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

Review the progression of ovarian clear cell carcinoma from the perspective of genomics and epigenomics

Ovarian clear cell carcinoma (OCCC) is a rare subtype of epithelial ovarian cancer with unique molecular characteristics, specific biological and clinical behavior, poor prognosis and high resistance to chemotherapy. Pushed by the development of genome-wide technologies, our knowledge about the molecular features of OCCC has been considerably advanced. Numerous studies are emerging as groundbreaking, and many of them are promising treatment strategies. In this article, we reviewed studies about the genomics and epigenetics of OCCC, including gene mutation, copy number variations, DNA methylation and histone modifications.

Pathobiological functions and clinical implications of annexin dysregulation in human cancers

Annexins are an extensive superfamily of structurally related calcium- and phospholipid-binding proteins, largely conserved and widely distributed among species. Twelve human annexins have been identified, referred to as Annexin A1-13 (A12 remains as of yet unassigned), whose genes are spread throughout the genome on eight different chromosomes. According to their distinct tissue distribution and subcellular localization, annexins have been functionally implicated in a variety of biological processes relevant to both physiological and pathological conditions. Dysregulation of annexin expression patterns and functions has been revealed as a common feature in multiple cancers, thereby emerging as potential biomarkers and molecular targets for clinical application. Nevertheless, translation of this knowledge to the clinic requires in-depth functional and mechanistic characterization of dysregulated annexins for each individual cancer type, since each protein exhibits varying expression levels and phenotypic specificity depending on the tumor types. This review specifically and thoroughly examines the current knowledge on annexin dysfunctions in carcinogenesis. Hence, available data on expression levels, mechanism of action and pathophysiological effects of Annexin A1-13 among different cancers will be dissected, also further discussing future perspectives for potential applications as biomarkers for early diagnosis, prognosis and molecular-targeted therapies. Special attention is devoted to head and neck cancers (HNC), a complex and heterogeneous group of aggressive malignancies, often lately diagnosed, with high mortality, and scarce therapeutic options.

Green Tea Epigallocatechin-3-Gallate Regulates Autophagy in Male and Female Reproductive Cancer

With a rich abundance of natural polyphenols, green tea has become one of the most popular and healthiest nonalcoholic beverages being consumed worldwide. Epigallocatechin-3-gallate (EGCG) is the predominant catechin found in green tea, which has been shown to promote numerous health benefits, including metabolic regulation, antioxidant, anti-inflammatory, and anticancer. Clinical studies have also shown the inhibitory effects of EGCG on cancers of the male and female reproductive system, including ovarian, cervical, endometrial, breast, testicular, and prostate cancers. Autophagy is a natural, self-degradation process that serves important functions in both tumor suppression and tumor cell survival. Naturally derived products have the potential to be an effective and safe alternative in balancing autophagy and maintaining homeostasis during tumor development. Although EGCG has been shown to play a critical role in the suppression of multiple cancers, its role as autophagy modulator in cancers of the male and female reproductive system remains to be fully discussed. Herein, we aim to provide an overview of the current knowledge of EGCG in targeting autophagy and its related signaling mechanism in reproductive cancers. Effects of EGCG on regulating autophagy toward reproductive cancers as a single therapy or cotreatment with other chemotherapies will be reviewed and compared. Additionally, the underlying mechanisms and crosstalk of EGCG between autophagy and other cellular processes, such as reactive oxidative stress, ER stress, angiogenesis, and apoptosis, will be summarized. The present review will help to shed light on the significance of green tea as a potential therapeutic treatment for reproductive cancers through regulating autophagy.

Membrane-cytoplasm translocation of annexin A4 is involved in the metastasis of colorectal carcinoma

Annexin A4 (ANXA4) is a Ca²⁺- and phospholipid-binding protein that belongs to the annexin family, which is involved in the development of multiple tumour types via NF-κB signalling. In this study, we verified the high expression and membrane-cytoplasm translocation of ANXA4 in colorectal carcinoma (CRC). Calcium/calmodulin-dependent protein kinase II gamma (CAMK2γ) was found to be important for high ANXA4 expression in CRC, whereas carbonic anhydrase (CA1) promoted ANXA4 aggregation in the cell membrane. An increased Ca²⁺ concentration attenuated the small ubiquitin-like modifier (SUMO) modification of cytoplasmic ANXA4 and ANXA4 stabilization, and relatively high expression of ANXA4 promoted CRC tumorigenesis and epithelial-mesenchymal transition (EMT).

p53 and ANXA4/NF‑κB p50 complexes regulate cell proliferation, apoptosis and tumor progression in ovarian clear cell carcinoma

