Endoscopic Fenestration for Treating Galassi Type III Middle Cranial Fossa Arachnoid Cysts: Single- and Multiple-stoma have the Same Curative Effect.

BACKGROUND: For endoscopic fenestration of middle cranial fossa arachnoid cysts (MCFACs), the decisions on the location and number of stomas are key issues. However, research on this particular topic has been limited. Thus, this study aimed to compare single- versus multiple-stoma endoscopic fenestration for treating Galassi type III MCFACs. METHODS: This retrospective study included 86 patients with Galassi type III MCFACs treated with endoscopic fenestration. Single-stoma fenestration to the basal cistern was performed in 37 cases, whereas multiple-stoma fenestration to the basal cistern and the carotid cistern was performed in 49 cases. Clinicoradiologic profiles and follow-up data were analyzed. RESULTS: The rate of symptom relief was 83.7% (72/86), and the rate of cyst shrinkage was 96.5% (83/86). Postoperative ipsilateral subdural effusion, which was significant (p = 0.042), and noninfectious fever were the two most common complications in the single- and multiple-stoma groups. No significant differences in intraoperative nerve injury, vascular injury, proportion of cases with cyst reduction, and symptom remission rate were observed between the two groups. The rates of cyst recurrence and secondary surgery in the single-stoma group were higher than those in the multiple-stoma group, although the difference was not significant. CONCLUSION: Endoscopic fenestration is an effective and minimally invasive approach for treating Galassi type III MCFACs. Single- and multiple-stoma endoscopic fenestrations have the same curative effect.

Identification and Verification of SLC27A1, PTBP1 and EIF5A With Significantly Altered Expression in Aggressive Pituitary Adenomas.

Background: Aggressive pituitary adenoma encircling the internal carotid artery has a poor clinical prognosis because of a high surgical risk and a high recurrence rate. This seriously affects patients' quality of life and yet there is no effective medical treatment. The European Diagnostic Guidelines have recommended the use of temozolomide (TMZ) for these aggressive pituitary adenomas, but the treatment remission rate has been less than 50%. Methods: In this study, transcriptome sequencing of pituitary tumour tissues and TMZ-treated pituitary tumour cell lines were employed to explore the significance gene expressions affecting the efficacy of TMZ treatment for pituitary tumours. To clarify the roles of these gene expressions, six adult patients with pituitary adenomas treated in Tiantan Hospital from 2015 to 2020 and a pituitary adenoma cell line (Att20 sensitive to TMZ treatment) were analyzed by mRNA transcriptome sequencing. The differentially expressed genes were assayed by analyzing the sequencing results, and the expression level of these genes was further verified by immunohistochemistry. In addition, Ki67, VEGF, and p53 of the tumour tissues were also verified by immunohistochemistry. Results: In tumour tissues, mRNA sequencing showed that PTBP1 and EIF5A were significantly overexpressed in primary pituitary adenomas and SLC27A1 was significantly overexpressed in aggressive pituitary adenomas. Also in the pituitary adenoma cell line (AtT20), SLC27A1 expression levels were suppressed by TMZ treatment. Subsequent immunohistochemistry confirmed the sequencing results. Conclusion: High expression of SLC27A1 and low expression of EIF5A and PTBP1 may be potential indicators to predict the progression of aggressive pituitary adenomas, and patients with high SLC27A1 subtype may be sensitive to TMZ in clinical treatments.

Clinical features, radiological profiles, pathological features and surgical outcomes of pituicytomas: a report of 11 cases and a pooled analysis of individual patient data.

