Effect of Aurora kinase B on polyploidy and decidualization in mouse uterus

RESEARCH QUESTION

Decidualization is critical to the establishment of mouse normal pregnancy. The fibroblast-like stromal cells in the process form polyploid multinucleated cells. Aurora kinase B (Aurora B) has previously been shown to regulate polyploidy in various cells. However, whether Aurora B regulates the formation of decidual cell polyploidization and its regulatory mechanisms remain poorly understood.

DESIGN

Establish decidualization model of mouse primary endometrial stromal cells in vitro. Construct pseudopregnancy mouse models and delayed-activation mouse models. Detect Aurora B and polyploidization related genes in mouse uteri treated by Aurora B specific inhibitor Barasertib and CPT.

RESULTS

In this study, we found that Aurora B was strongly expressed in endometrial stromal cells after implantation. Additionally, Aurora B was remarkably up regulated in the stromal cells of oil-induced deciduomoa and in vitro decidualization. As an Aurora B specific inhibitor, Barasertib significantly inhibits the mRNA expression of Prl8a2, a marker of mouse decidualization. Furthermore, the protein levels of p-Plk1, Survivin and p-Cdk1 were inhibited by Barasertib. CPT-induced DNA damage suppressed Aurkb (encodes Aurora B) expression, thus resulting in polyploidization.

CONCLUSION

Our data shows that Aurora B is expressed in decidual stromal cells of implantation sites and plays a key role for mouse decidualization. The protein of Plk1, Survivn, and Cdk1 may participate in formation of decidual cell polyploidization during mouse decidualization.

Promising effects of exosomes from menstrual blood-derived mesenchymal stem cells on endometriosis

Endometriosis as a non-malignant gynecological disease leads to dysregulation of numerous cellular functions including apoptosis, angiogenesis, migration, proliferation, and inflammation. Accumulating evidence has shed light on the importance of endometrial stem cells within the menstrual blood which are involved in the establishment and progression of endometriotic lesions in a retrograde manner. According to the fact that the therapeutic benefits of mesenchymal stem cells are provided through paracrine functions, we used exosomes from menstrual blood-derived stem cells (MenSCs) for treating endometriotic stem cells to inhibit their lesion formation tendency. Menstrual blood samples from healthy and endometriosis women were collected. Isolated MenSCs by the density-gradient centrifugation method were characterized by flow cytometry. Secreted exosomes were isolated from healthy MenSCs (NE-MenSCs) and used to treat endometriotic cells (E-MenSCs). 72 h after treatment, different mechanisms and pathways including inflammation, proliferation, apoptosis, migration, and angiogenesis were analyzed using Real-Time PCR, ELISA, immunocytochemistry, annexin V/PI, and scratching assay. Exosome treatment significantly reduce the expression level of markers related to inflammation, proliferation, migration, and angiogenesis in E-MenSCs which are aberrantly expressed in endometriosis. Moreover, apoptosis was induced in E-MenSCs after treatment which was evaluated in both gene and protein levels. In this study, we give preliminary evidence for the potential of MenSCs-Exo in ameliorating endometriosis. Regarding our results, we suggest that after relevant clinical trial, MenSCs-derived exosomes can be considered as a better treatment option to improve endometriosis compared to common and conventional treatments and show their potential as a cell-free product in endometriosis repair.

Iron overload inhibits cell proliferation and promotes autophagy via PARP1/SIRT1 signaling in endometriosis and adenomyosis

