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 overexpression of PRAD1/cyclin D1 gene activated by the 11q13 translocation and its molecular counterpart BCL-1 rearrangement is frequently associated with mantle cell lymphomas (MCLs). Recently, we produced a monoclonal antibody, 5D4, against the PRAD1/cyclin D1 product, and demonstrated that the positive nuclear staining by this antibody correlates with PRAD1/cyclin D1 mRNA overexpression in MCLs. In the present study, we have immunohistochemically examined the cyclin D1 protein in a large series of 315 malignant lymphomas including 39 MCLs on paraffin sections. The nuclear positive pattern was found in 35 (90%) of 39 MCLs with an exceptional case of immunocytoma among the B-cell lymphomas examined. In the other cases, the positivity was absent or appeared to lie within the cytoplasm without nuclear staining. We therefore propose that the immunolocalization of cyclin D1 protein is an essential marker for the definite diagnosis of MCL.
Leukemia 1997 Apr
PMID:Immunostaining of PRAD1/cyclin D1 protein as a marker for the diagnosis of mantle cell lymphoma. 920 49

Human T-cell leukemia virus type 1 is etiologically linked to the development of adult T-cell leukemia and various human neuropathies. The Tax protein of human T-cell leukemia virus type I has been implicated in cellular transformation. Like other oncoproteins, such as Myc, Jun, and Fos, Tax is a transcriptional activator. How it mechanistically dysregulates the cell cycle is unclear. Previously, it was suggested that Tax affects cell-phase transition by forming a direct protein-protein complex with p16(INK4a), thereby inactivating an inhibitor of G1-to-S-phase progression. Here we show that, in T cells deleted for p16(INK4a), Tax can compel an egress of cells from G0/G1 into S despite the absence of serum. We also show that in undifferentiated myocytes, expression of Tax represses cellular differentiation. In both settings, Tax expression was found to increase cyclin D-cdk activity and to enhance pRb phosphorylation. In T cells, a Tax-associated increase in steady-state E2F2 protein was also documented. In searching for a molecular explanation for these observations, we found that Tax forms a protein-protein complex with cyclin D3, whereas a point-mutated and transcriptionally inert Tax mutant failed to form such a complex. Interestingly, expression of wild-type Tax protein in cells was also correlated with the induction of a novel hyperphosphorylated cyclin D3 protein. Taken together, these findings suggest that Tax might directly influence cyclin D-cdk activity and function, perhaps by a route independent of cdk inhibitors such as p16(INK4a).
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PMID:Human T-cell leukemia virus type 1 Tax and cell cycle progression: role of cyclin D-cdk and p110Rb. 958 3

The telomerase activity of various hematologic disorders, including malignant and non-malignant ones is discussed in this paper. In total of 137 cases, each positivity of telomerase activity was MDS = 17/51, overt leukemia from MDS = 6/15, AML = 17/21, ALL = 4/6, CML-CP (chronic phase) = 0/10, CML-BC (blastic crisis) = 4/4, MPD (myeloproliferative disease)-BC = 3/3, CLL = 1/10, MM (multiple myeloma) = 0/6, aplastic anemia = 3/5, essential thrombocytosis = 0/3, and polycythemia vera = 1/3. The MPD-BC showed very high level of telomerase activity as well as CML-BC cases. From the analysis for 18 cases of AML and/or malignant lymphoma patients, significant results showed that the expression of cyclin D/E was not related to telomerase activity in these hematologic disease, as was not the case with breast cancer which was reported formerly.
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PMID:[Analysis for telomerase activity in various hematologic disorders]. 961 44

