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J Pris

Publications and source records attributed to J Pris.

At least 19 recordsLinked to original sources

Frequent expression of the cell death-inducing gene Bax in Reed-Sternberg cells of Hodgkin's disease.

The expression of a cell death-inducing gene, Bax, was investigated in 52 cases of Hodgkin's disease in parallel with Epstein-Barr virus and was compared with the immunodetection of other apoptosis-regulating proteins, Mcl-1, Bcl-2, and Bcl-x. Bax immunostaining was found in 92% of the cases, among them 28% with a strong signal in more than 75% of the Reed-Sternberg cells. Mcl-1 was positive in 80% of the cases, whereas Bcl-2 and Bcl-x were found in 53% and 88% of the cases, respectively. Of 48 (89%) Bax-positive tumors, 43 were found to express apoptosis-inhibiting proteins such as Mcl-1 or Bcl-2. With the exception of 1 case, all Bax-positive tumors also expressed either Bcl-2, Bcl-x, Mcl-1, or combinations of these anti-apoptotic proteins. No correlation was found between Bax expression and the presence of apoptotic cells as detected by morphology and the in situ 3' OH-DNA end-labeling technique. Our findings show that the apoptosis-inducing gene Bax expression is frequently expressed in Hodgkin's disease, providing a potential explanation for the good chemoresponses generally obtained for patients with this neoplastic disorder.

Apoptosis

Vincristine degradation by serum from leukemic patients: role of myeloperoxidase.

Myeloperoxidase (MPO) has been shown to catalyze the in vitro degradation of vincristine (VCR). Given that MPO is a lysosomal enzyme that can be released into the circulation by both normal activated and leukemic myeloid cells, we investigated the possibility that sera from patients with acute myeloblastic leukemia (AML) might exhibit an increased capacity to degrade VCR. 31 serum samples (23 from patients with acute myeloblastic leukemia and 8 from patients with other conditions) were analyzed after incubation with ((3)H)VCR by using HPLC. Sera from patients with AML demonstrated an increased ability to breakdown VCR when compared to either normal sera or to sera from patients with lymphoid leukemias. VCR degradation was significantly increased by adding hydrogen peroxide, an electron donor for MPO, to the sera and was almost completely inhibited by adding 1 mM acetaminophen, an inhibitor of MPO. VCR peroxidation in the presence of hydrogen peroxide correlated both with the number of leukemic blasts in the circulation at the time the sera were obtained and with serum MPO concentrations determined by an immunoassay. These data suggest that the inactivity of VCR in AML may be due in part to its rapid peroxidation to inactive species by the MPO of leukemic myeloblasts.

Acetaminophen

Bcl-x gene expression in Hodgkin's disease.

Bcl-x is a Bcl-2-family protein that has been previously detected in cortical thymocytes, plasma cells, and activated lymphocytes. We report here on the high detection rate of the Bcl-x protein found in 86% of Hodgkin's disease samples and on the significance regarding its complex role among the Bcl-2-family of proteins: Bcl-x is known to heterodimerize with Bcl-2 (an anti-apoptosis protein) and with Bax, a potent inducer of cell death. Moreover, recent evidences show that Bcl-x may induce multiple drug resistance in vitro, suggesting that chemical or biological interactions with this protein may have potential therapeutic value in Hodgkin's disease.

Apoptosis

A prospective randomized trial of idarubicin vs daunorubicin in combination chemotherapy for acute myelogenous leukemia of the age group 55 to 75.

