CD274 and cancer: Recently, Shibata’s team found that H2O2 could upregulate PD-L1 expression in cancer cells and prompt the depletion of BER enzymes, particularly DNA glycosylases, such as NTH1, OGG1 and NEIL1, which significantly augments PD-L1 upregulation in response to H2O2 by activating ATR/Chk1 signaling at the DNA replication fork collapse, resulting in cytotoxic DNA damage [123].