RBM47 is a Critical Regulator of Mouse Embryonic Stem Cell Differentiation.

RNA-binding proteins (RBPs) are pivotal for regulating gene expression as they are involved in each step of RNA metabolism. Several RBPs are essential for viable growth and development in mammals. RNA-binding motif 47 (RBM47) is an RRM-containing RBP whose role in mammalian embryonic development is poorly understood yet deemed to be essential since its loss in mouse embryos leads to perinatal lethality. In this study, we attempted to elucidate the significance of RBM47 in cell-fate decisions of mouse embryonic stem cells (mESCs). Downregulation of Rbm47 did not affect mESC maintenance and the cell cycle but perturbed the expression of primitive endoderm (PrE) markers and increased GATA4 + PrE-like cells. However, the PrE misregulation could be reversed by either overexpressing Rbm47 or treating the knockdown mESCs with the inhibitors of FGFR or MEK, suggesting an implication of RBM47 in regulating FGF-ERK signaling. Rbm47 knockdown affected the multi-lineage differentiation potential of mESCs as it regressed teratoma in NSG mice and led to a skewed expression of differentiation markers in serum-induced monolayer differentiation. Further, lineage-specific differentiation revealed that Rbm47 is essential for proper differentiation of mESCs towards neuroectodermal and endodermal fate. Taken together, we assign a hitherto unknown role(s) to RBM47 in a subtle regulation of mESC differentiation.

NSG-70, a new glioblastoma cell line with mixed proneural-mesenchymal features, associates NOTCH1-WNT5A signaling with stem cell maintenance and angiogenesis.

BACKGROUND: Glioblastoma initiation and progression is believed to be driven by Glioma stem cells (GSCs). Activation of NOTCH1 and WNT, and more recently, non-canonical WNT5A signaling, has been demonstrated to regulate self-renewal and differentiation of the GSCs crucially. High expression levels of NOTCH1 and WNT in GBM tumors contribute to the sustenance of GSCs and mediate characteristic phenotypic plasticity, which is reflected by the different subtypes and tremendous intra-tumor heterogeneity. However, the coregulation of NOTCH1 and WNT5A is not well understood. Here, we studied the role of these molecules in regulating the characteristics of different GSC subtypes. METHODS: We established a novel GSC-enriched cell model, referred to as NSG-70, from a patient with recurrent GBM. NSG-70 cells harbor a unique cytogenetic feature, viz. isochromosome 9q. At the same time, its expression profiles indicate that it is a mixed lineage comprising proneural and mesenchymal subtypes. We examined the relevance of NOTCH1 and WNT5A signaling and their coordinated action in GBM using these cells and other patient-derived models representing different GSC subtypes. RESULTS: Our data revealed that the downregulation of NOTCH1 resulted in the suppression of stem cell and mesenchymal markers and significantly reduced the levels of WNT5A. NOTCH1 knockdown also led to a notable reduction in the vasculogenic mimicry of GSCs. Interestingly, knockdown of WNT5A exhibited similar effects and drove quiescent GSC towards proliferation. In a complementary manner, ectopic expression of WNT5A or rhWNT5A treatment rescued the effects of NOTCH1 knockdown. CONCLUSION: The resistance of GSCs towards conventional therapies in part due to subtype interconversion demands therapies targeting specific GSC subtype. Our study suggests the need for a combinatorial approach that could effectively target the NOTCH1-WNT5A signaling axis toward eliminating GSCs.

RNA binding motif 47 (RBM47): emerging roles in vertebrate development, RNA editing and cancer.

RNA-binding proteins (RBPs) are critical players in the post-transcriptional regulation of gene expression and are associated with each event in RNA metabolism. The term 'RNA-binding motif' (RBM) is assigned to novel RBPs with one or more RNA recognition motif (RRM) domains that are mainly involved in the nuclear processing of RNAs. RBM47 is a novel RBP conserved in vertebrates with three RRM domains whose contributions to various aspects of cellular functions are as yet emerging. Loss of RBM47 function affects head morphogenesis in zebrafish embryos and leads to perinatal lethality in mouse embryos, thereby assigning it to be an essential gene in early development of vertebrates. Its function as an essential cofactor for APOBEC1 in C to U RNA editing of several targets through substitution for A1CF in the A1CF-APOBEC1 editosome, established a new paradigm in the field. Recent advances in the understanding of its involvement in cancer progression assigned RBM47 to be a tumor suppressor that acts by inhibiting EMT and Wnt/[Formula: see text]-catenin signaling through post-transcriptional regulation. RBM47 is also required to maintain immune homeostasis, which adds another facet to its regulatory role in cellular functions. Here, we review the emerging roles of RBM47 in various biological contexts and discuss the current gaps in our knowledge alongside future perspectives for the field.

