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31.
Glioblastoma multiforme (GBM) is the commonest primary malignant neoplasm of the CNS. Usually, patients present with seizures and headache but in the elderly, confusion and generalised cognitive decline are more frequently the initial features. Multiple cranial nerve lesions as a manifestation of leptomeningeal meningitis is a rare presentation of GBM. The diagnosis is not often suggestive on either brain computed tomography (CT) or magnetic resonance imaging (MRI) and is usually confirmed by cerebrospinal fluid (CSF) cytology or histology. We describe the case of an 80-year-old man, who presented with multiple cranial nerve palsies and confusion secondary to leptomeningeal gliomatosis, in whom GBM was detected along the intra-ventricular lining of the left lateral ventricle at ventriculoscopy, in the absence of a distinct parenchymal lesion.  相似文献   
32.
阿霉素纳米粒对颅内移植G422小鼠的化疗实验研究   总被引:2,自引:1,他引:2  
目的:观察阿霉素纳米粒对颅内移植G422胶质母细胞瘤小鼠化疗后的生存期变化及病理改变,评估阿霉素纳米粒对胶质母细胞瘤的化疗效果。方法:将G422胶质母细胞瘤细胞移植入86只昆明小鼠脑白质中建模,然后随机分为6组,分别是大剂量阿霉素纳米粒(3×2.5 mg.kg-1)、中剂量阿霉素纳米粒(3×1.5 mg.kg-1)、小剂量阿霉素纳米粒(3×1.0 mg.kg-1)、空白纳米粒(3×2.5 mg.kg-1)、阿霉素生理盐水(3×2.5 mg.kg-1)和不予任何治疗的控制组。移植后第2、5、8天由尾静脉给药。肿瘤移植后第10天进行流式细胞仪、组织病理学检查。结果:与同等剂量的阿霉素生理盐水组相比,大剂量阿霉素纳米粒组生存期显著延长。各个剂量的阿霉素纳米粒组化疗效果与剂量呈正相关。组织病理学检查证实大剂量阿霉素纳米粒组肿瘤体积最小,肿瘤边缘清楚,未发现肿瘤细胞浸润,而阿霉素生理盐水组的脑肿瘤边缘不清楚,肿瘤呈浸润性生长。结论:阿霉素纳米粒可以作为治疗人类胶质母细胞瘤潜在的化疗药物。  相似文献   
33.
Development of necrosis is a characteristic feature of glioblastoma but its pathogenesis remains poorly understood. The process of poly(ADP-ribosyl)ation in response to DNA damage is mediated by poly(ADP-ribose) polymerase (PARP) and results in NAD+ depletion. The consequent ATP and energy depletion may result in cell necrosis. Therefore PARP activation is a potential candidate for a regulatory role in the pathogenesis of necrosis in glioblastoma. This study investigated whether there might be a relationship between both PARP expression and poly(ADP-ribosyl)ation, and necrosis in glioblastoma. The pattern of expression of PARP and of poly(ADP-ribose) groups in an archival series of glioblastoma was examined using immunohistochemistry. These parameters were also studied in multicellular tumour spheroids, derived from human glioma cell lines in which central necrosis develops with increasing spheroid diameter. Poly(ADP-ribose) groups were expressed in peri-necrotic tumour cells in glioblastoma. In the spheroid model poly(ADP-ribosyl)ation was seen centrally in pre-necrotic and necrotic cells with increasing spheroid diameter. PARP was widely expressed in viable tumour cells in the glioblastoma sections. In the spheroids, PARP expression, which was initially diffuse, became confined to the outer proliferative zone with increasing diameter. The pattern of expression of poly(ADP-ribose) groups in the spheroids and in glioblastoma raises the possibility that poly(ADP-ribosyl)ation may play a role in the development of necrosis in glioma. The high basal PARP expression in both glioblastoma and the spheroids suggests that this enzyme may have additional roles in glioma cell biology.  相似文献   
34.
目的 探讨吡格列酮(PGZ)对人神经胶质瘤细胞株SNB19增殖和凋亡的影响及其机制。方法 用MTT、流式细胞仪、Tunel和Western blot分析技术。结果 吡格列酮能够抑制SNB19细胞增殖和诱导其凋亡,同时伴有Bax表达的增高和pRb、Bcl-2表达的降低。结论 PGZ能够在体外抑制胶质瘤SNB19细胞的生长并诱导其凋亡,提示PGZ有可能成为一种新的治疗胶质瘤药物。  相似文献   
35.
