Efp promotes in vitro and in vivo growth of endometrial cancer cells along with the activation of nuclear factor-κB signaling

Role of the tripartite motif (TRIM) family in female genital neoplasms

The tripartite motif proteins (TRIMs) family represents a class of highly conservative proteins which play a large regulatory role in molecular processes. Recently, increasing evidence has demonstrated a role of TRIMs in female genital neoplasms. Our review thereby aimed to provide an overview of the biological involvement of TRIMs in female genital neoplasms, to provide a better understanding of its role in the development and progression of such diseases, and emphasize its potential as targeted cancer therapy. Overall, our review highlighted that the wide-ranging roles of TRIMs, in not only target protein ubiquitination, tumor migration and/or invasion, epithelial-mesenchymal transition, stemness, cell adhesion, proliferation, cell cycle regulation, and apoptosis, but also in influencing estrogenic, and chemotherapy response.

The role of TRIM25 in the occurrence and development of cancers and inflammatory diseases

The tripartite motif (TRIM) family proteins are a group of proteins involved in different signaling pathways. The changes in the expression regulation, function, and signaling of this protein family are associated with the occurrence and progression of a wide range of disorders. Given the importance of these proteins in pathogenesis, they can be considered as potential therapeutic targets for many diseases. TRIM25, as an E3-ubiquitin ligase, is involved in the development of various diseases and cellular mechanisms, including antiviral innate immunity and cell proliferation. The clinical studies conducted on restricting the function of this protein have reached promising results that can be further evaluated in the future. Here, we review the regulation of TRIM25 and its function in different diseases and signaling pathways, especially the retinoic acid-inducible gene-I (RIG-I) signaling which prompts many kinds of cancers and inflammatory disorders.

TRIM25 participates in the fibrous tissue hyperplasia induced by ALV-J infection in chickens by targeting 14-3-3σ protein

ALV-J-SD1005 strain was subcutaneously inoculated into the necks of 1-day-old HY-Line Brown chickens and caused severe growth retardation, viremia and subcutaneous fibrosarcomas in the necks of all infected chickens from 14 days post inoculation (DPI) to 21 DPI, and also significantly increased the expressions of TRIM25, P53, etc., but significantly decreased the expressions of 14-3-3σ, etc. Overexpression of chicken TRIM25 (chTRIM25) significantly promoted cell proliferation and improved the expressions of P53, CDC2, and CDK2 tumor factors; and significantly inhibited the expression of 14-3-3σ in ALV-J-SD1005-infected DF1 cells; but knockdown of chTRIM25 caused the opposite effects. The results of co-immunoprecipitation (Co-IP) and confocal microscopy confirmed that chTRIM25 can recognize and bind 14-3-3σ protein in ALV-J-SD1005-infected cells, and they were co-located in the cytoplasm. It can be concluded that chTRIM25 participates in the fibrous tissue hyperplasia induced by ALV-J-SD1005 infections in chickens by binding 14-3-3σ protein and regulating the expressions of 14-3-3σ, P53, CDC2, and CDK2.

Identification of peptide binding sequence of TRIM25 on 14-3-3σ by bioinformatics and biophysical techniques

14-3-3σ protein is one of the seven isoforms from the highly conserved eukaryotic 14-3-3 protein family. Downregulation of 14-3-3σ expression has been observed in various tumors. TRIM25 is responsible for the proteolytic degradation of 14-3-3σ, in which abrogation of TRIM25 suppressed tumor growth through 14-3-3σ upregulation. However, to date, the exact 14-3-3σ interacting residues of TRIM25 have yet to be resolved. Thus, this study attempts to identify the peptide binding sequence of TRIM25 on 14-3-3σ via both bioinformatics and biophysical techniques. Multiple sequence alignment of the CC domain of TRIM25 revealed five potential peptide binding sequences (Peptide 1-5). Nuclear magnetic resonance (NMR) assay (1H CPMG) identified Peptide 1 as an important sequence for binding to 14-3-3σ. Competition NMR assay suggested that Peptide 1 binds to the amphipathic pocket of 14-3-3σ with an estimated KD of 116.4 µM by isothermal titration calorimetry. Further in silico docking and molecular dynamics simulations studies proposed that Peptide 1 is likely to interact with Lys49, Arg56, Arg129, and Tyr130 residues at the amphipathic pocket of 14-3-3σ. These results suggest that Peptide 1 may serve as a biological probe or a template to design inhibitors of TRIM25-14-3-3σ interaction as a potentially novel class of anticancer agents.Communicated by Ramaswamy H. Sarma.

