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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 etiology and pathogenesis of
Hodgkin lymphoma
(HL) are not yet known. There are implications of genes involved in programmed cell death (apoptosis), and there have been repeated suggestions of an association with Epstein-Barr virus (EBV). The aim of this study was to investigate the protein expression patterns of key cell cycle-related genes, together with evidence of apoptosis and EBV status, in relation to clinical stage in HLs. A double immunohistochemical and in situ hybridization technique was used to detect the expression of bcl-2, p53, retinoblastoma (Rb), p21, Ki67 (MIB 1), and
topoisomerase
IIalpha (TopoIIalpha), together with latent membrane protein-1 and EBER for EBV status and TdT-mediated dUTP-FITC nick end-labeling (TUNEL) as a measure of apoptosis, on tissue microarray sections of 62 cases of classic HL (35 NS, 17 MC, 8 LR, and 2 LD). A panel of phenotypic markers was used to facilitate recognition of
Hodgkin
and Reed-Sternberg (H-RS) cells: CD3, CD20, CD30, CD15, and EMA. The H-RS cells of 62 classic
Hodgkin
lymphomas were bcl-2-positive in 35 cases (56.45%), p53-positive in 14 (22.58%), and positive for both EBV latent membrane protein-1 and EBER in 37 (59.68%); there was complete concordance of results for EBV by both procedures. No correlation was found between expression of bcl-2, p53, or EBV markers in H-RS cells and clinical stage (P > 0.05). Expression of Rb, Ki67, p21, and TopoIIalpha did, however, show significant differences with clinical stage. Expression of Rb and p21 in CD30-positive H-RS cells decreased with more advanced stage (P < 0.001). In contrast, Ki67 and ToPoIIalpha expression increased with later stage (P < 0.01). No correlation was found between expression of any of these markers in H-RS cells and the subtypes of nodular sclerosis HL, mixed cellularity HL, and LRHL (P > 0.05). TUNEL was found in the nonneoplastic cellular background in all cases and in H-RS cells in only 10 of 62 cases (16.12%) (8 nodular sclerosis HL, 1 mixed cellularity HL, and 1 LRHL). There was a significant correlation between high expression of bcl-2 and a low score by TUNEL (P < 0.05). These data are consistent with the notion that overexpression of bcl-2 may be linked to blockage of apoptosis-mediated death of H-RS cells in classic HL. Abnormal expression of p53-related protein may not play a major role in HL, because it is present in H-RS cells in only a minority of cases. Increased expression of Ki67 and TopoIIalpha by H-RS cells is significantly associated with advanced stage and may indicate aggressive disease. Adverse clinical outcome in HL also is associated with loss of Rb and p21 protein expression, consistent with the possible roles of Rb and p21 in inhibition of the growth of H-RS cells. Within the limitations of the methods used, almost two thirds of cases of HL provide evidence of an association with EBV. The tissue microarray technique is valuable not only for examination of large numbers of cases of a disease by a complex panel of markers but also potentially as a control for staining quality in immunohistochemistry and in situ hybridization.
...
PMID:Apoptosis and cell cycle-related genes and proteins in classical Hodgkin lymphoma: application of tissue microarray technique. 1296 46
Etoposide is a derivative of podophyllotoxin widely used in the treatment of several neoplasms, including small cell lung cancer, germ cell tumours and non-
Hodgkin
's lymphomas. Prolonged administration of etoposide aims for continuous inhibition of
topoisomerase
II, the intracellular target of etoposide, thus preventing tumour cells from repairing DNA breaks. However, the clinical advantages of extended schedules as compared with conventional short-term infusions remain unclear. Oral administration of etoposide represents the most feasible and economic strategy to maintain effective concentrations of drug for extended times. Nevertheless, the efficacy of oral etoposide therapy is contingent on circumventing pharmacokinetic limitations, mainly low and variable bioavailability. Inhibition of small bowel and hepatic metabolism of etoposide with specific cytochrome P450 inhibitors or inhibition of the intestinal P-glycoprotein efflux pump have been attempted to increase the bioavailability of oral etoposide, but the best results were obtained with daily oral administration of low etoposide doses (50-100 mg/day for 14-21 days). Saturable absorption of etoposide was reported for doses greater than 200 mg/day, whereas lower doses were associated with increased bioavailability, although they were characterised by high inter- and intrapatient variability. Pharmacokinetic parameters such as plasma trough concentration between two oral administrations (C(24,trough)), drug exposure time above a threshold value and area under the plasma concentration-time curve have been correlated with the pharmacodynamic effect of oral etoposide. Pharmacokinetic-pharmacodynamic relationships indicate that severe toxicity is avoided when peak plasma concentrations do not exceed 3-5 mg/L and C(24,trough) is under the threshold limit of 0.3 mg/L. To maintain effective etoposide plasma concentrations during prolonged oral administration, pharmacokinetic variability must be monitored in each patient, taking account of factors from many pharmacokinetic studies of etoposide, including absorption, distribution, protein binding, metabolism and elimination. Dosage reduction is generally useful to avoid haematological toxicity in patients with renal dysfunction (creatinine clearance <50 mL/min). The need for dosage adjustment based on liver function in patients with liver dysfunction is not completely defined, but generally is not indicated in patients with minor liver dysfunction. Adaptive dosage adjustment based on individual pharmacokinetic parameters, estimated using limited sampling strategies and population pharmacokinetic models, is more appropriate. This approach has been used with success in different clinical trials to increase the etoposide dosage, without significantly increasing toxicity. Various pharmacodynamic models have been proposed to guide etoposide oral dosage. However, they lack precision and accuracy and need to be refined by considering other predictor variables in order to extend their application in current clinical practice.
