Additionally, breast cancer cells in the hypoxic TME upregulate the expression of activating transcription factor 4 (ATF4), a member of the ATF/cAMP response element‐binding protein (CREB) family, which has been reported to be related to the recruitment of macrophages and promotion of angiogenesis which indirectly support tumor growth.23 The gene discussed is ATF4; the disease is breast carcinoma.