Inhibition of Aurora-A Promotes CD8 T-Cell Infiltration by Mediating IL10 Production in Cancer Cells.

Intratumoral tumor-specific activated CD8 T cells with functions in antitumor immune surveillance predict metastasis and clinical outcome in human colorectal cancer. Intratumoral CD8 T cells also affect treatment with immune checkpoint inhibitors. Interestingly, inhibition of Aurora kinase A (Aurora-A) by its selective inhibitor alisertib obviously induced infiltration of CD8 T cells. However, the mechanisms by which inhibition of Aurora-A promotes infiltration of intratumoral CD8 T cells remain unclear. Our recent results demonstrated that conditional deletion of the gene or blockade of Aurora-A by alisertib slowed tumor growth in association with an increase in the infiltration of intratumoral CD8 T cells as well as the mRNA levels of their IL10 receptor α (IL10Rα). The antitumor effects of targeting Aurora-A were attenuated in the absence of CD8 T cells. In addition, antibody-mediated blockade of IL10Rα dramatically decreased the percentage of intratumoral CD8 T cells. In further experiments, we found that the levels of IL10 were elevated in the serum of azoxymethane/dextran sodium sulfate-treated mice. Unexpectedly, we found that in addition to Aurora-A's mitotic role, inhibition of Aurora-A elevated IL10 transcription, which in turn increased the IL10Rα mRNA levels in CD8 T cells. Thus, inhibition of Aurora-A could be a useful treatment strategy for recruiting tumor-specific intratumoral CD8 T cells. IMPLICATIONS: Understanding the mechanisms by which inhibition of Aurora-A promotes CD8 T-cell infiltration and activation, as mediated by the IL10 pathway could provide a potential strategy for tumor immunotherapy.