Figure 3.

Summary of retrograde signaling pathways and mitochondrial stress responses in mitochondrial stress-induced cancer progression and carcinogenesis. Several mitochondrial alterations, such as mtDNA copy number changes, mtDNA mutations, mitochondrial enzyme defects, and mitochondrial dynamic changes, can induce mitochondrial dysfunction in cancer cells. Several retrograde signaling pathways, such as ROS, calcium, oncometabolites, exported mtDNA/mt-dsRNA, humanin, MOTS-c, UPR^mtand ISR, are involved in the mitochondrial stress responses. The retrograde mitochondrial stress response can affect several nuclear gene expressions and plays an important role in cancer progression. (A color version of this figure is available in the online journal.)