CD44 and breast neoplasm: designed a dual-molecule liposome loaded with doxorubicin and DNA aptamers for the differentiation and targeting of breast tumor cell spheroids and CSCs; one aptamer targets the surface marker mucin 1 antigen (MUC1; a transmembrane glycoprotein) on breast tumor cells, while the other targets the CSC marker glycoprotein CD44 antigen (379).