Emerging evidence suggests that excess iron accumulates in endometriotic and adenomyotic lesions. However, the role iron overload plays in the pathogenesis of endometriosis or adenomyosis remains unknown. Primary human eutopic endometrial stromal cells (EuESCs) from endometriosis or adenomyosis patients were used as the in vitro model of endometriosis or adenomyosis in this study. We found that iron, manifesting as ferric ammonium citrate (FAC; 0.05-4.8 mM), significantly inhibited cell growth, induced oxidative stress through the Fenton reaction, and functionally activated autophagy in EuESCs, as measured by 5-ethynyl-2'-deoxyuridine incorporation assay, MitoSOX™ Red staining, LC3 turnover assay, and tandem mCherry-eGFP-LC3B fluorescence microscopy. Immunohistochemistry analysis of Ki67 expression in proliferative-phase endometrial tissues revealed that cell proliferation in ectopic tissues was dramatically compromised, suggesting that iron overload may play a role in cell growth inhibition in vivo. We observed that autophagy may alleviate the FAC-induced inhibition of endometrial stromal cell proliferation. Furthermore, sequential FAC (0.8 mM, 24 h) and hydrogen peroxide (H₂O₂; 300 μM, 2 h) treatment successfully induced the Fenton reaction in EuESCs and caused extensive apoptosis, whereas the disruption of autophagy by the knockdown of BECN1 further aggravated cell death. MitoSOX™ Red staining showed that autophagy may promote the survival of EuESCs by decreasing of the Fenton reaction-induced reactive oxygen species generation. In addition, we observed that the Fenton reaction-induced oxidative stress significantly suppressed iron overload-induced autophagy. Moreover, we found that FAC treatment impaired poly(ADP-ribose)-polymerase 1 (PARP1) expression while simultaneously upregulating SIRT1 expression in EuESCs. Our data further showed that PARP1 expression decreased in endometriotic lesions, which may partially result from iron overload. We also found that PARP1 inhibition aggravated iron overload-induced cell growth suppression, and was implicated in iron overload-induced autophagy. In addition, SIRT1 silencing alleviated iron overload-induced PARP1 downregulation and autophagy activation. Overall, our data suggest that iron overload in endometrial stromal cells of endometriotic or adenomyotic lesions may be involved in the inhibition of cell proliferation, simultaneously with the activation of protective autophagy via PARP1/SIRT1 signaling.

Effects of Aurora kinase A on mouse decidualization via Stat3-plk1-cdk1 pathway

BACKGROUND

Decidualization is essential to the successful pregnancy in mice. The molecular mechanisms and effects of Aurora kinase A (Aurora A) remain poorly understood during pregnancy. This study is the first to investigate the expression and role of Aurora A during mouse decidualization.

METHODS

Quantitative real time polymerase chain reaction, western blotting and in situ hybridization were used to determine the expression of Aurora A in mouse uteri. Aurora A activity was inhibited by Aurora A inhibitor to explore the role of Aurora A on decidualization via regulating the Aurora A/Stat3/Plk1/Cdk1 signaling pathway.

RESULTS

Aurora A was strongly expressed at implantation sites compared with inter-implantation sites. Furthermore, Aurora A was also significantly increased in oil-induced deciduoma compared with control. Both Aurora A mRNA and protein were significantly increased under in vitro decidualization. Under in vitro decidualization, Prl8a2, a marker of mouse decidualization, was significantly decreased by TC-S 7010, an Aurora A inhibitor. Additionally, Prl8a2 was reduced by Stat3 inhibitor, Plk1 inhibitor and Cdk1 inhibitor, respectively. Moreover, the protein levels of p-Stat3, p-Plk1 and p-Cdk1 were suppressed by TC-S 7010. The protein levels of p-Stat3, p-Plk1 and p-Cdk1 were also suppressed by S3I-201, a Stat3 inhibitor). SBE 13 HCl (Plk1 inhibitor) could reduce the protein levels of p-Plk1 and p-Cdk1. Collectively, Aurora A could regulate Stat3/Plk1/Cdk1 signaling pathway.

CONCLUSION

Our study shows that Aurora A is expressed in decidual cells and should be important for mouse decidualization. Aurora A/Stat3/Plk1/Cdk1 signaling pathway may be involved in mouse decidualization.

TFEB, SIRT1, CARM1, Beclin-1 expression and PITX2 methylation in breast cancer chemoresistance: a retrospective study

BACKGROUND

Breast cancer chemoresistance is attributed to a wide variety of mechanisms, including autophagy. Transcription factor EB (TFEB) has been recently identified and characterized as one major regulator of autophagy and lysosomal genesis.

