Melatonin suppresses tumor proliferation and metastasis by targeting GATA2 in endometrial cancer.

Endometrial cancer (EC) is a reproductive system disease that occurs in perimenopausal and postmenopausal women. However, its etiology is unclear. Melatonin (MT) has been identified as a therapeutic agent for EC; however, its exact mechanism remains unclear. In the present study, we determined that GATA-binding protein 2 (GATA2) is expressed at low levels in EC and regulated by MT. MT upregulates the expression of GATA2 through MT receptor 1A (MTNR1A), whereas GATA2 can promote the expression of MTNR1A by binding to its promoter region. In addition, in vivo and in vitro experiments showed that MT inhibited the proliferation and metastasis of EC cells by upregulating GATA2 expression. The protein kinase B (AKT) pathway was also affected. In conclusion, these findings suggest that MT and GATA2 play significant roles in EC development.

OPN up-regulated proliferation and invasion of head and neck squamous cell carcinoma through the p38MAPK signaling pathway.

OBJECTIVE: Osteopontin (OPN) is aberrantly expressed in various tumors. However, its role and detailed mechanisms in head and neck squamous cell carcinoma (HNSCC) have not been extensively described. STUDY DESIGN: Expression of OPN in HNSCC was examined at the gene and protein levels. The effect of cell proliferation ability was examined by Cell Counting Kit-8, colony formation assay, cell invasiveness by Transwell assay, the effect of OPN on protein expression of Capase-3 and Bcl2 by Western blotting, and the expression of p38MAPK signaling pathway by p38MAPK inhibitor SB203580. RESULTS: We found that OPN expression was higher in human HNSCC tissues than in adjacent tissues. Osteopontin may regulate the proliferation and invasion of HNSCC cells through the p38-MAPK signaling pathway. DISCUSSION: Our study identifies an important role for OPN in HNSCC and further demonstrates that it may regulate the proliferation and invasion of HNSCC cells by activating the p38-MAPK signaling pathway. Osteopontin may be a promising prognostic and diagnostic indicator and a potential target for cancer therapy.

OPN N-glycosylation promoted bone destruction.

OBJECTIVES: Exploring the role of OPN N-glycosylation in osteoblasts and osteoclasts. METHODS: Immunohistochemistry was used to detect the expression of OPN in mice with apical periodontitis. The asparagine at position 79 of the OPN protein was mutated to glutamine, and the above plasmids were transfected into osteoblasts and osteoclasts. The effect of OPN N-glycosylation on proliferation of osteoblasts and osteoclasts was detected by CCK8 assays. Western blotting was used to detect the expression of OPN N-glycosylation on osteoclasts and osteoblasts. Detection of N-glycosylation of OPN activated the NF-κB signaling pathway to regulate osteoblasts and osteoclasts. RESULTS: OPN increased the expression in a mice model of apical periodontitis. The expression curve of OPN resembled a reverse V shape. The OPN N-glycosylation site was identified as 79 by MS. N-glycosylation of OPN promoted the proliferation of osteoclasts. But the N79 glycosylation site of mutant OPN could not increase the proliferation of osteoblasts. OPN N-glycosylation modulated the expression of osteoclast- and osteoblast-associated factors through the NF-κB signaling pathway. N-glycosylation of OPN promoted nuclear translocation of NF-κB in osteoclasts and osteoblasts. CONCLUSIONS: The N-glycosylation site of OPN is 79. N-glycosylation of OPN played an important role in the biological function of OPN protein.

Reprogramming lipid metabolism as potential strategy for hematological malignancy therapy.

Hematological malignancies are one of the most lethal illnesses that seriously threaten human life and health. Lipids are important constituents of various biological membranes and substances for energy storage and cell signaling. Furthermore, lipids are critical in the normal physiological activities of cells. In the process of the lethal transformation of hematological malignancies, lipid metabolism reprogramming meets the material and energy requirements of rapidly proliferating and dividing tumor cells. A large number of studies have shown that dysregulated lipid metabolism, commonly occurs in hematological malignancies, mediating the proliferation, growth, migration, invasion, apoptosis, drug resistance and immune escape of tumor cells. Targeting the lipid metabolism pathway of hematological malignancies has become an effective therapeutic approach. This article reviews the oncogenic mechanisms of lipid metabolism reprogramming in hematological malignancies, including fatty acid, cholesterol and phospholipid metabolism, thereby offering an insight into targeting lipid metabolism in the treatment of hematological malignancies.

