lncRNA Signature for Predicting Cerebral Vasospasm in Patients with SAH: Implications for Precision Neurosurgery

Hidden regulators: the emerging roles of lncRNAs in brain development and disease

Long non-coding RNAs (lncRNAs) have emerged as critical players in brain development and disease. These non-coding transcripts, which once considered as "transcriptional junk," are now known for their regulatory roles in gene expression. In brain development, lncRNAs participate in many processes, including neurogenesis, neuronal differentiation, and synaptogenesis. They employ their effect through a wide variety of transcriptional and post-transcriptional regulatory mechanisms through interactions with chromatin modifiers, transcription factors, and other regulatory molecules. Dysregulation of lncRNAs has been associated with certain brain diseases, including Alzheimer's disease, Parkinson's disease, cancer, and neurodevelopmental disorders. Altered expression and function of specific lncRNAs have been implicated with disrupted neuronal connectivity, impaired synaptic plasticity, and aberrant gene expression pattern, highlighting the functional importance of this subclass of brain-enriched RNAs. Moreover, lncRNAs have been identified as potential biomarkers and therapeutic targets for neurological diseases. Here, we give a comprehensive review of the existing knowledge of lncRNAs. Our aim is to provide a better understanding of the diversity of lncRNA structure and functions in brain development and disease. This holds promise for unravelling the complexity of neurodevelopmental and neurodegenerative disorders, paving the way for the development of novel biomarkers and therapeutic targets for improved diagnosis and treatment.

Roles of lncRNAs in brain development and pathogenesis: Emerging therapeutic opportunities

The human genome is pervasively transcribed, producing a majority of short and long noncoding RNAs (lncRNAs) that can influence cellular programs through a variety of transcriptional and post-transcriptional regulatory mechanisms. The brain houses the richest repertoire of long noncoding transcripts, which function at every stage during central nervous system development and homeostasis. An example of functionally relevant lncRNAs is species involved in spatiotemporal organization of gene expression in different brain regions, which play roles at the nuclear level and in transport, translation, and decay of other transcripts in specific neuronal sites. Research in the field has enabled identification of the contributions of specific lncRNAs to certain brain diseases, including Alzheimer's disease, Parkinson's disease, cancer, and neurodevelopmental disorders, resulting in notions of potential therapeutic strategies that target these RNAs to recover the normal phenotype. Here, we summarize the latest mechanistic findings associated with lncRNAs in the brain, focusing on their dysregulation in neurodevelopmental or neurodegenerative disorders, their use as biomarkers for central nervous system (CNS) diseases in vitro and in vivo, and their potential utility for therapeutic strategies.

Noncoding RNA as Diagnostic and Prognostic Biomarkers in Cerebrovascular Disease

Noncoding RNAs (ncRNAs), such as microRNAs, long noncoding RNAs, and circular RNAs, play an important role in the pathophysiology of cerebrovascular diseases (CVDs). They are effectively detectable in body fluids, potentially suggesting new biomarkers for the early detection and prognosis of CVDs. In this review, the physiological functions of circulating ncRNAs and their potential role as diagnostic and prognostic markers in patients with cerebrovascular diseases are discussed, especially in acute ischemic stroke, subarachnoid hemorrhage, and moyamoya disease.

Suppression of MALAT1 alleviates neurocyte apoptosis and reactive oxygen species production through the miR-499-5p/SOX6 axis in subarachnoid hemorrhage

Subarachnoid hemorrhage (SAH), a common devastating cerebrovascular accident, is a great threat to human health and life. Exploration of the potential therapeutic target of SAH is urgently needed. Previous studies showed that long noncoding RNA metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) promotes cell apoptosis in various diseases, while its role in SAH remains unclear. In our study, we established a mouse model of SAH and used the oxyhemoglobin (OxyHb) to induce neuronal injury in vitro. Interestingly, MALAT1 was found upregulated in brain tissues of SAH mice and OxyHb-stimulated neurons. In addition, knockdown of MALAT1 attenuated apoptosis and decreased reactive oxygen species (ROS) production in OxyHb-stimulated neurons. Mechanistically, we demonstrated that MALAT1 bound with miR-499-5p. Furthermore, our findings indicated that miR-499-5p bound to SOX6 3' untranslated region (UTR) and negatively regulated SOX6 mRNA and protein levels. Rescue assays suggested that SOX6 overexpression counteracted the effects of MALAT1 knockdown on neurocyte apoptosis, and ROS production in OxyHb-stimulated neurons. The in vivo assays indicated that knockdown of MALAT1 improved brain injury of SAH mice. Our study demonstrates that silencing of MALAT1 alleviates neurocyte apoptosis and reduces ROS production through the miR-499-5p/SOX6 axis after SAH injury.

