The ZJU index is associated with the risk of obstructive sleep apnea syndrome in Chinese middle-aged and older people: a cross-sectional study

BACKGROUND

The ZJU index, a novel calculation that combines body mass index, triglycerides, fasting blood glucose and the ratio of alanine aminotransferase to aspartate aminotransferase, is a closely related measure of obesity and insulin resistance. Studies of the ZJU index in relation to obstructive sleep apnea syndrome (OSAS) have not been reported. This study assessed the correlation between the ZJU values and OSAS risk.

METHODS

A total of 2,130 participants who underwent polysomnographic monitoring were included in the study. The participants' basic information and laboratory biochemical indicators were collected, and the ZJU index was computed. The ZJU index was divided into quartiles. The correlation between the different ZJU index levels and OSAS risk was assessed using logistic regression. Drew a receiver operating characteristic (ROC) relationship curve, with prediction efficacy judged by the area under the curve (AUC), and found the optimum cut-off point for ZJU index to predict OSAS. Relative risks were presented as odds ratios (OR). The range of OR values is expressed in the form of 95% confidence intervals (95% CI).

RESULTS

The number of patients diagnosed with OSAS increased progressively with increasing ZJU index (T1: 9.4%; T2: 20.6%; T3: 28.3%; T4: 41.7%; P < 0.001). The additional confounders were adjusted by the logistic regression models, the study revealed an independent correlation between ZJU index and OSAS. (P < 0.001). The OSAS risk was notably higher at the highest ZJU index levels. (OR = 2.046 [95% CI: 1.057 to 3.964]). The ROC curve for the ZJU index showed an AUC of 0.64 (P < 0.001) for males and 0.75 (P < 0.001) for females, with a specificity of 64% and 55% and a sensitivity of 60% and 92% for males and females, respectively, with the optimum cut-off values of 36.568 and 34.722, respectively.

CONCLUSION

A high ZJU index was significantly associated with an increasing risk of OSAS. The ZJU is expected to be a meaningful index for detecting OSAS in the general population.

Association of fat-to-muscle ratio with non-alcoholic fatty liver disease: a single-centre retrospective study

OBJECTIVES

Sarcopenia is a known risk factor for non-alcoholic fatty liver disease (NAFLD). Studies evaluating the association between the fat-to-muscle ratio (FMR) and NAFLD are limited. Therefore, the aim of our study was to investigate the association between FMR and NAFLD.

DESIGN

A retrospective study was conducted on individuals who underwent health examination at Wuhan Union Hospital between January 2020 and November 2021. Clinical data were collected from electronic medical records.

SETTING

Wuhan Union Hospital, Wuhan, China.

PARTICIPANTS

1592 participants aged ≥40 years who underwent body composition analysis and liver ultrasonography were retrospectively reviewed.

OUTCOME MEASURES

Liver ultrasonography was used to assess liver steatosis, and the fibrosis-4 index was used to calculate the risk scores for liver fibrosis. The 10-year atherosclerotic cardiovascular disease (ASCVD) risk prediction model was used to calculate ASCVD risk scores.

RESULTS

The FMR was significantly higher in individuals with NAFLD than in those without NAFLD (p<0.001). The prevalence of NAFLD gradually increased from FMR tertile 1 (reference) to tertile 2 (OR=1.49, 95% CI 1.13 to 1.97) and tertile 3 (OR=2.85, 95% CI 2.08 to 3.90). In addition, patients with NAFLD in FMR tertile 3 had a significantly higher risk of liver fibrosis (OR=4.48, 95% CI 2.12 to 9.50) and ASCVD (OR=4.63, 95% CI 2.62 to 8.19) than those in FMR tertile 1 after adjustment for multiple confounders.

CONCLUSION

In this study, we found a significant association between FMR and NAFLD. A higher FMR indicates a higher risk of NAFLD in the study population and a higher risk of liver fibrosis and ASCVD in NAFLD patients.

Acupuncture and Chinese herbal medicine for menopausal mood disorder: a randomized controlled trial

OBJECTIVE

This study aimed to analyze the effectiveness of acupuncture combined with Chinese herbal medicine (CHM) on mood disorder symptoms for menopausal women.

METHODS

A total of 95 qualified Chinese participants were randomly assigned to one of three groups: 31 in the acupuncture combined with CHM group (combined group), 32 in the acupuncture combined with CHM placebo group (acupuncture group) and 32 in the CHM combined with sham acupuncture group (CHM group). The patients were treated for 8 weeks and followed up for 4 weeks. The data were collected using the Greene Climacteric Scale (GCS), self-rating depression scale (SDS), self-rating anxiety scale (SAS) and safety index.

RESULTS

The three groups each showed significant decreases in the GCS, SDS and SAS after treatment (p < 0.05). Furthermore, the effect on the GCS total score and the anxiety domain lasted until the follow-up period in the combined group (p < 0.05). Within the three groups, there was no difference in GCS and SAS between the three groups after treatment (p > 0.05). However, the combined group showed significant improvement in the SDS, compared with both the acupuncture group and the CHM group at 8 weeks and 12 weeks (p < 0.05). No obvious abnormal cases were found in any of the safety indexes.

CONCLUSIONS

The results suggest that either acupuncture, or CHM or combined therapy offer safe improvement of mood disorder symptoms for menopausal women. However, the combination therapy was associated with more stable effects in the follow-up period and a superior effect on improving depression symptoms.

A placental model of SARS-CoV-2 infection reveals ACE2-dependent susceptibility and differentiation impairment in syncytiotrophoblasts

SARS-CoV-2 infection causes COVID-19. Several clinical reports have linked COVID-19 during pregnancy to negative birth outcomes and placentitis. However, the pathophysiological mechanisms underpinning SARS-CoV-2 infection during placentation and early pregnancy are not clear. Here, to shed light on this, we used induced trophoblast stem cells to generate an in vitro early placenta infection model. We identified that syncytiotrophoblasts could be infected through angiotensin-converting enzyme 2 (ACE2). Using a co-culture model of vertical transmission, we confirmed the ability of the virus to infect syncytiotrophoblasts through a previous endometrial cell infection. We further demonstrated transcriptional changes in infected syncytiotrophoblasts that led to impairment of cellular processes, reduced secretion of HCG hormone and morphological changes vital for syncytiotrophoblast function. Furthermore, different antibody strategies and antiviral drugs restore these impairments. In summary, we have established a scalable and tractable platform to study early placental cell types and highlighted its use in studying strategies to protect the placenta.

Association of hyperuricemia combined with sarcopenia on ASCVD risk

BACKGROUND

Hyperuricemia and sarcopenia are both strongly linked to an increased risk of atherosclerotic cardiovascular disease (ASCVD), and this study was designed to look into the interactive effects of hyperuricemia on ASCVD risk.

METHODS

This study collected information from patients (N = 2647) who underwent health check-ups at the Health Care Building of Wuhan Union Hospital between January 2019 and December 2020. Skeletal muscle mass was measured using bioelectrical impedance methods. The Asian Working Group on Sarcopenia diagnostic criteria were used to classify patients with sarcopenia. ASCVD risk was calculated using the Framingham Heart Study, and ASCVD risk ≥ 20% was considered high risk ASCVD. IBM SPSS 25.0 and GraphPad prism 8.0 software were used for data analysis and graphing.

RESULTS

The prevalence of hyperuricemia and sarcopenia was 23.57% and 15.34%, respectively. The occurrence of cardiovascular risk factors such as obesity, hypertension, diabetes mellitus, chronic kidney disease, and low HDL-Cemia was significantly higher in subjects with hyperuricemia combined with sarcopenia (OR = 1.734, 3.064, 1.61, 8.77 and 1.691 respectively, p < 0.05); Hyperuricemia and high-risk ASCVD were independently associated (OR = 1.355, 95% CI = 1.000-1.838, p = 0.04). Although there was no significant association between sarcopenia and high-risk ASCVD after controlling for confounders (OR = 1.274, 95% CI = 0.828-1.959, p = 0.271), sarcopenia combined with hyperuricemia significantly increased high-risk ASCVD (OR = 3.229, 95% CI 1.544-6.751, p = 0.002).

CONCLUSION

Hyperuricemia is independently associated with high-risk ASCVD; Sarcopenia and high-risk ASCVD did not show an independent relationship, but there was a synergistic effect of the two on ASCVD risk, which may imply that managing both hyperuricemia and sarcopenia may have a greater cardiovascular benefit.

Combining Fat-to-Muscle Ratio and Alanine Aminotransferase/Aspartate Aminotransferase Ratio in the Prediction of Cardiometabolic Risk: A Cross-Sectional Study

PURPOSE

Altered body composition and liver enzymes are known to be related to cardiometabolic risk. Our study aimed to evaluate the association between fat-to-muscle ratio (FMR), alanine aminotransferase/aspartate aminotransferase (ALT/AST) ratio and cardiometabolic risk.

