Fascins, and their roles in cell structure and function

The mechanism underlying fascin-mediated bundling of actin filaments unveiled by cryo-electron tomography

Fascins are crucial actin-binding proteins linked to carcinomas, such as cancer metastasis. Fascins crosslink unipolar actin filaments into linear and rigid parallel bundles, which play essential roles in the formation of filopodia, stereocilia and other membrane protrusions. However, the mechanism of how fascin bundles actin filaments has remained elusive. Here, we studied the organization of reconstituted fascin-actin bundles by cryo-electron tomography and determined the structure of the fascin-actin complex at 9Å resolution by subtomogram averaging. Consistent with earlier findings, fascin molecules decorate adjacent actin filaments, positioned at regular intervals corresponding to the half-pitch of actin filaments. The fascin-actin complex structure allows us to verify the binding orientation of fascin between the two actin filaments. Fitting of the previously solved fascin crystal structure facilitates the analysis of the interaction surfaces. Our structural models serve as a blueprint to understand the detailed interactions between fascin and actins and provide new insights for the development of drugs targeting fascin- proteins.

A Critical Role for the Fascin Family of Actin Bundling Proteins in Axon Development, Brain Wiring and Function

Actin-based cell motility drives many neurodevelopmental events including guided axonal growth. Fascin is a major family of F-actin bundling proteins, but its role in axon development in vivo and brain wiring remains unclear. Here, we report that fascin is required for axon development, brain wiring and function. We show that fascin is enriched in the motile filopodia of axonal growth cones and its inhibition impairs axonal extension and branching of hippocampal neurons in culture. We next provide evidence that fascin is essential for axon development and brain wiring in vivo using Drosophila melanogaster as a model. Drosophila expresses a single ortholog of mammalian fascin called Singed (SN), which is highly expressed in the mushroom body (MB) of the central nervous system. We observe that loss of SN results in drastic MB disruption, highlighted by α- and β-lobe defects that are consistent with altered axonal guidance. SN-null flies also exhibit defective sensorimotor behaviors as assessed by the negative geotaxis assay. MB- specific expression of SN in SN-null flies rescues MB structure and sensorimotor deficits, indicating that SN functions autonomously in MB neurons. Together, our data from primary neuronal culture and in vivo models highlight a critical role for fascin in brain development and function.

Highlights

Fascin regulates axonal growth and branching of hippocampal neurons in culture.Singed, Drosophila fascin, is enriched specifically in mushroom body (MB) axons.Singed loss causes axon guidance defects and sensorimotor issues in flies.MB-specific Singed re-expression rescues MB structure and behavior in flies.

Comparison of Fascin Expression in Oral Verrucous Carcinoma and Oral Squamous Cell Carcinoma

Introduction: One of the diagnostic problems of pathology is to differentiate between oral verrucous carcinoma (OVC) and oral squamous cell carcinoma (OSCC). Fascin increases the invasion of normal and neoplastic cells by stabilizing cytoplasmic filamentous actin. The present study aimed to investigate the expression of fascin in OSCC and OVC. Methods: This descriptive-analytical cross-sectional was conducted on 25 blocks of OSCC, 22 blocks of OVC, and 10 blocks of healthy mucosa as a control group. After immunohistochemical staining, samples were observed by two maxillofacial pathologists simultaneously, and the percentage of stained cells, intensity of staining, and the location of stained cells were obtained. Results: There was no significant difference in the gender (p=0.123) and age (p=0.276) distribution of participants in the groups. There was a significant difference in the distribution of the involved area in the patients of the studied groups (p < 0.001). There was a significant difference in the intensity of staining and the percentage of stained cells between the studied groups (p < 0.001). Conclusions: The percentage and intensity of staining were higher in the OSCC, OVC and, control groups, respectively. It seems that Fascin expression has an important role in predicting OVC and OSCC.

The Rac1-PAK1-Arp2/3 signaling axis regulates CHIKV nsP1-induced filopodia and optimal viral genome replication

