To evaluate the effect of wild-type p53 gene on the growth and radiotherapeutic sensitivity of human glioma cells, plasmid PC53-SN3 carrying wild-type p53 gene was transfected into U251 cells. p53 gene expression in transfected cells was detected by RT-PCR, and the cell growth inhibition and apoptosis in the absence or presence of irradiation were assessed by MTT and flow cytometry. The transfection of p53 gene into U251 cells was confirmed by RT-PCR. MTT showed that p53 gene alone induced strong inhibitory effect on the growth of U251 cells (inhibition rate (IR), (79.60 +/- 5.69)%). The killing effect of irradiation alone on U251 cells was not strong (IR: (17.06 +/- 4.35)% (17.39 +/- 1.67)% (18.73 +/- 4.68)%) and increased with the irradiation doses (3, 6, 9 Gy). When combined treatment of wild-type p53 gene transfection and irradiation was used, the effect was significantly increased (IR:(80.60 +/- 5.35)%. (90.30 +/- 1.67)%, (91.30 +/- 2.01)%). The apoptosis rate of U251 cells induced by p53 gene transfection was 17.38%. The rate induced by irradiation increased (4.61%, 4.84%, 5.40%) with the irradiation doses (3, 6, 9 Gy). The apoptosis rate was also significantly increased (17.80%, 20.03%, 22.34%) after combined treatment of p53 and irradiation with different doses (3, 6, 9 Gy). It is concluded that wild-type p53 gene and irradiation could result in synergistic inhibitory effect on the growth of human glioma cells.
Apoptosis/*radiation effects ; Brain Neoplasms/genetics ; Brain Neoplasms/*pathology ; Genes, p53/*radiation effects ; Glioma/genetics ; Glioma/*pathology ; Transfection ; Tumor Cells, Cultured

The expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF)2 in the irradiated brain was examined to test how a single high dose radiation, similar to that used for intraoperative radiation therapy given to the normal cerebrum, can affect the vascular endothelium. After a burr hole trephination in the rat skull, the cerebral hemisphere was exposed to a single 10 Gy dose of gamma rays, and the radiation effect was assessed at 1, 2, 4, 6, and 8 weeks after irradiation. His-tological changes, such as reactive gliosis, inflammation, vascular proliferation and necrosis, were correlated with the duration after irradiation. Significant VEGF and FGF2 expression in the 2- and 8-week were detected by enzyme-linked immunosorbent assay quantification in the radiation group. Immunohistochemical study for VEGF was done and the number of positive cells gradually increased over time, compared with the sham operation group. In conclusion, the radiation injuries consisted of radiation necrosis associated with the expression of VEGF and FGF2. These findings indicate that VEGF and FGF2 may play a role in the radiation injuries after intraoperative single high-dose irradiation.
Animals ; Brain/metabolism/pathology/radiation effects ; Brain Injuries/etiology/*metabolism/*pathology ; Fibroblast Growth Factor 2/*metabolism ; Necrosis ; Radiation Injuries/*pathology ; Radiosurgery/*adverse effects ; Rats ; Rats, Sprague-Dawley ; Up-Regulation/radiation effects ; Vascular Endothelial Growth Factor A/*metabolism

OBJECTIVETo investigate the effect of handportable mobiletelephone microwave radiation on rat central nervous system by setting up rat model.

METHODS80 healthy male SD rats (weighed about 200 g) were divided into 4 groups at random: control, radiation, decranium, decranium + radiation. TUNEL method was adopted used to detect the apoptosis of neurons after irradiation, then immunohistochemistry was used to detect Bcl-2, Bax expression in all brain tissue.

RESULTSTUNEL positive rate, Bax and Bcl-2 positive cell numbers could be found in decranium + radiation group [(26.45 +/- 9.27)%, (23.5 +/- 3.58), (11.1 +/- 2.55) respectively]. There were significant differences among control [(9.59 +/- 2.55)%, 14.2 +/- 2.46, 7.0 +/- 1.14 respectively], decranium group [(9.52 +/- 1.93)%, 15.5 +/- 1.77, 7.4 +/- 1.76], radiation group [(10.04 +/- 3.62)%, 15.9 +/- 2.02, 7.2 +/- 1.07] (P < 0.01). But the difference was not found in the ratio of Bax to Bcl-2.

CONCLUSIONMicrowave radiation did not affect the intact rat, but did promote the occurrence of neuron apoptosis in cranial defect rat. Bax, Bcl-2 gene participated in regulation of apoptosis. The intact cranium may be an important factor to protect the neurons against handportable mobiletelephone microwave radiation to some extent.

