Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026986 (myelodysplastic syndrome)
 14,926 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

P39/Tsugane is a myelomonocytoid cell line derived from a patient with myelodysplastic syndrome (MDS). The cells readily undergo apoptosis in response to various agents, and the cell line has been suggested as a useful model to study apoptosis in MDS. The aims of the present study were to assess differentiation and apoptosis induced with all-trans retinoic acid (ATRA) and etoposide, to characterize the mode of apoptosis in these two model systems, and to assess the influence of granulocyte colony-stimulating factor (G-CSF), which in combination with erythropoietin has been shown to inhibit apoptosis in MDS. ATRA induced differentiation and apoptosis in a concentration- and time-dependent manner. Differentiated cells were partially rescued (by 50%) from apoptosis with G-CSF. Etoposide induced apoptosis in a concentration- and time-dependent manner, but no signs of preceding maturation or G-CSF rescue were detected. ATRA- and etoposide-induced apoptosis were both mediated through the caspase pathway and were partially blocked with the general caspase inhibitor zVAD-fmk. Simultaneous treatment with G-CSF and zVAD-fmk additively blocked ATRA-induced apoptosis. However, the two pathways differed in terms of substrate cleavage during apoptosis. ATRA-induced apoptosis caused actin cleavage, which was not affected by G-CSF, and Bcl-2 downregulation. Etoposide induced a caspase-dependent cleavage of Bcl-2, while actin remained intact. The Fas system did not seem to play a major role in any of these apoptotic pathways. Our results may provide new tools to study the mechanisms of apoptosis in MDS.
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PMID:Two pathways of apoptosis induced with all-trans retinoic acid and etoposide in the myeloid cell line P39. 1042 9

Thirty patients with high-risk myelodysplastic syndrome, defined as > 5% bone marrow blasts, were treated with a combination of oral all-trans-retinoic acid (45 mg/m2 daily) and subcutaneous AraC (10 mg/m2) on days 1-14 of each 28-35 day cycle repeated for 2-6 cycles. Complete remission lasting 9, 12, and 15 months was achieved in three patients. Partial and minor response did not translate into meaningful clinical improvement, like complete responders. Overall incidence of leukemia transformation and survival of this cohort of patients was no different from the expected outcome for a group of patients with similar characteristics.
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PMID:Treatment of unfavorable myelodysplastic syndrome with all-trans-retinoic acid and subcutaneous Ara C. 1047 20

We evaluated the in vitro effect on clonogenic potential (CFU-GM) and apoptosis in myelodysplastic syndromes (MDS) progenitors of an anti-oxidant (N-acetylcysteine, NAC) and/or a differentiating (all-trans retinoic acid, ATRA) agent. NAC significantly reduced apoptosis, both NAC and ATRA induced an increase in CFU-GM, but NAC seemed to be particularly effective in the high risk (HR) MDS. NAC + ATRA conferred a significant advantage in terms of CFU-GM with respect to NAC and ATRA alone. Tumor Necrosis Factor-alpha (TNF-alpha) levels decreased after incubation with NAC in the MDS samples. This study shows that ineffective hemopoiesis in MDS could benefit from both NAC and ATRA, suggesting that anti-oxidant treatment may play a role in guaranteeing MDS cell survival, predisposing them towards differentiation.
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PMID:Efficacy of N-acetylcysteine and all-trans retinoic acid in restoring in vitro effective hemopoiesis in myelodysplastic syndromes. 1065 49

AML with trilineage myelodysplasia (AML/TMDS) is recognized as having of poor prognosis due to its resistance to chemotherapy in comparison with de novo AML. An AML/TMDS patient who failed to respond to ordinary induction therapy achieved complete remission with combination therapy consisting of all-trans retinoic acid (ATRA) and low-dose Ara-C. No serious toxicity was observed. ATRA combined with low-dose Ara-C could be an alternative treatment for this kind of patient.
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PMID:[All-trans retinoic acid combined with low-dose cytosine arabinoside treatment for acute myelogenous leukemia with trilineage myelodysplasia--a case report]. 1126 15