OBJECTIVE

This study aims to evaluate the prognostic impact of TFEB and its pathway in breast cancer chemoresistance.

METHODS

This retrospective study analyzes the expression of TFEB, CARM1, SIRT1, and Beclin-1 and the methylation of PITX2 in breast carcinoma. A group of breast cancer patients treated with chemotherapy, who relapsed within 12 months from treatment initiation, were compared to a sub-cohort of chemo-treated patients who did not recur within 12 months of follow-up. The expression of TFEB, CARM1, SIRT1, and Belcin-1 was analyzed using immunohistochemistry or RT-PCR on formalin-fixed paraffin-embedded samples. PITX2 methylation was tested with the diagnostic CE-marked kit Therascreen PITX2 RGQ PCR. In the final model, 136 cases of chemo-treated breast cancer were included.

RESULTS

A higher TFEB and Beclin-1 expression correlate with shorter survival in patients with chemo-treated invasive breast cancer (respectively HR 3.46, CI.95 1.27-9.47, p < 0.05 and 7.11, CI.95 2.54-19.9). TFEB, CARM1, and SIRT1 are positively correlated with Beclin-1. The protein expression of SIRT1 is significantly associated with TFEB and CARM1 so that a very low SIRT1 expression (lower than the first quartile of the H-score distribution) correlates with a low expression of TFEB and CARM1 and with longer survival. SIRT1 seems to have a lower H-score in the basal-like and HER2-enriched tumors than the luminal subtypes. Beclin-1 and TFEB seem to have a higher H-score in the basal-like and HER2-enriched tumors than the luminal subtypes. PITX2 methylation analysis was feasible only in 65% of the selected samples, but no significant differences between cases and controls were found, and there was also no correlation with the expression of the TFEB pathway.

CONCLUSIONS

TFEB, SIRT1, and Beclin-1 seem to have a potential prognostic significance in patients with chemo-treated breast cancer, likely because of their role in the regulation of autophagy. In addition, no correlation between TFEB and PITX2 methylation was found, likely because they perform two different roles within the autophagy process.

Insights into molecular pathways of endometriosis and endometriosis-related ovarian carcinoma

Background: Endometriosis is a benign estrogen-dependent gynecological disease involving components of the female genital tract (uterus, Fallopian tubes, ovaries, large, round, and utero-sacral ligaments) and intra- and extraperitoneal regions. Since the moment of its etiopathogeny has been identified, the intrinsic capacity of endometriosis malignant transformation has been hypothesized. Patients,Materials and Methods: Our study included a total number of 50 patients diagnosed with endometriosis (31 cases) and endometriosis-related ovarian carcinoma (EOC) (19 cases). A clinicopathological and immunohistochemical study directed towards the detection of atypical transition lesions and the similitudes in epithelial–mesenchymal transition (EMT) phenomenon [E-cadherin/β-catenin/cytokeratin 18 (CK18)], apoptosis [B-cell lymphoma 2 (Bcl-2)/Bcl-2-associated X (Bax)], and hormonal dynamics mirrored by the immunoexpression of estrogen receptor (ER) and progesterone receptor (PR) in endometriosis and EOC glands and stroma has been performed. Results: Our study showed a higher immunoexpression of CK18 and E-cadherin in endometriosis than in neoplastic counterparts, while β-catenin had a stronger immunoexpression in tumors compared with endometriotic areas, with statistically significant differences between the studied groups. Bcl-2/Bax higher rate in endometriosis had a statistically significant association to a more aggressive tumor behavior (p=0.020). ER immunoexpression was stronger in endometriosis, with less negative scores compared to EOC, while PR immunoexpression was stronger in endometriosis, with a lower percent of negative scores compared to EOC. PR immunostaining was correlated to ovarian location of endometriosis (p=0.004) and tumor grade of EOC (p=0.027). Stromal ER and PR immunoexpression has been significantly lower in endometriosis in comparison to tumor stroma (p=0.001) and PR stromal immunoexpression had been higher in more differentiated tumors compared to less differentiated types (p=0.005). Conclusions: Our study supports that endometriosis is a precursor of EOC by the identification and the coexistence of both lesions in the investigated cases, the identification of intermediate lesions, as well as the expression of EMT immunomarkers, along with apoptosis and steroid receptors immunoexpression.

