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Query: UMLS:C0019829 (
Hodgkin's disease
)
30,247
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
The protein p27KIP1 belongs to a recently identified family of proteins termed cyclin-dependent kinase inhibitors (CDKIs). These proteins play an important role in regulating cell-cycle progression and loss of their function has been implicated in tumorigenesis. Transforming growth factor beta (TGF-beta) may induce cell growth arrest through
p27
activation. TGF-beta often loses its ability to arrest growth of transformed cells; this could potentially occur through a defect in
p27
. To determine the role of
p27
in tumorigenesis, we examined its mutational status in 74 non-
Hodgkin
's lymphomas (NHLs) (52 of B-cell phenotype, 22 of T-cell phenotype), 5 lymphoma cell lines, and 42 adult T-cell leukemias/lymphomas (ATLs) using polymerase chain reaction-single strand conformational polymorphism (PCR-SSCP) and Southern blot analyses. A nonsense mutation (stop codon) that could result in expression of a truncated nonfunctional
p27
protein was detected at codon 76 in one case of acute lymphomatous ATL, but not in matched normal tissues. Previously undescribed polymorphisms were also identified at codon 109 in the lymphomas and at codon 55 in the ATLs. Two homozygous deletions of the
p27
gene were detected in one case of B-immunoblastic NHL and in one case of acute ATL by Southern blot hybridization. These results indicate that
p27
gene alterations are rare events in NHLs and ATLs, but may play an important role in the pathogenesis of some hematologic malignancies.
...
PMID:Alterations of the p27KIP1 gene in non-Hodgkin's lymphomas and adult T-cell leukemia/lymphoma. 765 21
Cyclin-dependent kinase inhibitors (CDKIs) can be classified into two groups based on the structure of the proteins. One group includes the p21 (CIP1, WAF1, CAP20),
p27
(Kip1), and p57 (Kip2) CDKIs, which contain a homologous amino-terminal cyclin-dependent kinase (cdk) inhibitory domain. The p16 (INK4A), p15 (INK4B), and p18 (INK4C) CDKIs, which have an ankyrin repeat motifs, belong to the other group. The p16 and p15 CDKI genes are very frequently altered in a variety of cancers including hematopoietic malignancies. The p19 (INK4D) gene is a newly cloned CDKI which belongs to the latter group. To determine if p19 genetic alterations play a role in hematopoietic malignancies, we examined DNA from 45 childhood newly diagnosed acute lymphocytic leukemias (ALLs), 30 acute myeloblastic leukemias (AMLs), 10 chronic myelocytic leukemias (CMLs), 45 adult T cell leukemias (ATLs), 70 non-
Hodgkin
's lymphomas (NHLs), and 20 multiple myelomas (MM) as well as 14 ALL, 20 AML, two ATL, and five lymphoma cell lines. Using Southern blot analysis, one homozygous deletion of the p19 gene was detected in a human immunodeficiency virus (HIV)-related Burkitt-like lymphoma sample. No point mutations in any of the samples were found by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. Our investigation suggests that alterations of p19 do not play an important role in the development of most hematopoietic malignancies.
...
PMID:Alterations of the cyclin-dependent kinase inhibitor p19 (INK4D) is rare in hematopoietic malignancies. 894 28
The protein p27Kip1 is one of the cyclin-dependent kinase inhibitors that are known to play important roles in the regulation of cell-cycle progression. Low levels of
p27
expression in malignant cells are associated with poor prognosis in patients with breast, lung, colorectal and gastric cancers. To determine the relation of cyclin-dependent kinase inhibitors to histopathological grades of B-cell non-
Hodgkin
's lymphomas, the expression of
p27
, cyclin D1 and cyclin E in lymph node tissues was investigated in 56 patients with B-cell non-
Hodgkin
's lymphomas by western blotting and immunohistochemical techniques. High levels of
p27
expression were observed in most lymph node tissue samples (93%) obtained from patients with low grade B-cell non-
Hodgkin
's lymphomas, while expression was low in lymph node tissue taken from all patients with intermediate and high grade B-cell non-
Hodgkin
's lymphomas. The difference in
p27
expression in lymphoma tissues was significant among the different histopathological grades of B-cell non-
Hodgkin
's lymphomas (P<0.01). The analysis of the survival time of patients showed that the reduction of
p27
expression correlated with poor prognosis. Cyclin D1, showed a high level of expression in mantle cell lymphomas and high grade B-cell non-
Hodgkin
's lymphomas. Cyclin E showed limited expression in 18 of 31 lymphoma tissues. Both cyclin D1 and E protein expression were not significantly different among the grades of B-cell non-
Hodgkin
's lymphomas. These results demonstrate that the level of
p27
expression in lymphoma tissue is an important parameter in the classification of B-cell non-
Hodgkin
's lymphomas and in the prediction of prognosis.