BACKGROUND: Pituicytoma is an extremely rare low-grade glial tumor that is closely related to the neurohypophysis axis. Most studies of pituicytomas include only several cases. To better understand this disease, we reviewed a series of cases of pituicytomas. The diagnosis and treatment of pituicytoma must be further elucidated. METHODS: Eleven patients with pituicytoma admitted to Beijing Tiantan Hospital from 2012 to 2019 were selected. The clinical features, including radiological and histological examination, surgical records and prognosis were reviewed. Sixty-eight other previously published cases of pituicytoma also were used to analyze the predictive factors for the results. The Cox regression model was used for univariate and multivariate analyses. RESULTS: Our patients included 5 males (45.5%) and 6 females (54.5%), with a mean age of 49.3 years. The tumor was located in the suprasellar region in 5 patients (45.5%), intrasellar region in 4 patients (36.4%), and intrasellar-suprasellar region in 2 patients (18.2%). All patients were misdiagnosed with other common tumors in the sellar region before the operation. During the operation, gross total resection (GTR) of the tumor was achieved in 6 patients (54.5%), and subtotal resection (STR) was achieved in 5 patients (45.5%). The mean progression-free survival (PFS) time was 29.82 months. Tumor progression after surgical resection occurred in 4 patients (36.4%). Among them, 60.0% of the patients (cases 4, 5, 7) with STR experienced progression, while 16.7% of the patients (case 2) with GTR experienced progression. Combined with the 68 cases in the literature, GTR was an independent risk factor for PFS time (P < 0.05). CONCLUSIONS: Pituicytomas are more common in middle-aged people and the sellar region. The clinical manifestations of pituicytomas are different, but no diagnostic clinical features have been identified other than an abnormally abundant blood supply. Currently, GTR is the best approach for the treatment of pituicytomas. More patients and longer follow-up periods were needed to further elucidate the biological features of pituicytomas.

LncRNA MEG8 promotes TNF-α expression by sponging miR-454-3p in bone-invasive pituitary adenomas.

There are few studies on the mechanism of pituitary adenoma (PA) destroying bone. The current study aimed to investigate the role of MEG8/miR-454-3p/TNF-α in bone-invasive pituitary adenomas (BIPAs). In this study, we report that lncRNA MEG8 and TNF-α are upregulated in BIPA tissues while miR-454-3p is downregulated, which is associated with poor progression-free survival (PFS). Functional assays revealed the role of up-regulated MEG8 and down-regulated miR-454-3p in promoting bone destruction. Mechanistically, MEG8 promotes TNF-α expression by sponging miR-454-3p, which ultimately leads to the occurrence of bone destruction. The mechanism is confirmed in vivo and in vitro. Therefore, our data illustrated a new regulatory mechanism of MEG8/miR-454-3p/TNF-α in BIPAs. It may provide a useful strategy for diagnosis and treatment for BIPA patients.

Pituitary metastasis from renal cell carcinoma: case report and review of the literature.

Pituitary metastasis(PM) from renal cell carcinoma(RCC) is rare, and is easy to be misdiagnosed. Here, we present a case of pituitary metastasis from clear-cell renal cell carcinoma(ccRCC) which was difficult to distinguish from other sellar region tumors. In addition, we systematically review the literature to find the characteristics of different tumors of the sellar region. It provides a new idea for the diagnosis of sellar region tumors in the clinic.

A good choice for the patients with prior failed ventriculoperitoneal shunt treatment of suprasellar arachnoid cysts: endoscopic fenestration.

To investigate the effectiveness of endoscopic fenestration in the patients with prior failed ventriculoperitoneal (VP) shunt treatment of suprasellar arachnoid cysts (SACs). Between 2012 and 2018, four pediatric patients of SACs with previous failed VP shunt treatment were surgically treated using endoscopic ventriculocystocisternostomy (VCC) in our hospital. The clinical symptoms, imaging data, and surgical outcomes were collected and analyzed retrospectively. A literature review is provided with regard to the reasons of shunt failure and surgical outcome of further endoscopic fenestration in the previously reported patients of SACs with prior failed VP shunt. For the 4 cases, the initial clinical symptoms relieved or even disappeared after shunt placement, but, respectively, recurred 2, 6, 11, and 6 months later. MR scans were conducted when the clinical symptoms reappeared and showed a cyst had greatly enlarged after shunt placement. Furthermore, VP shunt-related slit ventricle was also demonstrated in 3 cases. Clinical improvement and cysts shrinkage occurred in all 4 patients after VCC. Slit ventricle and hydrocephalus were also resolved. Three patients had their shunt apparatus removed after VCC, and another patient's guardian refused to remove the shunt apparatus. Subdural hematoma occurred in one case after shunt apparatus removal. Four patients have been stable during follow-up period (mean follow-up 26.5 months). All the three patients whose VP shunt were removed were shunt independence. There were 24 patients who underwent endoscopic fenestration as an alternative to the failed VP shunt treatment in the published reports. Added our 4 patients to the published group, the effective rate of endoscopic fenestration for SACs following previous failed VP shunt treatment was approximately 93% (26/28). Of the 24 patients, the shunt apparatuses were in situ or reimplantation in 9 patients due to shunt dependence. The correction to recognize the SAC is the first condition to select the optimal management philosophy. The analysis of the series suggests endoscopic operation is still an effective and safe option in the SAC patients with previous failed VP shunt, and the shunt apparatus can be removed for some patients. The short interval time between shunt operation and endoscopic fenestration is conductive to return patients to the shunt-free state.

