Recycling of SLC38A1 to the plasma membrane by DSCR3 promotes acquired temozolomide resistance in glioblastoma.

PURPOSE: Glioblastoma multiforme (GBM) is a primary brain tumor with devastating prognosis. Although the O6-methylguanine-DNA methyltransferase (MGMT) leads to inherent temozolomide (TMZ) resistance, approximately half of GBMs were sufficient to confer acquired TMZ resistance, which express low levels of MGMT. The purpose of this study was to investigate the underlying mechanisms of the acquired TMZ resistance in MGMT-deficient GBM. METHODS: The function of Down syndrome critical region protein 3 (DSCR3) on MGMT-deficient GBM was investigated in vitro and in an orthotopic brain tumor model in mice. Purification of plasma membrane proteins by membrane-cytoplasmic separation and subsequent label free-based quantitative proteomics were used to identified potential protein partners for DSCR3. Immunofluorescence was performed to show the reverse transport of solute carrier family 38 member 1 (SLC38A1) mediated by DSCR3. RESULTS: DSCR3 is upregulated in MGMT-deficient GBM cells during TMZ treatment. Both DSCR3 and SLC38A1 were highly expressed in recurrent GBM patients. Silencing DSCR3 or SLC38A1 expression can increase TMZ sensitivity in MGMT-deficient GBM cells. Combination of proteomics and in vitro experiments show that DSCR3 directly binds internalized SLC38A1 to mediate its sorting into recycling pathway, which maintains the abundance on plasma membrane and enhances uptake of glutamine in MGMT-deficient GBM cells. CONCLUSIONS: DSCR3 is a crucial regulator of acquired TMZ resistance in MGMT-deficient GBM. The DSCR3-dependent recycling of SLC38A1 maintains its abundance on plasma membrane, leading to tumor progression and acquired TMZ resistance in MGMT-deficient GBM.

Establishing a papillary craniopharyngioma cell line by SV40LT-mediated immortalization.

BACKGROUND: Craniopharyngioma represents a troublesome tumor of the intracranial sellar region. There are currently no available well-characterized craniopharyngioma cell lines. This lack of reliable, immortal cell lines is a major reason for the slow progress in fundamental research related to craniopharyngioma. METHODS: We describe the development of an immortal papillary craniopharyngioma (PCP) cell line by transfecting primary PCP cells with the pLenti-simian virus 40 large T antigen(SV40LT). RESULTS: Three clones have been cultured for more than 14 months so far, while non-transfected cells ceased proliferation within three months of isolation. The established immortal PCP cell lines were identified to have BRAFV600E mutations, while no mutations in tumor suppressor genes were found in primary cells or immortal cells. Immortal cells had higher proliferation rates and formed tumors when implanted in the bran of nude mice. BRAF inhibition in immortal PCP cells altered cell morphology, inhibited cell proliferation and promoted apoptosis. CONCLUSION: We successfully developed PCP cell lines by SV40LT-mediated immortalization. These cell lines represent a powerful tool for fundamental and therapeutical studies on craniopharyngioma.

Periostin: a novel prognostic predictor for meningiomas.

The expression and role of periostin in meningiomas remains unknown. Tissue specimens of 175 convexity meningiomas were immunohistochemically examined with antibodies against periostin and Ki67. The expression levels of periostin and Ki67 were compared among different WHO groups. The role of periostin and Ki67 in postoperative prognosis of meningiomas was also analyzed. Negative (-) expression of Ki67 was observed in 101 (57.7 %) cases of all the surgical tissue samples. The Ki67 expressions differed significantly among the WHO groups (P < 0.001) and correlated positively with the WHO grade (r = 0.673, P < 0.001). Low/negative staining of periostin was observed in 116 (66.3 %) cases. The periostin expressions differed significantly among the WHO groups (P < 0.001). Periostin expression correlated positively with the WHO grade (r = 0.742, P < 0.001). There was a positive correlation between Ki67 expression and periostin (r = 0.513, P < 0.001). Both Ki67 expression and periostin expression was found statistically different between brain invasion tumor and non-invasion tumor (p < 0.001). The recurrence rate and PFS rate in both varied Ki67 expression groups and periostin expression groups was statistically different (P < 0.001). The survival time and PFS time in both varied Ki67 expression groups and periostin expression groups was also statistically different (P < 0.001). Periostin was expressed in tumor stroma of meningiomas. Both periostin and Ki67 may behave as a maker in predicting the grade and prognosis in meningiomas. Drugs that targets periostin aims at reducing invasion of meningioma patients should be further researched.

