Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The t(10;14)(q24;q11) is observed in the leukemia cells of 5-10% of cases of T-cell acute lymphoblastic leukemia (T-ALL). Recently, molecular analyses of a number of these translocations revealed simple reciprocal translocations between the T-cell receptor delta chain gene (TCRD) and a region of 10q24. We have characterized, at the molecular level, a t(10;14)(q24;q11) in a patient with T-ALL. The translocation in this case, in contrast to the previous cases, is part of a complex genetic rearrangement. In addition to a reciprocal translocation between the D delta 3 gene segment of TCRD and a region of 10q24, a local inversion occurred within TCRD, involving the D delta 2 and V delta 2 gene segments. As a consequence, the entire joining and constant regions and most of the diversity regions of TCRD are located on the derivative 14 chromosome, whereas the joining and constant regions of TCRA are positioned on the derivative 10 chromosome. The chromosome 10 breakpoint in our patient, as in other t(10;14), clusters within a 9 kb breakpoint region. The occurrence of seven breakpoints within a localized region of chromosome 10 implies the existence of a nearby gene whose activation may have conferred a selective advantage on the leukemia cells. Moreover, as in the previous cases, the translocation in the present study exhibits recombination signal sequences or signal-like sequences adjacent to the breakpoint junction. The presence of such motifs suggests the involvement of the recombinase enzyme system in the generation of this genetic alteration.
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PMID:A complex genetic rearrangement in a t(10;14)(q24;q11) associated with T-cell acute lymphoblastic leukemia. 137 7

A novel translocation, t(5;14)(q33-34;q11), was identified in the leukemic cells of four children presenting with acute lymphoblastic leukemia (ALL). The patients were 14 months, 2 years, 10 years, and 12 years old; each presented with one or more features of bulky disease, including lymphadenopathy, organomegaly or a mediastinal mass. The leukemic blasts were B lineage in two cases and T lineage in two cases. The patients with B-lineage ALL remain in continuous remission at 22 and 19 months following diagnosis. One patient with T-lineage ALL relapsed 6 months after diagnosis. The other patient with T-lineage ALL developed acute myelocytic leukemia (AML) 17 months after diagnosis; t(5;14)(q33-34;q11) was present in both the lymphoblasts at diagnosis and the myeloblasts at relapse, consistent with a lineage switch from ALL to AML. Rearrangement of the T-cell receptor delta chain (TCRD) gene at 14q11 was demonstrated in the three cases studied, suggesting its involvement in the pathogenesis of these leukemias by alteration of the structure or expression of an unidentified gene(s) on the long arm of chromosome 5.
Leukemia 1994 Sep
PMID:t(5;14)(q33-34;q11), a new recurring cytogenetic abnormality in childhood acute leukemia. 809 32

Umbilical cord blood (CB) has been used as a valuable source of hematopoietic stem cells for allogeneic transplantation, specific CTL response and immunotherapy for decades. We previously analyzed the distribution and clonality of T-cell receptor alpha and beta variable region (TRAV) and (TRBV) of the subfamily T cell receptors in T cells from umbilical cord blood. Recent data indicated that gammadelta(+) T cells may play an important role in mediating the graft versus leukemia effect after stem cells transplantation and in anti-cancer response. In order to further characterize the repertoire of CB T-cells, the frequency of alphabeta(+) and gammadelta(+) T cells were examined in CB by FACS. The CDR3 size of 4 TRGV and 8 TRDV subfamily genes were analyzed in mononuclear cells (MCs) from 16 CB samples, using RT-PCR and genescan technique. To determine the expression level of TRGV subfamily genes, we performed quantitative analysis of TRGVI-III subfamilies by real-time PCR. Low percentage of CD3(+)TCRgammadelta(+) cells was observed in CB. The frequency of expression in TRGVI, TRGVII and TRGVIII in CBMCs was 93.75%, 81.25% and 56.25%, respectively. The mean value of the number of expressed TRDV subfamilies in CBMCs is higher than that from adult peripheral blood (PB) group. The frequently expressed members in CB were TRDV1 (100%), TRDV2 (93.75%), TRDV8 (93.75%) and TRDV3 (81.25%), respectively. The frequencies of TRDV5 and TRDV8 in CBMCs were significantly higher than those from PBMCs. Most of the PCR products of TRGV and TRDV subfamilies from 10 CB samples displayed polyclonal rearrangement pattern, whereas one or two PCR products from 6 CB samples showed oligoclonality or biclonality. In contrast, PCR products from 9 of 10 adult healthy controls contained at least an oligoclonal peak in different TRGV or TRDV subfamilies respectively. The pattern of TRGV subfamily expression level in CBMCs was TRGVI>TRGVIII>TRGVII, and in contrast, TRGVII>TRGVI>TRGVIII was found in PBMCs. In conclusion, our results indicate polyclonal and more diverse TRDV segment usage in CB gammadelta(+) T-cells. The pattern of TRGV expression levels in CB T cells was found to be quite different from the one in PB T cells. These findings are apparently the first report regarding the repression pattern of TRGV repertoire in CB. It also provides a detailed profile of the global TRGV and TRDV repertoire and TRGVI-III expression levels in cord blood T cells in Chinese subjects. The biological significance of the differences observed between CB and PB is at present obscure. However, this study will definitively contribute to understand the cellular immune features better and to exploit more efficiently the therapeutic potentials of CB.
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PMID:TRGV and TRDV repertoire distribution and clonality of T cells from umbilical cord blood. 1901 41