Usefulness of Opening the Diaphragma Sellae Before Transecting Interclinoidal Ligament for Endoscopic Endonasal Transoculomotor Triangle Approach: Technical Nuances and Surgical Outcomes.

OBJECTIVE: Opening the oculomotor triangle (OT) and removing the posterior fossa lesion by endoscopic endonasal approach (EEA) is challenging for even an experienced endoscopic neurosurgeon. We summarize the treatment experience and technical nuances with EEA for resection of pituitary neuroendocrine tumors and cavernous sinus (CS) meningiomas invading through the OT. METHODS: Between 2018 and 2022, 8 patients, comprising 5 with pituitary neuroendocrine tumors (3 with nonfunctioning and 2 with somatotroph tumors with increased levels of growth hormone) and 3 CS meningiomas, were treated using an endoscopic endonasal transoculomotor triangle approach. The critical surgical technique is continuously opening the diaphragma sellae from medial to lateral toward the interclinoidal ligament and transecting it to enlarge the OT. We evaluated preoperative tumor size, previous surgical history, preoperative symptoms, extent of tumor resection, histopathology, and postoperative complications for all patients. RESULTS: The gross total resection (defined as complete removal) in 3 patients (38%), near-total resection (defined as >95% removal) in 4 patients (50%), and subtotal resection (defined as ≤90% removal) in 1 patient (12%) and gross total resection of tumor invading through the OT was achieved in all patients through pure EEA. Two of 3 patients with visual deficits in nonfunctioning pituitary neuroendocrine tumors improved, and the other remained stable postoperatively. One patient showed transient oculomotor nerve palsy. The growth hormone level of the 2 patients with somatotroph tumors declined to normal. For 3 patients with CS meningiomas, cranial nerve palsy improved in 2 patients, whereas the other patient developed increased facial numbness after surgery. CONCLUSIONS: The endoscopic endonasal transoculomotor triangle approach is an efficient surgical option for tumors with CS invasion and OT penetration.

Nucleo-cytoplasmic shuttling of 14-3-3 epsilon carrying hnRNP C promotes autophagy.

Translocation of 14-3-3 protein epsilon (14-3-3ε) was found to be involved in Triptolide (Tp)-induced inhibition of colorectal cancer (CRC) cell proliferation. However, the form of cell death induced by 14-3-3ε translocation and mechanisms underlying this effect remain unclear. This study employed label-free LC-MS/MS to identify 14-3-3ε-associated proteins in CRC cells treated with or without Tp. Our results confirmed that heterogeneous nuclear ribonucleoproteins C1/C2 (hnRNP C) were exported out of the nucleus by 14-3-3ε and degraded by ubiquitination. The nucleo-cytoplasmic shuttling of 14-3-3ε carrying hnRNP C mediated Tp-induced proliferation inhibition, cell cycle arrest and autophagic processes. These findings have broad implications for our understanding of 14-3-3ε function, provide an explanation for the mechanism of nucleo-cytoplasmic shuttling of hnRNP C and provide new insights into the complex regulation of autophagy.

Percutaneous balloon compression for trigeminal neuralgia: experience and surgical techniques from a single institution.

OBJECTIVE: The treatment experience and the technical skill with percutaneous balloon compression (PBC) for treatment of primary trigeminal neuralgia (TN) were summarised in a single institution. METHODS: This is a retrospective review including consecutive patients with typical symptoms of uni-lateral primary TN who underwent PBC from June 2020 to September 2021 in our institution. We excluded secondary aetiologies of TN. Patient demographics, surgical techniques and outcomes were reviewed. All included patients were initially managed with carbamazepine before PBC. RESULTS: A total of 70 patients were included. The mean length of follow-up was 10.6 months. Sixty-nine (98.6%) were successfully treated, and only one patient failed due to particularly narrow foramen ovale. Amongst successfully treated patients, 68 (97.1%) had immediate pain relief, with one having delayed relief. Sixty-eight patients (97.1%) had immediate facial numbness post-operatively and one (1.4%) presented delayed numbness 7 days after surgery. In the last follow-up, regarding facial numbness, 22 (31.9%) patients had complete resolution, whilst 46 (67.6%) had different degrees of benefit. Forty-nine (71.0%) patients developed masseter muscle weakness with recovery at 3-month follow-up. No anaesthesia dolorosa, keratitis, intracranial infection or death occurred in this study. CONCLUSION: PBC for treatment of TN has quick and effective result, and could be safely performed under general anaesthesia without discomfort to the patient. The common postoperative complications are facial numbness and masseter muscle weakness, with most being improved or recovered at follow-up.

