Objectives: Ovarian cancer is the most common cause of death from gynecologic cancer in women. Because of the lack of effective screening and warning sign, 60-70% of patients were diagnosed at advanced stage. At present the treatment of advanced ovarian cancer is cytoreductive surgery followed by chemotherapy, and the overall response rate is 70-80%. But 50-75% of responders will relapse within about 18 -24 months. Therefore, new strategies of treatment, for examples, immunotherapy or targeted therapy, are necessary. This study is to evaluate the anti-tumor effect of activated natural killer (NK) cells in xenograft mouse model with epithelial ovarian cancer(EOC). Methods: We have made the OVCAR3-Luc stable cell line by transient transfection of pGL3-Luciferase (G418) gene. The xenograft mouse model of EOC was constructed by the intra-peritoneal injection of OVCAR3-Luc ovarian cancer cell line to the NOD/scid mice. After we confirm the tumor formation with IVIS spectrum, activated NK cells were injected with intra-peritoneal route. There was no treatment to the negative control and paclitaxel (10mg/kg) was used to the positive control. The tumor growth was evaluated by serial IVIS spectrum and biopsy at 8 weeks after any treatment. Results: Activated NK cells were injected at concentration 1 × 107 cells per mouse with intra-peritoneal route. This procedure was repeated 5 times. The NK cells significantly inhibited the tumor growth of OVCAR3-Luc-induced NOD/scid mice, up to the 57.1% comparing the negative control. Although paclitaxel decrease 69.3% of the tumor growth, it is not different to that of NK cell treating mice. Furthermore, side effects involving hair loss, abnormal behavior and weight low were not shown in NK cell-injected mouse models. Conclusion: We confirmed that activated NK cells are able to inhibit ovarian tumor growth without side effect in xenograft models. Therefore, this research demonstrates that NK cell-based immunotherapy might be desirable to the patients with ovarian cancer as an adoptive immunotherapy.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 3513. doi:1538-7445.AM2012-3513