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)

Valproic acid (VPA) inhibits histone deacetylase activity and induces differentiation of acute myeloid leukemia (AML) blasts in vitro. We observed clinical responses to VPA in patients with myelodysplastic syndrome (MDS) and AML. Here, we report follow-up data on 75 patients. Of these, 66 were started on VPA monotherapy, with later addition of all-trans retinoic acid (ATRA) in patients who did not respond or relapsed. Nine patients were treated with VPA + ATRA from the start. Median treatment duration was 4 months for VPA and 2 months for ATRA. Hematological improvement, according to international working group criteria for MDS, was observed in 18 patients (24%). Median response duration was 4 months. ATRA exerted no additional effect in patients receiving the combination from the start or benefited primary VPA nonresponders. However, of ten VPA responders who relapsed, four achieved a second response after addition of ATRA. Response rates were strongly dependent on disease type according to WHO classification. We found a response rate of 52% in MDS patients with a normal blast count (refractory sideroblastic anemia, refractory cytopenia with multilineage dysplasia, and refractory sideroblastic cytopenia with multilineage dysplasia). The response rate was 6% in refractory anemia with excess blasts (I + II), 16% in AML, and 0% in chronic myelomonocytic leukemia. Bone marrow blast count was the only variable that predicted responses. We conclude that VPA is clinically useful in low-risk MDS. For patients with high-risk MDS, VPA may be combined with chemotherapy or demethylating drugs. If patients relapse after an initial response to VPA, ATRA has the potential to induce a prolonged second response.
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PMID:Results of a phase 2 study of valproic acid alone or in combination with all-trans retinoic acid in 75 patients with myelodysplastic syndrome and relapsed or refractory acute myeloid leukemia. 1627 Feb 13

This study was aimed to examine whether a combination of all-trans retinoic acid (ATRA), 1, 25-dihydroxyvitamin D(3) and androgen possesses the therapeutic value for the MDS-refractory anemia (MDS-RA), and to analyze the mechanisms in detail. 62 cases receiving a scheme of combination of ATRA, 1, 25-dihydroxyvitamin D(3) and androgen (group A) were monitored. The remaining 33 cases (group B) were provided with vitamin supplementation, chalybeate drugs, and one or two of the combination. Bone marrow aspiration and biopsy were performed for collecting the specimens at the baseline and afterwards. The conditions of the patients were monitored by means of weekly complete blood counts and the monthly examination, including toxicity test, physical examination, electrocardiography, and biochemistry panel. The results showed that after treating for 8 weeks in group A, 4 out of 62 patients showed complete remission and 12 patients showed partial remission according to the defined response criteria, and 43 patients (69.35%) showed hematological improvement (HI). The further treatment for 16 out of 62 patients (25.81%), 13 failures (10 deaths, 2 RAEB and 1 RAEB-T) and 3 transformations (M(2), M(3), M(5)) with a median survival interval of 26.25 months, were observed and interrupted for some reasons. However, partial remission was observed only in 3 patients in group B, and HI amounted to 51.51%. Furthermore, the disease progression was observed in 12 out of 33 patients (36.36%) with a median survival interval of 16 months, 9 failures (including 6 deaths, 2 RAEB and 1 RAEB-T) and 3 transformations (M(2), M(3), M(4)). The overall ratios of survival for 3 and 5 years in group A, which received the combination, reached to 69.24% and 53.72% respectively, in comparison with 52.23% and 31.34% in the patients of group B (log-rank, P = 0.016). The following requirements, if were met, would be significant for prognosis: the combination regiment, no transformation, children, no complication, female, 90-120 g/L of hemoglobin concentration, normal cellular bone marrow and uni-cytopenias (P < 0.05). Moreover, Cox regression showed that therapy, transformation and age are all the independent factors (P < 0.05). It is concluded that the combination of above mentioned 3 drugs may be effective and safe treatment for the patients with MDS-RA. Its relevant mechanisms can be involved in the combination, that elicits a wide range of pharmacological effects, such as differentiation, anti-tumor-promotion, anti-apoptosis, anti-angiogenesis, anti-cachexia and immunoregulation.
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PMID:[Retrospective observation of curative effects on MDS refractory anemia with combination of all-trans retinoic acid, 1, 25-dihydroxyvitamin D3 and androgen]. 1627 59

