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Fragility fracture is a common and serious complication of osteoporosis. Abnormal expression of long non-coding RNAs is closely related to orthopedic diseases and bone metabolism. In the study, the role of lncRNA PVT1 during fracture healing, and the potential mechanism were explained. In the present study, 80 cases with fragility fracture were collected, serum samples were also collected at 7, 14, 21 days after standardized fixation therapy. qRT-PCR was applied for the measurement of mRNA levels. hFOB1.19 cells were recruited for the cell experiments, and the cell viability and apoptosis were detected. Luciferase reporter gene assay was performed for target gene confirmation. It was found that the level of PVT1 increased gradually, while miR-497-5p showed a downward trend over time in both intra-articular and hand fracture patients, and the changes reached a significant level at 21 day after treatment. In vitro experiments demonstrated that PVT1 knockdown promoted cell proliferation and inhibited cell apoptosis in HFOB1.19 cells. LncRNA PVT1 acts as a competing endogenous RNA (ceRNA) of miR-497-5p, and the influence of PVT1 knockdown on HFOB1.19 cell proliferation and apoptosis was reversed by miR-497-5p inhibition. HMGA2 is the target gene of miR-497-5p. It was concluded that LncRNA PVT1 silencing may enhance fracture healing via mediating miR-497-5p/HMGA2 axis.

Malignant glioma, the most common intracranial primary tumor, is characterized by increased angiogenesis. Accumulating evidence has shown that long non-coding RNAs (lncRNAs) play an important role in a variety of biological behaviors of tumors. However, the role of lncRNAs in the regulation of glioma vascular endothelial cell function remains to be investigated. To simulate the glioma microenvironment, we applied glioma conditioned medium (GCM) to human cerebral microvascular endothelial cells (hCMECs). In the present study, the lncRNA SNHG15 was found to be highly expressed in glioma vascular endothelial cells. Cell Counting Kit-8 (CCK-8), migration and tube formation assays demonstrated that knockdown of SNHG15 inhibited glioma vascular endothelial cell proliferation, migration and tube formation in vitro. Furthermore, knockdown of SNHG15 downregulated the expression of VEGFA and Cdc42, which are known to promote angiogenesis. Bioinformatics software and dual-luciferase system analysis confirmed that SNHG15 affected endothelial cell function by targeting miR-153. Additionally, the present study showed that miR-153 targeted the 3'‑untranslated region of VEGFA and Cdc42 and downregulated their expression. In conclusion, knockdown of SNHG15 downregulated the expression of VEGFA and Cdc42 by targeting miR-153, consequently suppressing glioma vascular endothelial cell proliferation, migration and tube formation. Therefore, SNHG15 and miR-153 are new potential therapeutic targets for anti-angiogenesis treatment of glioma.

Glioblastoma is the most common type of malignant primary brain tumor and has high recurrence and lethality rates. Glioblastoma stem cells (GSCs), a subpopulation of glioblastoma cells, may promote rapid tumor recurrence and therapy resistance. Because altered microRNA (miR) expression in GSCs may lead to glioblastoma progression, we assessed the effects of miR-29a expression on the oncogenic behavior of GSCs. MiR-29a expression was lower in GSCs than non-GSCs, and overexpression of miR-29a in GSCs inhibited cell proliferation, migration and invasion, but promoted apoptosis. MiR-29a directly inhibited the expression of Quaking gene isoform 6 (QKI-6) by binding to its 3'-UTR, and thus inhibited GSC malignant behavior. In addition, Wilms' tumor 1-associating protein (WTAP) was identified as a downstream target of QKI-6. Overexpression of miR-29a in GSCs inhibited expression of WTAP and suppressed both phosphoinositide 3-kinase/AKT and extracellular signal-related kinase pathways by downregulating QKI-6, thereby inhibiting cell proliferation, migration, and invasion but promoting apoptosis. We have characterized a novel miR-29a/QKI-6/WTAP axis in GSCs, which may provide theoretical support for the treatment of glioblastoma with miR-29a agomirs.

The blood-tumor barrier (BTB) forms a major obstacle in brain tumor therapy by preventing the delivery of sufficient quantities of therapeutic drugs. Long non-coding RNAs (lncRNAs) play important roles in both normal development and diseases including cancer. Here, we elucidated the expression of lncRNA metastasis associated lung adenocarcinoma transcript 1 (MALAT1) and defined its functional role in the regulation of BTB function as well as its possible molecular mechanisms. Our results proved that MALAT1 expression was up-regulated in brain microvessels of human glioma and glioma endothelial cells (GECs) which were obtained by co-culturing endothelial cells with glioma cells. Functionally, knockdown of MALAT1 resulted in an impairment and increased the permeability of BTB as well as decreased the expression of ZO-1, occludin and claudin-5 in GECs. Further, there was reciprocal repression between MALAT1 and miR-140, and miR-140 mediated the effects that MALAT1 knockdown exerted. Mechanistic investigations defined that nuclear factor YA (NFYA), a CCAAT box-binding transcription factor, was a direct and functional downstream target of miR-140, which was involved in the MALAT1 knockdown induced regulation of BTB function. Furthermore, NFYA could up-regulate the promoter activities and bind to the promoters of ZO-1, occludin and claudin-5 in GECs. Taken together, we have demonstrated the fact that knockdown of MALAT1 resulted in the increased permeability of BTB, which might contribute to establishing potential therapeutic strategies for human gliomas., (Copyright © 2015 Elsevier B.V. All rights reserved.)

