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Biomedical subjects

S Castaigne

Publications and source records attributed to S Castaigne.

At least 73 records · Page 4Linked to original sources
PubMed1991

Pharmacokinetics of oral all-trans retinoic acid in patients with acute promyelocytic leukemia.

It has been shown that patients with acute promyelocytic leukemia (AML3 subtype) treated with all-trans retinoic acid (all-trans RA), 45 mg/m2/day, achieve complete remission through differentiation of the leukemic clone to mature myeloid cells, which die spontaneously. The pharmacokinetics of all-trans RA given by mouth were studied in 15 AML3 patients. Blood samples were drawn for 24 h following a single oral dose of 45 mg/m2 and assayed for all-trans RA and 13-cis retinoic acid (13-cis RA) plasma concentrations by specific high-performance liquid chromatography. In one patient all-trans RA and 13-cis RA levels were below the detection limits at all times. In the other patients, the time to peak concentration of all-trans RA was between 60 and 210 min (median 90 min) after ingestion, with maximum concentrations between 0.03 and 2.5 micrograms/ml (median 0.4 micrograms/ml). These concentrations were within the in vitro differentiating concentration range of all-trans RA for these patients' cells. In nine patients, enterohepatic cycling was suggested by the presence on the concentration versus time curve of a secondary peak that occurred at meal times. The apparent plasma elimination half-life was between 16.8 and 77.4 min (median 30 min). Detectable plasma levels of 13-cis RA in 12 patients indicated in vivo isomerization of all-trans RA. Despite the high inter-individual variability of all-trans RA pharmacokinetics in these patients, high blast cell counts and failure to respond to differentiation treatment tended to be associated with low all-trans RA Cmax values and high clearance estimates.

Administration, Oral↗
PubMed1991

[Biological parameters of the efficiency of retinoic acid in acute leukemia].

We have previously shown that all-trans retinoic acid therapy is an alternative therapy for acute promyelocytic leukemia (AML3) via differentiation of the leukemic cells. The t(15;17) translocation is specifically found in this leukemia. We and others have shown that through this translocation the RAR alpha gene is rearranged and its expression altered in AML3 cells. The gene is truncated and fused to a novel gene (PLM). This results in a fusion protein whose transactivating properties may be implicated in the leukemogenesis of this disease. Retinoic acid cytoplasmic binding proteins (CRABP and CRBP) are not detected by PAGE chromatography in normal or malignant hematopoietic cells. During all-trans RA therapy, a) all-trans RA plasma concentrations are within in vitro differentiating concentration (med. 0.4 microgram/ml); b) increased expression of the normal remaining RAR alpha allele is rapidly observed and may explain the paradoxical induction of RA differentiation in these cells; c) CRABPII is induced in the bone marrow cells of AML3 patients and remains detectable 1 month after withdrawal of RA. AML3 in relapse after RA therapy is always less sensitive to RA in vitro and in vivo. Our data suggest that modification of the metabolisation pathways of RA may be one of parameters linked to this resistance. It appears that the efficacy of all-trans RA is the resultant of multiple parameters (RA concentration, ratio of PML/RAR alpha transcripts to normal RAR alpha, CRABP) which need to be defined to efficiently monitor all-trans RA therapy in APL.

Drug Administration Schedule↗
PubMed1991

Treatment of promyelocytic blast crisis of chronic myelogenous leukemia with all trans-retinoic acid.

Two recent reports have described major clinical benefits from all-trans-retinoic acid (tRA) therapy of patients with promyelocytic leukemia (APL). This paper describes the first patient with a blast crisis of chronic myelogenous leukemia (CML-BC) who responded to oral tRA therapy. In vitro marrow studies, including clonogenic assays, immunopheno-typing, cytogenetics and premature chromosome condensation together with chromosome painting provided evidence for the in vivo differentiation and maturation of the malignant cells. The patient achieved a partial remission with reversal of all clinical features of disease, including normalization of peripheral blood counts, complete resolution of fever, fatigue and splenomegaly, and marked maturation of the bone marrow. This response to tRA in CML-BC is unique, and broadens the spectrum of diseases which may respond to retinoids.

Antineoplastic Agents↗
PubMed1990

All-trans retinoic acid as a differentiation therapy for acute promyelocytic leukemia. I. Clinical results.

