PRKAA1 and neoplasm: βOHB increased the phosphorylation of Thr172 of AMP-activated protein kinase (AMPK), phosphorylation of Ser428 of LKB1, a tumor suppressor and a key regulator of AMPK activation20,21, peroxisome proliferator-activated receptor-coactivator 1α (PGC1α), and Sirt1.