Fibroblast activation protein (FAP) is a membrane-bound protease that is upregulated in a wide range of tumours and viewed as a marker of tumour-promoting stroma. Previously, we demonstrated ...increased FAP expression in glioblastomas and described its localisation in cancer and stromal cells. In this study, we show that FAP+ stromal cells are mostly localised in the vicinity of activated CD105+ endothelial cells and their quantity positively correlates with glioblastoma vascularisation. FAP+ mesenchymal cells derived from human glioblastomas are non-tumorigenic and mostly lack the cytogenetic aberrations characteristic of glioblastomas. Conditioned media from these cells induce angiogenic sprouting and chemotaxis of endothelial cells and promote migration and growth of glioma cells. In a chorioallantoic membrane assay, co-application of FAP+ mesenchymal cells with glioma cells was associated with enhanced abnormal angiogenesis, as evidenced by an increased number of erythrocytes in vessel-like structures and higher occurrence of haemorrhages. FAP+ mesenchymal cells express proangiogenic factors, but in comparison to normal pericytes exhibit decreased levels of antiangiogenic molecules and an increased Angiopoietin 2/1 ratio. Our results show that FAP+ mesenchymal cells promote angiogenesis and glioma cell migration and growth by paracrine communication and in this manner, they may thus contribute to glioblastoma progression.
A multifunctional surgical suite with intraoperative 3.0T MRI (ioMRI) has been operating at the Central Military Hospital, Prague since April 2008. Our experiences over the past year and the effect ...of ioMRI on the extent of pituitary adenoma resection are evaluated.
Eighty-six pituitary adenoma resections were performed in 85 patients with ioMRI in the first year of the ioMRI service. Pituitary adenoma suprasellar extension was present in 60 cases, invasion into cavernous sinus in 49 cases, and retrosellar growth in one case. The surgical goal was set before surgery: either a radical resection (49 cases) or a partial resection (37 cases).
In the group of patients where a decision for a radical resection was taken the results are as follows: ioMRI confirmed radical resection in 69.4% of the cases; ioMRI disclosed unexpected adenoma residuum and further resection led to radical resection in 22.4%.
In the group of patients where a decision for a partial resection was taken, the results are as follows: no further resection was perfomed after ioMRI in 51.3% of the cases and further resection was performed after ioMRI in 48.7% of the cases.
ioMRI seems to be a valuable tool to increase the extent of pituitary adenoma resection.
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Background: Diffuse gliomas are highly heterogenous tumors with variable biological behaviors, including high intratumor and extratumor heterogeneity, and with occurrence of recurrent lesions ...in majority of patients. During disease progression, gliomas undergo cellular and genomic evolution with newly acquired genetic properties. However, the mechanism of this complicated process associated with treatment failure is poorly understood. In this retrospective study, we performed cytogenomic analyses of primary and recurrent tumors in five patients with diffuse glioma who underwent surgical resections or biopsies of multiple recurrences. Methods: One primary and at least two recurrent freshly resected tumor tissues from each patient were analyzed using combination of cytogenomic methods. To assess specific and random copy number alterations (CNAs), I-FISH (Abbott Molecular, MetaSystems), array CGH/SNP (Agilent) and MLPA (MRC Holland) were performed. Methylation of MGMT promoter was investigated by methylation-specific MLPA (MRC Holland) and mutations of 67 genes associated with solid tumors were assessed by target NGS (Archer VariantPlex Solid Tumor, Invitae). Results: All five patients (three men and two women) experienced recurrence with newly acquired genetic or epigenetic changes. We observed a higher frequency of CNAs in recurrent gliomas than in primary tumors. Moreover, several aberrations were not detected in recurrence despite being found in earlier samples. As a primary event we proved mutation R132H of IDH1 gene. In addition, we detected methylation of the MGMT promoter, CDKN2A/B homozygous deletion, and RB1 deletion as later events that were probably associated with higher tumor grades. Besides the typical genomic changes, we detected many aberrations with unknown or unclear prognostic relevance (e.g. inframe deletion in TP53, p.Met243_Asn247del, etc.). The progression to a higher grade of glioma occurred in four patients. Conclusions: The evolutional patterns in glioma depend on clonal selection caused by CNAs, mutations, genetic drift, intratumor heterogeneity and/or the patient’s treatment. Recurrence may arise from one major tumor clone or from one or more subclones within the primary tumor through. Integrated cytogenomic analyses of genetic/epigenetic profiles of primary and all recurrent tissues can contribute to a better understanding of mechanisms responsible for these processes and to identification of new alterations related to gliomas progression and/or resistance to treatment. These biomarkers could subsequently serve as new therapeutic targets for personalized treatment.
