Figure 4. Aurora kinase A inhibition in combination with PD-1 blockade extends the survival of HPV-positive tumor-bearing mice. (A–D) Groups of C57BL/6 mice were implanted with mEER cells (1×10⁶) subcutaneously on the flank and were treated sequentially with 10 mg/kg of alisertib and anti-PD-1 antibody (aPD-1) at 250 µg per dose individually or in combination (combo) as shown (A) and monitored for tumor growth (area) (B, C) and survival (D). Significant differences between the survival curves were determined using the log-rank Mantel-Cox test *p<0.05, **p<0.005, ***p<0.0005. (E–H) Tumor-infiltrating leukocytes were separated from tumors on day 23 after the tumor initiation when all the treatments were completed. Frequencies of total CD8 T cells (E), HPV E7 antigen-specific granzyme B-expressing (GrnzB⁺) CD8 T cells (F), regulatory T cells (FoxP3⁺) (G), and myeloid-derived suppressor cell (H) were measured using one-way analysis of variance. **p<0.005, ***p<0.0005. HPV, human papillomavirus; PD-1, programmed cell death protein-1.