Cofilin 1 induces the epithelial-mesenchymal transition of gastric cancer cells by promoting cytoskeletal rearrangement

A glimpse into cofilin-1 role in cancer therapy: A potential target to improve clinical outcomes?

Cofilin-1 (CFL1) modulates dynamic actin networks by severing and enhancing depolymerization. The upregulation of cofilin-1 expression in several cancer types is associated with tumor progression and metastasis. However, recent discoveries indicated relevant cofilin-1 functions under oxidative stress conditions, interplaying with mitochondrial dynamics, and apoptosis networks. In this scenario, these emerging roles might impact the response to clinical therapy and could be used to enhance treatment efficacy. Here, we highlight new perspectives of cofilin-1 in the therapy resistance context and discussed how cofilin-1 is involved in these events, exploring aspects of its contribution to therapeutic resistance. We also provide an analysis of CFL1 expression in several tumors predicting survival. Therefore, understanding how exactly coflin-1 plays, particularly in therapy resistance, may pave the way to the development of treatment strategies and improvement of patient survival.

Nanomechanical Characterization of Ovarian Cancer Cell Lines as a Marker of Response to 2c Treatment

Epithelial ovarian cancers (EOCs) are a heterogeneous group of tumors with different molecular and clinical features. In past decades, few improvements have been achieved in terms of EOC management and treatment efficacy, such that the 5-year survival rate of patients remained almost unchanged. A better characterization of EOCs' heterogeneity is needed to identify cancer vulnerabilities, stratify patients and adopt proper therapies. The mechanical features of malignant cells are emerging as new biomarkers of cancer invasiveness and drug resistance that can further improve our knowledge of EOC biology and allow the identification of new molecular targets. In this study, we determined the inter and intra-mechanical heterogeneity of eight ovarian cancer cell lines and their association with tumor invasiveness and resistance to an anti-tumoral drug with cytoskeleton depolymerization activity (2c).

Celastrus orbiculatus Thunb. extract inhibits EMT and metastasis of gastric cancer by regulating actin cytoskeleton remodeling

ETHNOPHARMACOLOGICAL RELEVANCE

The traditional Chinese medicine herb Celastrus orbiculatus Thunb. is an important folk medicinal plant in China that has been used as an anti-inflammatory, antitumor, and analgesic in various diseases. Recent years, many studies have reported the significant effects of Celastrus orbiculatus Thunb. extract (COE) on gastric cancer. However, the specific mechanism by which COE regulates gastric cancer cytoskeleton remodeling and thus inhibits EMT has not yet been reported.

AIM OF STUDY

To study the effect and mechanism of COE in inhibiting the epithelial-mesenchymal transition (EMT) and metastasis of gastric cancer cells, laying an experimental foundation for the clinical application and further development of COE.

METHODS

The high-content cell dynamic tracking system was used to continuously track the trajectory of cell movement in real time. Through the high-content data, the average movement distance and movement speed of the cells are calculated. Additionally, the dynamic images of the cell movement in the high-content imaging system are derived to analyze the impact of COE on the movement of gastric cancer cells. Cytoskeleton staining experiment was performed to detect the effect of COE on the assembly of gastric cancer cell cytoskeleton proteins. Western blot was employed to detect the changes of EMT and metastasis-related proteins in the gastric cancer cells treated by COE. The effect of COE on the key regulatory protein Cofilin-1 (CFL1) of cell movement was examined by Western blot and protein degradation experiment. The effect of COE on EMT and metastasis of the gastric cancer cells lacking CFL1 was assessed by a transwell assay. The in vivo inhibitory effect of COE on EMT and metastasis of gastric cancer was determined by the animal living image system. IHC assays were used to detect the levels of EMT-related proteins in COE reversal in vivo.

RESULT

The results showed that the movement distance and average movement speed of gastric cancer cells after COE treatment were significantly lower than those of the control group. Cytoskeleton staining experiments revealed that COE can significantly change the distribution of skeletal proteins in gastric cancer cells. Additionally, COE treatment significantly reduced the expression of Matrix metalloproteinases (MMP-2, MMP-9) and other proteins. Furthermore, COE can significantly accelerate the degradation of CFL1 protein, and both COE treatment and CFL1 deletion can significantly inhibit EMT and metastasis of gastric cancer cells. Lastly, the number of peritoneal metastases of gastric cancer cells was significantly reduced in animals after COE treatment. COE can reverse the levels of EMT-related proteins while reducing the expression levels of CFL1 protein in vivo.

CONCLUSION

COE can significantly inhibit EMT and metastasis of gastric cancer cells in vivo and in vitro. This effect may be achieved by reducing the stability of CFL1 and inhibiting the assembly of actin in gastric cancer cells.

The phosphorylation level of Cofilin-1 is related to the pathological subtypes of gastric cancer

The purpose of the study was to explore the relationship between multiple proteins belonging to the LIMK/Cofilin pathway, including LIMK1, LIMK2, Cofilin-1, and p-Cofilin-1 and clinical features of gastric cancer (GC) patients, including overall survival, TNM stages, and pathological subtypes. The expression of LIMK1, LIMK2, Cofilin-1 and p-Cofilin-1 in the GC tissues and adjacent normal stomach tissues from 141 patients were detected using immunohistochemistry (IHC) staining. Wilcoxon rank-sum test and Spearman rank correlation coefficients were used to measure the relationship between different TNM stages, pathological types, and selected parameters. OS was estimated using the Kaplan-Meier method and survival curves were compared using the log-rank test. Our results showed that, compared to those in the adjacent normal stomach tissues, LIMK1, LIMK2 and Cofilin-1 were up-regulated while p-Cofilin-1 was down-regulated in the GC tissues. LIMK1 level was positively correlated to the TNM stages of GC. According to the published dataset, the expression levels of both LIMK1 and LIMK2 were correlated to the overall survival time of GC patients. The level of Cofilin-1 was significantly different between GCs of different TNM stages. Moreover, most importantly, this is the first study to reveal that the level of Cofilin-1 is higher, and the level of p-Cofilin-1 is lower in the diffuse type of GC compared to that in intestinal type. Taken together, our study demonstrated that multiple factors in LIMK/Cofilin pathway including LIMK1, LIMK2, Cofilin-1, and p-Cofilin-1 were associated with the clinical and pathological features of GC, which is potentially helpful for the diagnosis and treatment of GC.

