Expression of NY-ESO-1 cancer testis antigen in prostate cancer.

e16544Background: Poor outcomes in castrate resistant prostate cancer (CRPC) patients is a growing concern urging the need for innovative treatments. Cancer testis antigens (CTAs) like NY-ESO-1 are aberrantly expressed in several cancers including prostate cancer (PC). Given its tumor-restricted expression and ability to elicit spontaneous cytotoxic & antibody-mediated immune responses, NY-ESO-1 shows promise as an immunotherapy target. With the expertise of RPCI in NY-ESO-1 targeted therapeutics and limited information on NY-ESO-1 expression in CRPC, we sought this study. Methods: Immunohistochemical expression of NY-ESO-1 was analyzed in a series of PC samples from 2 different institutions. Two TMAs consisted of triplicate cores from 37 patients with localized PC (with cores from cancerous areas & the normal tissue adjacent to it), and 36 mCRPC patients. We also included 17 mCRPC whole sections for analyses. Intensity and percentage of NY-ESO-1 staining were recorded. The intensity was characterized as ...