FIGURE 3

Representative nonisotopic in situ hybridization analysis. A, punctate (type 2) signal in Caski cells (arrows). B, diffuse (type 1) in an oral hyperplasia infected by human papillomavirus 6. C, punctate (type 2) signal in an oral squamous cell carcinoma infected by human papillomavirus 16 (arrows) (original magnification, ×1000). Diaminobenzidine used as chromogen.