Details on breast cancer cell lines and culture conditions are presented in the Supplementary material. TRA-8 antibody (mouse IgG1 isotype) was prepared at the University of Alabama at Birmingham [15 (link)]. Doxorubicin was obtained from Polymed Therapeutics (Houston, TX). Paclitaxel was from Sigma Aldrich Chemical Co. (St. Louis, MO). Abraxane was from the University of Alabama at Birmingham Hospital Pharmacy.