An isolated, purified or recombinant nucleic acid sequence is disclosed, comprising: (a) a sequence that encodes both an angiogenic factor antagonist and a vascular endothelial structure regulator; (b) a sequence substantially homologous to or that hybridizes to sequence (a) under stringent conditions; or (c) a sequence substantially homologous to or that hybridizes under stringent conditions to the sequence (a) or (b) but for the degeneracy of the genetic code; or (g) an oligonucleotide specific for any of the sequences (a), (b) or (c). Particular oligonucleotides (d) are those encoding the vascular endothelial structure regulator. Also described are methods for preparing the recombinant polynucleotide, proteins encoded by such polynucleotides and their use in gene or protein therapy for the treatment of conditions such as cancer.