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V Ribrag

Publications and source records attributed to V Ribrag.

At least 55 records · Page 3Linked to original sources
PubMed1996

Sustained complete cytologic and molecular remission induced by donor leucocyte infusions alone in an acute myeloblastic leukaemia in relapse after bone marrow transplantation.

Therapeutic options for treatment of recurrence of leukaemia after allogeneic bone marrow transplantation (BMT) are limited. A beneficial effect of donor lymphocyte infusions (DLI) has not previously been described in acute myeloid leukaemia (AML) relapse. We report a case of AML with t(8;21), relapsing 3 months after BMT, who received DLI without adjuvant chemotherapy or growth factors. The patient developed acute GVHD and achieved a rapid complete remission of his AML by both cytologic and molecular criteria of at least 14 months duration, thereby showing that DLI for AML in relapse after BMT is an alternative therapeutic option.

Adult↗
PubMed1996

Aggressive acute CD3+, CD56- T cell large granular lymphocyte leukemia with two stages of maturation arrest.

In the majority of clonal expansions of CD3+ large granular lymphocytes (LGL), referred to as T-LGL leukemia, patients have a chronic disease, often manifested by severe neutropenia, rheumatoid arthritis, and mild to moderate splenomegaly. The characteristic leukemic phenotype is CD3+, CD8+, CD16+, CD57+ and CD56-. Here we report an unusual case of T-LGL (CD3cyt+, CD3surface-, CD16+, CD56-) with clinicopathological features (acute presentation, large tumor mass, and systemic illness with highLGL counts at diagnosis) similar to those described for patients with CD3-natural killer (NK)-LGL leukemia. Two distinct stages of maturation arrest were observed: in the lymph node abnormal cells were CD4+, CD8+ whereas the majority of circulating leukemic cells expressed only CD8. TCR gamma (TCR gamma) gene configuration demonstrated that these originated from the same T cell clone, suggesting a maturation process between the two populations, or preferential passage of CD8 single positive cells into the blood.

Adolescent↗
PubMed1996

Drug resistance mechanisms in chronic lymphocytic leukemia.

Peripheral blood samples from 18 patients with chronic lymphocytic leukemias (CLL) who were either untreated but who were later sensitive to chlorambucil (CLL S) or resistant to a combination containing doxorubicin, vincristine, cyclophosphamide and prednisone (CLL R) were studied for glutathione system, P-glycoprotein, PCNA and topoisomerase II expression. P-glycoprotein expression detected by an immunocytochemical technique using MRK 16 antibody was present at the same level in CLL S and CLL R. The percentage of cells positive for P-gp was below 5% in all samples tested. Topoisomerase IIalpha level was quantified by Western blot analysis. None of the 18 CLL samples had detectable topoisomerase IIalpha protein. In addition, 12 CLL were tested for PCNA staining and no samples had more than 1% of positive cells at immunocytochemical detection indicating that CLL cells were not engaged in the cell cycle. Some differences were found between CLL S and CLL R in the glutathione system. Glutathione concentration (GSH) and GST activity was the same in CLL S and CLL R. The glutathione-S-transferase (GST) isoenzyme profile was different in the two CLL groups. The mean GST-pi and GST-alpha quantitation were twice as high as in CLL R compared to CLL S, but this difference did not reach statistical significance because of large variations between CLL samples. A significant correlation was observed between GST-pi expression and GST activity using CDNB as the substrate. GST-mu was detected in only one of seven CLL before therapy and in six of 11 resistant to chemotherapy. No correlation was found between P-glycoprotein expression, GST activity and the different GST isoenzymes studied. These results suggest that the glutathione system could play a role in the resistance of anticancer agents in chronic lymphocytic leukemia. The role of the other drug resistance mechanisms (P-glycoprotein and topoisomerase IIalpha) seems to be of limited importance.

ATP Binding Cassette Transporter, Subfamily B, Mem↗
PubMed1995

Chemotherapy combined with zidovudine and GM-CSF in human immunodeficiency virus-related non-Hodgkin's lymphoma.

