HMOX1 and cancer: We have previously shown that HIF1-α[23] as well as ROS-scavenging enzymes [4] are constitutively highly expressed in Spalax. Similar to our explanations of the failure to induce cancer in vivo in live Spalax animals, in vitro studies, using fibroblast cells, demonstrated a significant role in adaptive response to oxidative stress, at least in part, via expression of HO-1 [48].