Clinical, Radiological, Pathological Features and Seizure Outcome With Surgical Management of Polymorphous Low-Grade Neuroepithelial Tumor of the Young Associated With Epilepsy.

Objective: Polymorphous low-grade neuroepithelial tumor of the young (PLNTY) is a novel distinct epileptogenic neoplasm, and its clinical, imaging, histopathological, and molecular features were already known in the existing literature. We aimed to analyze the surgical management of PLNTY combined with these known characteristics. Methods: Eight patients underwent surgical treatment in our center between December 2017 and December 2020, and the postoperative pathology was diagnosed as PLNTY. Their clinical data, imaging, pathological, molecular characteristics, and seizure outcome were retrospectively analyzed. Follow-up evaluations and a literature review were performed. Results: The 8 patients included 1 woman and 7 men, aged between 5 and 51 years old (mean = 31.6, median = 29). The preoperative symptoms of all 8 cases were seizures. Four tumors were situated in the temporal lobes, and one of the four extratemporal tumors was in the occipital lobe and three were in the frontal lobe. Enlarged and gross total resections were performed in 2 cases and the other 6 cases, respectively. All cases exhibited intense labeling of CD34, and absence of 1p/19q codeletion and IDH1 or IDH2 mutation. B-Raf proto-oncogene (BRAF) V600E mutation was presented in 4 (66.7%) of 6 detected cases. The postoperative seizure outcome of Engel class I was achieved in 6 cases (75%). Conclusion: PLNTY represents distinctive histologic, immunophenotypic and biomolecular features, and has high epileptogenicity. Early surgical intervention and enlarged resection of PLNTY associated with epilepsy will help to improve the postoperative seizure-free rate.

Surgical resection of dysembryoplatic neuroepithelioma tumor associated with epilepsy based on imaging classification.

OBJECTIVE: Dysembryoplastic neuroepithelioma tumors (DNETs) are rare glioneuronal tumors usually present with partial epilepsy. We analyzed the surgical curative effect of DNETs based on imaging classification. METHODS: The clinical, neuroimaging, seizure history, neuropathological data, and other medical records of 21 cases of cerebral hemisphere DNETs were collected and analyzed retrospectively. According to the magnetic resonance imaging (MRI) classification of Chassoux, these cases were divided into 8 cases of type I (thylakoid type), 6 cases of type II (nodular type), and 7 cases of type III (dysplasia). All patients received detailed preoperative evaluation and underwent surgical treatment. We statistically compared the postoperative seizure outcome of different DNET MRI types by Engel classification. RESULTS: All tumors were surgically removed and pathologically diagnosed as DNETs. The follow-up period was 5-68 months Engel class I outcome was achieved in all type I cases, 3 (50%) type II cases, and 3 (42.9%) type III cases. The postoperative seizure outcome of MRI type I was better than that of type II and III. CONCLUSION: Based on the MRI classification of DNET by Chassoux, the postoperative epilepsy control of type I is better than that of type II and type III, which may be related to the residual FCD around the tumor of type II and type III. Thus, the MRI classification of DNET can contribute to the preoperative design of the resection plan. Total resection of type I and extended resection of type II, as well as type III, will help to improve the postoperative seizure-free rate in DNET.

Overexpressed microRNA-494 represses RIPK1 to attenuate hippocampal neuron injury in epilepsy rats by inactivating the NF-κB signaling pathway.

OBJECTIVE: The effects of microRNAs (miRNAs) have been identified in epilepsy (Ep) in recent years, our research was focused on the functions of miR-494 in Ep and its inner mechanisms. METHODS: The Ep modeled rats induced by lithium chloride-pilocarpine were treated with agomir-miR-494 or RIPK1-siRNA. The pathology of rat hippocampal tissues was observed. Expression of miR-494, receptor-interacting protein kinase 1 (RIPK1) and nuclear factor-kappaB (NF-κB) p65 was assessed by RT-qPCR and Western blot analysis. The hippocampal neurons of epileptic rats were successfully modeled, which were transfected with miR-494 mimics or RIPK1-siRNA to determine neurons' proliferation ability and cell apoptosis. The target relation between miR-494 and RIPK1 was measured by bioinformatics website and dual luciferase gene reporter assay. RESULTS: The expression of miR-494 was reduced, while the expression of RIPK1 and NF-κB p65 was amplified in hippocampus of Ep rats. Elevated miR-494 repressed the expression of RIPK1 to ameliorate the hippocampal neuron injury, accelerate neuronal proliferation, and restrain neuronal apoptosis via inactivating the NF-κB signaling pathway, causing a deceleration of Ep development. Furthermore, amplified RIPK1 was able to reverse the amelioration of neuronal injury in Ep rats which was contributed by upregulated miR-494. CONCLUSION: We found in this study that elevated miR-494 repressed RIPK1, causing an inactivation of the NF-κB signaling pathway and acceleration of cell proliferation, and suppression of apoptosis of hippocampal neurons in Ep rats, thereby attenuating the neuron injury and Ep development. Our research may provide novel targets for the therapy of Ep.

Thalamocortical structural connectivity abnormalities in drug-resistant generalized epilepsy: A diffusion tensor imaging study.

