Guardian of Genetic Messenger-RNA-Binding Proteins

Oncogenic role of RNA-binding protein GNL2 in glioma: Promotion of tumor development through enhancing protein synthesis

RNA-binding proteins (RBPs) are aberrantly expressed in various diseases, including glioma. In the present study, the role and mechanism of RBPs in glioma were investigated. Differentially expressed genes (DEGs) in glioma were screened from public databases and overlapping genes between DEGs and RBPs were selected in a bioinformatics analysis to identify the hub gene. Next, evaluation of expression, survival analysis and cell experiments were performed to examine the impact of the hub gene on glioma. Through bioinformatics analysis, G protein nucleolar 2 (GNL2), programmed cell death 11 (PDCD11) and ribosomal protein S6 (RPS6) were identified as potential biomarkers in glioma prognosis and GNL2 was chosen as the hub gene for further investigation. GNL2 was increased in glioma tissues and related to poor survival outcomes. Cell experiments revealed that GNL2 knockdown inhibited glioma cell growth, migration and invasion. In addition, GNL2 was found to affect the overall protein synthesis of ribosomal protein L11 in glioma cells. In conclusion, GNL2, PDCD11 and RPS6 may serve as potential biomarkers in glioma prognosis. Importantly, GNL2 acts as an oncogene in glioma and it enhances protein synthesis to promote the development of brain glioma.

Integrated Analysis of miRNA and mRNA Regulation Network in Hypertension

Hypertension is the most common chronic disease. Early diagnosis is helpful for early medical intervention. The miRNAs and the messenger RNAs (mRNAs) network may be valuable disease diagnosis markers. We aimed to explore the diagnostic value of the miRNA-mRNA network for hypertension patients. Data of miRNAs and mRNAs expression were obtained from the Gene Expression Omnibus database. The weighted gene co-expression network analysis was performed to screen hypertension-related gene modules, and these genes undergone functional enrichment analysis using "clusterProfiler" package. Differential expression analysis was applied on miRNAs expression profiles using "limma" package. TargetScanHuman and miRDB databases were used to select target mRNAs. Cytoscape software was used to visualize the miRNA-mRNA regulation network. P value < 0.05 was considered statistically significant after t test. There were 123 screened mRNAs which were enriched in 161 Gene ontology (GO) terms and 14 Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways. Thirty-five differentially expressed miRNAs (DEMs) are found in the GSE75670. Totally 36 miRNA-mRNA pairs were obtained after the integrated analysis, and three mRNAs and the hsa-miRNA-5589-5p were identified as key joints. Hub genes, KIAA0513, ARID3A and LRPAP1, and key hsa-miRNA-5589-5p are potential diagnostic biomarkers for hypertension. Our findings are promising in the clinical application, conducive to early detection and prompt intervention of hypertension.

The Role of ESRP1 in the Regulation of PHGDH in Estrogen Receptor-Positive Breast Cancer

Resistance to hormone therapy leads to a recurrence of estrogen receptor-positive breast cancer. We have demonstrated that the epithelial splicing regulatory protein 1 (ESRP1) significantly affects cell/tumor growth and metabolism and is associated with a poor prognosis in this breast cancer subtype. In this study, we aimed to investigate the ESRP1 protein-messenger RNA (mRNA) interaction in hormone therapy-resistant breast cancer. RNA-binding protein immunoprecipitation (RIP) followed by Clariom D (Applied Biosystems/Thermo Fisher Scientific) transcriptomics microarray (RIP-Chip) was performed to identify mRNA-binding partners of ESRP1. The integration of RIP-Chip and immunoprecipitation-mass spectrometry analyses identified phosphoglycerate dehydrogenase (PHGDH), a key metabolic enzyme, as a binding partner of ESRP1 in hormone-resistant breast cancer. Bioinformatic analysis showed ESRP1 binding to the 5' untranslated region of PHGDH. RNA electrophoresis mobility shift assay and RIP-quantitative reverse transcription-polymerase chain reaction further validated the ESRP1-PHGDH binding. In addition, knockdown of ESRP1 decreased PHGDH mRNA stability significantly, suggesting the posttranscriptional regulation of PHGDH by ESRP1. The presence or absence of ESRP1 levels significantly affected the stability in tamoxifen-resistant LCC2 and fulvestrant-resistant LCC9 cells. PHGDH knockdown in tamoxifen-resistant cells further reduced the oxygen consumption rate (ranging from P = .005 and P = .02), mimicking the effects of ESRP1 knockdown. Glycolytic parameters were also altered (ranging P = .001 and P = .005). ESRP1 levels did not affect the stability of PHGDH in T-47D cells, although knockdown of PHGDH affected the growth of these cells. In conclusion, to our knowledge, this study, for the first time, reports that ESRP1 binds to the 5' untranslated region of PHGDH, increasing its mRNA stability in hormone therapy-resistant estrogen receptor-positive breast cancer. These findings provide evidence for a novel mechanism of action of RNA-binding proteins such as ESRP1. These new insights could assist in developing novel strategies for the treatment of hormone therapy-resistant breast cancer.

