Actin-binding Protein Anillin Research Articles

Identification and validation of novel prognostic biomarkers and therapeutic targets for non-small cell lung cancer.

Background: Despite the significant survival benefits of anti-PD-1/PD-L1 immunotherapy, non-small cell lung cancer (NSCLC) remains one of the most common tumors and major causes of cancer-related deaths worldwide. Thus, there is an urgent need to identify new therapeutic targets for this refractory disease. Methods: In this study, microarray datasets GSE27262, GSE75037, GSE102287, and GSE21933 were integrated by Venn diagram. We performed functional clustering and pathway enrichment analyses using R. Through the STRING database and Cytoscape, we conducted protein-protein interaction (PPI) network analysis and identified the key genes, which were verified by the GEPIA2 and UALCAN portal. Validation of actin-binding protein anillin (ANLN) was performed by quantitative real-time polymerase chain reaction and Western blotting. Additionally, Kaplan-Meier methods were used to compute the survival analyses. Results: In total, 126 differentially expressed genes were identified, which were enriched in mitotic nuclear division, mitotic cell cycle G2/M transition, vasculogenesis, spindle, and peroxisome proliferator-activated receptor signaling pathway. 12 central node genes were identified in the PPI network complex. The survival analysis revealed that high transcriptional levels were associated with inferior survival in NSCLC patients. The clinical implication of ANLN was further explored; its protein expression showed a gradually increasing trend from grade I to III. Conclusion: These Key genes may be involved in the carcinogenesis and progression of NSCLC, which may serve as useful targets for NSCLC diagnosis and treatment.

Native Size-Exclusion Chromatography–Based Mass Spectrometry Reveals New Components of the Early Heat Shock Protein 90 Inhibition Response Among Limited Global Changes

The molecular chaperone heat shock protein 90 (HSP90) works in concert with co-chaperones to stabilize its client proteins, which include multiple drivers of oncogenesis and malignant progression. Pharmacologic inhibitors of HSP90 have been observed to exert a wide range of effects on the proteome, including depletion of client proteins, induction of heat shock proteins, dissociation of co-chaperones from HSP90, disruption of client protein signaling networks, and recruitment of the protein ubiquitylation and degradation machinery—suggesting widespread remodeling of cellular protein complexes. However, proteomics studies to date have focused on inhibitor-induced changes in total protein levels, often overlooking protein complex alterations. Here, we use size-exclusion chromatography in combination with mass spectrometry (SEC-MS) to characterize the early changes in native protein complexes following treatment with the HSP90 inhibitor tanespimycin (17-AAG) for 8 h in the HT29 colon adenocarcinoma cell line. After confirming the signature cellular response to HSP90 inhibition (e.g., induction of heat shock proteins, decreased total levels of client proteins), we were surprised to find only modest perturbations to the global distribution of protein elution profiles in inhibitor-treated HT29 cells at this relatively early time-point. Similarly, co-chaperones that co-eluted with HSP90 displayed no clear difference between control and treated conditions. However, two distinct analysis strategies identified multiple inhibitor-induced changes, including known and unknown components of the HSP90-dependent proteome. We validate two of these—the actin-binding protein Anillin and the mitochondrial isocitrate dehydrogenase 3 complex—as novel HSP90 inhibitor-modulated proteins. We present this dataset as a resource for the HSP90, proteostasis, and cancer communities (https://www.bioinformatics.babraham.ac.uk/shiny/HSP90/SEC-MS/), laying the groundwork for future mechanistic and therapeutic studies related to HSP90 pharmacology. Data are available via ProteomeXchange with identifier PXD033459.

Actin-binding protein anillin promotes the progression of hepatocellular carcinoma in vitro and in mice.

Hepatocellular carcinoma (HCC) is a common type of tumor with high mortality worldwide. Investigations associated with the molecular etiology of HCC and screening novel therapeutic targets are still urgently in need. Anillin (ANLN), as a type of evolutionarily conserved actin-binding protein, is involved in multiple cellular processes. ANLN widely affected the progression and metastasis of several types of cancer, and its overexpression was frequently demonstrated in previous studies. The present study demonstrated high expression of ANLN in human HCC tissues, which was also associated the prognosis of patients with HCC. The associations between ANLN expression and the clinicopathological features were determined, including the number of tumor nodes (P=0.011) and tumor size (P=0.003) of patients with HCC. It was found that ANLN promoted cell proliferation, invasion and migration of HCC cells in vitro, and affected tumor growth in vivo. Therefore, ANLN is suggested as a promising therapeutic target for the treatment of HCC.

Actin-binding protein Anillin promotes the progression of gastric cancer in vitro and in mice.

