The key proteins were in the high-scoring networks as well in networks 8 and 9 with NPPB and DPP4 (dipeptidylpeptidase 4) (network 1), PDE4A (phosphodiesterase 4A) and ADIPOQ (adiponectin) (network 2), CST3 (Cystatin-C) (network 8) and SERPINC1 (antithrombin-III) (network 9) present in most cardiovascular diseases selected. The gene discussed is DPP4; the disease is cardiovascular disorder.