The tumor suppressor annexin A10 is a novel component of nuclear paraspeckles

RNA-binding is an ancient trait of the Annexin family

Introduction: The regulation of intracellular functions in mammalian cells involves close coordination of cellular processes. During recent years it has become evident that the sorting, trafficking and distribution of transport vesicles and mRNA granules/complexes are closely coordinated to ensure effective simultaneous handling of all components required for a specific function, thereby minimizing the use of cellular energy. Identification of proteins acting at the crossroads of such coordinated transport events will ultimately provide mechanistic details of the processes. Annexins are multifunctional proteins involved in a variety of cellular processes associated with Ca²⁺-regulation and lipid binding, linked to the operation of both the endocytic and exocytic pathways. Furthermore, certain Annexins have been implicated in the regulation of mRNA transport and translation. Since Annexin A2 binds specific mRNAs via its core structure and is also present in mRNP complexes, we speculated whether direct association with RNA could be a common property of the mammalian Annexin family sharing a highly similar core structure. Methods and results: Therefore, we performed spot blot and UV-crosslinking experiments to assess the mRNA binding abilities of the different Annexins, using annexin A2 and c-myc 3'UTRs as well as c-myc 5'UTR as baits. We supplemented the data with immunoblot detection of selected Annexins in mRNP complexes derived from the neuroendocrine rat PC12 cells. Furthermore, biolayer interferometry was used to determine the K_D of selected Annexin-RNA interactions, which indicated distinct affinities. Amongst these Annexins, Annexin A13 and the core structures of Annexin A7, Annexin A11 bind c-myc 3'UTR with K_Ds in the nanomolar range. Of the selected Annexins, only Annexin A2 binds the c-myc 5'UTR indicating some selectivity. Discussion: The oldest members of the mammalian Annexin family share the ability to associate with RNA, suggesting that RNA-binding is an ancient trait of this protein family. Thus, the combined RNA- and lipid-binding properties of the Annexins make them attractive candidates to participate in coordinated long-distance transport of membrane vesicles and mRNAs regulated by Ca²⁺. The present screening results can thus pave the way for studies of the multifunctional Annexins in a novel cellular context.

Inhibition of Annexin A10 Contributes to ZNF281 Mediated Aggressiveness of Hepatocellular Carcinoma

Objective

To investigate the involvement and transcriptional targets of zinc finger protein 281 (ZNF281) in the progression of hepatocellular carcinoma (HCC).

Methods

The expression of ZNF281 in HCC was detected in tissue microarray and cell lines. The role of ZNF281 in aggressiveness of HCC was examined using wound healing, matrigel transwell, pulmonary metastasis model and assays for expression of EMT markers. RNA-seq was used to find potential target gene of ZNF281. Chromatin immunoprecipitation (ChIP) assay and co-immunoprecipitation (Co-IP) were employed to uncover the mechanism of the transcriptional regulation of ZNF281 on the target gene.

Results

ZNF281 was increased in tumor tissues and positively correlated with vascular invasion in HCC. Knockdown of ZNF281 suppressed the migration and invasion with significant alteration of EMT marker expression in HLE and Huh7 HCC cell lines. RNA-seq screening showed that the tumor suppressor gene Annexin A10 (ANXA10) was a most up-regulated gene in response to ZNF281 depletion and responsible for the attenuation of aggressiveness. Mechanistically, ZNF281 interacted with the ANXA10 promoter region harboring ZNF281 recognition sites, and recruited components of nucleosome remodeling and deacetylation (NuRD) complex. By knocking down such components like HDAC1 or MTA1, ANXA10 was released from transcriptional repression by ZNF281/NuRD, and in turn reversed the EMT, invasion and metastasis driven by ZNF281.

Conclusion

ZNF281 drives invasion and metastasis of HCC partially through transcriptional repression of tumor suppressor gene ANXA10 by recruiting NuRD complex.

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.

PredictiveNetwork: predictive gene network estimation with application to gastric cancer drug response-predictive network analysis

Background

Gene regulatory networks have garnered a large amount of attention to understand disease mechanisms caused by complex molecular network interactions. These networks have been applied to predict specific clinical characteristics, e.g., cancer, pathogenicity, and anti-cancer drug sensitivity. However, in most previous studies using network-based prediction, the gene networks were estimated first, and predicted clinical characteristics based on pre-estimated networks. Thus, the estimated networks cannot describe clinical characteristic-specific gene regulatory systems. Furthermore, existing computational methods were developed from algorithmic and mathematics viewpoints, without considering network biology.

