CTLA4 and ovarian cancer: The results showed that a significant positive correlation between SPP1 expression and immunoinhibitors, such as CD274 (PD-L1), CTLA4, LAG3 and TIGIT (Fig. 3H-3N, Supplementary table 3), suggesting that SPP1 expression were significantly associated with immune-checkpoint and SPP1 may play an important role in immune tolerance of ovarian cancer.