Ibrutinib Inhibits Angiogenesis and Tumorigenesis in a BTK-Independent Manner.

BTK inhibitor (BTKi) Ibrutinib carries an increased bleeding risk compared to more selective BTKis Acalabrutinib and Zanubrutinib, however, its impact on vascular endothelium remains unknown. In this study, we found that Ibrutinib induced stronger cytotoxic effect on endothelial cells than Zanubrutinib, however, Acalabrutinib cytotoxicity was extremely weak. RNA-seq, followed by KEGG analysis and quantitative RT-PCR validation, was conducted to identify the differential apoptotic target genes of BTKis, leading to their distinct cytotoxic effects on endothelial cells, which showed that Ibrutinib and Zanubrutinib dramatically modulated the expression of critical apoptotic genes, GADD45B, FOS, and BCL2A1, among which FOS and GADD45B were upregulated more significantly by Ibrutinib than Zanubrutinib, however, Acalabrutinib downregulated BCL2A1 moderately and was not able to modulate the expression of FOS and GADD45B. Next, we performed in vitro angiogenesis assays and found that Ibrutinib was more able to induce endothelial dysfunction than Zanubrutinib via stimulating more BMP4 expression, however, Acalabrutinib had no such effect. Especially, the capacity of Ibrutinib to induce endothelial dysfunction can be antagonized by targeting BMP4. Accordingly, Ibrutinib, as an angiogenesis inhibitor, inhibited ovarian and breast cancer progression in vivo. Collectively, our findings addressed a novel molecular basis underlying Ibrutinib-induced endothelial cell dysfunction and suggested the potential application of Ibrutinib to treat angiogenesis-dependent cancers.

O-GlcNAc modification mediates aquaporin 3 to coordinate endometrial cell glycolysis and affects embryo implantation.

Introduction: O-linked ß-D-N-acetylglucosamine (O-GlcNAc) modification is a post-translational modification in which a single O-GlcNAc is added to serine or threonine residues in nuclear, cytoplasmic, and mitochondrial proteins, and is involved in a variety of physiological processes. Objectives: In the present study, the role of O-GlcNAcylation in embryo implantation was evaluated. Furthermore, whether O-GlcNAcylation is involved in orchestrating glucose metabolism to influence endometrial cell physiological functions was investigated. Methods: Different endometrial tissues were detected using immunohistochemistry. Pregnant mouse models were established to verify molecular expression. O-GlcNAc transferase and aquaporin 3 (AQP3) knockdown were used to detect embryo implantation efficiency in vitro and in vivo. Western blotting and immunofluorescence were used to detect protein expression and stability. Dual luciferase reporter assay and chromatin immunoprecipitation (ChIP) were used to verify the binding transcription factor. Glycolysis was detected using bioenergy analyzer, and metabolites were analyzed using isotope 13C-labeled LC-MS. Metabolic-related genes were determined using RNA sequencing. Results: Activation of endometrial hexosamine biosynthetic pathway (HBP) caused elevated O-GlcNAcylation during the window of implantation, affecting endometrial cell function and embryo implantation. Specifically, elevated O-GlcNAcylation increased glucose uptake via glucose transporter 1 (GLUT1) leading to glucose metabolic flow into the pentose phosphate pathways and HBP, which regulate the metabolic reprogramming of endometrial cells. Furthermore, O-GlcNAcylation mediated the intracellular transport of glycerol to support and compensate for glycolysis through regulation of AQP3. Unexpectedly, elevated AQP3 also increased glucose uptake via GLUT1. These processes maintained higher metabolic requirements for endometrial physiology. Furthermore, the transcription factor SP1 specifically bound to the AQP3 promoter region, and O-GlcNAcylation of SP1 increased its stability and transcriptional regulation of AQP3 which is associated with O-GlcNAcylation of SP1. Conclusion: Overall, O-GlcNAcylation regulated glucose metabolism in endometrial cells, and AQP3-mediated compensation provides new insights into the communication between glycolysis and O-GlcNAcylation.

miR-30a targets STOX2 to increase cell proliferation and metastasis in hydatidiform moles via ERK, AKT, and P38 signaling pathways.

