Recent insights into the microRNA-dependent modulation of gliomas from pathogenesis to diagnosis and treatment (original) (raw)

Role of miRNa in glioma pathogenesis, diagnosis and therapeutic outcomes

Molecular Biology and Treatment Strategies for Gliomas [Working Title]

Glioma is the most aggressive tumor of glial cells of brain and spinal cord, even in the presence current multimodal therapeutic regimens the life expectancy of more then 2 year is very rare and it comprise 30 percent of all brain tumors. Micro RNAs (miRNAs) are short, non-coding RNAs produced naturally in the body and control gene expression. Many evidence-based hypotheses show that miRNA expression is aberrantly influenced in glioma due to amplification or deletion of miRNA genes, inappropriate transcriptional regulation of miRNAs, dysregulated epigenetic alterations, or faults in the miRNA biogenesis machinery. In some circumstances, miRNAs promote tumorigenesis, whereas under other circumstances, they can act as tumour suppressors in glioma. In glioma, miRNA involved in cell proliferation signalling, evasion of growth suppressors, resistance to cell death, tumour cell infiltration, metastasis, and angiogenesis. More and more research is pointing to miRNAs as prospective biomarke...

Exploring the Role of microRNAs in Glioma Progression, Prognosis, and Therapeutic Strategies

Cancers

Gliomas, which arise from glial cells in the brain, remain a significant challenge due to their location and resistance to traditional treatments. Despite research efforts and advancements in healthcare, the incidence of gliomas has risen dramatically over the past two decades. The dysregulation of microRNAs (miRNAs) has prompted the creation of therapeutic agents that specially target them. However, it has been reported that they are involved in complex signaling pathways that contribute to the loss of expression of tumor suppressor genes and the upregulation of the expression of oncogenes. In addition, numerous miRNAs promote the development, progression, and recurrence of gliomas by targeting crucial proteins and enzymes involved in metabolic pathways such as glycolysis and oxidative phosphorylation. However, the complex interplay among these pathways along with other obstacles hinders the ability to apply miRNA targeting in clinical practice. This highlights the importance of id...

MicroRNAs and glioblastoma: roles in core signalling pathways and potential clinical implications

Journal of Cellular and Molecular Medicine, 2011

MicroRNAs (miRNAs) are endogenously expressed small non-coding RNAs that act as post-transcriptional regulators of gene expression. Dysregulation of these molecules has been indicated in the development of many cancers. Altered expression levels of several miRNAs were identified also in glioblastoma. It was repeatedly found that miRNAs are involved in important signalling pathways, which play roles in crucial cellular processes, such as proliferation, apoptosis, cell cycle regulation, invasion, angiogenesis and stem cell behaviour. Therefore, miRNAs represent promising therapeutic targets in glioblastoma. In this review, we summarize the current knowledge about miRNAs significance in glioblastoma, with special focus on their involvement in core signalling pathways, their roles in drug resistance and potential clinical implications.

Extensive modulation of a set of microRNAs in primary glioblastoma

Biochemical and Biophysical Research Communications, 2005

MicroRNAs (miRNAs) are short non-coding RNA molecules playing regulatory roles in animals and plants by repressing translation or cleaving RNA transcripts. The specific modulation of several microRNAs has been recently associated to some forms of human cancer, suggesting that these short molecules may represent a new class of genes involved in oncogenesis. In our study, we examined by microarray the global expression levels of 245 microRNAs in glioblastoma multiforme, the most frequent and malignant of primary brain tumors. The analysis of both glioblastoma tissues and glioblastoma cell lines allowed us to identify a group of microRNAs whose expression is significantly altered in this tumor. The most interesting results came from miR-221, strongly upregulated in glioblastoma and from a set of brain-enriched miRNAs, miR-128, miR-181a, miR-181b, and miR-181c, which are down-regulated in glioblastoma.

Analysis of expression of microRNAs and genes involved in the control of key signaling mechanisms that support or inhibit development of brain tumors of different grades