The translocation t(11;16)(q23;p13) has only been documented in patients with acute leukemia or myelodysplasia secondary to therapy with drugs targeting DNA topoisomerase II. We have established a myeloid cell line (SN-1) with the MLL-CBP fusion gene from an acute leukemia patient with t(11;16)(q23;p13). Although SN-1 cells were not induced to differentiate by all-trans retinoic acid (ATRA) and 1alpha,25-dihydroxyvitamin D(3) (VD3), retinoid X receptor (RXR) agonists, such as 9-cis retinoic acid and Ro48-2250, effectively induced differentiation of the cells. Downregulation of the expression of the MLL-CBP fusion gene occurred during the differentiation of SN-1 cells. When SN-1 cells were treated with MLL-CBP antisense oligonucleotide, the cells were induced to differentiate by ATRA or VD3, suggesting that the MLL-CBP fusion gene dominant-negatively suppresses ATRA- or VD3-induced differentiation. Moreover, suboptimal concentrations of sodium butyrate, a histone deacetylase inhibitor, had a cooperative effect with ATRA or VD3 in inducing the differentiation of SN-1 cells. The downregulation of the expression of MLL-CBP mRNA was accompanied by the induction of differentiation. These findings suggest that RXR agonists or a clinically applicable combination of ATRA and butyrate derivatives might be useful for differentiation therapy in leukemia patients with the MLL-CBP fusion gene.
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PMID:Downregulation of MLL-CBP fusion gene expression is associated with differentiation of SN-1 cells with t(11;16)(q23;p13). 1131 67

Vasculitis may accompany neoplasias and be of paraneoplastic type or associated with drugs used in patient treatment. We evaluated skin biopsies of twenty-eight cases with vasculitis accompanying leukemias reviewed and clinical outcome was evaluated. Eleven of the 28 cases had paraneoplastic vasculitis and 17 had vasculitis associated with various drugs including chemotherapy, cytokines and antibacterial agents. Paraneoplastic vasculitis was seen in 3 cases with chronic myelocytic leukemia in blastic phase, 5 patients with acute myeloblastic leukemia, and 3 with myelodysplastic syndrome. Drugs responsible for the 17 cases of vasculitis included hydroxyurea, vincristine, cytosine-arabinoside, methotrexate, all-trans retinoic acid, granulocyte-colony stimulating factor, interferon and antibiotics. Paraneoplastic vasculitis is not rare in leukemias and may be a manifestation of the blastic phase of chronic myeloid leukemia. Furthermore paraneoplastic vasculitis can be fatal in myelodysplastic syndromes and may be present clinically before the specific diagnosis is made. Drugs used in routine therapy may be the cause of the vasculitis, thus skin biopsy should be performed in all cutaneous lesions in patients with hemopoietic neoplasias.
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PMID:Vasculitis and leukemia. 1142 10

Seventeen cases of acute promyelocytic leukemia (APL) treated with all-trans-retinoic acid (ATRA) and combination chemotherapy at Tokyo Metropolitan Komagome Hospital between 1992 and 1999 were reviewed, and divided into 2 karyotype-based cytogenetic groups. One group comprised 7 patients with either the typical t(15;17) alone or a normal karyotype, and the other group comprised 10 patients with additional karyotypic abnormalities. No patient had received prior chemotherapy or irradiation, and no cases were complicated by a history of myelodysplastic syndrome before the diagnosis of APL. There were no significant differences in clinical characteristics at disease presentation. Complete remission was achieved in all 17 patients and karyotypes of bone marrow cells normalized in all cases. No differences were found in relapse rate, overall survival, or disease-free survival between the 2 groups. The analysis did not reveal any significant effect of additional chromosomal abnormalities on the prognosis of APL patients undergoing treatment with ATRA. However, a small number of patients were assessed in this study, and further cumulative studies are needed.
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PMID:Effect of additional chromosomal abnormalities in acute promyelocytic leukemia treated with all-trans-retinoic acid: a report of 17 patients. 1150 65

