In an independent study, Park et al. observed similar upregulation in VEGF expression levels, as well as expression of hypoxia-inducible factor (HIF)-1α in androgen-independent human prostate cancer cells PC-3, treated with norepinephrine and isoproterenol, an effect that was mechanistically mediated through increased activity of the cAMP/PKA pathway [154, 163]. This evidence concerns the gene VEGFA and prostate cancer.