Alphavirus infection induces dramatic remodeling of host cellular membranes, producing filopodia-like and intercellular extensions. The formation of filopodia-like extensions has been primarily assigned to the replication protein nsP1, which binds and reshapes the host plasma membrane when expressed alone. While reported decades ago, the molecular mechanisms behind nsP1 membrane deformation remain unknown. Using mammalian epithelial cells and Chikungunya virus (CHIKV) as models, we characterized nsP1-induced membrane deformations as highly dynamic actin-rich lamellipodia and filopodia-like extensions. Through pharmacological inhibition and genetic invalidation, we identified the critical contribution of the Rac1 GTPase and its downstream effectors PAK1 and the actin nucleator Arp2 in nsP1-induced membrane deformation. An intact Rac1-PAK1-Arp2 signaling axis was also required for optimal CHIKV genome replication. Therefore, our results designate the Rac1-PAK1-Arp2 pathway as an essential signaling node for CHIKV infection and establish a parallel requirement for host factors involved in nsP1-induced plasma membrane reshaping and assembly of a functional replication complex.IMPORTANCEThe alphavirus nsP1 protein dramatically remodels host cellular membranes, resulting in the formation of filopodia-like extensions. Although described decades ago, the molecular mechanisms controlling these membrane deformations and their functional importance remain elusive. Our study provides mechanistic insight, uncovering the critical role of the Rac1 GTPase, along with its downstream effectors PAK1 and the actin nucleator Arp2, in the nsP1-associated phenotype. Furthermore, we demonstrate that the Rac1-PAK1-Arp2 pathway is essential for optimal CHIKV genome replication. Our findings establish a parallel in the cellular mechanisms governing nsP1-induced plasma membrane reshaping and the production of a functional replication complex in infected cells.

SirT7-mediated transcription of fascin in hyperglycemic glomerular endothelial cells contributes to EndMT in diabetic nephropathy

Diabetic nephropathy (DN) is the main cause of end-stage renal disease worldwide. It is reported that the endothelial-to-mesenchymal transition (EndMT) in glomerular endothelial cells plays an important role in DN. As a specific form of epithelial-to-mesenchymal transition, EndMT may involve common regulators of epithelial-to-mesenchymal transition. Fascin has been shown to mediate epithelial-to-mesenchymal transition. In addition, SirT7 has been confir med to contribute to inflammation in hyperglycemic endothelial cells via the modulation of gene transcription. In this study, we speculate that SirT7 modulates fascin transcription and is thus involved in EndMT in hyperglycemic glomerular endothelial cells. Our data indicate that α-smooth muscle actin (α-SMA) and fascin levels are increased, while CD31 levels are decreased in the kidneys of DN rats. Consistently, our cellular experiments reveal that high glucose treatment elevates fascin levels and induces EndMT in human glomerular endothelial cells (HGECs). Moreover, silencing of fascin inhibits EndMT in hyperglycaemic HGECs. In addition, SirT7 is found to be decreased in hyperglycemic cells and in the kidneys of DN mice. Moreover, the inhibition of SirT7 increases fascin level and mediates EndMT. An increase in SirtT7 expression decreases fascin expression, inhibits EndMT, and improves renal function in hyperglycemic cells and DN mice. SirT7 is found to bind to the promoter region of fascin. In summary, the present study indicates that SirT7 transcribes fascin to contribute to hyperglycemia-induced EndMT in DN patients.

The Bombyx mori singed Gene Is Involved in the High-Temperature Resistance of Silkworms

Temperature is an important factor in the growth, development, survival, and reproduction of organisms. The high-temperature resistance mechanism of insects may be significant for use in the prevention and control of insect pests. The silkworm, Bombyx mori, is an important Lepidoptera model species for studies on pest control in agriculture and forestry. We identified a gene in B. mori, the B. mori singed (Bmsn) gene, which is involved in the high-temperature resistance of silkworms. Sn proteins are highly conserved among species in many taxonomic groups. The overexpression of the Bmsn gene promoted the proliferation of silkworm cells, reduced oxidation, and reduced the accumulation of reactive oxygen species under stress. Interfering with the Bmsn gene had the opposite result. We constructed a transgenic B. mori strain that overexpressed the Bmsn gene. The physiological traits of the transgenic strain were significantly improved, and it had stronger high-temperature resistance. The Bmsn gene is involved in the process by which fat bodies respond to high-temperature stress. These findings provide insights into the mechanism of high-temperature resistance of insects and offer a new perspective on agricultural and forestry pest control.

Fascin - F-actin interaction studied by molecular dynamics simulation and protein network analysis

Actin bundles are an important component of cellular cytoskeleton and participate in the movement of cells. The formation of actin bundles requires the participation of many actin binding proteins (ABPs). Fascin is a member of ABPs, which plays a key role in bundling filamentous actin (F-actin) to bundles. However, the detailed interactions between fascin and F-actin are unclear. In this study, we construct an atomic-level structure of fascin - F-actin complex based on a rather poor cryo-EM data with resolution of 20 nm. We first optimized the geometries of the complex by molecular dynamics (MD) simulation and analyzed the binding site and pose of fascin which bundles two F-actin chains. Next, binding free energy of fascin was calculated by MM/GBSA method. Finally, protein structure network analysis (PSNs) was performed to analyze the key residues for fascin binding. Our results show that residues of K22, E27, E29, K41, K43, R110, R149, K358, R408 and K471 on fascin are important for its bundling, which are in good agreement with the experimental data. On the other hand, the consistent results indicate that the atomic-level model of fascin - F-actin complex is reliable. In short, this model can be used to understand the detailed interactions between fascin and F-actin, and to develop novel potential drugs targeting fascin.Communicated by Ramaswamy H. Sarma.

