Stem cells as vehicles and targets of nanoparticles.

Modulation of endogenous adult stem cell niches represents a promising strategy for regeneration of tissues and to correct cell abnormalities, including cancer. Recent advances show the possibility to target endogenous stem cells or their progenies by using nanoparticles conjugated with specific biomolecules. In addition, the targeting of the stem cell niche can be accomplished by using stem cells loaded with nanoparticles. This review examines principles for the targeting of endogenous stem cells as well as factors for the modulation of stem cells.