Tumor cells forming sinusoids connected to vasculature are involved in hemorrhage of pineal choriocarcinoma.

Intratumor hemorrhage is a poor prognostic factor in pineal choriocarcinoma (PCCC). The aim of this study was to understand the relationship of tumor cells to the blood vessels to gain insights into the formation of intratumor hemorrhage in PCCC. The clinical data indicated that total tumor removal by surgical procedures followed immediately by radiotherapy and chemotherapy improved the prognosis in PCCC. The PCCC tissues removed from the patients were examined by histology and immunohistochemistry. Hematoxylin and eosin staining showed that the tumor stroma mainly consists of hemorrhagic tissues with tumor cells scattered inside. The pattern of distribution suggests that the tumor cells were possibly flushed and compressed by the bleeding. The tumor cells tended to form sinusoids that lacked CD34, but laminin expression provided evidence of vasculogenic mimicry. Interestingly, CD34-positive blood vessels were found connected to these sinusoids, suggesting that blood may flow from the tumor vasculature to the sinusoids. This may subsequently cause the enlargement of the sinusoids, blood clotting, the widening of the blood lakes, and eventually extensive hemorrhagic necrosis. Our study identified the key features of the PCCC vasculature. The findings add to the previous understanding of the formation of vascular channels, blood lakes, and extensive hemorrhagic necrosis. The intimate connections between the tumor-formed sinusoids and the blood vessels might be a major cause of severe hemorrhage in PCCC. The new information may be useful for the development of treatment strategies for managing PCCC.

Relationships of LDLR genetic polymorphisms with cerebral infarction: a meta-analysis.

This meta-analysis was undertaken to identify the relationships between genetic polymorphisms in the LDLR gene and the risk of cerebral infarction. The Web of Science (1945-2013), the Cochrane Library Database (Issue 12, 2013), PubMed (1966-2013), EMBASE (1980-2013), CINAHL (1982-2013) and the Chinese Biomedical Database (CBM) (1982-2013) were searched for relevant articles without language restrictions. Meta-analysis was conducted using the STATA 12.0 software. Crude odds ratios (OR) with their corresponding 95% confidence interval (CI) were calculated. Eight case-control studies with a total of 4,655 patients with cerebral infarction and 15,920 healthy control subjects were included in our meta-analysis. Five common polymorphisms in the LDLR gene were evaluated, including rs11669576 A > T, rs1433099 C > T, rs5925 C > T, rs688 C > T, rs1122608 T > G in the LDLR gene. The results of this meta-analysis revealed that cerebral infarction patients had a higher frequency of LDLR genetic polymorphisms than that of healthy controls (allele model: OR 1.17, 95% CI 1.05-1.30, P = 0.004; dominant model: OR 1.18, 95% CI 1.05-1.33, P = 0.007; homozygous model: OR 1.50, 95% CI 1.03-2.16, P = 0.032; respectively), especially for the rs11669576 A > T, rs1433099 C > T and rs5925 C > T polymorphisms. Among different ethnic subgroups, the results demonstrated positive correlations between LDLR genetic polymorphisms and an increased risk of cerebral infarction among both Asians and Caucasians under the allele and dominant models (all P < 0.05). Our findings indicate that LDLR genetic polymorphisms may be strongly involved in the pathogenesis of cerebral infarction, especially the rs11669576 A > T, rs1433099 C > T, rs5925 C > T polymorphisms.

Stereotactic neurosurgical technique and electrophysiological study in ablating the ventromedial shell of the nucleus accumbens.

OBJECTIVE: To describe in as much detail as possible the method for ablating the ventromedial shell of the nucleus accumbens (NAc) and investigate the efficacy and safety of the ablation treatment. METHODS: Sixty-five patients with drug addictions received operations within the time frame from 2004 to 2009. The ablation targets were located in the bilateral medial posterior inferior shell of the NAc. Intraoperative electrophysiological monitoring was performed. RESULTS: Tissue impedance in the shell of the NAc varied from 185 to 355 Ω. When stimulated with a low frequency (2 Hz) and a voltage above 3 V, 57 out of 65 (87.7%) patients experienced slight throbbing sensations. During the lesion procedure, fever was detected on the head and face of 59 patients (90.8%), the heart rate decreased in 19 cases (29.2%), and restlessness, irritability and hyperalgia were noted for all patients. Among the 65 patients, 52 (80%) no longer experienced a psychological craving for the drug. CONCLUSIONS: The shell of the NAc may be a promising surgical target for psychosurgery. Electrophysiological recordings revealed that the shell is indeed an appropriate structure.