BackgroundTo detect the expression levels of actin‐binding protein anillin (ANLN) in human gastric cancer (GC) tissues and explore the possible involvement of ANLN in GC cell proliferation, migration, and invasion.MethodsThe bioinformation analysis was performed in TCGA database to explore the expression of ANLN in human GC tissues and the difference of ANLN expression between multiple types of cancers. IHC assays and clinical pathological analysis were performed to confirm ANLN expression and its correlation with clinical features of GC patients. Colony formation, CCK‐8, wound closure, and transwell assays were performed to detect its effects on GC cell proliferation, migration, and invasion in vitro. Tumor growth was also measured using a xenograft animal model.ResultsWe found the high expression of ANLN in human GC tissues based on the results from TCGA database and IHC staining. We further noticed ANLN depletion resulted in the inhibition of GC cell proliferation, migration, and invasion. Our data further confirmed that ANLN contributed to tumor growth of GC cells in vivo.ConclusionsWe confirmed the involvement of ANLN in GC progression and thought ANLN could serve as a promising therapeutic target for GC.

ANLN Directly Interacts with RhoA to Promote Doxorubicin Resistance in Breast Cancer Cells.

BackgroundChemotherapy resistance is the leading cause of cancer treatment failure. This research was conducted to explore a potential link between actin-binding protein anillin (ANLN) and doxorubicin resistance in breast cancer.Materials and MethodsWe compared ANLN expression and 50% inhibition concentration (IC50) of doxorubicin in human breast cancer cells (MDA-MB-231) and human breast cancer cells with doxorubicin resistance (MDA-MB-231/ADM). Co-immunoprecipitation was used to investigate the interaction between ANLN and RhoA. The cell viability, apoptosis, gene and protein expression were estimated by MTT, flow cytometry, quantitative real-time PCR and western blot.ResultsThe doxorubicin resistance in MDA-MB-231/ADM cells (IC50 = 19.40 ± 1.16 μg/mL) was significantly higher than that in MDA-MB-231 cells (IC50 = 1.65 ± 0.23 μg/mL). ANLN was up-regulated in MDA-MB-231/ADM cells compared to MDA-MB-231 cells. Furthermore, ANLN overexpression promoted cell viability and inhibited apoptosis of MDA-MB-231 cells. The gene and protein expression of multidrug resistance (MDR1) and cancer resistance protein (BCRP) were enhanced by ANLN overexpression in MDA-MB-231 cells. ANLN silencing suppressed cell viability and the expression of MDR1 and BCRP and facilitated apoptosis in MDA-MB-231/ADM cells. Moreover, ANLN promoted RhoA activation by interacting with RhoA. ANLN up-regulation enhanced cell viability and the expression of MDR1 and BCRP and decreased apoptosis of MDA-MB-231 cells. The influence conferred by ANLN overexpression was effectively abolished by C3 transferase.ConclusionThis work revealed that ANLN promoted doxorubicin resistance in breast cancer cells by activating RhoA. Thus, our study suggests a novel target for breast cancer treatment.

Anillin facilitates cell proliferation and induces tumor growth of hepatocellular carcinoma via miR-138/SOX4 axis regulation.

Actin-binding protein Anillin plays a pivotal role in regulating cytokinesis during the cell cycle, and involves in tumorigenesis and progress. However, the exact regulation mechanism of Anillin in human hepatocellular carcinoma (HCC) remains largely unknown. In this study, we examined and verified the anomalous high expression of Anillin in both HCC patients' specimens and HCC cell lines. High expression of Anillin is associated with dismal clinicopathologic features of HCC patients and poor prognosis. We conducted loss-of and gain-of function studies in HCC Hep3B cells. Anillin presented a significantly facilitating effect on cell proliferation in vitro and induced remarkable tumor growth in vivo. We found that the over-expression of Anillin was driven by a potential axis of miR-138/SOX4. Transcription factor SOX4 presented a high expression profile positive correlated with Anillin, and ChIP assay validated the interaction between SOX4 and the specific sequence of the promoter region of Anillin gene. While, we verified miR-138 as an upstream regulator of SOX4, which is abrogated in HCC cells and exerts degenerating effect on SOX4 mRNA. In our conclusion, Anillin facilitates the cell proliferation and enhances tumor growth of HCC, and is modulated by miR-138/SOX4 axis which regulates the transcriptional activity of Anillin. Findings above demonstrate us a probable axis for HCC diagnosis and treatment.Summary of the main pointAnillin facilitates the cell proliferation and enhances tumor growth in HCC. The transcriptional activity of Anillin is modulated by miR-138/SOX4 axis. Findings above demonstrate us a probable axis for HCC diagnosis and treatment.

