlated with the expression of MTDH in breast cancer tissues, and either overexpression of miR-30a-5p or silence of MTDH in breast cancer MDA-MB-231 cells in vitro can inhibit cell proliferation, invasion and migration, but MTDH may not be a target gene of miR-30a-5p.

A study on mechanism of lncRNA-mediated SNHG5/miR-26a-5p/MTDH signal axis promoting metastasis of colorectal cancer / 中国癌症杂志

Background and purpose: Long non-coding RNA small nucleolar RNA host gene 5 (lncRNA SNHG5) plays a cancer-promoting role in many cancers, however its effect on colorectal cancer (CRC) and its regulatory mechanism are not clear. This study aimed to explore the mechanism of lncRNA SNHG5/miR-26a-5p/metadherin (MTDH) signal axis promoting metastasis of CRC. Methods: The data of The Cancer Genome Atlas (TCGA) database was analyzed, the abnormal expression of lncRNA in CRC was explored and analyzed the survival. Samples of CRC, paracancerous tissues and complete clinical data of patients who underwent surgical resection from October 2020 to October 2021 were collected. The expression levels of SNHG5 and miR-26a-5p in lncRNA were detected by real-time fluorescence quantitative polymerase chain reaction (RTFQ-PCR), and the expression level of MTDH was detected by immunohistochemistry. The relationship between the relative expression level of lncRNA SNHG5 in CRC and clinicopathological features and survival time was analyzed. The effects of lncRNA SNHG5 on the proliferation, migration and invasion of CRC cells were detected by cell counting kit-8 (CCK-8), clone formation, scratching assays, transwell test and in vivo xenotransplantation. The relationship between CRC cell metastasis, the expression level of epithelial-mesenchymal transition related molecules and lncRNA SNHG5 expression level by Western blot and immunohistochemical detection were explored. The physical interaction between SNHG5 and miR-26a-5p, MTDH and miR-26a-5p was studied by RNA pull-down test, double luciferase reporter gene detection and RNA co-immunoprecipitation. The functional relationship among the three was verified by CCK-8, EdU and transwell experiments. The effect of SNHG5, miR-26a-5p and MTDH expression on migration and invasion related molecules was analyzed by Western blot. Results: The results of TCGA database analysis showed that lncRNA SNHG5 was significantly upregulated in CRC. The results of RTFQ-PCR and immunohistochemistry showed that the levels of lncRNA SNHG5 and MTDH in CRC tissues were significantly upregulated (P＜0.05), the level of miR-26a-5p was decreased (P＜0.05), and the level of MTDH in samples with high expression of SNHG5 was also increased. The expression of lncRNA SNHG5 in CRC tissues with serosa and extraserosal invasion, distant metastasis, lymph node metastasis and TNM stage Ⅲ was significantly higher compared with subserosal invasion, no distant metastasis and lymph node metastasis and TNM stage Ⅰ-Ⅱ (P＜0.05). The results of survival analysis showed that the high expression of lncRNA SNHG5 was significantly correlated with overall survival rate (P＜0.05). Overexpression of lncRNA SNHG5 could enhance the proliferation, clone formation, migration and invasion of CRC cells, promote the growth and lung metastasis of transplanted tumor, increase the relative expression level of Ki-67 proliferation index and vimentin (P＜0.05), and decrease the relative expression level of E-cadherin (P＜0.05). However, the development of CRC cells was inhibited after inhibition of lncRNA SNHG5 expression. RNA pull-down test, double luciferase reporter gene detection and RNA co-immunoprecipitation confirmed the physical interaction between SNHG5 and miR-26a-5p, MTDH and miR-26a-5p. Upregulation of miR-26a-5p or downregulation of MTDH expression in lncRNA SNHG5 overexpressed cells partially reversed the effects of lncRNA SNHG5 on proliferation, migration, invasion and expression of related molecules in CRC cells. Conclusion: LncRNA SNHG5 is upregulated in CRC tissues and cells, and its high expression is related to tumor progression and poor survival. It can be used as a molecular sponge of miR-26a-5p to regulate the expression of MTDH to promote the proliferation and metastasis of SW620 cells.