Quaking (QKI) is a tumor-suppressor gene encoding a conserved RNA-binding protein, whose expression is downregulated in several solid tumors. Here we report that QKI plays an important role in the immune response and suppression of leukemogenesis. We show that the expression of Qki is reduced in lipopolysaccharide (LPS)-challenged macrophages, suggesting that Qki is a key regulator of LPS signaling pathway. Furthermore, LPS-induced downregulation of Qki expression is miR-155-dependent. Qki overexpression impairs LPS-induced phosphorylation of JNK and particularly p38 MAPKs, in addition to increasing the production of anti-inflammatory cytokine IL-10. In contrast, Qki ablation decreases Fas expression and the rate of Caspase3/7 activity, while increasing the levels of IL-1α, IL-1β and IL-6, and p38 phosphorylation. Similarly, the p38 pathway is also a target of QKI activity in chronic lymphocytic leukemia (CLL)-derived MEC2 cells. Finally, B-CLL patients show lower levels of QKI expression compared with B cells from healthy donor, and Qki is similarily downregulated with the progression of leukemia in Eμ-miR-155 transgenic mice. Altogether, these data implicate QKI in the pathophysiology of inflammation and oncogenesis where miR-155 is involved.  相似文献   
36.
To date, the aberrations in the DNA methylation patterns that are associated with different prognoses of G-CIMP− primary GBMs remain to be elucidated. Here, DNA methylation profiling of primary GBM tissues from 13 long-term survivors (LTS; overall survival ?18 months) and 20 short-term survivors (STS; overall survival ?9 months) was performed. Then G-CIMP+ samples were excluded. The differentially expressed CpG loci were identified between residual 18 STS and 9 LTS G-CIMP− samples. Methylation levels of 11 CpG loci (10 genes) were statistically significantly lower, and 43 CpG loci (40 genes) were statistically significantly higher in the tumor tissues of LTS than those of STS G-CIMP− samples (P < 0.01). Of the 43 CpG loci that were hypermethylated in LTS G-CIMP− samples, 3 CpG loci localized in the promoter of ALDH1A3. Furthermore, using an independent validation cohort containing 37 primary GBM samples without IDH1 mutation and MGMT promoter methylation, the hypermethylation status of ALDH1A3 promoter predicted a better prognosis with an accompanied low expression of ALDH1A3 protein. Taken together, our results defined prognosis-related methylation signatures systematically for the first time in G-CIMP− primary GBMs. ALDH1A3 promoter methylation conferred a favorable prognosis in G-CIMP− primary GBMs.  相似文献   
37.
Epithelioid glioblastoma (e-gbm) is a recently described variant of glioblastoma (GBM) which is associated with short survival and now added as a provisional entity to WHO 2016 classification of CNStumors. About half of these tumors show characteristic BRAF-V600E mutation. However, unlike conventional GBMs, e-gbm lack specific diagnostic and prognostic markers. Hence, we aimed to molecularly characterize these tumors. An extensive review of literature was performed.In a multi-institutional effort, all the cases of glioblastoma of year 2017 were reviewed. Cases with predominant epithelioid morphology were analysed. Seven cases of e-gbm (adults:4 and pediatric: 3) were identified. Duration of symptoms varied from 2 weeks to one month. Radiologically, all cases were supratentorial, contrast enhancing with solid and cystic appearance. Majority of the cases were immunopositive for GFAP (71%), EMA (71%), S100 (71%) and vimentin (85%). All the cases showed ATRX, INI-1 and H3K27me3 expression. BRAFV600Emutation was seen in 28% of cases. TERT mutation was seen in 40% cases, while one case showed EGFR amplification. H3F3A mutations and PTEN deletions were seen in none. Although e-gbms are rare, epithelioid morphology of a CNS tumor in a young adult or children with areas of necrosis needs thorough histomorphological and genetic workup.  相似文献   
38.
