Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0679427 (myeloblastosis)
 982 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Previous findings from this laboratory (Kim & Baluda, 1988) have shown that the proto-oncogenes ETS, FPS, MHT (RAF), MYC and REL are expressed in avian myeloblastosis virus (AMV)-transformed cells, whereas the MYB gene is repressed. In this study five different chicken hematopoietic tissues which contained varying concentrations of target cells for AMV transformation were analyzed to determine whether the expression of these proto-oncogenes resulted from, or was altered by, v-myb-induced leukemogenesis. Poly-A+ RNA from hematopoietic cells of 11-13 day yolk sac, 16 day embryonic spleen, 1 day post-hatch bursa of Fabricius, bone marrow and thymus, as well as from chicken embryonic fibroblasts (CEF) was examined by Northern blot analysis. All five proto-oncogenes were found to be expressed in the normal hematopoietic tissues. The ETS, MHT (RAF), MYC, and REL genes, but not FPS, were expressed in CEF. The expression of these five proto-oncogenes was not quantitatively or qualitatively altered in AMV-transformed myeloid cells as compared with their normal counterparts. While their expression is part of the hematopoietic phenotype of the target cells and as such is necessary for susceptibility to AMV transformation, it is not sufficient because thymocytes with a high level of expression are not transformed. This is in contrast to MYB expression, which is totally repressed in leukemic cells but probably not as a result of v-myb expression.
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PMID:Proto-oncogene expression in avian hematopoietic tissues. 188 13

The c-myb protooncogene as well as its transforming derivate, the v-myb oncogene code for transcription factors. They regulate transcription of specific target genes thus controlling proliferation, differentiation and apoptosis of hematopoietic cells. Up-regulation of the c-myb expression or rearrangement/amplification of the myb locus are often involved in leukemogenesis. Enforced myb expression blocks differentiation of various leukemic cell lines. Human promonocytes U937 can be induced to differentiate to monocyte/macrophage-like cells using phorbol esters or to granulocytes using retinoic acid. In order to investigate transforming capability of v-myb, we expressed the v-myb oncogene of avian myeloblastosis virus in U937 cells. We found that v-Myb efficiently suppressed formation of macrophages upon treatment with phorbol ester. Some features of granulocytic differentiation of retinoic acid-treated U937 cells were affected by the v-Myb protein as well. These results document that v-Myb is significantly involved in control of myeloid differentiation.
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PMID:v-Myb suppresses phorbol ester- and modifies retinoic acid-induced differentiation of human promonocytic U937 cells. 1850 38