Updates on management of gliomas in the molecular age

Gliomas are primary brain tumors derived from glial cells of the central nervous system,afflicting both adults and children with distinct characteristics and therapeutic challenges.Recent developments have ushered in novel clinical and molecular prognostic factors,reshaping treatment paradigms based on classi-fication and grading,determined by histological attributes and cellular lineage.This review article delves into the diverse treatment modalities tailored to the specific grades and molecular classifications of gliomas that are currently being discussed and used clinically in the year 2023.For adults,the therapeutic triad typically consists of surgical resection,chemotherapy,and radiotherapy.In contrast,pediatric gliomas,due to their diversity,require a more tailored approach.Although complete tumor excision can be curative based on the location and grade of the glioma,certain non-resectable cases demand a chemotherapy approach usually involving,vincristine and carboplatin.Addi-tionally,if surgery or chemotherapy strategies are unsuccessful,Vinblastine can be used.Despite recent advancements in treatment methodologies,there remains a need of exploration in the literature,particularly concerning the efficacy of treatment regimens for isocitrate dehydrogenase type mutant astrocytomas and fine-tuned therapeutic approaches tailored for pediatric cohorts.This review article explores into the therapeutic modalities employed for both adult and pediatric gliomas in the context of their molecular classification.

Current challenges in the treatment of gliomas:The molecular era

Gliomas originate from glial cells in the central nervous system.Approximately 80%-85%of malignant brain tumors in adults are gliomas.The most common central nervous system tumor in children is low-grade pediatric glioma.Diagnosis was determined by histological features until 2016 when the World Health Organization classification integrated molecular data with anatomopathological information to achieve a more integral diagnosis.Molecular characterization has led to better diagnostic and prognostic staging,which in turn has increased the precision of treatment.Current efforts are focused on more effective therapies to prolong survival and improve the quality of life of adult and pediatric patients with glioma.However,improvements in survival have been modest.Currently,clinical guidelines,as well as the article by Mohamed et al accompanying this editorial piece,are adapting treatment recommendations(surgery,chemotherapy,and radiotherapy)according to diagnosis and prognosis guided by molecular biomarkers.Furthermore,this paves the way for the design of clinical trials with new therapies,which is especially important in pediatric gliomas.

New targets for cancer promotion and therapy in gliomas: Scinderin

Glioma is one of the most common primary intracranial tumors,characterized by invasive growth and poor prognosis.Actin cytoskeletal rearrangement is an essential event in tumor cell migration.Scinderin(SCIN),an actin severing and capping protein that regulates the actin cytoskeleton,is involved in the prolif-eration and migration of certain cancer cells.However,its biological role and molecular mechanism in glioma remain unclear.Lin et al explored the role and mechanism of SCIN in gliomas.The results showed that SCIN mechanically affected cytoskeleton remodeling and inhibited the formation of lamellipodia via RhoA/FAK signaling pathway.This study identifies the cancer-promoting role of SCIN and provides a potential therapeutic target for SCIN in glioma treatment.

The Role of Predominant Expression of Th2 Type Cytokines Gene in the Genesis and Development of Human Gliomas

Objective: To explore the expression of Th1/Th2 cytokines gene in human gliomas and its role in the genesis and development of human gliomas.Methods: Using IL-2 and IFNγ as Th1 type cytokines, IL-4, IL-6 and IL-10 as Th2 type cytokines, the biological activity of cytokines in the supernatant of glioma cell lines was assayed by ELISA method, and the gene expression of Th1/Th2 cytokines in human glioma cells, glioma infiltrating lymphocytes and glioma cell lines were detected by RT-PCR.Results: There was predominant expression of Th2 type cytokines in human glioma cells, glioma infiltrating lymphocytes and glioma cell lines, but there was no such expression in normal brain tissues.Conclusion: It suggested that there is a relationship between the Th2 type cytokines expression in human gliomas and the immunosupressive status of human glioma patients. The predominant expression of Th2 type cytokines may play an important role in the genesis and development of human gliomas. Key words glioma - Th1/Th2 - gene expression - RT-PCR This project was supported by a grant from National Natural Sciences foundation of China (No. 30271335).

