Similarities between 16E7-grafts and HPV-infected anogenital neoplasias identified by immunohistochemistry.
(A) Both PCNA and MCM7 displayed similar ectopic expression in most suprabasal cells of 16E7-grafts. In the basal layer, areas of expression coexisted with expression-free areas. (B) The same patterns were observed in tumor areas of cervical carcinoma samples where p16 was also present. PCNA and MCM7 expression expands progressively upwards in CIN1 and CIN3 (C), while most basal and subrabasal cells were stained in different cases of bowenoid papulosis (D). Middle panels in C and inserts in D highlight areas of basal cells showing negative staining for MCM7, PCNA and p16 (the latter, in CIN1). Dotted lines indicate the location of the basal membrane.