OBJECTIVE: The treatment of patients with non-Hodgkin's lymphoma related to the human immunodeficiency virus (HIV-NHL) is complicated by the underlying acquired immunodeficiency syndrome (AIDS). Patients without adverse prognostic factors (no AIDS prior to lymphoma, CD4+ lymphocyte counts greater than 100 x 10(6)/l and good performance status) can be cured of lymphoma and experience long-term survival. Our previous study with the intensive chemotherapy LNH84 regimen yielded a 63% complete response (CR) rate but median survival was only nine months, half of the patients died of AIDS and the other half of their lymphoma. We report here the results of a phase II study combining the same chemotherapy with zidovudine and GM-CSF. Our goal was to improve the treatment outcome over that of our previous study; GM-CSF was expected to decrease the hematological toxicity of chemotherapy and thus permit a dose intensity increase, while zidovudine was supposed to slow down the evolution of AIDS. DESIGN AND SETTING: A phase II non-randomized prospective clinical trial in 7 centres. PATIENTS AND METHODS: Thirty-two consecutive adult patients presenting HIV-NHL and performance status of less than three without active opportunistic infection underwent three cycles of doxorubicin 75 mg/m2, cyclophosphamide 1,200 mg/m2, vindesine 2 mg/m2 for two days, bleomycin 10 mg for two days and prednisolone 60 mg/m2 for five days (ACVB). Chemotherapy was associated with zidovudine (5 mg/kg/d) and GM-CSF (5 mu g/kg/d). The induction phase was followed by a four-month consolidation phase. RESULTS: CR and PR > 75% were observed in 56% of patients; 25% of the patients died during the induction phase. These results were analogous to those of the previous study (63% and 14%, respectively). Neither hematological tolerance nor dose intensity were improved. With a mean follow-up of 23.5 months, median survival was 6.7 months. The rate of non-NHL AIDS-related death during CR was not reduced (22% in our study vs. 16% in our previous one). CONCLUSIONS: GM-CSF failed to reduce significantly the cumulative hematological toxicity of chemotherapy and zidovudine. New antiviral agents without hematological toxicity would perhaps be useful in this setting.

Adolescent↗
PubMed1995

Main drug-metabolizing enzyme systems in human non-Hodgkin's lymphomas sensitive or resistant to chemotherapy.

Non-Hodgkin's lymphomas (NHL) are one of the most chemosensitive human malignancies. Complete response (CR) is often achieved, but many patients relapse and a second CR is difficult to obtain because of the development of chemoresistance. In an attempt to better understand the biology and the chemosensitivity of these lymphoid tumors, we assessed the main drug-metabolizing enzyme systems in normal lymphocytes, chemosensitive NHL and chemoresistant NHL. Cytochromes P-450 (1A1/A2, 2B1/B2, 2C8-10, 2E1, 3A4), epoxide hydrolase and glutathione S-transferases (GST-alpha, -mu, -pi) were assayed by immunoblotting. UDP-glucuronosyltransferase, beta-glucuronidase, sulfotransferase, sulfatase, GST activity, and glutathione (GSH) content, were determined by spectral assays. Results showed the absence of all probed cytochromes P-450 in normal lymphocytes and NHL cells tested. GST activity was significantly lower in chemoresistant NHL compared to normal lymphocytes. GST-alpha was not detected in either normal lymphocytes or NHL cells. GST-pi was the predominant isoenzyme, and GST-mu was not detected in chemosensitive NHL. GSH content was significantly lower in chemoresistant NHL compared to other lymphoid tissues tested. The conjugating enzymes UDP-glucuronosyltransferase and sulfatase were similar in either chemoresistant NHL compared to chemosensitive NHL. The activity of the hydrolytic enzyme beta-glucuronidase was lower in chemoresistant compared to chemosensitive NHL, whereas sulfatase was higher in sensitive NHL compared to normal lymphocytes. Epoxide hydrolase was not detected in either normal or NHL cells tested. In conclusion, these studies did not show any cytochrome P-450 in human lymphoid cells tested, but pointed out noteworthy differences for other enzyme systems tested.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1995

Prognostic value of c-mpl expression in myelodysplastic syndromes.

