STATs: An Old Story, Yet Mesmerizing

Signal transducers and activators of transcription (STATs) are cytoplasmic transcriptionfactors that have a key role in cell fate. STATs, a protein family comprised ofseven members, are proteins which are latent cytoplasmic transcription factors thatconvey signals from the cell surface to the nucleus through activation by cytokinesand growth factors. The signaling pathways have diverse biological functions thatinclude roles in cell differentiation, proliferation, development, apoptosis, and inflammationwhich place them at the center of a very active area of research. In this reviewwe explain Janus kinase (JAK)/STAT signaling and focus on STAT3, which istransient from cytoplasm to nucleus after phosphorylation. This procedure controlsfundamental biological processes by regulating nuclear genes controlling cell proliferation,survival, and development. In some hematopoietic disorders and cancers,overexpression and activation of STAT3 result in high proliferation, suppression ofcell differentiation and inhibition of cell maturation. This article focuses on STAT3and its role in malignancy, in addition to the role of microRNAs (miRNAs) on STAT3activation in certain cancers.