Regulating the CCNB1 gene can affect cell proliferation and apoptosis in pituitary adenomas and activate epithelial-to-mesenchymal transition.

The aim of the present study was to investigate the role and potential regulatory mechanisms of cyclin B1 (CCNB1) in the proliferation, apoptosis and epithelial-to-mesenchymal transition (EMT) in pituitary adenomas. A total of 24 specimens were included in the present study. The expression levels of CCNB1 protein in two normal pituitary and 22 pituitary adenoma tissues were determined by western blotting. CCNB1 was knocked-down by lentiviral-mediated infection of short hairpin RNA (shRNA) in GH3 and MMQ cell lines. The proliferation, cell cycle and apoptosis of GH3 and MMQ cell lines were detected using a Cell Counting Kit-8 and flow cytometer. Reverse transcription-quantitative PCR was utilized to detect the expression level of CCNB1 gene and EMT markers. In the present study, resveratrol (RES) was used as an inhibitor of CCNB1. The protein expression level of CCNB1 in pituitary adenomas was higher than that in normal pituitary tissue, as assessed by western blot analysis. In addition, the expression level of CCNB1 in invasive pituitary adenomas was higher when comparing invasive pituitary adenomas and non-invasive pituitary adenomas. Knockdown of CCNB1 resulted in significant decreases in cell viability and proliferation, arrested cell cycle at the G2/M phase and increased apoptosis. In addition, knockdown of CCNB1 significantly decreased the expression levels of the mesothelial cell marker N-cadherin (P<0.001), but significantly increased the expression levels of the epithelial cell markers E-cadherin (P<0.01) and p120-catenin (P<0.001). Further analyses identified that RES inhibited the expression level of CCNB1, and RES treatment exhibited a similar effect as CCNB1 shRNA infection. The present study suggested that suppressing the expression level of CCNB1 could regulate the proliferation and apoptosis of pituitary tumor cells and alter the expression level of various EMT markers. In addition, RES treatment could be used as an inhibitor of CCNB1. The present study also identified the molecular mechanisms underlying CCNB1 role in EMT.

The Effects of Smad3 on Adrenocorticotropic Hormone-Secreting Pituitary Adenoma Development, Cell Proliferation, Apoptosis, and Hormone Secretion.

