Abstract
Abstract: :
Purpose: Since heat shock proteins (hsp) are used as stimulators of tumor vaccination and their expression is of prognostic significance in several tumors, we determined the expression of heat shock proteins 27, 70, 90 and glycoprotein (gp) 96 in uveal melanoma. We also investigated whether hsp expression was associated with known prognostic parameters. Methods: Expression of hsp27, hsp70, hsp90 and gp96 was determined on formalin-fixed and paraffin-embedded sections of 20 uveal melanomas by immunohistochemistry (alkaline phosphatase anti-phosphatase staining) with specific monoclonal antibodies, and scored semi-quantitavely. Results: Expression of the different hsps on uveal melanomas was variable. We noted expression of hsp27 in all uveal melanomas with 30 to 100% (average 74%) of cells stained. Hsp70 and hsp90 were expressed in less than 10% of cells in respectively 80% and 55% of uveal melanomas. Expression of gp96 occured in 90% (0-100%, average 59% of cells) of uveal melanomas. The percentage of heat shock protein expression did not correlate significantly with known prognostic factors (largest basal tumor diameter, mitotic rate, or cell type). Conclusion: Expression of heat shock proteins is not correlated with known prognostic factors in uveal melanomas. The high expression of gp96 on 90% of uveal melanomas indicates, however, that this protein could be used as a potential trigger in tumor vaccination.
Keywords: 464 melanoma • 496 oncology • 434 immunohistochemistry