Anti-metastatic Efficacy of Traditional Chinese Medicine (TCM) Ginsenoside Conjugated to a VEFGR-3 Antibody on Human Gastric Cancer in an Orthotopic Mouse Model

Background/Aim: The aim of the present study was to investigate the efficacy of a traditional Chinese medicine (TCM), VEGFR-3 antibody-conjugated ginsenoside Rg3 nanoemulsion (VRIN), targeting lymphangiogenesis, on the inhibition of tumor growth and metastasis in an orthotopic mouse model of human gastric cancer. Materials and Methods: An orthotopic nude-mouse model of gastric cancer was established with the red fluorescent protein (RFP)-expressing human gastric cancer cell line NUGC-4-RFP. The tumorbearing mice were treated with vehicle (0.2 ml normal saline every other day, iv), 5-FU (20 mg/kg once a week, i.p.) and VRIN (1 mg/kg every other day, i.v.). Real-time fluorescence imaging was performed to assess tumor inhibition in each group. Metastasis was evaluated by open fluorescence imaging at autopsy. The expression of lymphangiogenesis-related factors VEGF-C, VEDF-D and VEGFR-3 in the tumors were analyzed by immunohistochemistry and real-time RCP. Results: VRIN and 5-FU significantly inhibited primary tumor growth as compared to vehicle control (p<0.05). However, significant inhibition of lymph-node metastasis was only found in the VRIN-treated group (p<0.05). The expression of VEGF-C, VEGF-D and VEGFR-3 in the tumor was suppressed by VRIN treatment (p<0.05). Expression of VEGF-D and VEGFR-3 in the 5-FUtreated group was not significantly increased (p>0.05). No obvious toxicity was found in VRIN-and5-FU-treated groups. Conclusion: Lymphangiogenesis-targeted ginsenoside Rg3 immune-nanoemulsion inhibited tumor growth and reduced lymphatic metastasis by suppressing expression of VEGF-C, VEGF-D and VEGFR-3 in an orthotopic mouse model of human gastric cancer. Our study demonstrates the potential of TCM as an effective targeted treatment for metastatic gastric cancer.