METHODS

In total, 1557 participants aged ≥40 years were included. A bioelectrical impedance analyzer (BIA) was used to measure fat mass and muscle mass. We created a cardiometabolic risk score with one point for each cardiometabolic risk factor, including elevated triglycerides (TGs), decreased high-density lipoprotein cholesterol (HDL-C), elevated blood pressure (BP), and abnormal blood glucose, yielding a score of 0-4 for each participant (≥2 for high-risk and <2 for low-risk). Logistic regression analyses were used to analyze the relationship between FMR, ALT/AST ratio and cardiometabolic risk.

RESULTS

FMR and ALT/AST ratio were significantly higher in the high-risk group than in the low-risk group (P<0.001). FMR and ALT/AST ratio were both positively correlated with a higher cardiometabolic risk score and the presence of each cardiometabolic risk factor. In subgroup analyses categorized according to FMR and ALT/AST ratio cutoffs, the high-FMR/high-ALT/AST group had the highest cardiometabolic risk (OR=8.51; 95% CI 4.46-16.25 in women and OR=5.09; 95% CI 3.39-7.65 in men) after adjusting for confounders.

CONCLUSION

FMR and ALT/AST ratio were positively associated with cardiometabolic risk. Combining these two indicators improved the prediction of cardiometabolic risk.

Correlation Analysis between Uric Acid and Metabolic Syndrome in the Chinese Elderly Population: A Cross-Sectional Study

BACKGROUND

Currently, both metabolic syndrome and hyperuricaemia have attracted extensive attention in public health. The correlation between uric acid and metabolic syndrome is controversial. Research on the relationship between uric acid and metabolic syndrome in community-dwelling elderly people is relatively lacking. The purpose of this study is to explore the relationship between uric acid and metabolic syndrome in the community-dwelling elderly people.

DESIGN

Cross-sectional study.

METHODS

We collected the physical examination data of 1,267 elderly people in Gutian community in Wuhan and used SPSS IBM 25.0 for data analysis. Correlation and logistic regression analyses were performed, and ROC curves were drawn.

RESULTS

The uric acid level of the nonmetabolic syndrome group was lower than that of the metabolic syndrome group (337.31 vs. 381.91 µmol/L; P < 0.05). Uric acid was positively correlated with systolic blood pressure (r = 0.177, P < 0.001), diastolic blood pressure (r = 0.135, P < 0.001), body mass index (r = 0.234, P < 0.001), waist circumference (r = 0.283, P < 0.001), and triglycerides (r = 0.217, P < 0.05). High-density lipoprotein cholesterol (r = -0.268, P < 0.001) showed the opposite trend. Logistic regression analysis results suggested that uric acid is a risk factor for metabolic syndrome. The result is described as exp (B) and 95% CI (1.003 [1.001, 1.005]). Based on the receiver operating characteristic curve, we found that the area under the curve of uric acid to diagnose metabolic syndrome was 0.64 (sensitivity: 79.3%, specificity: 45.1%).

CONCLUSION

We observed an association between uric acid levels and metabolic syndrome in the elderly Chinese population. The best threshold value for uric acid in predicting metabolic syndrome diagnosis was 314.5 μmol/l.

High TG/HDL ratio suggests a higher risk of metabolic syndrome among an elderly Chinese population: a cross-sectional study

OBJECTIVES

To investigate the relationship between triglyceride/high-density lipoprotein cholesterol (TG/HDL-C) ratio and metabolic syndrome in the elderly population of China, and to determine the best critical value of TG/HDL-C in higher risk of metabolic syndrome in this population.

DESIGN

Cross-sectional study.

SETTING

Our study was conducted in a community physical examination centre in Wuhan, China between 1 January 2016 and 31 December 2016.

PARTICIPANTS

The physical examination data from 1267 elderly people (aged over 65 years) in the community were analysed in this study. The average age of the study participants was 71.64±5.605 years.

PRIMARY OUTCOME MEASURES

Correlation between the TG/HDL-C ratio and metabolic syndrome; the optimum cut-off of the TG/HDL-C ratio for the prediction of metabolic syndrome.

RESULTS

The TG/HDL-C ratio showed a significant positive correlation with metabolic syndrome (r=0.420, p<0.001) in the elderly Chinese population. Binary logistic regression analysis showed that the TG/HDL-C ratio was an independent risk factor for metabolic syndrome (OR=3.07 (95% CI: 2.402 to 3.924), p<0.001) after adjusting for blood pressure, blood glucose, age, sex and body mass index. The receiver operating characteristic curves of TG/HDL-C ratio and metabolic syndrome showed that in the elderly population, a TG/HDL-C ratio of 1.49 can be used as the critical value for a higher risk of metabolic syndrome. At this value, the specificity and sensitivity of the measure were optimal (80.8% and 72.4%, respectively).

CONCLUSION

In this study, we found a significant correlation between TG/HDL-C ratio and metabolic syndrome. And high TG/HDL ratio suggests a higher risk of metabolic syndrome among an elderly Chinese population.

Second- and third-trimester serum levels of growth-differentiation factor-15 in prediction of pre-eclampsia

OBJECTIVE

Pre-eclampsia (PE) is a significant contributor to adverse maternal and perinatal outcome; however, accurate prediction and early diagnosis of this condition remain a challenge. The aim of this study was to compare serum levels of growth-differentiation factor-15 (GDF-15) at three different gestational ages between asymptomatic women who subsequently developed preterm or term PE and healthy controls.

METHODS

This was a case-control study drawn from a prospective observational study on adverse pregnancy outcomes in women attending for their routine second- and third-trimester hospital visits. Serum GDF-15 was determined in 300 samples using a commercial GDF-15 enzyme-linked immunosorbent assay: 120 samples at 19-24 weeks of gestation, 120 samples at 30-34 weeks and 60 samples at 35-37 weeks. Multiple linear regression was applied to logarithmically transformed GDF-15 control values to evaluate the influence of gestational age at blood sampling and maternal characteristics on GDF-15 results. GDF-15 multiples of the normal median (MoM) values, adjusted for gestational age and maternal characteristics, were compared between pregnancies that subsequently developed preterm or term PE and healthy controls.

RESULTS

Values of GDF-15 increased with gestational age. There were no significant differences in GDF-15 MoM values between cases of preterm or term PE and normotensive pregnancies at 19-24 or 35-37 weeks of gestation. At 30-34 weeks, GDF-15 MoM values were significantly increased in cases of preterm PE, but not in those who later developed term PE. Elevated GDF-15 MoM values were associated significantly with a shorter interval between sampling at 30-34 weeks and delivery with PE (P = 0.005).

CONCLUSION

Serum GDF-15 levels at 19-24 or 35-37 weeks of gestation are not predictive of preterm or term PE. At 30-34 weeks, GDF-15 levels are higher in women who subsequently develop preterm PE; however, this difference is small and GDF-15 is unlikely to be useful in clinical practice when used in isolation. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Metabolic regulation of polyamines and γ-aminobutyric acid in relation to spermidine-induced heat tolerance in white clover

Heat stress decreases crop growth and yield worldwide. Spermidine (Spd) is a small aliphatic amine and acts as a ubiquitous regulator for plant growth, development and stress tolerance. Objectives of this study were to determine effects of exogenous Spd on changes in endogenous polyamine (PA) and γ-aminobutyric acid (GABA) metabolism, oxidative damage, senescence and heat shock protein (HSP) expression in white clover subjected to heat stress. Physiological and molecular methods, including colorimetric assay, high performance liquid chromatography and qRT-PCR, were applied. Results showed that exogenous Spd significantly alleviated heat-induced stress damage. Application of Spd not only increased endogenous putrescine, Spd, spermine and total PA accumulation, but also accelerated PA oxidation and improved glutamic acid decarboxylase activity, leading to GABA accumulation in leaves under heat stress. The Spd-pretreated white clover maintained a significantly higher chlorophyll (Chl) content than untreated plants under heat stress, which could be related to the roles of Spd in up-regulating genes encoding Chl synthesis (PBGD and Mg-CHT) and maintaining reduced Chl degradation (PaO and CHLASE) during heat stress. In addition, Spd up-regulated HSP70, HSP70B and HSP70-5 expression, which might function in stabilizing denatured proteins and helping proteins to folding correctly in white clover under high temperature stress. In summary, exogenous Spd treatment improves the heat tolerance of white clover by altering endogenous PA and GABA content and metabolism, enhancing the antioxidant system and HSP expression and slowing leaf senescence related to an increase in Chl biosynthesis and a decrease in Chl degradation during heat stress.