BACKGROUND: A hydatidiform mole is a condition caused by abnormal proliferation of trophoblastic cells. MicroRNA miR-30a acts as a tumor suppressor gene in most tumors and participates in the development of various cancers. However, its role in hydatidiform moles is not clear. METHODS: Quantitative real-time reverse transcription PCR was used to verify the expression level of miR-30a and STOX2 (encoding storkhead box 2). Flow cytometry assays were performed to detect the cell cycle in cell with different expression levels of miR-30a and STOX2. Cell Cycle Kit-8, 5-ethynyl-2'-deoxyuridine, and colony formation assays were used to detect cell proliferation and viability. Transwell assays was used to test cell invasion and migration. Dual-luciferase reporter assays and western blotting were used to investigate the potential mechanisms involved. RESULT: Low miR-30a expression promoted the proliferation, migration, and invasion of trophoblastic cells (JAR and HTR-8). Dual luciferase assays confirmed that STOX2 is a target of miR-30a and resisted the effect of upregulated miR-30a in trophoblastic cells. In addition, downregulation of STOX2 by miR-30a could activate ERK, AKT, and P38 signaling pathways. These results revealed a new mechanism by which ERK, AKT, and P38 activation by miR-30a/STOX2 results in excessive proliferation of trophoblast cells in the hydatidiform mole. CONCLUSIONS: In this study, we found that miR-30a plays an important role in the development of the hydatidiform mole. Our findings indicate that miR-30a might promote the malignant transformation of human trophoblastic cells by regulating STOX2, which strengthens our understanding of the role of miR-30a in regulating trophoblastic cell transformation.

Paired-like homeodomain transcription factor 2 affects endometrial cell function and embryo implantation through the Wnt/ß-catenin pathway.

The successful implantation of embryos is crucial for pregnancy in mammals. This complex process is inevitably dependent on the development of the endometrium. The paired-like homeodomain transcription factor 2 (PITX2) is involved in a variety of biological processes, but whether it is involved in embryo implantation has not been reported. In this study, we aimed to investigate uterine expression and regulation of PITX2 during implantation. We found that PITX2 was elevated in the human endometrium in the secretory phase. The results of the pregnant mouse models showed that PITX2 expression was spatiotemporal in mouse endometrial tissue throughout peri-implantation period, and it was significantly upregulated at the time of implantation. Interestingly, PITX2 was mainly localized to the glandular epithelium cells on D2.5-3.5 of pregnancy, while D5.5-6.5 was largely expressed in stromal cells. In vitro, PITX2 regulated endometrial cells proliferation, migration, invasion, and other functions through the Wnt/ß-catenin signaling pathway. In addition, a significant decrease in the rate of embryo implantation was observed after injecting PITX2 small interfering RNA into the uterine horn. These results demonstrate the effects of PITX2 on the physiological function of endometrial cells and embryo implantation, suggesting a role in the endometrial regulatory mechanism during implantation.

Therapeutic effect of thalidomide combined with temozolomide and three-dimensional conformal radiotherapy for patients with high-grade gliomas after operation.

