Naciye Mulayim

Regulation of Fas Ligand Expression by Estradiol and Progesterone in Human Endometrium

Abstract Implantation involves a complex set of events, including apoptosis in endometrial cells. Apoptosis in human endometrium coincides with the implantation window, suggesting a potential role for steroid hormones in its regulation. Fas ligand (FasL) is one of the mediators of apoptosis in differentiated cells and in embryonic development. Interaction of FasL with its receptor, Fas, induces apoptosis through autocrine and paracrine signaling. We hypothesized that FasL expression in human endometrium is cycle-dependent and that sex steroid hormones regulate FasL expression. We first studied menstrual cycle-dependent expression of FasL in human endometrium by immunohistochemistry in 24 samples. We then investigated the in vitro regulation of FasL expression by ovarian steroid hormones. Throughout the menstrual cycle immunohistochemical staining intensity was stronger in the functional layer of endometrium than it was in the basal layer. FasL immunoreactivity increased gradually through the mid- and late-proliferative phases in both endometrial stromal and glandular cells. Strong FasL expression was observed throughout the late-proliferative and secretory phases. Semiquantitative reverse transcription-polymerase chain reaction analysis in cultured endometrial glandular cells demonstrated that estradiol and progesterone stimulate FasL mRNA expression. Western blot analysis in endometrial glandular and stromal cells in culture revealed that estradiol alone and in combination with progesterone up-regulated FasL protein expression. These results suggest that estradiol and progesterone may have a role in the regulation of maternal immunotolerance for the implantation of a semiallograft embryo by inducing FasL expression. We speculate that increased FasL expression may mediate the apoptosis of endometrial cells and thus may play a role in trophoblast invasion.

Elevated soluble Fas ligand levels may suggest a role for apoptosis in women with endometriosis.

OBJECTIVE To evaluate soluble Fas ligand concentrations in serum and peritoneal fluid from women with endometriosis and from fertile controls without endometriosis, and to study levels of soluble Fas ligand in conditioned media of cultured endometrial stromal cells. DESIGN Prospective, experimental trial. SETTING Two academic IVF centers. PATIENT(S) Twenty-nine fertile women without endometriosis and 57 infertile women with endometriosis (32 with stage I or II disease and 25 with stage III or IV disease). MAIN OUTCOME MEASURE(S) Enzyme-linked immunosorbent assay was used to measure soluble Fas ligand concentrations in paired samples of serum and peritoneal fluid from women with and without endometriosis. Concentrations were also measured in conditioned media of cultured endometrial stromal cells at basal conditions and after stimulation with interleukin-8 (0.001-10 ng/mL) and tumor necrosis factor-alpha (1-10 ng/mL). RESULT(S) Compared with fertile controls and women with early-stage of endometriosis, women with moderate to severe endometriosis had elevated serum (87.2 +/- 6.4, 88.2 +/- 6.9, and 162.3 +/- 7.8 pg/mL, respectively) and peritoneal fluid (81.0 +/- 6.0, 80.5 +/- 6.8, and 166.2 +/- 10.3 pg/mL, respectively) concentrations of soluble Fas ligand. Serum levels of soluble Fas ligand positively correlated with levels in peritoneal fluid. Comparison of patients in the same menstrual cycle in each group revealed that increased levels of soluble Fas ligand in patients with advanced endometriosis were not attributable to the difference in cycle phases. Soluble Fas ligand was not detected in conditioned media of endometrial stromal cells under baseline conditions or after stimulation. CONCLUSION(S) Serum and peritoneal fluid of women with moderate to severe endometriosis contain elevated concentrations of soluble Fas ligand compared to women with minimal or mild endometriosis and women without endometriosis. These findings suggest a role for apoptotic dysregulation in the pathophysiology of endometriosis.

Chemokine Receptor Expression in Human Endometrium

Abstract Chemokines play a role in endometrial physiology and pathology and may affect endometrial receptivity and menstrual shedding. Chemokines exert their effect by binding to their relevant receptors, the expression levels of which may modulate their action. In the present study, we examined the expression of chemokine receptors CXCR1 and CXCR2 (receptors for interleukin-8) and CCR5 (receptor for RANTES [regulated-on-activation, normal-T-cell-expressed and -secreted], macrophage inflammatory protein [MIP]-1α, and MIP-1β) in human endometrium. Human endometria (n = 35) were grouped according to the menstrual cycle phase and examined by immunohistochemistry for CXCR1, CXCR2, and CCR5. In both epithelial and stromal cells, CXCR1 and CXCR2 immunoreactivity was detected. Staining was most prominent at the apical and basal aspects of epithelial cells. Intense CCR5 immunostaining was observed in epithelial and stromal compartments throughout the menstrual cycle. Epithelial and stromal staining for CXCR1 reached a peak at the midsecretory phase, during which it was significantly higher than the level of staining during the proliferative phase (P < 0.05). Immunostaining for CXCR2 and CCR5 showed no significant variation across the menstrual cycle. Expression of interleukin-8 and RANTES in endometrium, together with the presence of their receptors, suggests that autocrine and paracrine interactions involving these chemokines may participate in endometrial physiology.

High concentrations of the CA-125, CA 19-9 and CA 15-3 in the peritoneal fluid between patients with and without endometriosis

ObjectiveIn the present study we compared the levels of CA-125, CA 19-9, and CA 15-3 in the peritoneal fluid (PF) of patients with and without endometriosis, then assessed the possibility of a correlation among these tumor markers.Study designOur study was a controlled clinical study of patients undergoing laparoscopy for infertility or other benign gynecology conditions. Peritoneal fluid samples were collected from 65 women with endometriosis and 43 women without pelvic disease. Levels of CA-125, CA 19-9 and CA 15-3 in the peritoneal fluid were determined by immunoradiometric assay.ResultsThe concentration of CA-125 in PF from patients with endometriosis was significantly higher than that in the control group (p<0.001); for CA 19-9 and CA 15-3, PF concentrations were not statistically different between these two groups. Women with endometriosis had significantly higher levels of CA-125 in proliferative and secretory phases than the control group (p<0.001 and p<0.002 respectively); furthermore, in patients with endometriosis the CA 19-9 levels were significantly lower in secretory phase than the proliferative (p<0.004). The levels of CA-125 were significantly lower in women with tubal ligation, in comparison with infertility or pelvic pain in the control group (p<0.001). No significant difference was seen in women with infertility or pelvic pain in endometriosis group and the levels of CA-125, CA 19-9, and CA 15-3. We did not find any correlation between the stages of endometriosis and the concentration of CA-125, CA 19-9 and CA 15-3. A significant correlation between the CA 19-9 levels and CA 15-3 in patients with endometriosis was found (r=0.72, p=0.001).ConclusionsWe found high concentrations of CA-125, CA 19-9, and CA 15-3 in the peritoneal fluid of women with and without endometriosis in the Yale series. However, the levels only of CA-125 were higher in women with endometriosis, but without diagnostic value. The role of simultaneously high concentrations of CA 19-9 and CA 15-3 in women with endometriosis needs to be explored further.