A prospective randomized study was conducted comparing the efficacy and toxicity of two anthracyclines for the treatment of patients with acute myeloid leukemia (AML) between 55 and 75 years. A total of 220 patients were randomized to receive as induction chemotherapy cytosine arabinoside (Ara-C: 100 mg/m2/day; continuous infusion for 7 days) combined with either daunorubicin (DNR: 50 mg/m2/day, i.v. bolus for 3 days) (n=108) or idarubicin (IDA: 8 mg/m2/day, i.v. bolus for 5 days) (n=112). The complete remission (CR) rate was similar (P=0.296) after IDA (76/112; 68%) and DNR (66/108; 61%) (P=0.3). For patients aged 55-65, the CR rate was significantly higher after IDA (39/47; 83%) than after DNR (29/50; 58%) (P=0.007). Persistent leukemia was more frequent after DNR (26/108) than after IDA (13/112; P=0.015). Hematological and extra-hematological toxicities were similar. The CR patients were given a consolidation course of chemotherapy with Ara-C: 50 mg/m2/12 h, subcutaneously for 5 days, combined with either DNR:30 mg m2/day, i.v. bolus for 3 days or IDA:8 mg/m2/day i.v. bolus for 3 days according to the initial randomization, and then received a continuous maintenance treatment for 2 years. The survival and disease-free survival (DFS) were similar in both groups; there was no difference in the risk of relapse. However, there was a trend for a longer event-free survival (EFS) in the IDA group than for the DNR patients (P=0.07). Our results seem to indicate that IDA is probably more efficient than DNR for AML patients between 55 and 75 years, and confirm the data published in other studies comparing prospectively IDA and DNR in adults.

Aged

Immunodetection of apoptosis-regulating proteins in lymphomas from patients with and without human immunodeficiency virus infection.

The expression of the apoptosis-regulating genes Bcl-2, Bcl-x, Bax, Mcl-1, and p53 analyzed in 4 cases of human immunodeficiency virus (HIV)-associated Hodgkin's disease, in 36 cases of HIV-related non-Hodgkin's lymphomas (NHLs), and in 109 cases of non-HIV-related NHLs by using immunohistochemistry. HIV-associated Hodgkin's disease samples were positive for all markers. For the HIV-related NHL samples, 36, 66, 88, 100, and 94% of the cases were Bcl-2, Bcl-x, Bax, Mcl-1, and p53 were found to be expressed in 69, 65, 82, 83, and 42%, respectively. No significant differences were observed in Bax and Mcl-1 staining between HIV-unrelated NHLs of B cell and T cell types. In contrast, Bcl-2 was positive in 66/79 (83%) and 10/30 (33%) of B cell and T cell HIV-unrelated NHLs, respectively (P2 < 0.001). Peculiar patterns were observed for hairy cell leukemia (Bax+, Bcl-2+, Mcl-1-) and for anaplastic large cell lymphoma (Bax+, Mcl-1+, Bcl-2-) in HIV-unrelated NHLs. Of interest, all cases with a positive expression of Bax were also found to express either Mcl-1 and/or Bcl-2, suggesting that Mcl-1 and Bcl-2 may counteract the pro-apoptosis function of Bax in vivo by protein-protein interaction within the tumor cell, as demonstrated previously in vitro. These results suggest that apoptosis regulation may have a role in the pathogenesis of some HIV-related and HIV-unrelated NHLs.

Apoptosis

Allogeneic vs autologous stem cell transplantation vs chemotherapy in patients with acute myeloid leukemia in first remission: the BGMT 87 study.

In 204 adult patients with de novo acute myeloid leukemia (AML), we prospectively compared allogeneic bone marrow transplantation (alloBMT), autologous stem cell transplantation (ASCT) and chemotherapy (Chemo). 162 patients (79.4%) achieved a complete remission (CR). Of the 135 patients who were still in CR after consolidation, 96 patients were less than 46 years of age: 36 patients had an HLA-identical sibling donor and were allocated for alloBMT (group I); they were compared to the 60 other patients who did not have an HLA-identical sibling donor and were treated with either ASCT or chemotherapy (group II). The 3-year disease-free survival was higher for group I patients (66.5 +/- 16%) than for the 60 group II patients (42.4 +/- 13%) (P < 0.05). The actuarial risk of relapse at 3 years was significantly lower for group I patients (24 +/- 15%) than for the other 60 group II patients (56 +/- 13%; P < 0.009). By multivariate analysis, the disease-free survival and risk of relapse were influenced by the initial WBC count (P < 0.02 and P < 0.006), the number of chemotherapy courses for CR (P < 0.001 and P < 0.01) and the type of post-induction treatment (alloBMT vs no alloBMT; P < 0.1 and P < 0.02). The 99 patients who did not fulfill the inclusion criteria for alloBMT were given intensive chemotherapy including high-dose aracytine. When they were still in CR (n = 77), these patients were then randomized for either ASCT (n = 39) or Chemo (n = 38). We were unable to detect any statistical difference between ASCT and Chemo for either disease-free survival, risk of relapse or survival. These results indicate that alloBMT seems to produce results which are at least superior to those of other therapeutic modalities. The results of either ASCT or Chemo look similar.