肿瘤组织微小RNA-542-3p、血管细胞黏附分子-1表达特征与脑胶质瘤术后复发的关系及预测价值

目的:探讨肿瘤组织中微小RNA-542-3p(miR-542-3p)、血管细胞黏附分子-1(VCAM-1)表达与脑胶质瘤手术后复发的关系及其预测价值。方法:选取实施手术治疗的脑胶质瘤患者91例进行临床研究,其中43例患者于术后1年出现术后复发(复发组)、48例患者手术后1年检查未出现复发病灶(非复发组),对比两组第一次手术后病灶组织标本中的miR-542-3p、VCAM-1蛋白表达差异,并分析miR-542-3p、VCAM-1蛋白表达与胶质瘤术后复发的关系及其预测复发的价值。结果:复发组患者脑胶质瘤组织中miR-542-3p表达水平低于非复发组,复发组患者脑胶质瘤组织中VCAM-1蛋白阳性表达率高于非复发组,差异具有统计学意义(均P<0.05);复发组患者脑胶质瘤组织病理学分级≥Ⅲ级患者占比、低分化患者占比、非全切手术方式患者占比、肿瘤浸润率均高于非复发组,复发组患者术后放化疗患者占比低于非复发组,差异具有统计学意义(均P<0.05)。miR-542-3p表达降低、VCAM-1蛋白阳性表达、手术范围非全切是脑胶质瘤手术后复发的独立危险因素(均P<0.05);miR-542-3p表达、VCAM-1蛋白预测脑胶质瘤手术后复发的曲线下面积AUC值分别为0.784(95%CI:0.690~0.877)、0.725(95%CI:0.621~0.829)。结论:脑胶质瘤组织中miR-542-3p表达、VCAM-1蛋白表达与肿瘤手术后复发有密切关系,用于临床预测有一定的参考价值。

灵芝提取物通过PBX3/MAPK通路对胶质瘤细胞恶性生物学行为的作用机制研究

目的探究灵芝提取物(GLE)是否可通过前B细胞白血病同源盒基因3(PBX3)/丝裂原活化蛋白激酶(MAPK)通路影响U251人胶质瘤细胞恶性生物学行为。方法2022年1月至2023年1月进行该研究。含不同浓度GLE培养液(0、50、100、200 mg/L GLE)培养U251细胞48 h,采用细胞计数试剂盒(CCK-8)法、流式细胞术、平板克隆实验、细胞划痕试验及迁移和侵袭(Transwell)实验来评估细胞的存活率、凋亡情况、集落形成能力、迁移与侵袭特性;实时定量聚合酶链反应(RT-qPCR)检测PBX3、细胞外信号调节酶(ERK)mRNA表达水平;蛋白质印迹法检测PBX3、原癌基因c-RAF(Raf-1)、磷酸化Raf-1(p-Raf-1)、信号通路细胞外信号调节酶1/2(ERK1/2)、磷酸化ERK1/2(p-ERK1/2)蛋白表达情况。结果0、50、100、200 mg/L GLE下U251细胞存活率分别为100%、(86.62±4.26)%、(67.68±3.49)%、(50.84±3.39)%、(40.13±3.25)%,差异有统计学意义(P<0.05);0、50、100、200 mg/L GLE下U251细胞凋亡率、集落形成数、划痕愈合率、侵袭细胞数、PBX3、ERK mRNA及PBX3、p-Raf-1、p-ERK1/2蛋白相对表达水平比较,差异有统计学意义(P<0.05);随着GLE浓度的增加,U251细胞存活率、划痕愈合率、PBX3与ERK mRNA相对表达水平及RAS、PBX3、p-Raf-1、p-MEK1/2、p-ERK1/2蛋白相对表达水平均降低,集落形成数及侵袭细胞数均减少,细胞凋亡率升高;GLE作用效果呈剂量性依赖(P<0.05)。结论GLE可抑制胶质瘤细胞增殖、克隆形成、迁移及侵袭等恶性生物学特性,并诱导其凋亡,其作用机制可能与阻断PBX3/MAPK通路的激活相关。

