Expression of αB-crystallin and its potential anti-apoptotic role in oral verrucous carcinoma

Abstract

αB-crystallin, a member of the small heat shock protein family, acts as a molecular chaperone. αB-crystallin has been found to be overexpressed in a number of cancer tissues, including head and neck cancers. Overexpression of αB-crystallin in cancer tissue may be related to its anti-apoptotic properties; however, its mechanism of action remains unclear. The aim of this study was to investigate the anti-apoptotic role of αB-crystallin in oral verrucous carcinoma (OVC). Since oral squamous cell carcinoma (OSCC) is the most common tumor of the oral cavity, we selected OSCC as a control group. Immunohistochemical staining was used to evaluate the expression levels. The results showed that the expression of αB-crystallin was detected in OVC, OSCC and normal oral mucosa (NM). The expression in OVC was higher compared to that of NM, but lower compared to OSCC, indicating that OVC was less aggressive than OSCC with respect to malignancy potential. Furthermore, we found that in OVC, the increased expression of αB-crystallin coincided with the decreased expression of activated caspase-3. The results indicated that αB-crystallin may play an anti-apoptotic role via inhibition of the activation of caspase-3 in OVC.