Lymphocyte adhesion molecule ligands and extracellular matrix proteins in gliomas and normal brain: expression of VCAM-1 in gliomas

To identify antigenic differences between gliomas and normal brain, we have immunohistochemically studied the expression of lymphocyte adhesion molecules (ICAM-1, ICAM-2, ICAM-3, VCAM-1, E-selectin and CD58), epidermal growth factor receptor (EGFR) and extracellular matrix proteins (collagen IV, fibronectin, laminin, merosin, tenascin and vitronectin) in these tissues. Gliomas expressed high levels of ICAM-1, CD58 (LFA-3), EGFR, tenascin and vitronectin, whereas only very low levels were detected in normal brain. VCAM-1 expression was detected in 15 out of 25 gliomas but not in normal brain. The presence of VCAM-1 in gliomas was verified by immunoblotting and RNase protection assay, and in glioma cell lines by Northern blotting. Expression of VCAM-1 in gliomas may partially explain lymphocytic infiltration, and anti-VCAM-1 antibodies may be of potential in antibody mixtures for targeted therapy of gliomas. Received: 9 December 1996 / Revised, accepted: 20 February 1997     

Divergent expression changes of telomerase and E6/E7 mRNA, following integration of human papillomavirus type 33 in cultured epithelial cells

Expression of the viral oncogenes E6 and E7, and telomerase, was investigated, using a cell line from a mild dysplastic vaginal lesion containing human papillomavirus (HPV) type 33. During passaging of the cells, there was a change towards a cancer phenotype, and a shift from episomal to integrated HPV. Levels of hTERT (catalytic subunit of telomerase) mRNA, and telomerase activity in cells carrying episomal virus seemed constant during passaging. During passaging of cells containing integrated HPV, however, the levels of oncogene mRNA decreased, while hTERT mRNA and telomerase activity increased sharply. Thus, in those cells there is no direct correlation between changes of oncogene and telomerase expression. Conceivably, viral oncogene expression might trigger telomerase up-regulation in an early subpopulation of cells, which during subsequent passaging could be selected for.     

DAP12/TREM2 deficiency results in impaired osteoclast differentiation and osteoporotic features

Polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy (PLOSL), Nasu-Hakola disease, is a globally distributed recessively inherited disease. PLOSL is characterized by cystic bone lesions, osteoporotic features, and loss of white matter in the brain leading to spontaneous bone fractures and profound presenile dementia. We have earlier characterized the molecular genetic background of PLOSL by identifying mutations in two genes, DAP12 and TREM2. DAP12 is a transmembrane adaptor protein that associates with the cell surface receptor TREM2. The DAP12-TREM2 complex is involved in the maturation of dendritic cells. To test a hypothesis that osteoclasts would be the cell type responsible for the bone pathogenesis in PLOSL, we analyzed the differentiation of peripheral blood mononuclear cells isolated from DAP12- and TREM2-deficient PLOSL patients into osteoclasts. Here we show that loss of function mutations in DAP12 and TREM2 result in an inefficient and delayed differentiation of osteoclasts with a remarkably reduced bone resorption capability in vitro. These results indicate an important role for DAP12-TREM2 signaling complex in the differentiation and function of osteoclasts.     

How to make large self-organizing maps for nonvectorial data.

The self-organizing map (SOM) represents an open set of input samples by a topologically organized, finite set of models. In this paper, a new version of the SOM is used for the clustering, organization, and visualization of a large database of symbol sequences (viz. protein sequences). This method combines two principles: the batch computing version of the SOM, and computation of the generalized median of symbol strings.     

Radiologic bone changes of polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy

More than 50 cases of polycystic lipomembranous osteodysplasia (PLO) with sclerosing leukoencephalopathy (SL) have been described in Finland, Sweden Japan, and in the USA. Radiographic bone changes, including symmetrical cystic lesions in the small bones of the extremities and trabecular loss in the distal ends of the long tubular bones, represent primary abnormalities in the diagnosis of the disease. Neuropsychiatric symptoms, frontal syndrome, and pyramidal signs make the patients dangerous to themselves. They are often involved in traffic accidents and are prone to multiple spontaneous or almost spontaneous fractures. PLO usually starts with slight bone pain around the age of 20 years. Progress is very slow during the next ten years, but faster after the age of 40 years. The patients usually die before the age of 50 years having total dementia and epileptiform convulsions.     

Single copy heterozygote integration of HPV 33 in chromosomal band 5p14 is found in an epithelial cell clone with selective growth advantage

Infection with human papillomavirus (HPV) of specific high-risk type triggers a series of events in target cells, which will eventually lead to development of genital neoplasia. The integration of high-risk HPV DNA into the cell genome has been regarded as a crucial event in tumor progression. With respect to different HPV types, the knowledge of HPV integrated loci is still limited. We have now determined the genomic variation and chromosomal location of HPV 33 DNA in the cell line UT-DEC-1, established from a vaginal mild dysplasia lesion. The viral sequence of the cell line was determined, and a variant of the prototype HPV 33 strain was identified, showing nucleotide substitutions resulting in amino acid changes in the E2, L2 and E4 open reading frames. In late passage UT-DEC-1 cells, a deletion of more than half of the 3' part of E1 and major parts of the E2 and E4 genes provided evidence for integration. The flanking sequences of the integration site were completely homologous to published sequences from chromosomal band 5p14, and remained unchanged in all subclones established from late passage cells. There were no chromosomal deletions or gross rearrangements at the integration site, and only a single heterozygotic copy of HPV 33 was detected. The karyotype of late passage cells showed only minor changes compared with early passage cells. During passaging of the cell line, there were progressive changes towards a malignant phenotype, and in parallel to this, the cells carrying episomal HPV 33 of the early passages was completely superseded by cells containing the integrated virus. Thus, our results show that this single copy heterozygote integration of HPV 33 into chromosome band 5p14 appears to be associated with emergence of cells escaping senescence, and with growth advantage compared with cells carrying episomal virus.     