PURPOSE: To explore the efficacy and safety of 125 I radioactive seed implantation combined with intermittent hormonal therapy (IHT) in the clinical treatment of moderate- and high-risk non-metastatic prostate cancer. METHODS: A total of 136 patients were divided into the observation group (n=68) and the control group (n=68). In the observation group, 125I radioactive seed implantation was performed, bicalutamide capsules were taken orally immediately after operation, and leuprorelin was injected from 1 week after operation. In the control group, IHT alone was administered. The level of serum prostate specific antigen (PSA), maximum urine flow rate (Q max ) and international prostate symptom scale (IPSS) score were compared between the two groups before and after treatment. Moreover, the overall survival (OS), tumor-specific survival (TSS), distant metastasis-free survival (DMFS) and progression-free survival (PFS) of patients were recorded. RESULTS: There were no statistically significant differences in the PSA level, Q max and IPSS score between the two groups before treatment (p>0.05). At 6, 12 and 24 months after treatment, the level of PSA in the observation group was significantly lower than in the control group (p=0.005, p<0.001, p<0.001). At 24 months after treatment, Q max in the observation group was significantly higher than in the control group (p=0.025). At 12 and 24 months after treatment, the IPSS score in the observation group was significantly lower than that in the control group (p=0.013, p=0.002). During the follow-up period, the intermission time of hormonal therapy and PFS time in the observation group were obviously longer than those in control group (p<0.001). In the two groups, OS was 97.1% and 94.1%, TSS was 95.6% and 92.6%, DMFS was 82.4% and 66.2%, and PFS was 72.1% and 51.5%, respectively. It can be seen that OS and TSS had no statistically significant differences between the two groups (p=0.405, p=0.496), while DMFS and PFS in the observation group were remarkably superior to those in the control group (p=0.037, p=0.022). CONCLUSIONS: 125 I seed implantation combined with IHT is safe and effective in the clinical treatment of patients with moderate- and high-risk non-metastatic prostate cancer. Compared with the IHT alone, the combination therapy can significantly prolong the intermission time of hormonal therapy and effectively control the progression of disease.

Progesterone Regulates Glucose Metabolism Through Glucose Transporter 1 to Promote Endometrial Receptivity.

Successful embryo implantation requires receptive endometrium, which is conducive to the process of embryo recognition, adhesion, and invasion within a certain period of time and is inseparable from the dynamic interaction between 17ß-estradiol (E2) and progesterone (P4). Proper glucose metabolism is critical for the profound physiological changes in the endometrium entering the receptive state. And glucose transporters (GLUTs) are responsible for intracellular uptake of glucose and are the first step in glucose metabolism. Prior literature has reported the presence of GLUTs in the endometrium. However, we still do not understand the specific mechanisms of this process. In this study, we identified the effect of P4 on glucose transporter 1 (GLUT1) using in vivo animal models and determined the regulation of glucose metabolism by P4 in cells. We highly suspect that this pregnancy failure may be due to reduced GLUT1-mediated glucose metabolism, resulting in a decrease in endometrial receptivity caused by an inadequate energy supply and synthesis of substrate. Here, we propose a possible mechanism to explain how embryo implantation is affected by P4 and glucose utilization under abnormal endometrial conditions.

MiR-30a-5p inhibits proliferation and metastasis of hydatidiform mole by regulating B3GNT5 through ERK/AKT pathways.

Hydatidiform moles are gestational trophoblastic disease. They are abnormal proliferations of trophoblast cells that have the potential to become cancerous. miR-miR30a-5p is a tumour suppressor that participates in the development of numerous diseases. However, the role of miR-30a in hydatidiform moles and the mechanisms underlying its effects are presently unclear. This study explored the levels of miR-30a and B3GNT5 expression in human hydatidiform mole tissue. The results showed that miR-30a and B3GNT5 were differentially expressed in normal placenta and hydatidiform mole, and miR-30a decreased cell proliferation, invasion and migration in trophoblast cell lines. Upon further examination, it was confirmed that miR-30a directly targeted the 3'untranslated region of B3GNT5 using a dual-luciferase assay. The results of the present study also revealed that miR-30a reduced the proliferation, invasion and migration ability in JAR and BeWo cells by regulating B3GNT5, which may inactivate the ERK and AKT signalling pathways. This study demonstrated that miR-30a was a novel target B3GNT5 that serves an important role in the development of hydatidiform moles, suggesting that miR-30a may serve as a novel potential biomarker or useful diagnostic and therapeutic tool for hydatidiform moles in clinical settings.

Therapeutic effect of thalidomide combined with temozolomide and three-dimensional conformal radiotherapy for patients with high-grade gliomas after operation.

