Common chemotherapy is unable to eliminate the heterogeneous side population of cancer cells （such as cancer stem-like cells）, resulting in poor prognosis. The heterogeneity of cancer cells causes an extensive multidrug resistance through the aberrantly active Hedgehog （Hh） signaling pathway. Cyclopamine is a chemical compound that can block Hh signaling pathway, and a combination use of cyclopamine with anticancer drug would be beneficial for killing heterogeneous cancer cells. In the present study, we aimed to develop a kind type of fimctional drug liposomes for eliminating heterogeneous cancer, The study was performed on human breast cancer cells. A distearoylphosphoethanolamine polyethylene glycol （DSPE-PEG2000）-cyclopamine conjugate was newly synthesized by a nucleophilic substitution reaction, and confirmed by MALDI-TOF mass. An HPLC method was established and validated for qualification of epirubicin. Functional epimbicin liposomes were successful constructed by modifying with DSPE-PEG2o00-cyclopamine, displaying a particle size in nano-scale （approximately 98 nm） and a high epirubicin encapsulation （〉97%）. The CD44＋/CD24-side population was characterized in defining heterogeneous breast cancer cells. As compared with regular epirubicin liposomes, fimctional epirubicin liposomes exhibited an evidently enhanced cellular drug uptake and a significant killing effect in overall breast cancer cells. In conclusion, the functional epirubicin liposomes could be a useful drug delivery carrier for eliminating heterogeneous breast cancer cells.
