Human papillomavirus DNA and p53 status in penile carcinomas.
Our study aimed at evaluating the presence of human papillomavirus (HPV) DNA in a series of 84 paraffin-embedded (PET) penile carcinomas. We have also investigated the presence of p53 mutations in these tumors by immunohistochemistry (IHC), single-stranded conformational polymorphism (SSCP) and DNA sequencing. Tissues were submitted to amplification of a 268 bp fragment from the beta-globin gene and a fragment of the E6 gene of HPV types 6, 11, 16 and 18. Twenty samples (18 fixed in Bouin's solution and 2 in buffered formalin) were found inadequate and were excluded from the analysis. In the remaining 64 tumors, HPV DNA was found in 26% of the samples. The prevalence of HPV in fresh samples of the same tumors was 56%. The most prevalent type was HPV 16 in both fresh samples and PET. Isotopic in situ hybridization was performed in all PET samples, but only 2 cases were positive, 1 for HPV 16 and 1 for HPV 18. Immunohistochemistry with anti-p53 pAb 1801 antibody showed a positive nuclear reaction over more than 5% of tumor cells in 26% of the cases. SSCP of exons 5-8 of the p53 gene was performed on 9 HPV-positive and 12 HPV-negative specimens. Abnormal mobility was found in 26% of the tumors, of which 2 were HPV-positive and 5 HPV-negative. Point mutations were detected in p53 exons 6 (1 case), 7 (1 case) and 8 (5 cases), showing that high-risk type HPVs and mutated p53 may coexist in these tumors. Our data indicate that a subset of penile carcinomas are etiologically related to HPV and that an overlapping subset may arise from mutational events in the p53 gene.
Levi
J E
JE
Ludwig Institute for Cancer Research, São Paulo Branch, Brazil.
Rahal
P
P
Sarkis
A S
AS
Villa
L
L
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D004279:DNA, Viral / Q000032:analysis*; D016158:Genes, p53; D006801:Humans; D008297:Male; D008875:Middle Aged; D027383:Papillomaviridae / Q000235:genetics*; D010412:Penile Neoplasms / Q000235:genetics / Q000821:virology*; D016133:Polymerase Chain Reaction; D016159:Tumor Suppressor Protein p53 / Q000032:analysis
D004279:DNA, Viral; D016159:Tumor Suppressor Protein p53