Gαi蛋白在恶性肿瘤中的研究进展

恶性肿瘤的发生与细胞信号转导紊乱密切相关。G蛋白家族中的Gαi蛋白作为信号转导的重要参与者,在脑胶质瘤、骨肉瘤、乳腺癌和前列腺癌等恶性肿瘤中存在异常表达或活性改变。目前认为,Gαi蛋白在肿瘤的发生和发展过程中发挥作用,可能通过调控细胞增殖、迁移和凋亡等途径参与癌变机制,这为靶向Gαi蛋白的个性化治疗提供了理论依据。未来的研究可以进一步探讨Gαi蛋白的具体分子机制及其在临床治疗中的应用潜力,为新型靶向药物的开发提供指导。

细胞周期蛋白依赖性激酶7抑制剂THZ1对脑胶质瘤干细胞干性的调控及机制

背景:THZ1是一种细胞周期蛋白依赖性激酶7的抑制剂,可以抑制多种肿瘤细胞的增殖,但THZ1是否可以通过Wnt/β-catenin信号通路影响脑胶质瘤干细胞的干性尚不清楚。目的:探究THZ1对脑胶质瘤细胞U87干性的影响及机制。方法:培养脑胶质瘤细胞U87形成干细胞球并通过Western blot验证干性相关蛋白的表达;采用CCK-8法检测THZ1作用于U87细胞的半数抑制浓度(IC_(50));通过克隆实验、划痕实验、Transwell迁移实验确定THZ1对U87细胞增殖、迁移的影响;分析THZ1处理对U87干细胞成球率及干细胞球体大小的影响;Western blot检测干性相关蛋白CD133、ABCG2、Nanog、OCT4、SOX2和上皮-间充质转化相关蛋白E-cadherin、N-cadherin、Occludin、Snail以及Wnt/β-catenin通路相关蛋白Axin1、β-Catenin、Wnt-5a、GSK3β、Cyclind-1、C-myc的表达变化。结果与结论:①与贴壁细胞相比,U87干细胞干性相关蛋白Nestin、CD133、ABCG2、Nanog、OCT4、SOX2表达明显升高;②与对照组相比,THZ1减弱了U87细胞的增殖和迁移能力;③THZ1抑制U87干细胞成球率及球体大小,下调干性相关蛋白的表达;④THZ1处理后,U87干细胞中N-cadherin、Snail蛋白表达降低,而E-cadherin、Occludin蛋白表达升高;(5)THZ1处理使U87干细胞中Wnt/β-catenin通路相关蛋白Axin1、β-Catenin、Wnt-5a、GSK3β、Cyclind-1、C-myc表达降低。结果表明:THZ1通过下调Wnt/β-catenin信号通路相关分子表达,抑制脑胶质瘤细胞U87的增殖、迁移,抑制U87干细胞成球能力、干性相关蛋白表达和上皮-间充质转化能力。

P27/Kipl Expression in Gliomas and Its Clinical Significance

Objective： To study p27/Kipl expression in gliomas and its application value. Methods： Imo munohistochemical technique was used to detect the exprssion of p27/Kipl gene in 48 different malignant grade human brain glioma tissues categorized according to WHO classification and 12 normal human brain tissues,which were analyzed quantitatively by using the image system and compared retrospectively with the patients＇ clinical characteristics. Results： In this series, the immunohistochemical reaction for p27/Kipl was confined to the nuclei. The abnormal positive expression rate of p27/Kipl in gliomas was found to be higher than that in normal tissues （P〈0.05）. The positive nuclei expression of p27/Kipl decreased in number and staining intensity with the increasing degree of histological malignancy （P〈0.05）. Lower expression of p27/Kipl was associated with poor prognosis （P〈0.05）. P27/Kipl expression could be regarded as an independent prognostic factor. Conclusion： The abnormal expression of p27/Kipl may be closely related to the occurrence and development of gliomas, and also can be used to evaluate the prognosis independently.