Topographic variations of the optic chiasm and the pituitary stalk: a morphometric study based on midsagittal T2-weighted MR images.

PURPOSE: This study was conducted to characterize topographic variations of the optic chiasm (OC) and the pituitary stalk (PS) in situ based on MR images. METHODS: Normal T2-weighted midsagittal MR images were obtained in 157 children and 323 adults. The height of OC (PC) and the inclination angle of PS (PS-AP angle) were measured in each case. All chiasms were classified into prefixed, normal and postfixed types, and low, medium and high types, respectively. All stalks were performed classification (prefixed, centered and postfixed PS) and grading (Grade 1-3 according to the relationship between PS and the dorsum sellae), respectively. RESULTS: PC averaged 4.33 ± 1.59 mm. Adults had a greater PC (P = 0.023) than children. There were 80 (16.7 %) prefixed, 354 (73.8 %) normal and 46 (9.6 %) postfixed chiasms, and 112 (23.3 %), 295 (61.5 %) and 73 (15.2 %) cases with low, medium and high OC, respectively. High OC was more frequent in adults than in children (P = 0.001). The mean PS-AP angle of the whole group was 59.47 ± 8.62º. Children had a greater PS-AP angle than adults (P = 0.012). Adults had a greater percentage of postfixed (P = 0.000) and grade 3 (P = 0.000) PS than children, whereas centered (P = 0.002) and grade 1 (P = 0.001) PS were more prevalent in children than in adults. CONCLUSIONS: The classifications of OC and PS based on MR images reflect the topographic variations of their real position in vivo. It would be helpful to identify and characterize the anomalies involving OC and PS and understand the anatomical and physiological influence in pathological situations.

[Operative strategies for bilateral brain contusion and laceration].

OBJECTIVE: To explore the operative strategies for bilateral brain contusion and laceration and evaluate their clinical significance. METHODS: Based on the clinical manifestations, computed tomography (CT) and intracranial pressure (ICP), different operative strategies were applied to 25 cases of bilateral brain contusion and laceration. The strategies were classified into 6 types according to the principles of decompression and brain protection.All cases received routine treatments at neurosurgical intensive care unit (ICU) ward. And the occurrences of operative complications and 6-month Glasgow outcome scale (GOS) were statistically analyzed. RESULTS: Type 1:4 cases of unilateral decompressive craniectomy without resection of contusion focus; Type 2:8 cases of unilateral decompressive craniectomy with resection of bilateral contusion focus; Type 3:5 cases of bilateral decompressive craniectomy with resection of unilateral brain contusion; Type 4:5 cases of bilateral decompressive craniectomy; Type 5:1 case of bilateral brain contusion resection; Type 6:2 cases of bilateral decompressive craniectomy and brain contusion resection.Postoperative complications such as epilepsy, expanding contusion foci, brain infarction, encephalocele, incisional CSF leakage, intracranial infection, subdural hydroma and hydrocephalus were rare. The 6-month GOS revealed 6 cases of good outcome (n = 6), moderate disability (n = 8), severe disability (n = 3) and vegetative status (n = 5) and death (n = 3). CONCLUSION: Different operative strategies may be applied for severe brain contusion and laceration according to their clinical manifestations, CT findings and ICP values. And the efficacies are improved by operative strategies based on the principles of ICP control, prevention of secondary injury and brain function preservation.

[Expression pattern of inflammatory cytokines at various inflammatory levels of adamantinomatous craniopharyngioma].

OBJECTIVE: To explore the expression pattern of inflammatory cytokines at various inflammatory levels of adamantinomatous craniopharyngioma by cytokine antibody array. METHODS: The inflammatory levels of adamantinomatous craniopharyngioma were evaluated on the basis of the number of inflammatory cells at the interface of tumor and normal tissues. And the expression of inflammatory cytokines was examined at various inflammatory levels of adamantinomatous craniopharyngioma by inflammatory cytokine antibody array and the results were verified by Western blot. RESULTS: Compared with the mild inflammatory group, the levels of inflammatory cytokines of severe inflammatory group markedly increased, including pro-inflammatory cytokines, chemokines and cytokine receptors. CONCLUSION: Antibody array demonstrates a significant change in cytokine profiles in adamantinomatous craniopharyngioma with severe inflammation, as compared with those with mild inflammation.

