Li X, Sun G, Wu L, et al. - In breast cancer (BC) tissues, significant upregulation of ADAR (adenosine deaminase acting on RNA) was evident, which may encourage BC progression via the interaction of cancer cells, stromal cells, and immune cells. ADAR as a treatment target may offer new hope in breast cancer treatment.

• TCGA portal as well as UALCAN database and Tumor Immune Single-Cell Hub database were used to determine expression characteristics as well as role of ADAR gene in breast cancer.

• Significant upregulation of ADAR in BC tissues vs paracancerous tissues was seen, with its specific upregulation in cancer cell clusters and its expression in stromal and immune cell clusters.

• A positive correlation of ADAR upregulation with the clinicopathological stage as well as its negative correlation with BC prognosis was evident.

• Experimental processes in vitro showed ADAR knockdown hindered, proliferated, invaded, and migrated levels of BC cells.

• ADAR protein was primarily located in the nucleoli in cells and mainly implicated DNA modification and apoptotic signaling pathway.

• There may be interactions of immune factors with ADAR in BC, and there was a noticeable association of ADAR with immunosuppressors.