RNF144B-mediated p21 degradation regulated by HDAC3 contribute to enhancing ovarian cancer growth and metastasis.

We have shown before that HDAC3 was involved in the pathogenesis of ovarian cancer; however, the specific mechanism of HDAC3 on the pathogenesis of ovarian cancer has not been thoroughly studied. To explore the related proteins in the mechanism of HDAC3 on ovarian cancer. The transcriptome profiles were identified in ovarian carcinoma cells with HDAC3 knockdown or overexpression. Reverse transcription-quantitative polymerase chain reaction (RT-qPCR) and western blot analysis were used to verify transfection efficiency. Immunofluorescence staining were performed to detect the expression levels of HDAC3 and RNF144B in tissues. Cell proliferation, apoptosis, migration and invasion were confirmed by cell counting Kit-8 (CCK-8), terminal deoxynucleotidyl transferase (TUNEL) and transwell assay, respectively. The protein expression of p53, p21, Bax and Bcl-2 was confirmed by western blot, and CoIP assay was used to validate RNF144B/P21/P53 interaction. Meanwhile, the protein synthesis inhibitor cycloheximide (CHX) was performed to treat cells to probe p21 stability. Finally, we established an in vivo tumor model to explore the effects of HDAC3 and RNF144B on tumor growth. Microarray results showed that among the overlapping genes in the two profiles (HDAC3 knockdown and overexpression), RNF144B was decreased or increased in ovarian carcinoma cells with HDAC3 knockdown or overexpression, HDAC3 overexpression promoted RNF144B expression, and HDAC3 knockdown hindered RNF144B levels. The levels of HDAC3 and RNF144B in malignant ovarian cancer were significantly higher than those in normal ovarian tissue and benign ovarian cancer tissue. RNF144B promoted cell proliferation, migration and invasion, and inhibited cell apoptosis. In addition, overexpression of HDAC3 or RNF144B inhibited p53/p21/Bax expression and promoted Bcl-2 expression. Knockout of HDAC3 or RNF144B has the opposite effect, and RNF144B interacted with p21 and regulated the p21/p53 complex degradation, and finally in vivo experiments proved that HDAC3 and RNF144B promoted tumor growth. RNF144B-mediated p21 degradation regulated by HDAC3 contributed to enhancing ovarian cancer growth and metastasis.

FOXA1 can be modulated by HDAC3 in the progression of epithelial ovarian carcinoma.

FOXA1 is associated with malignant tumors, but the function of FOXA1 in EOC is unclear. HDAC3 can influence the proliferation, migration and invasion ability of EOC. In this study, we wanted to explore the function of FOXA1 in ovarian cancer and the relationship between HDAC3 and FOXA1.The expression of HDAC3 and FOXA1 was detected by immunohistochemical staining of primary lesions from 127 epithelial ovarian carcinoma patients. A proliferation assay, a Transwell assay, an apoptosis assay and animal experiments were used to assess the proliferation, invasion and apoptosis abilities of ovarian cancer cells before and after transfection with FOXA1. The relevance of the in vitro findings was confirmed in xenografts. The H-scores for FOXA1 and HDAC3 staining in FIGO stage III-IV were noticeably higher and predicted adverse clinical outcomes in patients with ovarian cancer. The expression level of HDAC3 was significantly correlated with the expression level of FOXA1. Invasion, proliferation and apoptosis capacity and tumor formation were decreased in the FOXA1-knockdown cells. Experiments in xenografts confirmed that HDAC3 mediated tumor formation. In conclusion, FOXA1 can be modulated by HDAC3 through the Wnt/ß-catenin signaling pathway, and FOXA1 plays essential roles in the proliferation, apoptosis and invasion of EOC cell lines and xenograft experiments.

Human Epididymis Protein 4 and Lewis y Enhance Chemotherapeutic Resistance in Epithelial Ovarian Cancer Through the p38 MAPK Pathway.