The cyclin DI/PRAD1 oncogene, a key regulator of the G1 phase of the cell cycle, has been incriminated in the pathogenesis of human neoplasia. Cyclin D1 was also demonstrated to be identical to the long-sought bcl-1 oncogene in B-cell malignancies with the t(11;14)(q13;q32) translocation. We report here a small deletion in the 3'-untranslated portion of the cyclin D1 gene in leukemia cells of a patient diagnosed with B-chronic lymphocytic leukemia (CLL), associated with overexpression of the corresponding cyclin D1 mRNA. During a Northern blot survey of B-cell malignancies, we identified a patient whose CLL cells showed a marked increase in 1.5-1.6 kb cyclin D1 mRNA species. Subsequent Southern blot analysis showed that genomic DNA from the patient's cells contained an extra band in the EcoRI digest, suggesting that one allele of the cyclin D1 gene may be altered. Polymerase chain reaction (PCR) analysis of the genomic DNA and direct DNA sequencing clearly disclosed that one allele of the cyclin D1 gene was deleted in the 3'-untranslated region, which would contribute to an increased stability of its mRNA. Reverse transcription-polymerase chain reaction (RT-PCR) analysis and direct DNA sequencing revealed that the cyclin D1 mRNA was deleted at the corresponding region. This finding provides further evidence for a critical role of cyclin D1 in the pathogenesis of B-cell malignancies and highlights a novel mechanism, a small deletion in the 3'-untranslated region, responsible for deregulation of the cyclin D1 gene in oncogenesis.
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PMID:A small deletion in the 3'-untranslated region of the cyclin D1/PRAD1/bcl-1 oncogene in a patient with chronic lymphocytic leukemia. 962 42

Cyclin A is a cell cycle regulatory protein that functions in mitotic and S phase control in mammalian cells. However, in contrast to other G1 phase regulatory proteins, such as cyclin D, retinoblastoma protein and p16INK4A, cyclin A seems not to be commonly involved in tumorigenesis. Recently, a second human cyclin A--cyclin A1--has been identified. In contrast to cyclin A which is expressed throughout embryonic development and in adult tissue, the expression of cyclin A1 has been reported to be restricted to embryonic and germ line cells. We have confirmed the absence of cyclin A1 mRNA from normal peripheral blood leukocytes of seven healthy donors by single step reverse transcriptase-polymerase chain reaction (RT-PCR). Furthermore, we have examined the expression of cyclin A1 mRNA in 173 peripheral blood samples of 162 patients with various hematological malignancies. Cyclin A1 mRNA was detectable in 11 of 11 patients with acute myeloid leukemia, three of three patients with acute biphenotypic leukemia, eight of eight patients with myelodysplastic syndrome, 59 of 69 patients with chronic myelogenous leukemia (CML) at diagnosis, 13 of 15 patients with CML in blastic transformation, 10 of 18 patients with chronic lymphocytic leukemia, two of nine patients with essential thrombocythemia, and only two of 10 patients with acute lymphoblastic leukemia (ALL) with both cyclin A1 RT-PCR positive ALL leukemias being undifferentiated relapses. In addition, cyclin A1 mRNA was found in one of six leukapheresis products, harvested from individuals without hematological disorders. Taken together, cyclin A1 is expressed in the majority of myeloid and undifferentiated hematological malignancies as well as in normal hematopoietic progenitor cells. We conclude that cyclin A1, a protein potentially involved in G1/S phase progression of immature cells, might be necessary for proliferation of early hematopoietic progenitor cells and their leukemic counterparts being blocked at that stage of differentiation.
Leukemia 1998 Jun
PMID:Cyclin A1 is predominantly expressed in hematological malignancies with myeloid differentiation. 963 17