Triptolide reverses epithelial-mesenchymal transition in glioma cells via inducing autophagy.

BACKGROUND: To observe the effects of triptolide (TP) on the proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) of glioma cells, and to explore the possible mechanisms of phenotypic changes in EMT. METHODS: The U87 and U251 glioma cell lines were treated TP. The Cell Counting Kit-8 (CCK-8) method was used to detect the half-maximal inhibitory concentration (IC50) of TP in these two cell lines and the inhibition of cell proliferation at the IC50 concentration. The wound-healing experiment and Transwell invasion assay were used to detect the cells' migration and invasion abilities, respectively. Using western blot protocol, the expression levels of the EMT markers were analyzed, and the levels of the autophagy markers were also detected. The pEGFP-C2-LC3B plasmid was transfected into glioma cells, and the effect of TP on autophagy was detected by immunofluorescence. A subcutaneous tumor model in nude mice was established to observe the effect of TP on cell proliferation in vivo, and immunohistochemistry (IHC) was used to detect the expression levels of EMT markers in mouse tumor tissues. RESULTS: TP significantly inhibited the proliferation of U87 and U251 cells in a dose- and time-dependent manner. TP had a significant inhibitory effect on the migration and invasion of U87 and U251 cells. Western blot showed that TP reversed the process of EMT in glioma cells, which was evidenced by the upregulated expression of the epithelial marker E-cadherin, and the downregulated expression of the mesenchymal markers N-cadherin, Vimentin, ZEB1, Snail, and Slug. TP increased autophagy in glioma cells, increased the LC3B II/I ratio, and upregulated Beclin-1 and Atg-7 expression. Immunofluorescence showed that the number of autophagosomes increased significantly after TP was applied to cells. In the nude mouse subcutaneous tumor model, experiments revealed an inhibitory effect of TP on glioma cell proliferation in vivo. IHC confirmed that the expression of E-cadherin was upregulated in mouse tumor tissues, while the expression levels of N-Cadherin and Vimentin were downregulated. CONCLUSIONS: TP can inhibit glioma cell proliferation, migration, and invasion, and reverse EMT progression. The possible mechanism of EMT reversal in glioma cells is that TP induces autophagy.

Selection and Prognosis of Optic Canal Decompression for Traumatic Optic Neuropathy.

OBJECTIVE: To comprehensively compare the vision improvement rate in patients with traumatic optic neuropathy with different surgical timing and other different preoperative conditions. METHODS: PubMed, Embase, and MEDLINE Ovid were searched to identify studies. We performed subgroup analyses for differences in the surgical timing, surgical approach, optic canal fractures, state of consciousness after trauma, time of visual loss development, incision of the optic nerve sheath, and treatment methods. RESULTS: A total of 74 studies involving 6084 patients were included in the final analysis. In the groups of patients with early (≤3 days), middle (4-7 days), and late (>7 days) surgical interventions, 58.4%, 53.2%, and 45.4% demonstrated visual improvements, respectively. The results of the statistical analysis revealed that patients with early surgical intervention had a higher improvement rate than patients with late surgical intervention (P = 0.00953). The improvement rate was significantly lower for patients who presented with no light perception before surgery than for patients whose vision was better than no light perception (relative risk, 0.498; 95% confidence interval [CI], 0.443-0.561; P = 0.001) and lower for patients with immediate visual loss after trauma than for those with secondary visual loss (relative risk, 0.639; 95% CI, 0.498-0.819; P = 0.001). CONCLUSIONS: We recommend that patients seek medical treatment as soon as possible after traumatic optic nerve injury, and patients with secondary injuries can have a good recovery effect while still living with light perception or more. The option of treatment and whether to incise the optic nerve sheath still remains controversial.

Human marrow stromal cells secrete microRNA-375-containing exosomes to regulate glioma progression.