OBJECTIVE: Down-regulation of mothers against decapentaplegic homolog 3 (Smad3) results in the formation of tumors both in vivo and in vitro. However, little is known about the effect of Smad3 on adrenocorticotropic hormone-secreting pituitary adenomas (ACTH-PAs). Our objective was to study the expression and effect of Smad3 in ACTH-PAs and its possible mechanisms. METHODS: Smad3, COOH-terminally phosphorylated mothers against decapentaplegic homolog 3 (pSmad3), and mothers against decapentaplegic homolog 2 proteins (Smad2) were detected in samples from 5 normal anterior pituitaries and 18 ACTH-PAs by Western blot and immunohistochemical analysis. Then, Smad3 expression was up-regulated by Smad3-CMV plasmid or down-regulated by small interfering RNA in ACTH tumor cells (AtT-20) in vitro. Cell proliferation, apoptosis, ACTH level, and pSmad3, B-cell lymphoma/lewkmia-2 (BCL-2), and pro-opiomelanocortin (POMC) protein expression in the AtT-20 cells were measured to investigate the antitumor effects of Smad3. RESULTS: Reduced expression of Smad3 and pSmad3 but unchanged Smad2 levels were found in ACTH-PAs compared with normal pituitaries. In vitro, the overexpression of Smad3 inhibited cell proliferation, promoted cell apoptosis, and decreased ACTH secretion; in contrast, Smad3 knockdown increased cell proliferation and decreased cell apoptosis but had no significant effect on ACTH secretion. At the same time, overexpression of Smad3 increased pSmad3 but inhibited BCL-2 and POMC protein expression. On the contrary, underexpression of Smad3 inhibited pSmad3 but promoted BCL-2 and POMC protein expression. CONCLUSIONS: Smad3 is underexpressed in ACTH-PAs. Reversing the expression of Smad3 in AtT-20 cells could suppress cell growth, promote tumor apoptosis, and decrease ACTH secretion. Tumor suppression was possibly mediated by the promotion of pSmad3 and the reduction of BCL-2 and POMC expression.

Three-Dimensional Printed Skull Base Simulation for Transnasal Endoscopic Surgical Training.

OBJECTIVE: Transnasal endoscopic skull base surgery (SBS) presents a major challenge for inexperienced neurosurgeons because of the complicated anatomic structures, 2-dimensional endoscopic view, limited operative field, and required skills. We designed a personalized multimaterial and multicolor three-dimensional (3D)-printed SBS simulation to reproduce the complex anatomy of the skull base. The fidelity and feasibility for anatomic education and surgical training were assessed. METHODS: Two-dimensional computer tomography and magnetic resonance images were collected from a 42-year-old healthy male volunteer. After 3D modeling and spatial alignment, personalized SBS simulations were produced using a multimaterial 3D printer. The fidelity of the models was assessed by 3 experienced neurosurgeons, and the effects for anatomic education and surgical training were evaluated by 10 resident trainees. Both evaluations were based on 5-point Likert questionnaires. RESULTS: The mean scores for fidelity of tissue structure ranged from 3.7 to 4.7, and scores for aid in anatomic education and surgical training ranged from 3.5 to 4.9. CONCLUSION: The 3D-printed SBS simulation is a practical, economical, high-fidelity model. It has great potential for anatomic education and operative training in transnasal endoscopic surgery.

Short-term Preoperative Octreotide for Thyrotropin-secreting Pituitary Adenoma.

BACKGROUND: Thyrotropin-secreting pituitary adenomas (TSHomas) are a rare cause of hyperthyroidism. Somatostatin (SST) analogs work by interacting with somatostatin receptors (SSTRs). This study aimed to evaluate short-term preoperative octreotide (OCT) use in TSHoma patients and to investigate SSTR2 and SSTR5 expression and observe structural changes in tumor tissue. METHODS: We reviewed records and samples from eight TSHoma patients treated between July 2012 and July 2015. We tested immunohistochemically for SSTR2/5 expression and examined TSHoma cells for morphological changes. Signed rank sum test was used to compare the efficacy of short-term preoperative OCT treatment. RESULTS: OCT treatment (median time: 7.9 days, range: 3-16 days; median total dose: 1.8 mg, range: 0.9-4.2 mg) led to significant decrease in all patients' thyroid hormone levels (FT3 [nmol/L]: 8.33 [7.02, 12.29] to 4.67 [3.52, 5.37] [P = 0.008]; FT4 [pmol/L]: 25.36 [21.34, 28.99] to 16.66 [14.88, 21.49] [P = 0.016]; and TSH [µU/ml]: 5.80 [4.37, 6.78] to 0.57 [0.19, 1.24] [P = 0.008]). All the eight tumor specimens expressed high SSTR2 protein levels; 5/8 expressed high SSTR5, but 3/8 that expressed low SSTR5 presented a significantly higher TSH suppression rate (P = 0.036). Electron microscopy showed subcellular level impairments, including clumped nuclear chromatin and reduced cytoplasmic volume. Golgi complexes were observed in the OCT-treated TSHoma specimens. CONCLUSIONS: OCT can control hormone levels and damage the ultrastructure of tumor cells and organelles. Short-term response to OCT may be related to SSTR5 expression. Preoperative SST analog treatment for TSHoma could be considered as a combination therapy.