Extrachromosomal DNA: Redefining the pathogenesis of glioblastoma.

Glioblastoma is an incurable most prevalent primary malignant brain tumor in adults. Surgery followed by radiotherapy with concomitant chemotherapy is the standard of care in patients with glioblastoma. Although, prognosis remains poor with a median survival in the range of 12-15 months. Over the decades of research has identified the gene mutation, angiogenesis, cell signaling for the development novel therapeutics. However, recent understanding on extrachromosomal DNA (ecDNA) put extra-layer of complexity in glioblastoma pathogenesis. These ecDNAs are present in significantly higher copy number in the nucleus of the cancer cells and contains several oncogenes which are instrumental for intra-tumoral genetic heterogeneity, accelerated tumor evolution and therapy resistance. In this review, we will discuss the current understanding on biogenesis, disease progression and potential therapeutic implications of ecDNAs in glioblastoma.

Establishment of integration free iPSC clones, NCCSi011-A and NCCSi011-B from a liver cirrhosis patient of Indian origin with hepatic encephalopathy.

Liver cirrhosis accompanied with hepatic encephalopathy commonly causes cognitive impairment in patients. To model this disease, two independent patient specific induced pluripotent stem cell-line (iPSC) clones, NCCSi011-A and NCCSi011-B were generated by reprogramming the CD4+ T cells of an Indian male patient suffering from this chronic condition. Both clones expressed the stemness markers, formed embryoid bodies (EBs) with potential for spontaneous differentiation in to all the three lineages, exhibited normal karyotype (46, XY) and demonstrated alkaline phosphatase activity. These generated iPSC lines have potential for use in understanding biology of the disease and evaluation of drugs.

Development and characterization of two independent integration free iPSC clones NCCSi010-A and NCCSi010-B from a patient with alcoholic liver cirrhosis of Indian ethnicity.

We generated two human induced pluripotent stem cell-line (iPSC) clones, NCCSi010-A and NCCSi010-B, from a 32-year-old alcoholic cirrhosis patient with minimal hepatic encephalopathy of Indian origin by reprogramming his CD4+ T cells with integration free Sendai viral vector system. The generated iPSC clones showed high alkaline phosphatase activity, expressed pluripotency markers, possessed potential for multi-lineage differentiation and exhibited a normal karyotype (46, XY). These two-patient specific iPSC clones of alcoholic liver cirrhosis can potentially serve as models for disease modeling, drug development and organoid generation (Shah and Bataller, 2016).

Generation of two control iPSC clones NCCSi008-A and NCCSi008-B from an individual of Indian ethnicity.

Two iPSC clones, NCCSi008-A and NCCSi008-B, were generated from a healthy male individual of Indian origin by reprogramming his CD4+ T cells with an integration free Sendai viral vector. The established iPSC clones showed high alkaline phosphatase (ALP) activity, expression of pluripotency markers, a normal male karyotype consistent with the donor gender (46, XY) and has potential for multi-lineage differentiation. These iPSC lines of Indian origin would serve as valuable resources for disease modeling, drug development and screening.

Generation and characterization of three clones (NCCSi007A, NCCSi007B and NCCSi007C) of an integration free induced Pluripotent Stem Cell line from a patient with alcoholic liver cirrhosis of Indian ethnicity.

Three induced pluripotent stem cells (iPSC) clones NCCSi007-A, NCCSi007-B and NCCSi007-C were generated from CD4+T cells of a 38 years old male patient suffering from liver cirrhosis- alcoholic and minimal hepatic encephalopathy of Indian origin. The CD4+T cells of the patient were reprogrammed using integration free, Sendai viral vector system. Each of the three iPSC clones showed high alkaline phosphatase (ALP) activity, expressed pluripotency markers OCT4, SOX2, NANOG, KLF4, SSEA-4, TRA-1-60, showed normal male karyotype (46, XY) and exhibited multi-lineage differentiation.

