title: Nanocarrier-mediated drugs targeting cancer stem cells: an emerging delivery approach.
abstract: BACKGROUND
  Cancer stem cells (CSCs) play an important role in the development of drug resistance, metastasis and recurrence. Current conventional therapies do not commonly target CSCs. Nanocarrier-based delivery systems targeting cancer cells have entered a new era of treatment, where specific targeting to CSCs may offer superior outcomes to efficient cancer therapies.
  
  
  METHODS
  This review discusses the involvement of CSCs in tumor progression and relevant mechanisms associated with CSCs resistance to conventional chemo- and radio-therapies. It highlights CSCs-targeted strategies that are either under evaluation or could be explored in the near future, with a focus on various nanocarrier-based delivery systems of drugs and nucleic acids to CSCs. Novel nanocarriers targeting CSCs are presented in a cancer-specific way to provide a current perspective on anti-CSCs therapeutics.
  
  
  CONCLUSIONS
  The field of CSCs-targeted therapeutics is still emerging with a few small molecules and macromolecules currently proving efficacy in clinical trials. However considering the complexities of CSCs and existing delivery difficulties in conventional anticancer therapies, CSC-specific delivery systems would face tremendous technical and clinical challenges. Nanocarrier-based approaches have demonstrated significant potential in specific drug delivery and targeting; their success in CSCs-targeted drug delivery would not only significantly enhance anticancer treatment but also address current difficulties associated with cancer resistance, metastasis and recurrence.
authors.affiliation: University of Manitoba, College of Pharmacy, Faculty of Health Sciences , 750 McDermot Avenue Winnipeg, MB R3E 0H5 , Canada.
authors.forename: Sarandeep
authors.initials: S
authors.lastname: Malhi
authors.forename: Xiaochen
authors.initials: X
authors.lastname: Gu
mesh_terms: D000818:Animals; D000970:Antineoplastic Agents / Q000008:administration & dosage*; D016503:Drug Delivery Systems; D019008:Drug Resistance, Neoplasm; D006801:Humans; D009369:Neoplasms / Q000188:drug therapy*; D014411:Neoplastic Stem Cells / Q000378:metabolism*
chemical_list: D000970:Antineoplastic Agents
keywords: anti-cancer stem cell therapeutics; cancer stem cells; drug delivery; nanocarriers; tumor resistance