PURPOSE: Purpose: To investigate the clinical therapeutic effect and safety of thalidomide combined with temozolomide (TMZ) and three-dimensional conformal radiotherapy for patients with high-grade gliomas after operation. METHODS: Methods: The clinical data of 108 patients with high-grade gliomas undergoing operation in our hospital from September 2014 to December 2016 were retrospectively analyzed, of which 54 received thalidomide combined with TMZ and three-dimensional conformal radiotherapy (thalidomide group) and 54 received TMZ combined with three-dimensional conformal radiotherapy (control group). The clinical data of all patients were collected, and the short-term therapeutic effect, adverse reactions after treatment and quality of life scores were compared between the two groups of patients. Thereafter, the level of serum immune factors of the patients was recorded, and the overall survival (OS) rate and progression-free survival (PFS) rate of the patients were followed up and recorded. RESULTS: Results: The therapeutic effect was evaluated in all the patients at 1 month after treatment. It was found that the overall response rate (ORR) in thalidomide group [68.5% (37/54)] was markedly higher than that in control group [44.4% (24/54)] (p=0.012), but the difference in the disease control rate (DCR) between thalidomide group [92.6% (50/54)] and control group [83.3% (45/54)] was not statistically significant (p=0.139). After treatment, the scores of 36-Item Short Form Health Survey (SF-36) evaluating the quality of life in thalidomide group were higher than that in control group, in which the physical function score was statistically significantly different between the two groups (p=0.028), whereas the scores of the other items did not statistically significantly differ between the two groups (p>0.05). Following treatment, the levels of serum hepatocyte growth factor (HGF), tumor necrosis factor-alpha (TNF-α), interleukin (IL)-6, IL-17, vascular endothelial growth factor (VEGF) and epidermal growth factor (EGF) were remarkably reduced in the two groups of patients, and these indexes in thalidomide group were lower than those in control group after treatment. Among them, HGF (p=0.069), TNF-α (p=0.076), IL-6 (p=0.149) and IL-17 (p=0.114) showed no statistically significant differences, but VEGF and EGF were statistically significantly different between the two groups (p<0.001). Moreover, adverse reactions were mainly manifested as myelosuppression, nausea and vomiting, constipation, liver function injury, drowsiness and neurotoxicity (grade I-II in most cases), which returned to normal after symptomatic treatment. Besides, the incidence rate of drowsiness of the patients in thalidomide group was notably lower than that in control group (p=0.029), but the difference in the incidence rate of other manifestations was not statistically significant (p>0.05). Additionally, the follow-up results manifested that the median OS was (16.1±3.6) months, (12.8±3.9) months, respectively, and the median PFS was (9.0±3.2) months and (12.3±3.4) months, respectively, in thalidomide group and control group. Furthermore, log-rank test revealed that the patients in thalidomide group had longer OS (p=0.025) and PFS (p=0.040) than those in control group. CONCLUSIONS: Conclusions: The application of thalidomide combined with TMZ and three-dimensional conformal radiotherapy for high-grade glioma patients after operation can prominently enhance the clinical therapeutic effect, improve patient quality of life, prolong survival, and produce tolerable adverse reactions.

O­GlcNAc modification influences endometrial receptivity by promoting endometrial cell proliferation, migration and invasion.

O­linked ß­N­acetylglucosamine (O­GlcNAc) modification is a dynamic post­translational modification process that is involved in many crucial biological processes, including cell cycle regulation, nutrient metabolism and extracellular signaling. This dynamic modification is dependent on the ambient glucose concentration and is catalyzed and removed by O­GlcNAc transferase (OGT) and O­GlcNAcase (OGA), respectively. The present study aimed to determine the role of O­GlcNAcylation during embryo implantation by inhibiting or enhancing its function and expression. The results revealed that the expression of O­GlcNAc­modified proteins in the human secretory endometrium was higher than that of the endometrium during the proliferative phase, as determined via western blotting and immunohistochemistry. Additionally, the level of endometrial O­GlcNAc modification increased gradually from the pre­receptive to the receptive phase, which was then decreased during the non­receptive phase. In endometrial cells, RNA interference was utilized to reduce the expression of two key O­GlcNAc synthesis and decomposition enzymes, OGT and OGA, to indirectly increase or decrease levels of O­GlcNAc modification. The results revealed that increasing the level of O­GlcNAc modification enhanced cellular proliferation, migration, invasion and adhesion, thereby promoting embryo implantation. It is hypothesized that O­GlcNAc modification serves an important role in the regulation of endometrial receptivity and embryo implantation. The results of the present study may have important implications for the understanding of female fertility and may help improve infertility treatments.

miR-196b inhibits cell migration and invasion through targeting MAP3K1 in hydatidiform mole.

