Expression of αB-crystallin and vascular endothelial growth factor in conjunctival squamous cell carcinoma.

To examine the expression of αB-crystallin and vascular endothelial growth factor (VEGF) in conjunctival squamous cell carcinoma (CSCC). Seven CSCCs and three normal conjunctivas that were surgically excised were studied. Paraformaldehyde-fixed, paraffin-embedded tissue sections were processed for immunohistochemistry with antibodies against αB-crystallin, its phosphorylated forms, and VEGF. In vitro experiments were conducted to investigate the effects of mitomycin C (MMC) treatment on the expression of αB-crystallin and VEGF secretion. αB-Crystallin and VEGF were strongly expressed in CSCCs compared to normal conjunctivas. αB-Crystallin immunoreactivity was co-localized with that for VEGF in CSCCs, whereas these signals were reduced in CSCC tissues treated with MMC before excision. MMC treatment suppressed the αB-crystallin expression and VEGF secretion in cultured conjunctival cells in a dose-dependent manner. This study demonstrated αB-crystallin and VEGF expressions in human CSCCs, which may play a role in the pathogenesis. αB-Crystallin expression, and VEGF secretion were reduced by MMC, indicating a novel therapeutic mechanism in MMC treatment for human CSCC.