Increased visfatin expression has been shown to increase gene expression, which promotes cell survival and increases SirT1 activity thereby promoting angiogenesis. Previous studies have shown that oral squamous cell carcinomas (OSCCs) express high levels of activated signal transducer and activator of transcription 3 (Stat3). Since visfatin expression is increased by Stat3, we hypothesized that visfatin protein may be highly expressed in OSCCs. Immunohistochemistry was the technique used to examine the expression of visfatin in 19 OSCCs and 4 hyperplastic lesions. The results indicated that visfatin was detected in the cytoplasm and nuclei of the OSCCs and epithelial hyperplasia as well as in the stromal tissues of patients with OSCC and oral hyperplasia. Furthermore, co-expression of visfatin and proliferating cell nuclear antigen proteins was noted in verrucous epithelial hyperplasia, and co-expression of visfatin and CD68 in the inflammatory cells of the stromal region was noted in the OSCCs. In addition, enzyme-linked immunosorbent assay showed that plasma visfatin concentrations were significantly increased in the patients with OSCC and oral hyperplasia compared to those of the control subjects. In conclusion, visfatin expression and concentrations were higher in OSCCs and oral hyperplasia, suggesting that visfatin may play a role in the pathogenesis of oral cancers.
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