These negative feedback regulators include phosphatases (DUSPs), which inactivate MAP kinases (Fritsche‐Guenther et al, 2011); RNA binding proteins, which mediate degradation of IEGs (e.g. ZFP36, which binds FOS mRNA); and other negative feedback elements, such as tumour suppressors (Amit et al, 2007). This evidence concerns the gene FOS and neoplasm.