[Analysis of Proliferation Characters of Bone Marrow Mesenchymal Stem Cells Derived from Patients with Myelodysplastic Syndrome].

Objective: To analyze the proliferation potential of bone marrow-derived mesenchymal stem cells (MSC) in patients with myelodysplastic syndrome (MDS).

Methods: The MSC derived from the 24 patients with newly diagnosed MDS (MDS-MSC group) and MSC derived from 15 patients with nutritional anemia (control group) in the Affiliated Hospital of Hebei University were used as the research objects. The proliferation potential of MSC was analyzed by colony-forming unit assay, doubling time, cumulative passaging, cell number after 10 days of culture with equal amount of MSC and MTT experiment. The mechanism of abnormal proliferation was analyzed by cell cycle experiment, apoptosis experiment and p21 gene expression assay.

Results: In the colony forming unit assay, the number of MDS-MSC colonies was 4.44±2.51, which was significantly lower than that of the control group (12.44±2.55)(P<0.01); the doubling time of MDS-MSC group was significantly longer than that of the control group (7.80±3.26 vs 3.63±0.85) (P<0.01); the number of MDS-MSC in 5×10 culture for 10 days was (39.40±14.18)×10, which was significantly lower than that of the control group ［(85.30±9.49)×10 ］(P<0.01); the number of cumulative passages in MDS-MSC group was 5.20±1.40, which was significantly lower than that in control group (11.60±1.96)(P<0.01); MTT results showed that the proliferation capability of MSC in MDS-MSC group was lower than that in the control group. The cell proportion of G/G phase in MDS-MSC group was higher than that in the control group, while the cell proportion of S phase was lower (P<0.05). The percentage of early apoptotic cells in MDS-MSC group was higher than that in control group (P<0.05); the relative expression level of p21 mRNA in MDS-MSC group was significantly higher than that in control group(P<0.01).

Conclusion: The proliferative capability of MDS-MSC is significantly reduced, which relates with the arrest of cell cycle in G/G phase, the increase of early apoptotic cells and senescent cells of the MDS-MSC.