Figure 2.

Role of ROS in signal transduction.

ROS induce activation of PI3K/AKT/mTOR survival signaling leads to the activation of mainly 2 signaling pathways: Ras-MAPK, which results in cell proliferation, and PI3K-Akt-eNOS, which results in metabolic modulation and cell survival. Hypoxia causes the activation of HIFα-HIFβ, which further activates VEGF, an angiogenic growth factor. In cancer cell ROS, high concentration of ROS activates survival pathway and inactivates PTEN pathway which initiates apoptosis. ROS indicate reactive oxygen species; PTEN, phosphatase and tensin homolog; VEGF, vascular endothelial growth factor.