...
PMID:Pharmacokinetic optimisation of treatment with oral etoposide. 1513 94
Pixantrone is an anthraquinone-based inhibitor of
topoisomerase
II. It is similar to both the anthracycline doxorubicin and the anthracenedione mitoxantrone, but lacks the 5,8-dihydroxy substitution pattern of mitoxantrone, and has a tricyclic system unlike the tetracyclic structure seen with anthracyclines. Anthracyclines are the most active drugs in lymphoma therapy, but their use is limited by their cumulative and irreversible cardiotoxicity. Pixantrone was developed to improve the toxicity profile of the current anthracyclines and anthracenediones while maintaining their activity. Interestingly, pixantrone showed no measurable cardiotoxicity compared with its parent compound mitoxantrone or other anthracyclines at equi-effective doses in several animal models. Together with its superior cytotoxic activity in leukaemia and lymphoma models, these features render the drug a promising candidate for clinical development in indolent and aggressive non-Hodgkin's lymphoma. In this review, the latest results of the use of pixantrone in indolen-t and aggressive non-
Hodgkin
's lymphomas are summarised.
...
PMID:The role of pixantrone in the treatment of non-Hodgkin's lymphoma. 1605 Jul 97
Topoisomerase enzymes are critical components of genomic replication and function to minimize torsional stress on DNA. Sequential administration of a
topoisomerase
II inhibitor followed by a topoisomerase I inhibitor is potentially synergistic due to increased target enzyme levels. Patients with relapsed or refractory aggressive non-
Hodgkin
's lymphomas (NHL) were eligible for this phase II study of doxorubicin 25 mg/m2 intravenous (IV) on day 1 and topotecan 1.75 mg/m2/day IV on days 3 - 5, every 21 days. The trial objectives included the overall response rate, progression-free survival, and toxicity. Twenty-six patients were enrolled and 25 patients are assessable for toxicity and response. The median age was 58 (range 23 - 74) years. The patients had received a median of two (range one to five) prior regimens, including five patients with a prior stem cell transplant. Five patients (20%, 95% confidence interval 0.07, 0.42) responded with two (8%) complete remissions and three (12%) partial remissions; an additional four (16%) patients had stable disease. Both patients achieving a complete remission had Burkitt's lymphoma. There were no treatment-related deaths. In conclusion, the combination of doxorubicin and topotecan is well tolerated and has modest activity in relapsed/refractory NHL, with occasional patients having a prolonged remission. The activity in Burkitt's lymphoma should be investigated further.
...
