The potential of cell therapy in regenerative medicine has greatly expanded thanks to the availability of sources of pluripotent cells. In particular, induced pluripotent stem cells (iPS) have dominated the scenario in the last years for their ability to proliferate and differentiate into specific cell types. Nevertheless, the concerns inherent to the cell reprogramming process, limit iPS use in therapy and pose questions on the long-term behavior of these cells. In particular, despite the development of virus-free methods for their obtainment, a major and persisting drawback, is related to the acquisition of a stable pluripotent state, that is un-physiological and may lead to cell instability. The increased understanding of epigenetic mechanisms has paved the way to the use of "small molecules" and "epigenetic modifiers" that allow the fine tuning of cell genotype and phenotype. In particular, it was demonstrated that an adult mature cell could be directly converted into a different cell type with the use of these chemicals, obtaining a new patient-specific cell, suitable for cell therapy. This approach is simple and direct and may represent a very promising tool for the regenerative medicine of several and diverse degenerative diseases.
Keywords: Cell conversion; Epigenetic memory; Regenerative medicine; Reprogramming; Trans-differentiation.