CD274 and neoplasm: MHC class I genes (HLA-A, HLA-B, HLA-C and B2M) and MHC class II genes (HLA-DRA and HLA-DRB1) were highly expressed in Cancer.cell.3, with upregulation in HRD relative to FBI adnexal tumours (Fig. 3f), indicative of increased antigen presentation accompanied by upregulated expression of CD274 (PD-L1) (Extended Data Fig. 8h; P = 2.8 × 10−3).