CD274 and neoplasm: Regarding the expression of immune checkpoint molecules, Treg in ascites showed increased expression of PD-1 (42.45 ± 8.02% of Treg) and PD-L1 (30.75 ± 10.84% of Treg), whereas the proportions of tumor-infiltrated PD-1+ Treg and PD-L1+ Treg were 18.30 ± 5.64% and 36.57 ± 15.48%, respectively (Figure 4H).