Several new therapeutic strategies are now considered for acute myelogenous leukaemia (AML), including modulation of protein lysine acetylation through inhibition of histone deacetylases (HDACs): a large group of enzymes that alters the acetylation and, thereby, the function of a wide range of nuclear and cytoplasmic proteins. Firstly, HDACs can deacetylate histones as well as transcription factors, and can modulate gene expression through both these mechanisms. Secondly, acetylation is an important post-translational modulation of several proteins involved in the regulation of cell proliferation, differentiation and apoptosis (e.g., p53, tubulin, heat-shock protein 90). The only HDAC inhibitors that have been investigated in clinical studies of AML are butyrate derivatives, valproic acid and depsipeptide. In the first studies, the drugs have usually been used as continuous therapy for several weeks or months, and in most studies the drugs were used alone or in combination with all-trans retinoic acid for treatment of patients with relapsed or primary resistant AML. Neurological toxicity and gastrointestinal side effects seem to be common for all three drugs. Complete haematological remission lasting for several months has been reported for a few patients (< 5% of included patients), whereas increased peripheral blood platelet counts seem more common and have been described both for patients with AML and myelodysplastic syndromes. Taken together, these studies suggest that HDAC inhibition can mediate antileukaemic effects in AML, but for most patients the clinical benefit seems limited and further studies of combination therapy are required.
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PMID:Protein lysine acetylation in normal and leukaemic haematopoiesis: HDACs as possible therapeutic targets in adult AML. 1644 Dec 28

Epigenetic alterations of chromatin due to aberrant histone deacetylase (HDAC) activity and transcriptional silencing of all-trans retinoic acid (ATRA) pathway are events linked to the pathogenesis of acute myeloid leukemia (AML) that can be targeted by specific treatments. A pilot study was carried out in eight refractory or high-risk AML patients not eligible for intensive therapy to assess the biological and therapeutic activities of the HDAC inhibitor valproic acid (VPA) used to remodel chromatin, followed by the addition of ATRA, to activate gene transcription and differentiation in leukemic cells. Hyperacetylation of histones H3 and H4 was detectable at therapeutic VPA serum levels (>or=50 microg/mL) in blood mononuclear cells from seven of eight patients. This correlated with myelomonocytic differentiation of leukemic cells as revealed by morphologic, cytochemical, immunophenotypic, and gene expression analyses. Differentiation of the leukemic clone was proven by fluorescence in situ hybridization analysis showing the cytogenetic lesion +8 or 7q- in differentiating cells. Hematologic improvement, according to established criteria for myelodysplastic syndromes, was observed in two cases. Stable disease and disease progression were observed in five and one cases, respectively. In conclusion, VPA-ATRA treatment is well tolerated and induces phenotypic changes of AML blasts through chromatin remodeling. Further studies are needed to evaluate whether VPA-ATRA treatment by reprogramming differentiation of the leukemic clone might improve the response to chemotherapy in leukemia patients.
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PMID:Sequential valproic acid/all-trans retinoic acid treatment reprograms differentiation in refractory and high-risk acute myeloid leukemia. 1695 Dec 8

