The long noncoding RNA FTX promotes a malignant phenotype in bone marrow mesenchymal stem cells via the miR-186/c-Met axis

Emerging roles of long non-coding RNA FTX in human disorders

Long non-coding RNAs (lncRNAs) are involved the progression of cancerous and non-cancerous disorders via different mechanism. FTX (five prime to xist) is an evolutionarily conserved lncRNA that is located upstream of XIST and regulates its expression. FTX participates in progression of various malignancy including gastric cancer, glioma, ovarian cancer, pancreatic cancer, and retinoblastoma. Also, FTX can be involved in the pathogenesis of non-cancerous disorders such as endometriosis and stroke. FTX acts as competitive endogenous RNA (ceRNA) and via sponging various miRNAs, including miR-186, miR-200a-3p, miR-215-3p, and miR-153-3p to regulate the expression of their downstream target. FTX by targeting various signaling pathways including Wnt/β-catenin, PI3K/Akt, SOX4, PDK1/PKB/GSK-3β, TGF-β1, FOXA2, and PPARγ regulate molecular mechanism involved in various disorders. Dysregulation of FTX is associated with an increased risk of various disorders. Therefore, FTX and its downstream targets may be suitable biomarkers for the diagnosis and treatment of human malignancies. In this review, we summarized the emerging roles of FTX in human cancerous and non-cancerous cells.

RNA-binding protein DHX9 promotes glioma growth and tumor-associated macrophages infiltration via TCF12

BACKGROUND

Glioma is the most common malignant tumor of the central nervous system, with high heterogeneity, strong invasiveness, high therapeutic resistance, and poor prognosis, comprehending a serious challenge in neuro-oncology. Until now, the mechanisms underlying glioma progression have not been fully elucidated.

METHODS

The expression of DExH-box helicase 9 (DHX9) in tissues and cells was detected by qRT-PCR and western blot. EdU and transwell assays were conducted to assess the effect of DHX9 on proliferation, migration and invasion of glioma cells. Cocultured model was used to evaluate the role of DHX9 on macrophages recruitment and polarization. Animal study was performed to explore the role of DHX9 on macrophages recruitment and polarization in vivo. Bioinformatics analysis, dual-luciferase reporter assay and chromatin immunoprecipitation (ChIP)-qPCR assay was used to explore the relation between DHX9 and TCF12/CSF1.

RESULTS

DHX9 was elevated in gliomas, especially in glioblastoma multiforme (GBM). Besides promoting the proliferation, migration, and invasion of glioma cells, DHX9 facilitated the infiltration of macrophages into glioma tissues and polarization to M2-like macrophages, known as tumor-associated macrophages (TAMs). DHX9 silencing decreased the expression of colony-stimulating factor 1 (CSF1), which partially restored the inhibitory effect on malignant progress of glioma and infiltration of TAMs caused by DHX9 knockdown by targeting the transcription factor 12 (TCF12). Moreover, TCF12 could directly bind to the promoter region of CSF1.

CONCLUSION

DHX9/TCF12/CSF1 axis regulated the increases in the infiltration of TAMs to promote glioma progression and might be a novel potential target for future immune therapies against gliomas.

microRNA-265 Regulates Bone Marrow Mesenchymal Stem Cells Differentiation and Promotes Sepsis Lung Injury Repair via Transforming Growth Factor Beta 1

Our study investigates whether miR-265 regulates the differentiation of rat bone marrow mesenchymal stem cells (BMSCs) into alveolar type II epithelial cells (ATII) through TGF-β1 and promotes lung injury repair in rats with sepsis, thereby inhibiting sepsis progression. 25 patients with sepsis admitted to the Respiratory and Critical Care Medicine Department of the hospital and 17 normal controls were included. TGF-β1 level was measured by ELISA. miR-265 level was measured by qRT-PCR and AT II-related genes and proteins expression was analyzed by western blot and qRT-PCR. miR-265 expression was significantly higher in sepsis patients than normal group. Progenitor BMSCs were long and shuttle-shaped after 1 and 3 days of growth. Cultured MSCs had low expression of the negative antigen CD34 (4.32%) and high expression of the positive antigen CD44 (99.87%). TGF-β1 level was significantly increased with longer induction time, while miR-265 expression was significantly decreased in cell culture medium. miR-265 interference significantly decreased TGF-β1 expression. In conclusion, miR-265 inhibits BMSC differentiation to AT II via regulation of TGF-β1, thereby inhibiting sepsis progression.

