Inhibitory Effects Of¹²⁵I Radioactive Particle Implantation Combined With CIK Cells On The Growth Of Human Hepatocellular Carcinoma Xenografts In Nude Mice

Objective To observe the inhibitory effects of¹²⁵I interstitialbrachytherapy combined with cytokine-induced killer （CIK） cells on thegrowth of human hepatocellular carcinoma xenografts in nude mice.Methods Peripheral blood mononuclear cells were taken from healthpeople and different cytokines were added to promote the mature of CIKcells. CIK cell phenotype was detected by FCM; CD3⁺CD56⁺doublepositive cells reaching20%was considered as qualified. BALB/c nude micewere transplanted with SMMC-7721HCC cell to establish tumor model andthe mice were divdied into¹²⁵I radioactive particle group（group A）, CIK cellgroup（group B）,¹²⁵I radioactive particle+CIK cell group（group C） andblank control group （group D）. Treatment was given respectively, diametersof tumors in each group were measured every4d and inhibitory effects ofdifferent treatments on growth of human hepatocellular carcinomaxenografts were observed. Pathological changes of xenografted tumors were detected by HE staining, histopathology and apoptotic rate of these tumorswere examined by TUNEL; expressions of Ki-67protein were detected byimmunohistochemical staining.Results¹²⁵I radioactive particle implantation combined with CIK cellsintravenously can significantly inhibit the growth of human hepatocellularcarcinoma xenografts in nude mice. In group C, tumor volume was（0.21±0.08） cm³, less than those in group A （0.62±0.11） cm³, group B（1.89±0.71） cm³and group D（3.33±0.26） cm³, with significantdifferences among groups （F=155.7, P <0.001）. Inhibition rate in group Cwas93.71%, significantly higher than those in group A （81.33%） and groupB （43.06%）. Immunohistochemical staining revealed that mean absorbancevalue of Ki-67protein in each group were: group C （0.481±0.063）, group A（0.592±0.104）, group B （0.669±0.120）, group D （0.797±0.113） respectively,with statistically significant differences among groups （F=24.33, P <0.001）.According to the results of TUNEL, apoptotic mean absorbance value ingroup C was （0.859±0.067）, higher than that in group A （0.756±0.055） andgroup B （0.517±0.051） respectively, with statistically significant differencesin each group（F=318.37, P <0.001）.Conclusions Permanently implanted radioactive¹²⁵I particle combinedwith CIK cells immune therapy can significantly inhibit the growth ofhuman hepatocellular carcinoma xenografts in nude mice, restrain theproliferation of tumor and induce apoptosis in vivo, thus it could become a significantly therapy for hepatoma.