Angio-seal in antegrade endovascular interventions: technical success and complications in a 55-patient series.

PURPOSE: To assess the technical success and complications of Angio-Seal vascular closure device in antegrade common femoral artery (CFA) punctures. METHODS: Over a 14-month period, 55 patients (37 men; age range 37-94 years) underwent antegrade CFA Angio-Seal placement at a single center; the clinical data and angiograms were reviewed retrospectively. A total of 56 antegrade CFA punctures were made for hemostasis; 6-F Angio-Seal devices (40 model STS and 12 model VIP) were deployed in 52 CFAs, and 8-F Angio-Seal devices were deployed in 4. RESULTS: The technical success rate was 98.2% (55/56). Two (3.6%) patients developed small, non-expanding hematomas (<5 cm) during deployment of the device. There was 1 episode of device/operator failure, presumably due to extravascular deployment within soft tissue. None of the patients developed pseudoaneurysm, arterial injury, or large hematomas requiring transfusion. Small calcified plaques at the puncture site did not influence the outcome. CONCLUSION: This series suggests that Angio-Seal may be a safe and effective device for hemostasis in antegrade CFA punctures. Further randomized trials testing its risk-benefit balance in comparison to standard manual compression are warranted.     

Correlations between total protein,lysozyme, immunoglobulins,amylase, and albumin in stimulated whole saliva during daytime

The correlations between salivary proteins and the daytime variations are not known. The present study investigated the within-subject variation of correlations and concentrations between lysozyme, IgA, IgG, IgM, albumin, amylase, and total protein in stimulated whole saliva of healthy adults in the course of a 12-h period. After several practise sessions, unstimulated and stimulated whole saliva samples were collected five times daily (at 8 a.m., 11 a.m., 2 p.m., 5 p.m., and 8 p.m.) from 30 healthy university students. Flow rate and total protein concentration were used as covariates, and gender as a between-subject factor in the MANOVA analysis. After this adjustment, there was significant within-subject variation in salivary IgA (P &lt; 0.001), albumin (P &lt; 0.01), amylase (P &lt; 0.05), and total protein (P &lt; 0.001) concentrations. Total protein correlated significantly with amylase albumin and IgA through different samplings. In addition, IgG correlated with albumin and lysozyme in the course of 12 h. On the whole, the correlations between variables remained stable during repeated samplings. In addition, rankings of subjects for the variables tended to be maintained across different samplings (P &lt; 0.001). However, the observed within-subject variations in salivary IgA, albumin, amylase, and total protein concentrations suggest that these proteins are subject to short-term variation.     

The C9ORF72 expansion does not affect the phenotype in Nasu-Hakola disease with the DAP12 mutation

Nasu-Hakola disease (NHD) is a rare autosomal recessive disease that is characterized by cyst-like bone lesions and pathologic fractures combined with an early-onset frontal type of dementia. Mutations in DNAX-activation protein 12 (DAP12) and triggering receptor expressed on myeloid cells 2 (TREM2) are the known genetic causes of NHD. However, the role of both these genes in the neurodegenerative process is still partly unclear, and the input of other modifying factors has been postulated. Frontotemporal lobar degeneration (FTLD) is a neuropathologically and genetically heterogeneous neurodegenerative disease. A hexanucleotide repeat expansion in the chromosome 9–associated open reading frame 72 (C9ORF72) gene is the most common cause of familial FTLD in Finland. Here, we describe a family with 3 siblings with a clinical diagnosis of NHD. All patients had an equivalent age of onset of the behavioral/cognitive symptoms, and brain imaging revealed a similar pattern of brain atrophy and calcification in putamen and caudate nucleus. Case II-3 had the most severe phenotype with epilepsy and a rapid cognitive decline. Genetic analyses were performed in 2 patients (cases II-2 and II-3), and both had a homozygous DAP12 deletion. Because the role of DAP12 and TREM2 in neurodegeneration in NHD is partly unclear, our aim was to evaluate the role of other genetic variations as modifiers. The C9ORF72 expansion was found in case II-2. Exome sequencing did not reveal any other mutations that could be involved in FTLD. Case II-3 had a novel predictably deleterious mutation in the progressive myoclonic epilepsy type 2 (EPM2), which may have influenced his epilepsy as the EPM2 has been implicated in Lafora progressive myoclonic epilepsy. We conclude that the C9ORF72 expansion is probably an incidental finding because it did not have any apparent influence on the phenotype. Exome sequencing identified several rare missense variants and indels. Additional analyses in other NHD patients will be needed to elucidate their clinical relevance.