Results

To effectively predict clinical characteristics and estimate gene networks that provide critical insights into understanding the biological mechanisms involved in a clinical characteristic, we propose a novel strategy for predictive gene network estimation. The proposed strategy simultaneously performs gene network estimation and prediction of the clinical characteristic. In this strategy, the gene network is estimated with minimal network estimation and prediction errors. We incorporate network biology by assuming that neighboring genes in a network have similar biological functions, while hub genes play key roles in biological processes. Thus, the proposed method provides interpretable prediction results and enables us to uncover biologically reliable marker identification. Monte Carlo simulations shows the effectiveness of our method for feature selection in gene estimation and prediction with excellent prediction accuracy. We applied the proposed strategy to construct gastric cancer drug-responsive networks.

Conclusion

We identified gastric drug response predictive markers and drug sensitivity/resistance-specific markers, AKR1B10, AKR1C3, ANXA10, and ZNF165, based on GDSC data analysis. Our results for identifying drug sensitive and resistant specific molecular interplay are strongly supported by previous studies. We expect that the proposed strategy will be a useful tool for uncovering crucial molecular interactions involved a specific biological mechanism, such as cancer progression or acquired drug resistance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12859-022-04871-z.

Annexin Animal Models-From Fundamental Principles to Translational Research

Routine manipulation of the mouse genome has become a landmark in biomedical research. Traits that are only associated with advanced developmental stages can now be investigated within a living organism, and the in vivo analysis of corresponding phenotypes and functions advances the translation into the clinical setting. The annexins, a family of closely related calcium (Ca²⁺)- and lipid-binding proteins, are found at various intra- and extracellular locations, and interact with a broad range of membrane lipids and proteins. Their impacts on cellular functions has been extensively assessed in vitro, yet annexin-deficient mouse models generally develop normally and do not display obvious phenotypes. Only in recent years, studies examining genetically modified annexin mouse models which were exposed to stress conditions mimicking human disease often revealed striking phenotypes. This review is the first comprehensive overview of annexin-related research using animal models and their exciting future use for relevant issues in biology and experimental medicine.

The involvement of spinal annexin A10/NF-κB/MMP-9 pathway in the development of neuropathic pain in rats

Background

Neuropathic pain (NP) is a prevalent disease, which badly impairs the life quality of patients. The underlying mechanism of NP is still not fully understood. It has been reported that spinal Annexin A10 (ANXA10) contributes to NP. This study aims at exploring the underlying mechanisms of spinal ANXA10 in regulating NP in rats.

Methods

Spinal nerve ligation (SNL) was adopted to establish a NP model in rats. After SNL, paw withdrawal threshold and paw withdrawal latency were recorded to measure pain behaviors, RT-PCR was used to check the change of the expression of spinal ANXA10 mRNA, western blot analysis was used to detect the change of the protein level of ANXA10, nuclear factor kappa B (NF-κB), and maisrix metalloproteinase-9 (MMP-9) in the spinal cord. The levels of proinflammatory cytokines, including tumor necrosis factor-α (TNF-α), interleukine-1β (IL-1β), and interleukine-6 (IL-6), were explored by ELISA kits. The effects of both knockdown of spinal ANXA10 and inhibition of NF-κB on pain behaviors and the expression of MMP-9 and proinflammatory cytokines were investigated.

Results

Our present findings highlighted that SNL caused pain hypersensitivity and increased the expression of spinal ANXA10/pNF-κB, TNF-α, IL-1β, and IL-6 both in the early and late phase of NP in rats, while spinal MMP-9 was only slightly increased in the early phase of NP. Knockdown of ANXA10 at the spinal cord level suppressed the SNL-induced hyperalgesia and blocked the activation of NF-κB, TNF-α and IL-1β both in the early and late phase of NP. Spinal ANXA10 knockdown could prevent the upregulation of spinal MMP-9 in the early phase and inhibit IL-6 expression in the late phase of SNL-induced NP.

Conclusions

In conclusion, spinal ANXA10/NF-κB/MMP-9 pathway, along with the activation of proinflammatory cytokines, was involved in the SNL-induced NP. MMP-9 may act as the downstream target of ANXA10/NF-κB pathway in the development rather than the maintenance of NP.