Blood-tumor barrier (BTB) limits the delivery of chemotherapeutic agent to brain tumor tissues. Long non-coding RNAs (lncRNAs) have been shown to play critical regulatory roles in various biologic processes of tumors. However, the role of lncRNAs in BTB permeability is unclear. LncRNA TUG1 (taurine upregulated gene 1) was highly expressed in glioma vascular endothelial cells from glioma tissues. It also upregulated in glioma co-cultured endothelial cells (GEC) from BTB model in vitro. Knockdown of TUG1 increased BTB permeability, and meanwhile down-regulated the expression of the tight junction proteins ZO-1, occludin, and claudin-5. Both bioinformatics and luciferase reporter assays demonstrated that TUG1 influenced BTB permeability via binding to miR-144. Furthermore, Knockdown of TUG1 also down-regulated Heat shock transcription factor 2 (HSF2), a transcription factor of the heat shock transcription factor family, which was defined as a direct and functional downstream target of miR-144. HSF2 up-regulated the promoter activities and interacted with the promoters of ZO-1, occludin, and claudin-5 in GECs. In conclusion, our results indicate that knockdown of TUG1 increased BTB permeability via binding to miR-144 and then reducing EC tight junction protein expression by targeting HSF2. Thus, TUG1 may represent a useful future therapeutic target for enhancing BTB permeability.

Glioblastoma (GBM) is the most common and aggressive primary brain tumor. Great interest persists in useful therapeutic targets in GBM. Aberrant expression of long non-coding RNAs (lncRNAs) has been functionally associated with many cancers. Here, we elucidated the function and the possible molecular mechanisms of lncRNA XIST in human glioblastoma stem cells (GSCs). Our results proved that XIST expression was up-regulated in glioma tissues and GSCs. Functionally, knockdown of XIST exerted tumor-suppressive functions by reducing cell proliferation, migration and invasion as well as inducing apoptosis. The in vivo studies also showed that knockdown of XIST suppressed tumor growth and produced high survival in nude mice. Further, there was reciprocal repression between XIST and miR-152. Mechanistic investigations defined the direct binding ability of the predicted miR-152 binding site on the XIST. In addition, XIST and miR-152 are probably in the same RNA induced silencing complex (RISC). Finally, miR-152 mediated the tumor-suppressive effects that knockdown of XIST exerted. Taken together, these results provided a comprehensive analysis of XIST in GSCs and important clues for understanding the key roles of lncRNA-miRNA functional network in human glioma., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Glioblastoma (GBM) is one of the most common and aggressive primary brain tumors in adults. Deregulated expression of microRNAs (miRNAs) has been associated with GBM progression through alterations in either oncogenic or tumor suppressor targets. Here, we elucidated the function and the possible molecular mechanisms of miR-449a in human GBM cell lines and tumor specimens-derived glioblastoma stem cells (GSCs). Quantitative real-time PCR demonstrated that miR-449a was down-regulated in human GBM cell lines and GSCs. Functionally, miR-449a acted as a tumor suppressor by reducing cell proliferation, migration and invasion as well as inducing apoptosis in human GBM cell lines and GSCs. Myc-associated zinc-finger protein (MAZ) was identified as a direct target of miR-449a, mediating these tumor-suppressive effects, demonstrated by Western blot assay and luciferase assays. Moreover, over-expression of miR-449a inhibited the expression of Podoplanin (PDPN) by down-regulating MAZ which could positively control the promoter activities via binding to the promoter of PDPN, demonstrated by luciferase assays and chromatin immunoprecipitation assays. Further, the PI3K/AKT pathway was blocked when MAZ was down-regulated by miR-449a. This process was coincided with the up-regulation of apoptotic proteins and the down-regulation of anti-apoptotic proteins, MMP2 and MMP9. Furthermore, nude mice carrying over-expressed miR-449a combined with knockdown MAZ tumors produced the smallest tumors and the highest survival. These results elucidated a novel molecular mechanism of GBM progression, and may thus suggest a promising application for GBM treatment., (Copyright © 2014 Federation of European Biochemical Societies. Published by Elsevier B.V. All rights reserved.)

