Augmented cell survival in eutopic endometrium from women with endometriosis: Expression of c-myc, TGF-beta1 and bax genes

BACKGROUND: Endometriosis is a common gynaecological disorder characterized by the presence of endometrial tissue outside of the uterus. The fragments in normal menstruation are composed of necrotic and living cells, which do not survive in ectopic locations because of programmed cell death. The aim of this study was to evaluate if the balance between cell proliferation and apoptosis is changed in eutopic endometrium from women with endometriosis throughout the menstrual cycle by studying bax (pro-apoptotic), c-myc (regulator of cell cycle) and TGF-beta1 (involved in cell differentiation) genes. METHODS: Eutopic endometrium was obtained from: 30 women with endometriosis (32.8 +/- 5 years) and 34 fertile eumenorrheic women (36 +/- 5.3 years). We analyzed apoptosis (TUNEL: DNA fragmentation); cell proliferation (immunohistochemistry (IHC) for Ki67); c-myc, bax and TGF-beta1 mRNA abundance (RT-PCR) and TGF-beta1 protein (IHC) in endometrial explants. RESULTS: Cell proliferation strongly decreased from proliferative to late secretory phases in glands, but not in stroma, in both endometria. Positive staining in glands and stroma from proliferative endometrium with endometriosis was 1.9- and 2.2-fold higher than control endometrium, respectively (p < 0.05). Abundance of c-myc mRNA was 65% higher in proliferative endometrium from endometriosis than normal tissue (p < 0.05). TGF-beta1 (mRNA and protein) augmented during mid secretory phase in normal endometrium, effect not observed in endometrium with endometriosis. In normal endometrium, the percentage of apoptotic epithelial and stromal cells increased more than 30-fold during late secretory phase. In contrast, in endometrium from endometriosis, not only this increase was not observed, besides bax mRNA decreased 63% versus normal endometrium (p < 0.05). At once, in early secretory phase, apoptotic stromal cells increased 10-fold with a concomitant augment of bax mRNA abundance (42%) in endometria from endometriosis (p < 0.05). CONCLUSION: An altered expression of c-myc, TGF-beta1 and bax was observed in eutopic endometrium from endometriosis, suggesting its participation in the regulation of cell survival in this disease. The augmented cell viability in eutopic endometrium from these patients as a consequence of a reduction in cell death by apoptosis, and also an increase in cell proliferation indicates that this condition may facilitate the invasive feature of the endometrium

P450Arom induction in isolated control endometrial cells by peritoneal fluid from women with endometriosis

Objective: To study the effect of peritoneal fluid from women with (PF-E) and without (PF-C) endometriosis on P450Arom expression in endometrial cells. Design: Experimental study. Setting: University research unit. Patient(s): Forty women of reproductive age with (n ¼ 22) or without (control; n ¼ 18) endometriosis. Intervention(s): Peritoneal fluid and eutopic endometrial samples were obtained during surgery from women with (n ¼ 13 and 9, respectively) and without (n ¼ 4 and 14, respectively) endometriosis. Main Outcome Measure(s): Expression study for P450Arom, steroid factor 1 (SF-1), chicken ovalbumin upstream transcription factor I (COUP-TFI), and COUP-TFII messenger RNA (reverse transcriptase–polymerase chain reacion) and/or protein (immunoblot) in isolated endometrial epithelial cells transfected or not with expression vector containing SF-1, COUP-TFI, or COUP-TFII complementary DNAs. Result(s): Basal messenger RNA and/or protein expression of P450Arom and SF-1 were augmented in endometriosis, and that of COUP-TF was diminished. In control cells, (Bu)2cAMP and PF-E increased P450Arom and SF-1 expression (but not COUP-TF expression) in a dose-dependent way, an effect not observed with PF-C, adsorbed PF-E, or 10 5 M indomethacin. Transfected cells confirmed these results. Any treatments modified the studied molecules in endometriosis cells. Conclusion(s): These data indicate that molecules contained in PF-E favor an estrogenic microenvironment, suggesting a role in the etiopathogenesis of endometriosis enabling the survival, maintenance, and growth of endometrial implants in the ectopic locations

Association between MMP1 and MMP9 activities and ICAM1 cleavage induced by tumor necrosis factor in stromal cell cultures from eutopic endometria of women with endometriosis