Emu-ret mice carrying an RFP/RET fusion gene under the transcriptional control of the immunoglobulin heavy chain enhancer develop B lineage leukemias/lymphomas. We have characterized B-cell development in these mice before the onset of clinical disease to determine the steps involved in leukemogenesis. Flow cytometry reveals that the CD45R+CD43(+)CD24(+)BP-1(+) late pro-B-cell population is markedly expanded in the bone marrow of 3- to 5-week-old Emu-ret mice. Compared with late pro-B cells from transgene-negative mice, Emu-ret late pro-B cells have a limited capacity to differentiate in interleukin (IL)-7 and a higher incidence of VDJ rearrangements, but a similar cell cycle profile. In contrast, CD45R+CD43(+)CD24(+)BP-1(-) early pro-B cells from 3- to 5-week-old Emu-ret mice, which also express the RFP/RET transgene, differentiate in IL-7 similarly to their normal counterparts. Furthermore, early pro-B cells from Emu-ret and transgene-negative mice have an identical pattern of growth inhibition when exposed to interferons (IFNs)-alpha/beta and -gamma, whereas, pro-B-cell leukemia lines derived from Emu-ret mice are markedly less sensitive to growth inhibition by these IFNs. In 13-week-old well-appearing Emu-ret mice, late pro-B cells upregulate CYCLIN D1 expression and downregulate CASPASE-1 expression in a pattern that correlates with the emergence of B precursor cells in the peripheral blood and the loss of other B lineage subsets in the bone marrow. Taken together, these results suggest that the expression of the RFP/RET transgene initially prevents the normal elimination of late pro-B cells with nonproductive rearrangements. Secondary events that simultaneously disturb the normal transcriptional regulation of genes involved in the control of the cell cycle and apoptosis may allow for subsequent malignant transformation within the expanded late pro-B-cell population.
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PMID:The evolution of B precursor leukemia in the Emu-ret mouse. 963 27

Mantle cell lymphoma (MCL) patients represent a difficult problem, sometimes to establish the diagnosis but mostly because of their refractoriness to standard lymphoma treatments. Which treatments to apply and to whom is not yet defined. In this study, we attempted to analyze the clinical features, to identify the major prognostic factors, and to evaluate the outcome of 121 MCL patients treated in our institution between 1979 and 1997. Clinical data, treatment modalities, and International Prognostic Index (IPI) score were evaluated. Median age was 63 years. Patients usually presented with advanced stage disease (87%), disseminated lymph nodes (57%), bone marrow involvement (79%), but with a good performance status (PS) (81%). Lymphocytosis >4000/microl and/or peripheral blood involvement was present in 36% of cases, and gastrointestinal disease in 18%. The t(11;14)(q13;q32) and/or bcl-1 rearrangement was detected in 47/57 studied cases. Median overall survival (OS) was 3.12 years and a longer survival was significantly associated with younger age (<70 years), good PS (<2), localized disease (stage I-II), fewer than two extra-nodal sites, absence of spleen or peripheral blood involvement, normal serum LDH and beta2-microglobulin levels, and hemoglobin level greater than 12 g/dl. However, the IPI failed to identify patients with longer OS and in a multiparametric analysis, only older age, hemoglobin less than 12 g/dl, poor PS, and blood involvement were associated with a poorer outcome. Treatment modalities had no impact on survival with 75% of patients relapsing or progressing. Our data showed that the poor outcome of MCL patients is mainly related to adverse patient characteristics, a highly disseminated tumor, and some unknown parameters associated with the refractoriness to standard therapy.
Leukemia 1998 Aug
PMID:Mantle cell lymphoma: a retrospective study of 121 cases. 969 85

