CD274 and neoplasm: However, anti-PD-L1 treatment acted synergistically with Cxcl9 overexpression and significantly prolonged time to onset of ascites (median 51 vs. 45 days; P = 0.003) and overall survival (median 57 vs. 52 days; P = 0.007) in the Cxcl9+ tumour group (Fig. 2d).