PLK1 and sarcoma: Our analysis of sarcoma data in TCGA by GEPIA showed that high levels of CDK1, KIF11, AURKB, MAD2L1, BUB1B and CCNB2 (Fig. 4a–f) were strongly related to worse OS (P = 0.0063, 0.0023, 0.0036, 0.018, 0.0032 and 0.017, respectively), whereas the four other hub genes (PLK1, NDC80, CCNB1, CDC20) demonstrated no significant association (Fig. 4g–j).