E2F4-induced AGAP2-AS1 up-regulation accelerates the progression of colorectal cancer via miR-182-5p/CFL1 axis

BACKGROUND

Long non-coding RNAs (lncRNAs) are closely associated with the pathogenesis of numerous diseases including cancers. LncRNA AGAP2 Antisense RNA 1 (AGAP2-AS1) has been found to participate in the tumorigenesis of several kinds of human cancers. Nonetheless, its potential function in colorectal cancer (CRC) was still poorly investigated.

METHODS

The expression level of RNAs or proteins was assessed by RT-qPCR or western blot analysis. Functional experiments were performed to analyze the role of AGAP2-AS1 in CRC in vitro and in vivo. Mechanism investigations were fulfilled to determine the potential mechanism of the molecules.

RESULTS

AGAP2-AS1 expression was significantly elevated in CRC cells and could be transcriptionally activated by E2F Transcription Factor 4 (E2F4). Down-regulated AGAP2-AS1 could weaken CRC cell growth, migration, invasion, and epithelial-mesenchymal transition (EMT). MicroRNA-182-5p (miR-182-5p) was the target downstream molecule of AGAP2-AS1. Furthermore, Cofilin 1 (CFL1) was proved as the target of miR-182-5p. Mechanically, AGAP2-AS1 could boost the CFL1 expression via competitively binding to miR-182-5p in CRC. Importantly, CFL1 restoration could counteract the in vitro and in vivo suppression of depleted AGAP2-AS1 on CRC progression.

CONCLUSION

E2F4-stimulated AGAP2-AS1 aggravated CRC development through regulating miR-182-5p/CFL1 axis, implying that AGAP2-AS1 might become a potent new target for future therapies for CRC.

Multi-Omics Analysis of Glioblastoma and Glioblastoma Cell Line: Molecular Insights Into the Functional Role of GPR56 and TG2 in Mesenchymal Transition

G protein-coupled receptor 56 (GPR56/ADGRG1) is an adhesion GPCR with an essential role in brain development and cancer. Elevated expression of GPR56 was observed in the clinical specimens of Glioblastoma (GBM), a highly invasive primary brain tumor. However, we found the expression to be variable across the specimens, presumably due to the intratumor heterogeneity of GBM. Therefore, we re-examined GPR56 expression in public domain spatial gene expression data and single-cell expression data for GBM, which revealed that GPR56 expression was high in cellular tumors, infiltrating tumor cells, and proliferating cells, low in microvascular proliferation and peri-necrotic areas of the tumor, especially in hypoxic mesenchymal-like cells. To gain a better understanding of the consequences of GPR56 downregulation in tumor cells and other molecular changes associated with it, we generated a sh-RNA-mediated GPR56 knockdown in the GBM cell line U373 and performed transcriptomics, proteomics, and phospho-proteomics analysis. Our analysis revealed enrichment of gene signatures, pathways, and phosphorylation of proteins potentially associated with mesenchymal (MES) transition in the tumor and concurrent increase in cell invasion and migration behavior of the GPR56 knockdown GBM cells. Interestingly, our analysis also showed elevated expression of Transglutaminase 2 (TG2) - a known interactor of GPR56, in the knockdown cells. The inverse expression of GPR56 and TG2 was also observed in intratumoral, spatial gene expression data for GBM and in GBM cell lines cultured in vitro under hypoxic conditions. Integrating all these observations, we propose a putative functional link between the inverse expression of the two proteins, the hypoxic niche and the mesenchymal status in the tumor. Hypoxia-induced downregulation of GPR56 and activation of TG2 may result in a network of molecular events that contribute to the mesenchymal transition of GBM cells, and we propose a putative model to explain this functional and regulatory relationship of the two proteins.

Oral Microbiota-Driven Cell Migration in Carcinogenesis and Metastasis

The oral cavity harbors approximately 1,000 microbial species, and both pathogenic and commensal strains are involved in the development of carcinogenesis by stimulating chronic inflammation, affecting cell proliferation, and inhibiting cell apoptosis. Moreover, some substances produced by oral bacteria can also act in a carcinogenic manner. The link between oral microbiota and chronic inflammation as well as cell proliferation has been well established. Recently, increasing evidence has indicated the association of the oral microbiota with cell migration, which is crucial in regulating devastating diseases such as cancer. For instance, increased cell migration induced the spread of highly malignant cancer cells. Due to advanced technologies, the mechanistic understanding of cell migration in carcinogenesis and cancer metastasis is undergoing rapid progress. Thus, this review addressed the complexities of cell migration in carcinogenesis and cancer metastasis. We also integrate recent findings on the molecular mechanisms by which the oral microbiota regulates cell migration, with emphasis on the effect of the oral microbiota on adhesion, polarization, and guidance. Finally, we also highlight critical techniques, such as intravital microscopy and superresolution microscopy, for studies in this field.

