VEGFA and neoplasm: Although our experiments failed to demonstrate any effects of chaetocin on phospho-VEGFR-1 levels in vivo (suggesting that VEGF activity in treated and untreated SKOV3 tumours was similar), the results of others indicate instead that disruption of HIF-1α signalling may nevertheless have an important role in the in vivo effects of chaetocin under at least some circumstances.