Intratumoral homogeneity of MGMT promoter hypermethylation as demonstrated in serial stereotactic specimens from anaplastic astrocytomas and glioblastomas.

Hypermethylation of the DNA repair gene O(6)-methyl-guanine DNA methyltransferase (MGMT) has been linked to prolonged survival in glioblastoma patients treated with alkylating agents. It was aimed to analyze prospectively whether the MGMT status of malignant gliomas could be determined from small-sized stereotactic biopsies (maximum volume: 1 mm(3)). Special attention was directed towards the intratumoral distribution of the MGMT promoter methylation, the MGMT protein expression and potential correlations between both.

Tourniquet use in childhood: a harmless procedure?

Tourniquet ischemia is widely used in limb surgery in every age group. In adults, tourniquet-related deep vein thrombosis and pulmonary embolism are recognized complications of tourniquet use. In healthy children, tourniquet-associated alterations of blood clotting physiology are assumed to have no clinical impact.

Photodynamic therapy of prostate cancer by means of 5-aminolevulinic acid-induced protoporphyrin IX - in vivo experiments on the dunning rat tumor model.

Objective: In order to expand the use of photodynamic therapy (PDT) in the treatment of prostate carcinoma (PCA), the aim of this study was to evaluate PDT by means of 5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PPIX) in an in vivo tumor model.

Methods: The model used was the Dunning R3327 tumor. First of all, the pharmacokinetics and the localization of PPIX were obtained using fluorescence measurement techniques.

Endothelial cells but not epithelial cells or cardiomyocytes are partially replaced by donor cells after allogeneic bone marrow and stem cell transplantation.

Recent studies have convincingly demonstrated that adult bone marrow contains cells capable of differentiating into a variety of cell types. To investigate whether such bone marrow-derived cells participate on self-renewal and proliferation of nonhematopoietic tissues, we studied tissue obtained by autopsy from female recipients after sex-mismatched allogeneic bone marrow and stem cell transplantation for the presence of donor-derived cells. Epithelial, endothelial, and smooth muscle cells and hematopoietic cells were characterized by double-staining immunohistochemistry with a panel of antibodies and nonisotopic in situ hybridization with a Y-chromosome-specific probe.

Novel tumor antigens identified by autologous antibody screening of childhood medulloblastoma cDNA libraries.

Medulloblastoma is an embryonal childhood malignancy with poor prognosis. By screening 4 medulloblastoma cDNA expression libraries (SEREX) with autologous sera, 15 different antigens were identified. These antigens were encoded by 3 novel genes, genes of unknown function (KIAA0445, KIAA1853, KIAA0665, FLJ13942, HSPC213), a proto-oncogene (rab18), candidate tumor suppressor genes (BAP1, PRDM13) and genes encoding a motor protein (kinesin-2), a histone (H2A1.

Photoirradiation therapy of experimental malignant glioma with 5-aminolevulinic acid.

Object: Accumulation of protoporphyrin IX (PPIX) in malignant gliomas is induced by 5-aminolevulinic acid (5-ALA). Because PPIX is a potent photosensitizer, the authors sought to discover whether its accumulation might be exploited for use in photoirradiation therapy of experimental brain tumors, without injuring normal or edematous brain.

Methods: Thirty rats underwent craniotomy and were randomized to the following groups: 1) photoirradiation of cortex (200 J/cm2, 635-nm argon-dye laser); 2) photoirradiation of cortex (200 J/cm2) 6 hours after intravenous administration of 5-ALA (100 mg/kg body weight); 3) cortical cold injury for edema induction; 4) cortical cold injury with simultaneous administration of 5-ALA (100 mg/kg body weight) and photoirradiation of cortex (200 J/cm2) 6 hours later; or 5) irradiation of cortex (200 J/cm2) 6 hours after intravenous administration of Photofrin II (5 mg/kg body weight).