Four peptide hormones decrease the number of human breast adenocarcinoma cells

Background A family of six hormones, i.e. atrial natriuretic peptide, brain natriuretic peptide, C‐natriuretic peptide, long‐acting natriuretic peptide, vessel dilator, and kaliuretic peptide's main known biologic properties are sodium and water excreting and blood pressure lowering. Methods and materials These six hormones, each at their 1‐µm concentrations, were evaluated for their ability to decrease the number and/or proliferation of breast adenocarcinoma cells in culture for 24, 48, 72, and 96 h. Results Within 24 h, vessel dilator, long‐acting natriuretic peptide, kaliuretic peptide, atrial natriuretic peptide and 8‐bromo‐cyclic GMP, a cell‐permeable analogue of their intracellular mediator cyclic GMP (each at 1 µm), decreased the number of breast adenocarcinoma cells 60%, 31%, 27%, 40%, and 31%, respectively. There was no proliferation in the 3 days following this decrease in breast adenocarcinoma cell number. These same hormones decreased DNA synthesis 69% to 85% (P