Abnormal changes in the quantity and function of osteoblasts cultured in vitro in patients with myelodysplastic syndrome

Changes in bone marrow niches can lead to the occurrence of myelodysplastic syndrome (MDS). As an important part of the bone marrow niche, osteoblasts serve a key role in the progression of MDS. The present study investigated the quantity and function of osteoblasts and, through in vitro assays, detected changes in signaling pathways and the association with progression in MDS patients. The ratios of osteoprogenitors (CD34(+)OCN(+)) and OCN(+)CD34(−)Lin(−) osteoblasts in MDS patients were significantly less than those of normal controls. The results of this study demonstrated that the quantity and activity of osteoblasts in MDS patients were lower than those in normal controls. Furthermore the activity of osteoblasts in patients correlated with the severity of MDS. The quantity of osteoblasts cultured in vitro from high-risk and very high-risk MDS patients (WHO Classification-Based Prognostic Scoring System score 3–6) was decreased. The levels of T-cell immunoglobulin and mucin domain-containing 3 (TIM3) and Jagged 1 were also increased in the osteoblasts in vitro. These results indicated that osteoblasts are abnormally altered in MDS patients, and that there are associations between abnormal changes of osteoblasts and the severity of MDS.