Epithelial-mesenchymal transition and clinicopathological correlation in craniopharyngioma.

AIMS: To assess the immunophenotypic changes associated with epithelial-mesenchymal transition (EMT) in craniopharyngioma, especially at the tumour invasive front, and to correlate the findings with clinicopathological features and patient outcomes. METHODS AND RESULTS: Forty-two craniopharyngiomas were investigated for the presence of EMT markers (vimentin, E-cadherin and ß-catenin) by immunohistochemistry and western blot. The relationships between expression of these markers and various clinicopathological indicators and clinical outcomes of the tumours were analysed. There were statistically significant differences in the expression of vimentin and E-cadherin-ß-catenin between adamantinomatous and papillary variants. The expression of vimentin and E-cadherin (but not that of ß-catenin) in whole tumour sections was associated with tumour recurrence, and with postoperative weight and hypothalamic disturbances; the expression of vimentin and E-cadherin-ß-catenin at the tumour invasive front was also associated with tumour recurrence, postoperative weight, and hypothalamic disturbances. The results from western blotting closely matched those of immunohistochemistry. CONCLUSION: Our study demonstrates, for the first time, the potential prognostic implications of vimentin, E-cadherin and ß-catenin expression in craniopharyngiomas. EMT may represent a crucial mechanism in the progression of craniopharyngiomas.

Anatomical and histological study of Liliequist's membrane: with emphasis on its nature and lateral attachments.

PURPOSE: In previous studies, some disagreements regarding the nature (inner or outer arachnoid membrane) and lateral boundaries (temporal uncus or tentorial edge) of Liliequist's membrane remain. The aim was to clarify whether Liliequist's membrane is an inner or outer arachnoid membrane, and the distribution of Liliequist's membrane with emphasis on its lateral attachments. METHODS: Liliequist's membrane was investigated by microsurgical dissection in 24 formalin-fixed adult cadaver heads and by histological sections of sellar-suprasellar specimens from another four formalin-fixed adult cadaver heads. RESULTS: The results obtained in the present study indicated that 1) Liliequist's membrane arises from the basal arachnoid membrane and has two components: a basal part comprising a folding inner layer of the arachnoid mater and an attaching part consisting of accumulated arachnoid trabeculae; 2) similar histological features are also present in other inner arachnoid membranes with attachments on basal arachnoid membrane, demonstrating Liliequist's membrane is an inner arachnoid membrane; 3) laterally, Liliequist's membrane attaches to the anterior tentorial edge constantly and to the mesial temporal uncus in more than half; 4) the oculomotor nerve courses above Liliequist's membrane and is fixed on Liliequist's membrane by the oculomotor membrane, which can also attach on temporal uncus and should be differentiated from the true temporal attachments of Liliequist's membrane. CONCLUSION: Liliequist's membrane is an inner rather than outer arachnoid membrane. Understanding of its individual variation and topographic relationships with surrounding neurovascular and arachnoid structures is important for neurosurgical practice.

[Feasibility of a novel material for the reconstruction of skull base in a canine].

OBJECTIVE: To explore the therapeutic efficacy of a novel complex material of shape-memory alloy brace and artificial dura (nitinol brace and NormalGEN) for the reconstruction of skull base in a canine model with lateral media skull base defect. METHODS: The complex of nitinol brace and NormalGEN was developed with corresponding apparatus. A common adult dog model with lateral media skull base defect was established and then reconstructed with the complex. At Month 3 post-operation, cranial lateral radiographic projection, three-dimensional reconstruction of computer tomography, 1.5T magnetic resonance imaging and histopathological examination were detected. RESULTS: Five animal models and cranial reconstructions were made. All survived without any complication, such as leakage of cerebrospinal fluid, local tissue eminence and neurological function defect. The imaging detection showed that nitinol brace was distinct and satisfactorily positioned without shift and artifact. And histopathological examination showed that granulation tissue substituted NormalGEN and grew around the brace with numerous fibroblasts. CONCLUSION: The complex of shape-memory alloy brace and artificial is suitable for the reconstruction of skull base on dog model with lateral media skull base defect.

Incidence and Possible Predictors of Sodium Disturbance After Craniopharyngioma Resection Based on QST Classification.

