To investigate the inhibitory effect and anti-cancer mechanism of adenovirus mediated IL-24 gene expression on the human U251 glioma cell. U251 glioma cells were infected with Ad-IL-24 at various multiplicity of infection (MOIs). Cell proliferation was determined by MTT assay. Cell apoptosis was detected by flow cytometry and Hochest staining. The transcription of apoptosis-related genes was analyzed by reverse transcription-PCR (RT-PCR), and the expression of Cleaved Caspase-3 was analyzed by Western blotting. The result showed that the growth of U251 glioma cells was significantly inhibited by Ad-IL-24 at the MOI of 100. The apoptotic rate of U251 glioma cells was 42% 72 h after infection with Ad-IL-24. Four days after infection, the growth of the U251 glioma cells was inhibited to 50%. RT-PCR showed that Ad-IL-24 not only up-regulated expression of bax/bcl-2, ICE, C-myc, p53 and down-regulated the expression of HIF-1alpha, but also enhanced Caspase-3 activation, eventually resulting apoptosis. Taken together, these results suggest that infection of U251 glioma cells with Ad-IL-24 can inhibit growth and induce apoptosis significantly by the regulation of apoptosis-related genes.
Adenoviridae ; genetics ; metabolism ; Apoptosis ; Brain Neoplasms ; genetics ; pathology ; Cell Proliferation ; drug effects ; Genetic Therapy ; Glioma ; genetics ; pathology ; Humans ; Interleukins ; genetics ; metabolism ; Recombination, Genetic ; Tumor Cells, Cultured

At this time, brain tumor stem cells remain a controversial hypothesis while malignant brain tumors continue to present a dire prognosis of severe morbidity and mortality. Yet, brain tumor stem cells may represent an essential cellular target for glioma therapy as they are postulated to be the tumorigenic cells responsible for recurrence. Targeting oncogenic pathways that are essential to the survival and growth of brain tumor stem cells represents a promising area for developing therapeutics. However, due to the multiple oncogenic pathways involved in glioma, it is necessary to determine which pathways are the essential targets for therapy. Furthermore, research still needs to comprehend the morphogenic processes of cell populations involved in tumor formation. Here, we review research and discuss perspectives on models of glioma in order to delineate the current issues in defining brain tumor stem cells as therapeutic targets in models of glioma.
1-Phosphatidylinositol 3-Kinase/genetics/metabolism ; Animals ; Brain Neoplasms/genetics/*metabolism/*pathology/therapy ; Glioma/genetics/*metabolism/*pathology/therapy ; Humans ; Neoplastic Stem Cells/*metabolism/*pathology ; Receptors, Notch/genetics/metabolism ; Signal Transduction/genetics/physiology

Malignant glioma is the most frequent type in brain tumors. The prognosis of this tumor has not been significantly improved for the past decades and the average survival of patients is less than one year. Thus, an effective novel therapy is urgently needed. TNF-related apoptosis inducing ligand (TRAIL), known to have tumor cell-specific killing activity, has been investigated as a novel therapeutic for cancers. We have developed Ad-stTRAIL, an adenovirus delivering secretable trimeric TRAIL for gene therapy and demonstrated the potential to treat malignant gliomas. Currently, this Ad-stTRAIL gene therapy is under phase I clinical trial for malignant gliomas. Here, we report preclinical studies for Ad-stTRAIL carried out using rats. We delivered Ad-stTRAIL intracranially and determined its pharmacokinetics and biodistribution. Most Ad-stTRAIL remained in the delivered site and the relatively low number of viral genomes was detected in the opposite site of brain and cerebrospinal fluid. Similarly, only small portion of the viral particles injected was found in the blood plasma and major organs and tissues, probably due to the brain-blood barrier. Multiple administrations did not lead to accumulation of Ad-stTRAIL at the injection site and organs. Repeated delivery of Ad-stTRAIL did not show any serious side effects. Our data indicate that intracranially delivered Ad-stTRAIL is a safe approach, demonstrating the potential as a novel therapy for treating gliomas.
Adenoviridae/genetics ; Animals ; Blood-Brain Barrier ; Brain/drug effects/*metabolism/pathology ; Brain Neoplasms/genetics/metabolism/pathology/*therapy ; Clinical Trials, Phase I as Topic ; DNA, Viral/metabolism ; Disease Models, Animal ; Drug Delivery Systems ; Drug Evaluation, Preclinical ; *Gene Therapy ; Glioma/genetics/metabolism/pathology/*therapy ; Humans ; Liver/drug effects/metabolism/pathology ; Protein Multimerization/genetics ; Rats ; Spleen/drug effects/metabolism/pathology ; TNF-Related Apoptosis-Inducing Ligand/genetics/*pharmacokinetics

