Furthermore, we investigated the expression of PD‐L1 and CD47 in Human Protein Atlas (HPA) database, and found that the expressions of CD47 in breast tumour cells (MCF‐7, MDA‐MB‐231) were significantly higher than that in normal cells (HEK293, MCF‐10A), while PD‐L1 was only significantly expressed in MDA‐MB‐231 cells with high malignance (Figure S5A). Here, CD47 is linked to breast neoplasm.