PDCD1 and cancer: Altogether, this dual effect of DDRi-induced immune activation and PD-L1-dependent immunosuppression suggests immunologic vulnerability that may be exploited through the use of ICI, and serves as the rationale for studies investigating the clinical efficacy of combination therapy with PARPi’s and anti-PD-1/PD-L1 in multiple cancers, including TNBC (121, 128).