On the other hand, it was shown that hMSCs expanded for a prolonged time in in vitro hypoxia exhibit a change in their gene expression profile, in particular for three transcription factors (c-MYC, p53, and HIF1) that are frequently amplified, mutated, or overexpressed in cancer [38] and that this led to a higher transformation frequency after exposure of the cells to NiSO4. Here, TP53 is linked to cancer.