Malignant glioma is the most frequent type in brain tumors. The prognosis of this tumor has not been significantly improved for the past decades and the average survival of patients is less than one year. Thus, an effective novel therapy is urgently needed. TNF-related apoptosis inducing ligand (TRAIL), known to have tumor cell-specific killing activity, has been investigated as a novel therapeutic for cancers. We have developed Ad-stTRAIL, an adenovirus delivering secretable trimeric TRAIL for gene therapy and demonstrated the potential to treat malignant gliomas. Currently, this Ad-stTRAIL gene therapy is under phase I clinical trial for malignant gliomas. Here, we report preclinical studies for Ad-stTRAIL carried out using rats. We delivered Ad-stTRAIL intracranially and determined its pharmacokinetics and biodistribution. Most Ad-stTRAIL remained in the delivered site and the relatively low number of viral genomes was detected in the opposite site of brain and cerebrospinal fluid. Similarly, only small portion of the viral particles injected was found in the blood plasma and major organs and tissues, probably due to the brain-blood barrier. Multiple administrations did not lead to accumulation of Ad-stTRAIL at the injection site and organs. Repeated delivery of Ad-stTRAIL did not show any serious side effects. Our data indicate that intracranially delivered Ad-stTRAIL is a safe approach, demonstrating the potential as a novel therapy for treating gliomas.
Adenoviridae/genetics ; Animals ; Blood-Brain Barrier ; Brain/drug effects/*metabolism/pathology ; Brain Neoplasms/genetics/metabolism/pathology/*therapy ; Clinical Trials, Phase I as Topic ; DNA, Viral/metabolism ; Disease Models, Animal ; Drug Delivery Systems ; Drug Evaluation, Preclinical ; *Gene Therapy ; Glioma/genetics/metabolism/pathology/*therapy ; Humans ; Liver/drug effects/metabolism/pathology ; Protein Multimerization/genetics ; Rats ; Spleen/drug effects/metabolism/pathology ; TNF-Related Apoptosis-Inducing Ligand/genetics/*pharmacokinetics

OBJECTIVETo investigate the effects of leucine-rich repeats and immunoglobulin-like domains 3 (LRIG3) on the biological activity of glioblastoma cell line GL15.

METHODSGlioblastoma GL15 cells were cultured and transfected with LRIG3-EGFP plasmid. The location of LRIG3 in GL15 cells was observed with confocal microscopy. The proliferation and invasiveness of GL15 cells were detected with methyl thiazolyl tetrazolium (MTT) and Transwell methods respectively; the expression of epidermal growth factor receptor (EGFR) and LRIG3 mRNA and protein were detected with reverse transcriptase-polymerase chain reaction (RT-PCR) and Western blot respectively.

RESULTAfter transfection with the plasmid LRIG-EGFP, LRIG3 fusion protein was found in cytoplasm of GL15 cells and cell proliferative and invasiveness were reduced. The expression of EGFR and LRIG3 varied with the duration of EGF treatment (100 ng/ml): the expression of EGFR decreased while the expression of LRIG3 increased as time prolonged.