MicroRNAs (miRNAs) are a class of small non-coding RNAs that are closely associated with carcinogenesis. Accumulating data indicate that miR-196b participates in the development of various types of cancers. However, the role of miR-196b in the formation of hydatidiform mole (HM) is still unclear. Our previous studies have demonstrated that miR-196b levels were decreased in JAR and BeWo cells and in HM tissue samples, as demonstrated by RT-PCR analysis. Furthermore, we discovered that overexpression of miR-196b in JAR and BeWo cells inhibited cellular proliferation, migration and invasion, as shown by Cell counting kit-8 (CCK-8) and transwell assays, respectively. Subsequently, we explored the interaction of miR-196b with its target gene in human choriocarcinoma cell lines. MAP3K1 is a target gene predicted by bioinformatic analysis that was previously shown to exhibit reduced expression levels following treatment with miR-196b in JAR and BeWo cells. We demonstrated that MAP3K1 was a direct target of miR-196b using the dual-luciferase reporter assay in Hela cells. In summary, the present study demonstrated that miR-196b suppressed proliferation, migration and invasion of human choriocarcinoma cells by inhibiting its transcriptional target MAP3K1. miR-196b and MAP3K1 may be considered potential targets for the clinical treatment of HM.

The potential role of Annexin 3 in diapause embryo restart of Artemia sinica and in response to stress of low temperature.

Annexins are highly conserved and ubiquitous in various somatic cell types. They are involved in membrane transport and a range of calcium-regulated activities on the cell membrane surface, including vesicular transport, membrane fusion in exocytosis, signal transduction, and formation of calcium channels. They also regulate inflammatory response, cell differentiation, and interaction between cytoskeletal proteins. In this study, for the first time, an ANX3 gene from Artemia sinica ( As-anx3) was cloned. The As-anx3 full-length complementary DNA comprises 1,024 bp and has a 948 bp open reading frame encoding a 315-amino-acid polypeptide with four ANX domains. The profiles of both As-ANX3 mRNA and protein expression exhibited peaks at the 0 hr stage and had the same significant downregulation trend throughout the post-diapause embryo development stage. The ERK1/2, the phosphorylation levels of ERK1/2, and cell cycle-related protein (CDK4) expressions were analyzed by western blot analysis. The results showed that CDK4 presented a significantly ascending trend from 0 and 40 hr, although the phosphorylation levels of ERK1/2 did not increase significantly. The transcriptional and protein expressions of As-ANX3 were highly upregulated when the temperature was lowered from 25 to 15°C, but the expressions showed a gradual downward trend when the temperature was further lowered to 5°C. These results indicated that As-ANX3 plays a crucial role in restarting diapause and low-temperature stress in A. sinica.

Fucoxanthin inhibits tumour-related lymphangiogenesis and growth of breast cancer.

Tumour lymphangiogenesis plays an important role in promoting the growth and lymphatic metastasis of tumours. The process is associated with cell proliferation, migration and tube-like structure formation in lymphatic endothelial cells (LEC), but no antilymphangiogenic agent is currently used in clinical practice. Fucoxanthin is a material found in brown algae that holds promise in the context of drug development. Fucoxanthin is a carotenoid with variety of pharmacological functions, including antitumour and anti-inflammatory effects. The ability of fucoxanthin to inhibit lymphangiogenesis remains unclear. The results of experiments performed as part of this study show that fucoxanthin, extracted from Undaria pinnatifida (Wakame), inhibits proliferation, migration and formation of tube-like structures in human LEC (HLEC). In this study, fucoxanthin also suppressed the malignant phenotype in human breast cancer MDA-MB-231 cells and decreased tumour-induced lymphangiogenesis when used in combination with a conditional medium culture system. Fucoxanthin significantly decreased levels of vascular endothelial growth factor (VEGF)-C, VEGF receptor-3, nuclear factor kappa B, phospho-Akt and phospho-PI3K in HLEC. Fucoxanthin also decreased micro-lymphatic vascular density (micro-LVD) in a MDA-MB-231 nude mouse model of breast cancer. These findings suggest that fucoxanthin inhibits tumour-induced lymphangiogenesis in vitro and in vivo, highlighting its potential use as an antilymphangiogenic agent for antitumour metastatic comprehensive therapy in patients with breast cancer.