Annexin IV (ANXA4) is highly expressed in ovarian clear cell carcinoma (OCCC); however, its underlying molecular mechanism in OCCC remains unknown. The present study aimed to identify the molecule that ANXA4 may act on and to determine its underlying molecular mechanism. Immunohistochemistry, co‑immunoprecipitation and western blotting were performed to detect the expression and interaction of ANXA4, and its associated proteins. Furthermore, MTT assay, flow cytometry, western blotting and gene expression profile enrichment analysis were performed to identify the potential role and molecular mechanism of ANXA4 in OCCC. The results demonstrated that ANXA4 and nuclear factor‑κ‑light‑chain‑enhancer of activated B cells (NF‑κB) p50 nuclear expression levels were significantly higher in OCCC tissues compared with other subtypes of ovarian cancer, such as serous and mucinous. In addition, a significantly positive correlation was observed between ANXA4 and NF‑κB p50 expression in OCCC; however, the expression levels of mutant p53 and ANXA4 were negatively correlated in a linear manner. These results suggest that ANXA4 and NF‑κB p50 may be potential independent risk factors for poor prognosis. ANXA4 and NF‑κB p50 were demonstrated to interact and their expression was co‑localized. The cBioPortal database was used to construct a protein‑protein interaction network between ANXA4, NF‑κB p50 and p53, and functional pathway analysis indicated that the genes were predominantly enriched in the cell cycle and during apoptosis. Transfection of the ANXA4 gene increased the expression of NF‑κB p50, as well as its downstream targets, Cyclin D1 and B‑cell lymphoma‑2 (Bcl‑2). Furthermore, transfection of the ANXA4 gene increased proliferation and decreased apoptosis of OCCC cells. Treatment with the NF‑κB inhibitor, BAY 11‑7082, decreased Cyclin D1 and Bcl‑2 expression levels. Collectively, the results of the present study suggest that wild p53 activates ANXA4 transcription, promotes its expression and enhances NF‑κB p50 and ANXA4 interaction. This in turn activates the NF‑κB signaling pathway, promotes cell cycle progression and inhibits apoptosis, thus contributing to the malignant progression of OCCC. Thus, ANXA4 and NF‑κB p50 may be used as prognostic biomarkers, and may be molecular therapeutic targets in OCCC.

Annexin A8 can serve as potential prognostic biomarker and therapeutic target for ovarian cancer: based on the comprehensive analysis of Annexins

BACKGROUND

Annexins are involved in vesicle trafficking, cell proliferation and apoptosis, but their functional mechanisms in ovarian cancer remain unclear. In this study, we analyzed Annexins in ovarian cancer using different databases and selected Annexin A8 (ANXA8), which showed the greatest prognostic value, for subsequent validation in immunohistochemical (IHC) assays.

METHODS

The mRNA expression levels, genetic variations, prognostic values and gene-gene interaction network of Annexins in ovarian cancer were analyzed using the Oncomine, Gene Expression Profiling Interactive Analysis (GEPIA), cBioPortal, Kaplan-Meier plotter and GeneMANIA database. ANXA8 was selected for analyzing the biological functions and pathways of its co-expressed genes, and its correlation with immune system responses via the Database for Annotation, Visualization, and Integrated Discovery (DAVID) and the TISIDB database, respectively. We validated the expression of ANXA8 in ovarian cancer via IHC assays and analyzed its correlation with clinicopathological parameters and prognosis.

RESULTS

ANXA2/3/8/11 mRNA expression levels were significantly upregulated in ovarian cancer, and ANXA5/6/7 mRNA expression levels were significantly downregulated. Prognostic analysis suggested that significant correlations occurred between ANXA2/4/8/9 mRNA upregulation and poor overall survival, and between ANXA8/9/11 mRNA upregulation and poor progression-free survival in patients with ovarian serous tumors. Taken together, results suggested that ANXA8 was most closely associated with ovarian cancer tumorigenesis and progression. Further analyses indicated that ANXA8 may be involved in cell migration, cell adhesion, and vasculature development, as well as in the regulation of PI3K-Akt, focal adhesion, and proteoglycans. Additionally, ANXA8 expression was significantly correlated with lymphocytes and immunomodulators. The IHC results showed that ANXA8 expression was higher in the malignant tumor group than in the borderline and benign tumor groups and normal ovary group, and high ANXA8 expression was an independent risk factor for survival and prognosis of ovarian cancer patients (P = 0.013).

CONCLUSIONS

Members of the Annexin family display varying degrees of abnormal expressions in ovarian cancer. ANXA8 was significantly highly expressed in ovarian cancer, and high ANXA8 expression was significantly correlated with poor prognosis. Therefore, ANXA8 is a high candidate as a novel biomarker and therapeutic target for ovarian cancer.

