Influence of the cytosine content in liposome-coated 99Tcm-HYNIC-survivin ASODN on tumor bearing nude mice imaging / 中华核医学与分子影像杂志

ABSTRACT

Objective To investigate whether specific cellular uptake of 99Tcm-survivin-ASODN in nude mice bearing human HCC is influenced by its cytosine content.Methods Three kinds(A1,A2,A3) of synthesized survivin ASODN with three cytosine contents(10％,20％,30％),20 bases per single-strand were prepared.They were labeled with 99Tcm by conjugating with a bifunctional chelator HYNIC,purified through Cellufine GH-25 and then encapsulated with liposome.Antisense gene imaging and the biodistribution of 99Tcm-HYNIC-survivin ASODN in nude mice bearing HCC were performed.The data were analysed by Kruskal-Wallis H test.Results At 4 h post injection,all the 3 labelled compounds showed increased uptake by tumor,liver and kidney.With increase in cytosine content,the uptake increased in kidney (％ID/g1.50±0.06,2.80±0.09 and 3.96±0.03),and decreased in tumor (％ID/g2.08±0.08,1.69±0.01 and 1.20±0.09).T/NT in imaging (4.49-4.93,4.12-4.21,3.35-3.85;H=12.50,P＜0.05) and in biodistribution (4.08-4.94,4.02-4.18,3.66-3.85;H=10.82,P＜0.05) were all significantly different.Conclusion ASODN with lower cytosine content shows higher uptake by HCC tumor cells and less stasis in kidneys,thus providing better quality in antisense gene imaging.