Lack of EVER2 Protein in Two Epidermodysplasia Verruciformis Patients with Skin Cancer Presenting Previously Unreported Homozygous Genetic Deletions in the EVER2 Gene

Epidermodysplasia verruciformis (EV) is a rare, lifelong, autosomal recessive skin disease (OMIM number 226400) associated with an unusual susceptibility to infections with ubiquitous beta human papillomaviruses (β-HPVs), but not to infections with other pathogens, including cutaneous and genital HPVs of the alpha, gamma, mu, or nu genera (Jablonska and Majewski, 1994; Orth, 2006). β-HPVs are evolutionarily distinct from the other HPV genera and are associated with widespread in-apparent or asymptomatic infections in the general population (Bernard et al., 2010; Bravo et al., 2010). In immunosuppressed individuals, however, and in individuals suffering from the rare inherited disease EV, these viruses can replicate unchecked and have been implicated in the development of non-melanoma skin cancer (Akgul et al., 2006; Bouwes Bavinck et al., 2011; Proby et al., 2011). The sensitivity of EV patients to β-HPVs has been linked to homozygous mutations in two genes (EVER1 and EVER2; Ramoz et al., 2002). The mutation of either of the EVER genes holds the potential to alleviate EVER-mediated host restriction and favor β-HPV replication and skin carcinogenesis, as is the case in EV patients (Lazarczyk et al., 2009). In this report, we describe the presence of two previously unreported homozygous mutations in the EVER2 gene in two Italian EV patients, each of whom have already developed more than 10 non-melanoma skin cancer.