Impacts of Nutlin-3a and exercise on murine double minute 2-enriched glioma treatment

Recent research has demonstrated the impact of physical activity on the prognosis of glioma patients,with evidence suggesting exercise may reduce mortality risks and aid neural regeneration.The role of the small ubiquitin-like modifier(SUMO)protein,especially post-exercise,in cancer progression,is gaining attention,as are the potential anti-cancer effects of SUMOylation.We used machine learning to create the exercise and SUMO-related gene signature(ESLRS).This signature shows how physical activity might help improve the outlook for low-grade glioma and other cancers.We demonstrated the prognostic and immunotherapeutic significance of ESLRS markers,specifically highlighting how murine double minute 2(MDM2),a component of the ESLRS,can be targeted by nutlin-3.This underscores the intricate relationship between natural compounds such as nutlin-3 and immune regulation.Using comprehensive CRISPR screening,we validated the effects of specific ESLRS genes on low-grade glioma progression.We also revealed insights into the effectiveness of Nutlin-3a as a potent MDM2 inhibitor through molecular docking and dynamic simulation.Nutlin-3a inhibited glioma cell proliferation and activated the p53 pathway.Its efficacy decreased with MDM2 overexpression,and this was reversed by Nutlin-3a or exercise.Experiments using a low-grade glioma mouse model highlighted the effect of physical activity on oxidative stress and molecular pathway regulation.Notably,both physical exercise and Nutlin-3a administration improved physical function in mice bearing tumors derived from MDM2-overexpressing cells.These results suggest the potential for Nutlin-3a,an MDM2 inhibitor,with physical exercise as a therapeutic approach for glioma management.Our research also supports the use of natural products for therapy and sheds light on the interaction of exercise,natural products,and immune regulation in cancer treatment.

Targeting capabilities of engineered extracellular vesicles for the treatment of neurological diseases

Recent advances in research on extracellular vesicles have significantly enhanced their potential as therapeutic agents for neurological diseases.Owing to their therapeutic properties and ability to cross the blood–brain barrier,extracellular vesicles are recognized as promising drug delivery vehicles for various neurological conditions,including ischemic stroke,traumatic brain injury,neurodegenerative diseases,glioma,and psychosis.However,the clinical application of natural extracellular vesicles is hindered by their limited targeting ability and short clearance from the body.To address these limitations,multiple engineering strategies have been developed to enhance the targeting capabilities of extracellular vesicles,thereby enabling the delivery of therapeutic contents to specific tissues or cells.Therefore,this review aims to highlight the latest advancements in natural and targeting-engineered extracellular vesicles,exploring their applications in treating traumatic brain injury,ischemic stroke,Parkinson's disease,Alzheimer's disease,amyotrophic lateral sclerosis,glioma,and psychosis.Additionally,we summarized recent clinical trials involving extracellular vesicles and discussed the challenges and future prospects of using targeting-engineered extracellular vesicles for drug delivery in treating neurological diseases.This review offers new insights for developing highly targeted therapies in this field.

Stem cells tropism for malignant gliomas

Various studies have demonstrated the tremendous tropism of stem cells for malignant gliomas,making these cells a potential vehicle for delivery of therapeutic genes to disseminated glioma cells.However,little is known about the mechanisms underlying the glioma-induced tropism of stem cells.Soluble factors including chemokines or growth factors released and expressed by glioma cells at least mediate the tropism of stem cells for gliomas.Here we review the possible mechanisms of stem cells tropism for malignant gliomas.

Prognostic implications of epidermal growth factor receptor variant Ⅲ expression and nuclear translocation in Chinese human gliomas

Objective: To determine the prognostic implications and clinical significance of epidermal growth factor receptor variant Ⅲ(EGFRvⅢ) expression and EGFRvⅢ nuclear translocation in Chinese human gliomas.Methods: We retrospectively examined EGFRvⅢ expression and EGFRvⅢ nuclear translocation using immunohistochemistry in specimens of 240 Chinese patients with glioma, including 84 World Health Organization(WHO) II gliomas, 84 WHO Ⅲ gliomas and 72 glioblastomas(WHO IV). Factors that correlated with EGFRvⅢ and EGFRvⅢ nuclear translocation expression were analyzed by the Chi-square test. Kaplan-Meier methodology and Cox regression were used for the survival analysis.Results: Log-rank tests showed that patient age, Karnofsky performance scale(KPS) score, tumor grade,EGFRvⅢ expression, EGFRvⅢ nuclear translocation, 1 p/19 q codeletion, isocitrate dehydrogenase(IDH)mutation, Ki-67 labeling index and O6-methylguanine-DNA methyltransferase(MGMT) status(P<0.05) were significantly correlated with overall survival(OS) time. Multivariate Cox regression analysis revealed that patient age, tumor grade, EGFRvⅢ nuclear translocation, 1 p/19 q codeletion, and IDH mutation(P<0.05) were significantly correlated with OS. Patients with a high level of EGFRvⅢ nuclear translocation(≥7%) had both significantly shorter OS [hazard ratio(HR): 1.920, 95% confidence interval(95% CI): 1.228-3.003, P=0.004] and progression-free survival(PFS) times(HR: 1.661, 95% CI: 1.116-2.471, P=0.012) than those with a low level of EGFRvⅢ nuclear translocation(<7%).Conclusions: A high level of EGFRvⅢ nuclear translocation in glioma is an independent factor indicating a poor prognosis, but EGFRvⅢ expression is not an independent clinical prognostic factor. The level of EGFRvⅢ nuclear translocation maybe a novel and crucial prognostic biomarker in glioma.