[Effects of Prrx2 gene silencing on the proliferation of breast cancer and its molecular mechanisms]

Objective: The aim of this study was to investigate the effects of silencing Paired related homoeobox 2 (Prrx2) expression on the proliferation of breast cancer and its molecular mechanisms. Methods: Short hairpin RNA knockdown of Prrx2 was used to examine cellular effects of Prrx2. The level of Prrx2 was verified by Western blot. MTT assay was used to analyze the proliferation of breast cancer cells in vitro. To investigate the effect of Prrx2 depletion on tumor growth in vivo, a nude mouse xenograft model was performed. Results: The expression of Prrx2 decreased 91.2% in MDA-MB-231 cells and 88.7% in MCF-7 cells after transfection with interfering vectors (P<0.05). MTT assay showed that the proliferation of cells in silenced Prrx2 expression group was significantly inhibited compared with the control group (P<0.05). Nude mice transplanted tumors showed that the growth of transplanted tumors was slow after silencing Prrx2 expression, and the weight of the tumors of silenced Prrx2 expression group were smaller than those of the control group ((160.2±26.3)mg vs (365.4±19.7)mg, P<0.05). Western blot showed that silencing Prrx2 expression inhibited the expression of β-catenin in breast cancer cell nucleus and down-regulated the activity of Wnt/β-catenin signaling pathway. Conclusions: Silencing Prrx2 expression can effectively inhibit the proliferation and growth of breast cancer, suggesting that Prrx2 may become a new target for the treatment of breast cancer.

MiRNA-106a promotes breast cancer progression by regulating DAX-1

OBJECTIVE

The aim of this study was to explore the expression of microRNA-106a in breast cancer (BC) and to further investigate its role in BC development and the potential regulatory mechanism.

PATIENTS AND METHODS

72 pairs of BC tissues and para-cancerous tissues were collected, and microRNA-106a expression was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The relationship between microRNA-106a expression and BC pathological parameters was analyzed. Meanwhile, the expression of microRNA-106a in BC cells was verified by qRT-PCR as well. In addition, microRNA-106a knockdown model was constructed by transfecting small interfering RNA in BC cell lines including MCF-7 and SKBR3. Subsequently, the effects of microRNA-106a on biological functions of BC cells were analyzed by cell counting kit-8 (CCK-8), 5-ethynyl-2'-deoxyuridine (EDU), and transwell invasion and migration assays, respectively. Finally, the underlying mechanism was explored by cellular rescue experiment.

RESULTS

QRT-PCR results illustrated that microRNA-106a expression in BC tissues was markedly higher than that of normal tissues. Patients with high expression of microRNA-106a exhibited significantly higher tumor stage as well as higher incidence of lymph node metastasis and distant metastasis when compared with those with low expression. Cell proliferation, invasion, and migration abilities in microRNA-106a inhibitor group were markedly decreased when compared with control group. Subsequent experiments demonstrated that DAX-1 expression was reduced in BC cell lines and tissues. Moreover, DAX-1 expression was negatively correlated with microRNA-106a expression. In addition, a recovery experiment found that microRNA-106a and DAX-1 had mutual regulation, which could affect the malignant progression of BC.

CONCLUSIONS

We found that the expression of microRNA-106a was significantly increased in BC. Meanwhile, microRNA-106a expression was closely related to BC stage, distant metastasis, lymph node metastasis, and poor prognosis. Therefore, microRNA-106a promoted the invasion, migration, and proliferation of BC by targeting DAX-1.

MicroRNA-509-5p functions as an anti-oncogene in breast cancer via targeting SOD2

OBJECTIVE

Breast cancer is one of the most common malignant tumors in women worldwide. Considering the poor therapeutic effect of breast cancer, we are supposed to dissect the functioning mode of miR-509-5p on breast cancer cell growth and metastasis, providing therapeutic targets for breast cancer.

PATIENTS AND METHODS

Quantitative Real-time PCR (qRT-PCR) assay was employed to detect miR-509-5p expression level. CCK8 assay and colony formation assay were incorporated to assess cell viability and proliferation capacities. Cell migration and invasion assay were performed to investigate metastasis capacity of breast cancer cells. Flow cytometry was used to identify cell apoptosis and cell cycle distribution. Protein levels were assessed by Western blotting assay. The target gene was predicted and verified by bioinformatics analysis and luciferase assay.

RESULTS

MiR-509-5p was obviously downregulated in breast cancer tissues when compared with pericarcinomatous tissues (n=76). Overexpressed miR-509-5p could attenuate breast cancer cell viability, proliferation, migration and invasion capacities, as well as promote cell apoptosis and induce cell cycle arrest at G0/G1 phase. Superoxide dismutase 2 (SOD2) was chosen as the target gene of miR-509-5p by bioinformatic analysis and Luciferase reporter assay. Moreover, restoration of SOD2 could rescue tumor suppression role of miR-509-5p on breast cancer tumorigenesis.

CONCLUSIONS

MiR-509-5p exerted tumor-suppressive effects on breast cancer progression and metastasis via targeting SOD2 in vitro, which provided an innovative and candidate target for diagnose and treatment of breast cancer.

Meta-analysis of IL-6 -174G/C polymorphism and psoriasis risk

Previous studies examining the association between interleukin-6 (IL-6) -174G/C polymorphism and psoriasis risk have produced inconsistent results. The aim of this study was to offer a comprehensive review of the association between IL-6 -174G/C polymorphism and psoriasis risk through a meta-analysis. Literature search of PubMed and Embase databases was conducted to identify all eligible studies published before October 29, 2015. Four case-control studies involving 651 psoriasis cases and 552 controls were included in this meta-analysis. Data were extracted, and pooled odds ratios (ORs) with 95% confidence intervals (CIs) were calculated to assess the associations. Combined analysis revealed a significant association between this polymorphism and psoriasis risk under the recessive model (OR = 1.69, 95%CI = 1.12-2.55, P = 0.013 for GG vs GC + CC), and the heterozygous comparison model (OR = 1.70, 95%CI = 1.29-2.23, P < 0.001 for GG vs GC). However, no significant association was observed under the allelic model (OR = 1.37, 95%CI = 0.99-1.89, P = 0.060 for G vs C), the dominant model (OR = 1.25, 95%CI = 0.92-1.71, P = 0.152 for GG + GC vs CC), and the homozygote comparison model (OR = 1.62, 95%CI = 0.79-3.32, P = 0.186 for GG vs CC). We conclude that the IL-6 -174G/C polymorphism contributes to psoriasis risk. However, further studies should be performed to validate our results.

Risk factors of node metastasis in cervical carcinoma

Purpose ofinvestigation: To investigate the metastatic risk factors of pelvic lymph nodes in patients with cervical carcinoma in Stage Ia2 and IIa2.

MATERIALS AND METHODS

The clinic pathologic parameters in 337 patients with Stage Ia2-IIa2 cervical carcinoma were retrospectively analyzed. The risk factors for pelvic lymph node metastasis were evaluated by the way of univariate X2 statistic analysis and binary logistic regression analysis.

RESULTS

The lymph nodes metastasis rate was 11.87% (40/337). Single variable analysis showed that age, clinical stage, the size of tumor ≥ four cm, depth of stromal invasion 2/3, lymph-vascular space involvement (LVSI), and parametrial extension were related to the metastasis of lymph nodes. Multivariate analysis showed that the size of tumor, depth of stromal invasion, LVSI, and parametrial extension were independent risk factors.

CONCLUSION

Patients with tumor size ≥ four cm, stromal invasion ≥ 2/3, LVSI, and parametrial extension were at high risk of lymph node metastasis.

Association between IL-21 polymorphism and systemic lupus erythematosus: a meta-analysis

Several case-control studies have been conducted to investigate the association between Interleukin-21 (IL-21) polymorphisms and systemic lupus erythematosus (SLE) susceptibility, and most of the studies focused on IL-21 rs907715 and rs2221903 polymorphisms. Given the inconsistent results from these studies, the present meta-analysis aimed to obtain a more precise estimate of the association between IL-21 rs907715 and rs2221903 polymorphisms and SLE. Studies regarding these specific polymorphisms and SLE were retrieved from PubMed, Embase, Web of Science, CNKI, and CBM. Data were extracted and meta-analysis was performed using the STATA 12.0 software. For the IL-21 rs907715 polymorphism, seven sets of comparisons involving 7977 SLE cases and 8097 healthy controls were considered. Results showed that there were significant differences in the IL-21 rs907715 genotype distribution between SLE patients and healthy controls in the comparisons of all genetic models. Upon stratified analysis by ethnicity, a similar result was found in the Caucasian and African-American population. For the IL-21 rs2221903 polymorphism, seven sets of comparisons involving 7990 SLE cases and 8098 healthy controls were considered. Results showed that there were significant differences in the IL-21 rs2221903 genotype distribution between SLE patients and healthy controls in the comparisons of GG versus AA and GG versus GA+AA. Upon stratified analysis by ethnicity, a similar result was found in the Caucasian population. This meta-analysis suggests that the both IL-21 rs907715 and rs2221903 polymorphisms may be associated with SLE susceptibility. As current evidence remains limited, further studies are needed to warrant the association between IL-21 rs907715 and rs2221903 polymorphisms and SLE susceptibility.

Role of hydroxyethyl starch in ischemia-reperfusion injury in rat intestinal transplantation

OBJECTIVE

This study was designed to evaluate the role of 0%, 3%, 6% hydroxyethyl starch (HES) and University of Wisconsin (UW) perfusion and preservation solutions on ischemia-reperfusion injury (IRI) of rat intestinal transplantations, solutions, respectively.