A Novel Invasive-Related Biomarker in Three Subtypes of Nonfunctioning Pituitary Adenomas.

OBJECTIVE: To identify biomarkers key to invasiveness of the 3 subtypes of nonfunctioning pituitary adenomas (NFPAs) and provide a guidance for therapeutic decision making and identification of potential adjuvant drugs. METHODS: Fifty NFPA tumor tissues obtained from transsphenoidal surgery were used in the study. Three invasive NFPAs and 4 noninvasive NFPAs were used for gene expression microarray analyses. In addition, there are 5 invasive NFPAs and 4 noninvasive NFPAs used for proteomic analyses. Invasive-related biomarkers were identified by bioinformatics analysis by integrating the transcriptomics and proteomics data sets. All 3 subtypes of NFPAs (null cell adenomas, oncocytomas, and gonadotroph adenomas) were used to validate differentially expressed candidate biomarkers by means of quantitative real-time reverse transcription polymerase chain reaction and Western blot. The level of EZR was downregulated in pituitary adenoma cell line GH3 to investigate the invasive effect of EZR on GH3 cells by using the RNA interference technique. RESULTS: Eight genes involved in the invasion function were found by bioinformatics analysis, and the EZR gene was identified as a novel invasive-related biomarker in the 3 subtypes of NFPAs. The expression level of EZR was found higher in terms of invasiveness than the noninvasive ones of the 3 subtypes of NFPAs. Moreover, the knockdown of EZR inhibited the invasion of GH3 cells in vitro. CONCLUSIONS: EZR is a novel biomarker in terms of invasion among the 3 subtypes of NFPAs, and it is a promising guide for therapeutic decision making as well.

Integrative proteomics and transcriptomics revealed that activation of the IL-6R/JAK2/STAT3/MMP9 signaling pathway is correlated with invasion of pituitary null cell adenomas.

Non-functioning pituitary adenomas (NFPAs) are a highly heterogeneous group, but few studies have explored the invasion mechanism of specific subtypes of NFPAs. The objective of this study was to investigate the differential molecular expression patterns and the critical biological signaling pathways involved in the invasion of pituitary null cell adenomas (PNCAs) through integrative proteomics and transcriptomics. A total of 1160 genes and 283 proteins were found to be differentially expressed in invasive and non-invasive PNCAs. The differentially expressed molecules related to invasion were enriched in 15 canonical signaling pathways, 15 clusters of diseases or biological functions and 5 upstream molecules. Among them, the majority of the differentially expressed molecules were found to be involved in transport of molecule, migration of cells and cell movement. Notably, IL-6 was a significantly activated upstream regulator, and the IL6R/JAK2/STAT3 cascade was found to play a critical role in acute phase response signaling, which was the most significant canonical signaling pathway. Furthermore, we validated the overexpression of IL-6R, JAK2, STAT3, p-STAT3 and MMP9 in invasive PNCAs. Our data suggest that overactivation of the IL-6R/JAK2/STAT3/MMP9 pathway is critical for the invasion of PNCAs.

Endoscopic treatment of suprasellar cysts without hydrocephalus.

