Detection of survivin mRNA in healthy oral mucosa, oral leucoplakia and oral cancer

Background: Survivin is involved in modulation of cell death and cell division processes. Survivin expression in normal adult tissues has not been fully understood, although it is markedly lower than in cancer, where it is over-expressed. Objective: To investigate survivin expression in normal, potentially malignant and cancerous oral mucosa. Methods: We measured survivin mRNA levels by real-time RT-PCR in specimens of oral mucosa (15 from normal mucosa, 17 from potentially malignant lesions, 17 from neoplasms). Scores were compared using Kruskal-Wallis test and post hoc according to Conover. Chi-squared test was used for dichotomous data. Results: The median relative levels of survivin mRNA resulted six for normal mucosa, eight for potentially malignant lesions, 13 for cancers: differences among these three groups were statistically significant, as between cancer and potentially malignant lesions. Expression in normal mucosa and potentially lesions group showed no significant difference. Low, but not marginal expression of survivin in normal mucosa is a new finding, and it could be explained with the higher sensibility of our methods. Conclusions: Survivin expression in oral potentially malignant lesions might indicate a progressive deregulation of expression paralleling oncogenesis, particularly during the first stages of process, suggesting a putative predictive role for survivin.