MATERIALS AND METHODS

Rats underwent orthotopic intestinal transplantation (Lewis to Lewis) after using perfusion and preservation saline (group l), 3% HES (group 2), 6% HES (group 3), or UW (group 4) solutions. The change in weight was recorded from preoperative to postoperative day (POD) 30. At 30 minutes after reperfusion, we harvested intestinal juice preoperatively as well as at 30 minutes after reperfusion and on POD 1 and 3 when recipients underwent open surgery for maltose absorption tests and sampling. The Park' scores of IRI were evaluated by light microscopy after hematoxylin and eosin (H&E) staining.

RESULTS

An increased weight was more evident in group 2 than the other groups, particularly the on POD 1 and POD 3 (P < .05). It was significantly greater than groups 1 and 3 on POD 7 (P < .05). Compared with the other groups, the 30-minute post-reperfusion. Park score and intestinal juice content in group 2 was decreased significantly (P < .01), while in group 3 the Park score was increased, and the maltose absorption level decreased significantly (P < .05).

CONCLUSION

Three percent HES solution attenuated IRI in rat intestinal transplantation. High-concentration HES solutions were unfit for intestinal preservation. Thus the adverse effects of UW solution may be attribute at least in part to its high HES, concentration.

Uterine lavage or aspirate: which view of the intrauterine environment?

Fluid within the uterine cavity provides the microenvironment for preimplantation blastocyst development and early implantation. Analysis of uterine fluid sampled by aspiration or lavage provides a view of this microenvironment but the similarity or otherwise of the sample components is not known. This study compared proteins in aspirates versus lavage samples taken sequentially from the same women, using surface-enhanced laser desorption/ionization-time of flight-mass spectrometry (SELDI-TOF-MS), multiplex cytokine assays, and an activity assay for proprotein convertase 6. Both lavage and aspiration enabled analysis of uterine fluid components, but they provided substantially different protein profiles. Although there were many similarities in overall protein profiles and most specific proteins examined were detected in both fluids, these were neither qualitatively nor quantitatively comparable within each participant. A likely explanation is that lavage samples the entire uterine cavity including washing the endometrial surface (glycocalyx), whereas aspiration sampling is very local.

Abstract P3-12-08: Molecular Breast Cancer Subtypes in Women from Northeast China: Eight-Year Retrospective Study about Clinicopathologic Features and Survival

Background and objectives: Analysis of gene expression has identified various molecular subtypes. These molecular subtypes defined by immunohistochemistry expression of estrogen receptor (ER) or progesterone receptor (PR) and human epidermal growth factor receptor 2 (Her2) : luminal A, luminal B, basal cell-like and HER2-expresing. This study evaluates clinical and pathologic features and survival of the four molecular subtypes in premenopausal and postmenopausal women from northeast China.

Methods: A retrospective analysis of 1214 women diagnosed with breast cancer from 2000 to 2007 in Breast Surgery Department, First Hospital of Jilin University. Four molecular breast cancer subtypes defined as: luminal A (ER+ and/or PR+, HER2-), luminal B (ER+ and/or PR+, HER2+), basal-like (ER-, PR-, HER2-), and HER2-expresing, (ER-, PR-, and HER2+). We examined the prevalence of breast cancer subtypes and analyzed the associations with patient clinicopathologic features: age, menopausal status, tumor size, lymph node status, stage of cancer at diagnosis, histological characteristics, and breast cancer-specific survival.

Results: Among the all cases, the luminal A subtype was the most prevalent in our study sample (56.0%) compared with basal -like (18.5%), luminal B (13.7%), and HER2-expresing subtypes (11.8%). The four molecular subtypes differed significantly by menopausal status (P=0.011), age (P&lt;0.001) and lymph node status (P&lt;0.001). Luminal A subtype was more likely to with Stage II breast cancer (P&lt;0.001) and most present with size of 2.1-5 cm (P&lt;0.001). The luminal B and the HER2-expresing subtypes presented an increased association with more aggressive clinical course when compared with others subtypes. The estimated median follow-up period for all subjects was 54 months (range, 1 month to 120 months). The 8-year overall survival for all patients was 81.3% (95%CI, 79.4-83.7) and disease-free survival was 77.8% (95% CI, 75.4-79.9). The Kaplan-Meier curve showed breast cancer-specific survival differed significantly among the molecular subtypes (P &lt; 0.03), with the luminal B and HER2-expresing subtypes having the poorest outcome.

Conclusion: Luminal A breast tumor appeared the better outcome than the others three subtypes and the shortest survival was HER2-expresing subtype. The poor clinical outcomes of luminal B subtype with women from northeast China were different from those of Western women could contribute to the poor prognosis of breast cancer observed in this cohort of patients and some of them couldn't accept molecular targeted therapy with trastuzumab by poor economic situations.

Figure available in online version.

164. INTEGRIN CLEAVAGE IS MEDIATED BY PROPROTEIN CONVERTASE 6 IN HUMAN ENDOMETRIAL EPITHELIAL CELLS FOR ENDOMETRIAL RECEPTIVITY AND IMPLANTATION

Integrins are transmembrane glycoproteins composed of non-covalently associated α and β chains. Integrins participates in cell–cell interaction and binding to components of the extracellular matrix. Integrin expression changes during the establishment of receptivity for implantation. Integrins α1β1, α4β1 and αvβ3 are expressed in the endometrium during the window of implantation [1, 2] and deficiency in integrin αvβ3 is associated with idiopathic infertility and delayed endometrial maturation [1, 3, 4]. Proprotein convertases (PCs) cleave proproteins at the basic amino acids consensus motif (K/R)-(X)n-(K/R)↓ (where n = 0, 2, 4 or 6 and X is any aa) for activation. Integrins require post-translational cleavage for activation and are known to be cleaved by PCs. PC6 plays a critical role in the establishment of endometrial receptivity. We hypothesized that PC6 cleaves integrins for its activation in the endometrial epithelium for implantation. The aim of this study was to investigate the functional importance of PC6 in integrin cleavage, using a stable PC6-knockdown in HEC1A cells (HEC1A-HP) by siRNA technology.Cells transfected with a scrambled siRNA sequence (HEC1A-control) were used as the control. To determine the amount of functional integrins on the cell surface, HEC1A-PC6 and HEC1A-control were subjected to an integrin monoclonal antibody array. The amount of functional integrins α1, α3, α5, αv, αvβ3, β1, β3, β4 and α5β1 on the cell surfacewas much less in HEC1A-HP than HEC1A-control cells. Western blot analysis confirmed that cleavage of pro-integrin α5 into disulfide-linked heavy chain (110kDa) and light chain (35kDa) was greater in HEC1A-control compared to HEC1A-HP cells, suggesting that knockdown of PC6 affects integrin cleavage. Our studies imply that integrin cleavage is mediated by PC6 in endometrial epithelial cells for the establishment of receptivity for embryo implantation. (1) Lessey BA, et al., Integrin adhesion molecules in the human endometrium. Correlation with the normal and abnormal menstrual cycle. J Clin Invest, 1992. 90(1): 188–95.(2) Tabibzadeh S, Patterns of expression of integrin molecules in human endometrium throughout the menstrual cycle. Hum Reprod, 1992. 7(6): 876–82.(3) Lessey BA, et al., Further characterization of endometrial integrins during the menstrual cycle and in pregnancy. Fertil Steril, 1994. 62(3): 497–506.(4) Lessey BA, et al., Aberrant integrin expression in the endometrium of women with endometriosis. J Clin Endocrinol Metab, 1994. 79(2): 643–9.

304. DECIDUAL HtrA3 NEGATIVELY REGULATES TROPHOBLAST INVASION

Controlled trophoblast invasion cell into the maternal decidua (interstitial invasion) is important for placental development. Abnormalities in the invasion process may lead to pregnancy complications. Decidua secrets many factors to control trophoblast invasion. Serine protease HtrA3 is highly expressed in the decidual cells in the late secretory phase of the menstrual cycle and throughout pregnancy. It is highly expressed in first trimester in most trophoblast cell types, but not in the invading interstitial trophoblast. HtrA3 and its family members are down-regulated in a number of cancers and are proposed as tumor suppressors. We hypothesized that HtrA3 is an inhibitor of trophoblast invasion. The current study aimed to investigate whether HtrA3 secreted by decidual cells regulates trophoblast invasion. Human endometrial stromal cells (HESC) were decidualised with estradial, medroxyprogesterone acetate and cyclic AMP. Real-time RT-PCR, western blotting and immunocytochemistry demonstrated that decidualisation increased HtrA3 mRNA and protein expression. HtrA3 was also detected by western blotting in the conditioned media (CM) of decidualised HESC (96h), confirming its secretory nature. For functional studies, wild type and protease inactive mutant HtrA3 were produced using wheat germ cell-free technology. The mutant has negligible protease activity and significantly inhibited the wild type protease activity, supporting its dominant-negative inhibition and utility as a specific inhibitor of the wild type protein. CM of decidualised HESC suppressed invasion of trophoblast HTR-8 cells, whereas inhibition of HtrA3 in the decidual HESC CM by exogeneous addition of HtrA3 mutant increased trophoblast HTR-8 cell invasion. These results strongly support our hypothesis that decidual HtrA3 negatively regulates trophobalst invasion.