OBJECTIVE At present, endoscopic treatment is advised as the first procedure in cases of suprasellar arachnoid cysts (SSCs) with hydrocephalus. However, the appropriate therapy for SSCs without hydrocephalus has not been fully determined yet because such cases are very rare and because it is usually difficult to perform the neuroendoscopic procedure in patients without ventriculomegaly given difficulties with ventricular cannulation and the narrow foramen of Monro. The purpose of this study was to find out the value of navigation-guided neuroendoscopic ventriculocystocisternostomy (VCC) for SSCs without lateral ventriculomegaly. METHODS Five consecutive patients with SSC without hydrocephalus were surgically treated using endoscopic fenestration (VCC) guided by navigation between March 2014 and November 2015. The surgical technique, success rate, and patient outcomes were assessed and compared with those from hydrocephalic patients managed in a similar fashion. RESULTS The small ventricles were successfully cannulated using navigational tracking, and the VCC was accomplished in all patients. There were no operative complications related to the endoscopic procedure. In all patients the SSC decreased in size and symptoms improved postoperatively (mean follow-up 10.4 months). CONCLUSIONS Endoscopic VCC can be performed as an effective, safe, and simple treatment option by using intraoperative image-based neuronavigation in SSC patients without hydrocephalus. The image-guided neuroendoscopic procedure improved the accuracy of the endoscopic approach and minimized brain trauma. The absence of hydrocephalus in patients with SSC may not be a contraindication to endoscopic treatment.

Treatment of Middle Cranial Fossa Arachnoid Cysts: A Systematic Review and Meta-Analysis.

OBJECTIVE: To review the literature and analyze the efficacy and safety of 3 surgical methods (neuroendoscopic fenestration, microsurgical fenestration, and cystoperitoneal shunting) for middle cranial fossa arachnoid cysts (MCFACs). METHODS: We searched MEDLINE, PubMed, and Cochrane Central electronic databases and collected studies of patients with MCFACs treated with 1 of 3 surgical methods. Eligible studies reported the rate of clinical symptoms improvement (RCSI), rate of cyst reduction (RCR), rate of total complications (RTC), rate of short-term complications (RSTC), rate of long-term complications (RLTC), and other parameters. RESULTS: Eighteen studies met the criteria. MCFACs were divided into 3 groups on the basis of surgical method: RCSI in group I (237 patients, neuroendoscopic fenestration) was 90% (95% confidence interval [CI]: 83%-95%); RCR: 76% (95% CI: 67%-84%); RTC: 28% (95% CI: 22%-34%); RSTC: 23% (95% CI: 17%-30%); and RLTC: 6% (95% CI: 3%-11%). RCSI in group II (144 patients, microsurgical fenestration) was 87% (95% CI: 75%-96%); RCR: 87% (95% CI: 70%-97%); RTC: 49% (95% CI: 30%-68%); RSTC: 44% (95% CI: 21%-68%); RLTC: 3% (95% CI: 0%-12%). RCSI in group III (93 patients, cystoperitoneal shunting) was 93% (95% CI: 66%-99%); RCR: 93% (95% CI: 66%-99%); RTC: 20% (95% CI: 5%-42%); RSTC: 10% (95% CI: 0%-31%); RLTC: 15% (95% CI: 9%-23%). RLTC differed significantly between the 3 groups (P = 0.005); RTC and RSTC between group I and group II (P = 0.002). CONCLUSIONS: All 3 surgical methods are effective for MCFACs, but considering safety, neuroendoscopic fenestration may be the best initial procedure.

Integrative proteomics and transcriptomics identify novel invasive-related biomarkers of non-functioning pituitary adenomas.

Non-functioning pituitary adenomas (NFPAs) are usually macroadenomas and display invasion into surrounding tissues. The treatment for invasive NFPAs is still challenging. This study describes the differential patterns of gene expression between invasive and non-invasive NFPAs and identifies novel biomarkers involved in invasion of NFPAs for diagnosis and treatment. Using gene microarray technology, we examined the gene expression profile and found 1160 differentially expressed messenger RNA (mRNA) between invasive and non-invasive NFPAs. Then, we examined the protein profile by liquid chromatography tandem mass spectrometry (LC-MS/MS) and found 433 differentially expressed proteins between invasive and non-invasive NFPAs. Subsequently, we integrated the proteomics and transcriptomics datasets and identified 29 common changed molecules. Through bioinformatics analysis using Ingenuity Pathway Analysis (IPA) software, we showed that the 29 molecules were enriched in 25 canonical signaling pathways, 25 molecular and cellular functions, and 2 networks. Eight genes were identified involved in the invasion function by the molecular and cellular functions analysis, including CAT, CLU, CHGA, EZR, KRT8, LIMA1, SH3GLB2 and SLC2A1. Furthermore, we validated the decreased CHGA expression and increased CLU expression in invasive NFPAs by qRT-PCR and Western blot. Our study demonstrated that integration of proteomics and transcriptomics could prove advantageous for accelerating tumor biomarker discovery and CHGA and CLU might be important novel biomarkers and therapeutic targets for invasion of NFPAs.