PMID:Sequential doxorubicin and topotecan in relapsed/refractory aggressive non-Hodgkin's lymphoma: results of CALGB 59906. 1696 61
Constitutive nuclear factor kappaB (NF-kappaB) activation characterizes
Hodgkin
/Reed-Sternberg (H-RS) cells. Blocking constitutive NF-kappaB has been shown to be a potential strategy to treat
Hodgkin lymphoma
(HL). Here, for the first time we show that although constitutive NF-kappaB level of H-RS cell lines is very high,
topoisomerase
inhibitors further enhance NF-kappaB activation through IkappaB kinase activation in not only H-RS cell lines with wild-type IkappaBalpha, but also in those with IkappaBalpha mutations and lacking wild-type IkappaBalpha. Thus, both constitutive and inducible NF-kappaB are potential targets to treat HL. We also present the data that indicate the involvement of IkappaBbeta in NF-kappaB induction by
topoisomerase
inhibitors. A new NF-kappaB inhibitor, dehydroxymethylepoxyquinomicin (DHMEQ) inhibited constitutive NF-kappaB activity and induced apoptosis of H-RS cell lines. DHMEQ also inhibited the growth of H-RS cells without significant systemic toxicity in a NOD/SCID/gammac(null) (NOG) mice model. DHMEQ and
topoisomerase
inhibitors revealed enhancement of apoptosis of H-RS cells by blocking inducible NF-kappaB. Results of this study suggest that both constitutive and inducible NF-kappaB are molecular targets of DHMEQ in the treatment of HL. The results also indicate that IkappaBbeta is involved in NF-kappaB activation in H-RS cells and IkappaBbeta substitutes for IkappaBalpha in H-RS cells lacking wild-type IkappaBalpha.
...
PMID:IkappaBalpha independent induction of NF-kappaB and its inhibition by DHMEQ in Hodgkin/Reed-Sternberg cells. 1731 Feb 17
Epidemiological studies show that benzene exposure is associated with an increased incidence of leukemia and perhaps lymphoma. Chromosomal rearrangements are common in these hematopoietic diseases. Translocation t(14;18), the long-arm deletion of chromosome 6 [del(6q)], and trisomy 12 are frequently observed in lymphoma patients. Rearrangements of the MLL gene located on chromosome 11q23, such as t(4;11) and t(6;11), are common in therapy-related leukemias resulting from treatment with
topoisomerase
II inhibiting drugs. To examine numerical and structural changes in these chromosomes (2, 4, 6, 11, 12, 14, and 18), fluorescence in situ hybridization (FISH) was employed on metaphase spreads from workers exposed to benzene (n = 43) and matched controls (n = 44) from Shanghai, China. Aneuploidy (both monosomy and trisomy) of all seven chromosomes was increased by benzene exposure. Benzene also induced del(6q) in a dose-dependent manner (P(trend) = 0.0002). Interestingly, translocations between chromosomes 14 and 18, t(14;18), known to be associated with follicular non-
Hodgkin lymphoma
, were increased in the highly exposed workers (P < 0.001). On the other hand, translocations between chromosome 11 and other partner chromosomes that are found in therapy-induced leukemias were not increased. These data add weight to the notion that benzene can induce t(14;18) and del(6q) found in lymphoma, but do not support the idea that benzene induces t(4;11) or t(6;11). However, they do not rule out the possibility that other rearrangements of the MLL gene at chromosome 11q23 may be induced by benzene.
...
PMID:Aberrations in chromosomes associated with lymphoma and therapy-related leukemia in benzene-exposed workers. 1758 86
Therapy-related myelodysplastic syndrome/acute myeloid leukemia (t-MDS/AML) is an increasingly recognized treatment complication in patients treated with radiotherapy or chemotherapy for previous hematologic malignancies or solid tumors. Distinct clinical entities have been described according to the primary treatment, corresponding to defined genetic lesions. Chromosome 7 and/or 5 losses or deletions are typical of alkylating agent-induced AML, while development of t-AML with balanced translocations involving chromosome bands 11q23 and 21q22 has been related to previous therapy with drugs targeting DNA-
topoisomerase
II. In addition, antimetabolites, and in particular the immunosuppressant azathioprine, have been shown to induce defective DNA-mismatch repair. This could promote survival of misrepaired cells giving rise to the leukemic clone. Individual predisposing factors, including polymorphisms in detoxification and DNA repair enzymes have been identified. Their combination may significantly increase the risk of t-MDS/AML. Among patients with hematologic malignancies, long-term survivors of
Hodgkin's lymphoma
are exposed to an increased risk of t-MDS/AML, particularly when receiving MOPP-based, and escalated BEACOPP regimens, and when alkylators are combined with radiotherapy. Patients with
Hodgkin
's and non-Hodgkin's lymphoma are at highest risk when total body irradiation followed by autologous stem cell transplantation is used as rescue or consolidation therapy. The addition of granulocyte-colony-stimulating factor and radiotherapy plays a significant role in t-AML following treatment of children with acute lymphoblastic leukemia. In non-hematologic malignancies, treatment for breast cancer and germ-cell tumors has been associated with a 1-5% lifetime risk of both lymphoid as well as myeloid leukemia. In all cases the risk of t-MDS/AML drops sharply by 10 years after treatment.
