The present study investigated the expression of p8, a transcription factor upregulated in some human cancers, in oral squamous cell carcinomas (OSCCs). Immunohistochemical analysis of p8 expression was carried out on 20 archived surgical specimens of human OSCCs, and expression correlated with clinical outcome parameters in a retrospective study. Expression of p8 in a number of OSCC cell lines also was investigated by western blot and RT-PCR analyses. p8 was expressed in 80 % (16/20) of the samples with levels of expression exhibiting a significant difference (χ(2) = 8.352, df = 3, p = 0.039) by patient age. Furthermore, greater levels of p8 immunoreactivity was significantly associated with advanced tumor grade (p = 0.008). p8 also was upregulated in OSCC cell lines. p8 is expressed in a significant proportion of OSCCs, and in human OSCC cell lines, suggesting a potential value of p8 as a diagnostic and/prognostic tool for oral cancers.