The cytoplasmic events that control mammalian gene expression, primarily mRNA 
stability and translation, potently influence the cellular response to internal 
and external signals. The ubiquitous RNA-binding protein (RBP) HuR is one of the 
best-studied regulators of cytoplasmic mRNA fate. Through its 
post-transcriptional influence on specific target mRNAs, HuR can alter the 
cellular response to proliferative, stress, apoptotic, differentiation, 
senescence, inflammatory and immune stimuli. In light of its central role in 
important cellular functions, HuR's role in diseases in which these responses 
are aberrant is increasingly appreciated. Here, we review the mechanisms that 
control HuR function, its influence on target mRNAs, and how impairment in 
HuR-governed gene expression programs impact upon different disease processes. 
We focus on HuR's well-recognized implication in cancer and chronic 
inflammation, and discuss emerging studies linking HuR to cardiovascular, 
neurological, and muscular pathologies. We also discuss the progress, potential, 
and challenges of targeting HuR therapeutically.