Epigenetic Regulation Mechanisms of the Cofilin-1 Gene in the Development and Differentiation of Bovine Primary Myoblasts

As the quality of beef products has received increasing attention, it is essential to explore the underlying transcriptional and epigenetic mechanisms of meat traits. Our project uses Qinchuan cattle as the research subject. First, we examined the spatiotemporal expression pattern of the CFL1 gene in a panel of fetal bovine, calf, and adult cattle samples. Then, we performed DNA methylation experiments of CFL1 on myogenesis and muscle maturation using the BSP amplification and COBRA sequencing techniques and found that high DNA methylation levels showed low expression levels. Next, we performed an assay between bta-miR-182 and the CFL1 gene and demonstrated that miR-182 could promote bovine primary myoblast differentiation by negatively regulated the expression of CFL1. Finally, we constructed an adenovirus overexpression and interference vector and found that CFL1 could suppress the differentiation of bovine primary myoblasts. In summary, our experiment comprehensively analyzes the epigenetic regulation mechanisms of the CFL1 gene in the development and differentiation of bovine primary myoblasts. This has far-reaching significance for improving the meat production and meat quality of Qinchuan cattle. This can provide reliable data support and a theoretical research basis for the rapid and efficient breeding selection of local yellow cattle and the genetic improvement of meat quality.

New Insights into the Roles of lncRNAs as Modulators of Cytoskeleton Architecture and Their Implications in Cellular Homeostasis and in Tumorigenesis

The importance of the cytoskeleton not only in cell architecture but also as a pivotal element in the transduction of signals that mediate multiple biological processes has recently been highlighted. Broadly, the cytoskeleton consists of three types of structural proteins: (1) actin filaments, involved in establishing and maintaining cell shape and movement; (2) microtubules, necessary to support the different organelles and distribution of chromosomes during cell cycle; and (3) intermediate filaments, which have a mainly structural function showing specificity for the cell type where they are expressed. Interaction between these protein structures is essential for the cytoskeletal mesh to be functional. Furthermore, the cytoskeleton is subject to intense spatio-temporal regulation mediated by the assembly and disassembly of its components. Loss of cytoskeleton homeostasis and integrity of cell focal adhesion are hallmarks of several cancer types. Recently, many reports have pointed out that lncRNAs could be critical mediators in cellular homeostasis controlling dynamic structure and stability of the network formed by cytoskeletal structures, specifically in different types of carcinomas. In this review, we summarize current information available about the roles of lncRNAs as modulators of actin dependent cytoskeleton and their impact on cancer pathogenesis. Finally, we explore other examples of cytoskeletal lncRNAs currently unrelated to tumorigenesis, to illustrate knowledge about them.

Epithelial plasticity in COPD results in cellular unjamming due to an increase in polymerized actin

The airway epithelium is subjected to insults such as cigarette smoke (CS), a primary cause of chronic obstructive pulmonary disease (COPD) and serves as an excellent model to study cell plasticity. Here, we show that both CS-exposed and COPD-patient derived epithelia (CHBE) display quantitative evidence of cellular plasticity, with loss of specialized apical features and a transcriptional profile suggestive of partial epithelial-to-mesenchymal transition (pEMT), albeit with distinct cell motion indicative of cellular unjamming. These injured/diseased cells have an increased fraction of polymerized actin, due to loss of the actin-severing protein cofilin-1. We observed that decreasing polymerized actin restores the jammed state in both CHBE and CS-exposed epithelia, indicating that the fraction of polymerized actin is critical in unjamming the epithelia. Our kinetic energy spectral analysis suggests that loss of cofilin-1 results in unjamming, similar to that seen with both CS exposure and in CHBE cells. The findings suggest that in response to chronic injury, although epithelial cells display evidence of pEMT, their movement is more consistent with cellular unjamming. Inhibitors of actin polymerization rectify the unjamming features of the monolayer. This article has an associated First Person interview with the first author of the paper.

The Pseudomonas aeruginosa Secreted Protein PA3611 Promotes Bronchial Epithelial Cell Epithelial-Mesenchymal Transition via Integrin αvβ6-Mediated TGF-β1-Induced p38/NF-κB Pathway Activation

Pseudomonas aeruginosa (PA) is an important pathogen that has been proven to colonize and cause infection in the respiratory tract of patients with structural lung diseases and to lead to bronchial fibrosis. The development of pulmonary fibrosis is a complication of PA colonization of the airway, resulting from repeated infection, damage and repair of the epithelium. Bronchial epithelial cell epithelial-mesenchymal transition (EMT) plays a vital role in bronchial fibrosis. To date, research on bronchial epithelial cell EMT caused by PA-secreted virulence factors has not been reported. Here, we found that PA3611 protein stimulation induced bronchial epithelial cell EMT with mesenchymal cell marker upregulation and epithelial cell marker downregulation. Moreover, integrin αvβ6 expression and TGF-β1 secretion were markedly increased, and p38 MAPK phosphorylation and NF-κB p65 subunit phosphorylation were markedly enhanced. Further research revealed that PA3611 promoted EMT via integrin αvβ6-mediated TGF-β1-induced p38/NF-κB pathway activation. The function of PA3611 was also verified in PA-infected rats, and the results showed that ΔPA3611 reduced lung inflammation and EMT. Overall, our results revealed that PA3611 promoted EMT via integrin αvβ6-mediated TGF-β1-induced p38/NF-κB pathway activation, suggesting that PA3611 acts as a crucial virulence factor in bronchial epithelial cell EMT and is a potential target for the clinical treatment of bronchial EMT and fibrosis caused by chronic PA infection.