Human Endometriosis Tissue Microarray Reveals Site-specific Expression of Estrogen Receptors, Progesterone Receptor, and Ki67

Most available therapies for endometriosis are hormone-based and generally broadly used without taking into consideration the ovarian hormone receptor expression status. This contrasts strikingly with the standard of care for other hormone-based conditions such as breast cancer. We therefore aimed to characterize the expression of ovarian steroid hormone receptors for estrogen alpha (ESR1), estrogen beta (ESR2), and progesterone (PGR) in different types of endometriotic lesions and eutopic endometrium from women with endometriosis and controls using a tissue microarray (TMA). Nuclear expression levels of the receptors were analyzed by tissue (ie, ectopic vs. eutopic endometrium) and cell type (ie, glands vs. stroma). Ovarian lesions showed the lowest expression of ESR1 and PGR, and the highest expression of ESR2, whereas the fallopian tube lesions showed high expression of the 3 receptors. Differences among endometria included lower expression of ESR1 and higher expression of ESR2 in stroma of proliferative endometrium from patients versus patients, and a trend towards loss of PGR nuclear positivity in proliferative endometrium from patients. The largest ESR2:ESR1 ratios were observed in ovarian lesions and secretory endometrium. The highest proportion of samples with >10% Ki67 positive nuclei was in glands of fallopian tube (54%) and extrapelvic lesions (75%); 60% of glands of secretory endometrium from patients had >10% Ki67 positivity compared with only 15% in controls. Our results provide a better understanding of endometriosis heterogeneity by revealing lesion type-specific differences and case-by-case variability in the expression of ovarian hormone receptors. This knowledge could potentially predict individual responses to hormone therapies, and set the basis for the application of personalized medicine approaches for women with endometriosis.

Common and specific gene signatures among three different endometriosis subtypes

Aims

To identify the common and specific molecular mechanisms of three well-defined subtypes of endometriosis (EMs): ovarian endometriosis (OE), peritoneal endometriosis (PE), and deep infiltrating endometriosis (DIE).

Methods

Four microarray datasets: GSE7305 and GSE7307 for OE, E-MTAB-694 for PE, and GSE25628 for DIE were downloaded from public databases and conducted to compare ectopic lesions (EC) with eutopic endometrium (EU) from EMs patients. Differentially expressed genes (DEGs) identified by limma package were divided into two parts: common DEGs among three subtypes and specific DEGs in each subtype, both of which were subsequently performed with the Kyoto Encyclopedia of Genes (KEGG) pathway enrichment analysis. The protein-protein interaction (PPI) network was constructed by common DEGs and five hub genes were screened out from the PPI network. Besides, these five hub genes together with selected interested pathway-related genes were further validated in an independent OE RNA-sequencing dataset GSE105764.

Results

A total of 54 EC samples from three EMs subtypes (OE, PE, DIE) and 58 EU samples were analyzed, from which we obtained 148 common DEGs among three subtypes, and 729 specific DEGs in OE, 777 specific DEGs in PE and 36 specific DEGs in DIE. The most enriched pathway of 148 shared DEGs was arachidonic acid (AA) metabolism, in which most genes were up-regulated in EC, indicating inflammation was the most common pathogenesis of three subtypes. Besides, five hub genes AURKB, RRM2, DTL, CCNB1, CCNB2 identified from the PPI network constructed by 148 shared DEGs were all associated with cell cycle and mitosis, and down-regulated in EC, suggesting a slow and controlled proliferation in ectopic lesions. The KEGG pathway analysis of specific DEGs in each subtype revealed that abnormal ovarian steroidogenesis was a prominent feature in OE; OE and DIE seems to be at more risk of malignant development since both of their specific DEGs were enriched in the pathways in cancer, though enriched genes were different, while PE tended to be more associated with dysregulated peritoneal immune and inflammatory microenvironment.

