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.

A stability evaluation method for deep-seated toppling in the upper Lancang river,Southwestern China

Deep-seated toppling in the upper reaches of the Lancang River,southwest China involves deformations exceeding 100 m in depth.The slope deformation is initiated by river downcutting and evolves distinctive characteristics with a depth of river incision.In this study,we propose a system for evaluating the stability of deep-seated toppled slopes in different evolutionary stages.This system contains identification criteria for each evolutionary stage and provides the corresponding stability evaluation methods.Based on the mechanical and kinematic analysis of slope blocks,the specific stage of slope movement can be identified in the field through outcrop mapping,in situ tests,surface displacement monitoring,and adit and borehole explorations.The stability evaluation methods are established based on the limiting equilibrium theory and the strain compatibility between the undisturbed zone and the toppled zone.Finally,several sample slopes in different evolution stages have been investigated to verify the applicability and accuracy of the proposed stability evaluation system.The results indicate that intense tectonic activity and rapid river incision lead to a maximum principal stress ratio exceeding 10 near the slope surface,thus triggering widespread toppling deformations along the river valley.When considering the losses of joint cohesion during the further rotation process,the safety factor of the slope drops by 7%e28%.The self-stabilization of toppling deformation can be recognized by the layer symmetry configuration after the free rotation of the deflected layers.Intensely toppled rock blocks mainly suffer sliding failures beyond the layer symmetry condition.The factor of safety of the K73 rockslide decreased from 1.17 to 0.87 by considering the development of the potential sliding surface and the toesaturated zone.

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.

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.

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).

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.

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.

Geophysical-Geological Interpretation and Deep-Seated Gold Deposit Prospecting in Sanshandong-Jiaojia Area, Eastern Shandong Province, China

Integrated gravitational, electrical-magnetic surveys and data processing carried out in the Sanshandao-Jiaojia area, Eastern Shandong Province, northeast China, aim to illuminate the geological characteristics of this shallow-covered area and delineate deep-seated gold prospecting targets. In this region, altogether 12 faults exert critical control on distribution of three types of Early Precambrian metamorphic rock series, i.e. those in the metamorphic rock area, in the granitic rock area underlying the metamorphic rock, and in the remnant metamorphic rock area in granites, respectively. Additionally, the faults have major effects on distribution of four Mesozoic Linglong rock bodies of granite, i.e. the Cangshang, Liangguo, Zhuqiao-Miaojia and Jincheng granites. The Sanshandao and Jiaojia Faults are two well-known regional ore-controlling faults; they have opposite dip direction, and intersect at a depth of 4500 m. Fracture alteration zones have striking geophysical differences relative to the surrounding county rocks. The two faults extend down along dip direction in a gentle wave form, and appear at some steps with different dips. These steps comprise favorable gold prospecting areas, consistent with a step metallogenic model. Six deep-seated gold-prospecting targets are delineated, i.e. Jincheng-Qianchenjia, Xiaoxizhuang-Zhaoxian, Xiyou-Wujiazhuangzi, Xiangyangling-Xinlicun, Panjiawuzi and Miaojia-Pinglidian.

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.

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.

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.

Magnetic resonance imaging characteristics of postoperative intracranial dissemination of recurrent gliomas

Ten intracranial gliomas cases, that had postoperative intracranial dissemination, underwent magnetic resonance imaging （MRI） examinations, including T1 weighted imaging, fat-suppressed T1 weighted imaging, T2 weighted imaging and fluid attenuated inversion recovery （FLAIR）. Results showed that tumor metastasis had occurred via the cerebrospinal fluid, the brain white matter fibers and the surgical access site alone. On the plain MRI scans, 1/7 cases were linearly thickened with isointensity and 5/7 cases exhibited nodular foci on T1 weighted imaging; the cerebral sulci and cisterns in 2/7 cases had become shallow and five cases had nodular foci on T2 weighted imaging. FLAIR imaging revealed that the cerebral sulci and cisterns in 2/7 cases had become shallow and that six cases had affected nodular foci. The contrast-enhanced MRI scans revealed linear thickening in seven cases, nodules in seven cases, similarities to ＂mould-like＂ signs in six cases and hydrocephalus in six cases. These findings suggested that MRI with different sequences can diagnose glioma metastasis.

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.

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.