Anatomical partition of the clival region and adjacent structures via extended endoscopic endonasal approach.

OBJECTIVES: To explore the anatomy of the ventral clivus and adjacent structure in the endoscopic surgery through the anterior approach, particularly in accurate locating lesions in transnasal endoscopic surgery. PATIENTS AND METHODS: A total of 9 formalin-fixed adult cadaver heads were injected with red and blue latex to observe the arteries and veins, respectively. The relationships between various parts of internal carotid artery (ICA) and anatomic structures of clivus were investigated, followed by the measurement of the posterior pharyngeal wall, anterior wall and posterior wall of clivus, cerebral dura mater, subdural space and adjacent regions to determine their correlations, as well as the clivus and adjacent structures. RESULTS: The clivus structure was divided into the bone segment, the ICA segment and subdural segment for anatomic division according to the anatomic landmarks in the anatomic process. The clivus can be classified in a shape of '' with the ICA, including the middle superior region, middle inferior region, bilateral lateral superior and lateral inferior regions. CONCLUSION: The ICA is closely related to the ventral clivus and adjacent structure, which can be used as the basis of anatomic division via anterior approach.

PCSK9 regulates apoptosis in human neuroglioma u251 cells via mitochondrial signaling pathways.

Proprotein convertase subtilisin/kexin type 9 (PCSK9), belongs to a family of proprotein convertases (PCs), encodes a neural apoptosis-regulated convertase 1. However, the precise role of PCSK9 during glioma cells apoptosis has not been reported. Therefore, we examined the effects of knockdown and overexpression of PCSK9 on apoptosis of human neuroglioma U251 cells, and investigated the underlying mechanisms of apoptosis. We found that PCSK9 regulated cells proliferation as determined by CCK-8 and Hoechst staining analysis. In addition, western blot results showed that PCSK9 siRNA promote apoptosis via activation of caspase-3 and down-regulation of the anti-apoptotic proteins, XIAP and p-Akt, while PCSK9 overexpression inhibited apoptosis. Moreover, PCSK9 siRNA improved the ratio of Bax/Bcl-2 which leads to the release of cytochrome c, while PCSK9 overexpression decreased it. Taken together, these data demonstrate that PCSK9 may regulate apoptosis through mitochondrial pathway and is expected to be a promising therapeutic strategy for the malignant glioma.

Endoscopic approach to the trigeminal nerve: an anatomic study.

OBJECTIVE: To describe an endoscopic perspective of the surgical anatomy of the trigeminal nerve. METHODS: Nine adult cadaveric heads were dissected endoscopically. RESULTS: Opening the pterygopalatine fossa is important because many key anatomical structures (V2, pterygopalatine ganglion, vidian nerve) can be identified and traced to other areas of the trigeminal nerve. From the pterygopalatine ganglion, the maxillary nerve and vidian nerve can be identified, and they can be traced to the gasserian ganglion and internal carotid artery. An anteromedial maxillectomy increases the angle of approach from the contralateral nares due to an increase in diameter of the piriform aperture, and provides excellent access to the mandibular nerve, the petrous carotid, and the cochlea. CONCLUSIONS: Identification of key anatomical structures in the pterygopalatine fossa can be used to identify other areas of the trigeminal nerve, and an anteromedial maxillectomy is necessary to expose the ipsilateral mandibular nerve and contralateral cranial level of the trigeminal nerve.