MUC20 expression marks the receptive phase of the human endometrium (original) (raw)

Transmembrane and truncated (SEC) isoforms of MUC1 in the human endometrium and Fallopian tube

Reproductive Biology and Endocrinology, 2003

The cell surface mucin MUC1 is expressed by endometrial epithelial cells with increased abundance in the secretory phase of the menstrual cycle, when it is found both at the apical cell surface and in secretions. This suggests the presence of a maternal cell surface glycoprotein barrier to embryo implantation, arising from the anti-adhesive property of MUC1. In previous work, we demonstrated alternatively spliced MUC1 variant forms in tumour cells. The variant MUC1/SEC lacks the transmembrane and cytoplasmic sequences found in the full-length variant. We now show that MUC1/SEC mRNA is present in endometrial carcinoma cell lines, endometrial tissue and primary cultured endometrial epithelial cells. The protein can be detected using isoform-specific antibodies in uterine flushings, suggesting release from endometrium in vivo. However, on the basis of immunolocalisation studies, MUC1/SEC also remains associated with the apical epithelial surface both in tissue and in cultured cells. Transmembrane MUC1 and MUC1/SEC are both strikingly localised to the apical surface of tubal epithelium. Thus MUC1 may contribute to the anti-adhesive character of the tubal surface, inhibiting ectopic implantation. The mechanism by which this barrier is overcome in endometrium at implantation is the subject of ongoing investigation.

Expression of the transmembrane mucins, MUC1, MUC4 and MUC16, in normal endometrium and in endometriosis

Human reproduction (Oxford, England), 2014

Are the transmembrane mucins, MUC1, MUC4 and MUC16, differentially expressed in endometriosis compared with normal endometrium? This study revealed that transmembrane mucin expression does not vary significantly in normal endometrium during the menstrual cycle and is not altered in endometriosis relative to the epithelial marker, cytokeratin-18 (KRT18). Increased serum levels of the transmembrane mucin fragments MUC1, MUC4 and MUC16 that normally dominate the apical surface of simple epithelia are found in several pathological conditions, including endometriosis. Altered mucin expression in gynecologic diseases may promote infertility or endometrial pathologies. This was a laboratory-based study of samples from 12 endometriosis patients as well as non-endometriosis control samples obtained from 31 patients. Total RNA was isolated from endometrial biopsies of ectopic and eutopic endometrium from women with endometriosis and control patients from different stages of the menstrual cycl...

Genetic variations of MUC17 are associated with endometriosis development and related infertility

BMC Medical Genetics, 2015

Background: Genetic alterations of mucin genes, such as MUC2 and MUC4, were previously identified to be associated with endometriosis and related infertility. Additionally, gene expression profiling has confirmed MUC17 to be overexpressed in mucinous ovarian carcinoma; however, its associated risk for endometriosis remains unclear. This study was focused on the potential impact of genetic variations in MUC17 on endometriosis development and associated clinical features. Methods: The study subjects included 189 female Taiwanese patients with pathology-proven endometriosis and 191 healthy Taiwanese women as controls. Five single-nucleotide polymorphisms (rs4729645, rs10953316, rs74974199, rs4729655, and rs4729656) within the MUC17 gene were selected and genotyped using the Taqman genotyping assay to examine the allele frequency and genotype distributions of MUC17 polymorphisms. Results: Genotyping revealed that the A allele at rs10953316 in MUC17 was a protective genetic factor in endometriosis development (p = 0.008; OR = 0.53; 95 % CI: 0.36-0.79). Genetic variation of rs4729655 protected patients against endometriosis-induced infertility, but was associated with a higher cancer antigen 125 (CA125) level. Base-pairing analysis, called MaxExpect, predicted an additional loop in the mRNA structure caused by rs10953316 polymorphism, possibly influencing ribosome sliding and translation efficiency. Such predictions were confirmed by immunohistochemistry that patients with AA genotype at rs10953316 showed low MUC17 levels in their endometrium, patients with GA genotype showed moderate levels, and strong staining could be found in patients with GG genotype. Conclusions: MUC17 polymorphisms are involved in endometriosis development and the associated infertility in the Taiwanese population.

