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)

Cyclin D1/PRAD1 (bcl-1) is a recently discovered proto-oncogene that is overexpressed in mantle cell lymphomas and several other human tumors. In a previous study, the authors demonstrated expression of cyclin D1 in 15 of 15 cases of mantle cell lymphoma and 1 of 8 cases of B-chronic lymphocytic leukemia (B-CLL) using a polyclonal antibody and microwave enhanced immunohistochemical staining method on paraffin-embedded tissue sections. In this study, 107 additional B- and T-cell neoplasms were studied, including 47 cases of high grade lymphoma (33 diffuse large B-cell type, 9 Burkitt and Burkitt-like, 4 precursor T-lymphoblastic lymphoma, and 1 adult T-cell lymphoma/leukemia), 38 additional cases of low grade B-cell lymphoma (18 CLL, 15 hairy cell leukemia and 5 mantle cell lymphoma), and 22 plasmacytomas for expression of cyclin D1 using the same immunohistochemical staining technique. All cases of mantle cell lymphoma showed diffuse nuclear staining. No additional cases of CLL showed cyclin D1 expression. In contrast, 1 of 15 hairy cell leukemias and 1 of 22 plasmacytomas showed cyclin D1 staining. None of the high grade lymphomas demonstrated expression of cyclin D1 protein by immunostaining, including three cases of large B-cell lymphoma that coexpressed CD5. The authors conclude that cyclin D1 is expressed in all cases of mantle cell lymphoma, and only in very rare cases of B-CLL, hairy cell leukemia and plasmacytoma/myeloma. Cyclin D1 does not appear to play an important role in high grade lymphomas. In addition, most CD5 positive high grade B-cell lymphomas do not express cyclin D1, and are not likely to be derived from mantle cell lymphoma or other lymphomas with t(11;14).
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PMID:Cyclin D1 expression in non-Hodgkin's lymphomas. Detection by immunohistochemistry. 754 Mar 62

The PRAD-1/CCND1 gene encodes Cyclin D1, a cyclin involved in cell cycle regulation at the G1-S transition. Over-expression of this gene is a highly specific molecular marker of mantle cell lymphomas (MCLs), but it may also be up-regulated in some chronic lymphoproliferative disorders, mainly chronic lymphocytic leukaemia. We have examined PRAD-1/CCND1 gene expression by Northern blot and Western blot analysis in a series of 18 hairy cell leukaemias (HCLs), nine other splenic malignant lymphoproliferative disorders, and three normal/reactive spleens. Over-expression of the mRNA PRAD-1/CCND1 gene was observed in 16/18 HCLs, including one case of hairy cell leukaemia variant, whereas this molecular alteration was not found in other cases examined. mRNA levels varied from case to case, but they were lower than those observed in MCLs. At the protein level, Western blotting analysis showed Cyclin D1 protein expression in the 11 HCLs analysed. No bcl-1 rearrangements were seen with the MTC, p94PS and PRAD-1 (lambda-P1-4) probes used, and no PRAD-1/CCND1 gene amplification was detected in any case. These findings indicate that PRAD-1/CCND1 is over-expressed at mRNA and protein levels in a high number of HCLs. However, the levels of expression are much lower than in MCLs, and this expression is not associated with bcl-1 rearrangements or PRAD-1/CCND1 gene amplification.
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PMID:Increased expression of the PRAD-1/CCND1 gene in hairy cell leukaemia. 854 15

Mantle cell lymphoma is a B cell lymphoproliferative disorder cytogenetically characterized by the t(11;14)(q13;q32) which at molecular level involves the Bcl-1/PRAD-1 gene. Immunophenotypically it is characterized by co-expression of CD5+/CD20+ and CD23- antigens. Histologic patterns are recognized as: diffuse, mantle zone and nodular. Diffuse mantle lymphoma is the most frequent and is associated with a poor prognosis. The rearrangement of the Bcl-1/PRAD-1 increases the synthesis of cyclin D1. Cyclin D1 binds to Cdk4 and forms a complex, then binds to and phosphorylates Rb protein thus triggering cells to progress from G0/G1 to S and thus drives cellular proliferation. The 5-year survival in the MD Anderson series was less than 30% and anthracycline regimens do not appear to have any major impact on the outcomes of cases with nodular or diffuse histopathological patterns. Intensive therapeutic programs and first line autologous or allogeneic bone marrow transplantation remains experimental.
Leukemia 1996 Jun
PMID:Mantle cell lymphoma: a lymphoproliferative disorder associated with aberrant function of the cell cycle. 864 59