The interplay of sex steroid hormones and microRNAs in endometrial cancer: current understanding and future directions

Introduction

Endometrial cancer is a hormone-dependent malignancy, and sex steroid hormones play a crucial role in its pathogenesis. Recent studies have demonstrated that microRNAs (miRNAs) can regulate the expression of sex steroid hormone receptors and modulate hormone signaling pathways. Our aim is to provide an overview of the current understanding of the role of miRNAs in endometrial cancer regulated by sex steroid hormone pathways.

Methods

A thorough literature search was carried out in the PubMed database. The articles published from 2018 to the present were included. Keywords related to miRNAs, endometrial cancer, and sex steroid hormones were used in the search.

Results

Dysregulation of miRNAs has been linked to abnormal sex steroid hormone signaling and the development of endometrial cancer. Various miRNAs have been identified as modulators of estrogen and progesterone receptor expression, and the miRNA expression profile has been shown to be a predictor of response to hormone therapy. Additionally, specific miRNAs have been implicated in the regulation of genes involved in hormone-related signaling pathways, such as the PI3K/Akt/mTOR and MAPK/ERK pathways.

Conclusion

The regulation of sex steroid hormones by miRNAs is a promising area of research in endometrial cancer. Future studies should focus on elucidating the functional roles of specific miRNAs in sex steroid hormone signaling and identifying novel miRNA targets for hormone therapy in endometrial cancer management.

Testis-expressed gene 11 inhibits cisplatin-induced DNA damage and contributes to chemoresistance in testicular germ cell tumor

Testicular germ cell tumor (TGCT) is a rare cancer but the most common tumor among adolescent and young adult males. Patients with advanced TGCT often exhibit a worse prognosis due to the acquisition of therapeutic resistance. Cisplatin-based chemotherapy is a standard treatment for advanced TGCTs initially sensitive to cisplatin, as exemplified by embryonal carcinoma. The acquisition of cisplatin resistance, however, could be a fatal obstacle for TGCT management. To identify cisplatin resistance-related genes, we performed transcriptome analysis for cisplatin-resistant TGCT cells compared to parental cells. In two types of cisplatin-resistant TGCT cell models that we established from patient-derived TGCT cells, and from the NEC8 cell line, we found that mRNA levels of the high-mobility-group nucleosome-binding gene HMGN5 and meiosis-related gene TEX11 were remarkably upregulated compared to those in the corresponding parental cells. We showed that either HMGN5 or TEX11 knockdown substantially reduced the viability of cisplatin-resistant TGCT cells in the presence of cisplatin. Notably, TEX11 silencing in cisplatin-resistant TGCT cells increased the level of cleaved PARP1 protein, and the percentage of double-strand break marker γH2AX-positive cells. We further demonstrated the therapeutic efficiency of TEX11-specific siRNA on in vivo xenograft models derived from cisplatin-resistant patient-derived TGCT cells. Taken together, the present study provides a potential insight into a mechanism of cisplatin resistance via TEX11-dependent pathways that inhibit apoptosis and DNA damage. We expect that our findings can be applied to the improvement of cisplatin-based chemotherapy for TGCT, particularly for TEX11-overexpressing tumor.

The E3 Ligases in Cervical Cancer and Endometrial Cancer

Endometrial (EC) and cervical (CC) cancers are the most prevalent malignancies of the female reproductive system. There is a global trend towards increasing incidence and mortality, with a decreasing age trend. E3 ligases label substrates with ubiquitin to regulate their activity and stability and are involved in various cellular functions. Studies have confirmed abnormal expression or mutations of E3 ligases in EC and CC, indicating their vital roles in the occurrence and progression of EC and CC. This paper provides an overview of the E3 ligases implicated in EC and CC and discusses their underlying mechanism. In addition, this review provides research advances in the target of ubiquitination processes in EC and CC.

Elucidation of TRIM25 ubiquitination targets involved in diverse cellular and antiviral processes

The tripartite motif (TRIM) family of E3 ubiquitin ligases is well known for its roles in antiviral restriction and innate immunity regulation, in addition to many other cellular pathways. In particular, TRIM25-mediated ubiquitination affects both carcinogenesis and antiviral response. While individual substrates have been identified for TRIM25, it remains unclear how it regulates diverse processes. Here we characterized a mutation, R54P, critical for TRIM25 catalytic activity, which we successfully utilized to "trap" substrates. We demonstrated that TRIM25 targets proteins implicated in stress granule formation (G3BP1/2), nonsense-mediated mRNA decay (UPF1), nucleoside synthesis (NME1), and mRNA translation and stability (PABPC4). The R54P mutation abolishes TRIM25 inhibition of alphaviruses independently of the host interferon response, suggesting that this antiviral effect is a direct consequence of ubiquitination. Consistent with that, we observed diminished antiviral activity upon knockdown of several TRIM25-R54P specific interactors including NME1 and PABPC4. Our findings highlight that multiple substrates mediate the cellular and antiviral activities of TRIM25, illustrating the multi-faceted role of this ubiquitination network in modulating diverse biological processes.

