TPX2 Derived Vaccine to Inhibit Tumorigenesis and Metastasis in Triple Negative Breast Cancer 

Abstract Background: triple negative breast cancer (TNBC) lacks of treatment approaches rather than other subtypes of breast cancer. However, it characterizes the highest the level of tumor infiltrating lymphocyte (TIL) than other subtypes, indicating the possibility of immunotherapy. Method: female BALB/c background mice are immunized with a TPX2 derived vaccine 4 consecutive times (once a week) from 6 weeks old, and then 4T1 cells are transplanted to the #4 mammary fatpad. Surface tumor volume and No. of lung metastasis were recorded. TIL and splenocyte was collected for T cell subgroup analysis by methods of flow cytometry and IFN-γ ELISPOT. Result: as a result, TPX2 derived vaccine shows moderate effect, shrinking the tumor volume from 804.4 to 504.5 mm3, and decreasing the number of lung metastasis from 16.6 to 6.0 in control group compared to vaccine group. CD8+ T cell ratio are obviously increased in TIL between vaccine group and control group (5.87% vs 3.37%, P=0.0012). And vaccine could induce strong immune response both in tumor site (87.6 vs 7.0, p=0.0004) and system (28.2 vs 3.8, p＜0.0001) through IFN-γ ELISPOT. Conclusion: our result indicated that TPX2 derived vaccine may be an effective approach to inhibit TNBC tumorigenesis and metastasis.