CD274 and breast cancer: Considering that coactivator TAZ, a component of the Hippo signaling pathway, is reported to transcriptionally activate PD‐L1 by interacting with the transcription factor TEAD to promote tumor immune escape in lung and breast cancer,[21] and transcriptional coactivator MRTF‐A interacts with NF‐κB/p65 to activate the transcription of PD‐L1 in non‐small‐cell lung cancer (NSCLC) cells,[22] it is interesting to know whether the transcription coactivator SRC‐1 is a key orchestrator that also transcriptionally activates PD‐L1.