Identification of BRAF p. V600E-Mutant and Wild-Type by MR Imaging in Pleomorphic Xanthoastrocytoma and Anaplastic Pleomorphic Xanthoastrocytoma

Abstract Radiation-induced gliomas (RIGs) are the most common secondary solid tumours with very unfavourable prognosis. We aimed to describe different clinical and molecular biological characteristic of RIGs from primary gliomas. We reviewed clinical data of ten patients with RIGs. In patients with available samples, we used the whole genome methylation array and performed targeted sequencing for specific mutations. Between 2000–2018, we diagnosed RIG in 10 patients (M/F 2/8) aged 5–12 years at primary diagnosis of different solid tumours and acute leukaemia. These patients developed RIG with a median 9.5 years (ranging 3–31) after primary diagnosis. Eight patients died within 1 year after diagnosis of RIG and 2 patients are still alive more than 4 years from this diagnosis. According to Heidelberg DNA methylation-based classification, most RIGs belong to the IDH-wild type glioblastoma subclass midline which biologically corresponds to diffuse midline glioma (DMG). However, compared to primary DMGs they do not carry the characteristic H3K27M mutation. One patient developed anaplastic ganglioglioma with BRAF-V600E mutation and methylation profile identical to pleomorphic xanthoastrocytoma (alive for 4 years after diagnosis of RIG). In half of the patients from the group DMGs IDH wild type, examined by methylation array, PDGFRA amplification was found. Our data shows that most RIGs are midline IDH-wild type glioblastomas with poor prognosis that are biologically different from primary DMGs. PDGFRA amplifications are potentially targetable by kinase inhibitors in order to order to prognosis of these patients.

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MR Imaging Features of Anaplastic Pleomorphic Xanthoastrocytoma Mimicking High-Grade Astrocytoma

American Journal of Neuroradiology ◽

10.3174/ajnr.a5701 ◽

2018 ◽

Cited By ~ 1

Author(s):

D. She ◽

J. Liu ◽

Z. Xing ◽

Y. Zhang ◽

D. Cao ◽

...

Keyword(s):

Mr Imaging ◽

Pleomorphic Xanthoastrocytoma ◽

Imaging Features ◽

High Grade ◽

High Grade Astrocytoma

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NIMG-10ASSESSMENT OF BEVACIZUMAB RESISTANCE RELATED WITH EXPRESSION OF BRANCHED-CHAIN AMINO ACID TRANSAMINASE-1 IN ISOCITRATE DEHYDROGENASE-1 WILD-TYPE GLIOBLASTOMA: APPLICATION OF DSC MR IMAGING

Neuro-Oncology ◽

10.1093/neuonc/nov225.10 ◽

2015 ◽

Vol 17 (suppl 5) ◽

pp. v155.2-v155

Author(s):

Hye Rim Cho ◽

Seung Hong Choi ◽

Chul-Kee Park ◽

Sung-Hye Park ◽

Hyeonjin Kim

Keyword(s):

Amino Acid ◽

Mr Imaging ◽

Isocitrate Dehydrogenase ◽

Wild Type ◽

Isocitrate Dehydrogenase 1 ◽

Branched Chain Amino Acid ◽

Branched Chain

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Ultrastructure of Melanin Formation in Curvularia sp., Alternaria sp., and Drechslera Sorokiniana

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100079449 ◽

1977 ◽

Vol 35 ◽

pp. 398-399

Author(s):

M. H. Wheeler ◽

W. J. Tolmsoff ◽

A. A. Bell

Keyword(s):

