Fig. 4

Immunostaining patterns of p16^INK4a, p53, and ki-67. A p16^INK4a positive control; B p16^INK4a negative control; C penile cancer showing score 1 for p16^INK4a; D Score 2 for p16^INK4a; E Score 3 for p16^INK4a; F p53 positive control; G p53 negative control; H PC showing no p53 expression; I 40% of tumor cells immunostained for p53; J 90% of tumor cells immunostained for p53; (K) tonsil used as ki-67 positive control; L tonsil with no ki-67 antibody applied and used as the negative control; M 20% of cells immunostained for ki-67; N 40% of cells immunostained for ki-67; O 90% of cells immunostained for ki-67. Magnification 100x (A-O)