1/7. Detailed genome-wide screening for inter- and intrachromosomal abnormalities by sequential G-banding and RxFISH color banding of the same metaphase cells.While the now-classic chromosome banding methods, such as G-banding, remain the techniques of choice for the initial screening for karyotypic abnormalities, sometimes chromosomal rearrangements involve segments too small or too similarly banded to be detected or described adequately by these techniques. The necessity to use a genome-wide, fluorescence in situ hybridization (FISH)-based screening technique as a complement to G-banding is especially obvious in cases where the information obtained by the latter analysis does not provide an adequate guide to the choice of probes for chromosome-specific FISH. Furthermore, the same metaphase cells should ideally be used for both G-banding and FISH analysis to overcome the scarcity of metaphases observed in many cases and to ensure the correct interpretation of chromosomal aberrations in cytogenetically unstable neoplasms with massive cell-to-cell karyotypic variability. We describe a protocol which enables cross-species color banding (RxFISH), a new FISH-based screening technique that simultaneously imparts specific color banding patterns on all chromosomes, of preparations that have been G-banded and mounted for up to several years, as well as a procedure allowing chromosome-specific painting of the same metaphase cells to resolve whatever doubts persist after the preceding G-banding and RxFISH analyses. This approach makes possible a detailed, genome-wide screening for inter- and intrachromosomal abnormalities including archival cases whose karyotypic rearrangements had been incompletely identified by G-banding.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/7. Neoplastic disease and deletion 22q11.2: a multicentric study and report of two cases.Deletion 22q11.2 is a chromosomal abnormality detected in young patients with clinical manifestations of the DiGeorge/velocardiofacial syndrome. Conotruncal heart defects are also associated with del22q11.2. An association of these cardiac malformations with neoplasias has been observed. Our series includes two cases of malignancies, a hepatoblastoma and a renal-cell carcinoma, arising in children with complex cardiac malformations. The aim of the study was to determine if the deletion at 22q11.2 was present and could be responsible for both pathological processes. Del22q11.2 was identified in both cases. comparative genomic hybridization revealed terminal gains on chromosomes 1q and Xq and terminal loss on 1p in the hepatoblastoma, and gains in 1p, 12q, 16p, 20q, 22q, and whole chromosome 19 and loss of Xq in the renal-cell carcinoma. Our results confirm a common genetic basis for cardiac malformations, and del22q11.2 presents a risk factor for the development of pediatric tumours.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/7. Use of fluorescent in situ hybridization for marker chromosome identification in congenital and neoplastic disorders.Identifying marker chromosomes of unknown origin in the clinical cytogenetics laboratory has been a problem historically, despite advances in specialized staining techniques. Determination of the origin of these marker chromosomes in patients with congenital or malignant neoplastic disorders is essential for more complete diagnosis, counseling, and treatment. The authors describe the use of fluorescent in situ hybridization with chromosome-specific alpha-satellite dna probes to identify the origin of marker chromosomes in two patients with congenital disorders and three patients with malignant neoplastic disorders. The impact of firm identification of the marker chromosome for the diagnosis of these patients is discussed. The authors also discuss the feasibility of using this technique routinely in the clinical cytogenetics laboratory.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |
4/7. female genital tumors associated with human papillomavirus infection, and the concept of genital neoplasm-papilloma syndrome (GENPS).With the recent development of new analytic methods, notably the DNA hybridization technique, many benign and malignant gynecologic tumors including carcinoma in situ, verrucous carcinoma and some invasive carcinomas of the vulva, the vagina and the cervix are found to be associated with human papillomavirus infection. Benign warts and multiple neoplasms frequently appear synchronously or metachronously in a single patient, and thus present as the genital neoplasm-papilloma syndrome (GENPS). Various methods of human papillomavirus identification and a spectrum of benign and malignant female genital tumors proven to contain human papillomavirus are reviewed and summarized.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/7. Analysis of phenotype and genotype of individual cells in neoplasms.The authors describe a combination technique enabling detection of in situ hybridization (ISH) signals from chromosome-specific probes in interphase or mitotic cells that still retain the alkaline phosphatase antialkaline phosphatase (APAAP) or sudan black B (SBB) staining reactions (simultaneous detection) or have been first classified morphologically and then by APAAP or SBB. The technique can be used on cell suspensions, in situ cultures and tissue sections. Examples from leukemias (chronic lymphocytic, myeloid, and acute myeloid leukemia) and solid tumors (chondromyxoid fibroma and glioblastoma) illustrate the potential of the technique in investigation of cancer tissue heterogeneity. In leukemias, it can be used to study cell lineage involvement, stem cells, and minimal residual disease, as well as to monitor therapy. In solid tumors, it can be used to identify neoplastic areas of tissue and to track the site of origin of neoplastic cells. Finally, it can be used to study the significance of chromosome abnormalities in carcinogenesis.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/7. Retrospective study on the influence of human parvovirus B19 infection among children with malignant diseases.Human parvovirus B19 (B19) is a known cause of erythema infectiosum (fifth disease) and aplastic crisis in patients with hemolytic anemias. When patients with malignant diseases are infected by B19 during chemotherapy, erythroid suppression of bone marrow sometimes occurs. We performed a retrospective investigation of B19 infection among 95 children with malignant diseases in our hospital during the past 14 years. By the method of dot blot hybridization, 9 of 95 patients were found to be positive for B19 DNA during chemotherapy. All 9 patients had reticulocytopenia at the time B19 DNA was detected in their serum samples. neutropenia and thrombocytopenia were not found. Seven of them had only transient reticulocytopenia. serum samples from 2 other patients were positive for B19 DNA for a longer time. They suffered from persistent anemia for about 2 and 13 month, respectively. The years when B19 DNA was detected from the 9 patients corresponded to the prevalence of erythema infectiosum in japan.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/7. Familial supernumerary chromosome and malignancy.No familial marker chromosome associated with a malignancy has been reported to date. We used fluorescence in situ hybridization (FISH) to characterize a supernumerary marker chromosome 15 ascertained during prenatal diagnosis. This supernumerary chromosome 15 was found to span three generations of a family. Three family members carrying the supernumerary chromosome 15 have also had malignancies, namely, a cystic glioma, leukemia, and thyroid cancer.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |