FIGURE 4.

Oncogenic signals involving cholesterol. Some oncogenic signals initiated from AKT/mTOR, RTK/RAS, YAP/TAZ, or mutated p53 induce the activity of SREBP transcription factor, the major regulator of genes encoding cholesterol synthesis and uptake. Also, the activation of the GTP-binding proteins Ras, Rho, and Rac, which functions are involved in carcinogenesis, depends on the availability of cholesterol. In particular, Ras family proteins are prenylated by farnesyl-PP, whereas geranylgeranyl-PP prenylates proteins of the Rho and Rac families. These chemical modifications are mandatory for their activity.