p63 in laryngeal squamous cell carcinoma: evidence for a role of TA-p63 down-regulation in tumorigenesis and lack of prognostic implications of p63 immunoreactivity.

p63 is a p53-related gene that encodes for multiple mRNA transcripts with (TA-p63) or without (DeltaN-p63) transactivating properties on p53-responsive genes. We evaluated for the first time the prevalence and clinical implications of p63 immunoreactivity (IR) and mRNA expression in laryngeal squamous cell carcinomas (LSCCs). Moreover, we also assessed the relationships between p63 expression and p53 gene status. p63 IR was detectable in the basal cell layers of non-neoplastic epithelium and in the whole thickness of dysplastic epithelium. All the 150 LSCCs analyzed were immunoreactive for p63, with 28 (18.7%) cases showing p63 IR in