Metastatic tumor antigen 1 contributes to hepatocarcinogenesis posttranscriptionally through RNA-binding function

BACKGROUND AND AIMS

Both nuclear and cytoplasmic overexpression of metastatic tumor antigen 1 (MTA1) contributes to tumorigenesis of HCC. Most studies have focused on nuclear MTA1 whose function is mainly a chromatin modifier regulating the expression of various cancer-promoting genes. By contrast, the molecular mechanisms of cytoplasmic MTA1 in carcinogenesis remain elusive. Here, we reveal a role of MTA1 in posttranscriptional gene regulation.

APPROACH AND RESULTS

We conducted the in vitro and in vivo RNA-protein interaction assays indicating that MTA1 could bind directly to the 3'-untranslated region of MYC RNA. Mutation at the first glycine of the conserved GXXG loop within a K-homology II domain-like structure in MTA1 (G78D) resulted in the loss of RNA-binding activity. We used gain- and loss-of-function strategy showing that MTA1, but not the G78D mutant, extended the half-life of MYC and protected it from the lethal -7-mediated degradation. The G78D mutant exhibited lower activity in promoting tumorigenesis than wild-type in vitro and in vivo. Furthermore, RNA-immunoprecipitation sequencing analysis demonstrated that MTA1 binds various oncogenesis-related mRNAs besides MYC . The clinical relevance of cytoplasmic MTA1 and its interaction with MYC were investigated using HBV-HCC cohorts with or without early recurrence. The results showed that higher cytoplasmic MTA1 level and MTA1- MYC interaction were associated with early recurrence.

CONCLUSIONS

MTA1 is a generic RNA-binding protein. Cytoplasmic MTA1 and its binding to MYC is associated with early recurrence in patients with HBV-HCC. This function enables it to regulate gene expression posttranscriptionally and contributes to hepatocarcinogenesis.

Overexpression of lncRNA HCP5 in human umbilical cord mesenchymal stem cell-derived exosomes promoted the proliferation and inhibited the apoptosis of ovarian granulosa cells via the musashi RNA-binding protein 2/oestrogen receptor alpha 1 axis

HCP5 has been reported to be downregulated in ovarian granulosa cells (OGCs) and to facilitate cell proliferation. Human umbilical cord mesenchymal stem cell exosome (hucMSCs-exo) treatment can prevent OGCs apoptosis in vitro. However, the functional mechanism of HCP5 and hucMSCs-exo requires further exploration. Fluorescence-activated cell sorting (FACS) was performed to measure the expression of markers related to hucMSCs. The osteogenic and adipogenic potential of hucMSCs was measured by alkaline phosphatase (ALP) and Alizarin red and by oil red-O staining, respectively. Real-time quantitative polymerase chain reaction (RT-qPCR) and Western blotting were used to detect the mRNA and protein levels, respectively. Cell proliferation and apoptosis were measured by Cell Counting Kit-8 (CCK-8) assay, colony formation assay and flow cytometry. The interaction of HCP5/musashi RNA-binding protein 2 (MSI2) and oestrogen receptor alpha 1 (ESR1) mRNA was analysed using RNA pulldown and RIP assays. HucMSCs and exosomes were successfully isolated and identified. HucMSC-derived exosomes promoted the proliferation of OGCs and ESR1 expression and inhibited cell apoptosis. HCP5 overexpression in exosomes further enhanced these effects. MSI2 knockdown led to the opposite results. HCP5 targeted MSI2, and MSI2 knockdown reduced the decreases in HCP5 and ESR1 expression. Mechanistically, HCP5 in HucMSC-derived exosomes promoted ESR1 expression by binding to MSI2, which promoted the proliferation of OGCs.