Animals ; Apoptosis ; radiation effects ; Brain ; pathology ; radiation effects ; In Situ Nick-End Labeling ; Male ; Microwaves ; adverse effects ; Neurons ; pathology ; radiation effects ; Proto-Oncogene Proteins ; analysis ; Proto-Oncogene Proteins c-bcl-2 ; analysis ; Rats ; Rats, Sprague-Dawley ; bcl-2-Associated X Protein

Even though there is no direct evidence to prove the cellular and molecular changes induced by radiofrequency (RF) radiation itself, we cannot completely exclude the possibility of any biological effect of mobile phone frequency radiation. We established a carousel-type exposure chamber for 849 MHz or 1763 MHz of mobile phone RF radiation to expose RF to the heads of C57BL mice. In this chamber, animals were irradiated intermittently at 7.8 W/kg for a maximum of 12 months. During this period, the body weights of 3 groups-sham, 849 MHz RF, and 1763 MHz RF-did not show any differences between groups. The brain tissues were obtained from 3 groups at 6 months and 12 months to examine the differences in histology and cell proliferation between control and RF exposure groups, but we could not find any change upon RF radiation. Likewise, we could not find changes in the expression and distribution of NeuN and GFAP in hippocampus and cerebellum, or in cell death by TUNEL assay in RF exposure groups. From these data, we conclude that the chronic exposure to 849 MHz and 1763 MHz RF radiation at a 7.8 W/kg specific absorption rate (SAR) could not induce cellular alterations such as proliferation, death, and reactive gliosis.
Animals ; Apoptosis/*radiation effects ; Body Weight/radiation effects ; Brain/pathology/*radiation effects ; Cell Proliferation/*radiation effects ; *Cellular Phone ; Dose-Response Relationship, Radiation ; Gliosis/etiology/pathology ; In Situ Nick-End Labeling ; Mice ; Mice, Inbred C57BL ; Nerve Tissue Proteins/biosynthesis/genetics ; Proliferating Cell Nuclear Antigen/biosynthesis/genetics ; Radio Waves/*adverse effects

The extracellular matrix metalloproteinase inducer (EMMPRIN) has been known to play a key regulatory role in pathological angiogenesis. A elevated activation of vascular endothelial growth factor (VEGF) following radiation injury has been shown to mediate blood-brain barrier (BBB) breakdown. However, the roles of EMMPRIN and VEGF in radiation-induced brain injury after gamma knife surgery (GKS) are not clearly understood. In this study, we investigated EMMPRIN changes in a rat model of radiation injury following GKS and examined potential associations between EMMPRIN and VEGF expression. Adult male rats were subjected to cerebral radiation injury by GKS under anesthesia. We found that EMMPRIN and VEGF expression were markedly upregulated in the target area at 8-12 weeks after GKS compared with the control group by western blot, immunohistochemistry, and RT-PCR analysis. Immunofluorescent double staining demonstrated that EMMPRIN signals colocalized with caspase-3 and VEGF-positive cells. Our data also demonstrated that increased EMMPRIN expression was correlated with increased VEGF levels in a temporal manner. This is the first study to show that EMMPRIN and VEGF may play a role in radiation injuries of the central nervous system after GKS.
Animals ; Antigens, CD147/*metabolism ; Brain/blood supply/metabolism/pathology/*radiation effects ; Brain Injuries/metabolism/pathology ; Caspase 3/metabolism ; Gamma Rays/*adverse effects ; Immunohistochemistry ; Male ; Microscopy, Electron, Transmission ; Parietal Lobe/metabolism/pathology/radiation effects ; Radiation Injuries, Experimental/metabolism ; Radiosurgery/adverse effects ; Rats ; Rats, Wistar ; Time Factors ; Vascular Endothelial Growth Factor A/*metabolism