Endometriosis is a benign gynecological pathology in which immune system deregulation may play a role in its initiation and progression. In endometriotic lesions, intercellular adhesion molecule-1 (ICAM1) is released from the cell membrane by proteolytic cleavage of its extracellular domain, a process that coincides with increased expression and proteolytic activity of metalloproteinases such as MMP1 and MMP9. The objective of our study was to investigate the association between MMP1 and MMP9 activities and ICAM1 cleavage mediated by tumor necrosis factor (TNF) in eutopic endometrial stromal cells from women with and without (control) endometriosis during culture. The RNA was evaluated by RT-PCR, and the protein was determined by western blot (ICAM1, MMP1), casein or gelatin zymographies (secreted active MMP1 or MMP9 respectively), ELISA (soluble ICAM1 (sICAM1)), and fluorescence assay (secreted active MMP1). Under basal conditions, proMMP9 dimer and MMP9 were higher in endometriosis

Nuclear factor κB pathway and interleukin-6 are affected in eutopic endometrium of women with endometriosis

In order to investigate the role of the nuclear factor κB (NFKB) pathway on gene expression in the eutopic endometrium in endometriosis, and in particular of interleukin-6 (IL6), we evaluated RELA, IκB kinase (CHUK), NFKBIA and IL6 expressions and NFKB DNA binding in eutopic endometrium from women with endometriosis. Eutopic endometrium was obtained from 37 women with endometriosis and 42 fertile women during laparoscopy. We analysed RELA, CHUK, NFKBIA and IL6 mRNA levels (RT-PCR); RELA, CHUK and NFKBIA proteins and p-NFKBIA/NFKBIA ratio (western blot); and NFKB binding (DNA shift assay) and IL6 concentration (ELISA) in endometrial explants. Our results indicate that mRNA and cytoplasmic proteins of RELA and CHUK exhibit constant levels in normal endometrium during the menstrual cycle. A dramatic increase (P&lt;0.05) in NFKBIA mRNA expression, RELA nuclear presence and the mRNA and the protein of IL6 during late secretory phase was also observed in this tissue. By contrast, in eutopic en

Differential expression of upstream stimulatory factor (USF) 2 variants in eutopic endometria from women with endometriosis: estradiol regulation

BACKGROUND: Endometriosis, pro-inflammatory and invasive benign disease estrogen dependent, abnormally express in endometria the enzyme P450Arom, positively regulated by steroid factor-1 (SF-1). Our objective was to study the nuclear protein contents of upstream stimulating factor 2 (USF2a and USF2b), a positive regulator of SF-1, throughout the menstrual cycle in eutopic endometria from women with and without (control) endometriosis and the involvement of nuclear estrogen receptors (ER) and G-coupled protein estrogen receptor (GPER)-1 RESULTS: Upstream stimulating factor 2 protein contents were higher in mid (USF2b) and late (USF2a and USF2b) secretory phase in eutopic endometria from endometriosis than control (p < 0.05). In isolated control epithelial cells incubated with E2 and PGE2, to resemble the endometriosis condition, the data showed: (a) significant increase of USF2a and USF2b nuclear protein contents when treated with E2, PPT (specific agonist for ERa) or G1 (specific agonist for GPER1); (b) no increase in USF2 binding to SF-1 E-Box/DNA consensus sequence in E2-treated cells; (c) USF2 variants protein contents were not modified by PGE2; (d) SF-1 nuclear protein content was significantly higher than basal when treated with PGE2, E2 or G1, stimulation unaffected by ICI (nuclear ER antagonist); and (e) increased (p < 0.05) cytosolic protein contents of P450Arom when treated with PGE2, E2, PPT or G1 compared to basal, effect that was additive with E2 + PGE2 together. Nevertheless, in endometriosis cells, the high USF2, SF-1 and P450Arom protein contents in basal condition were unmodified CONCLUSION: These data strongly suggest that USF2 variants and P450Arom are regulated by E2 through ERa and GPER1, whereas SF-1 through GPER1, visualized by the response of the cells obtained from control endometria, being unaffected the endogenously stimulated cells from endometriosis origin. The lack of E2 stimulation on USF2/SF-1 E-Box/DNA-sequence binding and the absence of PGE2 effect on USF2 variants opposite to the strong induction that they exert on SF1 and P450 proteins suggest different mechanisms and indirect regulations. The sustained USF2 variants protein expression during the secretory phase in eutopic endometria from women with endometriosis may participate in the pathophysiology of this disease strongly associated with infertility and its characteristic endometrial invasion to ectopic sites in the pelvic cavit