CD274 and breast cancer: Among the five samples with MMR loss for which PD-L1 was available, one (20%) had detectable PD-L1 ≥1; one of the three cyclin-dependent kinases 12 (CDK12) altered samples also had detectable PD-L1 ≥1 (33%), but none (0%) of the six breast cancer 2 (BRCA2) mutated mCRPC cases expressed PD-L1 (Fig. 3A).