[Cytogenetic abnormalities in bone marrow mesenchymal stem cells from patients with myelodysplastic syndrome].

This study was aimed to investigate the cytogenetic characteristics of hematopoietic cells (HC) and bone marrow mesenchymal stoma cells (BMMSC) isolated from patients with myelodysplastic syndrome (MDS) and healthy individuals as normal controls, and to clarify whether HC and BMMSC are simultaneously involved and participate in pathogenesis and development of MDS. Both marrows of 22 newly diagnosed patients with MDS and 7 healthy individuals were collected; BMMSC were isolated and amplified by using established culture system, as well as were identified according to morphologic features and surface antigens detected by flow cytometry; the characteristics of BMMSC from MDS patients were analyzed; the BMMSC karyotyping analysis of MDS patients was performed by banding of HC and BMMSC with pancreatin-Giemsa technique (GTG) and in accordance with ISCN (2005) requirements; the cytogenetic characteristics of HC and BMMSC were compared. The results showed that in vitro culture system for isolation and amplification was successfully established. The light microscopy and flow cytometry confirmed that BMMSC possessed characteristics showing long and thin spindle form and expressing CD29, CD73, CD90 antigens, and unexpressing CD34, CD45 antigens. In BMMSC of 14 MDS patients (64%), the cytogenetic abnormalities were found usually involving the loss of chromosomal material (92%), among which clonal loss was observed in 7 cases (50%). The detection indicated a random loss of chromosomal material in significant proportion of BMMSC. A high proportion of chromosomal material random loss may be a marker of chromosomal instability in BMMSC of MDS patients, the detection also showed that completely consistent aberration types did not exist between HC and BMMSC. The aberrations were observed in 3 cases of MDS with normal karyotype of HC, its aberration rate (33%) was obviously lower than that in MDS patients with abnormal karyotypes (92%). It is concluded that the cytogenetic abnormalities exist in BMMSC of MDS patients, the unbalanced aberration of chromosomal materials may be a genetic instability marker of BMMSC. The difference of aberration types in BMMSC from HC suggests that genetic susceptibility of BMMSC and HC is similar, but no completely identical, which indicates the potential involvement of BMMSC in pathogenesis of MDS. Studying this potential role of BMMSC can be helpful to further understanding of MDS biological characteristics and provide the new approaches for diagnosis and therapy of MDS.