Immunohistochemical analysis of Caspase 14 in Tissue sections of human cervix. Samples were incubated in Caspase 14 polyclonal antibody (Product # PA5-72903) using a dilution of 1:2000. A. Normal cervix (squamous epithelium). B. CIN1 (low-grade squamous intraepithelial lesion, mild dysplasia). C. CIN2 (high-grade squamous intraepithelial lesion, moderate dysplasia. D. CIN3 (high-grade squamous intraepithelial lesion; severe dysplasia-carcinoma in situ. In normal cervi, caspase-14 staining was found most in the midzone layer, but was absent from the basal/parabasal cell layer where mitotically active cells are known to reside. This suggests induction of caspase-14 expression with differentiation. Caspase-14 expression declined progressively during malignant transformation as the histologic severity of the cervical atypia advanced from CIN1 to CIN3. Hematoxylin-eosin counterstain.