Evolving Landscape of Long Non-coding RNAs in Cerebrospinal Fluid: A Key Role From Diagnosis to Therapy in Brain Tumors

Long non-coding RNAs (lncRNAs) are a type of non-coding RNAs that act as molecular fingerprints and modulators of many pathophysiological processes, particularly in cancer. Specifically, lncRNAs can be involved in the pathogenesis and progression of brain tumors, affecting stemness/differentiation, replication, invasion, survival, DNA damage response, and chromatin dynamics. Furthermore, the aberrations in the expressions of these transcripts can promote treatment resistance, leading to tumor recurrence. The development of next-generation sequencing technologies and the creation of lncRNA-specific microarrays have boosted the study of lncRNA etiology. Cerebrospinal fluid (CSF) directly mirrors the biological fluid of biochemical processes in the brain. It can be enriched for small molecules, peptides, or proteins released by the neurons of the central nervous system (CNS) or immune cells. Therefore, strategies that identify and target CSF lncRNAs may be attractive as early diagnostic and therapeutic options. In this review, we have reviewed the studies on CSF lncRNAs in the context of brain tumor pathogenesis and progression and discuss their potential as biomarkers and therapeutic targets.

microRNA Prognostic Signature for Postoperative Success of Metastatic Orthopedic Cancers: Implications for Precision Microsurgery

The importance of miRNA prognostic signature in cancer, particular cancer metastasis is increasingly being realized. Bone metastasis from several primary human cancers can be managed in clinics by surgical intervention but the prognostic impact of miRNA signature on post-surgery outcome of patients is unknown. This study evaluated a miRNA signature for post-operative outcome of patients with bone metastatic disease. First, the miRNAs, miR-135, miR-203, miR-10b, miR-194, miR-886, and miR-124 were evaluated in bone metastatic tissues, relative to adjacent control tissue. The cohorts of samples (n = 44) consisted of bone metastatic cancer patients with primary lung (n = 18) or breast cancer (n = 26). miR-203 was significantly down-regulated while miR-10b was significantly up-regulated in bone metastasis. Additionally, miR-135 was significantly differentially expressed in the primary lung cancer patients while miR-194 in primary breast cancer patients. The low miR-203- high miR-10b expression was designated high risk group and, compared to the low risk group (high miR-203-low miR-10b expression). Patients with the signature high risk fared significantly better with surgical intervention, in terms of survival at 12 months time point (40% survival with surgery vs. 10% survival without surgery), as revealed by retrospective analysis of patient data. This work reveals potential utilization of miRNA expression levels in not only the general prognosis of cancer metastasis but also the prognosis of surgical intervention with implication for better stratification of patients.

Long non-coding RNAs mediate cerebral vascular pathologies after CNS injuries

Central nervous system (CNS) injuries are one of the leading causes of morbidity and mortality worldwide, accompanied with high medical costs and a decreased quality of life. Brain vascular disorders are involved in the pathological processes of CNS injuries and might play key roles for their recovery and prognosis. Recently, increasing evidence has shown that long non-coding RNAs (lncRNAs), which comprise a very heterogeneous group of non-protein-coding RNAs greater than 200 nucleotides, have emerged as functional mediators in the regulation of vascular homeostasis under pathophysiological conditions. Remarkably, lncRNAs can regulate gene transcription and translation, thus interfering with gene expression and signaling pathways by different mechanisms. Hence, a deeper insight into the function and regulatory mechanisms of lncRNAs following CNS injury, especially cerebrovascular-related lncRNAs, could help in establishing potential therapeutic strategies to improve or inhibit neurological disorders. In this review, we highlight recent advancements in understanding of the role of lncRNAs and their application in mediating cerebrovascular pathologies after CNS injury.

Silencing long non-coding RNA zinc finger antisense 1 restricts secondary cerebral edema and neuron injuries after traumatic brain injury

OBJECTIVE

To investigate the interaction of long non-coding RNA zinc finger antisense 1 (lncRNA ZFAS1) in secondary cerebral edema (CE) and neuron injuries after traumatic brain injury (TBI) in a mouse model.

METHODS

TBI mouse models was established by free-fall strike. Adeno-associated virus-short hairpin-ZFAS1 was administrated into mice via intracerebral injection to downregulate lncRNA ZFAS1. LncRNA ZFAS1 in mouse brain was examined. Neurological severity score (NSS), cerebral water content (CWC) and lesion volume were measured. The number of TUNEL-positive cells in brain tissue was accessed. Bax and cleaved caspase-3 in brain tissues were measured by western blot analysis, and pro-inflammatory factor levels were detected.

RESULTS

LncRNA ZFAS1 expression was upregulated in mouse brain tissues 3 days after TBI modelling. After the knockdown of lncRNA ZFAS1, NSS, CWC and lesion volume were decreased, apoptotic gene levels were decreased and pro-inflammatory cytokine levels were reduced, suggesting that lncRNA ZFAS1 knockdown could alleviate TBI-induced brain injuries in mice.

CONCLUSION

This study demonstrated that silencing lncRNA ZFAS1 inhibited TBI by quenching apoptosis, reducing inflammatory response and improving the recovery of neurological function in TBI mice. LncRNA ZFAS1 might function as a possible curative management in secondary CE and neuron injury in TBI mice.