...
PMID:Protein expression of cell cycle regulator, p27Kip1, correlates with histopathological grade of non-Hodgkin's lymphoma. 1062 39
Chronic B-cell lymphocytic leukaemia (CLL) and low-grade B-cell Non
Hodgkin
's lymphomas (Lg-NHL) are characterized by slow accumulation of neoplastic cells arrested in the G0/G1 phase of the cell cycle. In contrast, proliferation rates are high in aggressive B-cell lymphomas (Hg-NHL). Divergent expression of cyclin-dependent kinase inhibitors (CKI) in the cell cycle may contribute to these differences. We analysed CLL as well as low and high grade B-cell NHL for expression of G1-specific and universal CKI by competitive RT-PCR and immunostaining. p16(INK4A) expression was low in all types of neoplasms. Highest p14(ARF) /p16 beta expression levels were found in normal lymphocytes. Expression of this CKI was significantly lower in CLL, but still higher in CLL than in the lymphomas (median 27 vs. 3 mRNA transcripts x 10(3), p = 0.0001). p14(ARF) /p16 beta immunostaining correlated with mRNA expression. Highest p21 mRNA levels were found in CLL, but three of four CLL with abundant p21 mRNA production were negative on immunostaining. High grade lymphomas showed markedly decreased p21 expression (3.9 in Hg-NHL vs. 12 in Lg-NHL and 29 in CLL; values expressed as mRNA transcripts x 10(3), p < 0.009). mRNA and protein expression of
p27
was considerably higher in CLL than in the lymphomas. Differential CKI expression in various B-cell neoplasias may provide important biological markers, if not the molecular underpinning of their different cell cycle kinetics. Targeted interference with such genes governing cell cycle control in lymphoid neoplasia may pave the way towards new treatment strategies.
...
PMID:Divergent expression of cyclin-dependent kinase inhibitors (CKI) and p14ARF/p16 beta in non-Hodgkin's lymphomas and chronic lymphocytic leukemia. 1104 28
Monocytoid B cells (MBCs) are a subset of B cells that may be recognized in several reactive and tumoral lymph node conditions, including toxoplasmic lymphadenitis, infectious mononucleosis, and
Hodgkin's lymphoma
. Although this is a commonly observed cell population, which has even given its name to a type of lymphoma, MBC lymphoma, scarcely any information is available about the function and characteristics of this cell type. A relationship with marginal zone (MZ) B lymphocytes has been claimed for MBCs, but this has not yet been fully proven. Indeed, specific markers for MBCs are still lacking, which has made it difficult to analyze their relationship with other B cell subpopulations and confirm the existence of tumors deriving from this B cell subset. We used a panel of cell cycle markers to explore the characteristics of MBCs and their relationship with MZ B cells, nodal MZ lymphoma, and splenic MZ lymphoma. We therefore compared the phenotypic profile of MBCs in different conditions with normal MZ B cells within the spleen and mesenteric lymph nodes, with a group of seven cases of nodal MZ/MBC lymphoma and another group of five cases of splenic MZ lymphoma. MBCs were mainly in the G(0) to G(1) phases, as deduced from the presence of a proportion of between 10 and 35% Ki67-positive cells, whereas very low expression was observed with cyclin A and cyclin B staining. Nests of MBCs were clearly labeled by the expression of p21(WAF1), a cyclin-dependent kinase inhibitor (CKI), rarely detectable in benign lymphocytes, and by cyclin E. Basically all MBCs were bcl-2-negative, and high cyclin D2 and cyclin D3 were also detected in these cells, at proportions and intensities above expected levels, when the percentage of proliferating cells was taken into account. p27(KIP1) expression was characterized by homogeneous reactivity, higher than that observed in other B cell populations with a relatively high-growth fraction. Immunoglobulin staining showed undetectable light and heavy chains. However, splenic MZ cells, nodal MZ lymphoma, and splenic MZ lymphoma showed a distinct expression of IgM and bcl-2, with high
p27
(KIP1) nuclear expression and undetectable or low levels of cyclin A, B, E, or D, or p21(WAF1) expression. The data from this study show an unexpected immunophenotype in MBCs, different from the one observed in splenic and lymph node MZ B cells. This suggests that either MBCs are a unique B cell population from a distinct cell lineage, or if related to MZ cells, they would represent a definite differentiation stage characterized by a distinctive immunophenotype. They also show so-called MZ/MBC lymphoma to be more closely related to lymph node and splenic MZ B cells, as they do not share the most distinctive features of MBCs.
...
