To examine the effects of the immRNA 3p10LA9 (Figure 2a) on breast cancer cells, we transfected RBCEVs with immRNA using REG1 and incubated the immRNA‐loaded RBCEVs with the highly metastatic mouse breast cancer 4T1 cells for 24 h. The gene discussed is ZC3H12A; the disease is breast carcinoma.