The expression of MUC1 in human Fallopian tube during the menstrual cycle and in ectopic pregnancy

Human Reproduction, 2009

background: Ectopic pregnancy is a major cause of maternal morbidity and mortality with increasing incidence worldwide. We have investigated whether epithelia from Fallopian tubes (FTs) bearing an ectopic pregnancy differ from normal tubes in expression of MUC1. methods: Since it is not possible to collect FTs from women carrying a healthy pregnancy, we studied tissue collected at the time of hysterectomy for benign disease. Women were injected with hCG in the days leading up to hysterectomy, and pseudopregnancy confirmed by the presence of high serum progesterone levels and the decidualization of the endometrium. FTs from the different stages of the menstrual cycle (n ¼ 24), tubes bearing an ectopic pregnancy (n ¼ 15) and pseudo-pregnant tubes (n ¼ 6) were collected and examined using immunohistochemistry and quantitative RT -PCR. results: MUC1 was present at the apical surface of the tubal epithelial cells throughout the menstrual cycle, but intracellular localization was minimal in the follicular phase, increasing to a maximum in the luteal phase. MUC1, including the glycoform recognized by antibody 214D4, was found at the apical surface of tubal epithelium in both the ectopic and pseudo-pregnant groups and the intracellular expression was much stronger in the pseudo-pregnant group than in the ectopic group. The 214D4 epitope was absent from tubal tissue adjacent to ectopic implants.

In vivo and in vitro studies of MUC1 regulation in sheep endometrium

In this study, we investigated the expression of mucin 1 (MUC1) mRNA and protein in sheep endometrium at different time points during follicular and luteal phases of estrous cycle, and also determined the effect of steroid hormone treatments and interferon tau (IFNs) on MUC1 mRNA expression in endometrial cell culture in vitro. In experiment one, 15 Welsh mountain ewes were synchronized to a common estrus and killed at precise stages of estrous cycle corresponding to (1) pre-LH peak, (2) LH peak, (3) post-LH peak, (4) early luteal, and (5) mid-luteal. Reproductive tracts were harvested and mRNA was extracted from the endometrial tissues. Parts of the uterine horns were fixed for immunohistochemistry. In experiment two, mixed populations of ovine endometrial cells (from slaughterhouse material collected at the postovulatory stage of the estrous cycle) were cultured to 70% confluence before treatment with (1) progesterone (P 4 , 10 ng/mL, for 48 hours), (2) estradiol (E 2 , 100 pg/mL, for 48 hours), or with (3) E 2 priming for 12 hours (100 pg/mL) followed by P 4 (10 ng/mL) for 36 hours. These were compared with: (4) IFNs (10 ng/mL, for 48 hours), and (5) basic medium (Dulbecco Modified Eagle Medium /F12) as control. The results showed that MUC1 mRNA and protein expression in sheep endometrium were highest during the midluteal stage and very low during the post-LH period compared with the other stages (P < 0.05). MUC1 immuno-staining in the luminal epithelium was apically restricted and was not significantly different across all stages of estrous cycle except at the post-LH peak where it was significantly low. In cell culture, MUC1 mRNA expression was significantly upregulated by both steroids either singly or in combination (P < 0.05), and downregulated in the presence of IFNs. In conclusion , endometrial MUC1 expression is cyclically regulated by both E 2 and P 4 in vivo and in vitro, and directly downregulated by IFNs treatment in vitro.

MUC1 as a Discriminator between Endometrium from Fertile and Infertile Patients with PCOS and Endometriosis

The Journal of Clinical Endocrinology & Metabolism, 2010

Context: Endometrium of fertile women expresses progesterone-regulated Mucin 1 (MUC1) that carries selectin ligands recognized by the human blastocyst. Altered MUC1 expression at the time of implantation may contribute to endometrial infertility. Objective: The aim was to assess the expression of MUC1 in the endometrium from polycystic ovary syndrome (PCOS), endometriosis, and fertile women in comparison with other hormone-regulated proteins [hydroxysteroid dehydrogenase (HSD) 1, HSD2, estrogen receptor (ER) and progesterone receptor (PR)]. Design and Patients: Endometrial samples were obtained from 33 fertile patients, 26 ovulatory PCOS patients, 15 anovulatory PCOS patients, and 25 endometriosis patients. Main Outcome Measure: Immunohistochemistry assessed the expression of MUC1 subunits ER, PR, HSD1, and HSD2 in endometrial epithelium. Endometrial MUC1 expression was quantified by immunoblots and RT-PCR. HSD1 and HSD2 expression was assayed by RT-PCR. Results: MUC1ND expression was significantly higher in ovulatory PCOS than in fertile and anovulatory PCOS patients, even after progesterone stimulation. MUC1ND and-CD expression was lower in anovulatory PCOS than in fertile patients. Only MUC1CD expression was lower in endometriosis patients. Endometrial ER expression was significantly higher in PCOS and endometriosis patients, whereas PR expression was significantly higher in PCOS than in fertile patients. The expression of HSD1 was significantly higher in anovulatory PCOS than in fertile patients. Expression of HSD2 was significantly higher in PCOS patients and lower in endometriosis patients. Conclusion: Expression of MUC1 subunits in the infertile endometrium is significantly different from fertile and appears to be a component of altered gene expression that potentially contributes to endometrial insufficiency.