Radiotherapy of high-grade gliomas: current standards and new concepts, innovations in imaging and radiotherapy, and new therapeutic approaches

The current standards in radiotherapy of high-grade gliomas(HGG) are based on anatomic imaging techniques, usually computed tomography(CT) scanning and magnetic resonance imaging(MRI). The guidelines vary depending on whether the HGG is a histological grade 3 anaplastic glioma(AG) or a grade 4 glioblastoma multiforme(GBM). For AG, T2-weighted MRI sequences plus the region of contrast enhancement in T1 are considered for the delineation of the gross tumor volume(GTV), and an isotropic expansion of 15 to 20 mm is recommended for the clinical target volume(CTV). For GBM, the Radiation Therapy Oncology Group favors a two-step technique, with an initial phase(CTV1) including any T2 hyperintensity area(edema) plus a 20 mm margin treated with up to 46 Gy in 23 fractions, followed by a reduction in CTV2 to the contrast enhancement region in T1 with an additional 25 mm margin. The European Organisation of Research and Treatment of Cancer recommends a single-phase technique with a unique GTV, which comprises the T1 contrast enhancement region plus a margin of 20 to 30 mm. A total dose of 60 Gy in 30 fractions is usually delivered for GBM, and a dose of 59.4 Gy in 33 fractions is typically given for AG. As more than 85% of HGGs recur in field, dose-escalation studies have shown that 70 to 75 Gy can be delivered in 6 weeks with relevant toxicities developing in < 10% of the patients. However, the only randomized dose-escalation trial, in which the boost dose was guided by conventional MRI, did not show any survival advantage of this treatment over the reference arm. HGGs are amongst the most infiltrative and heterogeneous tumors, and it was hypothesized that the most highly aggressive areas were missed; thus, better visualization of these high-risk regions for radiation boost could decrease the recurrence rate. Innovations in imaging and linear accelerators(LINAC) could help deliver the right doses of radiation to the right subvolumes according to the dose-painting concept. Advanced imaging techniques provide functional information on cellular density(diffusion MRI), angiogenesis(perfusion MRI), metabolic activity and cellular proliferation [positron emission tomography(PET) and magnetic resonance spectroscopy(MRS)]. All of these non-invasive techniques demonstrated good association between the images and histology, with up to 40% of HGGs functionally presenting a high activity within the non- contrast-enhanced areas in T1. New LINAC technologies, such as intensity-modulated and stereotactic radiotherapy, help to deliver a simultaneous integrated boost(SIB) > 60 Gy. Trials delivering a SIB into a biological GTV showed the feasibility of this treatment, but the final results, in terms of clinical benefits for HGG patients, are still pending. Many issues have been identified: the variety of MRI and PET machines(and amino-acid tracers), the heterogeneity of the protocols used for image acquisition and post-treatment, the geometric distortion and the unreliable algorithms for co-registration of brain anatomy with functional maps, and the semi-quiescent but highly invasive HGG cells. These issues could be solved by the homogenization of the protocols and software applications, the simultaneous acquisition of anatomic and functional images(PET-MRI machines), the combination of complementary imaging tools(perfusion and diffusion MRI), and the concomitant addition of some ad hoc targeted drugs against angiogenesis and invasiveness to chemoradiotherapy. The integration of these hybrid data will construct new synthetic metrics for fully individualized treatments.

