LAUSR

In recent years, an increasing number of reports have linked the RNA‐binding protein Staufen1 (STAU1) to the control of cell decision making. In non‐transformed cells, STAU1 balances the expression of messenger RNA (mRNA) regulons that regulate differentiation and well‐ordered cell division. Misregulation of STAU1 expression and/or functions changes the fragile balance in the expression of pro‐ and anti‐proliferative and apoptotic genes and favours a novel equilibrium that supports cell proliferation and cancer development. The misregulation of STAU1 functions causes multiple coordinated modest effects in the post‐transcriptional regulation of many RNA targets that code for cell cycle regulators, leading to dramatic consequences at the cellular level. The new tumorigenic equilibrium in STAU1‐mediated gene regulation observed in cancer cells can be further altered by a slight increase in STAU1 expression that favours expression of pro‐apoptotic genes and cell death. The STAU1‐dependent cell cycle regulon is a good model to study how abnormal expression of an RNA‐binding protein promotes cell growth and provides an advantageous selection of malignant cells in the first step of cancer development.