Generation of two induced pluripotent stem cell lines NCCSi005A and NCCSi006A from CD4+T cells of healthy individuals of Indian origin.

Human induced pluripotent stem cell-lines (iPSCs) of Indian origin NCCSi005A and NCCSi006A were established by reprogramming of CD4+T cells, isolated from the peripheral blood mononuclear cells (PBMCs) of two healthy female donors. Reprogramming was achieved using integration free, Sendai viral vector system expressing cocktail of transcription factors KOS, hc-MYC and hKLF4. Both the established cell-lines showed alkaline phosphatase activity, expressed stemness markers, exhibited normal female karyotype and displayed potential for tri-lineage differentiation. These two CD4+T cells derived cell-lines represent valuable resource as control iPSC cell lines of Indian origin.

Effective Visualization and Easy Tracking of Extracellular Vesicles in Glioma Cells.

Extracellular vesicles (EVs) are nano-sized, membrane-bound structures secreted by cells and play critical roles in mediating intercellular signaling. EVs based on their size as well as mechanisms of biosynthesis are categorized as either microvesicles (200-1000 nm) or exosomes (30-200 nm). The EVs carry several biomolecules like proteins, DNAs, RNAs, and lipids into other cells and modulate several cellular functions. Being of very small sizes, it is very challenging to analyze them using conventional microscopes. Here, we report a new method developed by us for visualizing EVs using simple immune-fluorescence based technique, wherein the isolated EVs can be stained with fluorescently tagged antibodies to proteins present in EVs. The stained EVs can then be analyzed by using either confocal or super-resolution microscopes. Our method detailed here is equally effective in staining proteins that are present inside the EVs as well as those localized to the membranes of vesicles. By employing unique staining strategies, we have minimized the background noise and thereby improved the signal strength in confocal microscope. Using electron microscopy, we have ascertained that the structural integrity of the labeled EVs is intact. More importantly, the labeling of EVs does not affect their functionality and their localization can be tracked after its uptake by recipient cells without resorting to any conventional reporter-based strategies or lipophilic dyes. In conclusion, the method described here is a simple, sensitive and efficient immune-fluorescence based method for visualization of molecules within the EVs.

Attenuation of Tumor Suppressive Function of FBXO16 Ubiquitin Ligase Activates Wnt Signaling In Glioblastoma.

Glioblastoma (GBM) is one of the most aggressive and lethal types of brain tumor. Despite the advancements in conventional or targeted therapies, median survival of GBM patients is less than 12 months. Amongst various signaling pathways aberrantly activated in glioma, active Wnt/ß-catenin signaling pathway is one of the crucial oncogenic players. ß-catenin, an important mediator of Wnt signaling pathway, gets phosphorylated by GSK3ß complex. Phosphorylated ß-catenin is specifically recognized by ß-Trcp1, a F-box/WD40-repeat protein and with the help of Skp1 it plays a central role in recruiting phosphorylated ß-catenin for degradation. In GBM, expression of ß-TrCP1 and its affinity for ß catenin is reported to be very low. Hence, we investigated whether any other members of the E3 ubiquitin ligase family could be involved in degradation of nuclear ß-catenin. We here report that FBXO16, a component of SCF E3 ubiquitin ligase complex, is an interacting protein partner for ß-catenin and mediates its degradation. Next, we show that FBXO16 functions as a tumor suppressor in GBM. Under normal growth conditions, FBXO16 proteasomally degrades ß-catenin in a GSK-3ß independent manner. Specifically, the C-terminal region of FBXO16 targets the nuclear ß-catenin for degradation and inhibits TCF4/LEF1 dependent Wnt signaling pathway. The nuclear fraction of ß-catenin undergoes K-48 linked poly-ubiquitination in presence of FBXO16. In summary, we show that due to low expression of FBXO16, the ß-catenin is not targeted in glioma cells leading to its nuclear accumulation resulting in active Wnt signaling. Activated Wnt signaling potentiates the glioma cells toward a highly proliferative and malignant state.

Noncoding RNA Ginir functions as an oncogene by associating with centrosomal proteins.