It is well established that human marrow stromal cells (hMSCs) can directly migrate towards tumor microenvironments associated with tumor formation and intracellular communication. Gene regulatory networks in tumors may be targeted by microRNAs (miRNAs), especially those derived in exosomes from hMSCs. However, the potential functional roles of hMSCs in glioma cell growth still remain controversial. Therefore, this study aimed at exploring the regulatory mechanisms of hMSC exosomal microRNA-375 (miR-375) in glioma. Microarray analysis was used to initially screen out glioma-related genes. The interaction between miR-375 and solute carrier family 31 member 1 (SLC31A1) was confirmed by dual-luciferase reporter gene assay. miR-375 and SLC31A1 expression in glioma cells were determined. Glioma cells were initially exposed to exosomes derived from hMSCs treated with miR-375. Subsequently, the rates of proliferation, migration, invasion and apoptosis were determined in glioma cells using in vitro assays. The effects of exosomal miR-375 from hMSCs on tumor growth in vivo were also measured using xenograft tumor in nude mice. We found that miR-375 and SLC31A1 showed significantly lower and higher expression of glioma cells respectively. Additionally, restored miR-375 expression resulted in suppressed cell proliferation, migration and invasion, and increased apoptosis by targeting SLC31A1. Next, in vitro experiments demonstrated that hMSC-derived exosomes overexpressing miR-375 promoted apoptosis while suppressing proliferation, migration and invasion. Furthermore, in vivo experiments confirmed the negative regulatory effects of hMSC-derived exosomes with overexpressed miR-375. We conclude that exosomal miR-375 from hMSCs inhibits glioma cell progression through SLC31A1 suppression, and ultimately serves as a potential target in the treatment of gliomas.

Acquired temozolomide resistance in MGMT-deficient glioblastoma cells is associated with regulation of DNA repair by DHC2.

The acquisition of temozolomide resistance is a major clinical challenge for glioblastoma treatment. Chemoresistance in glioblastoma is largely attributed to repair of temozolomide-induced DNA lesions by O6-methylguanine-DNA methyltransferase (MGMT). However, some MGMT-deficient glioblastomas are still resistant to temozolomide, and the underlying molecular mechanisms remain unclear. We found that DYNC2H1 (DHC2) was expressed more in MGMT-deficient recurrent glioblastoma specimens and its expression strongly correlated to poor progression-free survival in MGMT promotor methylated glioblastoma patients. Furthermore, silencing DHC2, both in vitro and in vivo, enhanced temozolomide-induced DNA damage and significantly improved the efficiency of temozolomide treatment in MGMT-deficient glioblastoma. Using a combination of subcellular proteomics and in vitro analyses, we showed that DHC2 was involved in nuclear localization of the DNA repair proteins, namely XPC and CBX5, and knockdown of either XPC or CBX5 resulted in increased temozolomide-induced DNA damage. In summary, we identified the nuclear transportation of DNA repair proteins by DHC2 as a critical regulator of acquired temozolomide resistance in MGMT-deficient glioblastoma. Our study offers novel insights for improving therapeutic management of MGMT-deficient glioblastoma.

miR-1268a regulates ABCC1 expression to mediate temozolomide resistance in glioblastoma.

INTRODUCTION: Temozolomide (TMZ) is the preferred chemotherapeutic drug approved for the Glioblastoma multiforme (GBM) treatment. However, resistance to TMZ is the most intractable challenge for treatment of GBM. Screening of miRNAs is becoming a novel strategy to reveal underlying mechanism of drug-resistance of human tumors. MATERIALS AND METHODS: We conducted RNA sequencing (RNA-seq) for GBM cells treated continuously with TMZ 1 or 2 week or not. Bioinformatic analysis was used to predict targets of these altered miRNAs. Subsequently, we studied the potential role of miR-1268a in TMZ-resistance of GBM cells. RESULTS: Expression levels of 55 miRNAs were identified altering both after 1 and 2 weeks TMZ treatment. Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were conducted to illuminate the biological implication and related pathways of predicted target genes. We showed that miR-1268a was downregulated after TMZ treatment and targeted ABCC1/MRP1, a membrane transporter contributing to drug resistance, using dual-luciferase assay. Furthermore, we confirmed overexpression of miR-1268a inhibited protein translation of ABCC1 and restored upregulated expression of ABCC1 due to TMZ. Inversely, knockdown of miR-1268a increased ABCC1 at protein level and enhanced upregulation of ABCC1 with TMZ treatment. In addition, our data indicated that miR-1268a enhanced TMZ sensitivity in GBM cells. CONCLUSION: Through RNA-seq analysis, we discovered miR-1268a and elucidated its role in modulating TMZ-resistance of GBM cells by targeting ABCC1.

