Prostaglandin D-2 synthase (PTGDS), also known as a glutathione-independent prostaglandin D synthase, catalyzes prostaglandin H-2 to prostaglandin D-2 that exhibits functions that include regulation of the central nervous system, contraction/relaxation of smooth muscle and inhibition of platelet aggregation. Gene profiling data based on our previous study indicated that PTGDS is significantly increased during development, differentiation and remodeling of the oviduct in chickens in response to estrogen. Therefore, the aims of the present study were to investigate expression of PTGDS in the oviduct and examine if the relationship between PTGDS and estrogen is conserved during development and remodeling of the oviduct. Results of our study indicated that PTGDS expression is specifically localized to the luminal (LE) and glandular epithelial (GE) cells of the chicken oviduct in response to diethylstilbestrol, a synthetic estrogen. In addition, PTGDS expression increased during the regeneration phase of the oviduct in concert with increasing concentrations of estrogen in the circulation of laying hens during induced molting. Moreover, PTGDS mRNA and protein were expressed abundantly in GE of ovarian carcinoma, but not in normal ovaries. These results provide the first evidence that PTGDS is a novel estrogen-stimulated gene in oviductal epithelial cells, as well as a candidate biomarker for diagnosis of ovarian carcinoma. (C) 2014 Elsevier Inc. All rights reserved.