Conclusion

By integrated bioinformatic analysis, we explored common and specific molecular signatures among different subtypes of endometriosis: activated arachidonic acid (AA) metabolism-related inflammatory process and a slow and controlled proliferation in ectopic lesions were common features in OE, PE and DIE; OE and DIE seemed to be at more risk of malignant development while PE tended to be more associated with dysregulated peritoneal immune and inflammatory microenvironment, all of which could deepen our perception of endometriosis.

Functional expression of aryl hydrocarbon receptor on mast cells populating human endometriotic tissues

Endometriosis is an inflammatory disease characterized by the presence of ectopic endometrial tissue outside the uterus. A diffuse infiltration of mast cells (MCs) is observed throughout endometriotic lesions, but little is known about how these cells contribute to the network of molecules that modulate the growth of ectopic endometrial implants and promote endometriosis-associated inflammation. The aryl hydrocarbon receptor (AhR), a transcription factor known to respond to environmental toxins and endogenous compounds, is present in MCs. In response to AhR activation, MCs produce IL-17 and reactive oxygen species, highlighting the potential impact of AhR ligands on inflammation via MCs. Here, we investigated the possibility that endometrial MCs promote an inflammatory microenvironment by sensing AhR ligands, thus sustaining endometriosis development. Using human endometriotic tissue (ET) samples, we performed the following experiments: (i) examined the cytokine expression profile; (ii) counted AhR-expressing MCs; (iii) verified the phenotype of AhR-expressing MCs to establish whether MCs have a tolerogenic (IL-10-positive) or inflammatory (IL-17-positive) phenotype; (iv) measured the presence of AhR ligands (tryptophan-derived kynurenine) and tryptophan-metabolizing enzymes (indoleamine 2,3-dioxygenase 1 (IDO1)); (v) treated ET organ cultures with an AhR antagonist in vitro to measure changes in the cytokine milieu; and (vi) measured the growth of endometrial stromal cells cultured with AhR-activated MC-conditioned medium. We found that ET tissue was conducive to cytokine production, orchestrating chronic inflammation and a population of AhR-expressing MCs that are both IL-17 and IL-10-positive. ET was rich in IDO1 and the AhR-ligand kynurenine compared with control tissue, possibly promoting MC activation through AhR. ET was susceptible to treatment with an AhR antagonist, and endometrial stromal cell growth was improved in the presence of soluble factors released by MCs on AhR activation. These results suggest a new mechanistic role of MCs in the pathogenesis of endometriosis.

Endometrial biomarkers for the non-invasive diagnosis of endometriosis

BACKGROUND

About 10% of reproductive-aged women suffer from endometriosis, which is a costly, chronic disease that causes pelvic pain and subfertility. Laparoscopy is the gold standard diagnostic test for endometriosis, but it is expensive and carries surgical risks. Currently, there are no non-invasive tests available in clinical practice that accurately diagnose endometriosis. This is the first diagnostic test accuracy review of endometrial biomarkers for endometriosis that utilises Cochrane methodologies, providing an update on the rapidly expanding literature in this field.

OBJECTIVES

To determine the diagnostic accuracy of the endometrial biomarkers for pelvic endometriosis, using a surgical diagnosis as the reference standard. We evaluated the tests as replacement tests for diagnostic surgery and as triage tests to inform decisions to undertake surgery for endometriosis.

SEARCH METHODS

We did not restrict the searches to particular study designs, language or publication dates. To identify trials, we searched the following databases: CENTRAL (2015, July), MEDLINE (inception to May 2015), EMBASE (inception to May 2015), CINAHL (inception to April 2015), PsycINFO (inception to April 2015), Web of Science (inception to April 2015), LILACS (inception to April 2015), OAIster (inception to April 2015), TRIP (inception to April 2015) and ClinicalTrials.gov (inception to April 2015). We searched DARE and PubMed databases up to April 2015 to identify reviews and guidelines as sources of references to potentially relevant studies. We also performed searches for papers recently published and not yet indexed in the major databases. The search strategies incorporated words in the title, abstract, text words across the record and the medical subject headings (MeSH).