Acute Disease

High expression of the bcl-x gene in Reed-Sternberg cells of Hodgkin's disease.

The expression of bcl-x protein, a bcl-2-related protein present in cortical thymocytes, activated lymphocytes, and plasma cells of reactive lymph nodes, was investigated in 44 cases of Hodgkin's disease (HD) in parallel with bcl-2 and Epstein-Barr virus (EBV) status. Eighty-six percent of the cases were positive for bcl-x, among them 27% with a strong signal in more than 75% of the Reed-Sternberg cells. Positivity for bcl-x was found in, respectively, 100% and 92% of the nodular sclerosis and mixed cellularity subtypes, although 4 cases of lymphocyte predominance subtype were negative. This finding was in contrast with the weaker positivity for bcl-2 staining in 44% of the cases. EBV small RNAs were detected in 43% of the cases by using in situ hybridization. Of interest, 100% of the EBV-positive samples were positive for bcl-x, whereas only 38% of these cases were bcl-2 positive. Our findings show that the bcl-x gene expression is high in HD, suggesting that bcl-x may have a role in the pathogenesis of at least some cases of HD via apoptosis regulation.

DNA, Viral

Symptomatic osteonecrosis in recipients of nonautologous bone marrow transplants.

A retrospective study of 36 allogeneic bone marrow transplant recipients was conducted to determine the rate of occurrence of and risk factors for avascular osteonecrosis. Eight patients developed osteonecrosis, after a mean time interval of 18 months. Multiple sites were often involved (mean 2.37 per patient). Advanced roentgenologic lesions were present at diagnosis in most instances. The occurrence of osteonecrosis was not significantly correlated with the initial hematologic diagnosis, the preparative regimen, serum lipid abnormalities, presence of acute or chronic graft-versus-host disease, or corticosteroid therapy characteristics. Intraosseous blood vessels exhibited histologic lesions consistent with a role of graft-versus-host-disease vasculitis in the occurrence of osteonecrosis in nonautologous bone marrow transplant recipients.

Adolescent

Persistence of the same viral strain in early and late relapses of Epstein-Barr virus-associated Hodgkin's disease.

Twelve cases of relapsing Hodgkin's disease were investigated for the presence of Epstein-Barr virus (EBV). Of these, 7 cases contained EBV gene products (LMP1, EBER RNA) in the diagnostic Reed-Sternberg cells and variants at first presentation and at relapse(s), whereas 5 cases were negative at both first diagnosis and relapse. Among the 7 EBV-positive cases, material for DNA extraction was available in 2 cases at both diagnosis and relapse(s). Ig and T-cell receptor gene rearrangements displayed a germline configuration in the 2 cases. However, Southern blot analysis of the terminal repeats (TR) of EBV genome showed that, in 1 of the 2 cases, the fragment was of the same size at diagnosis and in the subsequent two relapses (1 early and 1 late). The second case contained monoclonal EBV genome at diagnosis, but the Southern analysis of the TR was negative at relapse. The latent membrane protein (LMP1) sequence analysis confirmed the persistence of a distinctive viral strain in each of the 2 cases with individual abnormalities within the carboxy terminal region (5 point mutations and a 30-bp deletion for the first case and 6 point mutations for the second case). The persistence of a given strain in early and late relapses is evidence towards the view that in Hodgkin's disease such relapses are related to a single residual tumor cell clone.

Adult

Epstein-Barr virus in familial Hodgkin's disease.

Hodgkin's disease (HD) has been found to be linked to Epstein-Barr virus (EBV). Familial HD (FHD) may be related to a possible unknown agent. We have determined whether EBV small RNAs (EBERs) were found in Reed-Sternberg cells from FHD. Five families were studied for histological subtype and EBER presence. There was a striking similarity in FHD subtypes of each family and 3/11 (27%) of the cases were EBER positive. In conclusion, EBV EBERs are only infrequently found in FHD and other factors including viruses different from EBV should be further investigated in FHD.