Tumor cell proliferation, infiltration, migration, and neovascularization are known causes of treatment resistance in glioblastoma multiforme (GBM). The purpose of this study was to determine the effect of radiation on the growth characteristics of primary human GBM developed in a nude rat. Primary GBM cells grown from explanted GBM tissues were implanted orthotopically in nude rats. Tumor growth was confirmed by magnetic resonance imaging on day 77 (baseline) after implantation. The rats underwent irradiation to a dose of 50 Gy delivered subcuratively on day 84 postimplantation (n = 8), or underwent no radiation (n = 8). Brain tissues were obtained on day 112 (nonirradiated) or day 133 (irradiated). Immunohistochemistry was performed to determine tumor cell proliferation (Ki-67) and to assess the expression of infiltration marker (matrix metalloproteinase-2, MMP-2) and cell migration marker (CD44). Tumor neovascularization was assessed by microvessel density using von-Willebrand factor (vWF) staining. Magnetic resonance imaging showed well-developed, infiltrative tumors in 11 weeks postimplantation. The proportion of Ki-67-positive cells in tumors undergoing radiation was (71 +/- 15)% compared with (25 +/- 12)% in the nonirradiated group (P = 0.02). The number of MMP-2-positive areas and proportion of CD44-positive cells were also high in tumors receiving radiation, indicating great invasion and infiltration. Microvessel density analysis did not show a significant difference between nonirradiated and irradiated tumors. Taken together, we found that subcurative radiation significantly increased proliferation, invasion, and migration of primary GBM. Our study provides insights into possible mechanisms of treatment resistance following radiation therapy for GBM.
Animals ; Brain Neoplasms ; metabolism ; pathology ; radiotherapy ; Cell Line, Tumor ; Cell Movement ; radiation effects ; Cell Proliferation ; radiation effects ; Female ; Glioblastoma ; metabolism ; pathology ; radiotherapy ; Humans ; Hyaluronan Receptors ; metabolism ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Magnetic Resonance Imaging ; Matrix Metalloproteinase 2 ; metabolism ; Microvessels ; pathology ; Neoplasm Transplantation ; Neovascularization, Pathologic ; pathology ; Radiation Tolerance ; Radiotherapy, High-Energy ; Rats ; Rats, Nude

Cytokines and growth factors are important regulatory proteins controlling the growth and differentiation of normal and malignant glial cells. In this study, we investigated the expression and origin of tumor necrosis factor-alpha (TNF-alpha) and transforming growth factor-beta 1 (TGF-beta 1) in the subacute brain injury after a single high-dose irradiation using 60 Sprague-Dawley rats. The right cerebral hemispheres of rats were exposed to a single 10 Gy dose of gamma rays using Ir-192. The radiation effect was assessed at 1 week, 2 weeks, 4 weeks, 6 weeks, and 8 weeks after irradiation, and the results were compared with those in sham operation group. Histological changes characteristic of radiation injury were correlated with the duration after the single dose irradiation. The loss of cortical thickness also increased with the lapse of time after irradiation. The TNF-alpha expression in the irradiated cerebral hemispheres was significantly increased compared with that in the sham operation group. TGF-beta 1 expression was also increased in the irradiated hemispheres. Immunohistochemical study revealed that TGF-beta 1 was expressed predominantly by infiltrating macrophages and astrocytes around the necrotic areas. These findings indicate that TNF-alpha and TGF-beta 1 may play prominent roles in the radiation injuries after a single high-dose irradiation.
Animals ; Brain/immunology/pathology/*radiation effects ; Dose-Response Relationship, Radiation ; Immunohistochemistry/methods ; Rats ; Rats, Sprague-Dawley ; Time Factors ; Transforming Growth Factor beta/*biosynthesis ; Transforming Growth Factor beta1 ; Tumor Necrosis Factor-alpha/*biosynthesis

BACKGROUNDConventional treatment for non-small cell lung cancer (NSCLC) brain metastases (BM) is whole-brain radiotherapy (WBRT). The efficacy is limited. It might be increased by a potent radiosensitizer such as gemcitabine, which is believed to cross the disrupted blood-brain barrier. The primary objective of this study was to determine the maximum tolerated dose (MTD) of weekly gemcitabine given concurrently with WBRT.

METHODSPatients with BM from NSCLC were included. The dose of WBRT was 3750 cGy (total 15 times, 3 weeks). Gemcitabine was given concurrently with WBRT on days 1, 8 and 15. The starting dose was 400 mg/m(2), escalated by 100 mg/m(2) increments. At least three patients were included per level. Dose limiting toxicity (DLT) was defined as grade 4 hematological or grade 2 neurological toxicity. When two or more patients experience DLT, the MTD was reached.

RESULTSA total of 16 patients were included; 69% had a performance status (PS) 1 (Eastern Cooperative Oncology Group, ECOG). A total of 69% had concurrent active extra cranial diseases. All had more than 3 BM. Up to 600 mg/m(2) (level 3) no neurology toxicity was observed. At 600 mg/m(2) two out of 9 patients developed grade 4 thrombocytopenia. One of the two patients' thrombocytopenia was confused with disseminated intravascular coagulation (DIC). At 700 mg/m(2) two out of 4 patients developed neurotoxicities. One developed grade 3 seizure and cognitive disorder. Another patient developed suspected grade 2 muscle weakness.