Visualizing Dynamic Actin Crosslinking Processes Driven by the Actin Binding Protein Anillin

Anillin is an actin binding protein that can bundle actin filaments and associate with the plasma membrane in the ring-like actin network. Anillin can be divided into a membrane-bound domain and an actin binding domain (ABD). Although the ABD in anillin plays an important role in the dynamic ring transition, it is unclear how the ABD interacts with the actin ring structures during the contractile ring to midbody ring transition. In order to elucidate the underlying intermolecular interactions between the ABD and actin filaments, it is necessary to observe dynamic crosslinking processes. Here, we performed real-time imaging of actin filament crosslinking dynamics by the ABD of anillin using total internal reflection fluorescence microscopy (TIRFM) and high-speed atomic force microscopy (Hs-AFM) for single-molecule imaging. Both human full-length anillin and anillin N-terminal ABD constructs existed as monomers and showed relatively low binding affinity for actin filaments. Hs-AFM showed that anillin monomers crosslinked with actin filaments at a distance of 8 nm. The distance between the aligned crosslinked anillin molecules was approximately 37 nm, which corresponded to the half pitch of an actin filament. Furthermore, the polarity of these filaments was both parallel and antiparallel. Our direct and dynamic high-resolution visualization of the actin crosslinking process provides a powerful new approach to studying the interactions and dynamics of biomolecules.

Visualizing dynamic actin cross-linking processes driven by the actin-binding protein anillin.

Anillin is a type of actin filament cross-linking protein that stabilizes the actin-based contractile ring during cytokinesis. To elucidate the underlying intermolecular interactions between actin filaments and anillin, we utilized total internal reflection fluorescence microscopy (TIRFM) and high-speed atomic force microscopy (Hs-AFM). Single-molecule imaging of anillin using TIRFM showed that anillin exists as monomers with relatively low binding affinity for actin filaments. Real-time imaging of actin filament cross-linking dynamics induced by anillin using Hs-AFM revealed that anillin monomers cross-link with actin filaments at a distance of 8nm and that the polarity of those filaments is both parallel and antiparallel. These results are consistent with anillin playing a role in actin ring transition invivo, where it might be responsible for thinning the ring-shaped apolar actin bundles.

Regulation of actin-binding protein ANLN by antitumor miR-217 inhibits cancer cell aggressiveness in pancreatic ductal adenocarcinoma.

Analysis of our microRNA (miRNA) expression signature of pancreatic ductal adenocarcinoma (PDAC) revealed that microRNA-217 (miR-217) was significantly reduced in cancer tissues. The aim of this study was to investigate the antitumor roles of miR-217 in PDAC cells and to identify miR-217-mediated molecular pathways involved in PDAC aggressiveness. The expression levels of miR-217 were significantly reduced in PDAC clinical specimens. Ectopic expression of miR-217 significantly suppressed cancer cell migration and invasion. Transcription of actin-binding protein Anillin (coded by ANLN) was detected by our in silico and gene expression analyses. Moreover, luciferase reporter assays showed that ANLN was a direct target of miR-217 in PDAC cells. Overexpression of ANLN was detected in PDAC clinical specimens by real-time PCR methods and immunohistochemistry. Interestingly, Kaplan–Meier survival curves showed that high expression of ANLN predicted shorter survival in patients with PDAC by TCGA database analysis. Silencing ANLN expression markedly inhibited cancer cell migration and invasion capabilities of PDAC cell lines. We further investigated ANLN-mediated downstream pathways in PDAC cells. “Focal adhesion” and “Regulation of actin binding protein” were identified as ANLN-modulated downstream pathways in PDAC cells. Identification of antitumor miR-217/ANLN-mediated PDAC pathways will provide new insights into the potential mechanisms underlying the aggressive course of PDAC.

Functional analysis of the nasopharyngeal carcinoma primary tumor‑associated gene interaction network.