Twenty-two patients with acute promyelocytic leukemia were treated with all-trans retinoic acid (RA, 45 mg/m2 per day) for 90 days. Of the 22, four patients were previously untreated, two were resistant after conventional chemotherapy, and 16 were in first (n = 11), second (n = 4), or third (n = 1) relapse. We observed 14 complete response, four transient responses, one failure, and three early deaths. Length of hospitalization and number of transfusions were notably reduced in complete responders. Correction of coagulation disorders and an increase of WBCs were the first signs of all-trans RA efficacy. Morphologic analysis performed at days 0, 15, 30, 45, 60, and 90 showed that complete remissions were obtained without bone marrow (BM) hypoplasia. Presence of Auer rods in the maturing cells confirmed the differentiation effect of the treatment. At remission, the t(15;17) initially present in 20 patients was not found. The in vitro studies showed a differentiation in the presence of all-trans RA in 16 of the 18 tested cases. The single nonresponder to all trans RA in vitro did not respond in vivo. Adverse effects of RA therapy--skin and mucosa dryness, hypertriglyceridemia, and increase of hepatic transaminases--were frequently noted. We also observed bone pain in 11 patients and hyperleukocytosis in four patients. Whether maintenance treatment consisted of low-dose chemotherapy or all-trans RA, early relapses were observed. Five patients are still in complete remission (CR) at 4 to 13 months. Our study confirms the major efficacy of all-trans RA in M3, even in relapsing patients. Remissions are obtained by a differentiation process.

Adult↗
PubMed1990

All-trans retinoic acid in acute promyelocytic leukemias. II. In vitro studies: structure-function relationship.

All-trans retinoic acid induces leukemic cells from patients with acute promyelocytic leukemia (M3) to differentiate in vitro to mature granulocytes which express the CD15 antigen and are capable of respiratory burst function. Of 35 M3 samples, only one failed to respond. In eight cases, we compared the efficacy of two naturally occurring isomers of retinoic acid, all-trans RA and 13-cis RA. Both isomers induce maximal differentiation at 10(-6) mol/L. The maximal response was maintained at 10(-7) mol/L for the all-trans but not for the 13-cis RA. We also observed that the metabolites 4-oxo-all-trans and 4-oxo-13-cis were effective at 10(-6) mol/L. This 1 order of magnitude difference in the in vitro differentiating potencies of all-trans RA and 13-cis RA in the blasts of promyelocytic leukemias predicts a difference in the clinical efficacy of the two drugs.

Cell Transformation, Neoplastic↗
PubMed1990

Low-dose cytarabine versus intensive chemotherapy in the treatment of acute nonlymphocytic leukemia in the elderly.

We conducted a randomized multicenter trial comparing low-dose cytarabine (LD ARA-C) (20 mg/m2 for 21 days) with an intensive chemotherapy (rubidazone [a daunorubicin-derived agent], 100 mg/m2 for 4 days, ARA-C 200 mg/m2 for 7 days) in 87 patients over 65 years of age with de novo acute nonlymphocytic leukemia (ANLL). Forty-one patients received LD ARA-C and 46 received intensive chemotherapy. The number of complete remissions (CRs) but also of early deaths was higher in the intensive chemotherapy group, while partial remissions (PRs) and failures were more frequent in the LD ARA-C group (P less than .001). Infectious complications during induction treatment were more numerous and more severe in the intensive chemotherapy group (P less than .01). Patients treated with LD ARA-C required fewer RBC transfusions (P less than .02), fewer platelet transfusions (P less than .01), and had a shorter hospital stay for induction treatment (P less than .01). Overall survival and CR duration were not significantly different in either group. In the LD ARA-C group, the survival of patients with PR and those of patients in CRs was identical. We conclude that in a selected group of elderly patients with de novo ANLL a higher number of CRs may be obtained with intensive chemotherapy, but that with LD ARA-C, the number of early deaths is lower, and long-lasting PRs are obtained, resulting in a similar overall survival.

Aged↗
PubMed1990

Prognostic factors of acute non lymphoblastic leukemia in children and adults. Results from two multicentric trials (705 patients).

