Functional disturbance of p53 tumor suppressor protein contributes to uncontrolled cell growth. Human papillomavirus (HPV) E6 oncoproteins bind to wild-type p53 and abrogate its function. Our objective was to elucidate the relation of aberrant p53 protein expression to HPV DNA and cellular atypia in male genital warts and premalignant lesions. Immunohistochemically detectable p53 protein expression was studied in 35 male anogenital warts with low-level or no keratinocyte atypia (histologically confirmed condylomata acuminata), in 25 lesions with bowenoid papulosis (BP; carcinoma in situ) histology, and in 10 non-condyloma lesions using immunostaining with three established antibodies recognizing full-length wild-type accumulated p53 protein, or its conformational mutants. HPV DNA specific for HPV 6/11, 16/18, or 31/33/35 was identified by in situ hybridization or by polymerase chain reaction (PCR) - based amplification. Both nuclear and cytoplasmic keratinocyte immunostaining for p53 protein was detected in 41% of condylomata with no keratinocyte atypia and in 42% of condylomata with slight nuclear atypia or with bowenoid papulosis histology. No association of aberrant p53 expression with any specific HPV type or with HPV DNA was observed. Normal skin and some other penile dermatoses were negative for p53 immunostaining. In the follow-up biopsies of 16 BP patients, treated with CO2 laser, recurrence of atypia was seen exclusively in lesions initially positive for both HPV DNA and p53 protein. Our results show that a few cells in male genital warts even with no cellular atypia may express abnormally sequestered or loss-of-function p53 protein, and that concomitant presence of any type of HPV DNA is associated with recurrencies or progression of premalignant changes.
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