The c-mpl proto-oncogene which encodes a member of the hematopoietic cytokine receptor superfamily has been recently shown to be the receptor for thrombopoietin (TPO), which stimulates megakaryocyte progenitor expansion and differentiation. We studied c-mpl expression by Northern blot analysis, in a large series of 58 MDS. No expression was found in 14 patients with refractory anemia (RA) or with refractory anemia with ring sideroblasts (RARS). In contrast 11/26 (42%) patients with refractory anemia with excess of blasts (RAEB), or with RAEB in transformation (RAEBt), and 8/18 (44%) patients with chronic myelomonocytic leukemia (CMML) expressed c-mpl. In CMML patients, no correlation was found between c-mpl expression and any prognostic factor tested, nor with the course of the disease. In contrast, in RAEB and RAEBt, expression of c-mpl was correlated with high Bournemouth scoring (P < 0.005) and poor survival (P = 0.02) due to leukemic transformation. Forty-five per cent (5/11) of the c-mpl positive patients evolved towards AML with a mean follow-up of 10.5 months, while 13% (2/15) of the c-mpl negative patients developed a secondary leukemia, with a mean follow-up of 21.1 months. Moreover, in RAEB and RAEBt, a significant correlation was observed between c-mpl, CD34, megakaryocyte glycoprotein IIb (GPIIb) expression, and the presence of dysmegakaryopoiesis. These results indicate that patients with RAEB and RAEBt, with high expression of the c-mpl, CD34, and GPIIb genes, may identify a subgroup of patients with particularly poor prognosis, due to an increased risk of secondary leukemia. More aggressive therapy could be justified in these patients.

Antigens, CD↗
PubMed1995

Detection of malignant B cells in peripheral blood stem cell collections after chemotherapy in patients with multiple myeloma.

Autologous transplantation after high-dose chemo or radiotherapy is now frequently used for the treatment of patients with multiple myeloma (MM). The collection of peripheral blood stem cells (PBSC) has a theoretical advantage over autologous bone marrow collection as the malignant plasmacytic contamination is believed to be lower. However, the extent of B cell contamination in PBSC has not been extensively investigated. Using an immunoglobulin heavy chain gene 'fingerprinting' technique at diagnosis and during apheresis after one cycle of chemotherapy we detected a monoclonal population in 44% of PBSC samples (9 positives in 22 studied). There was no correlation between contamination and sex, age, Durie and Salmon classification, C-reactive protein and albumin. A significant correlation was observed with beta 2 microglobulin serum level (P = 0.02). Twenty one patients were grafted and up to the present, with a mean follow-up of 12 months, 6 patients have relapsed including 4 patients with contaminating B cells. Our results suggest that PBSC contamination, defines a 'poor risk' group of patients, with poor prognosis. However, we could not exclude reinitiation of the disease by plasmacyte stem cells after grafting.

Adult↗
PubMed1995

Expression of the Evi-1 gene in myelodysplastic syndromes.

Increased expression of the proto-oncogene Evi-1 has been shown to block the in vitro granulocytic differentiation of myeloid cells in response to granulocytic colony-stimulating factor and to interfere with the proliferation of erythroid cells in response to erythropoietin. We determined the frequency of Evi-1 expression in myelodysplastic syndromes (MDS), a disorder with altered proliferation and differentiation in the erythroid and myeloid lineages. Twenty-one patients were studied. Abnormal expression was found in 1/9 patients with refractory anemia and in 7/12 patients with refractory anemia with excess of blasts (RAEB) or in transformation (RAEBt). No correlation could be found between expression of Evi-1 and age, sex, hemoglobin level and percentage of bone marrow blasts or erythroblasts. This result suggests that the high incidence of Evi-1 expression which remains at low levels in RAEB and RAEBt is not a major determinant of ineffective erythropoiesis and myelopoiesis in MDS.

Base Sequence↗
PubMed1995

[Salvage therapy of relapsing or refractory malignant lymphoma with non-myelotoxic combined chemotherapy. Results of combination of cisplatin, bleomycin, methyl-GAG and prednisolone (Cis-BMP)].