The combination of a DNA hypomethylating agent with a histone deacetylase inhibitor has synergistic antileukemia activity and may restore sensitivity to all-trans retinoic acid (ATRA). We conducted a phase 1/2 study of the combination of 5-azacitidine (5-AZA), valproic acid (VPA), and ATRA in patients with acute myeloid leukemia or high-risk myelodysplastic syndrome. 5-AZA was administered subcutaneously at a fixed dose of 75 mg/m(2) daily for 7 days. VPA was dose-escalated and given orally daily for 7 days concomitantly with 5-AZA. ATRA was given at 45 mg/m(2) orally daily for 5 days, starting on day 3. A total of 53 patients were treated. Their median age was 69 years (range, 5-84 years). The maximum tolerated dose of VPA in this combination was 50 mg/kg daily for 7 days. Dose-limiting toxicity was reversible neurotoxicity. The overall response rate was 42%. In previously untreated older patients, the response rate was 52%. Median number of courses to response was 1 (range, 1-3 courses). Median remission duration was 26 weeks, and median survival has not been reached. A significant decrease in global DNA methylation and induction of histone acetylation were achieved. VPA blood levels were higher in responders (P < .005). In conclusion, the combination studied is safe and has significant clinical activity. This clinical trial was registered at www.clinicaltrials.gov as no. NCT00326170.
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PMID:Safety and clinical activity of the combination of 5-azacytidine, valproic acid, and all-trans retinoic acid in acute myeloid leukemia and myelodysplastic syndrome. 1759 41

Valproic acid (VPA) has been used as an anticonvulsant for decades. Recently, it was demonstrated that VPA also acts as a histone deacetylase inhibitor and induces differentiation and apoptosis in a variety of malignant cells in vitro. The effect of VPA on tumor cells differs according to cell type, degree of differentiation, and underlying genetic alterations. Clinical trials with VPA have focused on acute myeloid leukemia and the myelodysplastic syndromes. When it was used as monotherapy or in combination with all-trans retinoic acid, which synergizes in vitro, VPA achieved hematologic improvement in a subset of patients. Similar to other inhibitors of histone deacetylases, complete or partial remissions rarely were observed. In this report, the authors reviewed the in vitro and in vivo data obtained with VPA, and they considered possible combination regimens aimed at improving therapeutic efficacy.
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PMID:Valproic acid for the treatment of myeloid malignancies. 1834 2

Treatment of acute promyelocytic leukemia (APL) with a combination of anthracycline-based chemotherapy and all-trans retinoic acid (ATRA) leads to very high rates of complete remission and survival. There are only a limited number of publications on the development of therapy-related myelodysplastic syndrome (MDS) or acute myeloid leukemia during follow-up of APL. Although drugs targeting at DNA-topoisomerase II characteristically induce translocations involving 11q23, this was seldom seen in patients treated for APL. We report on a patient initially diagnosed with APL. Response to therapy was monitored by fluorescence in situ hybridization (FISH) and reverse-transcriptase polymerase chain reaction for the PML-RARalpha rearrangement. Consecutive samples showed a swift and complete reduction of PML-RARalpha rearranged cells. Twenty months after diagnosis, however, conventional cytogenetics revealed a complex karyotype with a translocation involving 11q23 and loss of chromosomes 7q and Xq. FISH analysis with the MLL probe identified 2q37 (harboring the SEPT2 gene) as the translocation partner of chromosome 11. We consider the rather unique t(2;11)(q37;q23) as the primary event causing therapy-related MDS in our patient. This case stresses the importance of conventional karyotyping to be performed on a regular basis in all treated APL patients for the early detection of chromosomal aberrations that indicate the development of therapy-related MDS or acute myeloid leukemia.
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PMID:Translocation (2;11)(q37;q23) in therapy-related myelodysplastic syndrome after treatment for acute promyelocytic leukemia. 1820 42