Construction of long non-coding RNA- and microRNA-mediated competing endogenous RNA networks in alcohol-related esophageal cancer

The current study aimed to explore the lncRNA–miRNA–mRNA networks associated with alcohol-related esophageal cancer (EC). RNA-sequencing and clinical data were downloaded from The Cancer Genome Atlas and the differentially expressed genes (DEGs), long non-coding RNAs (lncRNAs, DELs), and miRNAs (DEMs) in patients with alcohol-related and non-alcohol-related EC were identified. Prognostic RNAs were identified by performing Kaplan–Meier survival analyses. Weighted gene co-expression network analysis was employed to build the gene modules. The lncRNA–miRNA–mRNA competing endogenous RNA (ceRNA) networks were constructed based on our in silico analyses using data from miRcode, starBase, and miRTarBase databases. Functional enrichment analysis was performed for the genes in the identified ceRNA networks. A total of 906 DEGs, 40 DELs, and 52 DEMs were identified. There were eight lncRNAs and miRNAs each, including ST7-AS2 and miR-1269, which were significantly associated with the survival rate of patients with EC. Of the seven gene modules, the blue and turquoise modules were closely related to disease progression; the genes in this module were selected to construct the ceRNA networks. SNHG12–miR-1–ST6GAL1, SNHG3–miR-1–ST6GAL1, SPAG5-AS1–miR-133a–ST6GAL1, and SNHG12–hsa-miR-33a–ST6GA interactions, associated with the N-glycan biosynthesis pathway, may have key roles in alcohol-related EC. Thus, the identified biomarkers provide a novel insight into the molecular mechanism of alcohol-related EC.

Non-coding RNA in alcohol use disorder by affecting synaptic plasticity

Alcohol use disorder (AUD) is one of the most serious public health problems worldwide. AUD is a complex disorder, and there is ample evidence that genetic predisposition is critical to its development. Recent studies have shown that genetic predisposition leads to the onset of AUD, and alcohol metabolism can affect epigenetic inheritance, which in turn affects synaptic plasticity, alters brain function, and leads to more severe addictive behaviors. Non-coding RNAs (ncRNAs), especially microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), play an important role in alcohol addiction. This paper reviews the regulatory role of ncRNAs. ncRNAs are involved in enzyme and neurotransmitter reaction systems during alcohol use disorder. Alcohol consumption regulates the expression of ncRNAs that mediate epigenetic modification and synaptic plasticity, which play an important role in the development of chronic AUD. ncRNAs may be used not only as predictors of therapeutic responses but also as therapeutic targets of AUD. Chronic alcoholism is more likely to lead to neuroimmune disorders, including permanent brain dysfunction. AUD induced by long-term alcoholism greatly alters the expression of genes in the human genome, especially the expression of ncRNAs. Alcohol can cause a series of pathological changes by interfering with gene expression, such as through disordered miRNA-mRNA expression networks, epigenetic modifications, disordered metabolism, and even synaptic remodeling. ncRNAs are involved in the transition from moderate drinking to alcohol dependence.

MiR-141-3p overexpression suppresses the malignancy of osteosarcoma by targeting FUS to degrade LDHB

Osteosarcoma (OS) is a common malignant bone cancer. Lactate dehydrogenase B (LDHB) has been revealed to act as a tumor promoter in several cancers. It is also revealed to be correlated with poor prognosis in OS, but its molecular mechanism in OS remains veiled. Our work illustrated that LDHB was overexpressed in OS tissues and cells, and it could enhance cell proliferation, migration, and invasion in OS. Subsequently, it was confirmed that fused in sarcoma (FUS) could bind with LDHB to positively regulate the stability of LDHB messenger RNA (mRNA). Besides, FUS expression was revealed to be elevated in OS tissues and positively correlate with LDHB expression. Furthermore, miR-141-3p, down-regulated in OS cells, was identified as the upstream regulator of FUS in OS cells. Besides, miR-141-3p overexpression decreased mRNA and protein levels of FUS and LDHB. More importantly, overexpression of miR-141-3p could impair FUS overexpression-mediated promotion on LDHB mRNA stability and expression. Finally, rescue assays indicated that miR-141-3p regulated OS cells cellular process via regulating LDHB. In sum, miR-141-3p targets FUS to degrade LDHB, thereby attenuating the malignancy of OS cells.

