Abstract
Neoplastic or cancer stem cells (CSCs) are tumor cells which are able to mimic phenotypic and functional features of adult stem cells, such as self-renewal and multilineage potential. In addition, CSCs are resistent to the majority of xenobiotics (including classic antineoplastic drugs) since they present low proliferative index and express efflux pumps (such as Pgp and ABCG2). These char…