Mantle cell lymphoma represent a clinicopathologically distinct entity of malignant non-Hodgkin's lymphoma (NHL) and are characterized by a specific chromosomal translocation t(11;14)(q13;q32) involving the cyclin D1 gene also designated as bcl-1/PRAD1 gene on chromosome 11 and the heavy chain immunoglobulin joining region on chromosome 14. We have established a PCR method to amplify t(11;14) junctional sequences in DNA from fresh frozen and paraffin-embedded tissue by bcl-1-specific primers in combination with a consensus immunoglobulin JH primer. A total of 65 cases histologically classified as mantle cell lymphoma (MCL) were analyzed for the presence of a t(11;14) translocation and monoclonal IgH-CDR3 rearrangements. From 26 patients with classical MCL and three cases with the anaplastic variant of MCL fresh frozen biopsy material was available for DNA extraction. We detected a bcl-1/JH rearrangement in 12 out of 29 samples (41%). In 36 cases paraffin-embedded lymph node tissue was the only source of DNA. In this material we found a bcl-1/JH rearrangement in six out of 31 samples with intact DNA (20%). To confirm the specificity of the PCR and to determine the bcl-1/JH junctional region sequences as clone-specific marker in individual patients we characterized the junctional DNA sequences by direct PCR sequencing in 16 cases. Interestingly we found that six bcl-1/JH junctions harbored DH segments in their N regions indicating that bcl-1/JH rearrangements can occur in a later stage of B cell ontogeny during which the complete VH to DH-JH joining or VH-replacement takes place. To investigate the suitability of IgH-CDR3 as sensitive molecular marker for those MCL patients in which a t(11;14) translocation can not easily be amplified, we additionally analysed 60 cases for the presence of monoclonally rearranged IgH genes by IgH-CDR3-PCR. A monoclonal IgH-CDR3 PCR product could be identified in 24 out of 29 fresh frozen samples (79%) whereas only 11 out of 31 samples (36%) with paraffin-derived DNA were positive. We demonstrate that automated fluorescence detection of monoclonal IgH-CDR3 PCR products allows the rapid and sensitive monitoring of minimal residual disease also in cases that lack a PCR amplifiable t(11;14) translocation. In combination with allele-specific primers the procedure may improve current experimental approaches for detection of occult MCL cells at initial staging and residual disease during and after therapy.
Leukemia 1998 Oct
PMID:Structure of Bcl-1 and IgH-CDR3 rearrangements as clonal markers in mantle cell lymphomas. 976 10

The two gene products of the CDKN2A gene, p16 and p19ARF, have recently been linked to each of two major tumour suppressor pathways in human carcinogenesis, the RB1 pathway and the p53 pathway. p16 inhibits the phosphorylation of the retinoblastoma gene product by cyclin D-dependent kinases, whereas p19ARF targets MDM2, a p53 inhibitory protein, for degradation. A deletion of CDKN2A would therefore disturb both pathways. To explore the p53 pathway genes as a functional unit in diffuse large B cell non-Hodgkin's lymphomas (DLCL), we wanted to see whether there exists mutually exclusiveness of aberrations of CDKN2A, MDM2 and p53, since this has not been analysed previously. We investigated 37 DLCL for aberrations of p15, p16, p19ARF, MDM2, and p53 at the epigenetic, genetic and/or protein levels. Homozygous deletion of CDKN2A was detected in seven (19%) of 37 tumours, and another three cases were hypermethylated at the 5' CpG island of p16. No point mutations were found in CDKN2B or CDKN2A. Immunohistochemical staining of formalin-fixed, paraffin-embedded tissue for p16 confirmed these results, as all tumours with alterations of CDKN2A were p16 immunonegative. We found p53 mutations in eight (22%) cases and MDM2 overexpression in 16 (43%) tumours. Twenty-three (62%) tumours had alterations of one or more p53 pathway components (p53, p19ARF and MDM2). Furthermore, 7/9 (78%) p16-immunonegative tumours showed co-aberration of p53 and/or MDM2. The lack of correlation between these aberrations suggests that DLCL acquire additional growth advantage by inactivating both of these critical regulatory pathways.
Leukemia 1999 Mar
PMID:Aberrations of the p53 pathway components p53, MDM2 and CDKN2A appear independent in diffuse large B cell lymphoma. 1008 36

We analysed PRAD1/cyclin D1 expression in 20 patients with plasma cell malignancy by Northern analysis. 6/17 multiple myeloma patients and 3/3 plasma cell leukaemia patients showed PRAD1/cyclin D1 expression. This incidence appeared to be higher than the expected incidence based on previous studies. Southern analysis did not show rearrangement of the bcl-1 region. Although there was no statistical difference, the PRAD1/cyclin D1 negative group showed a 1-year survival of 81.8%, 3-year survival of 45.5% and 5-year survival of 22.7%, and those for the PRAD1/cyclin D1 positive group were 63.5%, 16.9% and 16.9%, respectively. Further study is required to determine whether PRAD1/cyclin D1 expression is a prognostic factor.
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PMID:Expression of PRAD1/cyclin D1 in plasma cell malignancy: incidence and prognostic aspects. 1008 3


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