Figure 6.

Signaling pathways that regulate cancer cell metabolism. Tumor cells have gain-of-function mutations in PI3K or loss-of-function mutations in PTEN, the negative regulator of PI3K, that alleviate the necessity of growth factor–dependent signaling. MYC, which is aberrantly activated in a variety of cancers, increases the expression of many genes involved in anabolic pathways that support cell proliferation and growth. Metabolism can also regulate signaling, in part, through production of mitochondrial ROS and acetyl-CoA. GLS, glutaminase; ACLY, ATP-citrate lyase; CS, citrate synthetase. (Adapted from Ward and Thompson 2012.)