To answer the question whether or not HPV infection results in a switch of SOX expression, we studied the association between the topographic localization of SOX17 and SOX2 expressing epithelia and the viral infection as detected by p16 and ISH, using 23 cases of SIL that could be studied in detail (Table 2). The gene discussed is SOX2; the disease is squamous cell intraepithelial neoplasia.