Fifty-one patients with primary refractory or relapsed malignant lymphoma (47 non-Hodgkin's lymphoma and four Hodgkin's disease) were treated with a new chemotherapeutic regimen (cisplatinum, methyl GAG, bleomocyin, methyl prednisolon). Among these 51 patients, 41 had measurable disease. Three of these 41 patients achieved complete remissions (7.3%) and 17 showed partial response (41.5%). The low hematological toxicity of this chemotherapeutic combination allowed us to give the full dose at the planned cycle date in 90% of the cycles. No major toxicity were observed (two minor neurological toxicities, one ototoxicity associated with oral mucositis toxicity, 6 febrile episodes) during 164 courses. With a median follow-up of 12 months, 18% of patients were alive without disease. We conclude that in this particular population of malignant lymphomas, Cis-BMP is an effective therapy with minimal toxicity.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1994

Principal drug-metabolizing enzyme systems in L1210 leukemia sensitive or resistant to BCNU in vivo.

1,3-Bis(2-chloroethyl)-1-nitrosourea (BCNU) resistance has been mostly studied in vitro. In an attempt to better understand BCNU resistance in the in vivo situation, we compared the principal drug-metabolizing enzyme systems in two L1210 leukemia lines, one sensitive and one resistant to BCNU (L1210/BCNU), passaged in vivo in mice. The following enzymes were assayed by immunoblotting: cytochromes P-450 (1A1/1A2, 2B1/2B2, 2C8-10, 2E1, 3A), epoxide hydrolase (EH) and glutathione S-transferase (GST-alpha, -mu and -pi). The following enzymes and cofactors were assayed fluorometrically or spectrophotometrically: 1-chloro-2-4 dinitrobenzene-GST (CDNB-GST), total glutathione (GSH), UDP-glucuronosyltransferase, beta-glucuronidase, sulfatase and sulfotransferase. Results showed that cytochrome P-450 1A1/1A2 was the only isoenzyme detected in both L1210 and L1210/BCNU. CDNB-GST activity was significantly higher in L1210/BCNU compared with L1210. The isoenzyme GST-alpha was more abundant in L1210/BCNU compared with L1210, whereas GST-pi was expressed less in the BCNU-resistant leukemia line. GST-mu was not detected in either L1210 leukemia lines. GSH levels were similar in the two L1210 lines. No significant difference was observed between the two leukemia lines for the conjugative enzymes UDP-glucuronosyltransferase and sulfotransferase, whereas their corresponding hydrolytic enzymes beta-glucuronidase and sulfatase were about two-fold lower in the BCNU-resistant leukemia line. Epoxide hydrolase was 1.3-fold higher in L1210/BCNU compared with L1210 and this level was about three-fold higher than in mouse liver. In conclusion, these studies showed the presence of cytochrome P-450 1A1/1A2 in the two L1210 leukemia lines studied, and indicated noteworthy differences between the two leukemia lines for many enzyme systems such as GST, beta-glucuronidase, sulfatase and epoxide hydrolase. These data are of importance to better understand the mechanisms of drug resistance to nitrosoureas in vivo.

Animals↗
PubMed1994

[Treatment of mucositis with vitamin E during administration of neutropenic antineoplastic agents].

Mucositis represents one of the most frequent complications during chemotherapy or radiotherapy. Few studies have showed effective prevention against mucositis in this setting. In this randomized study, we tested the efficacy of vitamin E in the treatment of chemotherapy-induced mucositis. Twenty patients with malignant haemopathies were included; 19 patients were evaluable for the prevention of mucositis. Ten patients were treated with induction therapy for acute myelogenous leukaemia and 9 were treated with intensive therapy followed by autologous bone marrow transplantations. The severity of mucositis was evaluated according to World Health Organization classification. Our results showed that vitamin E may be of therapeutical value in the prevention of mucositis especially during induction therapy for acute myelogenous leukaemia.

Adolescent↗
PubMed1993

Expression of the c-mpl proto-oncogene in human hematologic malignancies.

