In 2006,the group of Shinya Yamanaka demonstrated that somatic cells could be reprogrammed into induced pluripotent stem cells (iPSCs) by ectopic expression of four transcription factors associated to stemness:Oct4,Sox2,Klf4 and c-Myc [1].This groundbreaking discovery opened the possibility of generating patient-specific cells for research,drug development and regenerative medicine.Due to the tremendous potential of its clinical applications,understanding the process of reprogramming has become a priority and one of the most fascinating biomedical research topics.