Annexins in Translational Research: Hidden Treasures to Be Found

The vertebrate annexin superfamily (AnxA) consists of 12 members of a calcium (Ca²⁺) and phospholipid binding protein family which share a high structural homology. In keeping with this hallmark feature, annexins have been implicated in the Ca²⁺-controlled regulation of a broad range of membrane events. In this review, we identify and discuss several themes of annexin actions that hold a potential therapeutic value, namely, the regulation of the immune response and the control of tissue homeostasis, and that repeatedly surface in the annexin activity profile. Our aim is to identify and discuss those annexin properties which might be exploited from a translational science and specifically, a clinical point of view.

Functional Association between Regulatory RNAs and the Annexins

Cells respond to pathophysiological states by activation of stress-induced signalling. Regulatory non-coding microRNAs (miRNAs) often form stable feed-forward loops which ensure prolongation of the signal, contributing to sustained activation. Members of the annexin protein family act as sensors for Ca²⁺, pH, and lipid second messengers, and regulate various signalling pathways. Recently, annexins were reported to participate in feedback loops, suppressing miRNA synthesis and attenuating stress-induced dysregulation of gene expression. They can directly or indirectly associate with RNAs, and are transferred between the cells in exosomes and shed microvesicles. The ability of annexins to recruit other proteins and miRNAs into exosomes implicates them in control of cell–cell interactions, affecting the adaptive responses and remodelling processes during disease. The studies summarized in this Review point to an emerging role of annexins in influencing the synthesis, localisation, and transfer of regulatory RNAs.

Simvastatin Up-Regulates Annexin A10 That Can Inhibit the Proliferation, Migration, and Invasion in Androgen-Independent Human Prostate Cancer Cells

BACKGROUND

Statins have recently been studied for their proapoptotic and antimetastatic effects. However, the exact mechanisms of their anticancer actions remain unclear. Using microarrays, we discovered up-regulation of annexin A10 (ANXA10) in PC-3 cells after simvastatin treatment. ANXA10 reportedly has antitumor effects. In this study, we evaluated the effects of simvastatin on ANXA10 signaling in androgen-independent prostate cancer cells.

METHODS

PC-3, LNCaP-LA (which were derived from LNCaP cells and cultured in 10% charcoal-stripped fetal bovine serum for 3 months), and DU145 human prostate cancer cell lines were used. Prostate tissues were collected from 60 patients (benign prostatic hyperplasia [BPH], n = 20; prostate cancer with a Gleason score of 7, n = 20; prostate cancer with a Gleason score of 8-10, n = 20) at the time of prostate biopsies performed. We used a nude mouse tumor xenograft model with administration of simvastatin or phosphate-buffered saline via intraperitoneal injection.

RESULTS

Simvastatin inhibited the proliferation, migration, and invasion of PC-3, LNCaP-LA, and DU145 cells. The expression level of ANXA10 was up-regulated by simvastatin in PC-3, LNCaP-LA, and DU145 cells. Transfection with ANXA10 inhibited PC-3 and LNCaP-LA cells proliferation, migration, and invasion. Knockdown of ANXA10 by siRNA increased the proliferation of PC-3 and LNCaP-LA cells. In a nude mouse xenograft model of PC-3 cells, simvastatin induced both reduction in the tumor size and up-regulation of ANXA10 expression. In human prostate biopsy samples, ANXA10 mRNA expression was significantly lower in the prostate cancer group than in the BPH group. Next, we found that up-regulation of ANXA10 in PC-3 resulted in down-regulation of S100 calcium binding protein A4 (S100A4), which is reportedly correlated with aggressiveness and a worse prognosis for patients with different types of carcinomas. Expression of S100A4 was down-regulated by simvastatin. In PC-3 cells, knockdown of S100A4 by siRNA inhibited the proliferation, migration, and invasion of PC-3 cells.

CONCLUSION

Our results suggest that statins inhibit the proliferation, migration, and invasion of androgen-independent prostate cancer cells by up-regulation of ANXA10. Additionally, it is possible that S100A4 plays a role in these effects. Statins may be beneficial in the prevention and/or treatment of prostate cancer. Prostate 77: 337-349, 2017. © 2016 Wiley Periodicals, Inc.