115. DEVELOPMENT OF POTENT AND STABLE PC6 INHIBITORS TO BLOCK EMBRYO IMPLANTATION FOR FEMALE CONTRACEPTION AND PREVENTION OF HIV

Proprotein convertase (PC) 6, a member of the PC family that activate precursor proteins into their active forms, is a critical endometrial factor for embryo implantation. Blocking PC6 production in mice inhibits decidualisation (a critical process of implantation) and inhibits implantation. PCs including PC6 also play a critical role in HIV infection through cleaving HIV envelope precursor protein gp160 into functional gp120 and gp41. PC inhibitors are demonstrated to inhibit HIV transmission via blocking gp160 cleavage. We hypothesised that PC6 is a potential target for the development of female contraception that could also provide protection from HIV infection. One key requirement to prove this concept in an animal model is a potent PC6 inhibitor that is stable in serum. Polyarginine peptide (polyR) is published to be a potent PC6 inhibitor that also inhibits HIV. We have confirmed that polyR inhibits PC6 in vivo and completely blocks decidualisation of human endometrial stromal cells in culture. However, polyR has short serum half-life. The aim of this current study was to generate polyR derivatives that are potent PC6 inhibitors, with increased serum stability. We modified polyR by either PEGylation with different sized PEG (polyethylene glycol) or cyclization, and tested their potency, stability and utility in vivo. Modifications at both terminals of polyR dramatically reduced its PC6 inhibitory potency. PEGylation at the C-terminal, regardless of the PEG size, had no effect. In silico docking experiments showed that N-terminal PEGylation or cyclization affected the binding of polyR to the PC6 active site, but not C-terminal PEGylation. One of the polyR derivatives, C-30kDa-PEG polyR was confirmed to be as potent as the parental peptide but much more stable in serum. Studies are currently in place to inhibit embryo implantation in mice using C-30kDa-PEG polyR and to determine its ability to inhibit HIV.

156. IDENTIFICATION OF SCAFFOLDING PROTEINS AS PC6 SUBSTRATES IN THE HUMAN ENDOMETRIAL EPITHELIAL CELLS FOR EMBRYO IMPLANTATION

Successful embryo implantation is an important step in establishing pregnancy, which requires a healthy embryo and a receptive endometrium. Establishment of endometrial receptivity involves morphological and physiological changes initially in the endometrial epithelium, however the underlying molecular mechanisms are not fully understood. We have previously demonstrated that proprotein convertase 5/6 (PC6), a member of the proprotein convertase (PC) family, is up-regulated in the endometrium specifically at implantation in association with epithelial differentiation in the human and monkey. PCs convert a range of precursor proteins of important functions into their bioactive forms, they are thus regarded as critical ‘master switch’ molecules. The aim of this study was to identify target proteins of PC6 in the endometrial epithelial cells important for implantation. We used a HEC1A cell line in which PC6 was stably knocked down by siRNA approach (HEC1A-PC6). HEC1A cells that were similarly transfected with a scrambled siRNA sequence (HEC1A-control) were used as the control. Previous study confirmed that HEC1A-PC6 cells had much reduced capacity to adhere to blastocyst. A proteomic comparison between HEC1A-PC6 treated with or without human recombinant PC6 identified ezrin as a potential PC6 substrate. Ezrin is a cytoplasmic protein which is known to bind to ezrin-radixin-moesin-binding phosphoprotein 50 (EBP50) thereby translocating to the plasma membrane.This complex has been associated with cytoskeletal re-organisation and changes in cell polarity. Co-immunoprecipitation of ezrin and EBP50 showed that knockdown of PC6 allowed the binding of ezrin to the C-terminus of EBP50 in HEC1A-PC6, whereas PC6 cleavage of EBP50 in HEC1A-control prevented the binding. This was also confirmed by immunofluorescence showing that ezrin and EBP50 were co-localized to the plasma membrane in HEC1A-PC6. This study thus identified that PC6 regulates scaffolding proteins such as EBP50 and ezrin in the endometrium for embryo implantation.

309. DEVELOPMENT AND VALIDATION OF AN ELISA FOR HIGH TEMPERATURE REQUIREMENT FACTOR A3 (HtrA3): EARLY DETECTION OF PREECLAMPSIA

Preeclampsia (PE) is a multisystemic condition in pregnant women that can be life threatening for both mother and baby. PE is a hypertensive disorder that develops concurrently with proteinuria after 20 weeks of gestation. Abnormal placental development during early pregnancy precedes the onset of PE later in gestation. Early diagnosis of PE is essential to reduce PE-related mortality and morbidity. To date there is no clinically useful biochemical diagnostic method that can detect PE during early pregnancy. Our laboratory discovered and cloned the serine protease HtrA3 and has shown that HtrA3 protein levels are intimately involved in placentation (1). Persistently high serum levels of HtrA3 are detected at the end of the first trimester in pregnant women who subsequently develop PE, suggesting that monitoring HtrA3 in maternal blood during early pregnancy may identify women at risk for PE. To develop monoclonal antibodies specific for HtrA3; and to develop an enzyme-linked immunosorbent assay (ELISA) to detect HtrA3 in human sera. Monoclonal antibodies were generated against full length human HtrA3 and small HtrA3 peptides and tested on recombinant HtrA3, human sera and first trimester decidual and villous tissues using western blot, immunoprecipitation and Amplified luminescent proximity homogeneous assay (Alpha)LISA technology. Three antibody pairs were identified that detected either short and/or long isoforms of HtrA3 in sera and placental tissues. Recombinant HtrA3 was detected by AlphaLISA and higher levels of HtrA3 were detected in serum of PE women compared to gestation-matched controls in preliminary testing. These antibody pairs can now be used for the development of specific and high throughput assays. The AlphaLISA will then be used to validate that abnormal serum HtrA3 levels during early pregnancy can predict preeclampsia. (1) Nie et al, (2006) Biol Reprod 74, 366–374.

151. PLACENTAL HtrA3 IS REGULATED BY OXYGEN TENSION AND SERUM LEVELS ARE ALTERED DURING EARLY PREGNANCY IN WOMEN DESTINED TO DEVELOP PREECLAMPSIA

The pathogenic origin of preeclampsia is defective placental development (placentation) and function. Preeclampsia is not diagnosed until later in pregnancy and reliable early detection is highly desirable. HtrA3 is a recently cloned gene with high expression during placentation in the mouse, rhesus monkey and human. In human 1st trimester placenta, HtrA3 is highly expressed in maternal decidual cells and in certain trophoblast cell types. Placental HtrA3 is secreted into the maternal circulation and clearly detectable in serum of pregnant women in the 1st trimester. The present study examined placental production and serum profile of HtrA3 across gestation in women, the potential molecular mechanisms regulating HtrA3 production, and association between maternal HtrA3 serum levels and preeclampsia. Immunohistochemistry determined HtrA3 expression pattern and cellular localization in 1st, 2nd and 3rd trimester placenta. Maternal serum HtrA3 levels were analysed by Western blotting. Regulation of placental HtrA3 production and secretion by oxygen tension was investigated in 1st trimester placental explants and trophoblast cells. Placental HtrA3 protein was maximally produced in the 1st trimester, then dramatically down-regulated, especially in the syncytiotrophoblast. HtrA3 was secreted into the maternal circulation with a serum profile reflecting placental production. Oxygen tension regulated HtrA3; low oxygen enhanced, while transition from low-to-high oxygen decreased, HtrA3 protein production in syncytiotrophoblast. Maternal serum HtrA3 levels at ~13-14 weeks of gestation were significantly higher in women who subsequently developed preeclampsia. It appeared that HtrA3 down-regulation was delayed in preeclamptic pregnancies. In conclusion, HtrA3 protein production is closely associated with oxygen tension in the placenta. The decline in HtrA3 at the end of 1st trimester may reflect the placental low-to-high oxygen switch. Abnormally high levels of serum HtrA3 at the end of 1st trimester is associated with preeclampsia.