PMID:Unique phenotypic profile of monocytoid B cells: differences in comparison with the phenotypic profile observed in marginal zone B cells and so-called monocytoid B cell lymphoma. 1129 May 54
The distinction between mantle cell lymphoma (MCL) and other small B-cell non-
Hodgkin
lymphomas (NHL) is important because MCL has a more aggressive clinical course. In bone marrow (BM) biopsy specimens, this distinction can be particularly difficult. Although cyclin D1 immunostaining and molecular detection of the t(11;14) translocation are highly specific markers for MCL, they fail to detect a proportion of cases. We have recently described that MCL typically lacks detectable expression of the cyclin-dependent kinase inhibitor p27(kip1) protein by immunostaining, which is expressed at high levels in most small B-cell NHL inversely correlated to the proliferation rate. We therefore examined whether
p27
(kip1) immunostaining could be a useful adjunct for the differential diagnosis of small B-cell NHL infiltrates in the BM. Trephine BM biopsy specimens of 96 patients, including well-characterized MCL (19 cases), B-cell chronic lymphocytic leukemia (27 cases), follicular lymphoma (18 cases), hairy cell leukemia (22 cases), and marginal zone lymphoma (10 cases) as well as 10 reactive BM, including five with benign lymphoid aggregates were investigated. In addition, the presence of a t(11;14) translocation involving the major translocation cluster was studied by PCR in all MCL. All cases of B-cell chronic lymphocytic leukemia, follicular lymphoma, and marginal zone lymphoma revealed a strong
p27
(kip1) nuclear staining in the majority of neoplastic cells. Fourteen (78%) cases of MCL were
p27
(kip1)-negative in the tumor cells, whereas four cases revealed a weak nuclear positivity. Seventeen (77%) cases of hairy cell leukemia were also either completely negative for
p27
(kip1) or showed a faint positive staining in a minority of the neoplastic cells. Nine of 19 cases (47%) of MCL showed a bcl1 rearrangement involving the major translocation cluster region. These findings demonstrate that
p27
(kip1) immunostaining is a valuable additional marker for the differential diagnosis of small B-cell NHL infiltrates in BM biopsies. The reduction or lack of
p27
(kip1) protein expression in MCL, as well as in hairy cell leukemia, might be an important event in the pathogenesis of these disorders.
...
PMID:p27(Kip1) immunostaining for the differential diagnosis of small b-cell neoplasms in trephine bone marrow biopsies. 1159 73
Knowledge of the role of cell-cycle regulators in the pathogenesis of acquired immune deficiency syndrome-related non-
Hodgkin
's lymphomas (AIDS-NHLs) is scarce. Here we analyzed 86 systemic AIDS-NHLs and 20 AIDS-primary central nervous system lymphomas for expression of
p27
(Kip1), a negative regulator of cell-cycle progression belonging to the Kip family of cyclin-dependent kinase inhibitors. In parallel, we investigated the relationship between
p27
(Kip1), the lymphoma proliferation index, Epstein-Barr virus status, expression of cellular cyclin D3 and cyclin D1, and B-cell differentiation stage. We report that AIDS-immunoblastic lymphomas (AIDS-IBLs), either systemic or primarily localized to the central nervous system, consistently express
p27
(Kip1) protein (19 of 24 and 10 of 14, respectively) despite the high proliferative rate of the lymphoma clone, suggesting a failure of
p27
(Kip1) to inhibit the cell cycle in AIDS-IBL. Conversely, the remaining systemic AIDS-NHLs and AIDS-primary central nervous system lymphomas preferentially fail to express
p27
(Kip1). Expression of
p27
(Kip1) in Epstein-Barr virus-positive AIDS-NHLs generally associates with latent membrane protein 1 (LMP1) expression and is related to a late stage of B-cell differentiation, characterized by the BCL-6-/MUM1+/syn-1+/- phenotypic profile, whereas it seems to be unrelated to the expression of cellular cyclins. In B cells in vitro, induction of LMP-1 expression under the control of inducible promoters up-regulates expression of
p27
(Kip1), thus providing a putative mechanistic explanation for the association between LMP1 and
p27
(Kip1) observed in vivo. Overall, these data show that AIDS-IBL pathogenesis is characterized by loss of the inverse relationship between
p27
(Kip1) positivity and tumor growth fraction that is otherwise generally observed in normal lymphoid tissues and in most other types of NHLs.
...
