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)

The human genome contains at least 50 copies of the human endogenous retrovirus K (HERV-K) family which is related to the mouse mammary tumor virus (MMTV). Some members have been shown to be transcriptionally active and to have large open reading frames. Using the RT-PCR method we have investigated the HERV-K env transcription pattern in several malignant tissues and in peripheral blood mononuclear cells PBMCs). Samples were derived from chronic myelogenous leukemia (CML), breast cancer, colon cancer, high and low grade non-Hodgkin's lymphomas, Hodgkin's disease, myelodysplastic syndrome, thyroid adenoma (TA) and from PBMCs of patients with breast cancer, gastric cancer, and of healthy individuals. We found abundant HERV-K env transcripts in all tissues under investigation. Using HERV-K 10 specific primers for amplification we detected in addition to transcripts with high homology to HERV-K 10 (ca. 96% homology on the amino acid level) also transcripts of low homology to HERV-K10 (ca. 71%). Interestingly, all solid tissues containing high percentages of malignant cells such as breast cancer, colon carcinoma, low and high grade non-Hodgkin's lymphomas showed exclusively HERV-K env related transcripts with low homology to HERV-K 10. In contrast, in samples containing only a low proportion of malignant cells or no malignant cells at all we observed both types of transcripts. Thus, our data suggest that the expression pattern of HERV-K elements in human cells is very heterogenous and subjected to a complex transcriptional regulation.
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PMID:Two groups of endogenous MMTV related retroviral env transcripts expressed in human tissues. 942 77

Myelodysplastic syndromes (MDS) are clonal stem cell hematologic disorders that evolve to acute myeloid leukemia (AML) and thus model multistep leukemogenesis. Activating RAS mutations and overexpression of BCL-2 are prognostic features of MDS/AML transformation. Using NRASD12 and BCL-2, we created two distinct models of MDS and AML, where human (h)BCL-2 is conditionally or constitutively expressed. Our novel transplantable in vivo models show that expression of hBCL-2 in a primitive compartment by mouse mammary tumor virus-long terminal repeat results in a disease resembling human MDS, whereas the myeloid MRP8 promoter induces a disease with characteristics of human AML. Expanded leukemic stem cell (Lin(-)/Sca-1(+)/c-Kit(+)) populations and hBCL-2 in the increased RAS-GTP complex within the expanded Sca-1(+) compartment are described in both MDS/AML-like diseases. Furthermore, the oncogenic compartmentalizations provide the proapoptotic versus antiapoptotic mechanisms, by activating extracellular signal-regulated kinase and AKT signaling, in determination of the neoplastic phenotype. When hBCL-2 is switched off with doxycycline in the MDS mice, partial reversal of the phenotype was observed with persistence of bone marrow blasts and tissue infiltration as RAS recruits endogenous mouse (m)BCL-2 to remain active, thus demonstrating the role of the complex in the disease. This represents the first in vivo progression model of MDS/AML dependent on the formation of a BCL-2:RAS-GTP complex. The colocalization of BCL-2 and RAS in the bone marrow of MDS/AML patients offers targeting either oncogene as a therapeutic strategy.
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PMID:BCL-2 and mutant NRAS interact physically and functionally in a mouse model of progressive myelodysplasia. 1808 95

Myeloid sarcoma is a tumor mass with extramedullary growth pattern, composed of myeloblasts or immature myeloid cells. The development of myeloid sarcoma may precede or concur with acute or chronic myeloid leukemia (AML or CML) or other myeloproliferative diseases or myelodysplastic syndromes (MDS). Isolated myeloid sarcoma of the breast is very rare. A case is presented of a 25-year-old, previously healthy woman that presented to our department for a palpable node, 5 x 2 cm in size, in the upper medial quadrant of her left breast. Fine needle aspiration (FNA) produced a sample consisting of medium sized blasts. Additional work-up revealed anemia, thrombocytopenia and leukocytosis, along with atypical blasts detected in peripheral blood and bone marrow smear. Based on the morphology, cytochemical characteristics and immature cell immunophenotype, it was considered a case of acute myeloid leukemia without maturation. In spite of intensive chemotherapy, the patient died within a year of diagnosis. In cases of isolated breast myeloid sarcoma, the diagnosis can be missed if the possibility of myeloid sarcoma is not remembered on differential diagnosis of a breast neoplasm.
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PMID:Myeloid sarcoma involving the breast. 2069 44