The aim of the present study was to investigate the molecular mechanism of nasopharyngeal carcinoma (NPC) primary tumor development through the identification of key genes using bioinformatics approaches. Using the GSE53819 microarray dataset, acquired from the Gene Expression Omnibus database, differentially expressed genes (DEGs) were screened out between NPC primary tumor and control samples, followed by hierarchical clustering analysis. The Search Tool for the Retrieval of Interacting Genes database was utilized to build a protein-protein interaction network to identify key node proteins. In total, 1,067 DEGs, including 326 upregulated genes and 741 downregulated genes, were identified between the NPC and control samples. The results of the hierarchical clustering analysis demonstrated that 95% of the DEGs were sample-specific. Furthermore, PDZ binding kinase (PBK), centromere protein F (CENPF), actin-binding protein anillin (ANLN), exonuclease 1 (EXO1) and chromosome 15 open reading frame 42 (C15ORF42) were included in the obtained network module, which was closely associated with the cell cycle and nucleic acid metabolic process GO functions. The results of the present study revealed that EXO1, CENPF, ANLN, PBK and C15ORF42 may be involved in the mechanism of NPC via modulating the cell cycle and nucleic acid metabolic processes, and may serve as molecular biomarkers for the diagnosis of this disease.

In silico analysis of expression pattern of a Wnt/β-catenin responsive gene ANLN in gastric cancer.

Actin-binding protein anillin (ANLN) is primarily involved in the cytokinesis and known to be dysregulated in many cancers including gastric cancer (GC). However, the regulation and clinical significance of ANLN in GC are far less clear. In the present study, we aimed to investigate the clinical significance and possible regulators of ANLN in GC. We have identified the Wnt/β-catenin associated regulation of ANLN by analyzing the in vitro perturbed β-catenin mRNA expression profiles. Investigating the gastric tumors from publicly available genome-wide mRNA expression profiles, we have identified the over expression of ANLN in gastric tumors. Association between ANLN expression and clinical characteristics of GC showed elevated expression in intestinal type GC. Performing a single sample prediction method across GC mRNA expression profiles, we have identified the over expression of ANLN in proliferative type gastric tumors compared to the invasive and metabolic type gastric tumors. In silico pathway prediction analysis revealed the association between Wnt/β-catenin signaling and ANLN expression in gastric tumors. Our results highlight that expression of a Wnt/β-catenin responsive gene ANLN in GC is a molecular predictor of intestinal and proliferative type gastric tumors.

Development of Biomarkers for Screening Hepatocellular Carcinoma Using Global Data Mining and Multiple Reaction Monitoring

Hepatocellular carcinoma (HCC) is one of the most common and aggressive cancers and is associated with a poor survival rate. Clinically, the level of alpha-fetoprotein (AFP) has been used as a biomarker for the diagnosis of HCC. The discovery of useful biomarkers for HCC, focused solely on the proteome, has been difficult; thus, wide-ranging global data mining of genomic and proteomic databases from previous reports would be valuable in screening biomarker candidates. Further, multiple reaction monitoring (MRM), based on triple quadrupole mass spectrometry, has been effective with regard to high-throughput verification, complementing antibody-based verification pipelines. In this study, global data mining was performed using 5 types of HCC data to screen for candidate biomarker proteins: cDNA microarray, copy number variation, somatic mutation, epigenetic, and quantitative proteomics data. Next, we applied MRM to verify HCC candidate biomarkers in individual serum samples from 3 groups: a healthy control group, patients who have been diagnosed with HCC (Before HCC treatment group), and HCC patients who underwent locoregional therapy (After HCC treatment group). After determining the relative quantities of the candidate proteins by MRM, we compared their expression levels between the 3 groups, identifying 4 potential biomarkers: the actin-binding protein anillin (ANLN), filamin-B (FLNB), complementary C4-A (C4A), and AFP. The combination of 2 markers (ANLN, FLNB) improved the discrimination of the before HCC treatment group from the healthy control group compared with AFP. We conclude that the combination of global data mining and MRM verification enhances the screening and verification of potential HCC biomarkers. This efficacious integrative strategy is applicable to the development of markers for cancer and other diseases.

Abstract 390: Expression of the actin-binding protein Anillin is a prognostic biomarker for primary ER positive breast cancer.

