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)

Myelodysplastic syndrome (MDS) is a heterogeneous hematopoietic stem cell disorder characterized by bone marrow dysplasia and peripheral cytopenias. Eighty percent of patients found to have MDS are older than 60 years and therefore not eligible for the only potentially curative therapy, bone marrow transplantation. Currently, there is no standard for treating MDS; therapies range from supportive care with transfusions or hematopoietic growth factors and low-intensity cytarabine therapy, to intensive anti-acute myeloid leukemia-type chemotherapy. Some of these treatments induce a limited hematologic response, but none consistently extends survival. Many are highly toxic. More than half of patients with MDS die within 3 to 4 years of infections, bleeding complications, or progression to acute leukemia. Agents in development for MDS include all-trans retinoic acid (ATRA), decitabine, and thalidomide. Farnesyltransferase inhibitors modulate many of the cancer-signaling pathways implicated in MDS initiation or progression and may therefore be well suited for treatment of these biologically diverse hematologic malignancies. Phase I and II clinical studies in our center show that the oral FTI ZARNESTRA (formerly R115777, Ortho Biotech Oncology, Raritan, NJ) has promising anti-MDS activity, suggesting that further investigation of this agent and of this class in MDS is warranted.
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PMID:Myelodysplastic syndrome overview. 1221 89

Significant advances have been made in the development of targeted interventions for hematologic malignancies. Progress has been made in defining the molecular pathogenesis of human leukemias. Data indicate that nonrandom, somatically acquired translocations, inversions, and other abnormalities occur in many acute leukemias. In the treatment of acute promyelocytic leukemia (APL), targeted therapy with all-trans retinoic acid (ATRA) and anthracycline-based chemotherapy leads to dramatic improvements in disease-free survival. Imatinib mesylate, a signal transduction inhibitor that inhibits tyrosine kinase activity, the protein product of the ABL proto-oncogene, has remarkable activity in patients with chronic myeloid leukemia (CML) and Philadelphia chromosome-positive (Ph(+)) acute lymphoblastic leukemia (ALL). Farnesyltransferase inhibitors (FTIs), a promising class of agents that target multiple pathways including Ras proteins, are potential anticancer therapy for a wide range of malignancies, including leukemias and myelodysplastic syndromes (MDS). There also is evidence that recombinant human erythropoietin therapy (r-HuEPO) can benefit patients with chronic lymphocytic leukemia (CLL), multiple myeloma, and lymphomas. This supplement will discuss advances in our understanding of human leukemias, including the use of unconjugated monoclonal antibodies such as Campath-1H (Wellcome, Beckenham, UK, and Ilex Oncology, San Antonio, TX) and rituximab and immunoconjugates such as gemtuzumab ozogamicin and BL-22. Although these novel therapies are beginning to fulfill their promise, continued research efforts are needed to determine the optimal role of targeted therapy in acute and chronic leukemias.
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PMID:Advancing the treatment of hematologic malignancies through the development of targeted interventions. 1244 45

The retinoids are compounds structurally related to vitamin A. The most extensively studied agents in cancer medicine include all-trans-retinoic acid, 9-cis-retinoic acid, and 13-cis-retinoic acid. In addition to several described immune regulatory functions, these agents may exert their antineoplastic effects through the regulation of tumor suppressor genes such as RAR-beta2. The survival benefit provided to patients with acute promyelocytic leukemia (APL) after induction therapy with all-trans RA and the responses experienced by patients with cutaneous lesions from Kaposi's sarcoma and cutaneous T cell lymphoma treated with 9-cis RA and a selective rexinoid--bexarotene--respectively, led to their approval by the Food and Drug Administration during the last decade. As chemopreventive agents, retinoids have proven to effectively regress laryngeal papillomatosis and oral leukoplakia lesions. The ability of 13-cis-RA to prevent second primary malignancies in patients with carcinoma of the head and neck has also been demonstrated. Unfortunately, this intervention did not affect the primary tumor recurrence rates. The toxicity and efficacy of retinoids administered in combination with other biological and cytotoxic agents have also been explored in patients with renal cell carcinoma, breast cancer, myelodysplasia, prostate, cervix, and other malignancies with a broad range of reported responses. Further characterization of the molecular processes modulated by these agents will serve to better define their role in the prevention and treatment of human cancer and to tailor specific targeted therapies in combination with other compounds. Newer and more selective retinoids and rexinoids are completing phase I and phase II studies and hold promising.
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PMID:Clinical applications of retinoids in cancer medicine. 1275 24

