<p><b>OBJECTIVES</b>To construct a
hepatoma directed
gene delivery system which could transfer preS2
antisense RNA to
liver cancer cells specifically, and to explore a new
therapeutic strategy for
hepatocellular carcinoma by blocking
hepatitis B virus (HBV) with
antisense RNA targeting
hepatocellular carcinoma.</p><p><b>
METHODS</b>GE7 and HA20 were synthesized and mixed with pEBAF-as-preS2, a hepatocarcinoma specific HBV antisense expression vector, to construct a novel HBV
antisense RNA delivery system named AFP-enhancing 4-
element complex.
Nude mice bearing hepatocelluar
carcinoma cells HepG2.2.15 were injected with AFP-enhancing 4-
element complex via a
tail vein. Total
RNA from
tissues was extracted, and reversal transcription-ploymerase
chain reaction (RT-PCR) was used to detect the expression of preS2. Different doses of AFP-enhancing 4-
element complex was injected into
nude mice at different
time points, and
tumor diameter was measured.</p><p><b>RESULTS</b>AFP-enhancing 4-
element complex was constructed successfully. RT-PCR showed preS2
antisense RNA delivered by AFP-enhancing 4-
element complex only expressed in
liver tumor HepG2.2.15
cells of the
mice. After the
treatment of AFP-enhancing 4-
element complex with
dose of 0.2 micro g per
mouse (once a week for 4 weeks), the mean
tumor diameter of
nude mice was significantly shorter than that of the
control groups (0.995 +/- 0.35 cm vs 2.125 +/- 0.25 cm, P < 0.01).</p><p><b>CONCLUSIONS</b>An HBV
antisense RNA gene delivery system targeting
hepatocellular carcinoma, AFP-enhancing 4-
element complex, was constructed successfully. PreS2
antisense RNA expressed specifically in hepatocelluar
carcinoma cells significantly inhibits
tumor growth of
mice bearing hepatocarcinoma HepG2.2.15 and may have
therapeutic potential in HBV related hepatocarcinoma.</p>