The protein encoded by this gene is a serine/threonine kinase that regulates cell polarity and energy metabolism and functions as a tumor suppressor. Mutations in this gene have been associated with the autosomal dominant Peutz-Jeghers syndrome, as well as with skin, pancreatic, and testicular cancers. [provided by RefSeq, May 2022] see less The protein encoded by this gene is a serine/threonine kinase that regulates cell polarity and energy metabolism and functions as a tumor suppressor. Mutations in this gene have been associated with the autosomal dominant Peutz-Jeghers syndrome, as well as with skin, pancreatic, and testicular cancers. [provided by RefSeq, May 2022]