Editors' ChoiceCancer

Help for Starving Cells

Science Signaling  27 Nov 2012:
Vol. 5, Issue 252, pp. ec306
DOI: 10.1126/scisignal.2003799

As tumors grow larger, individual tumor cells respond to the dwindling supply of nutrients by changing the way they produce energy. The enzyme pyruvate kinase isoform M2 (PKM2) is an important component of this “metabolic reprogramming.” In a study aimed at identifying how PKM2 is regulated, Keller et al. found that a cellular metabolite called SAICAR stimulates PKM2 activity and promotes cancer cell survival when glucose is limited. SAICAR is an intermediate in the pathway for de novo biosynthesis of nucleotides and its interaction with PKM2 may help cells coordinate their mode of energy generation with nutrient conditions.

K. E. Keller, I. S. Tan, Y.-S. Lee, SAICAR stimulates pyruvate kinase isoform M2 and promotes cancer cell survival in glucose-limited conditions. Science 338, 1069–1072 (2012). [Abstract] [Full Text]