Secrets of Endometrial Receptivity: Some Are Hidden in Uterine Secretome

American Journal of Reproductive Immunology, 2016

Endometrium, the innermost mucosal layer of the uterus, serves as a lodge for the embryo in eutherian mammals. The endometrium is constituted of various cell types, and each cell type executes specific functions to facilitate embryo implantation and development. It is well established that the endometrium, despite being non-permissive to the embryo for the major period of a menstrual cycle, is irreplaceable in the scheme of events essential for procreation. However, the embryo, before initiating physical contact with the endometrium, encounters the uterine cavity that remains bathed in uterine fluid. Uterine fluid is an admixture of endometrial secretions, plasma transudates, and oviductal fluid. Uterine fluid components are believed to play important roles in immunosuppression and embryo development during peri-implantation period. Uterine fluid is also involved in defense against pathogens, sperm migration, and lubrication of endometrium. The advent of highthroughput functional genomics tools has created enormous opportunities to investigate the uterine fluid for its protein repertoire and modulation during the receptive phase of an endometrial cycle in animals and humans. Towards this, few investigations have been conducted in recent years. The data obtained using non-targetted functional genomics approaches need to be assimilated with the existing information on specific components of uterine fluid.

Decreased MUC1 in endometrium is an independent receptivity marker in recurrent implantation failure during implantation window

Reproductive biology and endocrinology : RB&E, 2018

It is postulated that women suffered from recurrent implantation failure (RIF) have different endometrial receptivity compared to those who experienced with idiopathic recurrent miscarriage (RM). In this study, expression of common endometrial markers Leukemia inhibitor factor (LIF), mucin 1 (MUC1) and integrin β3 were studied and compared. Fourteen women with RIF, 25 with RM and 20 fertile controls were recruited for endometrial biopsy during implantation window on day LH + 7. Spatial and temporal expression of MUC1, LIF and Integrin β3 were compared using semi-quantitative immunohistochemistry. Association of MUC1, LIF and integrin β3 expression levels with demographic and clinical characteristics were determined. MUC1 expression in both luminal and glandular epithelium in women with RIF were significantly lower than that in women with RM and fertile controls. There were no differences in LIF and Integrin β3 expression in endometrial epithelium among three groups. Decreased MUC1 ...

Human Endometrial Mucin MUC1 Is Up-Regulated by Progesterone and Down-Regulated In Vitro by the Human Blastocyst1

Biology of Reproduction, 2001

Expression of MUC1 in endometrial epithelium has been suggested to create a barrier to embryo attachment that must be lifted at the time of implantation. In this study, we investigated the hormonal regulation of human endometrial MUC1 in hormone replacement therapy cycles and in the human blastocyst. We also analyzed the embryonic regulation of MUC1 in human endometrial epithelial cells (EECs) during the apposition and adhesion phases of human implantation using two different in vitro models. Our results indicate that endometrial MUC1 mRNA and immunoreactive protein increase in receptive endometrium compared to nonreceptive endometrium. Human blastocysts express MUC1, as demonstrated by reverse transcription-polymerase chain reaction and immunocytochemistry, localized at the trophectoderm. In vitro, MUC1 was present at the surface of primary cultures of human EEC, and presence of a human blastocyst (i.e., apposition phase) increases EEC MUC1 protein and mRNA compared to control EEC lacking embryos. Interestingly, when human blastocysts were allowed to attach to the EEC monolayer (i.e., adhesion phase), MUC1 was locally removed in a paracrine fashion on EEC at the implantation site. These results demonstrate a coordinated hormonal and embryonic regulation of EEC MUC1. Progesterone combined with estradiol priming induces an up-regulation of MUC1 at the receptive endometrium. During the apposition phase, presence of a human embryo increases EEC MUC1. However, at the adhesion phase, the embryo induces a paracrine cleavage of EEC MUC1 at the implantation site. These findings strongly suggest that MUC1 may act as an endometrial antiadhesive molecule that must be locally removed by the human blastocyst during the adhesion phase. implantation/early development, menstrual cycle, progesterone, uterus 1