SELECTION CRITERIA

We considered published peer-reviewed, randomised controlled or cross-sectional studies of any size that included prospectively collected samples from any population of reproductive-aged women suspected of having one or more of the following target conditions: ovarian, peritoneal or deep infiltrating endometriosis (DIE).

DATA COLLECTION AND ANALYSIS

Two authors independently extracted data from each study and performed a quality assessment. For each endometrial diagnostic test, we classified the data as positive or negative for the surgical detection of endometriosis and calculated the estimates of sensitivity and specificity. We considered two or more tests evaluated in the same cohort as separate data sets. We used the bivariate model to obtain pooled estimates of sensitivity and specificity whenever sufficient data were available. The predetermined criteria for a clinically useful test to replace diagnostic surgery was one with a sensitivity of 94% and a specificity of 79%. The criteria for triage tests were set at sensitivity at or above 95% and specificity at or above 50%, which in case of negative results rules out the diagnosis (SnOUT test) or sensitivity at or above 50% with specificity at or above 95%, which in case of positive result rules in the diagnosis (SpIN test).

MAIN RESULTS

We included 54 studies involving 2729 participants, most of which were of poor methodological quality. The studies evaluated endometrial biomarkers either in specific phases of the menstrual cycle or outside of it, and the studies tested the biomarkers either in menstrual fluid, in whole endometrial tissue or in separate endometrial components. Twenty-seven studies evaluated the diagnostic performance of 22 endometrial biomarkers for endometriosis. These were angiogenesis and growth factors (PROK-1), cell-adhesion molecules (integrins α3β1, α4β1, β1 and α6), DNA-repair molecules (hTERT), endometrial and mitochondrial proteome, hormonal markers (CYP19, 17βHSD2, ER-α, ER-β), inflammatory markers (IL-1R2), myogenic markers (caldesmon, CALD-1), neural markers (PGP 9.5, VIP, CGRP, SP, NPY, NF) and tumour markers (CA-125). Most of these biomarkers were assessed in single studies, whilst only data for PGP 9.5 and CYP19 were available for meta-analysis. These two biomarkers demonstrated significant diversity for the diagnostic estimates between the studies; however, the data were too limited to reliably determine the sources of heterogeneity. The mean sensitivities and specificities of PGP 9.5 (7 studies, 361 women) were 0.96 (95% confidence interval (CI) 0.91 to 1.00) and 0.86 (95% CI 0.70 to 1.00), after excluding one outlier study, and for CYP19 (8 studies, 444 women), they were were 0.77 (95% CI 0.70 to 0.85) and 0.74 (95% CI 0.65 to 84), respectively. We could not statistically evaluate other biomarkers in a meaningful way. An additional 31 studies evaluated 77 biomarkers that showed no evidence of differences in expression levels between the groups of women with and without endometriosis.

AUTHORS' CONCLUSIONS

We could not statistically evaluate most of the biomarkers assessed in this review in a meaningful way. In view of the low quality of most of the included studies, the findings of this review should be interpreted with caution. Although PGP 9.5 met the criteria for a replacement test, it demonstrated considerable inter study heterogeneity in diagnostic estimates, the source of which could not be determined. Several endometrial biomarkers, such as endometrial proteome, 17βHSD2, IL-1R2, caldesmon and other neural markers (VIP, CGRP, SP, NPY and combination of VIP, PGP 9.5 and SP) showed promising evidence of diagnostic accuracy, but there was insufficient or poor quality evidence for any clinical recommendations. Laparoscopy remains the gold standard for the diagnosis of endometriosis, and using any non-invasive tests should only be undertaken in a research setting. We have also identified a number of biomarkers that demonstrated no diagnostic value for endometriosis. We recommend that researchers direct future studies towards biomarkers with high diagnostic potential in good quality diagnostic studies.