Abnormalities of several cell-cycle regulatory genes including cyclin D1, p16CDKN2 and p15CDKN2B have been described in B cell non-Hodgkin's lymphoma (B-NHL). We describe a new B-NHL cell line (Granta 519), with concurrent abnormalities of the cyclin D1, pl6CDKN2 and pl5CDKN2B genes. An independent clinical case of mantle cell NHL (Mc-NHL) with concomitant overexpression of cyclin D1, and deletion of the p16CDKN2 gene was also identified, suggesting that this combination of oncogenic aberration is a pathophysiologic contribution to a subset of NHL cases. More in-depth functional studies of this concept were facilitated by the availability of the cell line Granta 519 which was derived from a case of high-grade NHL and has a mature B cell immunophenotype. Cytogenetic analysis identified translocation t(11;14)(q13;q32) and complex rearrangements involving chromosomes 9p22, 13p21, 17pl1, and 18q21. Molecular analysis identified overexpression of cyclin D1 mRNA and biallelic deletion of the p16CDKN2 and p15CDKN2B genes. To elucidate the effect of these genetic abnormalities on the G1 control of Granta 519 cells, the level and function of the major components of the cyclinD/retinoblastoma (RB) pathway were investigated. Cyclin D1 was dominant among the D-type cyclins, formed abundant complexes with cyclin-dependent kinase (Cdk) Cdk4 rather than Cdk6, and the immunoprecipitated cyclin D1/Cdk4 holoenzyme was active as a pRB kinase. Electroporation of wild-type pl6CDKN2 arrested the Granta 519 cells in G1, consistent with the p16CDKN2 loss as a biologically relevant event during multistep evolution of the tumor, and with the expression of functional pRB. Direct cooperation of these distinct abnormalities to cell-cycle, deregulation in NHL cells was suggested by G1 acceleration upon inducible overexpression of cyclin D1 in a control breast cancer cell line lacking p16CDKN2, an effect which could be prevented by ectopic expression of p16CDKN2. Taken together, these data suggest that concurrent overexpression of cyclin D1 and functional elimination of p16CDKN2 and p15CDKN2B may characterize certain cases of mantle cell NHL, and that cooperation of the abnormalities is likely to provide a growth advantage of the tumour cells through more efficient inactivation of the RB tumor suppressor. Further clinicopathologic studies of this possibility are warranted.
Leukemia 1997 Jan
PMID:Potential role for concurrent abnormalities of the cyclin D1, p16CDKN2 and p15CDKN2B genes in certain B cell non-Hodgkin's lymphomas. Functional studies in a cell line (Granta 519). 900 20

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

We previously reported that all-trans retinoic acid (RA) and fenretinide (4HPR) suppress HL-60 leukemia cell growth and cause partial cell arrest in the G1-to-S phase. Moreover, 4HPR but not RA induces apoptosis in HL-60 cells. To investigate further the observed biological effects, cyclin D1 and cdk4 expression and the level of phosphorylation of the retinoblastoma protein Rb were assessed. Cyclin D1 and cdk4 expression and Rb phosphorylation were significantly reduced, by 40-75%, after 24 hr of treatment with RA or 4HPR; these decreases were either transient, e.g., only at 24 hr for cdk4, or sustained for 72 hr. In general, more pronounced decreases were seen in the 4HPR-treated cells. Evidence for 4HPR-induced apoptosis comes from (1) cleavage of the enzyme poly(ADP-ribose) polymerase (PARP) to an 89-kDa truncated product, (2) appearance of DNA ladders on agarose gel electrophoresis, and (3) higher incorporation in situ of digoxigenin nucleotides into the free 3'-ends of DNA. Overnight pretreatment with 0.5-5.0 microM of the CPP32 inhibitor DEVD, but not the ICE inhibitor YVAD, significantly reduced the specific processing of PARP, suggesting that CPP32 is involved in the mechanism of action of 4HPR. Analysis of 2 lipid-derived second messengers, ceramide and diacylglycerol (DAG), as a function of time of treatment with RA or 4HPR, showed ceramide but not DAG to be significantly albeit transiently increased 2-fold at 3 hr, by 4HPR. To test further whether ceramide may be involved in the signaling cascade that culminates in the induction of apoptosis in 4HPR-treated HL-60 cells, the effects of fumonisin B1, an inhibitor of ceramide synthase, were studied. Simultaneous treatment of cells with 4HPR and 25-100 microM fumonisin B1 resulted in a dose-dependent reduction in the elevation in ceramide, the extent of PARP cleavage, and induction of apoptosis. Pretreatment with DEVD or YVAD, on the other hand, had no effect on the 4HPR-induced increase in ceramide.
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PMID:Regulation of G1/S transition and induction of apoptosis in HL-60 leukemia cells by fenretinide (4HPR). 972 94

We used genetic strategies which have been proven valuable to decipher signaling pathways in comparatively simple organisms such as Drosophila and Caenorhabditis elegans, to dissect signaling network activated by tyrosine kinases in mammals. The strategy was developed further towards a generally applicable expression cloning system to identify signal transducers in tyrosine kinase pathways. This system is based on the ability of downstream acting genes to rescue the transformation phenotype of partial loss-of-function mutants of BCR-ABL which still retain tyrosine kinase activity. Using this strategy we have previously shown that overexpression of c-Myc and Cyclin D1 can rescue a signaling defective SH2 mutant of BCR-ABL for transformation. In an unbiased approach to identify new compensating genes, a cDNA library was introduced by retroviral infection into fibroblasts which express the BCR-ABL SH2 mutant. CDNA clones, capable of rescuing the SH2 mutant for transformation should result in colony formation in soft agar. A PCR approach was used to recover these compensating genes from the genomic DNA of the transformed fibroblasts. Sequencing analysis of the initial cDNAs identified three known genes, the adapter molecule Shc, the kinases SPRK and p38 MAPK. These genes have been found to interact functionally with BCR-ABL for fibroblast and hematopoietic cell transformation. Currently, we are constructing and screening new libraries to identify novel genes which complement the BCR-ABL SH2 mutant. Our results demonstrate that this cloning approach is an effective means of identifying and characterizing signaling molecules that function in specific signaling pathways. This in turn may identify specific targets for mechanism-based therapeutic intervention to block altered signaling.
Leukemia 1998 Dec
PMID:Dissection of signaling pathways and cloning of new signal transducers in tyrosine kinase-induced pathways by genetic selection. 984 16

