As expected, treatment of ARK2 cells with metformin or with AICAR increased AMPK phosphorylation at Thr172, consistent with AMPK activation (Figure 3c).13, 15 Together, these results support the hypothesis that AMPK activation by metformin contributes to let-7 upregulation in endometrial cancer cells. The gene discussed is AURKB; the disease is endometrial cancer.