INTRODUCTION: Ovarian cancer has a high mortality rate due to difficulties in early detection and chemotherapy resistance. Human epididymal protein 4 (HE4) has been adopted as a novel serum biomarker for early ovarian cancer diagnosis, and the presence of Lewis y antigen modifications on HE4 in ovarian cancer cell lines has been detected in previous studies. The aim of this study was to analyze the expression of HE4 and Lewis y antigen in human ovarian cancer in order to find a correlation between them, as well as with the clinical pathological parameters of patients with ovarian cancer. METHODS: Immunohistochemistry was used to detect the respective expression of these compounds in two patient groups (chemotherapy-resistant and chemotherapy-sensitive) containing a total of 95 patients. Then, a bioinformatic approach was adopted and online large sample databases (TCGA, CCLE, and GTEx; Metascape, Cytoscape) were used to explore the potential mechanisms of action of these compounds. RESULTS: The results of this study demonstrate that high HE4 and Lewis y expression could be used as markers for chemotherapy resistance and poor prognosis in patients with ovarian cancer. These two expression events were widely correlated in various cancer tissues and are thought to act by activating the p38 mitogen-activated protein kinases (MAPK) pathway and inducing Vascular Endothelial Growth Factor A (VEGFA), Prostaglandin-Endoperoxide Synthase 2 (PTGS2), Early Growth Response 1 (EGR1), and Hypoxia-Inducible Factor 1-Alpha (HIFI1A), thereby promoting malignant biological behavior and resistance in ovarian cancer. CONCLUSIONS: These findings not only reveal the possible mechanism by which HE4 and Lewis y antigen affect ovarian cancer but also identify a four-gene signature that could be very useful in ovarian cancer detection and/or the development of new targeted therapies.

A modified suture technique for the treatment of patients with pernicious placenta previa and placenta accreta spectrum: a case series.

BACKGROUND: Pernicious placenta previa complicated by placenta accreta spectrum (PAS) often leads to hysterectomy or even maternal death due to massive bleeding. In recent years, the application of balloons has received increasing attention. It is easier to use and has reasonably good effect. However, for some patients, especially those who still have some placental residue, there might still be active bleeding. To solve this problem, we propose a method of pressure sutures around the balloon to provide a better hemostasis effect. METHODS: An observational study was conducted on patients with pernicious placenta previa and PAS at the Beijing Chaoyang Hospital, Beijing, China, between January 2018 and January 2021. During surgery, an intrauterine balloon was used to compress the hemorrhage site, and two or more absorbable sutures were placed around the uterus to apply strong pressure on the balloon. This method is an updated modification of the Lu-suture which uses a Foley catheter balloon and only one suture. The main improvements include choosing different kinds of balloons depending on various conditions and the addition of a suture below the balloon to provide much stronger pressure and prevent the balloon slipping out through the dilated cervix. RESULTS: A total of 10 women underwent the procedure. The mean estimated intraoperative blood loss was 1,190±548 mL. Post-surgery, the blood loss was less than 200 mL in all patients. The mean blood transfusion [packed red blood cells (pRBC)] required was 2.2±2.6 units. The mean hemostatic time was 8.1±3.4 minutes. CONCLUSIONS: The modified suture technique provided an easy, cheap, and efficient surgical choice for patients with pernicious placenta previa and PAS.

The Relationship between HDAC3 and Malignant Tumors: A Mini Review.

Histone deacetylases 3 (HDAC3) is a member of the histone deacetylases family. This family is associated with cellular physiological function, such as signal transduction, cell cycle, proliferation, apoptosis, and cardiac development. HDAC3 plays an important role in the progression of malignant tumors, especially in terms of proliferation, apoptosis, metastasis, angiogenesis, and anticancer drug resistance. This review discusses the basic elements of HDAC3 and the relationship between HDAC3 and malignant tumors.

HDAC3 positively regulates HE4 expression to promote ovarian carcinoma progression.

OBJECTIVE: To identify the relationship between Histone deacetylase 3 (HDAC3) and Human epididymis protein 4 (HE4) and to explore the mechanisms underlying their effects on the malignant behaviors of ovarian carcinoma cells. METHODS: The expression levels of HDAC3 in ovarian carcinoma tissues were identified by immunohistochemistry, Western blot and real-time PCR. A wound healing assay, a Transwell assay and a CCK8 proliferation assay were used to assess the proliferation, invasion and metastatic capacities of ovarian carcinoma cells before and after transfection and HDAC3 protein treatment. HDAC3 and HE4 protein expression level in epithelial ovarian tissues were detected by immunohistochemistry, and the relationship between them was examined. RESULTS: HE4 was identified as an HDAC3-interacting protein. HDAC3 promotes ovarian carcinoma cell proliferation, invasion and migration by increasing the expression of HE4. HE4 and HDAC3 expression levels were significantly higher in malignant epithelial ovarian tissues than they were in benign and normal epithelial ovarian tissues. HDAC3 gene interference downregulated the expression of the PI3K/AKT signaling pathway-associated molecules P-PI3K/PI3K and P-AKT/AKT. CONCLUSION: HDAC3 expression is higher in ovarian carcinoma and promotes ovarian carcinoma cell proliferation, invasion and migration. HDAC3 and HE4 binding activates the PI3K/AKT signaling pathway, enhances ovarian carcinoma and promotes ovarian carcinoma cell proliferation, invasion and migration. Therefore, inhibiting the relationship between HDAC3 and HE4 may therefore have potential therapeutic value in patients with ovarian carcinoma.