Long noncoding RNAs constitute a major fraction of the eukaryotic transcriptome, and together with proteins, they intricately fine-tune various growth regulatory signals to control cellular homeostasis. Here, we describe the functional characterisation of a novel pair of long intergenic noncoding RNAs (lincRNAs) comprised of complementary, fully overlapping sense and antisense transcripts Genomic Instability Inducing RNA (Ginir) and antisense RNA of Ginir (Giniras), respectively, from mouse cells. This transcript pair is expressed in a spatiotemporal manner during embryonic development. The individual levels of the sense and antisense transcripts are finely balanced during embryonic growth and in adult tissues. Functional studies of the individual transcripts performed using overexpression and knock-down strategies in mouse cells has led to the discovery that Ginir RNA is a regulator of cellular proliferation and can act as an oncogene having a preeminent role in malignant transformation. Mechanistically, we demonstrate that the oncogenic function of Ginir is mediated by its interaction with centrosomal protein 112 (Cep112). Additionally, we establish here a specific interaction between Cep112 with breast cancer type 1 susceptibility protein (Brca1), another centrosome-associated protein. Next, we prove that the mutual interaction between Cep112 with Brca1 is significant for mitotic regulation and maintenance of genomic stability. Furthermore, we demonstrate that the Cep112 protein interaction with Brca1 protein is impaired when an elevated level of Ginir RNA is present in the cells, resulting in severe deregulation and abnormality in mitosis, leading to malignant transformation. Inhibiting the Ginir RNA function in transformed cells attenuates transformation and restores genomic stability. Together, these findings unravel, to our knowledge, a hitherto-unknown mechanism of oncogenesis mediated by a long noncoding RNA and establishes a unique role of Cep112-Brca1 interaction being modulated by Ginir RNA in maintaining mitotic fidelity.

Mitochondria Targeting Non-Isocyanate-Based Polyurethane Nanocapsules for Enzyme-Triggered Drug Release.

Surface engineering of nanocarriers allows fine-tuning of their interactions with biological organisms, potentially forming the basis of devices for the monitoring of intracellular events or for intracellular drug delivery. In this context, biodegradable nanocarriers or nanocapsules capable of carrying bioactive molecules or drugs into the mitochondrial matrix could offer new capabilities in treating mitochondrial diseases. Nanocapsules with a polymeric backbone that undergoes programmed rupture in response to a specific chemical or enzymatic stimulus with subsequent release of the bioactive molecule or drug at mitochondria would be particularly attractive for this function. With this goal in mind, we have developed biologically benign nanocapsules using polyurethane-based, polymeric backbone that incorporates repetitive ester functionalities. The resulting nanocapsules are found to be highly stable and monodispersed in size. Importantly, a new non-isocyanate route is adapted for the synthesis of these non-isocyanate polyurethane nanocapsules (NIPU). The embedded ester linkages of these capsules' shells have facilitated complete degradation of the polymeric backbone in response to a stimulus provided by an esterase enzyme. Hydrophilic payloads like rhodamine or doxorubicin can be loaded inside these nanocarriers during their synthesis by an interfacial polymerization reaction. The postgrafting of the nanocapsules with phosphonium ion, a mitochondria-targeting receptor functionality, has helped us achieve the site-specific release of the drug. Co-localization experiments with commercial mitotracker green as well as mitotracker deep red confirmed localization of the cargo in mitochondria. Our in vitro studies confirm that specific release of doxorubicin within mitochondria causes higher cytotoxicity and cell death compared to free doxorubicin. Endogenous enzyme triggered nanocapsule rupture and release of the encapsulated dye is also demonstrated in a zebrafish model. The results of this proof-of-concept study illustrate that NIPU nanocarriers can provide a site-specific delivery vehicle and improve the therapeutic efficacy of a drug or be used to produce organelle-specific imaging studies.

Angiogenic Gene Signature Derived from Subtype Specific Cell Models Segregate Proneural and Mesenchymal Glioblastoma.