Ascites from Ovarian Cancer Induces Novel Fucosylated Proteins

Ovarian cancer is considered to be the most lethal type of gynecological cancer. During the advanced stages of ovarian cancer, an accumulation of ascites is observed. Fucosylation has been classified as an abnormal post-translational modification that is present in many diseases, including ovarian cancer. Ovarian cancer cells that are cultured with ascites stimulation change their morphology; concomitantly, the fucosylation process is altered. However, it is not known which fucosylated proteins are modified. The goal of this work was to identify the differentially fucosylated proteins that are expressed by ovarian cancer cell lines that are cultured with ovarian cancer patients' ascites. Aleuria aurantia lectin was used to detect fucosylation, and some changes were observed, especially in the cell membrane. Affinity chromatography and mass spectrometry (MALDI-TOF) were used to identify 6 fucosylated proteins. Four proteins (Intermediate filament family orphan 1 [IFFO1], PHD finger protein 20-like protein 1 [PHF20L1], immunoglobulin gamma 1 heavy chain variable region partial [IGHV1-2], and Zinc finger protein 224 [ZNF224]) were obtained from cell cultures stimulated with ascites, and the other two proteins (Peregrin [BRPF1] and Dystrobrevin alpha [DTNA]) were obtained under normal culture conditions. The fucosylated state of some of these proteins was further analyzed. The experimental results show that the ascites of ovarian cancer patients modulated the fucosylation process. The PHD finger protein 20-like protein 1, Zinc finger protein 224 and Peregrin proteins colocalize with fucosylation at different levels.

Targeting tumor-associated carbohydrate antigens: a phase I study of a carbohydrate mimetic-peptide vaccine in stage IV breast cancer subjects

Tumor-associated carbohydrate antigens (TACAs) support cell survival that could be interrupted by anti-TACA antibodies. Among TACAs that mediate cell survival signals are the neolactoseries antigen Lewis Y (LeY) and the ganglioside GD2. To induce sustained immunity against both LeY and GD2, we developed a carbohydrate mimicking peptide (CMP) as a surrogate pan-immunogen that mimics both. This CMP, referred to as P10s, is the N-terminal half of a peptide vaccine named P10s-PADRE, the C-terminal half of which (PADRE) is a Pan-T-cell epitope. A Phase I dose-escalation trial of P10s-PADRE plus adjuvant MONTANIDE™ ISA 51 VG was conducted in subjects with metastatic breast cancer to test 300 and 500 μg/injection in two cohorts of 3 subjects each. Doses of the P10s-PADRE vaccine were administered to research participants subcutaneously on weeks 1, 2, 3, 7 and 19. Antibody responses to P10s, GD2, and LeY were measured by ELISA. The P10s-PADRE vaccine induced antibodies specifically reactive with P10s, LeY and GD2 in all 6 subjects. Serum antibodies displayed Caspase-3-dependent apoptotic functionality against LeY or GD2 expressing breast cancer cell lines. Immunization with the P10s-PADRE vaccine was well-tolerated and induced functional antibodies, and the data suggest potential clinical benefit.

The transcription factor Ikaros inhibits cell proliferation by downregulating ANXA4 expression in hepatocellular carcinoma

The occurrence and progression of hepatocellular carcinoma (HCC) are affected by complicated signal transduction factors. Our previous study identified Ikaros as a novel reactivated therapeutic target that acts as a transcriptional repressor and reactivates anticancer mechanisms in HCC therapy. Annexin A4 (ANXA4) is a member of the Annexin family that plays an essential role in several cancers, but it has not been investigated in HCC proliferation. Using cDNA microarrays, ANXA4 was shown to be associated with Ikaros in Ikaros-overexpressing cells. The aim of this work was to characterize the relationship between Ikaros and ANXA4 and the role of ANXA4 in HCC. The effect of Ikaros on ANXA4 was analyzed in HCC cell lines and HCC patient samples, and functional recovery experiments were performed between Ikaros and ANXA4. Furthermore, the effect of ANXA4 on cell proliferation in vitro was analyzed by MTT and colony formation assays in HCC cells. We used a subcutaneous xenograft model to elucidate the role of ANXA4 in vivo. We found that ANXA4 overexpression promotes HCC cell proliferation, but Ikaros can inhibit ANXA4 expression by repressing its promoter activity. Moreover, we demonstrated that downregulated expression of ANXA4 inhibited HCC cell proliferation and tumorigenesis in vitro and in vivo. Our findings indicate that ANXA4 may be a critical factor in HCC tumorigenesis. Ikaros is an attractive inhibitor of ANXA4 and may function as an anticancer agent in HCC.