Acute promyelocytic leukemia (APL) represents a biologic and clinically well-defined subtype of acute nonlymphocytic leukemia with specific morphologic and karyotypic characteristics. Although secondary leukemia and myelodysplastic syndromes (MDS) are the most frequent secondary neoplasms following chemotherapy for acute leukemia, their development after complete remission in patients with APL is uncommon. We describe the clinical and genetic features of two APL patients who achieved CR after chemotherapy and all-trans retinoid acid treatment and subsequently developed a MDS. Therapy-related MDS karyotype changes such as abnormalities of chromosomes 5 and 7 were found in the cytogenetic analysis. Since TP53 alteration was detected in one case, possible implications of these findings in the onset of MDS are discussed.
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PMID:Secondary myelodysplastic syndrome after treatment for promyelocytic leukemia: clinical and genetic features of two cases. 1278 55

Acute promyelocytic leukaemia (APL) may be characterized simultaneously as the most potentially rapidly fatal human acute leukaemia if untreated, yet the most frequently cured acute leukaemia if promptly diagnosed and treated without delay. Co-operative group and single-institution studies which include large numbers of patients with relatively long follow-up demonstrate that, with all-trans retinoic acid (ATRA) plus anthracycline-based chemotherapy, the majority of newly-diagnosed patients appear cured of their disease. The 5-year disease-free survival rates range from 75 to 85%. Early death is still observed in approximately 10% of patients and remains a difficult obstacle to increasing the cure rate. Prognostic factors which identify patients at high risk for recurrence are becoming increasingly recognized. Older age (over age 55-60 years), elevated white blood cell count at presentation (higher than 5,000-10,000/microl), and expression of CD56 unfavourably influence outcome. The treatment of such patients remains a challenge, although it is important to note that APL is the only type of AML in which a significant proportion of older patients may be cured. Because more patients are cured of their disease, potential long-term consequences may become increasingly recognized. These include the emergence of extramedullary disease, the development of secondary myelodysplasia or acute myeloid leukaemia and the potential for late-onset cardiac toxicity.
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PMID:Long-term follow-up and potential for cure in acute promyelocytic leukaemia. 1293 68

Acute myeloblastic leukemia represents a heterogeneous group of diseases. The diagnosis and prognosis is most accurately provided by pretreatment assessment of the clonal molecular genetic derangement responsible for the disease, often provided by cytogenetic analysis. Other prognostic features include patient age, antecedent myelodysplasia, prior chemotherapy, and the presence of FLT-3 mutations. Accurate assessment of prognosis permits a risk-adapted treatment approach to maximize probability of cure and minimize treatment-related toxicity. The majority of patients with promyelocytic leukemia with the PML/RARalpha fusion gene can be cured with an all-trans-retinoic acid and anthracycline-based treatment program. All other patients are typically given cytarabine and anthracycline-containing induction regimens, although some with particularly poor prognosis disease may be more appropriate candidates for experimental induction therapies. Postinduction treatments include further conventional chemotherapy, stem cell transplant strategies, and experimental approaches. Issues pertinent in selecting treatments for patients in the different risk categories are reviewed.
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PMID:Update in acute leukemia 2003: a risk adapted approach to acute myeloblastic leukemia in adults. 1512 39

Valproic acid (VPA) has been shown to inhibit histone deacetylase activity and to synergize with all-trans retinoic acid (ATRA) in the differentiation induction of acute myelogenous leukemia (AML) blasts in vitro. We treated 18 patients with myelodysplastic syndromes (MDS) and AML secondary to MDS (sAML/MDS) with VPA monotherapy (serum concentrations 346-693 microM [50-100 microg/mL]). Five patients received VPA and ATRA (80 mg/m(2)/d, days 1-7, every other week). Response according to international working group (IWG) criteria was observed in 8 patients (44%) on VPA monotherapy, including 1 partial remission. Median response duration was 4 months (range, 3-9 months). Four of 5 patients relapsing were treated with VPA + ATRA, 2 of them responding again. Among 5 patients receiving VPA + ATRA from the start, none responded according to IWG criteria, but 1 patient with sAML/MDS achieved a marked reduction in peripheral and marrow blasts. Thus, VPA is of therapeutic benefit for patients with MDS, and ATRA may be effective when added later.
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PMID:Treatment of myelodysplastic syndromes with valproic acid alone or in combination with all-trans retinoic acid. 1586 67

