Overexpression of CRM1 has been observed in several cancers, and it has been identified as the major nuclear exporter for several onco­proteins, growth regulators and suppressor proteins such as p53, p21, BRCA1/2, Rb and FOXO, which lead to the initiation and progression of cancer (Hill et al., 2014 ▸; Faustino et al., 2007 ▸; Turner et al., 2012 ▸; Watt & Leaner, 2010 ▸). The gene discussed is RB1; the disease is cancer.