CONCLUSIONLRIG3 can inhibit the proliferation and invasiveness of glioblastoma cells and may be used as a target gene in gene therapy of glioblastoma.

Brain Neoplasms ; pathology ; Cell Proliferation ; Epidermal Growth Factor ; genetics ; Glioblastoma ; pathology ; Humans ; Membrane Proteins ; genetics ; metabolism ; Neoplasm Invasiveness ; Plasmids ; genetics ; RNA, Messenger ; genetics ; metabolism ; Receptor, Epidermal Growth Factor ; genetics ; metabolism ; Recombinant Fusion Proteins ; genetics ; metabolism ; Transfection ; Tumor Cells, Cultured

OBJECTIVETo study the role of survivin gene in the invasive behavior of glioma cells and explore the possible mechanism.

METHODSThe mRNA and protein expressions of survivin in glioma cell line SNB19 transfected by small interfering RNA (siRNA) targeting survivin were determined by real time RT-PCR and Western blotting, respectively. The anchorage-independent growth of the cells was examined by clone formation assay in soft agar, and their invasiveness was evaluated using a Boyden chamber model. The protein level of urokinase-type plasminogen activator (uPA) was also determined by western blotting.

RESULTSSurvivin siRNA dose-dependently inhibited the anchorage-independent growth and invasiveness and reduced the expression of uPA protein in SNB19 cells.

CONCLUSIONRNA interference targeting survivin can inhibit the invasiveness of glioma cells in vitro possibly by down-regulating uPA expression.

Brain Neoplasms ; genetics ; pathology ; Cell Line, Tumor ; Glioma ; genetics ; pathology ; Humans ; Inhibitor of Apoptosis Proteins ; Microtubule-Associated Proteins ; genetics ; metabolism ; Neoplasm Invasiveness ; genetics ; RNA Interference ; RNA, Messenger ; genetics ; metabolism ; RNA, Small Interfering ; genetics ; Urokinase-Type Plasminogen Activator ; genetics ; metabolism

OBJECTIVETo study the expression of RAS protein in human glioma tissues and its influence on tumor growth.

METHODSRAS protein expression in glioma tissues was determined by immunohistochemical (IHC) staining. Subsequently, MTT cell proliferation assay, flow cytometry and Western blotting were used to assay U251 cells with reduced RAS expression.

RESULTSThe expression of RAS in glioma was increased and strongly correlated with pathological grade. Downregulation of RAS resulted in glioma cells growth suppression and increased apoptosis.

CONCLUSIONThe expression level of RAS protein in human glioma was increased. Downregulation of RAS can inhibit glioblastoma cell growth through the RAS signal pathway.

Brain Neoplasms ; genetics ; metabolism ; pathology ; Cell Growth Processes ; genetics ; Cell Line, Tumor ; Down-Regulation ; Glioma ; genetics ; pathology ; Humans ; Immunohistochemistry ; ras Proteins ; biosynthesis ; genetics

Astrocytoma ; genetics ; metabolism ; pathology ; Brain Neoplasms ; classification ; genetics ; metabolism ; pathology ; Child ; Child, Preschool ; Chromosomal Proteins, Non-Histone ; genetics ; metabolism ; Chromosome Deletion ; Cyclin-Dependent Kinase Inhibitor p16 ; genetics ; metabolism ; DNA-Binding Proteins ; genetics ; metabolism ; Ependymoma ; genetics ; metabolism ; pathology ; Hedgehog Proteins ; genetics ; metabolism ; Humans ; Medulloblastoma ; classification ; genetics ; metabolism ; pathology ; Proto-Oncogene Proteins B-raf ; genetics ; metabolism ; Rhabdoid Tumor ; genetics ; metabolism ; pathology ; SMARCB1 Protein ; Signal Transduction ; Transcription Factors ; genetics ; metabolism ; Wnt Proteins ; metabolism ; beta Catenin ; genetics ; metabolism

OBJECTIVEOur previous cDNA array data have shown that expression level of CDK1 increased along with the malignant progression of ganglioglioma, and decreased with the differentiation process of neural stem cells. The purpose of this study was to investigate the CDK1 expression levels in gliomas and the effects of CDK1 knockdown on phenotype of glioma cells.