Efp/TRIM25 and Its Related Protein, TRIM47, in Hormone-Dependent Cancers

Increasing attention has been paid to the biological roles of tripartite motif-containing (TRIM) family proteins, which typically function as E3 ubiquitin ligases. Estrogen-responsive finger protein (Efp), a member of the TRIM family proteins, also known as TRIM25, was originally identified as a protein induced by estrogen and plays critical roles in promoting endocrine-related cancers, including breast cancer, endometrial cancer, and prostate cancer. The pathophysiological importance of Efp made us interested in the roles of other TRIM family proteins that share a similar structure with Efp. Based on a phylogenetic analysis of the C-terminal region of TRIM family proteins, we focused on TRIM47 as a protein belonging to the same branch as Efp. TRIM47 is a poor prognostic factor in both breast cancer and prostate cancer. Atypical lysine-27-like poly-ubiquitination was involved in the underlying mechanism causing endocrine resistance in breast cancer. We also discuss the functions of Efp and TRIM47 in other types of cancers and innate immunity by introducing substrates the are modified by poly-ubiquitination.

Long Intergenic Noncoding RNA OIN1 Promotes Ovarian Cancer Growth by Modulating Apoptosis-Related Gene Expression

Patients with advanced ovarian cancer usually exhibit high mortality rates, thus more efficient therapeutic strategies are expected to be developed. Recent transcriptomic studies revealed that long intergenic noncoding RNAs (lincRNAs) can be a new class of molecular targets for cancer management, because lincRNAs likely exert tissue-specific activities compared with protein-coding genes or other noncoding RNAs. We here show that an unannotated lincRNA originated from chromosome 10q21 and designated as ovarian cancer long intergenic noncoding RNA 1 (OIN1), is often overexpressed in ovarian cancer tissues compared with normal ovaries as analyzed by RNA sequencing. OIN1 silencing by specific siRNAs significantly exerted proliferation inhibition and enhanced apoptosis in ovarian cancer cells. Notably, RNA sequencing showed that OIN1 expression was negatively correlated with the expression of apoptosis-related genes ras association domain family member 5 (RASSF5) and adenosine A1 receptor (ADORA1), which were upregulated by OIN1 knockdown in ovarian cancer cells. OIN1-specifc siRNA injection was effective to suppress in vivo tumor growth of ovarian cancer cells inoculated in immunodeficient mice. Taken together, OIN1 could function as a tumor-promoting lincRNA in ovarian cancer through modulating apoptosis and will be a potential molecular target for ovarian cancer management.

TRIM25: A central factor in breast cancer

TRIM25 is emerging as a central factor in breast cancer due to its regulation and function. In particular, it has been shown that: (1) Estrogens modulate TRIM25 gene expression; (2) TRIM25 has activity as an E3-ligase enzyme for ubiquitin; and (3) TRIM25 is also an E3 ligase for interferon-stimulated gene 15 protein in the ISGylation system. Consequently, the proteome of mammary tissue is affected by TRIM25-associated pathways, involved in tumor development and metastasis. Here, we discuss the findings on the mechanisms involved in regulating TRIM25 expression and its functional relevance in breast cancer progression. These studies suggest that TRIM25 may be a biomarker and a therapeutic target for breast cancer.

Group size, partner choice and collaborative actions in male Indo-Pacific bottlenose dolphins (Tursiops aduncus)

Due to the diversity of the phenomenon, dolphin cooperation has attracted considerable research interest in both wild populations and those under human care. Dolphins cooperate in various contexts, including group hunting, alloparental care, social learning, social play and alliance formation for securing mates. This investigation focused on the effect of group size and partner choice in a cooperative task using systematic group testing. A cooperative enrichment device was made of a PVC tube containing fish and ice that was temporarily sealed with two PVC caps with rope handles attached. The device was designed to be operated by pairs of dolphins, opened by simultaneous pull of its two handles. The analysis focused on two behaviours, cooperative opening and cooperative play with the device. Testing focused on an adult male dolphin group including four to six individuals and using a single or two devices. Altogether five group testing arrangements and a pairwise testing phase were conducted. Out of the six dolphins, five showed active involvement. All ten possible pairs of the five active dolphins were successful in opening and playing with the device cooperatively. Cooperation increased with group size, but the social networks showed no significant differences among group arrangements. However, the cooperative pairs showed a significant difference in success rate during pairwise vs group testing, while demonstrating a strong partner preference. This study provides the first evidence for partner choice with regards to cooperation in male dolphins.

