The potential role of lonidamine (LND) in the treatment of malignant glioma

Summary Up-to-date unsatisfactory results obtained in multimodality treatments of malignant glioma have prompted the research of new therapeutic modalities with unconventional modes of action. Lonidamine (LND) is a drug which reduces aerobic glycolytic activity in both human and experimental tumors. This effect mainly depends on the inhibition of mitochondrially-bound hexokinase (HK) which is present in large amounts in malignant cells. A Phase II study was conducted on patients with recurrent glioma; 12 patients were admitted to the study. Clinical side effects were moderate, necessitating a reduction of the dosage in only 1 case. The objective results were evaluated according to the indications of Levin. 2 responders and 3 cases of stable disease were observed out of 10 evaluable patients. The potential value of this new drug is discussed.     

脑胶质瘤中血脑屏障的超微结构特点

８例胶质瘤病例，标本分别取自同一病例的瘤体，瘤周水肿区和邻近脑组织。瘤体和瘤周水肿区血脑屏障超微结构变化无明显差异，内皮肿胀，毛细血管腔狭小，腔面有稀疏的绒毛样突起，内皮为无孔型，胞质内胞饮泡较多，内皮紧密连接增长，细胞连接间隙增宽，基膜完整，基膜完整，胶质膜缺损。     

原发性脑瘤的分子遗传学研究进展

［摘要］ 原发性脑瘤是发生于神经系统常见的疾病，高度恶性的胶质瘤占原发性脑瘤的40%，主要分为I型胶质母细胞瘤（继发性胶质母细胞瘤）和II型胶质母细胞瘤（原发性胶质母细胞瘤），二者的产生有着不同的遗传学改变。I型胶质母细胞瘤的产生途径是从一种恶性程度较低的星形细胞瘤（II级，主要为p53基因突变和血小板来源的生长因子/受体过表达）至恶性的间变型星型细胞瘤（III级，主要为Rb基因突变，CDK4基因扩增，9p、11p、13q和19q的等位基因缺失），再到胶质母细胞瘤（IV级，最常见的遗传学改变是7号和20号染色体的获得,10号染色体的丢失以及PTEN和LRRC4基因的缺失，PDGFα及其受体的过表达）的渐进的发展过程；而II型胶质母细胞瘤则是一种没有恶性程度渐进过程的原发性胶质母细胞瘤，表皮生长因子受体基因的扩增是最常见的遗传学改变。     

Role of fibronectin-stimulated tumor cell migration in glioma invasion in vivo: clinical significance of fibronectin and fibronectin receptor expressed in human glioma tissues

In order to clarify the role of fibronectin in glioma invasion in vivo, we analyzed the relationship between fibronectin-stimulated cell migration and adhesion in 14 primary glioma cells and the expression of fibronectin and the fibronectin receptor in the corresponding tumor tissues. The tumors comprised nine glioblastomas (GB) and five anaplastic gliomas (AG) consisting of two astrocytomas, two oligoastrocytomas and one ependymoma. All glioma cells tested in the primary cell culture were found to migrate to fibronectin in a dose-dependent manner. The extent of cell migration to fibronectin was not significantly different for the GB and AG groups. On the other hand, cell adhesion to fibronectin in the AG was much stronger than that in the GB group. Immunohistochemistry demonstrated that fibronectin positively stained in the extra-cellular matrix (ECM) in eight cases and that the fibronectin receptor was positive in tumor cell membranes in 10 cases. In addition, cellular fibronectin isoforms containing ED-A and ED-B sequences were found to be immunolocalized in the tumor cells and the ECM of GB. These isoforms were also specifically expressed in tumor vessels within tumor tissues, but not in those within normal brain tissues. Cell migration tended to be expressed more strongly by glioma cells derived from tumor tissues in which fibronectin was posi-tively immunolocalized in the ECM than from tissues with negative fibronectin in the ECM. Four glioma cells derived from GB whose tumor cells did not positively stain for fibronectin receptors migrated much less extensively to fibronectin than other glioma cells whose tissues showed positive staining for the fibronectin receptor. Of these four GB, two had loss of heterozygosity in the locus of fibronectin receptor b1 gene. These results suggest that fibronectin deposited in the extracellular matrix of tumors, which can be derived from both plasma and the tumor cell itself, strongly promotes the migration of glioma cells, and that expression of the fibronectin receptor may play a critical role in the biological behavior of the tumor cells, particularly in fibronectin-stimulated cell migration in vivo.© Kluwer Academic Publishers 1998     