BACKGROUND AND PURPOSE: Epilepsy is one of the most common diseases of the nervous system. Approximately one-third of epilepsy cases are drug-resistant, among which generalized-onset seizures are very common. The present study aimed to analyze abnormalities of the thalamocortical fiber pathways in each hemisphere of the brains of patients with drug-resistant generalized epilepsy. MATERIALS AND METHODS: The thalamocortical structural pathways were identified by diffusion tensor imaging (DTI) in 15 patients with drug-resistant generalized epilepsy and 16 gender/age-matched controls. The thalami of both groups were parcellated into subregions according to the local thalamocortical connectivity pattern. DTI measures of thalamocortical connections were compared between the two groups. RESULTS: Probabilistic tractography analyses showed that fractional anisotropy of thalamocortical pathways in patients with epilepsy decreased significantly, and the radial diffusivity of the left thalamus pathways with homolateral motor and parietal-occipital cortical regions in the drug-resistant epilepsy group increased significantly. In addition to the right thalamus pathway and prefrontal cortical region, fractional anisotropy of all other pathways was inversely correlated with disease duration. CONCLUSION: The results provide evidence indicating widespread bilateral abnormalities in the thalamocortical pathways in epilepsy patients and imply that the degree of abnormality in the pathway increases with the disease duration.

Retractorless Surgery for Giant Vestibular Schwannomas via the Retrosigmoid Approach.

BACKGROUND: A fixed retractor is routinely used during surgery for vestibular schwannoma to maintain the surgical corridor; however, brain injuries can be caused by use of retractors. The aim of this study was to present strategies for retractorless surgery for giant vestibular schwannomas and compare retractorless surgery with traditional retractor-assisted surgery to illustrate feasibility and potentially superiority of retractorless surgery. METHODS: Clinical data of 61 patients with giant (≥4 cm diameter) vestibular schwannomas undergoing craniotomy were retrospectively analyzed. Patients were divided into 2 cohorts: 1) 35 patients with traditional retractor surgery performed between June 2016 and July 2017; 2) 26 patients with retractorless surgery performed between June 2016 and July 2018. Duration of operation, intraoperative blood loss, extent of resection, rate of retention of facial nerve function, postoperative brain injury rate, intracranial infection rate, hospitalization time, and grade of facial nerve function were compared between the 2 groups. RESULTS: The incidence of postoperative brain injury was 3.84% in the retractorless surgery group, which was significantly lower compared with the traditional retractor surgery group (22.86%) (P < 0.05). No significant differences were found regarding the other characteristics compared. CONCLUSIONS: Through appropriate comprehensive measures, retractorless surgery for giant vestibular schwannomas is an achievable goal. This procedure can reduce the incidence of postoperative brain injury with satisfactory tumor resection.

The long non-coding RNA CRNDE acts as a ceRNA and promotes glioma malignancy by preventing miR-136-5p-mediated downregulation of Bcl-2 and Wnt2.

The colorectal neoplasia differentially expressed (CRNDE) gene encodes a long non-coding RNA (lncRNA) that is the most unregulated among 129 lncRNAs differentially expressed in gliomas. In this study, we confirmed high CRNDE expression in clinical glioma specimens and observed through experiments in human glioma cell lines a novel molecular mechanism by which CRNDE may contribute to glioma pathogenesis. By inducing or silencing CRNDE expression, we detected a positive correlation between CRNDE levels and the proliferative, migratory, and invasive capacities of glioma cells, which were concomitant with a decreased apoptosis rate. Our experiments also suggest that these effects are mediated by downregulation of miR-136-5p, which correlated with the glioma WHO grade. Based on predicted CRNDE/miR-136-5p/mRNA interactions, both the mRNA and protein expression analyses suggested that miR-136-5p-mediated repression of Bcl-2 and Wnt2 underlies the pro-tumoral actions of CRNDE. We therefore propose that CRNDE functions as a competing endogenous RNA (ceRNA) that binds to and negatively regulates miR-136-5p, thereby protecting Bcl-2 and Wnt2 from miR-136-5p-mediated inhibition in glioma.

The analysis of differential induction of hsp70 in the related cerebral domains and nerve fibers of rats after proteasome inhibiton.

BACKGROUND: Parkinson's disease (PD) is popularly called "proteins conformation disease". Heat shock proteins (Hsps) are essential molecular chaperones that handle abnormal protein conformations. The hsp70 family, in particular, represents the most highly conserved molecular chaperones. They constitute a central part of a Ubiquitous-chaperone system. PURPOSE: In the present study, we tested if the induction of hsp70 after proteasome inhibition follows a differential pattern in the related cerebral domains and nerve fibers of rats. METHODS: We used RT-PCR, stereotactic delivery method and immunohistochemical analysis as the molecular tools of investigation. RESULTS: With regard to cerebral domains, the induction of hsp70 exhibited regionality and time-dependence. The intensity of hsp70 expression varied as follows: hippocampus > substantia nigra > frontal lobe > olfactory tract, especially following the order: CA3 > CA2 > CA1 in hippocampus. As for the nerve fibers, it was interesting to find that hsp70 induction was prominent in corpus striatum of lactacystin-treated rats, however hsp70 induction was not observed in the corpus callosum. CONCLUSION: Our study shows the differential induction of hsp70 in Dopamine (DA) nerve fibers and cerebral-association fibers, indicating that hsp70 could protect extrapyramidal system (corpus striatum), not pyramidal system (corpus callosum).