TRIMming Down Hormone-Driven Cancers: The Biological Impact of TRIM Proteins on Tumor Development, Progression and Prognostication

The tripartite motif (TRIM) protein family is attracting increasing interest in oncology. As a protein family based on structure rather than function, a plethora of biological activities are described for TRIM proteins, which are implicated in multiple diseases including cancer. With hormone-driven cancers being among the leading causes of cancer-related death, TRIM proteins have been described to portrait tumor suppressive or oncogenic activities in these tumor types. This review describes the biological impact of TRIM proteins in relation to hormone receptor biology, as well as hormone-independent mechanisms that contribute to tumor cell biology in prostate, breast, ovarian and endometrial cancer. Furthermore, we point out common functions of TRIM proteins throughout the group of hormone-driven cancers. An improved understanding of the biological impact of TRIM proteins in cancer may pave the way for improved prognostication and novel therapeutics, ultimately improving cancer care for patients with hormone-driven cancers.

Transcriptomic analysis of hormone-sensitive patient-derived endometrial cancer spheroid culture defines Efp as a proliferation modulator

Estrogen-responsive endometrial cancer (EC) is prevalent in uterine cancer. Its precise molecular mechanisms remain to be elucidated partly because of limited availability of estrogen-sensitive EC models recapitulating clinical pathophysiology. We previously established EC patient-derived cancer cell (EC-PDC) spheroid culture with high expression of estrogen receptor α (ERα). Using this EC-PDC, we study the transcriptional regulation and function of estrogen-responsive finger protein (Efp), a prototypic tripartite motif (TRIM) protein that modulates protein degradation and RNA processing. Intense estrogen-dependent EFP mRNA induction and high ERα occupancy to EFP estrogen responsive element (ERE) were observed in EC-PDC. Luciferase reporter gene assay showed that the ERE facilitates EFP transcriptional activity estrogen-dependently. siRNA-mediated Efp silencing in EC-PDC resulted in suppressed spheroid proliferation and altered gene expression profile, featuring downregulation of genes related to cell cycle (e.g., CDK6) and inflammation/immune responses (e.g., IL10RA, IL26, and IL6ST) while unaffected expression of cancer stemness-related markers. Taken together, EC-PDC spheroid culture is a powerful EC tool that enables to dissect Efp-mediated ERα signaling pathways as an estrogen-sensitive EC model. This study provides an insight into alternative EC therapeutic strategies targeting ERα-Efp axis.

Regulation of p53 by E3s

More than 40 years of research on p53 have given us tremendous knowledge about this protein. Today we know that p53 plays a role in different biological processes such as proliferation, invasion, pluripotency, metabolism, cell cycle control, ROS (reactive oxygen species) production, apoptosis, inflammation and autophagy. In the nucleus, p53 functions as a bona-fide transcription factor which activates and represses transcription of a number of target genes. In the cytoplasm, p53 can interact with proteins of the apoptotic machinery and by this also induces cell death. Despite being so important for the fate of the cell, expression levels of p53 are kept low in unstressed cells and the protein is largely inactive. The reason for the low expression level is that p53 is efficiently degraded by the ubiquitin-proteasome system and the vast inactivity of the tumor suppressor protein under normal growth conditions is due to the absence of activating and the presence of inactivating posttranslational modifications. E3s are important enzymes for these processes as they decorate p53 with ubiquitin and small ubiquitin-like proteins and by this control p53 degradation, stability and its subcellular localization. In this review, we provide an overview about E3s that target p53 and discuss the connection between p53, E3s and tumorigenesis.

RNA-binding protein NONO promotes breast cancer proliferation by post-transcriptional regulation of SKP2 and E2F8

The majority of breast cancers are primarily hormone‐sensitive and can be managed by endocrine therapy, although therapy‐resistant or hormone‐refractory cancers need alternative treatments. Recently, increasing attention is being paid to RNA‐binding proteins (RBP) in cancer pathophysiology. The precise role of RBP in breast cancer, however, remains to be clarified. We herein show that an RBP non‐POU domain‐containing octamer binding (NONO) plays a critical role in the pathophysiology of breast cancers regardless of their hormone dependency. Clinicopathological and immunohistochemical study of 127 breast cancer cases showed that NONO is a significant independent prognostic factor for breast cancer patients. Notably, siRNA‐mediated NONO knockdown substantially repressed the proliferation of both hormone‐sensitive MCF‐7 and hormone‐refractory MB‐MDA‐231 breast cancer cells. Integrative analysis combined with expression microarray and RIP‐sequencing (RNA immunoprecipitation‐sequencing) showed that NONO post‐transcriptionally regulates the expression of cell proliferation‐related genes by binding to their mRNAs, as exemplified by S‐phase‐associated kinase 2 and E2F transcription factor 8. Overall, these results suggest that NONO is a key regulator for breast cancer proliferation through the pre‐mRNA splicing of cell proliferation‐related genes and could be a potential new diagnostic and therapeutic target for advanced disease.