Betulonic Acid, as One of the Active Components of the Celastrus orbiculatus Extract, Inhibits the Invasion and Metastasis of Gastric Cancer Cells by Mediating Cytoskeleton Rearrangement In Vitro

Gastric cancer is a type of malignant tumor that seriously threatens human life and health. Invasion and metastasis present difficulties in the treatment of gastric cancer, and the remodeling of the tumor cytoskeleton plays an important role in mediating the ability of tumor cells to achieve invasion and metastasis. Previous experimental results suggest that Celastrus orbiculatus extract can regulate cytoskeletal remodeling in gastric cancer, but the active component has not been determined. Betulonic acid, as an effective component of COE, inhibits the invasion and metastasis of gastric cancer cells by regulating cytoskeletal remodeling in vitro; its specific mechanisms have been studied here. After betulonic acid was dissolved, it was diluted to various working concentrations in RPMI-1640 medium and added to AGS, HGC-27 and GES-1 cell lines. Cell viability was assessed by CCK-8 and colony formation assays. Cytoskeleton staining was used to detect changes in cytoskeleton morphology. Functional assays including wound healing assays and transwell assays were used to detect the invasion and migration of cells. The effect of betulonic acid on cell invasion and migration was clearly and precisely observed by high-content imaging technology. Western blotting was used to detect the regulation of matrix metalloproteinase-related proteins and epithelial–mesenchymal transformation-related proteins. We found that betulonic acid inhibited the migration and invasion of gastric cancer cells. Therefore, betulonic acid inhibits the invasion and metastasis of gastric cancer cells by mediating cytoskeletal remodeling and regulating epithelial mesenchymal transformation.

The Ethyl Acetate Extract From Celastrus orbiculatus Promotes Apoptosis of Gastric Cancer Cells Through Mitochondria Regulation by PHB

Objective: To investigate the effect of ethyl acetate extract from Celastrus orbiculatus (COE) on gastric cancer cell apoptosis and reveal its underlying molecular mechanism. In addition, it was aimed to stablish a theoretical basis for the clinical application of Celastrus orbiculatus in the gastric cancer treatment. Material and Methods: Western blot and RT-qPCR were used to detect mRNA and protein expression of PHB in gastric cancer and adjacent tissues. MTT method was used to detect the COE effect on the proliferation of AGS cells and to determine the 50% inhibitory concentration COE on these cells. COE effect on AGS apoptosis was evaluated by flow cytometry. Changes in apoptosis-related proteins expression in AGS cells were detected by western blot and changes in mitochondrial membrane potential were detected by JC-1 fluorescence staining. PHB expression was knocked down in AGS cells by lentiviral-mediated RNA interference. The COE antitumor effect was assessed in vivo using a subcutaneous transplantation tumor model in nude mice and in vivo fluorescence tracing technique in small animals. Results: The clinical samples analysis results showed that the PHB expression in gastric cancer samples was significantly higher than in corresponding adjacent tissues. MTT results showed that the AGS cell proliferation was significantly inhibited. RT-qPCR and western blot results showed that COE can significantly inhibit the PHB mRNA and protein expression, respectively. Flow cytometry analysis showed that COE was able to significantly promote AGS cell apoptosis. Western blot results also indicated that apoptosis-related protein expression changed significantly; BCL-2 expression significantly reduced while the Caspase-3 and Bax expression significantly increased after COE treatment. JC-1 fluorescence staining results showed that COE changed the mitochondrial membrane potential and activated the mitochondrial apoptosis pathway. Furthermore, in vivo experiments results demonstrated that the growth of subcutaneous transplanted tumor was significantly inhibited by the PHB knockdown and by the COE intragastric administration. Conclusion: COE can significantly promote apoptosis of human gastric cancer cells, which can be achieved by inhibiting PHB expression, thus altering the structure and function of mitochondria and activating the mitochondria apoptosis pathway. The antitumor effect of COE has also been proved in vivo.

Actin Cytoskeleton and Regulation of TGFβ Signaling: Exploring Their Links

Human tissues, to maintain their architecture and function, respond to injuries by activating intricate biochemical and physical mechanisms that regulates intercellular communication crucial in maintaining tissue homeostasis. Coordination of the communication occurs through the activity of different actin cytoskeletal regulators, physically connected to extracellular matrix through integrins, generating a platform of biochemical and biomechanical signaling that is deregulated in cancer. Among the major pathways, a controller of cellular functions is the cytokine transforming growth factor β (TGFβ), which remains a complex and central signaling network still to be interpreted and explained in cancer progression. Here, we discuss the link between actin dynamics and TGFβ signaling with the aim of exploring their aberrant interaction in cancer.

Unraveling the Molecular Tumor-Promoting Regulation of Cofilin-1 in Pancreatic Cancer

Cofilin-1 (CFL1) overexpression in pancreatic cancer correlates with high invasiveness and shorter survival. Besides a well-documented role in actin remodeling, additional cellular functions of CFL1 remain poorly understood. Here, we unraveled molecular tumor-promoting functions of CFL1 in pancreatic cancer. For this purpose, we first show that a knockdown of CFL1 results in reduced growth and proliferation rates in vitro and in vivo, while apoptosis is not induced. By mechanistic modeling we were able to predict the underlying regulation. Model simulations indicate that an imbalance in actin remodeling induces overexpression and activation of CFL1 by acting on transcription factor 7-like 2 (TCF7L2) and aurora kinase A (AURKA). Moreover, we could predict that CFL1 impacts proliferation and apoptosis via the signal transducer and activator of transcription 3 (STAT3). These initial model-based regulations could be substantiated by studying protein levels in pancreatic cancer cell lines and human datasets. Finally, we identified the surface protein CD44 as a promising therapeutic target for pancreatic cancer patients with high CFL1 expression.

Cofilin-1, LIMK1 and SSH1 are differentially expressed in locally advanced colorectal cancer and according to consensus molecular subtypes

Background

Colorectal cancer (CRC) is among the deadliest cancers, wherein early dissemination of tumor cells, and consequently, metastasis formation, are the main causes of mortality and poor prognosis. Cofilin-1 (CFL-1) and its modulators, LIMK1/SSH1, play key roles in mediating the invasiveness by driving actin cytoskeleton reorganization in various cancer types. However, their clinical significance and prognostic value in CRC has not been fully explored. Here, we evaluated the clinical contribution of these actin regulators according to TNM and consensus molecular subtypes (CMSs) classification.

