(125)I-labeled anti-bFGF monoclonal antibody inhibits growth of hepatocellular carcinoma.

Aim: To investigate the inhibitory efficacy of (125)I-labeled anti-basic fibroblast growth factor (bFGF) monoclonal antibody (mAb) in hepatocellular carcinoma (HCC).
Methods: bFGF mAb was prepared by using the 1G9B9 hybridoma cell line with hybridization technology and extracted from ascites fluid through a Protein G Sepharose affinity column. After labeling with (125)I through the chloramine-T method, bFGF mAb was further purified by a Sephadex G-25 column. Gamma radiation counter GC-1200 detected radioactivity of (125)I-bFGF mAb. The murine H22 HCC xenograft model was established and randomized to interventions with control (phosphate-buffered saline), (125)I-bFGF mAb, (125)I plus bFGF mAb, bFGF mAb, or (125)I. The ratios of tumor inhibition were then calculated. Expression of bFGF, fibroblast growth factor receptor (FGFR), platelet-derived growth factor, and vascular endothelial growth factor (VEGF) mRNA was determined by quantitative reverse transcriptase real-time polymerase chain reaction.
Results: The purified bFGF mAb solution was 8.145 mg/mL with a titer of 1:2560000 and was stored at -20 °C. After coupling, (125)I-bFGF mAb was used at a 1: 1280000 dilution, stored at 4 °C, and its specific radioactivity was 37 MBq/mg. The corresponding tumor weight in the control, (125)I, bFGF mAb, (125)I plus bFGF mAb, and (125)I-bFGF mAb groups was 1.88 ± 0.25, 1.625 ± 0.21, 1.5 ± 0.18, 1.41 ± 0.16, and 0.98 ± 0.11 g, respectively. The tumor inhibition ratio in the (125)I, bFGF mAb, (125)I plus bFGF mAb, and (125)I-bFGF mAb groups was 13.6%, 20.2%, 25.1%, and 47.9%, respectively. Growth of HCC xenografts was inhibited significantly more in the (125)I-bFGF mAb group than in the other groups (P < 0.05). Expression of bFGF and FGFR mRNA in the (125)I-bFGF mAb group was significantly decreased in comparison with other groups (P < 0.05). Groups under interventions revealed increased expression of VEGF mRNA (except for (125)I group) compared with the control group.
Conclusion: (125)I-bFGF mAb inhibits growth of HCC xenografts. The coupling effect of (125)I-bFGF mAb is more effective than the concomitant use of (125)I and bFGF mAb.