OPA1 and thyroid tumor: The fact that both the pro-fusion proteins Mfn2 and Opa1 were more expressed in oncocytic thyroid tumors than in their non-oncocytic counterparts may be related to other known cellular of these proteins: Mfn2-dependent ER-mitochondria tethering and Opa1 anti-apoptotic role in maintaining a proper cristae structure[27,28].