Methods

CFL-1, LIMK1 and SSH1 mRNA/protein levels were assessed by real-time PCR and immunohistochemical analyses using normal adjacent and tumor tissues obtained from a clinical cohort of CRC patients. The expression levels of these proteins were associated with clinicopathological features by using the chi square test. In addition, using RNA-Seq data of CRC patients from The Cancer Genome Atlas (TCGA) database, we determine how these actin regulators are expressed and distributed according to TNM and CMSs classification. Based on gene expression profiling, Kaplan–Meier survival analysis was used to evaluated overall survival.

Results

Bioinformatic analysis revealed that LIMK1 expression was upregulated in all tumor stages. Patients with high levels of LIMK1 demonstrated significantly lower overall survival rates and exhibited greater lymph node metastatic potential in a clinical cohort. In contrast, CFL-1 and SSH1 have expression downregulated in all tumor stages. However, immunohistochemical analyses showed that patients with high protein levels of CFL-1 and SSH1 exhibited greater lymph node metastatic potential and greater depth of local invasion. In addition, using the CMSs classification to evaluate different biological phenotypes of CRC, we observed that LIMK1 and SSH1 genes are upregulated in immune (CMS1) and mesenchymal (CMS4) subtypes. However, patients with high levels of LIMK1 also demonstrated significantly lower overall survival rates in canonical (CMS2), and metabolic (CMS3) subtypes.

Conclusions

We demonstrated that CFL-1 and its modulators, LIMK1/SSH1, are differentially expressed and associated with lymph node metastasis in CRC. Finally, this expression profile may be useful to predict patients with aggressive signatures, particularly, the immune and mesenchymal subtypes of CRC.

Involvement of Actin and Actin-Binding Proteins in Carcinogenesis

The actin cytoskeleton plays a crucial role in many cellular processes while its reorganization is important in maintaining cell homeostasis. However, in the case of cancer cells, actin and ABPs (actin-binding proteins) are involved in all stages of carcinogenesis. Literature has reported that ABPs such as SATB1 (special AT-rich binding protein 1), WASP (Wiskott-Aldrich syndrome protein), nesprin, and villin take part in the initial step of carcinogenesis by regulating oncogene expression. Additionally, changes in actin localization promote cell proliferation by inhibiting apoptosis (SATB1). In turn, migration and invasion of cancer cells are based on the formation of actin-rich protrusions (Arp2/3 complex, filamin A, fascin, α-actinin, and cofilin). Importantly, more and more scientists suggest that microfilaments together with the associated proteins mediate tumor vascularization. Hence, the presented article aims to summarize literature reports in the context of the potential role of actin and ABPs in all steps of carcinogenesis.

Role of SSH1 in colorectal cancer prognosis and tumor progression

BACKGROUND AND AIM

Slingshot 1 protein (SSH1) plays a critical role in cytoskeleton dynamic regulation. Increasing evidence suggest that SSH1 expression is upregulated in several cancers and relates to tumor progression and drug resistance. Here, we evaluated the role of SSH1 in colorectal cancer (CRC) development and its prognostic value in patients with CRC.

METHODS

SSH1 expression was examined by quantitative real-time polymerase chain reaction, western blot analysis, or immunohistochemistry. The association between SSH1 expression and clinical characteristics and prognosis was evaluated. Stable SSH1 knockdown cells were used for in vitro assays and xenograft models. Correlation between SSH1 expression and epithelial-mesenchymal transition (EMT) was analyzed by western blot and online data analysis.

RESULTS

SSH1 expression was upregulated in cancer tissue compared with paired non-cancerous tissue in patients with CRC. SSH1 expression level in CRC tissue was associated with tumor stage, lymph node metastasis, and correlated with poor prognosis as indicated by univariate and multivariate analyses. In vitro, loss of SSH1 impaired colony formation, migration, and invasion of CRC cells. In vivo data suggest that SSH1 could promote the progression and metastasis of CRC. Interestingly, E-cadherin, ZEB1, and Snail, which are markers of EMT, had a significant expression correlation with SSH1.

CONCLUSIONS

SSH1 expression is associated with CRC progression and predicts poor prognosis. SSH1 may promote CRC tumor progression by regulating EMT.

The polymorphism of bovine Cofilin-1 gene sequence variants and association analysis with growth traits in Qinchuan cattle

In our study, four single nucleotide polymorphisms (SNPs) were identified in exon 2 of cofilin-1 (CFL1) gene in 488 Chinese Qinchuan (QC) cattle, which included two missense mutations T 2084G and G 2107C, two synonymous mutations T 2052C and T 2169C. Further, we evaluated haplotype frequency and linkage disequilibrium (LD) coefficient of four SNPs. At SNP T 2052C, G 2107C and T 2169C, the QC cattle population belonged to intermediate genetic diversity (0.25 < PIC-value < 0.5), whereas SNP T-2084G belonged to low polymorphism (PIC-value < 0.25). Haplotype analysis showed that 6 different haplotypes (frequency > 0.03). LD analysis showed that SNP G 2107C and T 2169C, SNP G 2107C and T 2084G were high LD, respectively (r² > 0.33). Association analysis indicated that SNP T 2052C was significantly associated with body length, chest breadth, chest depth and body mass in the QC population (p < 0.01 or p < 0.05). SNP G 2107C was significantly associated with rump length (p < 0.05). SNP T 2169C was significantly associated with chest breadth and chest depth (p < .01 or p < .05). The results of our study suggest that the CFL1 gene may be a strong candidate gene that affects growth traits in the QC cattle breeding program.

Role of extra cellular proteins in gastric cancer progression and metastasis: an update

Background

Gastric cancer (GC) is one of the most common cancers in the world with a high ratio of mortality. Regarding the late diagnosis, there is a high ratio of distant metastasis among GC cases. Despite the recent progresses in therapeutic modalities, there is not still an efficient therapeutic method to increase survival rate of metastatic GC cases.