Correlation Between the Clinical Parameters and Tissue Phenotype in Patients Affected by Deep-Infiltrating Endometriosis

The current study aimed to identify and validate an applicable immunohistochemistry panel including Ki-67, c-MYC, estrogen receptor-α (ER-α), and progesterone receptor isoforms A/B (PR-A/B) in correlation with clinicopathological parameters in patients affected by deep infiltrating endometriosis. Tissue microarrays were prepared from a cohort of 113 patients. Phenotypic profile of the panel molecules was evaluated in glands and stroma in parallel with microvessels and stroma density measurements. Principal component analysis was performed on 8 immunohistochemical variables, 2 histological variables, and 8 subgroups of clinical parameters. The immunohistochemical profiling showed consistent Ki-67 immunostaining in 17.9% of the samples and c-MYC in 83.1%, while intense ER-α immunoreactivity was detected in 84% of the samples and PR-A/B isoforms in 24.1% of them. The combination of clinical parameters and tissue phenotype allowed a stratification of endometriosis-affected patients. Such novel phenotypical and clinical correlation could be helpful in the future studies for a better stratification of the disease aiming at a personalized patient care.

Immunohistochemical Analysis of the Effect of Dienogest on Ovarian Endometriotic Cysts

Dienogest is a novel progestin with potent oral progestational activity that inhibits the clinical symptoms of endometriosis. We herein evaluated the effect of dienogest on ovarian endometriotic cysts via immunohistochemistry. Ovarian endometriotic cyst specimens were collected from 12 patients treated with dienogest and 20 patients not treated with hormones (controls). The expression of estrogen receptor (ER)-α, progesterone receptor A (PRA), and Ki-67 was studied by immunohistochemistry. As compared with the controls, the cell proliferation index was significantly reduced in both epithelial and stromal cells of the endometriotic cysts following the use of dienogest (P = 0.022 and P = 0.004, respectively). However, there was no significant difference between endometriotic cysts with and without the use of dienogest in the expressions of ER-α and PRA in the epithelial and stromal cells. Irrespective of the use of dienogest, the expression levels of ER-α and PRA in the epithelial cells were low (median: 32% and 8%, respectively). Conversely, the expression levels of ER-α and PRA in the stromal cells were well preserved (median: 68% and 92%, respectively). In the controls, there was no significant difference between endometriotic cysts in the expression levels of Ki-67, ER-α and PRA in epithelial and stromal cells during the proliferative and secretory phases. The finding of a reduction in the cell proliferation index by the use of dienogest with no change in the expressions of hormonal receptors may not support the direct progestational effect of dienogest on ovarian endometriotic cysts.

Inhibition of adhesion, proliferation, and invasion of primary endometriosis and endometrial stromal and ovarian carcinoma cells by a nonhyaluronan adhesion barrier gel

Endometriosis is a chronic disease of women in the reproductive age, defined as endometrial cells growing outside of the uterine cavity and associated with relapses. Relapses are hypothesized to correlate with incomplete surgical excision or result from nonrandom implantation of new endometrial implants in adjacent peritoneum. Thus, surgical excision could lead to free endometriotic cells or tissue residues, which readhere, grow, and invade into recurrent lesions. Barrier agents are frequently used to prevent postoperative adhesions. We tested if the absorbable cell adhesion barrier gel Intercoat consisting of polyethylene oxide and sodium carboxymethyl cellulose could inhibit cellular adhesion, proliferation, and invasion of primary endometriosis and endometrial cells. Due to an association of endometriosis with ovarian carcinoma, we tested two ovarian carcinoma cell lines. Prior to cell seeding, a drop of the barrier gel was placed in cell culture wells in order to test inhibition of adherence and proliferation or coated over a polymerized collagen gel to assay for prevention of invasion. Results showed that the barrier gel significantly inhibited cell adherence, proliferation, and invasion of endometriosis and endometrial stromal cells as well as ovarian carcinoma cells in culture. Our findings could help to prevent local cell growth/invasion and possible consequent recurrences.