Identification of Key Candidate Proteins and Pathways Associated with Temozolomide Resistance in Glioblastoma Based on Subcellular Proteomics and Bioinformatical Analysis.

TMZ resistance remains one of the main reasons why treatment of glioblastoma (GBM) fails. In order to investigate the underlying proteins and pathways associated with TMZ resistance, we conducted a cytoplasmic proteome research of U87 cells treated with TMZ for 1 week, followed by differentially expressed proteins (DEPs) screening, KEGG pathway analysis, protein-protein interaction (PPI) network construction, and validation of key candidate proteins in TCGA dataset. A total of 161 DEPs including 65 upregulated proteins and 96 downregulated proteins were identified. Upregulated DEPs were mainly related to regulation in actin cytoskeleton, focal adhesion, and phagosome and PI3K-AKT signaling pathways which were consistent with our previous studies. Further, the most significant module consisted of 28 downregulated proteins that were filtered from the PPI network, and 9 proteins (DHX9, HNRNPR, RPL3, HNRNPA3, SF1, DDX5, EIF5B, BTF3, and RPL8) among them were identified as the key candidate proteins, which were significantly associated with prognosis of GBM patients and mainly involved in ribosome and spliceosome pathway. Taking the above into consideration, we firstly identified candidate proteins and pathways associated with TMZ resistance in GBM using proteomics and bioinformatic analysis, and these proteins could be potential biomarkers for prevention or prediction of TMZ resistance in the future.

The Differentially Expressed Genes of Human Sporadic Cerebral Cavernous Malformations.

OBJECTIVES: To understand the development of sporadic cerebral cavernous malformations (SCCM) comprehensively, we analyzed gene expression profiles in SCCMs by gene microarray. METHODS: The total number of the specimens collected in our study was 14, 7 of which were SCCMs, and the others were controls that were obtained from normal brain vessels. The total RNA was extracted and hybridized with oligonucleotide array containing 21522 genes. The analysis of Gene Ontology (GO) items and molecular pathways was performed based on the GO and Kyoto Encyclopedia of Genes and Genomes databases. The gene coexpression networks were constructed to identify the core genes regulating the progression of SCCMs. RESULTS: A total of 785 probes, showing differentially expressed genes (DEGs) between the 2 groups, were found by the gene chips. According to the analysis based on GO and Kyoto Encyclopedia of Genes and Genomes, 286 GO terms and 53 pathways were identified to be significantly relevant with the DEGs. All differential gene interactions were analyzed and the core genes were selected in the coexpression networks. CONCLUSIONS: The gene expression profiles obtained from SCCMs were significantly distinct from those of control brain vascular specimens. These DEGs are related to multiple molecular signal pathways, such as the mitogen-activated protein kinase pathway, cytokine-cytokine receptor interaction, focal adhesion, and inflammatory response. According to the analysis of the core genes selected in the gene coexpression networks, we postulated that CSF1R, XCL1, KCNMB1, RHOG, and TJP1 might exert enormous functions in the pathogenesis of SCCMs. However, further studies are required to aid in the clinical diagnosis and prevention of SCCMs.

Overexpression of COX7A2 is associated with a good prognosis in patients with glioma.