Female

bcl-2 proto-oncogene and Epstein-Barr virus latent membrane protein-1 expression in AIDS-related lymphoma.

The expression of bcl-2 protein and Epstein-Barr virus (EBV) latent membrane protein 1 (LMP-1) was investigated in 18 cases of lymphoma occurring in the acquired immunodeficiency syndrome (AIDS). EBV small RNAs were detectable in tumour cells in all cases by in situ hybridization with EBER oligonucleotides. LMP-1 expression was detected in 61% of the cases, and 55% were positive for bcl-2. Dual expression of LMP-1 and bcl-2 was found in 8/18 (44%) cases, while five cases (28%) expressed either LMP-1 or bcl-2 and five expressed neither. Thus, there was an inconsistent relationship between the presence of EBV and the expression of bcl-2. One LMP-1 negative case was found to express bcl-2 in reactive lymphocytes but not in lymphoma cells. No clinical features were found to correlate statistically with LMP-1 or bcl-2 expression in the tumour cells. However, CD4 counts at diagnosis were significantly lower in bcl-2 positive cases (P < 0.05). The respective roles of EBV LMP-1 and the expression of bcl-2 in lymphogenesis in AIDS patients remains complex and is not yet fully understood.

Adult

Escalating dose of mitoxantrone with high-dose cyclophosphamide, carmustine, and etoposide in patients with refractory lymphoma undergoing autologous bone marrow transplantation.

PURPOSE: We conducted a dose-finding study of mitoxantrone (MITO) in combination with high-dose cyclophosphamide, carmustine (BCNU), and etoposide (CBV) in refractory lymphoma undergoing autologous bone marrow transplantation (ABMT). The objective were to determine the following: (1) the maximum-tolerated dose of MITO, (2) the extramedullary toxicity of this regimen, (3) its antitumor activity, and (4) the pharmacokinetic characteristics of MITO at each dose level. PATIENTS AND METHODS: Escalating doses of MITO (15 to 90 mg/m2, single bolus infusion on day -8) followed by CBV were administered to 20 patients (mean age, 38.5 years) with refractory lymphoma. MITO concentrations were determined by high-performance liquid chromatography (HPLC). RESULTS: No toxic death occurred. The maximum-tolerated dose appears to be 75 mg/m2. Two of five patients treated with 90 mg/m2 developed severe organ toxicity, versus zero of 15 treated with doses up to 75 mg/m2. Duration of neutropenia was longer for patients treated with 90 mg/m2 (31.7 days) than for patients treated with doses up to 75 mg/m2 (22.1 days) (P < .05). A linear relationship was observed between administered dose of MITO and (1) plasma peak value, (2) area under the curve (AUC), and (3) plasma concentration on the day of marrow infusion (day 0). Hematologic toxicity was related to the terminal half-life (T1/2) of MITO, and day-0 plasma concentration. A high complete response (CR) rate was observed (60%), and eight of 11 (73%) patients treated with MITO > or = 60 mg/m2 achieved a CR. CONCLUSION: MITO (up to 75 mg/m2) and CBV can be administered with acceptable toxicity and a promising CR rate in this poor-risk population, justifying further phase II studies.

Adult

Antisense inhibition of myeloperoxidase increases the sensitivity of the HL-60 cell line to vincristine.

Myeloperoxidase (MPO), a heme-peroxidase found in the HL-60 myeloblastic cell line, is involved in vincristine (VCR) metabolism and the inactivation of this drug. We have examined whether decreased MPO activity correlated with increased sensitivity to VCR toxicity in myeloid leukemia cells. We have used MPO antisense RNA to reduce 60% of the MPO activity in the HL-60 cells. The MPO-deficient HL-60 cell line, C15, was significantly more sensitive to VCR than the parental MPO-positive cell line. Both cell lines were negative for P170-glycoprotein expression. Conversely, an MPO-positive C15 subclone was more resistant to VCR than the MPO-deficient C15 cell line. No significant differences in cytotoxic effects were observed between MPO-positive and MPO-deficient cells, following treatment with either daunorubicin or actinomycin D, two multidrug resistance-related drugs. These results strongly support an important role for MPO in VCR resistance in HL-60 cells. Antisense manipulation of the MPO content of myeloid cells could be of potential interest in leukemia treatment.

