Mitofusin-2 in cancer: Friend or foe?

Cancer is a category of disorders characterized by excessive cell proliferation with the ability to infiltrate or disseminate to other organs of the body. Mitochondrial dysfunction, as one of the most prominent hallmarks of cancer cells, has been related to the onset and development of various cancers. Mitofusin 2 (MFN2) is a major mediator of mitochondrial fusion, endoplasmic reticulum (ER)-mitochondria interaction, mitophagy and axonal transport of mitochondria. Available data have shown that MFN2, which its alterations have been associated with mitochondrial dysfunction, could affect cancer initiation and progression. In fact, it showed that MFN2 may have a double-edged sword effect on cancer fate. Precisely, it demonstrated that MFN2, as a tumor suppressor, induces cancer cell apoptosis and inhibits cell proliferation via Ca²⁺ and Bax-mediated apoptosis and increases P21 and p27 levels, respectively. It also could suppress cell survival via inhibiting PI3K/Akt, Ras-ERK1/2-cyclin D1 and mTORC2/Akt signaling pathways. On the other hand, MFN2, as an oncogene, could increase cancer invasion via snail-mediated epithelial-mesenchymal transition (EMT) and in vivo tumorigenesis. While remarkable progress has been achieved in recent decades, further exploration is required to elucidate whether MFN2 could be a friend or it's an enemy. This study aimed to highlight the different functions of MFN2 in various cancers.