Figure 8.

The role of Lon overexpression in tumorigenesis and malignancy progression. Several stresses in tumor microenvironment, hypoxia, oxidative stress, genetic instability, upregulate the level of mitochondrial Lon. Upregulation of Lon increases the protein level of NDUFS8 in mitochondrial complex I, leading to the increased concentration of mitochondrial ROS from complex I. Increased ROS levels in cancer cells promote cell survival, transformation, and malignancy progression, for example, cell migration and EMT, through activation of MAPK and/or Ras-ERK1/2 signaling