Interaction of HE4 and ANXA2 exists in various malignant cells-HE4-ANXA2-MMP2 protein complex promotes cell migration.

BACKGROUND: The interaction between human epididymis protein 4 (HE4) and annexin A2 (Annexin A2) has been found in ovarian cancer. However, it is dimness whether the interaction exists in other malignant tumors. METHODS: Real-time PCR, western blotting and immunocytochemistry were used to detect mRNA and proteins expression. Co-immunoprecipitation and double-labeling immunofluorescence were used to detect the interaction among HE4, ANXA2 and MMP2. MTS assay was used to test cell proliferation. Adhesion test was used to test cell adhesion. Flow cytometry was applied to examine cell cycle. The scratch test and Transwell assay was performed to detect the migration and invasion of various malignant cell lines. RESULTS: Here we show that the overexpression of HE4 and ANXA2 in various malignant cells is a common phenomenon. HE4 and ANXA2 are co-localized in the cytoplasm and membrane of various tumor cells. ES-2 cells which had both high expression of HE4 and ANXA2 were much stronger in proliferation, adhesion, invasion, and migration than other tumor cells. HE4-ANXA2-MMP2 could form a triple protein complex. HE4 could mediate the expression of MMP2 via ANXA2 to promote cell migration progress. CONCLUSIONS: The interaction of HE4 and ANXA2 exists in various types of cancer cells. HE4 and ANXA2 can promote the proliferation, adhesion, invasion, and migration of cancer cells. HE4-ANXA2-MMP2 form a protein complex and ANXA2 plays the role of "bridge". They performed together to promote cell migration.

Corrigendum to "Expression of HE4 in Endometrial Cancer and Its Clinical Significance".

[This corrects the article DOI: 10.1155/2015/437468.].

High expressions of BCL6 and Lewis y antigen are correlated with high tumor burden and poor prognosis in epithelial ovarian cancer.

Aberrant regulation of BCL6 plays crucial oncogenic roles in various malignant tumors; howbeit, the function of BCL6 in tumorigenesis of ovarian cancer remains unclear. The aim of this study is to investigate the role of BCL6 in ovarian cancer. The methods of immunohistochemical staining, quantitative real-time polymerase chain reaction, immunocytochemical staining, and gene expression profile enrichment analysis were performed to identify the possible role of BCL6 in ovarian cancer. We observed that the expression of BCL6 was significantly higher in ovarian cancer tissues and correlated with higher tumor burden including advanced International Federation of Gynecology and Obstetrics stages, poor differentiation, Type II ovarian cancer, the presence of >1 cm residual tumor size, and appearance of recurrence or death (all p < 0.05). The expression patterns of Lewis y were similar to these of BCL6. Multivariate Cox analysis demonstrated that advanced International Federation of Gynecology and Obstetrics stage, lymph node metastasis, residual tumor size >1 cm, as well as high expressions of BCL6 and Lewis y antigen were independent factors of worse progression-free survival and overall survival (all p < 0.05). There was a positive correlation of the expressions of BCL6 and Lewis y antigen. The associated genes with BCL6 in response to Lewis y antigen were identified, including four upregulated genes ( SOCS3, STAT1, PPARG, and GADD45A) and three downregulated genes ( ACAN, E2F3, and ZBTB7B). In conclusion, the high expressions of BCL6 and Lewis y antigen are associated with development, high tumor burden, and worse prognosis of ovarian cancer and targeting BCL6 could be a novel therapeutic strategy for ovarian cancer treatment.

Annexin A4 fucosylation enhances its interaction with the NF-kB p50 and promotes tumor progression of ovarian clear cell carcinoma.

