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

BACKGROUDN: Recent clinical studies have suggested that statins improve insulin resistance and glucose metabolism in the skeletal muscle of diabetic patients. To evaluate a possible component of this action, we measured free fatty acid oxidation in cultured human skeletal muscle cells (HSMC). METHODS: Seven normal controls and 7 type 2 diabetic patients underwent quadriceps muscle biopsy. The HSMCs (n=14) were treated with or without lovastatin (Lova, 20 micrometer) for 2 days, and the free fatty acid (FFA) oxidation was measured. RESULTS: Lova increased the oxidation of the long-chain FA palmitate to 271.2+/-32.7% of the control (p<0.01). Oxidation of the medium chain FA octanoate also increased after treatment of Lova (158.3+/-21.9%, p<0.05). One pathway of regulation of FFA is through AMP-activated protein kinase (AMPK) and acetyl-CoA carboxylase (ACC) phosphorylation. Following Lova treatment, AMPK phosphorylation did not show a significant change while the total protein expression of AMPK was decreased (73.6+/-6.2% of the control, p<0.01). Lova treatment significantly increased ACC phosphorylation (149.5+/-20.6% of the control, p<0.05). CONCLUSION: Lova increased FFA oxidation by increasing the ACC phosphorylation in human skeletal muscle cells. Stimulation of skeletal muscle FFA oxidation may be one mechanism by which statins act to lower intramyocellular triglyceride and improve insulin action on glucose metabolism.
Acetyl-CoA Carboxylase ; AMP-Activated Protein Kinases ; Biopsy ; Glucose ; Humans* ; Hydroxymethylglutaryl-CoA Reductase Inhibitors ; Insulin ; Insulin Resistance ; Lovastatin* ; Metabolism ; Muscle, Skeletal* ; Phosphorylation ; Quadriceps Muscle ; Triglycerides

BACKGROUNDAlcohol dependence (AD) is a complex disorder characterized by impaired control over drinking. It is determined by both genetic and environmental factors. The recent approach of genome-wide association study (GWAS) is a powerful tool for identifying complex disease-associated susceptibility alleles, however, a few GWASs have been conducted for AD, and their results are largely inconsistent. The present study aimed to screen the loci associated with alcohol-related phenotypes using GWAS technology.

METHODSA genome-wide association study with the behavior of regular alcohol drinking and alcohol consumption was performed to identify susceptibility genes associated with AD, using the Affymetrix 500K SNP array in an initial sample consisting of 904 unrelated Caucasian subjects. Then, the initial results in GWAS were replicated in three independent samples: 1972 Caucasians in 593 nuclear families, 761 unrelated Caucasian subjects, and 2955 unrelated Chinese Hans.

RESULTSSeveral genes were associated with the alcohol-related phenotypes at the genome-wide significance level, with the ankyrin repeat domain 7 gene (ANKRD7) showing the strongest statistical evidence for regular alcohol drinking and suggestive statistical evidence for alcohol consumption. In addition, certain haplotypes within the ANKRD7 and cytokine-like1 (CYTL1) genes were significantly associated with regular drinking behavior, such as one ANKRD7 block composed of the SNPs rs6466686-rs4295599-rs12531086 (P = 6.51 × 10(-8)). The association of alcohol consumption was successfully replicated with rs4295599 in ANKRD7 gene in independent Caucasian nuclear families and independent unrelated Chinese Hans, and with rs16836497 in CYTL1 gene in independent unrelated Caucasians. Meta-analyses based on both the GWAS and replication samples further supported the observed significant associations between the ANKRD7 or CYTL1 gene and alcohol consumption.

CONCLUSIONThe evidence suggests that ANKRD7 and CYTL1 genes may play an important role in the variance in AD risk.

Adult ; Aged ; Alcohol Drinking ; genetics ; Blood Proteins ; Cytokines ; Female ; Genome-Wide Association Study ; Haplotypes ; Humans ; Male ; Middle Aged ; Polymorphism, Single Nucleotide ; Proteins ; genetics ; Receptors, Cytokine ; genetics