Insights into the Nanog gene: A propeller for stemness in primitive stem cells

Self-renewal and pluripotency are two major characteristics of embryonic stem cells (ESCs) that allow ESCs to maintain stem cell population, and differentiate into multiple types of adult tissues. Nanog is the key transcription factor that controls both self-renewal and pluripotency of ESCs. Similarly, cancer stem cells (CSCs) are capable of preserving population and initiating new tumor development by self-renewal. Expression of Nanog family proteins can be increased in many types of cancer which is correlated with tumor outcomes. In this review we summarized the recent understanding of the roles and mechanisms of Nanog in ESC regulation under physiological conditions. In addition, we describe the function of Nanog family proteins in different types of cancer, and the association of Nanog with clinical outcomes. Taken together, Nanog proteins are central regulators controlling both ESCs and CSCs, and are considered as a prognostic marker in many types of cancer. These findings supported the possibility of novel therapeutic potentials of Nanog against cancers.