OBJECTIVE: To study the structural relationship between annexin A4 and the Lewis y antigen and compare their expression and significance in ovarian clear cell carcinoma, and to explore how annexin A4 fucose glycosylation effects the interaction between annexin A4 and NF-kB p50, and how it promotes tumour progression of ovarian clear cell carcinoma. METHODS: Structural relationships between annexin A4 and Lewis y antigen were detected using immunoprecipitation. Annexin A4 and Lewis y antigen expression in various subtypes of ovarian cancer tissues was detected by immunohistochemistry, and the relation between their expression was examined. Any interactions between annexin A4 and NF-kB p50 in ovarian clear cell carcinoma were detected by co-immunoprecipitation. Then looked for changes in expression of Lewis y antigen, annexin A4, NF-kB p50 and a number of downstream related molecules before and after transfection annexin A4 or FUT1, and also analyzed changes in biological processes. RESULTS: Lewis y antigen is a part of annexin A4 structure. The expression rate of both annexin A4 and Lewis y antigen was significantly higher in ovarian clear cell carcinoma than in other subtypes of epithelial ovarian cancer, and are associated with the clinical stages, chemotherapy resistance and poor prognostic. The interaction between annexin A4 and NF-kB p50 promoted cell proliferation, adhesion, invasion, metastasis ability and autophagy, and inhibits apoptosis, Lewis y enhanced this interaction. CONCLUSION: Annexin A4 contains Lewis y structure, Lewis y antigen modification of annexin A4 enhances its interaction with NF-kB p50, which promotes ovarian clear cell carcinoma malignancy progression.

Analysis of the gene expression profile in response to human epididymis protein 4 in epithelial ovarian cancer cells.

Currently, there are emerging multiple studies on human epididymis protein 4 (HE4) in ovarian cancer. HE4 possesses higher sensitivity and specificity than CA125 in the confirmative early diagnosis for ovarian cancer. Although much attention has been given to explore its clinical application, research of the basic mechanisms of HE4 in ovarian cancer are still unclear. In the present study, we provide fundamental data to identify full-scale differentially expressed genes (DEGs) in response to HE4 by use of human whole-genome microarrays in human epithelial ovarian cancer cell line ES-2 following overexpression and silencing of HE4. We found that a total of 717 genes were upregulated and 898 genes were downregulated in the HE4-overexpressing cells vs. the HE4-Mock cells, and 166 genes were upregulated and 285 were downregulated in the HE4-silenced cells vs. the HE4-Mock cells. An overlap of 16 genes consistently upregulated and 8 genes downregulated in response to HE4 were noted. These DEGs were involved in MAPK, steroid biosynthesis, cell cycle, the p53 hypoxia pathway, and focal adhesion pathways. Interaction network analysis predicted that the genes participated in the regulatory connection. Highly differential expression of the FOXA2, SERPIND1, BDKRD1 and IL1A genes was verified by quantitative real-time PCR in 4 cell line samples. Finally, SERPIND1 (HCII) was validated at the protein level by immunohistochemistry in 107 paraffin-embedded ovarian tissues. We found that SERPIND1 may act as a potential oncogene in the development of ovarian cancer. The present study displayed the most fundamental and full-scale data to show DEGs in response to HE4. These identified genes may provide a theoretical basis for investigations of the underlying molecular mechanism of HE4 in ovarian cancer.

Overexpression of HE4 (human epididymis protein 4) enhances proliferation, invasion and metastasis of ovarian cancer.

Overexpression of Human epididymis protein 4 (HE4) related with a role in ovarian cancer tumorigenesis while little is known about the molecular mechanism alteration by HE4 up regulation. Here we reported that overexpressed HE4 promoted ovarian cancer cells proliferation, invasion and metastasis. Furthermore, human whole genome gene expression profile microarrays revealed that 231 differentially expressed genes (DEGs) were altered in response to HE4, in which MAPK signaling, ECM receptor, cell cycle, steroid biosynthesis pathways were involved. The findings suggested that overexpressed HE4 played an important role in ovarian cancer progression and metastasis and that HE4 has the potential to serve as a novel therapeutic target for ovarian cancer.

Expression of HE4 in Endometrial Cancer and Its Clinical Significance.