Clinica Chimica Acta, 2014

Background: MicroRNAs (miRNAs) are a class of small non-coding RNA molecules involved in the regulation of key biological processes. Different miRNAs with pro-oncogenic and anti-oncogenic properties have been identified in glioblastomas. We decided to analyze expression profiles of 10 mature miRNAs (miR-7-1, miR-10а, miR-17, miR-20а, miR-21, miR-23а, miR-26а, miR-137, and miR-222) in post-surgery glioma specimens of different grades in order to find whether the expression level correlates with tumor grades. We also measured expression of six key genes such as PTEN, p21/CDKN1A, MDR1, ABCG2, BAX, and BCL-2 involved in the regulation of critical glioma signaling pathways to establish the effect of miRNAs on these signaling mechanisms. Methods: Using RT-PCR, we performed expression analysis of 25 tumor fresh samples (grades II-IV). Results: We found gradual increase in miR-21 and miR-23a levels in all tumor grades whereas miR-7 and miR-137 were significantly down-regulated depending on the glioma grade. MDR, ABCG2, and p21/CDKN1A levels were significantly up-regulated while expression of PTEN was down-regulated in tumor samples compared to the normal brain tissue. Conclusions: These observations provide new insights into molecular pathogenic mechanisms of glioma progression and suggest about a potential value of miRNAs as a putative diagnostic marker of brain tumors.

A MiRNA Signature for Defining Aggressive Phenotype and Prognosis in Gliomas

PLoS ONE, 2014

Gliomas represent a disparate group of tumours for which there are to date no cure. Thus, there is a recognized need for new diagnostic and therapeutic approaches based on increased understanding of their molecular nature. We performed the comparison of the microRNA (miRNA) profile of 8 WHO grade II gliomas and 24 higher grade tumours (2 WHO grade III and 22 glioblastomas) by using the Affymetrix GeneChip miRNA Array v. 1.0. A relative quantification method (RT-qPCR) with standard curve was used to confirm the 22 miRNA signature resulted by array analysis. The prognostic performances of the confirmed miRNAs were estimated on the Tumor Cancer Genome Atlas (TCGA) datasets. We identified 22 miRNAs distinguishing grade II gliomas from higher grade tumours. RT-qPCR confirmed the differential expression in the two patients' groups for 13 out of the 22 miRNAs. The analysis of the Glioblastoma Multiforme (GBM) and Lower Grade Glioma (LGG) datasets from TCGA demonstrated the association with prognosis for 6 of those miRNAs. Moreover, in the GBM dataset miR-21 and miR-210 were predictors of worse prognosis in both univariable and multivariable Cox regression analyses (HR 1.19, p = 0.04, and HR 1.18, p = 0.029 respectively). Our results support a direct contribution of miRNAs to glioma cancerogenesis and suggest that miR-21 and miR-210 may play a role in the aggressive clinical behaviour of glioblastomas.

MicroRNAs in glioblastoma multiforme pathogenesis and therapeutics

Cancer medicine, 2016

Glioblastoma multiforme (GBM) is the most common and lethal cancer of the adult brain, remaining incurable with a median survival time of only 15 months. In an effort to identify new targets for GBM diagnostics and therapeutics, recent studies have focused on molecular phenotyping of GBM subtypes. This has resulted in mounting interest in microRNAs (miRNAs) due to their regulatory capacities in both normal development and in pathological conditions such as cancer. miRNAs have a wide range of targets, allowing them to modulate many pathways critical to cancer progression, including proliferation, cell death, metastasis, angiogenesis, and drug resistance. This review explores our current understanding of miRNAs that are differentially modulated and pathologically involved in GBM as well as the current state of miRNA-based therapeutics. As the role of miRNAs in GBM becomes more well understood and novel delivery methods are developed and optimized, miRNA-based therapies could provide a...

The Impacts of miRNAs in Glioblastoma Progression

Critical Reviews in Eukaryotic Gene Expression, 2016

miRNAs are short noncoding RNA sequences that cause translational repression or mRNA degradation. A growing number of studies have sought new biomarkers in GBM that will be important in disease progression and prognosis and as potential therapeutic targets. miRNA-profiling studies in glioblastoma patients have found that aberrant miRNA expression can be used as a target to develop new biomarkers for disease detection and for determining prognosis or therapeutic response. In evaluating the tumor or its therapeutic response, genetic abnormalities such as mutations, epigenetic abnormalities, and aberrant miRNA expressions can be useful markers. This review summarizes the known miRNAs according their therapeutic importance and their use as disease progression biomarkers.

Micro-masters of glioblastoma biology and therapy: increasingly recognized roles for microRNAs

Neuro-Oncology, 2014

MicroRNAs are small noncoding RNAs encoded in eukaryotic genomes that have been found to play critical roles in most biological processes, including cancer. This is true for glioblastoma, the most common and lethal primary brain tumor, for which microRNAs have been shown to strongly influence cell viability, stem cell characteristics, invasiveness, angiogenesis, metabolism, and immune evasion. Developing microRNAs as prognostic markers or as therapeutic agents is showing increasing promise and has potential to reach the clinic in the next several years. This succinct review summarizes current progress and future directions in this exciting and steadily expanding field.