Search results for "Cytogenetic"
showing 10 items of 159 documents
A new pericentric inv(8) in acute nonlymphocytic leukemia.
1993
Abstract Chromosome studies were carried out on unstimulated bone marrow cells from a patient with a diagnosis of acute nonlymphocytic leukemia (FAB M6 ANLL). Cytogenetic analysis revealed a mosaic chromosome pattern 46,XX46,XX,inv(8)(p21q24). This pericentric inversion has not been previously described in ANLL. Because, fragile sites, zinc finger gene loci, and the MYC protooncogene have been localized to band 8q24, a putative role for these sites and genes could be considered.
Complex rearrangement of chromosomes 6 and 11 as the sole anomaly in atypical teratoid/rhabdoid tumors of the central nervous system.
2000
Atypical teratoid/rhabdoid tumor of the central nervous system is a rare childhood tumor with a distinct histologic appearance and an aggressive clinical course. Few tumors have been analyzed cytogenetically. The only consistent chromosomal abnormality identified in some of these tumors has been monosomy or deletions of chromosome 22; in others, a normal chromosome 22 was present. The authors report an atypical teratoid/rhabdoid neoplasm of the central nervous system with a novel complex rearrangement affecting chromosomes 6 and 11 as the sole anomaly. The involvement of region 11p15 could be important in the pathogenesis of this entity.
Low frequency of HLA haplotype loss associated with loss of heterozygocity in chromosome region 6p21 in clear renal cell carcinomas.
2004
HLA class I loss or downregulation is a widespread mechanism used by tumor cells to avoid tumor recognition by cytotoxic T lymphocytes favoring tumor immune escape. Multiple molecular mechanisms are responsible for these altered HLA class I tumor phenotypes. It has been described in different epithelial tumors that loss of heterozygosity (LOH) at chromosome region 6p21.3 is a frequent mechanism that leads to HLA haplotype loss, ranging between 40 and 50%, depending on the tumor entity analyzed. Here we have tested the frequency of LOH at 6p21 chromosome region in Renal Cell Carcinomas (RCC) of the clear cell and chromophobe subtype. A low frequency of HLA haplotype loss (6.6%) was found in …
Cytogenetic analysis of epithelial renal-cell tumors: Relationship with a new histopathological classification
1993
Renal-cell carcinomas (RCC) are clinically, histologically and cytogenetically very heterogeneous. The present histological WHO classification shows no clear correlation between histologic subtypes and specific chromosomal abnormalities. In 1986, a new classification was proposed by Thoenes and Storkel based on the cell type from which the tumor arises. They distinguish S cell types: clear-cell, chromophilic, chromophobic, ductus Bellini and oncocytic. Results of 105 primary tumors show that, in this new classification, there is a correlation between different subtypes of renal-cell tumor and specific chromosomal abnormalities at a microscopic and/or molecular level. The clear-cell compact …
Cytogenetic findings in malignant mixed mesodermal tumors of the uterus.
1997
Abstract Cytogenetic analyses of four malignant mixed mesodermal tumors (MMMT) of the uterus are reported, of which one was of the homologous type and three of the heterologous type. Karyotypic analyses were obtained in two cases from original tumors and in two cases from tumors xenotransplanted into nude mice. The karyotype of the homologous MMMT was normal in three different passages of a nude mice xenograft line established from the primary tumor. The heterologous tumors showed normal karyotype in one case and hyperdiploid and near triploid range with extensive numerical and structural rearrangements in two cases. Deletion of chromosome 1 at p32, and deletion of chromosome 11 at q13 were…
Molecular cytogenetics of childhood hematological malignancies
1998
Cytogenetic and molecular analyses are essential for the classification of childhood hematologic malignancies. Nearly all children with leukemia should have an adequate cytogenetic analysis which in 80-90% is expected to show clonal chromosomal abnormalities. Moreover, with the availability of appropriate gene probes and sophisticated molecular techniques, genetic rearrangements become detectable in the majority of leukemia patients. Genetic abnormalities often associate with particular clinical-biological characteristics of the disease. In ALL, for example, genetic alterations together with distinct immunologic and clinical features, define various subgroups. In AML, unique cytogenetic rea…
Involvement of the chromosomal region 11q13 in renal oncocytoma: case report and literature review.
1997
Renal oncocytomas comprise a cytogenetically heterogeneous group of tumors consisting potentially of cytogenetic distinguishable subgroups. Review of the literature revealed loss of chromosome 1 and Y as a possible anomaly for at least one subset of oncocytomas. The frequent finding of rearrangements involving chromosome 11 band q13 characterizes another subset of oncocytomas. We report the cytogenetic and pathological features of a renal oncocytoma diagnosed in a 72-year-old woman and found a t(9;11)(p23;q13) as a consistent abnormality. This supports the idea that translocations involving 11q13 define a further subset of oncocytoma. (C) Elsevier Science Inc., 1997.
Metabolic aggressiveness in benign meningiomas with chromosomal instabilities.
2010
Abstract Meningiomas are often considered benign tumors curable by surgery, but most recurrent meningiomas correspond to histologic benign tumors. Because alterations in chromosome 14 among others have suggested clinical aggressiveness and recurrence, determining both the molecular phenotype and the genetic profile may help distinguish tumors with aggressive metabolism. The aim of this study was to achieve higher specificity in the detection of meningioma subgroups by measuring chromosomal instabilities by fluorescence in situ hybridization and cytogenetics and metabolic phenotypes by high-resolution magic angle spinning spectroscopy. We studied 46 meningioma biopsies with these methodologi…
GIST: Particular aspects related to cell cultures, xenografts, and cytogenetics
2006
In less than half a decade, gastrointestinal stromal tumors (GIST) have emerged from historical anonymity to become a model of kinase-targeted therapies. Approximately 80% to 85% of GISTs harbor activating mutations of the KIT or PDGFRA tyrosine kinase genes, and such mutations have predictive and prognostic value. In this regard, the in vitro and in vivo models have provided valuable tools for understanding the molecular pathology of this interesting neoplasm. This review charts particular aspects in the field of cell cultures and tumor xenografts in nude mice in GIST and their implication in the establishment of appropriate models for discovering and testing therapy. The cytogenetic featu…
Preliminary data on cytogenetics and cytotaxonomy of Cercopithecus albogoularis labiatus (Samango monkey)
2010
Preliminary data on cytogenetics and cytotaxonomy of Cercopithecus albogoularis labiatus (Samango monkey) L. Sineo1, M. Roccella1, B. Picone1, R. Stanyon2, F. Genin3 and J. Masters 3 1Dipartimento di Biologia animale, Università di Palermo, Italia; 2Dipartimento di Biologia evoluzionistica, Università di Firenze, Italia; 3Department of Zoology and Entomology, University of Fort Hare, Alice, South Africa The systematic status and phylogenetic relationships of the C. mitis “species group” are contentious. The species group effectively includes very different species (C. nictitans, C. mitis, and C. albogularis) with wide, reciprocally remote distribution in Africa, and high regional variabilit…