705 children and adults patients with de novo acute nonlymphoblastic leukemia were entered from 1981 to 1989 into 2 prospectives multicenter trials: 01AM81 and 01AM86. They received an intensive induction course with Rubidazone 200 mg/sqm/day x 4 days and cytosine arabinoside 200 mg/sqm/day x 7 days, then 3 consolidation courses at outpatients, and a maintenance treatment. Total duration of therapy was 3 years. The overall complete remission rate was 80%. The median overall survival time was 19 months and the 5-year survival rate is 26%. The median remission duration for the 568 remitters was 18 months and the 5-year first remission rate is 30%. Prognostic factors for the remission rate were age, initial leukocytosis, FAB subtype. Prognostic factors for remission duration were the delay until CR, initial leukocytosis and karyotype.

Adolescent↗
PubMed1990

The retinoic acid receptor alpha gene is rearranged in retinoic acid-sensitive promyelocytic leukemias.

All-trans retinoic acid (RA), the active metabolite of vitamin A, has recently been demonstrated to be an efficient alternative to chemotherapy in the treatment of acute promyelocytic leukemia (M3 subtype of the French-American-British cytological classification). Complete remission is obtained by inducing terminal granulocytic differentiation of the leukemic cells. To elucidate whether the effect of retinoic acid on the differentiation of M3 leukemic cells was related to any specific characteristics of its receptor, we analyzed the structure and expression of retinoic acid receptor (RAR) genes in 16 M3 patients. Abnormal RAR alpha transcripts were detected in 13 cases. In nine patients, the genomic DNA was analyzed by Southern blotting and evidence for a rearranged RAR alpha gene was found generated in four cases. Normal RAR transcripts and germline restriction fragments were found in samples from normal or other leukemic cells, suggesting that this alteration of the RAR alpha gene is specifically seen in M3 leukemias. These results suggest that alteration of the retinoic acid receptor alpha may be implicated in M3 leukemogenesis.

Adult↗
PubMed1990

In vitro effects of retinoic acid.

Retinoids, synthetic and natural analogues of vitamin A, play fundamental roles both in directing the spatial organization of cells during the development of vertebrate limbs and in the maintenance of growth and differentiation of many adult tissues. They also block the phenotypic expression of cancer in vitro; inhibit growth and induce differentiation in many animal and human malignant cell types. They have proved beneficial in skin diseases, cancer prevention and in acute promyelocytic leukemia.

Animals↗
PubMed1990

Retinoic acids in the treatment of acute promyelocytic leukemia.

Retinoic acid, the active metabolite of vitamin A has been shown to differentiate in vitro human leukaemic cells from patients with acute promyeolocytic leukaemia (APL). The results obtained in vivo with the 13-cis isomer of retinoic acid in combination with or after chemotherapy in four cases of APL are described. More recently Huang et al from the Shangai Institute of Haematology have treated 24 cases of APL with all-trans retinoic acid alone. They obtained 24 complete remissions. This success prompted us to treat patients with APL and a contra-indication to chemotherapy with all-trans retinoic acid. The results confirm the great efficacy of all-trans retinoic acid in APL.

Aged↗
PubMed1989

alpha-IFN treatment does not induce Ki-ras expression in hairy-cell leukemia patients.

alpha-Interferon (IFN) is effective in the treatment of hairy-cell leukemia (HCL), but the treatment is sometimes over a long period. Biological changes such as the increase of tumorigenicity can occur rapidly in vivo as a result of beginning this treatment; an increase in c-Ki-ras oncogene expression has also been observed. In order to determine whether the findings observed in vitro would be duplicated in an in vivo system, we decided to analyze the Ki-ras RNA and protein levels in the lymphocytes of three HCL patients, compared with these levels in seven normal donors and one non-treated HCL patients. Ki-ras was not activated by IFN, at least not in lymphocytes. Therefore, the data suggest that the drug could be used for long-term therapy with relatively low risk to the patients.

Gene Expression Regulation↗
PubMed1989

Human CD3 gamma delta + activated lymphocytes exhibit killer activity in vitro against autologous leukemic cells.