Suppression of Musashi‑2 by the small compound largazole exerts inhibitory effects on malignant cells

RNA‑binding protein Musashi‑2 (MSI2) serves as a regulator of numerous pivotal biological processes associated with cancer initiation, development and resistance to treatment, and may represent a promising drug target. However, whether MSI2 inhibition is of value in antitumor treatment remains to be determined. The present study demonstrated that MSI2 was upregulated in non‑small cell lung cancer (NSCLC) and was inversely associated with the clinical outcome of the patients. Molecular docking analysis demonstrated that the small compound largazole binds to and may be a potential inhibitor of MSI2. Largazole markedly decreased the protein and mRNA levels of MSI2 and suppressed its downstream mammalian target of rapamycin signaling pathway. Largazole also inhibited the proliferation and induced apoptosis of NSCLC and chronic myeloid leukemia (CML) cells (including bone marrow mononuclear cells harvested from CML patients). These results indicate that MSI2 is an emerging therapeutic target for NSCLC and CML, and the MSI2 inhibitor largazole may hold promise as a treatment for these malignancies.

An RNA-binding-protein, NONO governs energy metabolism by regulating NAMPT in lung cancer

The RNA binding proteins (RBPs) have multiple roles in human cancer. However, their molecular target and function have not been clearly identified. Our genomic analysis derived from patients reveals that NONO is a potential oncogenic gene in lung cancer. NONO is highly expressed in lung cancer tissues compared with normal tissues, and its expression has been correlated with the prognosis of lung cancer patients. We found that NONO significantly influences cancer cell proliferation in lung cancer. Gene expression profiles with NONO-depleted cells revealed that the sirtuin signaling pathway is highly correlated with NONO. Thus, NONO-silenced cells caused reduction of the TCA cycle and glycolysis metabolism. We identified that NONO regulated NAMPT, which is a well-known gene involved in sirtuin signaling, and NONO has a significant correlation with NAMPT in lung cancer patients. We propose that NONO modulates energy metabolism by direct interaction with NAMPT and suggest that a functional relationship between NONO and NAMPT contributes to lung cancer cell survival. Targeting the axis can be a promising approach for patient treatment in lung cancer.

Copy number variations of MTHFSD gene across pig breeds and its association with litter size traits in Chinese indigenous Xiang pig

Copy number variation (CNV) is a major proportion of genetic variation, which changes the gene structure and dosage and affects gene expression and function. To validate the presence and the function of CNV in pig, we used real-time quantitative polymerase chain reaction (qPCR) method to validate a 496 kb CNV region comprising MTHFSD gene on chromosome 6 of Xiang pig detected by single nucleotide polymorphism (SNP) array. Then we investigated the distribution of the MTHFSD CNV in a total of 545 pigs in four breeds. About 46.2% and 32.7% individuals in the four pig breeds were detected to be types of loss and gain of MTHFSD locus. The relative copy numbers of MTHFSD gene showed the largest variation range (0-55 copies) in the Xiang pig population. The copy numbers of MTHFSD gene presented the positive correlations with the transcript level of MTHFSD gene in adult ovaries. Statistical analysis indicated that CNVs of MTHFSD gene was significantly changed the litter size traits of Xiang pigs, and the individuals with CNV gain showed more litter size than the CNV loss pigs. We have reasons to believe that the MTHFSD as RNA-binding protein play an important role in pig reproduction as a result of regulating MTHFS mRNA metabolism.

Musashi RNA-binding protein 2 regulates estrogen receptor 1 function in breast cancer

Musashi RNA-binding protein 2 (MSI2) has important roles in human cancer. However, the regulatory mechanisms by which MSI2 alters breast cancer pathophysiology have not been clearly identified. Here we demonstrate that MSI2 directly regulates estrogen receptor 1 (ESR1), which is a well-known therapeutic target and has been shown to reflect clinical outcomes in breast cancer. Based on gene expression data analysis, we found that MSI2 expression was highly enriched in estrogen receptor (ER)-positive breast cancer and that MSI2 expression was significantly correlated with ESR1 expression, including expression of ESR1 downstream target genes. In addition, MSI2 levels were associated with clinical outcomes. MSI2 influenced breast cancer cell growth by altering ESR1 function. MSI2 alters ESR1 by binding specific sites in ESR1 RNA and by increasing ESR1 protein stability. Taken together, our findings identified a novel regulatory mechanism of MSI2 as an upstream regulator of ESR1 and revealed the clinical relevance of the RNA-binding protein MSI2 in breast cancer.

Multi-Organ Alcohol-Related Damage: Mechanisms and Treatment

Alcohol consumption causes damage to various organs and systems.[...].