[Retracted] MicroRNA­379 inhibits cell proliferation and invasion in glioma via targeting metadherin and regulating PTEN/AKT pathway.

Following the publication of this paper, it was drawn to the Editors' attention by a concerned reader that certain of the data shown for the cell migration and invasion assays in Figs. 2C and 4C were strikingly similar to data appearing in different form in other articles by different authors. Owing to the fact that the contentious data in the above article had already been published elsewhere, or were already under consideration for publication, prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 17: 4049­4056, 2018; DOI: 10.3892/mmr.2017.8361].

Miat and interacting protein Metadherin maintain a stem-like niche to promote medulloblastoma tumorigenesis and treatment resistance.

Long noncoding RNAs (lncRNAs) play essential roles in the development and progression of many cancers. However, the contributions of lncRNAs to medulloblastoma (MB) remain poorly understood. Here, we identify Miat as an lncRNA enriched in the sonic hedgehog group of MB that is required for maintenance of a treatment-resistant stem-like phenotype in the disease. Loss of Miat results in the differentiation of tumor-initiating, stem-like MB cells and enforces the differentiation of tumorigenic stem-like MB cells into a nontumorigenic state. Miat expression in stem-like MB cells also facilitates treatment resistance by down-regulating p53 signaling and impairing radiation-induced cell death, which can be reversed by therapeutic inhibition of Miat using antisense oligonucleotides. Mechanistically, the RNA binding protein Metadherin (Mtdh), previously linked to resistance to cytotoxic therapy in cancer, binds to Miat in stem-like MB cells. Like the loss of Miat, the loss of Mtdh reduces tumorigenicity and increases sensitivity to radiation-induced death in stem-like MB cells. Moreover, Miat and Mtdh function to regulate the biogenesis of several microRNAs and facilitate tumorigenesis and treatment resistance. Taken together, these data reveal an essential role for the lncRNA Miat in sustaining a treatment-resistant pool of tumorigenic stem-like MB cells.

LOC102553417 silencing facilitates the apoptosis of hepatic stellate cells via the miR­30e/MTDH axis.

Hepatic fibrosis is an inevitable pathological process in the progression of multiple chronic liver diseases and remains a major challenge in the treatment of liver diseases. The purpose of the present study was to demonstrate whether silencing of the long non­coding RNA LOC102553417 promoted hepatic stellate cell (HSC) apoptosis via the microRNA (miR)­30e/metadherin (MTDH) axis. A LOC102553417 silencing lentivirus was constructed and transduced into HSC­T6 cells. After confirming the silencing efficiency by reverse transcription­quantitative PCR, cell proliferation was assessed using the Cell Counting Kit­8 assay and apoptosis was assessed using flow cytometry. The interaction between LOC102553417 and miR­30e, and that between miR­30e and MTDH, was demonstrated using the dual­luciferase reporter assay and RNA binding protein immunoprecipitation. The apoptosis of HSC­T6 cells was detected after transfection of miR­30e mimics and inhibitors with or without silencing LOC102553417. Silencing of LOC102553417 curbed HSC­T6 cell proliferation and expedited their apoptosis. LOC102553417 was demonstrated to target miR­30e, whereas miR­30e targeted MTDH. In addition, LOC102553417 silencing significantly upregulated miR­30e expression levels, and significantly downregulated MTDH mRNA and protein expression levels, which resulted in a significantly reduced p­Akt/Akt ratio and significantly elevated p53 protein expression levels. Transfection with miR­30e mimic alone significantly enhanced HSC­T6 cell apoptosis and inhibits LOC102553417 and MTDH expressions, In addition, miR­30e mimic expedites the apoptosis of HSCs stimulated by LOC102553417 silencing; consistent results were obtained by reverse validation of miR­30e inhibitor. In conclusion, the present study demonstrated that LOC102553417 silencing stimulated the apoptosis of HSCs via the miR­30e/MTDH axis.