Mesenchymal stem cells in patients with chronic myelogenous leukaemia or bi-phenotypic Ph+ acute leukaemia are not related to the leukaemic clone
Wöhrer, S.; Rabitsch, W.; Shehata, M.; Kondo, R.; Esterbauer, H.; Streubel, B.; Sillaber, C.; Raderer, M.; Jaeger, U.; Zielinski, C.; Valent, P.
Anticancer Research 27(6b): 3837-3841
2007
ISSN/ISBN: 0250-7005 PMID: 18225540 Document Number: 610723
Human mesenchymal stem cells (MSCs) are thought to be multipotent cells which primarily reside in the bone marrow. Besides their well-known ability to replicate as undifferentiated cells and to differentiate into diverse lineages of mesenchymal tissues, they were recently suggested to also give rise to haematopoietic and leukaemic/cancer stem cells. In this study, the relationship between MSCs and leukemic stem cells in patients with either chronic myelogenous leukaemia (CML) or the more primitive variant, Ph+ bi-phenotypic leukaemia was investigated. Cultured MSCs from 5 patients with CML and 3 patients with bi-phenotypic Ph+ leukaemia, all of them positive for BCP-ABL, were analysed with conventional cytogenetics, fluorescence in situ hybridisation (FISH) and polymerase chain reaction (PCR) for the presence of t(9;22) and BCR-ABL. MSCs were characterised phenotypically with surface markers (+CD73, +CD90, +CD105, -CD34, -CD45) and functionally through their potential to differentiate into both adipocytes and osteoblasts. MSCs could be cultivated from seven patients. These cells were BCR-ABL negative when analysed with conventional cytogenetics and FISH. Further cytogenetic analysis revealed a normal set of chromosomes without any aberrations. Two patients were BCR-ABL-positive when analysed with PCR, probably as a result of MSC contamination with macrophages. MSCs in patients with CML or Ph+ bi-phenotypic leukaemia are not related to the malignant cell clone.