CDKN2A and endometriosis: p16 labeling seemed colocalize with E-cadherin (glandular-epithelial cell marker), which was overexpressed in the epithelial compartment in samples from the non-endometriosis endometrium (Fig. 7a), eutopic endometrium (Fig. 7b), and deep infiltrative endometriosis groups (Fig. 7c).