The main aims of this study were to determine the expression of human epididymis protein 4 (HE4) in endometrial cancer and to explore the relationships between HE4 expression, clinicopathological parameters, and prognosis. Immunohistochemistry was used to detect HE4 expression in 102 cases of endometrial cancer, 30 cases of endometrial atypical hyperplasia, and 20 cases of normal endometrium. The positive expression rate of HE4 in endometrial carcinoma was 84.62%, significantly higher than 66.67% in atypical hyperplasia (P < 0.05) and 15.00% in normal endometrium (P < 0.0.01). With the exception of stage II, HE4 expression in endometrial cancer showed an increasing tendency with increased clinical stage (P < 0.05). The positive expression rate of HE4 increased with a decrease in the degree of differentiation. A statistically significant difference was observed between the highly differentiated group and the poorly differentiated group (P < 0.05). Mortality in endometrial cancer patients with high HE4 expression was significantly higher than that in patients with low HE4 expression (P < 0.05). Endometrial cancer patients with high HE4 expression have a poor prognosis.

Lewis Y antigen modified CD47 is an independent risk factor for poor prognosis and promotes early ovarian cancer metastasis.

CD47 is a membrane receptor that belongs to the immunoglobulin superfamily and plays an important role in the mechanisms of tumor immune escape. CD47 participates in tumor immune escape by combining with SIRPα to reduce the phagocytic activity of macrophages. There are six potential N-glycosylation sites on CD47, and glycosylation is known to be necessary for its membrane localization. However, it is still unknown to what extent glycosylation influences CD47 ligand binding properties and subsequent signaling. By using immunoprecipitation and confocal laser scanning microscopy, we showed that CD47 contains Lewis y antigen. Immunohistochemical analysis demonstrated that both the positive expression and the overexpression of CD47 and Lewis y antigen in cancer tissues and borderline tumors were significantly higher than those in benign ovarian tumors and normal ovarian tissues (P < 0.05). A linear correlation between the expression patterns of CD47 and Lewis y antigen was evident (r = 0.47, P < 0.01). The high expression of CD47 and Lewis y antigen showed significant correlations with the clinical pathological parameters of ovarian cancer [International Federation of Gynecology and Obstetrics (FIGO) standards, lymph node metastasis, and degree of differentiation] (P < 0.05). The Cox model and Kaplan-Meier tests showed that high expression of CD47 was an independent adverse risk factor for the prognosis of ovarian cancer. Cases with both high CD47 and Lewis y antigen expression had poor prognoses. Our study demonstrates that Lewis y antigens of CD47 may play a crucial role in the development of ovarian cancer, and could be new targets for immunotherapy for ovarian cancer.

Expression and clinical significance of annexin A2 and human epididymis protein 4 in endometrial carcinoma.

BACKGROUND: It is well-known that the treatment and monitoring methods are limited for advanced stage of endometrial carcinoma. Biological molecules with expression changes during tumor progression become potential therapeutic targets for advanced stage endometrial carcinoma. Annexin A2 (ANXA2) has been reported to be overexpressed in recurrent endometrial carcinoma, and the expression of human epididymis protein 4 (HE4) is upregulated in endometrial carcinoma. What's more, ANXA2 and HE4 interacted in ovarian cancer and promoted the malignant biological behavior. We speculated that their interaction may exist in endometrial carcinoma as well. We evaluated the expression and the correlation relationship of ANXA2 and HE4 in endometrial carcinoma. METHODS: The expression of ANXA2 and HE4 protein in 84 endometrial carcinoma, 30 endometrial atypical hyperplasia, and 18 normal endometrial tissue samples were then measured using an immunohistochemical assay in paraffin embedded endometrial tissues. The structural relationship between ANXA2 and HE4 was explored by immunoprecipitation and double immunofluorescent staining. RESULTS: ANXA2 and HE4 co-localized in both endometrial tissues and endometrial carcinoma cells. ANXA2 and HE4 were expressed in 95.2 % and 85.7 % of the the endometrial carcinoma, respectively, which were significantly higher than normal endometrium (55.6 % and 16.7 %, both p < 0.05). The expression of ANXA2 and HE4 was significantly correlated with FIGO stage, degree of differentiation, myometrial invasion, and lymph node metastasis. ANXA2 was an independent risk factor for the prognosis of endometrial carcinoma (p < 0.05, hazard ratio [HR] = 8.004). The expression of ANXA2 and HE4 was positively correlated (Spearman correlation coefficient = 0.228, p < 0.05). HE4 was an independent factor for ANXA2 in multivariate linear regression model (p < 0.05). CONCLUSION: We revealed the co-localization of ANXA2 and HE4 in endometrial carcinoma. Expression levels of ANXA2 and HE4 were closely related to the malignant biological behavior of endometrial carcinoma, and ANXA2 was an independent risk factor for poor prognosis. The expression of ANXA2 and HE4 can affect each other.