The relationship between the expression of tumor matrix-metalloproteinase and the characteristics of magnetic resonance imaging of human gliomas

Objective： To investigate the relationship between the expression level of matrix-metalloproteinases （MMPs） with the pathological grades and MRI characteristics of human gliomas. Methods： Prior pre- and post-contrast enhancement MRI was performed on 31 patients with gliomas, which were confirmed by post-operational pathology. The expression of MMP-2 and MMP-9 were determined by immunohistochemical staining in both a low grading group （grades I and II, n = 20） and high grading group （grades III and IV, n = 11）. Results： Compared to the low grading group, the expression levels of MMP-2, MMP-9, as well as the tumor edema index （EI）, enhanced percentage （EP） and maximum diameters were significantly greater in the high grading group. MMP-2 and MMP-9 expression were correlated with the tumor EI, EP and the maximum diameters. There were no differences in MMP-2 and MMP-9 expression between the unclear border definition group and the clear border definition group, whereas the MMPs expression levels were greater in the heterogeneous signal group than in the homogeneous signal group. Conclusion： The expression level of MMPs is correlated with the invasion ability of human gliomas. The MRI parameters, such as tumor El, EP, maximum diameter, and signal heterogeneity technically reflect the expression level of MMPs, and can be used to estimate the tumor＇s malignant behavior, thus providing the guidance for clinical therapies.

Numerical modeling of deep-seated landslides interacting with man-made structures

This paper describes the interaction between deep-seated landslides and man-made structures such as dams, penstocks, viaducts, and tunnels. Selected case studies are reported first with the intent to gain insights into the complexities associated with the interaction of these structures with deep-seated landslides(generally referred to as deep-seated gravity slope deformations, DSGSDs). The main features, which characterize these landslides, are mentioned together with the interaction problems encountered in each case. Given the main objective of this paper, the numerical modeling methods adopted are outlined as means for increase in the understanding of the interaction problems being investigated. With the above in mind, the attention moves to an important and unique case history dealing with the interaction of a large-size twin-tunnel excavated with an earth pressure balance(EPB)tunnel boring machine(TBM) and a deep-seated landslide, which was reactivated due to the stress changes induced by tunnel excavation in landslide shear zone. The geological and geotechnical conditions are described together with the available monitoring data on the landslide movements, based on the advanced and conventional monitoring tools used. Numerical modeling is illustrated as an aid to back-analyze the monitored surface and subsurface deformations and to assist in finding the appropriate engineering solution for putting the tunnel into service and as a follow-up means for future understanding and control of the interaction problems. The simulation is based on a novel time-dependent model representing the landslide behavior.

Re-irradiation for high-grade gliomas:Has anything changed?

Optimal management after recurrence or progression of high-grade gliomas is still undefined and remains a challenge for neuro-oncology multidisciplinary teams.Improved radiation therapy techniques,new imaging methods,published experience,and a better radiobiological knowledge of brain tissue have positioned re-irradiation(re-RT)as an option for many of these patients.Decisions must be individualized,taking into account the pattern of relapse,previous treatment,and functional status,as well as the patient’s preferences and expected quality of life.Many questions remain unanswered with respect to re-RT:Who is the most appropriate candidate,which dose and fractionation are most effective,how to define the target volume,which imaging technique is best for planning,and what is the optimal timing?This review will focus on describing the most relevant studies that include re-RT as salvage therapy,with the aim of simplifying decision-making and designing the best available therapeutic strategy.

Photodynamic Therapy Mediated by 5-Aminolevulinic Acid Suppresses Gliomas Growth by Decreasing the Microvessels

Although 5-aminolevulinic acid（5-ALA）-mediated photodynamic therapy（PDT） has been demonstrated to be a novel and effective therapeutic modality for some human malignancies, its effect and mechanism on glioma are still controversial. Previous studies have reported that 5-ALA-PDT induced necrosis of C6 rat glioma cells in vitro. The aim of this study was to further investigate the effect and mechanism of 5-ALA-PDT on C6 gliomas implanted in rats in vivo. Twenty-four rats bearing similar size of subcutaneously implanted C6 rat glioma were randomly divided into 3 groups： receiving 5-ALA-PDT（group A）, laser irradiation（group B）, and mock procedures but without any treatment（group C）, respectively. The growth, histology, microvessel density（MVD）, and apoptosis of the grafts in each group were determined after the treatments. As compared with groups B and C, the volume of tumor grafts was significantly reduced（P〈0.05）, MVD was significantly decreased（P〈0.001）, and the cellular necrosis was obviously increased in group A. There was no significant difference in apoptosis among the three groups. The in vivo studies confirmed that 5-ALA-PDT may be an effective treatment for gliomas by inhibiting the tumor growth. The mechanism underlying may involve increasing the cellular necrosis but not inducing the cellular apoptosis, which may result from the destruction of the tumor microvessels.