166. EMBRYO IMPLANTATION IS ASSOCIATED WITH SPECIFIC EXPRESSION OF PROPROTEIN CONVERTASE 6 IN THE RABBIT UTERUS

Proprotein convertase 5/6 (PC6) is a member of the proprotein convertase family that endoproteolytically cleave latent precursor proteins into their biologically active state. We have previously demonstrated that endometrial PC6 is critical for embryo implantation in mice and primates, including human. PC6 regulates the endometrial physiology specifically at implantation in association with epithelial differentiation during the establishment of endometrial receptivity (in human and monkey) and stromal cell decidualization (in the mouse, human and monkey). PC6 was further confirmed to be a unique PC member that is tightly regulated in the endometrium in relation to implantation. Our further studies (unpublished) suggest that PC6 regulates adhesion molecules in the endometrial epithelium for implantation in women. It is known that between the mouse and human, the endometrial stroma-mediated responses are similar whereas the epithelial cells behave differently. Because PC6 regulates primarily the stromal component (decidualization) in the mouse, in vivo mouse models are critical to investigate the roles of PC6 in decidualization. To address the function of PC6 in endometrial epithelium, non-mouse models relevant to human implantation are required. The rabbit is regarded as an excellent model to study the molecular events of embryo adhesion and attachment. The current study aimed to determine the expression pattern and localisation of PC6 in the rabbit uterus during early pregnancy. Quantitative RT-PCR analysis showed that PC6 mRNA expression was dynamically up-regulated in the rabbit uterus immediately prior to implantation. Western blotting and immunohistochemical analyses demonstrated that PC6 protein was predominantly localised to the basal glands throughout pregnancy, and up-regulated specifically in the epithelium at the embryo attachment site. These findings suggest that PC6 may play an essential role in rabbit implantation, and that the rabbit is a useful animal model to investigate the function of PC6 during embryo attachment.

171. IDENTIFICATION OF DECIDUALISATION-INDUCED PROTEIN CHANGES IN HUMAN ENDOMETRIAL STROMAL CELLS BY PROTEOMICS

Decidualisation of human endometrial stromal cells (HESC) is pivotal for successful implantation and can be induced by cAMP analogues such as 8-bromo-cyclic adenosine monophosphate (8-Br-cAMP) and ligands to enhance cellular cAMP levels. The resulting decidualisation HESC is recognised by morphological changes and cellular products such as prolactin or insulin-like growth factors. The regulation of proteins during decidualisation HESC has yet to be clearly identified. The aim of this study was to identify proteins that are altered during decidualisation. HESC were isolated and decidualised with 500μM of 8-Br-cAMP for 72 hours. Decidualisation success was determined by prolactin assay. 2D differential in-gel electrophoresis (DIGE) was used to examine differentially expressed proteins between control and 8-Br-cAMP treated HESC. The proteins of interest were validated by Western blot and/or immunohistochemistry. A total of 88 differentially expressed proteins were identified by matrix assisted laser desorption/ionisation (MALDI) and/or liquid chromatography mass spectrometry (LC-MS). The proteins that were up regulated during decidualisation include insulin growth factor binding protein as well as caldesmon, tropomycin, actin, tubulin, SRC substrate cortactin and calponin-1 which contribute to the re-organisation of cell cytoskeletal restructuring and remodelling. Proteins associated with cellular growth and transformation such as annexin, nuclear migration factor protein and elongation factor 1B were also up regulated. These results suggest that the process of decidualisation is complicated requiring synergy and cross-talk between structural and cell growth proteins and pathways.

108. FUNCTIONAL ROLE OF HtrA3 IN TROPHOBLAST CELL INVASION DURING HUMAN PLACENTAL DEVELOPMENT

Controlled invasion of extravillous trophoblast (EVT) through the maternal decidua is important for placental development and function. Serine protease HtrA3 is highly expressed in the decidual cells in the late secretory phase of the menstrual cycle and throughout pregnancy. It is highly expressed in first trimester in most trophoblast cell types, but not in the invading interstitial trophoblast. HtrA3 and its family members are down-regulated in a number of cancers and are proposed as tumor-suppressors. We hypothesized that HtrA3 is an inhibitor of trophoblast invasion and is down-regulated in invading EVTs, while up-regulation of decidual HtrA3 controls the process. The current study investigated HtrA3 expression in human endometrial stromal cells (HESC) during decidualization in vitro and whether HtrA3 inhibits EVT cell invasion. Stromal cells isolated from human endometrium were decidualized in vitro with estrogen, progesterone and cAMP. Quantitative RT-PCR and western showed HtrA3 mRNA and protein expression was significantly increased in decidualized HESC compared to controls. Indirect immunofluorescence showed homogeneous pattern and increase in intensity of HtrA3 staining in decidualized HESC compared to non-decidualized cells. HTR-8 cells derived from first trimester of pregnancy EVT showed higher levels of HtrA3 mRNA expression compared to other human choriocarcinoma cell lines (AC-1M88, AC-1M32, JEG-3 and BeWo). Both intracellular and extracellular HtrA3 staining was observed in HTR8 cells. Functional role of HtrA3 in cell invasion was determined in HTR-8 cells using an in vitro invasion assay. Exogenous addition of mutant HtrA3 (inhibitor) resulted in a significant increase in HTR-8 cells invading through matrigel coated membrane compared with controls. TGFβ-1 (as positive control) completely inhibited invasion of HTR-8 cells. HtrA3 is tightly regulated during decidualization of HESC in vitro. Inhibition of HtrA3 activity in trophoblastic HTR-8 cells increased invasiveness supporting its functional role during placental development.

529. PROPROTEIN CONVERTASE 6 PLAYS A CRITICAL ROLE IN MODULATING THE HUMAN ENDOMETRIAL EPITHELIUM FOR RECEPTIVITY AND IMPLANTATION

Successful embryo implantation is an important step in establishing pregnancy, requiring a healthy embryo and a receptive endometrium. Establishment of endometrial receptivity involves morphological and physiological changes initially in the endometrial epithelium, but the underlying molecular mechanisms are not fully understood. We have previously demonstrated that proprotein convertase 5/6 (PC6), a member of the proprotein convertase (PC) family, is up-regulated in the endometrium specifically at implantation in association with epithelial differentiation, in the human and monkey. PCs convert a range of precursor proteins of important functions into their bioactive forms; they are thus regarded as critical “master switch” molecules. The present study aimed to determine whether PC6 is a critical regulator in the endometrial epithelium for receptivity and implantation. We examined whether endometrial epithelial PC6 dys-regulation is associated with implantation failure in women and whether knockdown of PC6 by siRNA in human endometrial epithelial cells affects embryo adhesion in a cell culture model. Endometrial PC6 expression was assessed by immunohistochemistry in the mid-secretory phase of the menstrual cycle (receptive phase) in two unique clinical cohorts comprising women of known fertility and infertility (with no obvious gynecological disorders, and with fertile males). Endometrial epithelial PC6 levels were significantly lower in infertile vs fertile women in both cohorts. To further establish that PC6 is important for receptivity, a cell model relevant to human implantation was used involving co-culture of uterine epithelial cells with mouse embryos. The epithelial cells were stably transfected with PC6 siRNA and PC6 knock down was confirmed at the levels of mRNA, protein, and activity by real-time RT-PCR, Western blotting and activity assay respectively. Embryos readily adhered to normal epithelial cells, but the adhesion was significantly reduced in the PC6 knockdown epithelial cells. We are currently using proteomics technology to identify the pathways affected by PC6 knockdown. These results strongly suggest that PC6 plays a critical role in modulating the human endometrial epithelium for receptivity and implantation.

175. THE ROLE OF PROPROTEIN CONVERTASE 6 DURING DECIDUALIZATION: REGULATION OF BONE MORPHOGENETIC PROTEIN 2 ACTIVATION

Proprotein convertase 5/6 (PC6), a member of the proprotein convertase (PC) family, is a critical endometrial factor for implantation. PC6 is up-regulated in the endometrium specifically at implantation in association with epithelial differentiation (in human and monkey) and stromal cell decidualization (in the mouse, human and monkey). PC6 is the only PC member that was significantly up-regulated during decidualization. Knockdown of PC6 inhibits decidualization. PCs function by converting a range of important precursor proteins into their bioactive forms. One group of such proteins is the transforming growth factor beta (TGF-beta) superfamily proteins. They are first synthesized as larger biologically inactive precursors, and then are processed by PCs into their active forms. Bone morphogenetic protein 2 (BMP2) is a TGF-beta superfamily member and demonstrated to be essential for decidualization. We hypothesized that BMP2 is one of the proteins that PC6 activates during decidualization. Freshly isolated stromal cells from human endometrium were decidualized in culture with and without inhibition of PC6 activity. The full-length (precursor, non-active) and processed (activated) forms of BMP2 were determined in cellular lysates and media. The precursor form of BMP2 was reduced whereas the active form was increased during decidualization. Inhibition of PC6 activity inhibited decidualization, and this inhibition was accompanied by a total inhibition of the production of active BMP2. To further confirm the role of PC6 in activating BMP2 in decidualization, active BMP2 was added into cells and the decidualization arrest caused by PC6 inhibition was partially rescued. This study demonstrated that PC6 regulates decidualization by activating molecules such as BMP2 that are essential for decidualization.

