AKT1 and colonic neoplasm: Leptin has been shown to inhibit serum-starvation and celecoxib-induced apoptosis in HT-29, T84 and Caco-2 colon cancer cells via Akt-dependent pathways [28,45] and inhibit butyrate-induced apoptosis in HT-29 cells, although in the latter study the effect of Akt was not examined [43].