1/7. A novel Epstein-Barr virus-like virus, HV(MNE), in a macaca nemestrina with mycosis fungoides.Epstein-Barr virus (EBV) infection of humans has been associated with the development of lymphoid malignancies mainly of B-cell lineage, although occasionally T-cell lymphomas have been reported. We describe here the characterization of a novel EBV-like virus (HV(MNE)) isolated from a simian T-cell lymphotropic virus type I/II (STLV-I/II) seronegative pigtailed macaque (macaca nemestrina) with a cutaneous T-cell lymphoma. immunohistochemistry studies on the skin lesions demonstrated that the infiltrating cells were of the CD3( )/CD8( ) phenotype. Two primary transformed CD8( ) T-cell lines were obtained from cultures of peripheral blood mononuclear cells (PBMC) and skin, and, with time, both cell lines became interleukin-2-independent and acquired the constitutive activation of STAT proteins. polymerase chain reaction analysis of the dna from the cell lines and tissues from the lymphomatous animal demonstrated the presence of a 536-bp dna fragment that was 90% identical to EBV polymerase gene sequences, whereas the same dna was consistently negative for STLV-I/II sequences. Electron microscopy performed on both cell lines, after sodium butyrate treatment, showed the presence of a herpes-like virus that was designated HV(MNE) according to the existing nomenclature. in situ hybridization studies using EBV Epstein-Barr viral-encoded rna probes showed viral RNA expression in both CD8( ) T-cell lines as well as in the infiltrating CD8( ) T cells of skin-tissue biopsies. Phylogenetic analysis of a 465-bp fragment from the polymerase gene of HV(MNE) placed this virus within the lymphocryptovirus genus and demonstrated that HV(MNE) is a distinct virus, clearly related to human EBV and other EBV-like herpesviruses found in nonhuman primates.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
2/7. Cardiac involvement and molecular staging in a fatal case of mycosis fungoides.polymerase chain reaction (PCR) amplification of T-cell receptor-gamma gene rearrangement was used for molecular staging in a case of primary cutaneous T-cell lymphoma (CTCL) with fatal evolution. Although initial evaluation was negative for systemic involvement, the patient died due to heart failure. autopsy findings revealed lymphomatous myocardial infiltration, but other tissues and organs examined, including lymph nodes, liver, spleen, lung and bone marrow, appeared to be free of disease. Molecular analysis from frozen samples obtained during the initial evaluation, as well as paraffin-embedded material obtained during autopsy, revealed the presence of clonal rearranged bands in all tissues examined except the bone marrow. Subsequent hybridization of PCR products with a tumour-specific oligoprobe confirmed the PCR results, suggesting widespread dissemination of the lymphomatous process. The use of molecular analysis can add significant information about the extent of disease in patients with CTCL and may be helpful in the establishment of therapeutic options.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
3/7. Large cell transformation of sezary syndrome. A conventional and molecular cytogenetic study.Hyperdiploidy sometimes is found in mycosis fungoides-sezary syndrome, but its diagnostic significance remains undefined. We report an unusual case of sezary syndrome manifesting with leukemic large cell transformation. Conventional karyotypic analysis showed the presence of a near-tetraploid neoplastic clone. With dual-color cytometric analysis, we showed that the large Sezary cells were near-tetraploid with a dna index of 1.86, thereby demonstrating a direct relationship between cell size and ploidy. comparative genomic hybridization further showed chromosomal imbalances that were not revealed on conventional karyotyping. Our findings suggest that hyperdiploidy may be a marker of large cell transformation, so that when this karyotypic abnormality is found in mycosis fungoides-sezary syndrome, a search for such a complication is indicated.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
4/7. Epstein-Barr virus-negative Hodgkin's lymphoma after mycosis fungoides: molecular evidence for distinct clonal origin.The association of mycosis fungoides (MF) and Hodgkin's lymphoma is a relatively frequent occurrence, but the potential clonal relationship of the two neoplasms is still controversial. We report a case of a patient with a history of MF in Clinical Stage 1A who developed retroperitoneal lymphadenopathy 9 years after the initial diagnosis of MF. A bone marrow biopsy obtained at this time showed nodular involvement by a mixed cellular infiltrate with large, atypical cells consistent with Hodgkin and Reed-Sternberg (RS) cells. These atypical cells were positive for CD30 and CD15 and did not express B- or T-cell markers. In addition, they lacked evidence of infection by Epstein-Barr virus, both by immunohistochemical staining for latent membrane protein 1 and by in situ hybridization for EBER1/2. The background population consisted mainly of small T cells without morphological or phenotypical signs of malignancy. review of the skin biopsy obtained 9 years before showed the typical features of MF. polymerase chain reaction analysis of the T-cell receptor T-gene confirmed the presence of a clonal T-cell rearrangement in the skin specimen. The bone marrow biopsy, however, showed a polyclonal pattern both for the T-cell receptor gamma-gene, as well as for immunoglobulin heavy chain genes. Isolation of RS cells stained for CD30 was performed by laser capture microdissection. polymerase chain reaction analysis of several groups of RS cells showed a reproducible biallelic rearrangement of IgH genes, which was confirmed by cloning and sequencing of polymerase chain reaction products. To our knowledge, this is the first case in which a distinct clonal origin of MF and Hodgkin's lymphoma arising in the same patient is clearly demonstrated, based on molecular analysis of microdissected RS cells.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
5/7. A case of classical mycosis fungoides associated with human T-cell lymphotropic virus type I.A 72-year-old male patient from north-eastern iran developed the typical clinical and histopathological features of mycosis fungoides with lymphadenopathy, but without any other systemic involvement. Human T-cell lymphotropic virus (HTLV-I) antibodies were detected in the patient's serum by two different ELISAs and by Western blot using purified viral particles from MT-2 culture supernatants. Cultured peripheral blood lymphocytes were positive for labelling with anti-HTLV-I serum. Southern blot hybridization of dna extracted from a skin tumour and from an involved lymph node revealed integrated proviral dna with identical restriction patterns. This case supports a relationship between mycosis fungoides and HTLV-I and may indicate a new region of endemic HTLV-I infection.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
6/7. Clinical use of B- and T-cell gene rearrangement analysis in hematopoietic disorders.The clinical application of B- and T-cell gene rearrangement analysis is discussed relative to diagnostic problems in specific lymphoproliferative disorders. This article reviews the use of the Southern blot hybridization technique for B- and T-cell gene rearrangement detection in the analysis of various hematopoietic lesions. Several case studies are presented and analyzed.- - - - - - - - - - ranking = 1keywords = hybridization (Clic here for more details about this article) |
7/7. Acute myeloid leukemia following psoralen with ultraviolet A therapy: a fluorescence in situ hybridization study.A woman with mycosis fungoides treated by psoralen with ultraviolet A (PUVA) and electron beam therapy developed acute myeloid leukemia (AML) three years later. Karyotypic analysis of the leukemia cells revealed monosomy 7. fluorescence in situ hybridization showed that the monosomy 7 clone had accounted for about a third of the marrow cells after PUVA treatment, but replaced the entire marrow at leukemic transformation. These findings were consistent with a secondary AML evolving from an underlying myelodysplasia, supporting that puva therapy might have a mutagenic effect on hematopoietic cells. This might be related to its effect on circulating hematopoietic stem cells.- - - - - - - - - - ranking = 5keywords = hybridization (Clic here for more details about this article) |