Main body

Apart from the various intracellular signaling pathways which are involved in tumor cell migration and metastasis, the local microenvironment is also a critical regulator of tumor cell migration. Indeed, the intracellular signaling pathways also exert their final metastatic roles through regulation of extra cellular matrix (ECM). Therefore, it is required to assess the role of extra cellular components in biology of GC.

Conclusion

In the present review, we summarize 48 of the significant ECM components including 17 ECM modifying enzymes, seven extracellular angiogenic factors, 13 cell adhesion and cytoskeletal organizers, seven matricellular proteins and growth factors, and four proteoglycans and extra cellular glycoproteins. This review paves the way of determination of a specific extra cellular diagnostic and prognostic panel marker for the GC patients.

Overexpression of CFL1 in gastric cancer and the effects of its silencing by siRNA with a nanoparticle delivery system in the gastric cancer cell line

Gastric adenocarcinoma, like other cancers, is a multifactorial genetic disease, and metastasis of cancer cells is one of the main features of this illness. The expression levels of the CFL1 gene have been modulated in this pathway. Using small interfering RNA (siRNA) in the treatment of gastric cancer is considered a hopeful gene therapeutic approach. The present study reported the level of CFL1 genes between tumor and margin and healthy tissue of gastric cancer. Also, the features of a cationic nanoparticle with a polymer coating containing polyacrylic acid and polyethyleneimine that were used in the delivery of CFL1 siRNA, were shown. Then the cytotoxicity, cellular uptake, and gene silencing efficiency of this nanoparticle were evaluated with CFL1siRNA.

METHOD

In this study, the CFL1 gene expression was measured in 40 gastric adenocarcinoma, marginal and 15 healthy biopsy samples by a real-time polymerase chain reaction. Physicochemical characteristics, apoptosis, and inhibition of migration of the delivery of CFL1 siRNA by nanoparticle and lipofectamine were investigated in gastric cancer cells.

RESULT

The CFL1 expression was remarkably increased in gastric cancer tissues in comparison with the marginal samples and normal tissues (p < .05) and the biomarker index for CFL1 was obtained as 0.94, then this gene can be probably used as a biomarker for gastric cancer. After treatment of the AGS cell line by CFL1 siRNA, the CFL1 expression level of mRNA and migration in AGS cells were remarkably suppressed after transfection. Furthermore, the amount of apoptosis increased (p < .05).

CONCLUSION

Our results demonstrated that CFL1 downregulation in AGS cells can interdict cell migration. Finally, our outcomes propose that CFL1 can function as an oncogenic gene in gastric cancer and would be considered as a potential purpose of gene therapy for gastric cancer treatment.

Cortactin: A Major Cellular Target of the Gastric Carcinogen Helicobacter pylori

Cortactin is an actin binding protein and actin nucleation promoting factor regulating cytoskeletal rearrangements in nearly all eukaryotic cell types. From this perspective, cortactin poses an attractive target for pathogens to manipulate a given host cell to their own benefit. One of the pathogens following this strategy is Helicobacter pylori, which can cause a variety of gastric diseases and has been shown to be the major risk factor for the onset of gastric cancer. During infection of gastric epithelial cells, H. pylori hijacks the cellular kinase signaling pathways, leading to the disruption of key cell functions. Specifically, by overruling the phosphorylation status of cortactin, H. pylori alternates the activity of molecular interaction partners of this important protein, thereby manipulating the performance of actin-cytoskeletal rearrangements and cell movement. In addition, H. pylori utilizes a unique mechanism to activate focal adhesion kinase, which subsequently prevents host epithelial cells from extensive lifting from the extracellular matrix in order to achieve chronic infection in the human stomach.

Repression of metastasis-associated protein 2 for inhibiting metastasis of human oral cancer cells by promoting the p-cofilin-1/ LC3-II expression

BACKGROUND

The overexpression of metastasis-associated protein 2 (MTA2) contributes to human tumor progression and metastasis in various tumor cells. However, the role of MTA2 in human oral cancer progression remains unknown.

MATERIALS AND METHODS

MTA2 expression in human oral tumor tissues and cell lines was measured by immunohistochemistry and Western blotting. Cell proliferation and cell cycle were analyzed using MTT assay and flow cytometry. The effects of MTA2 on oral cell migration and invasion were investigated using migration and invasion assays. The expression of MTA2, p-cofilin-1, and MTA2-induced LC3-II levels were measured using Western blotting and an immunofluorescence assay.

RESULTS

Based on the human oral cancer tissue array and TCGA database, we found that MTA2 was increased in oral cancer tissues than in non-tumor oral tissues (P < .01). Moreover, MTA2 is significantly associated with tumor grade (P < .01) and the overall survival rate of patients with grade III tumor (P < .05). MTA2 expression in oral cancer cells was markedly higher than that in normal oral cells. Cell proliferation and cell cycle were not significantly changed in the cells inhibited by MTA2. MTA2 knockdown can inhibit cell migration and invasion of human oral cancer cells. Furthermore, we suggest that MTA2 inhibition enhances p-cofilin and LC3-II expression, and the knockdown of LC3-II expression in cells inhibited by MTA2 had the opposite effect.

CONCLUSION

These results indicate that MTA2 may serve as a candidate prognostic biomarker and that targeting autophagy is a potential therapeutic strategy for treating human oral cancer.