Similar to two other hematopoietic growth factor receptors, the c-fms (macrophage colony-stimulating factor receptor) and the c-kit genes, c-mpl has been discovered through the study of oncogenic retroviruses. Unlike c-fms and c-kit, which both belong to a subgroup of tyrosine kinase receptors, the c-mpl proto-oncogene encodes a new member of the cytokine receptor superfamily. We have studied the expression of c-mpl in a series of 105 patients with hematologic malignancies using Northern blot analysis. The levels of c-mpl transcripts in lymphoid malignancies and in chronic myeloproliferative disorders were not significantly different from those found in normal bone marrow cells, in which c-mpl was barely detectable. In contrast, c-mpl expression was increased in 26 of 51 patients with acute myeloblastic leukemia (AML) and in 5 of 16 patients with myelodysplastic syndromes. Amplification of the c-mpl gene was detected in genomic DNA of one M4 AML patient. There was no significant correlation between c-mpl expression and the French-American-British classification of AML. Patients with high c-mpl expression appeared to belong to a subgroup of AML with a low rate of complete remission and a poor prognosis, including secondary leukemia and AML with unfavorable cytogenetic abnormalities.

Acute Disease↗
PubMed1993

Principal xenobiotic-metabolizing enzyme systems in human head and neck squamous cell carcinoma.

To better understand drug and carcinogen metabolism pathways in head and neck squamous cell carcinoma we assayed the principal drug- and carcinogen-metabolizing enzyme systems in both tumors and their corresponding adjacent non-tumoral tissues. Cytochromes P450 (1A1/A2, 2B1/B2, 2C8-10, 2E1, 3A4), epoxide hydrolase and glutathione S-transferases (GST-alpha, GST-mu, GST-pi) were assayed by immunoblotting. GST activity, total glutathione, UDP-glucuronosyltransferase, beta-glucuronidase, sulfotransferase and sulfatase, were determined by spectral assays. Results showed the absence of all probed cytochromes P450 in tumors and non-tumoral tissues, including P450 1A1/1A2 known to be involved in tobacco-related carcinogenesis. No statistical difference was noted between tumors and adjacent non-tumoral tissues for most enzymes studied (GST-alpha, GST-mu, GST-pi, GST activity, UDP-glucuronosyltransferase, beta-glucuronidase, sulfotransferase and sulfatase). However, total glutathione concentrations were significantly higher (P < 0.05) in tumors (47 +/- 20 nmol/mg protein) than in non-tumoral tissues (19 +/- 9). On the contrary, epoxide hydrolase was significantly less expressed in tumors (18 +/- 9 micrograms/mg protein) compared to corresponding non-tumoral tissues (37 +/- 9). These data provide new information concerning human head and neck cancer biology that could possibly have clinical implications.

Carcinoma, Squamous Cell↗
PubMed1993

Test dose-guided administration of cisplatin in an anephric patient: a case report.

BACKGROUND: Although cisplatin pharmacokinetics is well documented in patients with various degrees of renal dysfunction, no information is available concerning cisplatin administration to anephric patients. Since anephric patients may sometimes need cisplatin therapy, it is therefore of importance to define therapeutic guidelines for cisplatin administration in this patient population. PATIENT AND METHODS: Cisplatin was administered to an anephric patient (bilateral nephrectomy) requiring cisplatin therapy for a metastatic carcinoma of the urothelium. A test dose of 12 mg (7.5 mg/m2) of cisplatin was first administered as a 1 hour infusion in order to determine the patient's pharmacokinetic parameters. Filterable and total platinum levels were determined by flameless atomic absorption spectrophotometry. Haemodialysis was started 30 min before the beginning of the cisplatin infusion and was maintained for 4 h thereafter. RESULTS: Under haemodialysis, filterable and total platinum pharmacokinetics after the test dose were comparable with a patient with normal renal function, i.e. with peak plasma concentrations of 126 ng/ml and 166 ng/ml for the filterable and the total platinum, respectively. The area under the curves (AUC) were 154 ng.h/ml for the filterable and 11486 ng.h/ml for the total platinum. The terminal half-lives of filterable and total platinum were 0.42 h and 101 h, respectively. Based on the test dose platinum pharmacokinetics, a therapeutic dose of 100 mg (63 mg/m2) of cisplatin was administered. Following the therapeutic dose, peak plasma concentrations reached 1,120 ng/ml for the filterable and 1,280 ng/ml for the total platinum. The AUCs were 1,609 and 65,556 ng.h/ml for the filterable and the total platinum, respectively, as expected from the predicted AUCs obtained from the test dose pharmacokinetics. The terminal half-lives of filterable and total platinum were similar to the ones observed after the test dose, i.e. 0.36 h and 86 h, respectively. Although the patient died of rapidly progressive hepatic failure, the feasibility of the test dose-guided cisplatin administration in an anephric patient is demonstrated. CONCLUSION: This approach may be helpful in monitoring cisplatin therapy in similar cases requiring cisplatin administration.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1993