Cyclin D1 participates in cell-cycle control, in the progression through the G(1) phase and in the transition from the G(1) to the S phase. The CCND1 locus, located in 11q13, is amplified and cyclin-D1 protein is over-expressed in a wide range of human solid tumors. In some B-lymphoid malignancies, the t(11;14)(q13;q32) translocation joins the Ig heavy-chain locus to the CCND1 locus and leads to cyclin-D1 over-expression. In this study, a series of 127 patients presenting a B-chronic lymphoproliferative disorder (B-CLPD) was analyzed using a competitive RT-PCR designed to detect cyclin-D1-mRNA over-expression. Cyclin-D1 mRNA was expressed in patients with mantle-cell lymphoma (MCL; 10/10), hairy-cell leukemia (HCL; 3/5), B-chronic lymphoid leukemia (B-CLL; 4/111) and B large-cell lymphoma (BLCL; 1/1). Densitometric analysis of RT-PCR products and Western-blot autoradiograms, in addition to cytogenetic data, indicated that activation of the cyclin-D1 gene occurred independently of the t(11;14)(q13;q32) translocation in patients with HCL. Indeed, a normal-sized protein of 36 kDa exhibiting a level incompatible with gene activation by a translocation mechanism was detected in lymphoid cells with a normal karyotype. Moreover, we found a discrepancy between cyclin-D1 mRNA and protein levels in MCL and B-CLL, which suggested that some regulatory mechanisms acting at a post-transcriptional level persist in tumor cells.
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PMID:Transcriptional and post-transcriptional mechanisms induce cyclin-D1 over-expression in B-chronic lymphoproliferative disorders. 1047 32

Cyclin D1 is a weak oncogene that cooperates with c-myc activation in the development of B cell lymphomas in transgenic animals. Cyclin D1 is constantly overexpressed in human mantle cell lymphomas (MCL). However, the status of c-myc gene in these tumors is not known. We have examined the c-myc mRNA expression and genomic alterations, including mutational analysis of exon 1, intron 1, and exon 2 regulatory elements, in a series of 33 MCL, 22 typical and 11 blastoid variants. In addition, c-myc alterations were also examined in 56 nodal non-Hodgkin's lymphomas (NHL). c-myc mRNA overexpression was found in 38% (11/29) of MCL with a slightly higher frequency in blastoid variants (5/10, 50%) than in typical cases (6/19, 31%). Genetic alterations were only found in one blastoid MCL showing a three-fold c-myc gene amplification. In other nodal NHL, c-myc overexpression was found in 24% (7/29) of indolent tumors but in 70% (19/27) of aggressive variants. c-myc Genetic alterations detected in these cases were gene rearrangement and hypermutations in one Burkitt's lymphoma, and individual point mutations in intron 1 or exon 2 in 1/19 (5%) indolent and 7/16 (44%) aggressive variants. These results indicate that c-myc is overexpressed in a subset of MCL, but structural gene alterations are less frequent than in other nodal NHL.
Leukemia 1999 Dec
PMID:c-myc mRNA expression and genomic alterations in mantle cell lymphomas and other nodal non-Hodgkin's lymphomas. 1060 33

Mantle cell lymphoma (MCL) is a tumor of intermediate-size, IgM+, IgD+ B cells derived from the mantle zone of the germinal center. Little is known about its specific immunologic features or responsiveness to T cell-derived signals. In this work, we evaluated the proliferation and cell cycle properties of freshly isolated MCL cells after CD40 ligation, in the absence and presence of interleukin 4 (IL-4). In each MCL case examined, there was a marked growth-enhancing effect of these two stimuli characterized by improved viability, augmented expression of Ki-67, and induction of the proliferating cell nuclear antigen (PCNA). Cyclin D1 was expressed throughout the cell cycle in MCL cells induced to enter S phase. From these investigations, we conclude that the biology of MCL B lymphocytes is affected by CD154 (CD40 ligand) and IL-4, two signals usually provided by CD4+ T cells. The capacity to manipulate the activation and cell cycle state of MCL cells by these specific immunological stimuli may be exploited to confer susceptibility to chemotherapy agents and develop novel therapies in this disease.
Leukemia 2000 Feb
PMID:Proliferative response of mantle cell lymphoma cells stimulated by CD40 ligation and IL-4. 1067 47


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