Genomic profiling of lower-grade gliomas uncovers cohesive disease groups:implications for diagnosis and treatment

Lower-grade gliomas(including low-and intermediate-grade gliomas,World Health Organization grades II and III)are diffusely infiltrative neoplasms that arise most often in the cerebral hemispheres of adults and have traditionally been classified based on their presumed histogenesis as astrocytomas,oligodendrogliomas,or oligoastrocytomas.Although the histopathologic classification of lower-grade glioma has been the accepted standard for nearly a century,it suffers from high intra-and inter-observer variability and does not adequately predict clinical outcomes.Based on integrated analysis of multiplatform genomic data from The Cancer Genome Atlas,lower-grade gliomas have been found to segregate into three cohesive,clinically relevant molecular classes.Molecular classes were closely aligned with the status of isocitrate dehydrogenase(IDH)mutations,tumor protein 53 mutations and the co-deletion of chromosome arms 1 p and 19q,but were not closely aligned with histologic classes.These findings emphasize the potential for improved definition of clinically relevant disease subsets using integrated molecular approaches and highlight the importance of biomarkers for brain tumor classification.

Clinical management and survival outcomes of patients withdifferent molecular subtypes of diffuse gliomas in China(2011–2017):a multicenter retrospective study from CGGA

Objective:We aimed to summarize the clinicopathological characteristics and prognostic features of various molecular subtypes of diffuse gliomas(DGs)in the Chinese population.Methods:In total,1,418 patients diagnosed with DG between 2011 and 2017 were classified into 5 molecular subtypes according to the 2016 WHO classification of central nervous system tumors.The IDH mutation status was determined by immunohistochemistry and/or DNA sequencing,and 1p/19q codeletion was detected with fluorescence in situ hybridization.The median clinical follow-up time was 1,076 days.T-tests and chi-square tests were used to compare clinicopathological characteristics.Kaplan‒Meier and Cox regression methods were used to evaluate prognostic factors.Results:Our cohort included 15.5%lower-grade gliomas,IDH-mutant and 1p/19q-codeleted(LGG-IDHm-1p/19q);18.1%lowergrade gliomas,IDH-mutant(LGG-IDHm);13.1%lower-grade gliomas,IDH-wildtype(LGG-IDHwt);36.1%glioblastoma,IDHwildtype(GBM-IDHwt);and 17.2%glioblastoma,IDH-mutant(GBM-IDHm).Approximately 63.3%of the enrolled primary gliomas,and the median overall survival times for LGG-IDHm,LGG-IDHwt,GBM-IDHwt,and GBM-IDHm subtypes were 75.97,34.47,11.57,and 15.17 months,respectively.The 5-year survival rate of LGG-IDHm-1p/19q was 76.54%.We observed a significant association between high resection rate and favorable survival outcomes across all subtypes of primary tumors.We also observed a significant role of chemotherapy in prolonging overall survival for GBM-IDHwt and GBM-IDHm,and in prolonging post-relapse survival for the 2 recurrent GBM subtypes.Conclusions:By controlling for molecular subtypes,we found that resection rate and chemotherapy were 2 prognostic factors associated with survival outcomes in a Chinese cohort with DG.

EXPRESSION AND SWITCHING OF TH1/TH2 TYPE CYTOKINESGENE IN HUMAN GLIOMAS

Objective To study the expression and switching of Thl/Th2 cytokines gene in human gliomas and its effects on occurring and developing of human gliomas. Methods Interleukin（IL）-2 and interferon-3, represent Thl type cytokines. IL-4, IL-6, IL-10, and IL-13 represent Th2 type cytokines. The gene expressions of Th1/Th2 cytokines in human glioma cells, glioma infiltrating lymphocytes, and glioma cell lines were detected by reverse transcription polymerase chain reaction （RT-PCR）. The biological activity of cytokines in the supematant of glioma cell lines was assayed by enzyme-linked immunosorbent assay （ELISA） method. Results The total positive rates of Th1 and Th2 type cytokines gene in human glioma cells were 14.77% and 75%. The total positive rates of Th1 and Th2 type cytokines gene in glioma infiltrating lymphocytes were 22.73% and 68.17%. There was obviously predominant expression of Th2 type cytokines in human glioma tissues, glioma infiltrating lymphocytes, and glioma cell lines. There was no unbalanced expression of Th1/Th2 cytokines in normal brain tissues. Conclusion There is a predominant expression of Th2 type cytokines in human glioma cells. The switching of Th1/Th2 cytokines gene may play an important role in the occurring and developing of human gliomas.

