The data suggest that in addition to the up-regulation of NRP-1 that in turn up-regulated the expression of the angiogenic molecules such as VEGF165, VEGFR-2 and PECAM, an up-regulation of OCT3/4 and c-Myc together with a down-regulation of KLF4 may also contribute towards the aggressive growth and angiogenesis of the HT1080 tumour under hypoxia. Here, KLF4 is linked to neoplasm.