Prognostic factors of invasive pulmonary aspergillosis in leukemic patients.

The study objective was to identify prognostic factors associated with survival in patients treated for acute leukemias who developed invasive aspergillosis (IA) during induction therapy. This retrospective analysis involved 21 patients treated in two hematologic centers over a six-year period. All were treated in protective isolated rooms with high-dose amphotericin B as soon as fungal infection was suspected. Ten (45%) of the twenty-one patients died. There was no statistical difference between the patients who survived and those who died in relation to the mean time of onset of IA or the total and mean daily dose of amphotericin B. On the other hand a favourable outcome correlated strongly with complete leukemic remission (p < 0.0001): all but one of the patients with objective residual leukemia died of IA, whereas all those who achieved complete hematological remission survived. In conclusion, it seems that the main vital prognostic factor in these leukemic patients with IA was the achievement of complete remission. We were unable to control IA in 10 of 11 patients with refractory leukemia, regardless of neutropenic status, despite early administration of high-dose amphotericin B. All the patients who achieved complete remission were successfully treated with amphotericin B.

Acute Disease↗
PubMed1993

[Screening of principal enzymes involved in the metabolism of anticancer drugs in human and murine colonic tumors].

Since drug-metabolizing enzymes may influence the toxic response of tissues or organs to drugs, we studied their expression in human and colon tumor tissues, in an attempt to find new targets for chemotherapy and also to explain the intrinsic drug-insensitivity of most colon tumors to anticancer drugs. In the present work, we compared human colorectal tumors and peritumoral tissues to a mouse colorectal tumor (Co38) and normal murine colon with regard to their main drug-metabolizing enzyme systems. We investigated cytochromes P-450 (1A1/1A2, 2B1/B2, 2C, 2E1, 3A) and epoxide hydrolase (EH) by immunoblotting. Total glutathione (GSH) and the activities of the following enzymes: total GST, selenium-independent glutathione peroxidase (GPX), 1,2-dichloro-4-nitrobenzene-GST (DCNB-GST), ethacrynic acid-GST (EA-GST), UDP-glucuronosyltransferase 1 (UDPGT), beta-glucuronidase (beta G), sulfotransferase (ST) and sulfatase (S) were investigated by fluorometric and spectrophotometric assays. Results obtained by immunoblotting showed that mouse colon tumor Co38 did not express any of the probed cytochromes P-450, whereas human tumors showed the presence of cytochrome P-450 3A. EH was not expressed in either mouse colon tumor Co38 or normal mouse colon, whereas it was expressed in human peritumoral and tumoral colon tissues at similar levels. GPX and EA-GST were detected in all tumoral and non tumoral tissues of both species. DCNB-GST was expressed in all murine tissues investigated, but was not found in human tissues. For human peritumoral and tumoral colorectal tissues there was no significant difference between GST isoenzymes levels, whereas mouse colon tumor Co38 had a lower expression of DCNB-GST and EA-GST compared to normal mouse colon. No significant difference was observed between human tumors and peritumoral tissues for total GST, UDPGT1, beta G, ST and S activities. For murine colon tissues, the conjugation pathways (total GST, UDPGT1 and ST) were lower in Co38, whereas the opposite was observed for the hydrolytic enzymes (beta G and S). In conclusion, despite similarities between human and murine colon tumors, mouse colon tumor Co38 appears different from human colon tumors for many drug-metabolizing enzyme systems. These interspecies differences may have implications with regard to drug screening methodologies and preclinical evaluation of candidate anticancer drugs useful in the chemotherapy of human colorectal tumors.

Aged↗