Tumour targeting of Auger emitters using DNA ligands conjugated to octreotate

Abstract

Purpose: The objective of the study was to conjugate the DNA binding ligand para-[125I]-iodoHoechst to octreotate, and to explore the tumour targeting potential of this conjugate in the octreotate-somatostatin receptor system. Methods: We synthesized a Hoechst analogue containing a tri-butylstannyl group in the para position of phenyl ring, conjugated it to the N-terminal amino group of octreotate and prepared 125I-labelled conjugate by iododestannylation. We used the somatostatin receptor (SSTR2) over-expressing cell line A427-7 derived from its parent A427 human non-small cell lung carcinoma cell line to investigate SSTR2 affinity and receptor-mediated internalisation of the conjugate, and..