OBJECTIVE: Serum sodium abnormalities are one of the most common manifestations after radical craniopharyngioma (CP) excision. The aim of this study was to report the incidence and possible predictors of serum sodium disturbance and explore features of sodium destabilization manifestation among QST classification results after CP resection. METHODS: A retrospective analysis was performed of clinical, biochemical, radiologic, and operative data for 134 successive patients who underwent primary CP removal between September 2016 and March 2018. Univariate and multivariate analyses were conducted to determine predictors. RESULTS: Sixty patients (44.8%) experienced hyponatremia and 67 patients (50%) hypernatremia; the median time of onset was 6 days and the first day after surgery, respectively. The incidence, onset, severity, and type of sodium disturbance among different types of CP differed significantly based on statistical tests (P < 0.05). Sodium disturbance was more common and severe in patients with type T tumors (P < 0.05). Age, tumor type, and preoperative diabetes insipidus were independent prognostic factors for obvious disorders of serum sodium. CONCLUSIONS: Hyponatremia/hypernatremia is common after primary CP resection. The site of tumor origin has a direct effect on the growth pattern of CP, which may serve as a useful index for anticipating sodium perturbation after surgery. The level of sodium in children and patients with type T tumors, preoperative diabetes insipidus should be monitored closely throughout hospitalization.

[Clinical study of pineal region tumors: experience with 132 patients].

OBJECTIVE: To review the clinical manifestations, imaging, tumor markers, treatment methods, pathology results and clinical curative effects of pineal region tumors and to evaluate the characteristics and intervention strategies for those tumors. METHODS: The clinicopathological data of 132 patients with pineal region tumor treated in our department between January 2000 and May 2008 were retrospectively studied. RESULTS: A moderate predominance in males was presented. The clinical manifestations of the disease included increased intracranial pressure and ocular movement impairment. There were some features but no regularity and specific appearance on imaging including CT and MRI. 88.6% of patients associated with hydrocephalus. A high serum level of alpha-fetoprotein (AFP) was presented in 14 cases and high HCG in 9 cases. Eighteen cases received direct radiation therapy and 7 had radiotherapy post biopsy. 107 cases were treated surgically and 63 cases received postoperative adjuvant treatment. 114 cases had pathology results including 56 germ cell tumors. The patients were followed up for 12 approximately 132 months. Recurrence developed in 23 cases and 12 cases died. The 5-year survival rate was 89.3%. CONCLUSION: Pineal region tumors are often associated with hydrocephalus and this makes preoperative diagnosis difficult. Imaging examination may help diagnosis but less specific. Germ cell tumors may diagnosed by some tumor markers. Radiation therapy is the choice of treatment for pure germinomas. Other types of pineal region tumors should receive surgical treatment. Postoperative adjuvant treatment based on pathology can provide a good prognosis in pineal region tumor.

Feasibility of primary human cell cultures as a model for adamantinomatous craniopharyngioma research: Evidence from RNA-Seq analysis.

Adamantinomatous craniopharyngioma (ACP) is a benign epithelial tumor of the sellar region. Whether primary human cell cultures can be used as a stable research model has yet to be determined. The characteristics of three cultured craniopharyngioma primary cell (CPC) lines were identified using immunofluorescence. The culture duration for each CPC line was 10, 20 and 30 days. Cell lines and paired parental tumor tissues were subsequently analyzed using transcriptome sequencing (RNA-Seq). Transcriptomic differences between ACP tissues and CPC lines were compared. CPCs maintained the original epithelial lineage markers, including pan-cytokeratin and epithelial cell adhesion molecule. However, the Pearson's correlation coefficient of transcriptomes between each pair of CPC lines and ACP tissues decreased from 0.657 (cultured for 10 days) to 0.61 (cultured for 20 days) and further to 0.547 (cultured for 30 days). The number of differentially expressed genes between ACP tissues and CPCs was increased from 1,247 (cultured for 10 days) to 1,643 (cultured for 20 days) and then to 1,949 (cultured for 30 days). The results of Gene Set Enrichment Analysis demonstrated that the diversity of gene sets increased with longer culture time. Significant differences in the majority of signature gene sets were not observed between ACP tissues and CPCs, with the exception of keratinization phenotype [normalized enrichment score (NES)=-2.02, false discovery rate (FDR)=0.0038] and epithelial cell phenotype (NES=-1.82, FDR=0.032). Cell proliferation (NES=1.78, FDR=0.028) and mitosis (NES=1.93, FDR=0.012) were enhanced in CPCs. Therefore, primary human cell cultures can be used as a suitable research platform for ACP, however further experiments are required.

