Upstream of DARPP-32, dopamine D2 receptor agonists have been shown to inhibit lung tumour angiogenesis,6 and clinical trials of selective dopamine D2 and D3 receptor antagonists have demonstrated anti-cancer efficacy in several cancer types other than lung.7 Recent reports suggest aberrant DARPP-32 overexpression promotes oncogenesis in lung,8 gastric,9 colon,10 prostate,11 oesophagus12 and breast adenocarcinomas13 through regulation of proliferation,14 survival,15 migration,8 invasion,16 and angiogenesis.17 However, the role of DARPP-32 in neuroendocrine tumours remains unexplored. Here, PPP1R1B is linked to cancer.