Abstract Identification of novel prognostic and predictive factors is important for individualizing prognosis and treatment for cancer patients. The present study aimed at examining the potential prognostic value of Anillin (ANLN) expression in breast cancer. ANLN, an actin-binding protein required for cytokinesis, was discovered using the Human Protein Atlas as being differentially expressed in breast cancer and, thus, a potential prognostic biomarker. The purpose of the Human Protein Atlas project (www.proteinatlas.org) is to generate validated antibodies towards the entire human proteome and to use these antibodies for protein profiling in normal tissues and cancer cells. The freely available Human Protein Atlas provides an opportunity to use antibody-based proteomics as a high-throughput strategy to discover novel cancer biomarkers of potential clinical relevance. ANLN has been shown to be up-regulated in several human tumor types including lung, renal and pancreatic tumors. For the purpose of the current study, tissue microarrays with tumor samples from three independent breast cancer cohorts were analyzed by immunohistochemistry (IHC). SiRNA mediated ANLN knockdown of breast cancer cell lines followed by western blot or IHC on cytospin was done for antibody validation. Cell viability assay and cell cycle assay was used to study the function of ANLN knocked breast cancer cells. The majority of breast tumors displayed moderate to strong nuclear positivity in slightly varying fractions, generally below 25%. High nuclear fraction of ANLN was associated with large tumor size, high histological grade, high proliferation and estrogen receptor (ER) negativity. Furthermore, high nuclear expression of ANLN was significantly associated with poor prognosis for patients with ER positive breast tumors in all three cohorts. SiRNA mediated ANLN knockdown was found to induce low cell viability for ER positive breast cancer cells but not for ER negative breast cancer cells. In addition, cell cycle studies showed that ANLN knockdown yielded a shift to G2/M phase, in both ER positive and ER negative breast cancer cells. In conclusion, our results strongly suggest that ANLN can be used as a prognostic biomarker for ER positive breast cancer patients. Citation Format: Kristina Magnusson, Gabriela Gremel, Fredrik Pontén, Karin Jirström. Expression of the actin-binding protein Anillin is a prognostic biomarker for primary ER positive breast cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 390. doi:10.1158/1538-7445.AM2013-390

Citron kinase controls abscission through RhoA and anillin

The small GTPase RhoA plays a crucial role in the different stages of cytokinesis, including contractile ring formation, cleavage furrow ingression, and midbody abscission. Citron kinase (CIT-K), a protein required for cytokinesis and conserved from insects to mammals, is currently considered a cytokinesis-specific effector of active RhoA. In agreement with previous observations, we show here that, as in Drosophila cells, CIT-K is specifically required for abscission in mammalian cells. However, in contrast with the current view, we provide evidence that CIT-K is an upstream regulator rather than a downstream effector of RhoA during late cytokinesis. In addition, we show that CIT-K is capable of physically and functionally interacting with the actin-binding protein anillin. Active RhoA and anillin are displaced from the midbody in CIT-K-depleted cells, while only anillin, but not CIT-K, is affected if RhoA is inactivated in late cytokinesis. The overexpression of CIT-K and of anillin leads to abscission delay. However, the delay produced by CIT-K overexpression can be reversed by RhoA inactivation, while the delay produced by anillin overexpression is RhoA-independent. Altogether, these results indicate that CIT-K is a crucial abscission regulator that may promote midbody stability through active RhoA and anillin.

Mammalian SEPT2 Is Required for Scaffolding Nonmuscle Myosin II and Its Kinases

Mammalian septin SEPT2 belongs to a conserved family of filamentous GTPases that are associated with actin stress fibers in interphase cells and the contractile ring in dividing cells. Although SEPT2 is essential for cytokinesis, its role in this process remains undefined. Here, we report that SEPT2 directly binds nonmuscle myosin II (myosin II), and this association is important for fully activating myosin II in interphase and dividing cells. Inhibition of the SEPT2-myosin II interaction in interphase cells results in loss of stress fibers, while in dividing cells this causes instability of the ingressed cleavage furrow and dissociation of the myosin II from the Rho-activated myosin kinases ROCK and citron kinase. We propose that SEPT2-containing filaments provide a molecular platform for myosin II and its kinases to ensure the full activation of myosin II that is necessary for the final stages of cytokinesis.

PtdIns(4,5)P2 Functions at the Cleavage Furrow during Cytokinesis

Phosphoinositides play important roles in regulating the cytoskeleton and vesicle trafficking, potentially important processes at the cleavage furrow. However, it remains unclear which, if any, of the phosphoinositides play a role during cytokinesis. A systematic analysis to determine if any of the phosphoinositides might be present or of functional importance at the cleavage furrow has not been published. Several studies hint at a possible role for one or more phosphoinositides at the cleavage furrow. The best of these are genetic data identifying mutations in phosphoinositide-modifying enzymes (a PtdIns(4)P-5-kinase in S. pombe and a PI-4-kinase in D. melanogaster) that interfere with cytokinesis. The genetic nature of these experiments leaves questions as to how direct may be their contribution to cytokinesis. Here we show that a single phosphoinositide, PtdIns(4,5)P2, specifically accumulates at the furrow. Interference with PtdIns(4,5)P2 interferes with adhesion of the plasma membrane to the contractile ring at the furrow. Finally, four distinct interventions to specifically interfere with PtdIns(4,5)P2 each impair cytokinesis. We conclude that PtdIns(4,5)P2 is present at the cleavage furrow and is required for normal cytokinesis at least in part because of a role in adhesion between the contractile ring and the plasma membrane.