Identification of tumor stem-like cells in admanatimomatous craniopharyngioma and determination of these cells' pathological significance.

OBJECTIVE: Nuclear ß-catenin, a hallmark of active canonical Wnt signaling, can be histologically detected in a subset of cells and cell clusters in up to 94% of adamantinomatous craniopharyngioma (ACP) samples. However, it is unclear whether nuclear ß-catenin-containing cells within human ACPs possess the characteristics of tumor stem cells, and it is unknown what role these cells have in ACP. METHODS: Primary ACP cells were cultured from 12 human ACP samples. Adamantinomatous CP stem cell-like cells (CSLCs) showing CD44 positivity were isolated from the cultured primary ACP cells by performing magnetic-activated cell sorting. The tumor sphere formation, cell cycle distribution, stemness marker expression, and multidifferentiation potential of the CD44- cells and the CSLCs were analyzed. RESULTS: Compared with the CD44- cells, the cultured human CSLCs formed tumor spheres and expressed CD44 and CD133; moreover, these cells demonstrated nuclear translocation of ß-catenin. In addition, the CSLCs demonstrated osteogenic and adipogenic differentiation capacities compared with the CD44- cells. The CSLCs also displayed the capacity for tumor initiation in human-mouse xenografts. CONCLUSIONS: These results indicate that CSLCs play an important role in ACP development, calcification, and cystic degeneration.

Endoplasmic reticulum stress induces apoptosis of arginine vasopressin neurons in central diabetes insipidus via PI3K/Akt pathway.

AIMS: Central diabetes insipidus (CDI), a typical complication caused by pituitary stalk injury, often occurs after surgery, trauma, or tumor compression around hypothalamic structures such as the pituitary stalk and optic chiasma. CDI is linked to decreased arginine vasopressin (AVP) neurons in the hypothalamic supraoptic nucleus and paraventricular nucleus, along with a deficit in circulating AVP and oxytocin. However, little has been elucidated about the changes in AVP neurons in CDI. Hence, our study was designed to understand the role of several pathophysiologic changes such as endoplasmic reticulum (ER) stress and apoptosis of AVP neurons in CDI. METHODS: In a novel pituitary stalk electric lesion (PEL) model to mimic CDI, immunofluorescence and immunoblotting were used to understand the underlying regulatory mechanisms. RESULTS: We reported that in CDI condition, generated by PEL, ER stress induced apoptosis of AVP neurons via activation of the PI3K/Akt and ERK pathways. Furthermore, application of N-acetylcysteine protected hypothalamic AVP neurons from ER stress-induced apoptosis through blocking the PI3K/Akt and ERK pathways. CONCLUSION: Our findings showed that AVP neurons underwent apoptosis induced by ER stress, and ER stress might play a vital role in CDI condition through the PI3K/Akt and ERK pathways.

Pathological Relationship Between Adamantinomatous Craniopharyngioma and Adjacent Structures Based on QST Classification.

The aim of this study was to clarify pathological and anatomical relationships between adamantinomatous craniopharyngiomas (ACP) and their surrounding structures. We previously established a QST classification scheme based on the apparent anatomic origin of the tumors. According to this classification, 13 type Q tumors, 6 type S tumors, and 42 type T ACPs were analyzed. Type Q tumors, which are most likely to involve the pituitary gland, did not invade the area of contact with the adenohypophysis. Instead, tumor invasion was observed in areas where the tumor contacted the neurohypophysis. Type S tumors primarily involved the pituitary stalk; the arachnoid remained present between these tumors and normal structures. Type T tumors were located beneath the basal arachnoid membrane and outside the pia mater. The pia mater was disrupted and finger-like invasions were found in the neural layer of the third ventricle floor along the invasive front. Tumors were never observed to break through the ependymal layer of the third ventricle. The QST classification has important implications for understanding the growth pattern of tumors and can be used to guide surgical procedures.

[Characteristics of collateral circulation in adult moyamoya disease based on modified Suzuki staging].

