Inhibition of AKT in human pancreatic, renal and colorectal cancer cells by four cardiac hormones.

Background: Protein kinase-B (AKT) is a serine/threonine protein kinase that has a key role in cell proliferation and cancer cell invasiveness. Four cardiac peptide hormones, namely vessel dilator, atrial natriuretic peptide (ANP), kaliuretic peptide, and long-acting natriuretic peptide (LANP) have anticancer effects both in vitro and in vivo.

Methods: Four cardiac hormones were examined for their ability to inhibit AKT, measured with a solid-phase enzyme-linked immunosorbent assay (ELISA) in human colorectal, pancreatic, and renal cancer cells.

Results: Vessel dilator, kaliuretic peptide, ANP, and LANP maximally reduced the concentration of AKT by 47%, 45%, 52%, and 46% in human colorectal cancer cells (p<0.0001), by 60%, 61%, 64%, and 59% in human pancreatic carcinoma cells (p<0.0001), and by 31%, 32%, 31%, and 31% in renal adenocarcinoma cells (p<0.001).

Conclusions: These four cardiac hormones are significant inhibitors of AKT in human cancer cells, as part of their anticancer mechanism(s) of action.