Shared amino acid sequences in the NDβN and Nα regions of the T cell receptors of tumor-infiltrating lymphocytes within malignant glioma

The purpose of this study was to assess the V-(D)-J junctional region of the T cell receptor (TCR), the CDR3 region, which is responsible for glioma-specific antigen contact in αβ TCR-mediated recognition. We sequenced the TCR α and β chians of Vα7, and Vβ13.1 cDNA derived from tumor-infiltrating lymphocytes (TIL) of 12 glioma patients and also the corresponding clones from the patients' peripheral blood lymphocytes (PBL). A shared Vβ13.1 DJ sequence of the CDR3 region, NDβN, was demonstrated in 49 of 66 Vβ13.1⁺ clones (74.2 %) from the glioma TIL, whereas only 4 of 33 clones (12.1 %) were observed in the Vβ13.1⁺ clones from the PBL (p < 0.001). A common VDJ sequence, FCASS (Vβ13.1)-YRLPWGTSDS (NDβN)-GELFF(Jβ2.2), was observed not only in the gliomas from each patient, but also among all the patients with a preference for Vβ13.1. In contrast, the amino acid sequences of the Vβ13.1⁺ PBL clones were diverse and random. Next, we sequenced subclones from other Vβ subfamilies randomly selected to compare their VDJ region rearrangements (Vβ3 and Vβ5.1). In contrast to Vβ13.1, the amino acid sequences of these junctional regions were completely different in these subclones. The V-J junctional region of the α chain is dominated by a few clones in some patients, and no shared amino acid sequences were detected in the TCR Vα junctional region. However, in the Nα region of the Vα7-bearing TIL clones, arginine was used in 27 of 44 clones (61.4%) compared to only 3 of 12 clones from the PBL (p < 0.05). These results are consistent with the hypothesis that a clonal expansion/accumulation of glioma lineage-specific T cells occurred in vivo at the tumor site and that these T cells may be recognizing glioma-specific antigens.     

Correlation between the occurrence of 1H-MRS lipid signal, necrosis and lipid droplets during C6 rat glioma development

The aim of this study was to investigate the possible correlation between the 1H MRS mobile lipid signal, necrosis and lipid droplets in C6 rat glioma. First, the occurrence of necrosis and lipid droplets was determined during tumor development, by a histological analysis performed on 34 rats. Neither necrosis nor lipid droplets were observed before 18 days post-implantation. At later stages of development, both necrosis and lipid droplets were apparent, the lipid droplets being mainly located within the necrotic areas. Using a second group of eight rats, a temporal correlation was evidenced between mobile lipid signal detected by in vivo single-voxel one- (136 ms echo time) and two-dimensional J-resolved 1H MR spectroscopy, and the presence of necrosis and lipid droplets on the histological sections obtained from the brains of the same rats. Finally, spatial distribution of the mobile lipid signal was analyzed by chemical-shift imaging performed on a third group of eight animals, at the end of the tumor growth. The spectroscopic image corresponding to the resonance of mobile lipids had its maximum intensity in the center of the tumor where necrotic regions were observed on the histological sections. These necrotic areas contained large amounts of lipid droplets. All these results suggest that mobile lipids detected in vivo by 1H MRS (136 ms echo time) in C6 rat brain glioma arise mainly from lipid droplets located in necrosis.     

