Detection of mi transcription factor (MITF) mRNA in a case of myelodysplastic syndrome and bone marrow mastocytosis.
Myelodysplastic syndromes (MDS) may be accompanied by systemic mastocytosis. The mechanisms which play a role in the evolution of mastocytosis, however, are not well understood. We report on a case of refractory and anemia with ringed sideroblasts (RARS), and co-existing bone marrow mastocytosis. Compact mast cell (MC) infiltrates were detected in bone marrow sections by immunohistochemistry using an antibody to tryptase. In addition, the MC were found to express c-kit, the tyrosine kinase receptor for MGF (mast cell growth factor = stem cell factor, SCF). Activating point mutations in the kinase domain of c-kit (often found in mastocytosis) were not detectable. However, the mononuclear cells (MNC) of the bone marrow expressed mRNA specific for MITF, a transcription factor that regulates expression of c-kit and differentiation of MC. Surprisingly, the c-kit ligand SCF was found to augment expression of MITF mRNA in bone marrow MNC. Whether this augmentation represents a general response (preventing loss of growth factor receptor expression during cell maturation) common to all types of hemopoietic progenitors, or is confined to (some forms of) mastocytosis, remains unknown.
Wimazal
F
F
Department of Internal Medicine I, University of Vienna, Austria.
Walchshofer
S
S
Baghestanian
M
M
Chott
A
A
Sperr
W R
WR
Kopp
C
C
Sillaber
C
C
Semper
H
H
Horny
H P
HP
Tröndle
U
U
Födinger
M
M
Schwarzinger
I
I
Lechner
K
K
Valent
P
P
D000368:Aged; D000753:Anemia, Refractory / Q000235:genetics / Q000473:pathology; D000756:Anemia, Sideroblastic / Q000235:genetics / Q000473:pathology; D001853:Bone Marrow / Q000473:pathology*; D004268:DNA-Binding Proteins / Q000235:genetics*; D015870:Gene Expression; D006801:Humans; D008297:Male; D008407:Mast Cells / Q000473:pathology; D008415:Mastocytosis / Q000175:diagnosis / Q000235:genetics*; D051739:Microphthalmia-Associated Transcription Factor; D009190:Myelodysplastic Syndromes / Q000175:diagnosis / Q000235:genetics*; D017354:Point Mutation / Q000235:genetics; D019009:Proto-Oncogene Proteins c-kit / Q000235:genetics; D012333:RNA, Messenger / Q000235:genetics*; D019089:Stem Cell Factor / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*
D004268:DNA-Binding Proteins; C497234:MITF protein, human; D051739:Microphthalmia-Associated Transcription Factor; D012333:RNA, Messenger; D019089:Stem Cell Factor; D014157:Transcription Factors; D019009:Proto-Oncogene Proteins c-kit