CD8A and cancer: Moreover, PDSs linked to low PD-L1 expression were enriched for proteins associated with immunosuppressive TME and T cell exclusion such as VCAN1, FHL1, MYH11, LTC4S and AOC3, and efficient CD8+ T cell expansion and effector function such as Caveolin-1 (CAV1), suggesting two scenarios within the primary cancer with low T cell infiltration or an effective cytotoxic T cell infiltration and response36,45–53.