The use of all-trans retinoic acid (ATRA) in combination with chemotherapy has markedly improved the prognosis for patients with acute promyelocytic leukemia (APL); the higher complete remission (CR) and survival rates now reported in this disease almost approach those obtained for other highly curable hematologic malignancies. Of 77 patients with APL who were consecutively treated at a single institution and who achieved CR after induction and consolidation therapy, 5 (6.5%) acquired therapy-related myelodysplasia (tMDS), acute myelogenous leukemia (AML), or both (tMDS-AML). Of these, 3 of 46 (6.5%) patients received front-line chemotherapy with or without ATRA and acquired tMDS-AML while in first remission of APL. Two underwent repeated chemotherapy cycles with ATRA because of APL relapse and acquired tMDS-AML while in the second or third remission of APL. In 2 patients, clinical and biologic characteristics of tMDS-AML were as expected for postalkylating forms (long latency, MDS phase preceding AML, karyotypic aberrations involving chromosomes 5 or 7), even though one of them had not previously received alkylating drugs. Three of the 5 patients died shortly after tMDS-AML diagnosis, one is alive with tMDS, and one is alive and in CR after allogeneic bone marrow transplantation. The occurrence of tMDS-AML after successful therapy for APL is an emerging problem. The availability of prognostic score systems at initial diagnosis and monitoring of residual disease by polymerase chain reaction might allow better tailoring of treatment intensity in APL to spare unnecessary toxicity and to minimize the risk for tMDS-AML in patients who are presumably cured.
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PMID:Therapy-related myelodysplastic syndrome-acute myelogenous leukemia in patients treated for acute promyelocytic leukemia: an emerging problem. 1221 Nov 97

In vitro studies suggest that all-trans retinoic acid (ATRA) synergizes with erythropoietin (EPO) for the stimulation of hematopoiesis in patients with myelodysplastic syndrome (MDS). A clinical trial was performed to evaluate whether a combination of these agents was effective in relieving the cytopenias associated with MDS. Twenty-seven patients with low- or intermediate-risk MDS were enrolled in a 12-week study. ATRA was administered orally at the dose of 80 mg/m(2) per day in 2 divided doses for 7 consecutive days every other week. Recombinant human EPO was given subcutaneously 3 times a week. The EPO dose was initiated at 150 U/kg and was increased to 300 U/kg if after 6 weeks there was no or there was suboptimal erythroid response. Patients who responded to therapy were continued on ATRA and EPO at the same doses for 6 additional months (extension phase). Further treatment was given to patients with a continued response. Clinically significant erythroid responses with increases of hemoglobin levels of at least 1 g/dL or reduction of transfusion needs were seen in 13 (48%) patients, with 4 showing improved responses after dose escalation of EPO. Ten (37%) patients displayed continued responses during 6 months of extended treatment, and 7 (26%) are still responsive after a follow-up period of 13 months. Neutrophil responses were observed in 5 of 12 patients with neutropenia, and platelet responses were observed in 6 of 9 patients with thrombocytopenia. Three patients displayed trilineage responses that were sustained during continuation therapy. Side effects were observed in all patients but were of mild entity and did not require discontinuation of therapy. It is concluded that the combination ATRA + EPO is an effective and well-tolerated treatment for patients with low- and intermediate-risk MDS. The optimal ATRA and EPO schedule and the role of maintenance treatment remain to be determined and warrant further investigation.
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PMID:Sustained response to recombinant human erythropoietin and intermittent all-trans retinoic acid in patients with myelodysplastic syndromes. 1186 Dec 71

Two acute promyelocytic leukaemia patients, treated with all-trans retinoic acid and combination chemotherapy, acquired a deletion of 11q within 12 months of diagnosis. One patient died in relapse, with both t(15;17) and del(11q) cell lines co-existing. Patient 2 remains in remission with del(11q) in 70% metaphases, despite normal marrow morphology. No deletion of the MLL gene was identified in the latter patient. The early appearance of a del(11q) is unusual, particularly without morphological evidence of myelodysplasia. We hypothesize that the del(11q) was therapy-induced but the absence of other genetic lesions has resulted in no accompanying morphological changes.
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PMID:Appearance of del(11q) in two patients with acute promyelocytic leukaemia treated with all-trans retinoic acid and combination chemotherapy. 1210 Jan 54


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