OBJECTIVE: To investigate the characteristics of collateral circulation in adult moyamoya disease (MMD). METHODS: The clinical data were collected from all adult patients with MMD undergoing digital subtractive angiography (DSA) in our department from 2006 to 2016. Based on the imaging findings, the patients were divided into ischemia group and bleeding group. A double-blind analysis was conducted of the CT or magnetic resonance imaging findings and the severity of the disease was graded using the modified Suzuki score (mSS). We classified the anastomotic networks in MMD into the superficial meningeal type and deep parenchymal type. The superficial meningeal type was further classified into the leptomeningeal and the durocortical networks, and the deep parenchymal networks into subependymal networks and the inner striatal and inner thalamic networks. RESULTS: No significant difference was found in the distribution of mSS scores between the hemorrhage group and the ischemic group (Χ2=5.812, v=5, P=0.325), but the posterior communicating artery and internal carotid artery diameter ratio (Pcom/ICA ratio) was significantly greater in the hemorrhage group (t=2.119, v=108, P=0.036). The Pcom/ICA ratio differed significantly among the groups with different mSS scores (f=8.924, P=0.00), higher in groups with mSS scores of 3, 4 and 5. The incidence of anterior choroidal artery dilation differed significantly between hemorrhage and ischemic groups (Χ2=11.79, P=0.001). The incidences of durocortical networks (Χ2=0.327, P=0.567) and subependymal networks (Χ2=0.011, P=0.917) were comparable between hemorrhage group and ischemic groups, but the incidence of leptomeningeal networks (P=0.018) and inner striatal and inner thalamic networks (Χ2=7.551, P=0.006) differed significantly between the two groups. CONCLUSION: The collateral circulation vascular system is an important component of cerebral blood flow in MMD patients and varies from patient to patient. Patients with MMD exhibit increased Pcom/ICA ratio with abnormal expansion of the anterior choroidal artery, and the leptomeningeal networks and the inner striatal and inner thalamic networks are independent risk factors for cerebral hemorrhage.

miR-519a enhances chemosensitivity and promotes autophagy in glioblastoma by targeting STAT3/Bcl2 signaling pathway.

BACKGROUND: Chemoresistance to temozolomide (TMZ) is a major challenge in the treatment of glioblastoma (GBM). We previously found that miR-519a functions as a tumor suppressor in glioma by targeting the signal transducer and activator of transcription 3 (STAT3)-mediated autophagy oncogenic pathway. Here, we investigated the effects of miR-519a on TMZ chemosensitivity and autophagy in GBM cells. Furthermore, the underlying molecular mechanisms and signaling pathways were explored. METHODS: In the present study, two stable TMZ-resistant GBM cell lines were successfully generated by exposure of parental cells to a gradually increasing TMZ concentration. After transfecting U87-MG/TMZ and U87-MG cells with miR-519a mimic or inhibitor, a series of biochemical assays such as MTT, apoptosis, and colony formation were performed to determine the chemosensitive response to TMZ. The autophagy levels in GBM cells were detected by transmission electron microscopy, LC3B protein immunofluorescence, and Western blotting analysis. Stable knockdown and overexpression of miR-519a in GBM cells were established using lentivirus. A xenograft nude mouse model and in situ brain model were used to examine the in vivo effects of miR-519a. Tumor tissue samples were collected from 48 patients with GBM and were used to assess the relationship between miR-519a and STAT3 expression. RESULTS: TMZ treatment significantly upregulated miR-519a in U87-MG cells but not in U87-MG/TMZ cells. Moreover, the expression of miR-519a and baseline autophagy levels was lower in U87-MG/TMZ cells as compared to U87-MG cells. miR-519a dramatically enhanced TMZ-induced autophagy and apoptotic cell death in U87-MG/TMZ cells, while inhibition of miR-519a promoted TMZ resistance and reduced TMZ-induced autophagy in U87-MG cells. Furthermore, miR-519a induced autophagy through modification of STAT3 expression. The in vivo results showed that miR-519a can enhance apoptosis and sensitized GBM to TMZ treatment by promoting autophagy and targeting the STAT3/Bcl-2/Beclin-1 pathway. In human GBM tissues, we found an inverse correlation between miR-519a and STAT3 expression. CONCLUSIONS: Our results suggested that miR-519a increased the sensitivity of GBM cells to TMZ therapy. The positive effects of miR-519a may be mediated through autophagy. In addition, miR-519a overexpression can induce autophagy by inhibiting STAT3/Bcl-2 pathway. Therefore, a combination of miR-519a and TMZ may represent an effective therapeutic strategy in GBM.