Cytochrome c oxidase subunit 7A2 (COX7A2) is a nuclear-encoded polypeptide involved in assembly and regulation of cytochrome c oxidase (COX). Changes in the respiratory chain as big complex are known to be associated with cancer, but little research has been performed to discover COX7A2 as a prognostic marker in glioma. In the present study, we investigated COX7A2 expression and its prognostic significance in glioma. Glioma surgical tissue samples were taken from 126 patients who had been followed up from 4 to 51 months. Immunohistochemistry were used to test COX7A2 expression in the 126 tumor samples. Eighty-six of 126 (68.3%) paraffin-embedded glioma biopsies showed high expression of COX7A2. Statistical analysis displayed that there was significant difference of COX7A2 expression level in patients categorized according to WHO classification. Kaplan-Meier survival analysis revealed that patients with higher COX7A2 expression had longer overall survival time and better prognosis. R2: microarray analysis based on Tumor Glioma French 284 database, Tumor Glioblastoma TCGA 540 database, and Tumor Glioma Kawaguchi 50 database testified that high expression of COX7A2 is associated with a good prognosis in patients with glioma. Multivariate analysis showed that COX7A2 high expression was an independent prognostic indicator for survival. Our results suggest that COX7A2 could be served as a valuable prognostic marker of glioma.

The purine receptor P2X7R regulates the release of pro-inflammatory cytokines in human craniopharyngioma.

Craniopharyngiomas (CPs) are usually benign, non-metastasizing embryonic malformations originating from the sellar area. They are, however, locally invasive and generate adherent interfaces with the surrounding brain parenchyma. Previous studies have shown the tumor microenvironment is characterized by a local abundance of adenosine triphosphate (ATP), infiltration of leukocytes and elevated levels of pro-inflammatory cytokines that are thought to be responsible, at least in part, for the local invasion. Here, we examine whether ATP, via the P2X7R, participates in the regulation of cytokine expression in CPs. The expression of P2X7R and pro-inflammatory cytokines were measured at the RNA and protein levels both in tumor samples and in primary cultured tumor cells. Furthermore, cytokine modulation was measured after manipulating P2X7R in cultured tumor cells by siRNA-mediated knockdown, as well as pharmacologically by using selective agonists and antagonists. The following results were observed. A number of cytokines, in particular IL-6, IL-8 and MCP-1, were elevated in patient plasma, tumor tissue and cultured tumor cells. P2X7R was expressed in tumor tissue as well as in cultured tumor cells. RNA expression as measured in 48 resected tumors was positively correlated with the RNA levels of IL-6, IL-8 and MCP-1 in tumors. Furthermore, knockdown of P2X7R in primary tumor cultures reduced, and stimulation of P2XR7 by a specific agonist enhanced the expression of these cytokines. This latter stimulation involved a Ca2+-dependent mechanism and could be counteracted by the addition of an antagonist. In conclusion, the results suggest that P2X7R may promote IL-6, IL-8 and MCP-1 production and secretion and contribute to the invasion and adhesion of CPs to the surrounding tissue.

The involvement of anterior gradient 2 in the stromal cell-derived factor 1-induced epithelial-mesenchymal transition of glioblastoma.

In recent years, it has been widely identified that the stromal cell-derived factor 1 (SDF-1) and anterior gradient 2 (AGR2) were implicated in the development of epithelial-mesenchymal transition (EMT) in a variety of cancers. However, the involvement of SDF-1-AGR2 pathway in the EMT of glioblastoma has not been investigated. In the present study, the in vitro assays were used to investigate the role of AGR2 in cell cycle, migration, and invasion. We found that the expressions of AGR2 and chemokine (C-X-C motif) receptor 4 (CXCR4) were obviously upregulated in glioblastoma cells T98G, A172, U87, and U251 than those in normal human astrocytes (NHA) (all p < 0.01), among which both U87 and U251 cells presented the highest expression (p > 0.05). Western blot revealed that SDF-1 induced the expression of p-AKT, AGR2, and EMT markers (N-cadherin, matrix metalloproteinase-2 (MMP2), and Slug) in a dose-dependent manner in U87 and U251 cells. However, the depletion of AGR2 reversed SDF-1-induced upregulation of EMT markers rather than p-AKT. Furthermore, functional analysis identified that knockdown of AGR2 induced cell cycle arrest in G0/G1 phase and suppressed the migration and invasion of U87 and U251 cells. Taken together, SDF-1-CXCR4 pathway induced the expression of AGR2 to control the progression of EMT likely via AKT pathway in the development of glioblastoma. Our findings lay a promising foundation for the SDF-1-AGR2 axis-targeting therapy in patients with glioblastoma.