Immunohistochemical analysis of breast cancer surgical specimens, coupled with bioinformatics analysis, demonstrated a significant correlation between MYC proto‐oncogene, bHLH transcription factor(c‐Myc)AIE photosensitizer expression and the stemness phenotype, as well as copper‐induced cytotoxicity, in breast cancer tissues. The gene discussed is MYC; the disease is breast carcinoma.