Intertumoral molecular heterogeneity in glioblastoma identifies four major subtypes based on expression of molecular markers. Among them, the two clinically interrelated subtypes, proneural and mesenchymal, are the most aggressive with proneural liable for conversion to mesenchymal upon therapy. Using two patient-derived novel primary cell culture models (MTA10 and KW10), we developed a minimal but unique four-gene signature comprising genes vascular endothelial growth factor A (VEGF-A), vascular endothelial growth factor B (VEGF-B) and angiopoietin 1 (ANG1), angiopoietin 2 (ANG2) that effectively segregated the proneural (MTA10) and mesenchymal (KW10) glioblastoma subtypes. The cell culture preclassified as mesenchymal showed elevated expression of genes VEGF-A, VEGF-B and ANG1, ANG2 as compared to the other cell culture model that mimicked the proneural subtype. The differentially expressed genes in these two cell culture models were confirmed by us using TCGA and Verhaak databases and we refer to it as a minimal multigene signature (MMS). We validated this MMS on human glioblastoma tissue sections with the use of immunohistochemistry on preclassified (YKL-40 high or mesenchymal glioblastoma and OLIG2 high or proneural glioblastoma) tumor samples (n = 30). MMS segregated mesenchymal and proneural subtypes with 83% efficiency using a simple histopathology scoring approach (p = 0.008 for ANG2 and p = 0.01 for ANG1). Furthermore, MMS expression negatively correlated with patient survival. Importantly, MMS staining demonstrated spatiotemporal heterogeneity within each subclass, adding further complexity to subtype identification in glioblastoma. In conclusion, we report a novel and simple sequencing-independent histopathology-based biomarker signature comprising genes VEGF-A, VEGF-B and ANG1, ANG2 for subtyping of proneural and mesenchymal glioblastoma.

Extracellular Vesicles As Modulators of Tumor Microenvironment and Disease Progression in Glioma.

Diffuse gliomas are lethal tumors of the central nervous system (CNS) characterized by infiltrative growth, aggressive nature, and therapeutic resistance. The recent 2016 WHO classification for CNS tumors categorizes diffuse glioma into two major types that include IDH wild-type glioblastoma, which is the predominant type and IDH-mutant glioblastoma, which is less common and displays better prognosis. Recent studies suggest presence of a distinct cell population with stem cell features termed as glioma stem cells (GSCs) to be causal in driving tumor growth in glioblastoma. The presence of a stem and progenitor population possibly makes glioblastoma highly heterogeneous. Significantly, tumor growth is driven by interaction of cells residing within the tumor with the surrounding milieu termed as the tumor microenvironment. It comprises of various cell types such as endothelial cells, secreted factors, and the surrounding extracellular matrix, which altogether help perpetuate the proliferation of GSCs. One of the important mediators critical to the cross talk is extracellular vesicles (EVs). These nano-sized vesicles play important roles in intercellular communication by transporting bioactive molecules into the surrounding milieu, thereby altering cellular functions and/or reprogramming recipient cells. With the growing information on the contribution of EVs in modulation of the tumor microenvironment, it is important to determine their role in both supporting as well as promoting tumor growth in glioma. In this review, we provide a comprehensive overview of the role of EVs in tumor progression and glioma pathogenesis.

Backbone Engineered γ-Peptide Amphitropic Gels for Immobilization of Semiconductor Quantum Dots and 2D Cell Culture.

We are reporting a spontaneous supramolecular assembly of backbone engineered γ-peptide scaffold and its utility in the immobilization of semiconductor quantum dots and in cell culture. The stimulating feature of this γ-peptide scaffold is that it efficiently gelates both aqueous phosphate buffers and aromatic organic solvents. A comparative and systematic investigation reveals that the greater spontaneous self-aggregation property of γ-peptide over the α- and ß-peptide analogues is mainly due to the backbone flexibility, increased hydrophobicity, and π-π stacking of γ-phenylalanine residues. The hydrogels and organogels obtained from the γ-peptide scaffold have been characterized through field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), FT-IR, circular dichroism (CD), wide-angle X-ray diffraction, and rheometric study. Additionally, the peptide hydrogel has displayed a stimuli-responsive and thixotropic signature, which leads to the injectable hydrogels. 2D cell culture studies using normal and cancer cell lines reveal the biocompatibility of γ-peptide hydrogels. Further, the immobilization of semiconductor core-shell quantum dots in the transparent γ-peptide organogels showed ordered arrangement of quantum dots along the peptide fibrillar network with retaining photophysical property. Overall, γ-peptide scaffolds may serve as potential templates for the design of new functional biomaterials.

pH sensitive coiled coils: a strategy for enhanced liposomal drug delivery.

