ACTA2 and myeloproliferative neoplasm: To validate this, we generated murine mesenchymal stromal cells (mMSCs) transduced with a Runx1 overexpression plasmid significantly upregulated fibrosis-related genes such as Fn1, Col1a1, and Acta2 compared to the empty vector (EV) control, suggesting a role for Runx1 in the dysregulated hematopoiesis in MPN but also showing a direct link to the fibrotic transformation (Figure 2F).