When the myotubes from the MyoD-transduced fibroblasts were exposed to prednisolone for 11 to 16 days of our differentiation protocol, we found that there was no significant difference in expression of utrophin between no-treatment and prednisolone treated groups in human in vitro DMD model that we established (Figure 5A). Here, UTRN is linked to Duchenne muscular dystrophy.