LKB1-AMPK axis revisited.

The LKB1 tumor suppressor encodes a serine-threonine kinase whose substrates control cell metabolism, polarity, and motility. LKB1 is a major mediator of the cellular response to energy stress via activation of the master regulator of energy homeostasis, AMPK. While mutational inactivation of LKB1 promotes the development of many types of epithelial cancer, a recent report in Nature by Jeon et al. demonstrates that the LKB1-AMPK pathway can also have an unexpected positive role in tumorigenesis, acting to maintain metabolic homeostasis and attenuate oxidative stress thereby supporting the survival of cancer cells.