PMID:Expression of cyclin-dependent kinase inhibitor p27(Kip1) in AIDS-related diffuse large-cell lymphomas is associated with Epstein-Barr virus-encoded latent membrane protein 1. 1210 1
Absence of a reliable method for determining the level of c-myc expression has impeded the analysis of its biological and clinical relevance in tumors. We have standardized the conditions for a real-time reverse transcription polymerase chain reaction analysis for c-myc expression, including the selection of an endogenous reference (18S rRNA), the adequate number of measurements for each sample (2 cDNA in triplicate), and suitable controls for determining inter- and intrarun variability (standard curve and calibrator). Subsequently, in a series of 56 non-
Hodgkin
's lymphomas, we analyzed the expression of c-myc mRNA, using real-time reverse transcription polymerase chain reaction, and of other functionally related proteins (bcl-6,
p27
, cyclin D3, and p53). As expected, all eight Burkitt's lymphoma cases analyzed had high levels of c-myc mRNA expression compared with that observed in reactive lymphoid tissue. There was a wider range of expression in diffuse large B-cell lymphoma, with 30% (15 of 48) of cases overexpressing c-myc. This overexpression was largely independent of c-myc translocations (4 of 5), as demonstrated by fluorescence in situ hybridization. In this large B-cell lymphoma series, a high level of c-myc expression predicted lower survival probability, irrespectively of the International Prognostic Index risk group classification. A slightly increased frequency of p53 inactivation was observed in the cases with c-myc overexpression, which suggests a growth advantage in lymphomas with concurrent deregulation of c-myc and p53. In addition, a moderate increase in bcl-6 protein expression was observed in the c-myc-positive cases, suggesting the existence of a complex interrelationship between these two genes. These findings suggest that c-myc may play a relevant role in the pathogenesis of a subset of large B-cell lymphoma and suggest the existence of additional regulatory mechanisms of c-myc expression to c-myc rearrangements.
...
PMID:Development of a real-time reverse transcription polymerase chain reaction assay for c-myc expression that allows the identification of a subset of c-myc+ diffuse large B-cell lymphoma. 1259 30
Cell cycle regulation is often altered in cancer and deregulation of the cell cycle checkpoints is common in human neoplasia. The dual-specificity phosphatase Cdc25A and the cell cycle inhibitor
p27
both play an important role in the regulation of the G1-S transition. We evaluated Cdc25A mRNA expression by in situ hybridization and
p27
protein expression by immunohistochemistry in 42 histologically indolent B-cell non-
Hodgkin lymphoma
(NHL and 51 histologically aggressive B-cell NHL. Overexpression of Cdc25A (>50% tumor cells positive) was detected in 5 of 42 cases (12%) of histologically indolent B-cell NHL and in 29 of 51 (57%) of histologically aggressive B-cell NHL (P < 0.001). In contrast, high
p27
protein expression (>50% tumor cells positive) was observed in 29 (69%) cases of indolent but in only one case (2%) of aggressive B-cell NHL (P < 0.0001). Thus, overexpression of Cdc25A and concomitant loss of
p27
expression are associated with high grade B-cell NHL and may contribute to their aggressive biologic behavior.
...
PMID:Reciprocal Cdc25A and p27 expression in B-cell non-Hodgkin lymphomas. 1296 Jun 94
There is accumulating evidence that
Hodgkin
's and Reed-Sternberg cells of classical
Hodgkin
's lymphomas (cHL) display multiple and concurrent alterations in different pathways and checkpoints of the cell cycle. However, the expression of cyclin D2 and its relation to other major cell cycle proteins has not been analyzed in cHL. The aim of the present study was to assess expression of cyclin D2, Ki67, cyclin A, cyclin B1, cyclin D1, cyclin D3, cyclin E, p53, Rb, p16 and
p27
proteins in order to gain further insight into the proliferation profile of cHL. Overexpression of cyclin D2 in
Hodgkin
's and Reed-Sternberg cells was detected in 64/89 (72%) cases of cHL. This finding, in view of recent in vitro data showing that constitutive activation of nuclear factor (NF)-kB could upregulate cyclin D2 expression in part via signal transducer and activator of transcription (STAT)-5a, suggests that induction of cyclin D2 expression may support the proliferation of
Hodgkin
's and Reed-Sternberg cells. In addition, the present study showed that (1) increased
p27
expression status was significantly correlated with higher levels of cyclin A expression (P=0.048) and (2) increased p53 expression status was significantly correlated with higher levels of cyclin A (P<0.001) and cyclin B1 (P=0.040) expression. The association between increased
p27
and p53 expression status and higher expression levels of G2/M cyclins suggests that the impairment of the growth inhibitory activity of the
p27
and p53 tumor suppressor pathways may promote the proliferation of
Hodgkin
's and Reed-Sternberg cells.
...
PMID:Proliferation profile of classical Hodgkin's lymphomas. Increased expression of the protein cyclin D2 in Hodgkin's and Reed-Sternberg cells. 1535 86
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