Hypomethylating agents, such as 5-azacitidine (5-AZA) and 5-aza-2'-deoxycytidine (decitabine), have recently been approved for the treatment of myelodysplastic syndromes (MDS). Several randomized trials have shown favorable results concerning response rate, survival, transformation to acute leukemia, and quality of life. In these trials, treatment was administered continuously until progression. In the retrospective study presented here, we evaluated the outcome of patients with higher risk MDS or secondary acute myeloid leukemia (sAML) treated with a limited number of 5-AZA cycles. A total of 32 patients received 5-AZA alone (n=30) or in combination with valproic acid and all-trans retinoic acid (n=2). 5-AZA was administered subcutaneously at a fixed dose of 75 mg/m(2) daily for 7 days and repeated every 28 days. 5-AZA was given for a median of four courses. Treatment was continued for two more cycles as consolidation in patients who had achieved complete remission (CR), marrow CR, or stable disease with hematologic improvement. The overall response rate was 50% according to the modified International Working Group criteria. Complete remissions were achieved in 15.6% and stable disease in 34.4% of patients. Peripheral blood counts normalized in 6.3% of patients while hematologic improvement was achieved in 25%. The median time to AML in responding patients was 45 weeks, while AML occurred after a median of 14 weeks in non-responding patients (P= .038). The median survival of all patients was 60 weeks; the median survival of responders was 74 weeks compared with 26 weeks in non-responders (P= .047). In this retrospective analysis, 5-AZA was associated with a survival advantage in responding patients with higher risk MDS or sAML. These favorable results suggest that patients may benefit even from a limited number of courses of 5-AZA. A randomized controlled clinical trial is required to prospectively validate these findings.
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PMID:A limited number of 5-azacitidine cycles can be effective treatment in MDS. 1869 67

Major therapeutic progress has been accomplished in leukemia and myelodysplastic syndrome (MDS) over the past 40 years, which may not be fully appreciated by the larger medical community. The objective of this review was to briefly highlight the treatment breakthroughs in leukemia and MDS. Therapeutic progress happened through better understanding of disease pathophysiologies and rational development of targeted agents, like imatinib mesylate in chronic myeloid leukemia (CML), and through astute, empirical discoveries in the clinic, like all-trans retinoic acid and arsenic trioxide in acute promyelocytic leukemia (APL) and chlorodeoxyadenosine in hairy cell leukemia (HCL). Today, the 5- to 10-year survival rates in patients with APL and HCL exceed 80%. In patients with CML, imatinib therapy has been associated with estimated 5- to 7-year survival rates from 85% to 90%. In patients with adult acute lymphocytic leukemia, modern intensive regimens have improved the 5-year survival rates from 20% up to 40%. In patients with chronic lymphocytic leukemia, chemoimmunotherapy recently produced high rates of quality responses and improved long-term outcome. In younger patients with acute myeloid leukemia (AML), the 5-year survival rates range from 40% to 50%, although elderly AML remains a therapeutic challenge. In patients with MDS, it was recently demonstrated that epigenetic therapy with hypomethylating agents improved survival. Much therapeutic progress has been witnessed in leukemia and MDS, and much more is expected to occur soon.
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PMID:Therapeutic advances in leukemia and myelodysplastic syndrome over the past 40 years. 1879 33

Acute myelogenous leukemia (AML) patients (24 consecutive patients, median age 71 years, 17 high-risk disease) were treated with all-trans retinoic acid, theophylline and valproic acid. Among 22 evaluable patients 9 responded with increased normal peripheral blood cell counts. The responses could be classified as hematological improvement according to response criteria for patients with myelodysplastic syndromes (MDS) for four patients only. The nine patients with increased normal cell counts had a median survival from start of therapy of 147 days compared with 48 days for the other patients. Four patients fulfilling the MDS criteria had a survival ranging from 112 to 644 days. The treatment was associated with decreased in vitro cytokine-dependent AML cell proliferation and increased blood levels of Endocan and angiopoietin-2 both for responders and non-responders. We conclude that the therapy causes disease stabilization for a subset of AML patients.
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PMID:A subset of patients with high-risk acute myelogenous leukemia shows improved peripheral blood cell counts when treated with the combination of valproic acid, theophylline and all-trans retinoic acid. 1900 87


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