EZH2 and in situ carcinoma: Furthermore, it has been demonstrated that actinic keratosis and cSCC tissue have significantly increased EZH2 expression in comparison to normal skin: the highest percentage of EZH2 expression has been reported in the early stage of the disease for carcinomas in situ, and lower percentages in the invasive carcinoma stage with poor differentiation, possibly due to loss of nuclei and less immunohistochemical staining (39).