BackgroundGlioblastoma multiforme (GBM) is a tumor characterized by rapid cell proliferation and migration. GBM constitutes the most aggressive and deadly type of brain tumor and is classified into several subtypes that show high resistance to conventional therapies. There are currently no curative treatments for malignant glioma despite the numerous advances in surgical techniques, radiotherapy, and chemotherapy. Therefore, alternative approaches are required to improve GBM treatment.MethodsOur study proposes the use of photodynamic therapy (PDT) for GBM treatment, which uses chloro-aluminum phthalocyanine (AlClPc) encapsulated in a new drug delivery system (DDS) and designed as a nanoemulsion (AlClPc/NE). The optimal dark non-cytotoxic AlClPc/NE concentration for the U87 MG glioma cell model and the most suitable laser light intensity for irradiation were determined. Experimental U87 MG cancer cells were analyzed via MTT cell viability assay. Cellular localization of AlClPc, morphological changes, and cell death via the necrotic and apoptotic pathways were also evaluated.ResultsAlClPc remained in the cytoplasmic region at 24 h after administration. Additionally, treatment with 1.0 μmol/L AlClPc under light irradiation at doses lower than 140 mJ/cm resulted in morphological changes with 50 ± 6% cell death (p < 0.05). Moreover, 20 ± 2% of U87 MG cells underwent cell death via the necrotic pathway. Measurement of Caspase-9 and -3 activities also suggested that cells underwent apoptosis. Taken together, these results indicate that AlClPc/NE-PDT can be used in the treatment of glioblastoma by inducing necrotic and apoptotic cell death.ConclusionsOur findings suggest that AlClPc/NE-PDT induces cell death in U87 MG cells in a dose-dependent manner and could thus serve as an effective adjuvant treatment for malignant glioma. AlClPc/NE-PDT utilizes a low dose of visible light and can be used in combination with other classic GBM treatment approaches, such as a combination of chemotherapy and surgery.  相似文献   
39.
The polymerase chain reaction (PCR) assay for varicella zoster virus (VZV), herpes simplex virus (HSV)‐1 and HSV‐2 is available for use. Sometimes the differential diagnosis of the generalized herpes zoster (HZ), HSV1/2, and drug eruption is difficult. We report a case of HZ followed by the vesicular erythema multiforme (EM)‐like lesion. In this case the use of PCR was of great assistance. A 78‐year‐old Japanese man without any significant previous history of disease was admitted to our hospital complaining of zosteriform vesicle on an erythematous base from his right shoulder to the upper arm. We diagnosed him with HZ at the level of right Th2. In spite of the prompt start of antiviral therapy, a secondary new vesiculous erythema developed on his trunk. Clinically, it was quite difficult to differentiate the lesion from the generalized HZ. Rapid PCR assay of effusion and crust for VZV was performed. A PCR assay of VZV was positive for the crust taken from the primary lesion, while it was negative for the effusion and crust of the secondary widespread lesion. We diagnosed the secondary widespread lesion as an EM‐type drug eruption induced by acyclovir, or an EM associated with herpes zoster. We then stopped the use of acyclovir and applied steroid ointment of a very strong class for the secondary lesions, which improved after a few days. A PCR assay for VZV was useful for ruling out the generalized HZ in our case with secondary developed vesiculous lesions.  相似文献   
40.
IRE1α is an endoplasmic reticulum (ER)-resident transmembrane signaling protein and a cellular stress sensor. The protein harbors a cytosolic dual kinase/endoribonuclease activity required for adaptive responses to micro-environmental changes. In an orthotopic xenograft model of human glioma, invalidation of IRE1α RNase or/and kinase activities generated tumors with remarkably distinct phenotypes. Contrasting with the extensive angiogenesis observed in tumors derived from control cells, the double kinase/RNase invalidation reprogrammed mesenchymal differentiation of cancer cells and produced avascular and infiltrative glioblastomas with blood vessel co-option. In comparison, selective invalidation of IRE1α RNase did not compromise tumor angiogenesis but still elicited invasive features and vessel co-option. In vitro, IRE1α RNase deficient cells were also endowed with a higher ability to migrate. Constitutive activation of both enzymes led to wild-type-like lesions. The presence of IRE1α, but not its RNase activity, is therefore required for glioblastoma neovascularization, whereas invasion results only from RNase inhibition. In this model, two key mechanisms of tumor progression and cancer cell survival are functionally linked to IRE1α.  相似文献   
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