A Phase II Study of Antineoplastons A10 and AS2-1 in Patients with Brainstem Gliomas. The Report on Non-Diffuse Intrinsic Pontine Glioma (Protocol BT-11)

Inoperable brainstem gliomas (BSG) are among the most difficult to treat malignancies. In the intent-to-treat (ITT) population of the BT-11 study for BSG, forty patients (median age 11.2 years old) were enrolled. Antineoplastons A10 and AS2-1 (ANP) were administered intravenously daily. The median daily dose of A10 was 8.70 g/kg/day and AS2-1 was 0.32 g/kg/day. Efficacy analyses were conducted in two subgroups: recurrent pediatric diffuse intrinsic pontine glioma (RPDIPG, N?= 17) and non-diffuse intrinsic pontine glioma (NDIPG, N?= 11). This paper reports the results of the study of the efficacy and safety of ANP in patients with NDIPG. The results in the RPDIPG group were reported before;complete response (CR) was 6%, partial response (PR) 23.5%, and stable disease (SD) 17.6%. One year overall survival (OS) was 29.4%, 2 years 11.8%, and 5, 10, and 15 years 6%. In the NDIPG group, there were 36% CR and 27.5% SD. OS at 1, 5, 10, and 15 years was 82%, 73%, 62%, and 50% correspondingly. There was only one serious adverse event (9%) reported in NDIPG represented by hypokalemia, Grade 4. The results suggest that ANP shows efficacy and an acceptable tolerability profile in patients with RPDIPG and NDIPG.

High-grade gliomas: reality and hopes

In this issue of the Chinese Journal of Cancer, European experts review current standards, trends, and future prospects in the difficult domain of high-grade glioma. In all fields covered by the different authors, the progress has been impressive. For example, discoveries at the molecular level have already impacted imaging, surgery, radiotherapy, and systemic therapies, and they are expected to play an increasing role in the management of these cancers. The European Organization for Research and Treatment of Cancer(EORTC) has pioneered new treatment strategies and contributed to new standards. The articles in this issue will cover basic molecular biological principles applicable today, novel surgical approaches, innovations in radiotherapy planning and delivery, evidence-based standards for radiotherapy alone or combined with chemotherapy, current standards and novel approaches for systemic treatments, and the important but often neglected field of health-related quality of life. Despite the advances described in these articles, the overall prognosis of high-grade glioma, especially glioblastoma, remains poor, and more research is needed to address this problem.

Promoter hypomethylation regulates CD133 expression in human gliomas

Brain tumor-initiating cells （BTICs） have been enriched using antibodies against the cell surface protein CD133; however, the biological relevance and the regulatory mechanism of CD133 expression in human gliomas are not yet understood. In this study, we initially demonstrated that CD133 was overexpressed in high-grade human glioblastomas where CD133-positive cells were focally observed as a micro-cluster. In addition, CD133 transcripts with exon 1A, 1B, or 1C were predominantly expressed in glioblastomas. To elucidate the mechanism regulating this aberrant expression of CD133, three proximal promoters （P1, P2, and P3） containing a CpG island were isolated. In U251MG and T98G glioblastoma cells, the P1 region flanking exon 1A exhibited the highest activity among the three promoters, and this activity was significantly inactivated by in vitro methylation. After treatment with the demethylating agent 5-azacytidine and/or the histone deacetylase inhibitor valproic acid, the expression level of CD133 mRNA was significantly restored in glioma cells. Importantly, hypomethylation of CpG sites within the P1, P2, and P3 regions was observed by bisulfite sequencing in human glioblastoma tissues with abundant CD133 mRNA. Taken together, our results indicate that DNA hypomethylation is an important determinant of CD133 expression in glioblastomas, and this epigenetic event may be associated with the development of BTICs expressing CD133.