ATP Binding Cassette Transporter, Subfamily B, Mem

Potential strategies for circumventing myeloperoxidase-catalyzed degradation of vinca alkaloids.

Myeloperoxidase (MPO) has recently been shown in an in vitro, cell-free system to catalyze the peroxidative degradation of vincristine (VCR). Oxidation of VCR involves a ring fission between positions 20' and 21', and is thought to be facilitated by the presence of an hydroxyl (-OH) group at position 20'. We report here two different approaches, both with potential clinical application, to decrease MPO-catalyzed vinca degradation. Firstly, we tested the hypothesis that -OH substitution at position 20' increases vinca susceptibility to peroxidation by comparing the relative extent of degradation of vinorelbine (Navelbine or NVB), which lacks a 20' hydroxyl substitution, with that of VCR. As anticipated, NVB was significantly less susceptible to MPO-catalyzed peroxidation than was VCR (p < 0.01). Secondly, we screened an array of compounds that are in current clinical use for their ability to inhibit MPO. Acetaminophen, N-acetylcysteine, propylthiouracil, D-penicillamine, mefenamic acid, dapsone, and methimazole all inhibited MPO at clinically achievable concentrations. Insofar as increased MPO activity has been observed in patients with acute myeloid leukemia, these findings suggest potential strategies for improving the activity of vinca alkaloids in this disease.

Antineoplastic Agents

B-cell lymphoma following polycythemia vera: evidence for the involvement of two different clones.

We report here two patients with polycythemia vera (PV) who developed secondary non-Hodgkin's lymphoma (NHL). Both cases were high grade B-cell NHL. Cytogenetic analysis of bone marrow and lymph node was performed in each case and showed numerous chromosomal abnormalities. Of interest, chromosomal abnormalities of the PV and of the NHL clones were different, suggesting the possible involvement of two different clones. A 11q23 breakpoint was common between the two cases and the putative role of this breakpoint in the pathogenesis of the NHLs is discussed.

Aged

Prevention of regimen-related toxicities after bone marrow transplantation by pentoxifylline: a prospective, randomized trial.

Elevated levels of tumor necrosis factor alpha (TNF-alpha) have been reported to correlate with the development of transplant-related complications after bone marrow transplantation (BMT). In a recent phase I-II trial, oral administration of pentoxifylline (PTX), a xanthine derivative capable of downregulating TNF-alpha production in vitro, was reported to reduce morbidity and mortality in patients undergoing BMT. We conducted a prospective randomized trial of PTX therapy among 140 patients undergoing either allogeneic (n = 51) or autologous BMT (n = 89). Patients were randomized to receive (n = 70) or not receive (n = 70) oral PTX, 1,600 mg/d in four divided doses from day -8 until day + 100 post-BMT. The incidence of mucositis requiring morphine sulfate (MSO4) was similar in both groups (42.9%), with the mean number of days with MSO4 being 7.8 (SD = 3.4) in the PTX group versus 8.2 (SD = 3.4) in the control group (NS). The incidence of renal insufficiency was not affected by PTX administration (15.7% in the PTX group v 21.4% in the control group [NS]) and the highest serum creatinine value during the first 100 days post-BMT was 119 mumol/L (SD = 82.4) in the PTX group versus 103.9 mumol/L (SD = 57) in the control group (NS). The incidence of grade > or = 2 graft-versus-host disease was similar in each group (11/25 [44%] in the PTX group v 12/26 [46%] in the control group). No significant difference was observed in hematologic toxicity, transfusion requirements, duration of fever, and hepatic toxicity between the treatment groups. In conclusion, our study failed to show a prophylactic effect of PTX in transplant-related toxicities after BMT. On the basis of these findings, we cannot recommend that PTX be part of early mortality and morbidity prevention programs after BMT.

Adult