Proteomic Investigation of Malignant Major Salivary Gland Tumors

The purpose of this study was to define the proteome profile of fine needle aspiration (FNA) samples of malignant major salivary gland tumors (MSGT) compared to benign counterparts, and to evaluate potential clinical correlations and future applications. Patients affected by MSGT (n = 20), pleomorphic adenoma (PA) (n = 37) and Warthin's tumor (WT) (n = 14) were enrolled. Demographic, clinical and histopathological data were registered for all patients. FNA samples were processed to obtain the protein extracts. Protein separation was obtained by two-dimensional electrophoresis (2-DE) and proteins were identified by mass spectrometry. Western blot analysis was performed to validate the 2-DE results. Statistical differences between groups were calculated by the Mann-Whitney U test for non-normal data. Spearman's rank correlation coefficient was calculated to evaluate correlations among suggested protein biomarkers and clinical parameters. Twelve and 27 differentially expressed spots were found for MSGT versus PA and MSGT versus WT, respectively. Among these, annexin-5, cofilin-1, peptidyl-prolyl-cis-trans-isomerase-A and F-actin-capping-alpha-1 were able to differentiate MSGT from PA, WT, and healthy samples. Moreover, STRING analysis suggested cofilin-1 as a key node of protein interactions. Some of the overexpressed proteins are related to some clinical factors of our cohort, such as survival and outcome. Our results suggest potential protein biomarkers of MSGT, which could allow for more appropriate treatment plans, as well as shedding light on the molecular pathways involved.

Suppressing serum response factor inhibits invasion in cervical cancer cell lines via regulating Egr‑1 and epithelial-mesenchymal transition

Serum response factor (SRF) is a transcription factor that has important roles in tumor progression. However, its role in cervical cancer cell proliferation and invasion remains unclear. The present study revealed that SRF silencing constrained cervical cancer cell proliferation and invasion via controlling early growth response‑1 (Egr‑1). The results demonstrated that SRF was significantly increased in cervical cancer tissues and cell lines, compared with normal. Suppressing SRF, by using a loss‑of‑function experiment, constrained cervical cancer cell proliferation, invasion, and epithelial‑mesenchymal transition. Furthermore, SRF knockdown significantly downregulated Egr‑1 expression in cervical cancer cell lines, and overexpression of Egr‑1 reversed the effect of SRF on cell proliferation, invasion, and epithelial‑mesenchymal transition. Therefore, SRF may control cell proliferation and invasion by regulating Egr‑1 in cervical cancer.

Promoter Methylation-Regulated miR-145-5p Inhibits Laryngeal Squamous Cell Carcinoma Progression by Targeting FSCN1

Laryngeal squamous cell carcinoma (LSCC) is a common form of head and neck cancer with poor prognosis. However, the mechanism underlying the pathogenesis of LSCC remains unclear. Here, we demonstrated increased expression of fascin actin-bundling protein 1 (FSCN1) and decreased expression of microRNA-145-5p (miR-145-5p) in a clinical cohort of LSCC. Luciferase assay revealed that miR-145-5p is a negative regulator of FSCN1. Importantly, low miR-145-5p expression was correlated with TNM (tumor, node, metastasis) status and metastasis. Moreover, cases with low miR-145-5p/high FSCN1 expression showed poor prognosis, and these characteristics together served as independent prognostic indicators of survival. Gain- and loss-of-function studies showed that miR-145-5p overexpression or FSCN1 knockdown inhibited LSCC migration, invasion, and growth by suppressing the epithelial-mesenchymal transition along with inducing cell-cycle arrest and apoptosis. Additionally, hypermethylation of the miR-145-5p promoter suggested that repression of miR-145-5p arises through epigenetic inactivation. LSCC tumor growth in vivo could be inhibited by using miR-145-5p agomir or FSCN1 small interfering RNA (siRNA), which highlights the potential for clinical translation. Collectively, our findings indicate that miR-145-5p plays critical roles in inhibiting the progression of LSCC by suppressing FSCN1. Both miR-145-5p and FSCN1 are important potential prognostic markers and therapeutic targets for LSCC.

Changes in Vasodilator-Stimulated Phosphoprotein Phosphorylation, Profilin-1, and Cofilin-1 in Accreta and Protection by DHA

Accreta and gestational trophoblastic disease (ie, choriocarcinoma) are placental pathologies characterized by hyperproliferative and invasive trophoblasts. Cellular proliferation, migration, and invasion are heavily controlled by actin-binding protein (ABP)-mediated actin dynamics. The ABP vasodilator-stimulated phosphoprotein (VASP) carries key regulatory role. Profilin-1, cofilin-1, and VASP phosphorylated at Ser157 (pVASP-S157) and Ser239 (pVASP-S239) are ABPs that regulate actin polymerization and stabilization and facilitate cell metastases. Docosahexaenoic acid (DHA) inhibits cancer cell migration and proliferation. We hypothesized that analogous to malignant cells, ABPs regulate these processes in extravillous trophoblasts (EVTs), which exhibit aberrant expression in placenta accreta. Placental-myometrial junction biopsies of histologically confirmed placenta accreta had significantly increased immunostaining levels of cofilin-1, VASP, pVASP-S239, and F-actin. Treatment of choriocarcinoma-derived trophoblast (BeWo) cells with DHA (30 µM) for 24 hours significantly suppressed proliferation, migration, and pVASP-S239 levels and altered protein profiles consistent with increased apoptosis. We concluded that in accreta changes in the ABP expression profile were a response to restore homeostasis by counteracting the hyperproliferative and invasive phenotype of the EVT. The observed association between VASP phosphorylation, apoptosis, and trophoblast proliferation and migration suggest that DHA may offer a therapeutic solution for conditions where EVT is hyperinvasive.