Membranous expressions of Lewis y and CAM-DR-related markers are independent factors of chemotherapy resistance and poor prognosis in epithelial ovarian cancer.

BACKGROUND: Chemotherapy resistance is a common problem faced by patients diagnosed with epithelial ovarian cancer (EOC). Currently there are no specific or sensitive clinical biomarkers that maybe implemented to identify chemotherapy resistance and give insight to prognosis. The aim of this study is to investigate the roles of Lewis y antigen and the markers associated with cell-adhesion-mediated drug resistance (CAM-DR) in patients with EOC. METHODS: 92 EOC patients who were treated with systemic chemotherapy after cytoreductive surgery were included in this analysis. Patients were divided into two groups, chemotherapy sensitive (n = 56) and resistant (n = 36). Immunohistochemical (IHC) staining for Lewis y and CAM-DR-related cell surface proteins including CD44, CD147, HE4 (Human epididymis protein 4), integrin α5, ß1, αv and ß3 were conducted on tissues collected during primary debulking surgery. Using multivariate logistic regressions, IHC results were compared to clinical variables and chemotherapy resistance to determine possible correlations. The relationships between IHC expression and progression-free survival (PFS) and overall survival (OS) were analyzed using Kaplan-Meier method and Cox regression analysis. RESULTS: Membranous expression of Lewis y and all these CAM-DR-related markers were significantly higher in the resistant group than that of the sensitive group (all P < 0.01). Multivariate regression analysis revealed that high expression of Lewis y, CD44, HE4, integrin α5 and ß1 as well as advanced FIGO stage were independent risk factors for chemotherapy resistance (all P < 0.05). Advanced FIGO stage, lymph node metastasis and high expression of Lewis y, CD44, CD147, HE4, integrin α5, ß1 were associated with a shorter PFS and OS (all P < 0.05). Moreover, multivariate COX analysis demonstrated that the following variates were independent predictors of worse PFS and OS survival: late FIGO stage (P = 0.013, 0.049), high expressions of Lewis y (P = 0.010, 0.036), HE4 (P = 0.006, 0.013) and integrin ß1 (PFS, P = 0.003), integrin α5 (OS, P = 0.019). CONCLUSION: Membranous expression of Lewis y and CAM-DR-related markers including CD44, CD147, HE4, integrin α5, ß1, αv and ß3 are associated with the development of chemotherapy resistance. High expression of Lewis y antigen and CAM-DR-related markers including CD44, CD147, HE4, integrin α5 and ß1 are independent markers for PFS and OS, in which Lewis y and HE4 are the most significant.

The expression of annexin II and Lewis y antigen in ovarian epithelial tumors and the correlation between them.

The main aim of this study was to explore the molecular structural relationship between annexin II (ANXA2) and Lewis y antigen by determining their expression patterns and clinical significance in ovarian epithelial carcinoma. The structural relationship between ANXA2 and Lewis y antigen was examined using immunoprecipitation and confocal laser scanning microscopy in two ovarian caner cell lines ES-2 and CaoV-3. We also constracted the stably transfected cell lines with low ANXA2 gene expression in order to detect the expression level between ANXA2 and Lewis y. ANXA2 and Lewis y were detected in tissues from malignant, borderline, benign, and normal ovarian tissues using immunohistochemical analysis. ANXA2 and Lewis y were present in both two ovarian cancer cells and ANXA2 contained Lewis y antigen. Moreover, expression of Lewis y antigen in ANXA2 from cell after transfection was higher than that before. Our immunohistochemistry data revealed significantly higher positive expression rates of ANXA2 in malignant ovarian tissues, compared to benign tumor and normal tissue, similar to Lewis y antigen levels in ovarian cancer. Notably, tissues displaying marked expression of ANXA2 simultaneously expressed high levels of Lewis y antigen. A linear correlation between the expression patterns of ANXA2 and Lewis y antigen was evident. Consistently, double-labeling immunofluorescence experiments illustrated co-localization of ANXA2 and Lewis y antigen within the same area. In conclusions, ANXA2 contains Lewis y antigen. Our results further demonstrate a close correlation between the expression levels of the two antigens, which are significantly high in ovarian cancer.