Therapeutic potential of chlorotoxin-like neurotoxin from the Chinese scorpion for human gliomas

Chlorotoxin, one of the key toxins in scorpion Leiurus quinquestriatus venom, has been shown to bind specifically to glioma cell surface as a specific chloride channel blocker. In this study, a purified, recombinant chlorotoxin-like peptide from the scorpion Buthus martensii Karsch (named rBmK CTa) was characterized by in vivo and in vitro studies. The results from cell proliferation assay with human glioma (SHG-44) cells showed that rBmK CTa inhibits the growth of glioma cells in a dose-dependent manner, with an IC₅₀ value of approximately 0.28 μM. Under the same conditions, the IC₅₀ value for normal astrocytes increased to 8 μM. This clearly indicated that rBmK CTa had specific toxicity against glioma cells but not astrocytes. Results from whole-cell patch-clamp recording showed that chloride current in SHG-44 was inhibited by rBmK CTa in a voltage-dependent manner and percent inhibitions for the blocking action of rBmK CTa (0.07 and 0.14 μM) on I_Cl was 17.64 ± 3.06% and 55.86 ± 2.83%, respectively. Histological analysis of rBmK CTa treated mice showed that brain, leg muscle and cardiac muscle were the target organs of this toxin. These results suggest that rBmK CTa may have potential therapeutic application in clinical treatment of human glioma. It represents an approach for developing a novel therapeutic agent.     

人脑胶质瘤侵袭微生态系统的形态学观察

目的　探讨人脑胶质瘤侵袭微生态系统的形态学特征。　方法　利用光镜及透射电镜观察 12例手术切除的脑胶质瘤标本中微血管内皮细胞和基底膜及其与肿瘤细胞的相互关系。　结果　光镜下可见侵袭性生长的瘤细胞可在血管周形成巢状结构。电镜下不同胶质细胞起源的胶质瘤中的微血管内皮细胞基本上为无孔型 ,偶见窗孔形成。内皮细胞下基质完整 ,基底膜呈局限性或广泛性增厚 ,有的伴有多层基板样结构形成。基底膜靠近瘤细胞侧常出现大小不等、数量不一的虫蚀样空洞 ,含有较大空洞的基底膜常突向瘤细胞侧。有的血管外腔扩张 ,腔内可见瘤细胞以单个形式侵袭 ,少见瘤细胞伸出伪足突入基底膜及穿透内皮细胞间隙现象 ,瘤细胞与基底膜相互接触处呈光滑平整的界面。　结论　无孔型内皮细胞、肿瘤微血管基底膜结构的局限性或广泛性增厚和虫蚀样空洞的改变 ,及少见瘤细胞伸出伪足突入其间 ,可能是不同胶质细胞起源的人脑胶质瘤侵袭微生态系统形态学上共有的特征     

Fuzzy rules to predict degree of malignancy in brain glioma

The current pre-operative assessment of the degree of malignancy in brain glioma is based on magnetic resonance imaging (MRI) findings and clinical data. 280 cases were studied, of which 111 were high-grade malignancies and 169 were low-grade, so that regular and interpretable patterns of the relationships between glioma MRI features and the degree of malignancy could be acquired. However, as uncertainties in the data and missing values existed, a fuzzy rule extraction algorithm based on a fuzzy min-max neural network (FMMNN) was used. The performance of a multi-layer perceptron network (MLP) trained with the error back-propagation algorithm (BP), the decision tree algorithm ID3, nearest neighbour and the original fuzzy min-max neural network were also evaluated. The results showed that two fuzzy decision rules on only six features achieved an accuracy of 84.6% (89.9% for low-grade and 76.6% for high-grade cases). Investigations with the proposed algorithm revealed that age, mass effect, oedema, post-contrast enhancement, blood supply, calcification, haemorrhage and the signal intensity of the T1-weighted image were important diagnostic factors.