Potassium Phosphate ◽

Thielaviopsis Basicola ◽

Wild Type ◽

Potassium Phosphate Buffer ◽

Transmission Microscopy ◽

Electron Transmission ◽

Melanin Formation ◽

Before And After ◽

Alternaria Sp ◽

Electron Transmission Microscopy

(+)-Scytalone [3,4-dihydro-3,6,8-trihydroxy-l-(2Hj-naphthalenone] and 1,8-di- hydroxynaphthalene (DHN) have been proposed as intermediates of melanin synthesis in the fungi Verticillium dahliae (1, 2, 3, 4) and Thielaviopsis basicola (4, 5). Scytalone is enzymatically dehydrated by V. dahliae to 1,3,8-trihydroxynaphthalene which is then reduced to (-)-vermelone [(-)-3,4- dihydro-3,8-dihydroxy-1(2H)-naphthalenone]. Vermelone is subsequently dehydrated to DHN which is enzymatically polymerized to melanin.Melanin formation in Curvularia sp., Alternaria sp., and Drechslera soro- kiniana was examined by light and electron-transmission microscopy. Wild-type isolates of each fungus were compared with albino mutants before and after treatment with 1 mM scytalone or 0.1 mM DHN in 50 mM potassium phosphate buffer, pH 7.0. Both chemicals were converted to dark pigments in the walls of hyphae and conidia of the albino mutants. The darkened cells were similar in appearance to corresponding cells of the wild types under the light microscope.

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Ultrastructure and Morphology of the Neurospora Crassa Cell Wall Mutants, Slime And Slime X, Using Tem and Sem

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100090257 ◽

1976 ◽

Vol 34 ◽

pp. 54-55

Author(s):

Karen S. Howard ◽

H. D. Braymer ◽

M. D. Socolofsky ◽

S. A. Milligan

Keyword(s):

Cell Wall ◽

Neurospora Crassa ◽

Wild Type ◽

Morphological Comparison ◽

Small Areas ◽

Solid Media ◽

Thin Sectioning ◽

X Cells ◽

Mutant Cells ◽

Isolated Cell

The recently isolated cell wall mutant slime X of Neurospora crassa was prepared for ultrastructural and morphological comparison with the cell wall mutant slime. The purpose of this article is to discuss the methods of preparation for TEM and SEM observations, as well as to make a preliminary comparison of the two mutants.TEM: Cells of the slime mutant were prepared for thin sectioning by the method of Bigger, et al. Slime X cells were prepared in the same manner with the following two exceptions: the cells were embedded in 3% agar prior to fixation and the buffered solutions contained 5% sucrose throughout the procedure.SEM: Two methods were used to prepare mutant and wild type Neurospora for the SEM. First, single colonies of mutant cells and small areas of wild type hyphae were cut from solid media and fixed with OSO4 vapors similar to the procedure used by Harris, et al. with one alteration. The cell-containing agar blocks were dehydrated by immersion in 2,2-dimethoxypropane (DMP).

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Freeze-substituted fungal cells of Nectria haematococca: A comparison of the macroconidial walls of the adhesion-competent wild type with an adhesion-reduced mutant

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100160996 ◽

1990 ◽

Vol 48 (3) ◽

pp. 688-689

Author(s):

Thecan Caesar-Ton That ◽

Lynn Epstein

Keyword(s):

Freeze Substitution ◽

Uranyl Acetate ◽

Wild Type ◽

Nectria Haematococca ◽

Fruit Extract ◽

Dialysis Tubing ◽

Tube Emergence ◽

Contrast Microscopy ◽

In The Wild ◽

Freeze Damage

Nectria haematococca mating population I (anamorph, Fusarium solani) macroconidia attach to its host (squash) and non-host surfaces prior to germ tube emergence. The macroconidia become adhesive after a brief period of protein synthesis. Recently, Hickman et al. (1989) isolated N. haematococca adhesion-reduced mutants. Using freeze substitution, we compared the development of the macroconidial wall in the wild type in comparison to one of the mutants, LEI.Macroconidia were harvested at 1C, washed by centrifugation, resuspended in a dilute zucchini fruit extract and incubated from 0 - 5 h. During the incubation period, wild type macroconidia attached to uncoated dialysis tubing. Mutant macroconidia did not attach and were collected on poly-L-lysine coated dialysis tubing just prior to freezing. Conidia on the tubing were frozen in liquid propane at 191 - 193C, substituted in acetone with 2% OsO4 and 0.05% uranyl acetate, washed with acetone, and flat-embedded in Epon-Araldite. Using phase contrast microscopy at 1000X, cells without freeze damage were selected, remounted, sectioned and post-stained sequentially with 1% Ba(MnO4)2 2% uranyl acetate and Reynold’s lead citrate. At least 30 cells/treatment were examined.

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