Loss of maternal ANNEXIN A10 via a 34-kb deleted-type copy number variation is associated with embryonic mortality in Japanese Black cattle

Background

Conception is a fundamental trait for successful cattle reproduction. However, conception rates in Japanese Black cattle have been gradually declining over the last two decades. Although conception failures are mainly caused by embryonic mortality, the role of maternal genetic factors in the process remains unknown. Copy number variation (CNV), defined as large-scale genomic structural variants, contributes to several genetic disorders. To identify CNV associated with embryonic mortality in Japanese Black cattle, we evaluated embryonic mortality as a categorical trait with a threshold model and conducted a genome-wide CNV association study for embryonic mortality using 791 animals.

Results

We identified a deleted-type CNV ranging from 378,127 to 412,061 bp on bovine chromosome 8, which was associated with embryonic mortality at 30–60 days after artificial insemination (AI). The CNV harbors exon 2 to 6 of ANNEXIN A10 (ANXA10). Analysis of sequence traces from the CNV identified that 63 bp reads bridging the breakpoint were present on both sides of the CNV, indicating that the CNV was generated by non-allelic homologous recombination using the 63 bp homologous sequences. Western blot analysis showed that the CNV results in a null allele of ANXA10. This association was replicated using a sample population size of 2552 animals. To elucidate the function of ANXA10 in vivo, we generated Anxa10 null mice using the CRISPR/Cas9 system. Crossbreeding experiments showed that litter size from crosses of both Anxa10^-/- and Anxa10^+/- females had fewer pups than did Anxa10^+/+ females, and embryos of Anxa10^-/- females died between implantation stages E4.5 and E12.5. These results indicate that loss of maternal Anxa10 causes embryonic mortality.

Conclusions

This study identified a deleted-type CNV encompassing ANXA10 in cows that was associated with embryonic mortality at 30–60 days after AI. Using a mouse model, we confirmed that litter sizes were smaller in crosses of both Anxa10^-/- and Anxa10^+/- females relative to those of wild females. These results indicate that ANXA10 is a maternal factor that is critical for embryo development.

Electronic supplementary material

The online version of this article (doi:10.1186/s12864-016-3312-z) contains supplementary material, which is available to authorized users.

NEAT1 modulates herpes simplex virus-1 replication by regulating viral gene transcription

Nuclear paraspeckle assembly transcript 1 (NEAT1) is the crucial structural platform of paraspeckles, which is one type of nuclear bodies. As a stress-induced lncRNA, the expression of NEAT1 increases in response to viral infection, but little is known about the role of NEAT1 or paraspeckles in the replication of herpes simplex virus-1 (HSV-1). Here, we demonstrate that HSV-1 infection increases NEAT1 expression and paraspeckle formation in a STAT3-dependent manner. NEAT1 and other paraspeckle protein components, P54nrb and PSPC1, can associate with HSV-1 genomic DNA. By binding with STAT3, PSPC1 is required for the recruitment of STAT3 to paraspeckles and facilitates the interaction between STAT3 and viral gene promoters, finally increasing viral gene expression and viral replication. Furthermore, thermosensitive gel containing NEAT1 siRNA or STAT3 siRNA effectively healed the skin lesions caused by HSV-1 infection in mice. Our results provide insight into the roles of lncRNAs in the epigenetic control of viral genes and into the function of paraspeckles.

Annexin A10 is involved in the development and maintenance of neuropathic pain in mice

ANXA10 (annexin A10) is a member of the annexin family, and its biological effects are mediated primarily through the calcium-dependent phospholipid-binding and calcium ion binding. We examined the gene expressions of the L5 spinal cord after spinal nerve ligation (SNL)-induced neuropathic pain in mice by gene chip. The results showed that Anxa10 mRNA was the most upregulated gene in annexin family with 73.7-fold increase. Although previous studies have reported that several annexins are involved in nociceptive pain, the role of Anxa10 in pain remains undefined. We aimed to evaluate the role of ANXA10 in mediating injury-induced heat hyperalgesia and mechanical allodynia. We found that SNL induced persistent upregulation of Anxa10 mRNA and protein in the spinal cord of mice. Moreover, ANXA10 was colocalized with the neuronal marker MAP2 and astrocytic marker glial fibrillary acidic protein (GFAP), but not with microglial marker CD11b. Finally, pretreatment with Anxa10 siRNA partially prevented SNL-induced mechanical allodynia and heat hyperalgesia. Posttreatment with Anxa10 siRNA attenuated SNL-induced neuropathic pain. These findings suggest that ANXA10 might be a novel target in the treatment of neuropathic pain.