The relationship among HOXA10, estrogen receptor α, progesterone receptor, and progesterone receptor B proteins in rectosigmoid endometriosis: a tissue microarray study

BACKGROUND

Very few studies have evaluated the expression of homeobox A10 (HOXA10) and steroid (estrogen and progesterone) receptors exclusively in deep endometriosis. Conclusions drawn from studies evaluating peritoneal and ovarian endometriosis are usually generalized to explain the pathogenesis of the disease as a whole. We aimed to evaluate the expression of HOXA10, estrogen receptor α (ER-α), progesterone receptor (PR), and PR-B in rectosigmoid endometriosis (RE), a typical model of deep disease.

METHODS

We used RE samples from 18 consecutive patients to construct tissue microarray blocks. Nine patients each were operated during the proliferative and secretory phases of the menstrual cycle. We quantified the expressions of proteins by immunohistochemistry using the modified Allred score.

RESULT

The HOXA10 was expressed in the stroma of nodules during the secretory phase in 5 of the 18 patients. Expression of ER-α (in 16 of 18 patients), PR (in 17 of 18 patients), and PR-B (17 of 18 patients) was moderate to strong in the glands and stroma of nodules during both phases. Expression of both PR (P = .023) and PR-B (P = .024) was significantly greater during the secretory phase.

CONCLUSION

The HOXA10 is expressed in RE, where it likely imparts the de novo identity of endometriotic lesions. The ER-α, PR, and PR-B are strongly expressed in RE, which differs from previous studies investigating peritoneal and ovarian lesions. This suggests different routes of pathogenesis for each of the 3 types of endometriosis.

A potential link of oxidative stress and cell cycle regulation for development of endometriosis

BACKGROUND

The roles of molecular alteration such as genomic instability and cell survival are debated aspects of the pathogenesis of endometriosis. To review the contemporary literature on potential factors and their signaling pathways that support prolonged survival of endometriotic cells.

METHODS

This article reviews the English-language literature for molecular, pathogenetic, and pathophysiological studies on endometriosis. This review is focused on the association of hepatocyte nuclear factor (HNF)-1β with endometriosis.

RESULTS

The iron-induced oxidative stress plays a fundamental role for the pathogenesis of endometriosis. Oxidative stress, secondary to influx of iron during retrograde menstruation, modifies lipids and proteins, leading to cell and DNA damage. Recent studies demonstrated HNF-1β overexpression in endometriotic foci. HNF-1β increases the survival of endometriotic cells under iron-induced oxidative stress conditions possibly through the activation of forkhead box (FOX) transcription factors and/or endometriosis-specific expression of microRNAs. Endometriotic cells expressing HNF-1β also display cell cycle checkpoint pathways required to survive DNA damaging events.

CONCLUSIONS

HNF-1β in endometriosis might be a factor that controls the cell cycle and DNA damage checkpoints.

Tissue remodeling and nonendometrium-like menstrual cycling are hallmarks of peritoneal endometriosis lesions

We identified differentially expressed genes comparing peritoneal endometriosis lesions (n = 18), eutopic endometrium (n = 17), and peritoneum (n = 22) from the same patients with complete menstrual cycles using microarrays (54 675 probe sets) and immunohistochemistry. Peritoneal lesions and peritoneum demonstrated 3901 and 4973 significantly differentially expressed genes compared to eutopic endometrium, respectively. Peritoneal lesions significantly revealed no correlation with a specific menstrual cycle phase by gene expression and histopathology, exhibited low expressed proliferation genes, and constant levels of steroid hormone receptor genes. Tissue remodeling genes in cytoskeleton, smooth muscle contraction, cellular adhesion, tight junctions, and O-glycan biosynthesis were the most significant to lesions, including desmin and smooth muscle myosin heavy chain 11. Protein expression and location of desmin, alpha-actin, and h-caldesmon in peritoneal lesions discriminated between smooth muscle hyperplasia and metaplasia. Peritoneal lesions demonstrate no menstrual cycle phasing but constant steroid hormone receptor expression where a slow but steady growth is linked with tissue remodeling. Our study contributes to the molecular pathology of peritoneal endometriosis and will help to identify clinical targets for treatment and management.