The lncRNAs at X Chromosome Inactivation Center: Not Just a Matter of Sex Dosage Compensation

Non-coding RNAs (ncRNAs) constitute the majority of the transcriptome, as the result of pervasive transcription of the mammalian genome. Different RNA species, such as lncRNAs, miRNAs, circRNA, mRNAs, engage in regulatory networks based on their reciprocal interactions, often in a competitive manner, in a way denominated “competing endogenous RNA (ceRNA) networks” (“ceRNET”): miRNAs and other ncRNAs modulate each other, since miRNAs can regulate the expression of lncRNAs, which in turn regulate miRNAs, titrating their availability and thus competing with the binding to other RNA targets. The unbalancing of any network component can derail the entire regulatory circuit acting as a driving force for human diseases, thus assigning “new” functions to “old” molecules. This is the case of XIST, the lncRNA characterized in the early 1990s and well known as the essential molecule for X chromosome inactivation in mammalian females, thus preventing an imbalance of X-linked gene expression between females and males. Currently, literature concerning XIST biology is becoming dominated by miRNA associations and they are also gaining prominence for other lncRNAs produced by the X-inactivation center. This review discusses the available literature to explore possible novel functions related to ceRNA activity of lncRNAs produced by the X-inactivation center, beyond their role in dosage compensation, with prospective implications for emerging gender-biased functions and pathological mechanisms.

Non-Coding RNAs in Glioma Microenvironment and Angiogenesis

Glioma, especially glioblastoma, is the most common and lethal brain tumor. In line with the complicated vascularization processes and the strong intratumoral heterogeneity, tumor-associated blood vessels in glioma are regulated by multiple types of cells through a variety of molecular mechanisms. Components of the tumor microenvironment, including tumor cells and tumor-associated stromata, produce various types of molecular mediators to regulate glioma angiogenesis. As critical regulatory molecules, non-coding RNAs (ncRNAs) inside cells or secreted to the tumor microenvironment play essential roles in glioma angiogenesis. In this review, we briefly summarize recent studies about the production, delivery, and functions of ncRNAs in the tumor microenvironment, as well as the molecular mechanisms underlying the regulation of angiogenesis by ncRNAs. We also discuss the ncRNA-based therapeutic strategies in the anti-angiogenic therapy for glioma treatment.

Long noncoding RNA DLGAP1-AS1 promotes the progression of glioma by regulating the miR-1297/EZH2 axis

Dysregulated lncRNAs have been implicated in a plethora of tumors, including glioma. One such oncogenic lncRNAs that has been reported in several cancers is the lncRNA DLGAP1 antisense RNA 1 (DLGAP1-AS1). This study seeks to characterize the expression of DLGAP1-AS1 in glioma tissues, which we found to be raised in both glioma samples and cell lines. Functional experiments revealed that DLGAP1-AS1 promoted in vitro glioma cell invasion, migration and proliferation. DLGAP1-AS1 was found to function as a miR-1297 sponge, based on information from luciferase reporter assays, RNA pull-down assays and publicly available online databases. miR-1297 was in turn found to functionally target EZH2. DLGAP1-AS1 modulated EZH2 expressions through miR-1297 sponging. Glioma progression appears to be supported DLGAP1-AS1 -promoted activation of the miR-1297/EZH2 axis. The components of this axis may function as therapeutic targets for glioma.