METHODSGlioma tissue array was constructed, which was composed of surgical specimens of gliomas with different malignancy grades, glioma xenografts in nude mice, cellular spheroids of brain tumor stem cells, normal neural stem cells and glioma cell line. CDK1 expression was detected in glioma tissue array with immunohistochemical techniques. CDK1 expression in human brain glioma cell line and relevant xenogeneic graft tumor was inhibited by retroviral vectors expressing short hairpin RNAs (shRNAs). Both in vitro and in vivo changes of biological characteristics were further observed.

RESULTSThe expression level of CDK1 increased along with the malignancy progression of glioma in clinical specimens. The positive expression rates of CDK1 in human brain glioma tissues were 22.2% (grade I), 40.0% (grade II), 69.6% (grade III) and 78.6% (grade IV), P = 0.01, respectively. The positive expression rate of CDK1 in glioma cell line and implanted xenografts was similar as the clinical tumors with high malignancy, and higher than those in neural stem cells and brain tumor stem cells (P = 0.0014). Expression of CDK1 was high in human fetal brain tissues and bone marrows of nude mice, but low in normal adult human brain tissues. Downregulation of CDK1 inhibited the proliferation activities notably both in SHG-44 cells in vitro and relevant xenogeneic graft tumors, and induced apoptosis of tumor cells prominantly as well.

CONCLUSIONOverexpression of CDK1 may promote oncogenesis and progression of human gliomas. Downregulation of CDK1 expression can inhibit the proliferation activities of human malignant gliomas.

Animals ; Apoptosis ; drug effects ; Astrocytoma ; genetics ; metabolism ; pathology ; Brain Neoplasms ; genetics ; metabolism ; pathology ; Brain Stem Neoplasms ; metabolism ; CDC2 Protein Kinase ; genetics ; metabolism ; Cell Cycle ; drug effects ; Cell Differentiation ; drug effects ; Cell Line, Tumor ; Ganglioglioma ; genetics ; metabolism ; pathology ; Gene Expression Regulation, Neoplastic ; Gene Silencing ; Glioma ; genetics ; metabolism ; pathology ; Humans ; Mice ; Mice, Nude ; Neoplasm Staging ; Neoplasm Transplantation ; RNA, Messenger ; metabolism

The current World Health Organization classification system of primary brain tumors is solely based on morphologic criteria. However, there is accumulating evidence that tumors with similar histology have distinct molecular signatures that significantly impact treatment response and survival. Recent practice-changing clinical trials have defined a role for routine assessment of O-6-methylguanine-DNA methyltransferase (MGMT) promoter methylation in glioblastoma patients, especially in the elderly, and 1p and 19q codeletions in patients with anaplastic glial tumors. Recently discovered molecular alterations including mutations in IDH-1/2, epidermal growth factor receptor (EGFR), and BRAF also have the potential to become targets for future drug development. This article aims to summarize current knowledge on the molecular biology of high-grade gliomas relevant to daily practice.
Aged ; Brain Neoplasms ; genetics ; metabolism ; pathology ; Chromosome Deletion ; DNA Methylation ; DNA Modification Methylases ; genetics ; metabolism ; DNA Repair Enzymes ; genetics ; metabolism ; Glioblastoma ; genetics ; metabolism ; pathology ; Glioma ; genetics ; metabolism ; pathology ; Humans ; Isocitrate Dehydrogenase ; genetics ; metabolism ; Neoplasm Grading ; Oligodendroglioma ; genetics ; metabolism ; pathology ; Point Mutation ; Promoter Regions, Genetic ; Receptor, Epidermal Growth Factor ; metabolism ; Tumor Suppressor Proteins ; genetics ; metabolism