Prediction of preeclampsia - a workshop report

Understanding the mechanisms of disease responsible for the syndrome of preeclampsia as well as early risk assessment is still a major challenge. The concentrations of circulating proteins in maternal blood such as placental growth factor, soluble vascular endothelial growth factor receptor-1 and soluble endoglin are altered weeks before the onset of clinical symptoms of the syndrome. Recently, other proteins in maternal serum, such as activin A, inhibin A, PAPP-A, and PP13 have been suggested to be of value in first trimester risk assessment. Since preeclampsia is a syndrome, it seems unlikely that a single test will predict all forms of preeclampsia. This realization has led to the formulation of a new conceptual framework suggesting that a combination of markers (biochemical and/or biophysical) may be required to conduct comprehensive risk assessment for the syndrome.

211. Proteomic identification of caldesmon as one of the physiological substrates of proprotein convertase 6 during decidualisation

We have previously demonstrated that proprotein convertase 5/6 (PC6), a member of the proprotein convertase (PC) family, is a critical endometrial factor for implantation. PC6 is upregulated in the endometrium specifically at implantation in association with epithelial differentiation (in human and monkey) and stromal cell decidualisation (in the mouse, human and monkey). Knockdown of endometrial PC6 during early pregnancy in mice in vivo led to complete failure of implantation, while blocking of PC6 production in human endometrial stromal cells in vitro inhibited decidualisation. PCs convert a range of precursor proteins of important functions into their bioactive forms; they are thus regarded as critical ‘master switch’ molecules. We hypothesise that PC6 exerts its roles in the endometrium by regulating proteins of diverse functions essential for implantation. In this study, we utilised proteomic technology and aimed to identify proteins that are specifically cleaved by PC6 in human endometrial stromal cells (HESC) during decidualisation. HESC were decidualised with cyclic AMP, the cell lysates were treated with and without recombinant human PC6-A (rPC6-A), and the 2D Differential in Gel Electrophoresis (2D DiGE) protein profiles were compared between the two treatments. We identified several proteins which were differentially cleaved following the addition of rPC6-A. Mass spectrometric analysis confirmed that the most abundant of these were caldesmon, tropomyosin-2, tropomyosin-4, hypoxia Inducible factor-1 and chloride intracellular channel-1. These proteins showed spot shifts in hPC6-A treated HESC lysates consistent with hPC6-A cleavage. western blot analysis confirmed the specific cleavage of caldesmon by PC6 in HESCs, and immunohistochemical analysis showed co-localisation of caldesmon and PC6 in decidual cells in human endometrial tissue. Given that caldesmon is a structural protein previously found to be involved in actin filament reorganisation, our results strongly suggest that PC6 is a mediator of structural remodelling of stromal cells during decidualisation in the endometrium.

212. Specific targeting of uterine proprotein convertase 6 (PC6) facilitates the development of dual function contraception

Proprotein convertase 6 (PC6), is a key player during embryo implantation in humans and mice. We have previously shown that PC6 is essential for decidualisation in the mouse and knockdown of endometrial PC6 leads to implantation failure. The PC family of proteases, including PC6, are necessary for transmission of human immunodeficiency virus (HIV). It has been postulated that inhibition of PC activity could prevent HIV infection. We hypothesise that PC6 is a prospective target for the development of a dual role contraceptive for women to avoid pregnancy and protect from HIV infection. The aim of this study is to evaluate if a PC6 inhibitor that is capable of preventing HIV transmission can block implantation in mice. We used a generic PC peptide substrate to assess the potency of the inhibitor to block PC6 activity in vitro. The substrate releases a fluorochrome when cleaved by PC6; no fluorescent signals were observed in samples when inhibitor concentrations were 10μM or higher. We then gauged inhibitor uptake by the uterus over 24 h in mice by two delivery routes; intrauterine injection (IU) and vaginal delivery (VD) with a neutral gel. Uptake was tracked with a FITC-conjugated inhibitor at 50μM (IU) and 500μM (VD). Strong fluorescent signals were seen at 2, 4, 6 and 24 h at sites of endometrial PC6 activity in the IU and VD groups. Administration of a 50μM dosage (20μl) to the uterine lumen (IU) caused a significant reduction (P = 0.002) in the number of implantation sites compared with controls (saline only) when treated between 2000–2100 on E3.75. The inhibitor's ability to block uterine PC6 activity and implantation via VD was assessed and to date outcomes have suggested that correct timing is crucial to prevent implantation and decidualisation. These outcomes show the potential of the inhibitor to block implantation in mice.

Pro-protein convertases (PCs) other than PC6 are not tightly regulated for implantation in the human endometrium

Pro-protein convertases (PCs) are a family of serine proteases (furin, PC1/3, PC2, PACE4, PC4, PC5/6, PC7/8) responsible for post-translational processing and activation of inactive precursors of many regulatory proteins. Endometrial PC6 is critical for implantation in mice and for decidualization of human endometrial stromal cells (ESCs). This study investigated the endometrial expression of other PCs during the menstrual cycle and early pregnancy to elucidate potential redundancies. Furin, PC4, PACE4, and PC7 along with PC6 transcripts were detected in total endometrial RNA, whereas PC1 and PC2 transcription levels were negligible. Quantitative RT-PCR demonstrated highest levels of furin mRNA during menstruation and lowest levels during the proliferative phase. Furin protein was immunolocalized in endometrial luminal and glandular epithelia, stromal fibroblasts, endothelia, and leukocytes. PACE4 and PC7 proteins were also immunodetected in endometrial stroma and glands. Total furin, PC7, and PACE4 proteins were constitutive in both stromal and glandular compartments throughout the cycle and during first trimester pregnancy. Furthermore, Furin and PC7 transcription was unaltered during decidualization of ESCsin vitroin contrast to PC6 which is significantly up-regulated during decidualization. Thus, whereas PC6 is tightly regulated during endometrial preparation for implantation, furin, PACE4, and PC7 are constitutively expressed in human endometrium, but must be considered if PC6 is to be targeted for manipulation of fertility.

HtrA3, a serine protease possessing an IGF-binding domain, is selectively expressed at the maternal-fetal interface during placentation in the mouse

Hemochorial placentation involves highly regulated interactions between fetal- and maternal-derived cells. HtrA3, a novel serine protease containing an insulin-like growth factor (IGF) binding domain, was previously shown to increase during early pregnancy in the mouse uterus, being dramatically upregulated post-implantation. The present study examined the regulation of HtrA3 gene in the mouse uterus from post-implantation to late gestation. Both mRNA and protein of HtrA3 were localized specifically in the maternal decidua. In contrast, HtrA3 expression was below detection in trophoblasts, including the giant cells that are in direct contact with the decidua. This pattern persisted from the early stages of placentation to near term. The level of decidual HtrA3 mRNA and its protein gradually decreased as the placenta matured. In the decidua, only the maternal decidual cells, but not blood vessels or uterine NK cells that are present in large numbers, were positive for HtrA3. The specific localization of a protease possessing an IGF-binding domain at the maternal-fetal interface suggests that HtrA3 plays a critical role in mediating maternal decidual remodelling and maintenance, likely in association with the IGF system, in placental development and function.

211. Expression and cellular localization of HTRA3 protease during placental development in mice

Placental development in mice involves highly regulated interactions between fetal- and maternal-derived cells. We have previously cloned a novel serine protease (HtrA3) containing an insulin-like growth factor (IGF) binding domain, which was upregulated during pregnancy, especially post-implantation in the mouse uterus.1 The present study examined HtrA3 regulation during placental development in mice, in particular, its expression in the different compartments of the placenta. Expression of mRNA was determined by Northern blot analysis in implantation units containing the decidua, placenta and fetus (day 8.5 to near-term). A specific HtrA3 antibody was generated, affinity-purified and used for Western blot analysis and immunohistochemistry. Both mRNA and protein of HtrA3 were identified specifically in the maternal decidua. In contrast, HtrA3 expression was below detection in trophoblasts, including the giant cells that are in direct contact with the decidua. This pattern persisted from the early stages of placentation to near term. The level of decidual HtrA3 mRNA and its protein gradually decreased as the placenta matured. In the decidua, only the maternal decidual cells, but not blood vessels or uterine NK cells that are present in large numbers, were positive for HtrA3. The specific localization of HtrA3, a protease possessing an IGF binding domain at the maternal–fetal interface, suggests that this protein plays an important role in mediating maternal decidual remodelling and maintenance, probably in association with the IGF system, in placental development and function. (1)Nie et al. (2003). Mol. Hum. Reprod.