Glioblastoma (GBM) is the most common central nervous system tumor and the molecular mechanism driving its development is still largely unknown, limiting the treatment of this disease. In the present study, we explored the potential role of miR-152 in glioblastoma stem cells (GSCs) as well as the possible molecular mechanisms. Our results proved that miR-152 was down-regulated in human GSCs. Restoring the expression of miR-152 dramatically reduced the cell proliferation, cell migration and invasion as well as inducing apoptosis. Mechanistic investigations defined Krüppel-like factor 4 (KLF4) as a direct and functional downstream target of miR-152, which was involved in the miR-152-mediated tumor-suppressive effects in GSCs. Meanwhile, this process was coincided with the down-regulated LGALS3 that could be bound and promoted by KLF4, leading to attenuate the activation of MEK1/2 and PI3K signal pathways. Moreover, the in vivo study showed that miR-152 over-expression and KLF4 knockdown produced the smallest tumor volume and the longest survival in nude mice. Taken together, these results elucidated the function of miR-152 in GSCs progression and suggested a promising application of it in glioma treatment., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Blood-tumor barrier (BTB) constitutes an efficient organization of tight junctions that impairs the delivery of therapeutic drugs. However, the methods and molecular mechanisms underlying the BTB opening remain elusive. MicroRNAs (miRNAs) have recently emerged as key regulators of various biologic processes and therapeutic targets. In this study, we have identified microRNA-181a (miR-181a) as a critical miRNA in opening BTB. MicroRNA-181a expression was upregulated in glioma endothelial cells (GECs), which were obtained by coculturing endothelial cells (ECs) with glioma cells. Overexpression of miR-181a resulted in an impaired and permeability increased BTB, and meanwhile reduced the expression of zonula occluden (ZO)-1, occludin, and claudin-5. Kruppel-like factor 6 (KLF6), a transcription factor of the zinc-finger family, was downregulated in GECs. Mechanistic investigations defined it as a direct and functional downstream target of miR-181a, which was involved in the regulation of BTB permeability and the expression of ZO-1, occludin, and claudin-5. Furthermore, luciferase assays and chromatin immunoprecipitation assays showed that KLF6 upregulated the promoter activities and interacted with the promoters of ZO-1, occludin, and claudin-5 in GECs. Collectively, we showed the possibility that overexpression of miR-181a contributes to the increased permeability of BTB by targeting KLF6, thereby revealing potential therapeutic targets for the treatment of brain gliomas.

Prostate cancer (PCa) is the most common solid tumor malignancy in men that severely influences quality of life. Surgery is most often the recommended treatment for PCa, but radical prostatectomy can cause significant urinary adverse effects. Therefore, finding effective biochemical treatments for PCa remains a necessity. Aurora kinase A has been shown to be involved in PCa progression, thus making it a good target for PCa therapy. miRNAs are important regulators of gene expression, with some miRNAs specifically involved in carcinogenesis. Therefore, herein, we identified miRNAs targeted to aurora kinase A and examined their effects on the growth of PCa. We used primary samples from PCa patients and PCa cell lines as research subjects. We demonstrate that miR-199a-3p is down-regulated in PCa tissues compared with normal prostate tissues, with the expression pattern inversely correlated with the expression pattern of aurora kinase A. We find that miR-199a-3p agomir inhibits aurora kinase A and attenuates xenograft tumor growth of PCa. Moreover, we demonstrate that down-regulation of miR-199a-3p results from enhancement of the methylation of miR-199a gene in PCa. Furthermore, we find that the expression level of miR-199a-3p is inversely correlated to tumor stage and Gleason score of PCa. Revealing novel mechanisms for oncogene inhibition by miRNA-mediated pathways offers new avenues for PCa treatment., (Copyright © 2014 American Society for Investigative Pathology. Published by Elsevier Inc. All rights reserved.)

MicroRNAs are currently considered as an active and rapidly evolving area for the treatment of tumors. In this study, we elucidated the biological significance of miR-330 in glioblastoma stem cells (GSCs) as well as the possible molecular mechanisms. SH3GL2 is mainly distributed in the central nervous system and considered to be a tumor suppressor in many tumors. In the present study, we identified miR-330 as a potential regulator of SH3GL2 and we found that it was to be inversely correlated with SH3GL2 expression in GSCs which were isolated from U87 cell lines. The expression of miR-330 enhanced cellular proliferation, promoted cell migration and invasion, and dampened cell apoptosis. When the GSCs were co-transfected with the plasmid containing short hairpin RNA directed against human SH3GL2 gene and miR-330 mimic, we found that miR-330 promoted the malignant behavior of GSCs by down-regulating the expression of SH3GL2. Meanwhile, the ERK and PI3K/AKT signaling pathways were significantly activated, leading to the decreased expression of apoptotic protein and increased expression of anti-apoptotic protein. Furthermore, in orthotopic mouse xenografts, the mice given stable over-expressed SH3GL2 cells co-transfected with miR-330 knockdown plasmid had the smallest tumor sizes and longest survival. In conclusion, these results suggested that miR-330 negatively regulated the expression of SH3GL2 in GSCs, which promoted the oncogenic progression of GSCs through activating ERK and PI3K/AKT signaling pathways. The elucidation of these mechanisms will provide potential therapeutic approaches for human glioblastoma.