Human epididymis protein 4 in association with Annexin II promotes invasion and metastasis of ovarian cancer cells.

BACKGROUND: The objective of the present study was to identify human epididymis protein 4 (HE4) interacting proteins and explore the mechanisms underlying their effect on ovarian cancer cell invasion and metastasis. METHODS: HE4 interacting proteins were identified by mass spectrometry and validated by co-immunoprecipitation and pull-down assays. The scratch test, the Transwell assay and animal experiments were used to assess the invasive and metastatic abilities of ovarian cancer cells before and after transfection and HE4 protein treatment. HE4 and annexin II protein expression in epithelial ovarian tissues was detected by immunohistochemistry, and the relation between their expression levels was examined. RESULTS: Annexin II was identified as an HE4 interacting protein. HE4 and annexin II binding interaction promoted ovarian cancer cell invasion and metastasis. HE4 and annexin II expression levels were significantly higher in malignant epithelial ovarian tissues than in benign and normal epithelial ovarian tissues, and they were higher in tissues with lymph node metastases than in those without. HE4 gene interference downregulated the expression of MAPK and the FOCAL adhesion signaling pathway-associated molecules MKNK2 and LAMB2, and HE4 protein supplementation reversed this effect. CONCLUSION: The binding interaction between HE4 and annexin II activates the MAPK and FOCAL adhesion signaling pathways, promoting ovarian cancer cell invasion and metastasis.

c-Jun transcriptionally regulates alpha 1, 2-fucosyltransferase 1 (FUT1) in ovarian cancer.

Alpha 1, 2-fucosyltransferase (FUT 1/2) is a rate-limiting enzyme that catalyzes the synthesis of Lewis y, a cell membrane-associated carbohydrate antigen. In human ovarian cancer, the upregulated expression of FUT1 and Lewis y is associated with advanced pathological stages and involved in cell proliferation, migration and invasion. However, the mechanism underlying the upregulation of FUT1 is largely unknown. Here, we identify an AP-1 binding site in FUT1 promoter in ovarian cancer cells. c-Jun promotes FUT1 expression, thereby enhancing Lewis y biosynthesis in various ovarian cancer cell lines. Moreover, EMSA, luciferase activity and ChIP assays demonstrate c-Jun directly interacts with FUT1 promoter. Furthermore, FUT1 mediates c-Jun-induced cell proliferation in ovarian cancer cells. In human ovarian cancer samples, c-Jun overexpression is linked to malignant degree and positively correlated to FUT1 and Lewis y expression. Taken together, c-Jun could transcriptionally modulate FUT1 expression in ovarian cancer, implicating the potential application of c-Jun inhibitors for human ovarian cancer therapy.

Overexpression of Lewis y antigen promotes human epididymis protein 4-mediated invasion and metastasis of ovarian cancer cells.

To study Human epididymis protein 4 (HE4) surface fucosylation and to determine the effects and significance of Lewis y antigen on HE4-mediated invasion and metastasis of ovarian cancer cells, we investigated four types of ovarian cancer cells and found that six fucosylated antigens (Lewis y, Lewis x, Lewis a, Lewis b, sLewis a, and sLewis x) were identified on HE4 in ovarian cancer cells. Moreover, modification of the type II sugar chain (Lewis y, Lewis x, and sLewis x) was significantly higher than the type I sugar chain (Lewis a, Lewis b, sLewis a) of the lactose series. To confirm the effects of Lewis y antigen on HE4-mediated invasion and metastasis of ovarian cancer cells, the CaoV-3 cells with high Lewis y antigen on the HE4 surface and ES-2 cells, with high Lewis x antigen but low Lewis y antigen, were investigated. We found that the expression levels of HE4 and Lewis y increased in both cell lines while the level of Lewis x didn't have any change after transfection. Furthermore, the high expression of Lewis y antigen significantly enhanced the HE4-mediated invasion and metastasis of ovarian cancer cells. The invasion and metastasis capacities were significantly decreased after Lewis y antibody blocking. This study demonstrates that overexpression of the Lewis y antigen on HE4 promotes ovarian cancer cell invasion and metastasis, which is likely to be used as a target for the clinical treatment of ovarian cancer.