240. Spatial and temporal expression pattern of furin in the human endometrium

Furin is a proprotein convertase (PC) implicated in the endoproteolytic maturation of inactive protein precursors of growth factors, hormones, receptors, and viral envelope glycoproteins.1 Two functionally active forms of furin, one membrane-bound containing a C-terminal transmembrane domain (TD) and a cytoplasmic tail (CT), and one soluble without the TD and CT, have been characterised. We have previously shown that PC6, one of the PCs closely related to furin, is expressed in the human endometrium and is closely associated with decidualization of stromal cells during implantation.2 Although furin is ubiquitously expressed, its expression in the human endometrium is unknown. In this study, we investigated the spatial and temporal expression pattern of furin in the human endometrium using RT-PCR and immunohistochemistry. While furin expression is detected throughout the menstrual cycle and during early pregnancy, lowest mRNA levels are seen during the proliferative phase. Using an antibody directed against the C-terminus of the membrane bound form, furin is detected in the stroma, glandular and luminal epithelium, as well as in endothelia and neutrophils throughout the menstrual cycle and during early pregnancy. In the stroma, highest levels of furin are present during menstruation (n = 3), they are also high during the proliferative phase (n = 4), but significantly lower levels are detected during the secretory phase (n = 10, P < 0.05, Tukey HSD). In the first trimester decidua, furin is present in well decidualised stromal cells. The overall expression pattern of furin is different to that of PC6; in particular, furin expression is associated only with well decidualized stromal cells whereas PC6 is involved in the initial stages of decidualization. These data suggest that furin and PC6 play different roles in the human endometrium, especially during embryo implantation. (1)Nakayama K. (1997). Biochem. J. 327, 625–635.(2)Nie et al. (2005). Biol. Reprod. 72, 1029–1036.

228.Progestin-induced proprotein convertase 6 is necessary for decidualisation of human endometrial stromal cells in vitro

Decidualisation of human endometrium is an essential preparative event for successful establishment of pregnancy, and involves dramatic morphological and functional differentiation of the human endometrial stromal cells (ESCs). Proprotein convertase 6 (PC6) plays an important role in the processes of stromal cell decidualisation and embryo implantation in the mouse. PC6 is a member of the proprotein convertase family responsible for processing precursor proteins to their bioactive forms by selective proteolysis. In the present study we investigated the regulation of PC6 mRNA and protein expression in ESCs during decidualisation in vitro, and established a function for PC6 in decidualisation using morpholino antisense oligonucleotides (MOs). PC6 mRNA levels in ESCs during decidualisation were determined using quantitative real-time RT-PCR. 17β-oestradiol (E) plus medroxy-progesterone acetate (P) caused a significant increase in PC6 mRNA during decidualisation, whereas E alone did not increase PC6 mRNA expression. Consistent with the results of real-time PCR, much stronger PC6 immunostaining was observed in the cytoplasm of E plus P-treated ESCs (decidualised) compared to the E-treated ESCs (non-decidualised) on Day 12 of culture. This strong staining for PC6 was abolished by cotreatment with ZK 98299, a progesterone receptor antagonist. To investigate whether the induction of PC6 was necessary for decidualisation in vitro, MOs were used to block PC6 synthesis in cultured ESCs. PRL production, a typical marker for decidualisation, was significantly attenuated in decidualing ESCs following treatment with PC6 MOs in comparison to controls. These results suggest that PC6 plays a key role for decidualisation in human ESCs.

284.Expression of HtrA1, 2 and 3 in human endometrial cancer

The mammalian HtrA family consists of serine proteases with distinct domains homologous to the bacterial high temperature requirement factor (HtrA). Three human HtrA members have been reported: HtrA1 (PRSS11 or L56), HtrA2 (OMI) and HtrA3 (PRSP). The function of HtrA1 is not well characterised, but it has been shown to be downregulated in malignant tissues (1–3) indicating that the downregulation of HtrA1 is associated with cancer progression. HtrA2 regulates apoptosis by interacting with X-linked inhibitors of apoptosis (XIAP) thus preventing the caspase-inhibitory function of XIAP (4). The function of newly identified HtrA3 is not known, however it shares a high degree of sequence and domain homologies with HtrA1 and may therefore share a functional similarity with HtrA1 (5). Endometrial cancer (EC) is a prevalent gynaecological cancer, commonly affecting women after menopause. In this study we examined the expression of HtrA1, 2 and 3 in EC. Reverse transcriptase-PCR (semi-quantitative) analysis showed decreased mRNA expression of both HtrA1 and HtrA3, but no significant change for HtrA2, in EC tissue samples compared to normal endometrium. We then determined the protein level of expression and the cellular localisation of all three HtrA members in EC progression using immunohistochemistry. HtrA1 and HtrA3 showed a similar pattern of expression and both decreased dramatically with the progression of cancer from grade 1 through to 3. Surprisingly, HtrA2 protein expression was also decreased with cancer progression, but the decline was not as dramatic as that for HtrA1 and HtrA3. Interestingly, considerably less staining was observed for all three HtrA proteins in grade 3 cancer tissues. These data suggest that decreased expression of HtrA proteins, particularly HtrA1 and HtrA3, is associated with the progression of endometrial cancer. (1) Nie, G., Hampton, A., Li, Y., Findlay, J., Salamonsen, L.A. (2003) Identification and cloning of two isoforms of human high-temperature requirement factor A3 (HtrA3), characterization of its genomic structure and comparison of its tissue distribution with HtrA1 and HtrA2. Biochem. J. 371, 39–48. (2) van Loo, G., van Gurp, M., Depuydt, B., Srinivasula, S.M., Rodriguez, I., Alnemri, E.S., Gevaert, K., Vandekerckhove, J., Declercq, W., Vandenabeele, P. (2002) The serine protease OMI/HtrA2 is released from mitochondria during apoptosis. OMI interacts with caspase-inhibitor XIAP and induces enhanced caspase activity. Cell Death Diff. 9, 20–26. (3) Chien, J., Staub, J., Hu, S., Erickson-Johnson, M.R., Couch, F.J., Smith, D.I., Crowl, R.M., Kaufmann, S., Shridhar, V. (2004) A candidate tumour supressor HtrA1 is down-regulated in ovarian cancer. Oncogene 23, 1636–1644. (4) Shridhar, V., Sen, A., Chien, J., Staub, J., Avula, R., Kovats, S., Lee, J., Lillie, J., Smith, D.I. (2002) Identification of underexpressed genes in early- and late-stage primary ovarian tumours by suppression subtraction hybridization. Cancer Res. 62, 262–270. (5) Baldi, A., De Luca, A., Morini, M., Battista, T., Felsani, A., Baldi, F., Catricala, C., Amantea, A., Noonan, D. M., Albini, A., Ciorgio, P., Lombardi, D., Paggi, M. G. (2002) The HtrA1 serine protease is down-regulated during human melanoma progression and represses growth of metastatic melanoma cells. Oncogene 21, 6684–6688.

014.Novel uterine genes in regulation of embryo implantation

Implantation of the embryo into the maternal endometrium is the first and critical step leading to the establishment of a pregnancy. It has been well established that only during the 'window' of implantation, a limited time span when the uterine environment is receptive, can a blastocyst successfully implant into the uterus. The development of uterine receptivity is accompanied by remarkable morphological and physiological changes in the endometrium, and this is primarily driven by the coordinated effects of the ovarian steroid hormones. Uterine tissue remodelling during implantation also contributes significantly to the development of the placenta. Insufficient uterine remodelling causes implantation failure and infertility. To date, the exact molecular events occurring in the uterus during the establishment of receptivity and at the actual site of implantation are still not well understood. We used the mouse as a model and identified a number of previously unrecognised molecules that are uniquely regulated in the early stages of implantation: one of these is proprotein convertase 6 (PC6). The potential importance of these genes and their products in modulating fertility in the primate, including the human, was demonstrated by their unique spatial and temporal expression in the endometrium of human and rhesus monkey during the phase of uterine receptivity and at implantation. The importance of the genes for implantation was ultimately confirmed by functional studies in vivo using morpholino antisense oligonucleotides. These molecules will be discussed in terms of their identity, expression and functions.

Complex regulation of decidualization: a role for cytokines and proteases--a review

Decidualization of the endometrial stroma is a precondition for successful establishment of pregnancy. While the local molecular mechanisms driving decidualization are still largely unknown, a number of autocrine/paracrine factors have been identified as differentiation factors in this process. These include the cytokines, interleukin 11, activin A and monoclonal non-specific suppressor factor beta (MNSFbeta). Furthermore, locally produced proteases, including proprotein convertase 6 and matrix metalloproteinases, enable expansion of the tissue and processing of regulatory molecules. This article reviews recent work from our laboratory on the roles of these factors in decidualization.

Genes involved in implantation

The endometrium is normally a hostile environment for an embryo, except for a short phase in each reproductive cycle known as the 'window of receptivity'. The precise molecular events involved in this transformation are not well understood. Application of state-of-the-art techniques of the 1990s has identified some of the genes involved, which are reviewed here. Mice with a null mutation in either the gene for leukemia inhibitory factor or the interleukin-11 receptor alpha chain are infertile, owing in both cases to a failure of embryo implantation. Both of these genes are expressed in the human endometrium with patterns suggesting a role in human fertility. The technique of RNA differential display has been applied to a comparison of the expression of genes at implantation sites v. inter-implantation sites in the mouse uterus on the first day of implantation, and has defined additional genes whose products may be important for this process. Among these are the calcium-binding protein D9K, the monoclonal non-specific suppressor factor beta, and the splicing factor SC35. The major challenge is to determine whether manipulation of such genes can increase or decrease endometrial receptivity in humans.