Objective To develop and validate practical prognostic models for death at 14 days and for death or severe disability six months after traumatic brain injury.Design Multivariable logistic regression ...to select variables that were independently associated with two patient outcomes. Two models designed: “basic” model (demographic and clinical variables only) and “CT” model (basic model plus results of computed tomography). The models were subsequently developed for high and low-middle income countries separately. Setting Medical Research Council (MRC) CRASH Trial.Subjects 10 008 patients with traumatic brain injury. Models externally validated in a cohort of 8509.Results The basic model included four predictors: age, Glasgow coma scale, pupil reactivity, and the presence of major extracranial injury. The CT model also included the presence of petechial haemorrhages, obliteration of the third ventricle or basal cisterns, subarachnoid bleeding, midline shift, and non-evacuated haematoma. In the derivation sample the models showed excellent discrimination (C statistic above 0.80). The models showed good calibration graphically. The Hosmer-Lemeshow test also indicated good calibration, except for the CT model in low-middle income countries. External validation for unfavourable outcome at six months in high income countries showed that basic and CT models had good discrimination (C statistic 0.77 for both models) but poorer calibration.Conclusion Simple prognostic models can be used to obtain valid predictions of relevant outcomes in patients with traumatic brain injury.
Malignant transformation in gliomas is frequently supplemented by somatic mutations in isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2 genes. It has recently emerged that mutations in these ...genes are associated with prolonged survival and should be used as prognostic factor in management of brain cancer patients. There are several approaches in use for the detection of isocitrate dehydrogenase 1 and 2 mutations; however, these often exhibit shortcomings such as convoluted protocols with long processing time, complex (and costly) dedicated fluorescent probes, and/or demand on amounts of input DNA. Therefore, a simple and rapid method would be highly desired. Here, we present development and validation of simple and reliable isocitrate dehydrogenase 1 and 2 mutation detection assay using denaturing capillary electrophoresis. The detection sensitivity in terms of the limiting mutated allele fraction detectable estimated from a series of dilution runs was 2.9%. The method was validated by comparing to results obtained by a widely accepted detection technique, the multiplex ligation‐dependent probe amplification, on a set of 85 brain tumors. The concordance of both methods was 100%, but denaturing capillary electrophoresis assay required fivefold lower input of DNA (1 versus 5 μL of DNA at concentrations typically between 10 and 30 ng/μL).
Abstract
Background. The recognition of anaplastic foci within low-grade gliomas is of extreme importance in patients under follow-up for Grade II gliomas. We present the algorithm of MR spectroscopy ...(MRS)-guided brain biopsy and its correlation with tumour histology. Methods. Twenty-seven patients harbouring suspected Grade II/III glioma were examined on our 3T MR. 2D PRESS-CSI metabolite images of Choline/Creatine, Creatine/N-acetylaspartate and Choline/N-acetylaspartate were calculated and exported to the DICOM format. According to these maps, a stereobiopsy was performed at the point of maximum Choline/Creatine ratio prior to tumour resection. In the case of enhancing tumour, a subsequent biopsy was performed from the point of enhancement. Comparisons were made between the histology of the biopsied specimens and the resected tumours. Results. Eleven tumours were diagnosed as high-grade and sixteen as low-grade lesions. The correlation between main spectroscopic ratios (Cho/Cr and Cho/NAA) was strongly positive at the points of maximum Cho/Cr. Similar results were obtained at the points of contrast enhancement. Comparison of histological parameters of biopsy samples at the points of maximum Cho/Cr and histological examination of the completely resected tumours gives a strong correlation of tumour grade, number of mitoses and Ki-67 expression. The diagnostic accuracy of MRS-guided biopsy was 84%.
The absolute value of Cho/NAA was higher in high-grade compared to that of low-grade lesions. The value of Cho/NAA ratio of 0.9 using MRS produced a sensitivity and specificity of 78% in the differentiation between low-grade and high-grade lesions. Combining MRS with structural MR, the sensitivity increased to 86% and the specificity to 80%. Conclusions. Strong correlation was demonstrated between Cho/Cr and Ch/NAA ratios.
Strong correlation was demonstrated between histological parameters of biopsy samples taken using Cho/Cr ratio and those from total tumour examination.
Diagnostic accuracy of MRS-guided biopsy was 84%.
Sensitivity and specificity of MRS combined with structural MR reaches 86% and 80%.
Diffuse astrocytomas are characterized by their highly variable biological behavior. The possibility that tumors develop novel aberrations, with relevant biological properties, is often neglected. In ...this study, we present two cases of diffuse astrocytoma in which additional cytogenetic and epigenetic markers with potential influence on cell proliferation or differentiation were detected at relapse.
The biopsies taken from the primary and recurrent tumors of two patients were analyzed with molecular methods to detect copy number variations (CNVs), gene mutations and epigenetic changes. Both cases were characterized by the R132H mutation in the isocitrate dehydrogenase 1 (IDH1) gene. Features typical of astrocytomas, such as copy-neutral loss of heterozygosity at 17p and the deletion of the cyclin-dependent kinase inhibitor 2A (CDKN2A) gene, were also detected in both cases. These markers were present in the primary and recurrent lesions. Other aberrations, predominantly deletions or amplifications of chromosomal segments and the hypermethylation of gene promoters, were detected in the recurrent lesions.
The IDH1 mutation was the primary event, as previously reported. According to our observations, the methylation of promoters constituted later events, which may have further disrupted cell proliferation and/or differentiation, together with additional CNVs.
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