...
PMID:Therapy-related leukemia and myelodysplasia: susceptibility and incidence. 1776 13
The outcome of classical
Hodgkin lymphoma
(cHL) patients may be related to the tumor microenvironment, which in turn may be influenced by Epstein-Barr virus (EBV) infection. To characterize the cHL microenvironment, a set of 63 cHL tissue samples was profiled using DNA microarrays. Their gene expression profile differed from that of histiocyte T cell-rich B-cell lymphoma (H/TCRBCL) samples that were used as controls, mainly due to high expression of PDCD1/PD-1 in H/TCRBCL. EBV(+) cHL tissues could be distinguished from EBV(-) samples by a gene signature characteristic of Th1 and antiviral responses. Samples from cHL patients with favorable outcome overexpressed genes specific for B cells and genes involved in apoptotic pathways. An independent set of 146 cHL samples was analyzed using immunohistochemistry. It showed a significant adverse value in case of high percentage of either TIA-1(+)-reactive cells or
topoisomerase
-2(+) tumor cells, whereas high numbers of BCL11A(+), FOXP3(+), or CD20(+) reactive cells had a favorable influence. Our results suggest an antitumoral role for B cells in the cHL microenvironment and a stronger stromal influence of the PD1 pathway in H/TCRBCL than cHL. The observation of Th1/ antiviral response in EBV(+) cHL tissues provides a basis for novel treatment strategies.
...
PMID:Molecular profiling of classical Hodgkin lymphoma tissues uncovers variations in the tumor microenvironment and correlations with EBV infection and outcome. 1909 12
Therapy-related myeloid neoplasms (t-MN) include acute myeloid leukemias and myelodysplastic syndromes arising in patients who have been treated with chemotherapy, radiation therapy, immunosuppressive agents or after documented exposure to environmental carcinogen. t-MN are defined according to the primary treatment and the corresponding genetic and molecular lesions. Chromosome(s) 7 and/or 5 monosomies or deletions are typical of alkylating agent-induced AML, while balanced translocations involving chromosome bands 11q23 and 21q22 are associated to preceeding therapy with DNA-
topoisomerase
II inhibitors. Antimetabolites, and in particular the immunosuppressive agents azathioprine and fludarabine, have also been recently associated to t-MN. Leukemias developing after benzene exposure are similar to t-MN and are characterized by chromosomal aberrations, which have been also observed among otherwise healthy benzene-exposed workers. Individual predisposing factors, including polymorphisms of detoxification and DNA-repair enzymes have been identified. Two genetic variants in key metabolizing enzymes, myeloperoxidase and NAD(P)H:quinone oxidoreductase, have been shown to influence susceptibility to benzene hematotoxicity. Combination of polymorphisms impairing detoxification and DNA repair may significantly increase therapy-related myeloid neoplasm risk. Among hematological malignancies, long-term survivors of
Hodgkin's lymphoma
are exposed to an increased t-MN risk, particularly when receiving MOPP-based and escalated-BEACOPP regimens, and when alkylators are combined to radiotherapy. Patients with lymphoma are at highest risk if total body irradiation followed by autologous stem cell transplantation is used as rescue or consolidation. The addition of granulocyte-colony stimulating factor (G-CSF) and radiotherapy plays a significant role in t-MN following treatment of childhood acute lymphoblastic leukemia. In solid tumors, treatment for breast cancer and germ-cell tumors has been associated with a 1-5% lifetime risk of t-MN.
...
PMID:Incidence and susceptibility to therapy-related myeloid neoplasms. 2002 17
Secondary malignancies (SMs) in
Hodgkin lymphoma
(HL) are thought to be related to exposure to alkalating agents,
topoisomerase
II inhibitors and ionizing radiation, and tend to occur a decade after initial therapy. We report a 14 year old autistic male, who developed malignant fibrous histiocytoma (MFH) two years after autologous stem cell transplantation for advanced stage HL. The MFH and post-surgical reactive tissues exhibited multiple clonal abnormalities. In addition, PHA-stimulated peripheral blood lymphocytes showed increased frequency of non-clonal chromosomal aberrations. The potential role of genomic instability in early onset of SM in our patient is discussed.
...
PMID:Malignant fibrous histiocytoma two years after autologous stem cell transplant for Hodgkin lymphoma: evidence for genomic instability. 2148 63
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