To further establish the relationship between HOXB7 and osteoblast differentiation of MPN MSCs, we generated a stable HOXB7-knock-down (HOXB7-KD) HS-5 cell line using lentiviral shRNA (Figure 4, A and B, and Supplemental Figure 4). Here, HOXB7 is linked to myeloproliferative neoplasm.