WDR1 Promotes Cell Growth and Migration and Contributes to Malignant Phenotypes of Non-small Cell Lung Cancer through ADF/cofilin-mediated Actin Dynamics

The characteristic of carcinoma is cell migration and invasion, which involve in strong actin dynamics. Regulations of actin dynamics have been implicated in cancer cell migration and tumor progression. WDR1 (WD-repeat domain 1) is a major cofactor of the actin depolymerizing factor (ADF)/cofilin, strongly accelerating ADF/cofilin-mediated actin disassembly. The role of WDR1 in non-small cell lung cancer (NSCLC) progression has been unknown. Here, we show that the expression levels of WDR1 are increased in human NSCLC tissues compared with adjacent non-tumor tissues, and high WDR1 level correlates with poor prognosis in NSCLC patients. Knockdown of WDR1 in NSCLC cells significantly inhibits cell migration, invasion, EMT process and tumor cell growth in vitro and in vivo. Otherwise, overexpression of WDR1 promotes NSCLC cell proliferation and migration. Mechanically, our data suggested WDR1 regulated tumor cells proliferation and migration might through actin cytoskeleton-mediated regulation of YAP, and we demonstrated that WDR1 contributes to NSCLC progression through ADF/cofilin-mediated actin disassembly. Our findings implicate that the ADF/cofilin-WDR1-actin axis as an activator of malignant phenotype that will be a promising therapeutic target in lung cancer.

LIMK/cofilin pathway and Slingshot are implicated in human colorectal cancer progression and chemoresistance

Cofilin phospho-regulation is important for actin filament turnover and is implicated in cancer. Phosphorylation of cofilin is mediated by LIM kinases (LIMKs) and dephosphorylation by Slingshot phosphatases (SSH). LIMKs and SSH promote cancer cell invasion and metastasis and represent novel anti-cancer targets. However, little is known regarding LIMK/cofilin and SSH in human colorectal cancer (CRC). In this study, we aimed to address their expression and significance in human CRC. We evaluated expression of non-phosphorylated (active) and phosphorylated cofilin, LIMK1, LIMK2, and SSH1 by immunohistochemistry in 143 human CRC samples in relation to clinicopathologic parameters, response of metastatic disease to chemotherapy, and epithelial-mesenchymal transition (EMT) markers β-catenin, E-cadherin, and ZEB. We show that active cofilin, LIMK1, LIMK2, and SSH1 are overexpressed in human CRC and are associated with tumor progression parameters. SSH1 is an independent predictor of lymph node metastasis by multivariate analysis. LIMK1 and SSH1 expression is also higher in non-responders to chemotherapy, and SSH1 is shown by multivariate analysis to independently predict response of metastatic disease to chemotherapy. Active cofilin, LIMK1, LIMK2, and SSH1 also correlated with the EMT markers examined. In addition, immunofluorescence analysis showed increased expression of active cofilin, LIMK1, LIMK2, and SSH1 in HT29 colon cancer cells resistant to 5-fluorouracil compared to parental HT29 cells. Our results suggest that F-actin regulators LIMK/cofilin pathway and SSH1 are associated with CRC progression and chemoresistance representing promising tumor biomarkers and therapeutic targets in CRC.

The Role of Actin Dynamics and Actin-Binding Proteins Expression in Epithelial-to-Mesenchymal Transition and Its Association with Cancer Progression and Evaluation of Possible Therapeutic Targets

Metastasis causes death of 90% of cancer patients, so it is the most significant issue associated with cancer disease. Thus, it is no surprise that many researchers are trying to develop drugs targeting or preventing them. The secondary tumour site formation is closely related to phenomena like epithelial-to-mesenchymal and its reverse, mesenchymal-to-epithelial transition. The change of the cells' phenotype to mesenchymal involves the acquisition of migratory potential. Cancer cells movement is possible due to the development of invasive structures like invadopodia, lamellipodia, and filopodia. These changes are dependent on the reorganization of the actin cytoskeleton. In turn, the polymerization and depolymerization of actin are controlled by actin-binding proteins. In many tumour cells, the actin and actin-associated proteins are accumulated in the cell nucleus, suggesting that it may also affect the progression of cancer by regulating gene expression. Once the cancer cell reaches a new habitat it again acquires epithelial features and thus proliferative activity. Targeting of epithelial-to-mesenchymal or/and mesenchymal-to-epithelial transitions through regulation of their main components expression may be a potential solution to the problem of metastasis. This work focuses on the role of these processes in tumour progression and the assessment of therapeutic potential of agents targeting them.

Celastrus orbiculatus extract suppresses the epithelial-mesenchymal transition by mediating cytoskeleton rearrangement via inhibition of the Cofilin 1 signaling pathway in human gastric cancer

Celastrus orbiculatus is a traditional medicinal plant used in the anti-inflammatory and analgesic treatment of various diseases. A previous study demonstrated that ethyl acetate extract of C. orbiculatus (COE) exhibited significant antitumor effects. However, studies concerning the effects and mechanism of COE in terms of suppressing the epithelial-mesenchymal transition (EMT) in human gastric adenocarcinoma cells have not been performed at present. The present study hypothesized that COE may inhibit EMT in gastric adenocarcinoma cells by regulating cell cytoskeleton rearrangement. The effect of COE on the viability of AGS cells was detected by MTT assay. An EMT model was induced by transforming growth factor-β1. Cell cytoskeleton staining, laser scanning confocal microscopy and electronic microscopy were used to detect the changes in cell morphology and microstructure of gastric adenocarcinoma cells prior and subsequent to COE treatment. Invasion and migration assays were used to observe the effect of COE on the metastatic ability of AGS cells in vitro. The effect of COE on the expression of Cofilin 1 and EMT biomarkers, including Epithelial-cadherin, Neural-cadherin, Vimentin and matrix metalloproteinases, was examined by western blotting in AGS cells. The correlation between Cofilin 1 and EMT was investigated with immunofluorescence and cytoskeleton staining methods. The results demonstrated that COE may significantly inhibit the process of EMT in AGS cells, and that this was concentration-dependent. In addition, COE significantly downregulated the level of Cofilin 1 in a concentration-dependent manner. In conclusion, these results suggested that Cofilin 1 was directly involved in the process of EMT in AGS cells, and that it served an important function. COE may significantly inhibit EMT in AGS cells, potentially by inhibiting the activation of the Cofilin 1 signaling pathway. The present study may provide a basis for the development of novel anticancer drugs and the development of novel therapeutic strategies, targeting Cofilin 1 protein.