Aquaporin-3 mediates ovarian steroid hormone-induced motility of endometrial epithelial cells.

STUDY QUESTION: How does aquaporin-3 (AQP3) affect endometrial receptivity? SUMMARY ANSWER: AQP3, which is regulated by the combination and estrogen (E2) and progesterone (P4), induces epithelial-mesenchymal transition (EMT) of endometrial epithelial cells. WHAT IS KNOWN ALREADY: Embryo implantation is an extremely complex process, and endometrial receptivity is essential for successful embryo implantation. Estrogen and progesterone regulate endometrial receptivity. AQP3, which is regulated by estrogen (E2), increases cell migration and invasion ability by regulating the expression of EMT-related factors and influencing the reorganization of the actin cytoskeleton. STUDY DESIGN, SIZE, DURATION: This study investigated the pathophysiological significance of AQP3 in human endometrial function during different phases of the menstrual cycle. PARTICIPANTS/MATERIALS, SETTING, METHODS: AQP3 expression levels during different phases of the menstrual cycle were measured using immunohistochemical assays. In cells of different receptivity (high-receptive RL95-2 cells and low-receptive HEC-1A cells), the expression of AQP3 was measured using western blotting, qRT-PCR and immunofluorescence assays. Activities of AQP3, and its regulation by E2 and P4, were studied through in-vitro experiments using RL95-2 cells. MAIN RESULTS AND THE ROLE OF CHANCE: AQP3 expression in the mid- and late-secretory phases of the human endometrium is significantly higher than in other phases. Since AQP3 expression levels were higher in RL95-2 cells than in HEC-1A cells, mechanisms of AQP3 regulation by E2 and P4 were studied using RL95-2 cells. We provided the first report that P4 up-regulates AQP3 by directly targeting the promoter of the AQP3 gene. The up-regulation of AQP3 expression by a combination of E2 and P4 is significantly higher than that caused by either E2 or P4 alone. Together E2 and P4 promote RL95-2 cell migration and invasion by inducing EMT through AQP3. We also found that AQP3 co-localizes with ezrin and affects the formation of filopodia and lamellipodia during the E2 and P4-induced EMT process but has no effect on the expression of ezrin and F-actin. LARGE SCALE DATA: N/A. LIMITATIONS, REASONS FOR CAUTION: It is still unclear whether AQP3 is a main regulator of endometrial receptivity or one of several factors influencing the process. WIDER IMPLICATIONS OF THE FINDINGS: Further investigation on AQP3 may contribute to a greater understanding of endometrial receptivity. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the National Natural Scientific Grants of China (No. 31570798), the Program for Liaoning Excellent Talents in University (LR2017042), the Doctoral Scientific Research Foundation of Liaoning province (201601236), and the Liaoning Provincial Program for Top Discipline of Basic Medical Sciences. There are no conflicts of interest.

Osteopontin Promotes Bone Destruction in Periapical Periodontitis by Activating the NF-κB Pathway.

BACKGROUND/AIMS: Periapical periodontitis is caused by bacterial infection and results in both one destruction and tooth loss. Osteopontin (OPN) is a secreted phosphorylated glycoprotein that participates in bone metabolism. METHODS: Thirty-three patients with chronic periapical periodontitis and 10 patients who had undergone the orthodontic removal of healthy tooth tissue (control) at the periodontal ligament were investigated, and an animal model of mouse periapical periodontitis was established for an in vivo analysis. The relationship between OPN and bone destruction during periapical periodontitis was analyzed. Osteoblasts and osteoclasts were cultured in vitro and treated with lipopolysaccharide. An inhibitor of NF-κB was used to pretreat the transfected cells. RESULTS: OPN increased osteoclast proliferation and differentiation, but reduced osteoblasts proliferation and differentiation. OPN activated the NF-κB pathway during periapical periodontitis and accelerated the transfer and phosphorylation of P65 from the cytoplasm to the nucleus. CONCLUSION: This study demonstrated that OPN played important roles in the progression of periapical periodontitis, and a dual role in bone metabolism during periapical periodontitis, linking osteoclasts and osteoblasts. The underlying mechanism may be related to the NF-κB pathway.