Reactive oxygen species exert opposite effects on Tyr23 phosphorylation of the nuclear and cortical pools of annexin A2

Annexin A2 (AnxA2) is a multi-functional and -compartmental protein whose subcellular localisation and functions are tightly regulated by its post-translational modifications. AnxA2 and its Tyr23-phosphorylated form (pTyr23AnxA2) are involved in malignant cell transformation, metastasis and angiogenesis. Here, we show that H₂O₂ exerts rapid, simultaneous and opposite effects on the Tyr23 phosphorylation status of AnxA2 in two distinct compartments of rat pheochromocytoma (PC12) cells. Reactive oxygen species induce dephosphorylation of pTyr23AnxA2 located in the PML bodies of the nucleus, whereas AnxA2 associated with F-actin at the cell cortex is Tyr23 phosphorylated. The H₂O₂-induced responses in both compartments are transient and the pTyr23AnxA2 accumulating at the cell cortex is subsequently incorporated into vesicles and then released to the extracellular space. Blocking nuclear export by leptomycin B does not affect the nuclear pool of pTyr23AnxA2, but increases the amount of total AnxA2 in this compartment, indicating that the protein might have several functions in the nucleus. These results suggest that Tyr23 phosphorylation can regulate the function of AnxA2 at distinct subcellular sites.

Summary: Reactive oxygen species cause two opposite and transient Tyr23-based modifications of annexin A2; its dephosphorylation in the nucleus and phosphorylation at the cell cortex, resulting in release of the protein in exosomes.

Annexin A10 is a marker for the serrated pathway of colorectal carcinoma

Serrated adenocarcinoma (SAC), representing at least 10 % of colorectal carcinomas (CRC), differs from conventional carcinomas not only by its histology, but also by its molecular basis. However, the diagnosis of SAC in poorly differentiated cases and without an adjacent serrated adenoma can be challenging. In this study, we utilized previously described expression data and identified annexin A10 (ANXA10) as a potential marker for SAC. We conducted ANXA10 immunohistochemistry in groups of 146 CRC patients and 131 serrated and conventional polyps. In CRC cases, ANXA10 expression associated with serrated histology (sensitivity 42 % and specificity 98 %). BRAF V600E mutation correlated with ANXA10 expression but also seven BRAF wild-type tumors (5 %) were positive for ANXA10. Immunoreactivity for either ANXA10 or BRAF V600E was an accurate predictor of serrated histology (sensitivity 55 % and specificity 97 %). ANXA10 expression did not associate with tumor stage or grade. Of the 131 colorectal polyps, 30/30 of sessile serrated adenomas, 6/11 traditional serrated adenomas, 20/32 hyperplastic polyps, and 2/27 tubulovillous adenomas were positive for ANXA10, while 31/31 tubular adenomas were negative. In conclusion, the results suggest that ANXA10 is a marker with high specificity for the serrated pathway of CRC.

Annexin A10 is a marker for the serrated pathway of colorectal carcinoma

Serrated adenocarcinoma (SAC), representing at least 10 % of colorectal carcinomas (CRC), differs from conventional carcinomas not only by its histology, but also by its molecular basis. However, the diagnosis of SAC in poorly differentiated cases and without an adjacent serrated adenoma can be challenging. In this study, we utilized previously described expression data and identified annexin A10 (ANXA10) as a potential marker for SAC. We conducted ANXA10 immunohistochemistry in groups of 146 CRC patients and 131 serrated and conventional polyps. In CRC cases, ANXA10 expression associated with serrated histology (sensitivity 42 % and specificity 98 %). BRAF V600E mutation correlated with ANXA10 expression but also seven BRAF wild-type tumors (5 %) were positive for ANXA10. Immunoreactivity for either ANXA10 or BRAF V600E was an accurate predictor of serrated histology (sensitivity 55 % and specificity 97 %). ANXA10 expression did not associate with tumor stage or grade. Of the 131 colorectal polyps, 30/30 of sessile serrated adenomas, 6/11 traditional serrated adenomas, 20/32 hyperplastic polyps, and 2/27 tubulovillous adenomas were positive for ANXA10, while 31/31 tubular adenomas were negative. In conclusion, the results suggest that ANXA10 is a marker with high specificity for the serrated pathway of CRC.