CONCLUSIONSThe MTD was reached at a dose of 700 mg/m(2). The dose of 600 mg/m(2) would be considered for further study.

Aged ; Brain Neoplasms ; radiotherapy ; secondary ; Carcinoma, Non-Small-Cell Lung ; pathology ; Cranial Irradiation ; Deoxycytidine ; administration & dosage ; adverse effects ; analogs & derivatives ; pharmacokinetics ; Female ; Humans ; Lung Neoplasms ; pathology ; Male ; Maximum Tolerated Dose ; Middle Aged ; Radiation-Sensitizing Agents ; administration & dosage

Monitoring the long-term radiotherapy-associated molecular changes in low-grade gliomas (LGGs) facilitates the understanding of LGG response to radiotherapy. In this study, we used immunohistochemistry to analyze the expression of Ki-67, tumor protein P53 (TP53), P21, and P27 in 8 paired WHO grade II astrocytoma samples. The interval between radiotherapy (RT) and the second surgery was more than 3 months in all cases. The average Ki-67 labeling index (LI) was 5.3% in pre-RT samples and 11.54% in post-RT samples. Ki-67 LI was higher in the primary tumors that underwent malignant transformation observed at the second surgery after radiation. Post-RT Ki-67 LI decreased in 2 cases with an interval of less than 12 months between RT and the second surgery. TP53 expression was found in 3 out of 4 pre-RT samples with malignant transformation and in 1 out of 4 pre-RT samples without malignant transformation. Post-RT TP53 increased in 2 cases in which increased expression of P21 or P27 was also observed. Our study suggests that radiotherapy can inhibit WHO grade II astrocytoma proliferation as reflected by Ki-67 LI, but the effect attenuates with time. In addition, there is a tendency of malignant transformation for WHO grade II astrocytomas with a high Ki-67 level or TP53 expression in initial samples.
Adult ; Astrocytoma ; metabolism ; pathology ; radiotherapy ; surgery ; Brain Neoplasms ; metabolism ; pathology ; radiotherapy ; surgery ; Cell Proliferation ; radiation effects ; Cell Transformation, Neoplastic ; radiation effects ; Cyclin-Dependent Kinase Inhibitor p21 ; metabolism ; Cyclin-Dependent Kinase Inhibitor p27 ; metabolism ; Female ; Humans ; Immunohistochemistry ; Ki-67 Antigen ; metabolism ; Male ; Middle Aged ; Neoplasm Grading ; Tumor Suppressor Protein p53 ; metabolism

OBJECTIVETo study the safety and efficacy of three-dimensional conformal radiotherapy in combination with temozolomide in treatment of patients with diffuse brainstem glioma.

METHODSTwelve patients with MRI-confirmed diffuse brainstem glioma received 54 Gy three-dimensional conformal radiotherapy for 6 weeks with 1.8 Gy per fraction, 5 times per week. All of the patients were given daily oral temozolomide 75 mg/m(2) during radiotherapy. Four weeks after radiotherapy, all of the patients received 6 cycles of temozolomide, each cycle lasted 5 days with 28 days interval between each two cycles. 150 mg/m(2) of temozolomide was given for the first cycle for five days, followed by 200 mg/m(2) of the drug for the rest of the cycles if no significant drug-related toxicities were observed. Magnetic resonance imaging and laboratory tests were performed to evaluate the efficacy and adverse reactions.

RESULTSIn the 12 patients, CR was 1 case (8.3%), PR 6 cases (50.0%), SD 2 cases (16.7%), and PD 3 cases (25.0%). The overall clinical benefit rate was 75.0%. Progression-free survival rate was 75.0% (9/12) at 6 months and 50.0% (6/12) at 1 year. The one-year overall survival rate was 75.0%. There were no severe temozolomide-related toxicities.

CONCLUSIONSConcurrent temozolomide with three-dimensional conformal radiotherapy and followed by 6 cycles of temozolomide chemotherapy for diffuse brainstem gliomas have a better clinical efficacy, good tolerance and with no severe toxicities.

Adolescent ; Adult ; Antineoplastic Agents, Alkylating ; adverse effects ; therapeutic use ; Brain Injuries ; etiology ; Brain Stem Neoplasms ; pathology ; therapy ; Chemoradiotherapy ; Child ; Dacarbazine ; adverse effects ; analogs & derivatives ; therapeutic use ; Disease-Free Survival ; Female ; Glioma ; pathology ; therapy ; Humans ; Leukopenia ; chemically induced ; Male ; Middle Aged ; Radiation Injuries ; etiology ; Radiotherapy, Conformal ; adverse effects ; methods ; Remission Induction ; Survival Rate ; Young Adult