TCR gamma delta expressing T cell clones are able to exhibit in vitro strong cytolytic activity against cultured tumor cell lines as the myeloid K562 or the Burkitt's lymphoma Daudi cell line. We investigate the possibility of developing TCR gamma delta bearing T cell lines from peripheral blood of 2 leukemic patients in complete remission in order to study their ability to kill autologous leukemic cells. T lymphocyte clones are obtained by limiting dilution of lymphocytes from the blood of patients with an acute lymphoblastic leukemia (ALL). The T cell clones are first selected for their CD8- CD4-phenotype and then for their ability to react with the monoclonal antibody anti-CD3 without presenting reactivity with a monoclonal antibody directed against the TCR alpha beta. Further biochemical studies have indicated that the CD3 associated structure expressed on the cell membrane of these T cell clones is a gamma delta heterodimer. Functional analysis have indicated that these cloned cells are able to kill in a classical cell mediated lysis assay the autologous leukemic cells only when also LAK activity is observed. Thanks to this clonal expansion 10(10) cells/week indefinitely only 1 sample of peripheral blood will be necessary. Would these results be found with other leukemic patients, we propose to use this procedure for a possible application of killer cells for maintenance therapy of leukemia.

Antigens, Differentiation, T-Lymphocyte↗
PubMed1989

Treatment of aggressive multiple myeloma by high-dose chemotherapy and total body irradiation followed by blood stem cells autologous graft.

Eight patients with stage III aggressive multiple myeloma, refractory to current chemotherapy in six cases, were treated by high-dose chemotherapy (nitrosourea, etoposide, and melphalan) (HDC) and total body irradiation (TBI), followed by autografting with blood stem cells. These cells were previously collected by leukapheresis performed during hematologic recovery following cytotoxic drug-induced bone marrow aplasia. Seven patients were alive 9 to 17 months after HDC-TBI and graft. One died at day 40 from cerebral bleeding. All living patients achieved a 90% or greater reduction in tumor mass. In two cases, a complete remission (CR) has persisted at a follow-up of 15 and 16 months. Three patients have been well and off therapy with stable minimal residual disease (RD) since 10, 11, and 17 months, respectively. A patient in apparent CR and another with RD have relapsed 9 to 12 months posttreatment. Autologous blood-derived hematopoietic stem cells induced successful and sustained engraftment in all living patients. These results, although still preliminary, indicate that HDC and TBI, followed by blood stem cells autograft, which has both practical and theoretical interest over allogeneic or autologous bone marrow transplantation, deserve consideration in selected patients with multiple myeloma.

Adult↗
PubMed1989

Treatment of multiple myeloma by high dose chemotherapy, total body irradiation and autologous blood stem cell autograft.

Fourteen patients with stage III aggressive multiple myeloma were treated by high dose chemotherapy (carmustine, etoposide and melphalan) and total body irradiation. This procedure was followed by autografting using blood stem cells previously collected by leukapheresis performed during recovery of cytotoxic drug-induced bone marrow aplasia. One patient died from cerebral bleeding at day 40. All other patients, including 9 whose disease was refractory to conventional treatments, achieved an impressive tumor mass reduction (over 90% in 12 cases). Two patients relapsed and died 12 and 15 months after the graft; another one relapsed but is still alive at 24 months. Two to 23 months (median 12 months) after the autograft, 10 patients are well either in apparent complete remission (2 cases) or with a state of stable minimal residual disease. Autologous blood-derived hematopoietic stem cells induced successful and sustained engraftment in the 13 evaluable patients. The cells collected by leukapheresis were studied for clonal Ig genes rearrangements indicative of circulating tumoral cells (or clonal B precursors) and none were found. Although preliminary, these results appear promising and high dose chemotherapy followed by autologous blood stem cell graft deserves consideration in young patients with multiple myeloma.

Adult↗
PubMed1989

Hairy cell leukemia: follow-up after completion of alpha interferon treatment.

Between May 84 and December 85, 61 patients were treated for hairy cell leukemia by (recombinant or natural) alpha-IFN in a single institution. The responses obtained after 7 or 12 months of treatment are presented and the follow-up of the 39 patients for whom the treatment had been stopped for more than 12 months is evaluated. Neither clinical or histological parameters at presentation nor the type of timing of the interferon used allowed to predict the quality of response. The median time-lapse before the occurrence of neutropenia below 1.10(9)/l in patients with normal blood counts at the end of treatment was 12 months. However early relapses after the treatment stop were observed more frequently in patients with initially severe neutropenia or hyperleucocytosis. The therapeutic strategy in hairy cell leukemia is discussed.

Female↗