To explore therapeutic efficacy of androgens and low dose all-trans retinoic acid (ATRA) for myelodysplastic syndrome (MDS) patients, 55 patients of MDS were observed, including 41 cases of refractory anemia (RA), 11 cases of refractory anemia with excess of blasts (RAEB), 2 cases of refractory anemia with excess of blasts in transformation (RAEB-t) and 1 case of chronic myeloic-monocytic leukemia (CMML). These patients received danazol (600 mg/day) or stanazol (6 mg/day) and ATRA (10 mg/day) for at least 3 months. The results showed that according to MDS international working group response criteria, at the end of three months,complete remission (CR) was seen in 1 patient, partial remission (PR) was found in 2 patients. Hematologic improvement: major response (MaR) were seen in 15 patients, minor response (MiR) were seen in 4 patients. The total response rate was 35.8%. In conclusion, danazol or stanazol in combination with low dose ATRA are partialy effective in therapy for patients with low-risk myelodysplastic syndrome.
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PMID:[Low dose all-trans retinoic acid and androgen therapy for patients with myelodysplastic syndrome]. 1563 59

Gene abnormalities responsible for familial Pelger-Huet anomaly have been recently discovered. Abnormalities in sequence of Lamin B Receptor(LBR) gene results in a lack of LBR protein that is essential for chromatin-binding to nuclear membrane. In neutrophils lacking LBR protein shows abnormal bilobular or monolobular nuclear forms and hyper-condensed chromatin-aggregation. We re-analyzed distribution of such Pelger-Huet anomaly in other cell lineages; we found that not only neutrophils but erythroblasts, monocytes, lymphocytes, plasma cells, eosinophils and basophils are also carrying chromatin-hypercondensation. One third of megakaryocytes are also binucleated like neutrophils. We compared neutrophil morphology between familial Pelger-Huet anomaly and so called pseudo-Pelger-Huet anomaly observed in patients with myelodysplastic syndromes(MDS) and acute myeloid leukemia(AML). The neutrophils in MDS were much similar to those of the familial anomaly, but neutrophils of AML, such as t (8;21) M2-AML and t (15;17) M3-AML, showed more heterogeneous pattern in lobulation and chromatin-hypercondensation. Especially in M3, differentiation-induction by all-trans retinoic acid induced a marked neutrophilia with pseudo-Pelger-Huet anomaly without chromatin-hypercondensation. Lack of LBR protein in familial Pelger-Huet anomaly results in hypolobulation and chromatin-hypercondensation in neutrophils, but in other cells such as erythroblasts and lymphocytes only chromatin-hypercondensation can be observed. In contrast pseudo-Pelger-Huet anomaly are more heterogeneous in morphology compared to the familial anomaly. The lack of leukemic or MDS transformation in the familial anomaly is a sharp contrast to the neoplastic nature of the pseudo-Pelger-Huet anomaly. In conclusion, our morphological recognition of certain abnormality of cells shows an marked progression when genetic abnormality responsible for some of them are discovered, and often make us recognize a further heterogeneity in them. We, hematologists and technicians, must be well prepared to report our own observation of an un-explained morphological abnormality.
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PMID:[Nuclear abnormalities in Pelger-Huet anomaly; progress in blood cell morphology]. 1572 91

The LYL1 gene encodes a basic helix-loop-helix transcription factor involved in T-cell acute lymphoblastic leukemia. Using real-time quantitative RT-PCR assay, we found that the expression of LYL1 was at higher levels in the majority cases of acute myeloblastic leukemia (AML) or myelodysplastic syndrome when compared to normal bone marrow. Our study also showed that LYL1 was highly expressed in most AML cell lines and in CD34+ AML cells. To determine whether LYL1 had an affect on the phenotype and behavior of myeloid cells, we introduced full-length LYL1 cDNA into K562 cells using electroporation and U937 cells with retroviral infection. Both of the derivative cell lines with overexpression of LYL1 had an increased growth rate and clonogenecity. Forced expression of LYL1 in K562 cells enhanced spontaneous and hemin-induced erythroid differentiation but blocked spontaneous as well as PMA-induced megakaryocytic differentiation. Overexpression of LYL1 in U937 cells blocked all-trans retinoic acid-induced monocytic differentiation. The LYL1-transfected U937 cells were also more resistant to the cytotoxic drug cytarabine. These results demonstrate that LYL1 may play a role in early hematopoiesis and may be a potential oncogenic factor in AML.
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PMID:Oncogenic potential of the transcription factor LYL1 in acute myeloblastic leukemia. 1609 22


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