Stimuli responsive controlled release from liposome based vesicles is a promising strategy for the site specific delivery of drugs. Herein, we report the design of pH sensitive coiled coils and their incorporation into the liposome as triggers for the controlled release of encapsulated drugs. The designed coiled coil peptides with the incorporation of environment sensitive fluorescent amino acids were found to be stable at physiological pH and unstructured while changing the pH of the environment to either acidic or basic. This pH dependent conformational switch of the coiled-coil polypeptides was exploited as triggers for the enhanced release of the encapsulated drug molecules from liposomes. The SEM, DLS and TEM analysis revealed the uniform morphology of the peptide liposome hybrid vesicles. Further, the drug encapsulated liposome internalization experiments with cancer cells revealed the enhanced release and accumulation of drugs in the acidic lysosomal compartments in comparison with liposomes without coiled coils.

Tumor exosomes: cellular postmen of cancer diagnosis and personalized therapy.

Nanosized (30-150 nm) extracellular vesicles 'exosomes' are secreted by cells for intercellular communication during normal and pathological conditions. Exosomes carry biomacromolecules from cell-of-origin and, therefore, represent molecular bioprint of the cell. Tumor-derived exosomes or TDEx modulate tumor microenvironment by transfer of macromolecules locally as well as at distant metastatic sites. Due to their biological stability, TDEx are rich source of biomarkers in cancer patients. TDEx focused cancer diagnosis allows liquid biopsy-based tumor typing and may facilitate therapy response monitoring by developing novel exosomes diagnostics. Therefore, efficient and specific capturing of exosomes for subsequent amplification of the biomessages; for example, DNA, RNA, miRNA can reinvent cancer diagnosis. Here, in this review, we discuss advancements in exosomes isolation strategies, presence of exosomes biomarkers and importance of TDEx in gauging tumor heterogeneity for their potential use in cancer diagnosis, therapy.

Cancer stem cell-vascular endothelial cell interactions in glioblastoma.

Glioblastoma (GBM), a higher grade glial tumor, is highly aggressive, therapy resistant and often shows poor patient prognosis due to frequent recurrence. These features of GBM are attributed to presence of a significantly smaller proportion of glioma stem cells (GSCs) that are endowed with self-renewal ability, multi-potent nature and show resistance to therapy in patients. GSCs preferably take shelter close to tumor vasculature due to paracrine need of soluble factors secreted by endothelial cells (ECs) of vasculature. The physical proximity of GSCs to ECs creates a localized perivascular niche where mutual GSC-EC interactions regulate GSC stemness, migration, therapy resistance, and cellular kinetics during tumor growth. Together, perivascular niche presents a therapeutically targetable tumor structure for clinical management of GBM. Thus, understanding cellular and non-cellular components in perivascular niche is vital for designing in vitro and in vivo GBM tumor models. Here, we discuss the components and structure of tumor vascular niche and its impact on tumor progression.

Tumor suppressive miRNA-34a suppresses cell proliferation and tumor growth of glioma stem cells by targeting Akt and Wnt signaling pathways.

MiRNA-34a is considered as a potential prognostic marker for glioma, as studies suggest that its expression negatively correlates with patient survival in grade III and IV glial tumors. Here, we show that expression of miR-34a was decreased in a graded manner in glioma and glioma stem cell-lines as compared to normal brain tissues. Ectopic expression of miR-34a in glioma stem cell-lines HNGC-2 and NSG-K16 decreased the proliferative and migratory potential of these cells, induced cell cycle arrest and caused apoptosis. Notably, the miR-34a glioma cells formed significantly smaller xenografts in immuno-deficient mice as compared with control glioma stem cell-lines. Here, using a bioinformatics approach and various biological assays, we identify Rictor, as a novel target for miR-34a in glioma stem cells. Rictor, a defining component of mTORC2 complex, is involved in cell survival signaling. mTORC2 lays downstream of Akt, and thus is a direct activator of Akt. Our earlier studies have elaborated on role of Rictor in glioma invasion (Das et al., 2011). Here, we demonstrate that miR34a over-expression in glioma stem cells profoundly decreased levels of p-AKT (Ser473), increased GSK-3ß levels and targeted for degradation ß-catenin, an important mediator of Wnt signaling pathway. This led to diminished levels of the Wnt effectors cyclin D1 and c-myc. Collectively, we show that the tumor suppressive function of miR-34a in glioblastoma is mediated via Rictor, which through its effects on AKT/mTOR pathway and Wnt signaling causes pronounced effects on glioma malignancy.