Expression and regulation of growth-regulated oncogene alpha in human endometrial stromal cells

Growth-regulated oncogene alpha (GROalpha), a potent chemoattractant for neutrophils, has previously been detected in the endometrial stromal cells (ESC) of human endometrium. In this study, the mRNA expression of GROalpha in the endometrium was evaluated by reverse transcription-polymerase chain reaction analysis, while the localization of GROalpha protein was studied by immunohistochemistry and the concentrations of GROalpha were measured using an enzyme-linked immunosorbent assay (ELISA). The effects of known modulators of endometrial function on the production of GROalpha by ESC were also examined by ELISA and Northern blot analysis. The expression of both GROalpha mRNA and GROalpha protein was detected in the cycling endometrium. GROalpha protein was localized mainly in the stroma, and endometrial tissues in the secretory phase contained higher amounts of GROalpha protein than did those in the proliferative phase. The production of GROalpha by ESC was enhanced by in-vitro decidualization. Lipopolysaccharide, tumour necrosis factor-alpha and interleukin-1beta also stimulated the expression of GROalpha mRNA and protein by ESC. These results suggest that the production of GROalpha by ESC is regulated by ovarian steroid hormones as well as by inflammatory mediators. The modulation of GROalpha concentrations in the local environment may contribute to normal and pathological processes in the uterus by regulating leukocyte trafficking in the endometrium.