Abstract: Objective To establish an animal model of human osteosarcoma in nude mice, and use the model to investigate the antitumor activity of Trichostatin A with this animal model. Methods Nude mice received MNNG/HOS cell suspensions was subcutaneously injected into nude mice with the concentration of 2×10⁶ to develop growing tumor. Tumor-bearing mice were examined by Micro-CT imaging system; the tumor tissue was observed by microscopic examination after HE staining. The animal model of human osteosarcoma was established. When subcutaneous tumors were 10-20 mm, mice were randomly divided into the control group (n=6), TSA group (n=6) and CTX group (n=6), the TSA group was treated with TSA (1 mg/kg); CTX group was treated with CTX (20 mg/kg); and control animals were treated with vehicle containing saline with 5% DMSO. Mice were injected every three days. Measure the size of tumor and the weight of tumor-bearing mice was recorded. The tumor growth curve and nude mice weight change curve were drawn. Results Two weeks after the inoculation, local tumor was formed. Four weeks later, bone destruction was visible in Micro-CT imaging system; osteoid tissue formed by osteosarcoma cells could be seen under light microscope and osteoplastic process was ubiquitous. TSA significantly inhibited tumor growth (P<0.05). No significant body weight difference or signs of overt toxicity was noticed between TSA and control group. Conclusion The animal model of osteosarcoma was successfully established, which will provided the basis of animal experiments for clinical studies of osteosarcoma. TSA significantly inhibited tumor growth of osteosarcoma in vivo.

Key words: Osteosarcoma, MNNG/HOS cell line, Animal model, Trichostatin A