There are many studies reporting the alteration in miRNA expression in the long-term cultures. But will there be any significant changes even when P2/P3 MSC cells are used for differentiation (adipo, osteo or chondro)? Or is it due the time taken for it to differentiate which makes the loss of small RNA? In the sense, differentiation usually takes upto 28 days, so do the cells undergo apoptosis during the course of differentiation which influences the miRNA expression levels?