Fascin-1 expression is associated with neuroendocrine prostate cancer and directly suppressed by androgen receptor

BACKGROUND

Neuroendocrine prostate cancer (NEPC) is an aggressive form of prostate cancer, arising from resistance to androgen-deprivation therapies. However, the molecular mechanisms associated with NEPC development and invasiveness are still poorly understood. Here we investigated the expression and functional significance of Fascin-1 (FSCN1), a pro-metastasis actin-bundling protein associated with poor prognosis of several cancers, in neuroendocrine differentiation of prostate cancer.

METHODS

Differential expression analyses using Genome Expression Omnibus (GEO) database, clinical samples and cell lines were performed. Androgen or antagonist's cellular treatments and knockdown experiments were used to detect changes in cell morphology, molecular markers, migration properties and in vivo tumour growth. Chromatin immunoprecipitation-sequencing (ChIP-Seq) data and ChIP assays were analysed to decipher androgen receptor (AR) binding.

RESULTS

We demonstrated that FSCN1 is upregulated during neuroendocrine differentiation of prostate cancer in vitro, leading to phenotypic changes and NEPC marker expression. In human prostate cancer samples, FSCN1 expression is restricted to NEPC tumours. We showed that the androgen-activated AR downregulates FSCN1 expression and works as a transcriptional repressor to directly suppress FSCN1 expression. AR antagonists alleviate this repression. In addition, FSCN1 silencing further impairs in vivo tumour growth.

CONCLUSION

Collectively, our findings identify FSCN1 as an AR-repressed gene. Particularly, it is involved in NEPC aggressiveness. Our results provide the rationale for the future clinical development of FSCN1 inhibitors in NEPC patients.

Comprehensive analysis of the expression, prognosis and biological significance of FSCN family in clear cell renal cell carcinoma

Fascin (FSCN) is an actin-binding protein that serves a critical role in cell migration and invasion, contributing to tumor metastasis. However, there is little known about the function of FSCN family in kidney renal clear cell carcinoma (KIRC). The present study used the UALCAN, gene expression profiling interactive analysis, The Cancer Genome Atlas, cBioPortal, STRING and The Tumor Immune Estimation Resource databases to investigate the transcription level, genetic alteration and biological function of FSCNs in KIRC and their association with the prognosis value and immune cell infiltration in patients with KIRC. Results showed that the expression of FSCN1 and FSCN3 was markedly upregulated in patients with KIRC, while the expression of FSCN2 showed an opposite trend, which was the same as the experiments. Furthermore, the expression levels of FSCNs were associated with pathological stage, molecular subtypes and tumor grade. The expression levels of FSCNs were statistically correlated with the immune cell infiltration in KIRC. Higher expression levels of FSCN1 and FSCN3 were associated with worse overall survival (OS) and progression-free interval of patients bearing KIRC. Univariate and multivariate analysis demonstrated that FSCN2 was an independent risk factor for OS time in KIRC. Furthermore, mutations in FSCNs were significantly associated with poor OS and progression-free survival in patients with KIRC. The FSCNs were involved in pathways including focal adhesion, endocytosis, hypertrophic cardiomyopathy, regulation of actin cytoskeleton. The results indicated that FSCN2 might serve as an independent prognostic factor for OS of KIRC and that FSCN1 and FSCN3 can be used as favorable biomarkers for predicting clinical outcomes in KIRC.

The actin-bundling protein Fascin-1 modulates ciliary signalling

Primary cilia are microtubule-based cell organelles important for cellular communication. Since they are involved in the regulation of numerous signalling pathways, defects in cilia development or function are associated with genetic disorders, collectively called ciliopathies. Besides their ciliary functions, recent research has shown that several ciliary proteins are involved in the coordination of the actin cytoskeleton. Although ciliary and actin phenotypes are related, the exact nature of their interconnection remains incompletely understood. Here, we show that the protein BBS6, associated with the ciliopathy Bardet-Biedl syndrome, cooperates with the actin-bundling protein Fascin-1 in regulating filopodia and ciliary signalling. We found that loss of Bbs6 affects filopodia length potentially via attenuated interaction with Fascin-1. Conversely, loss of Fascin-1 leads to a ciliary phenotype, subsequently affecting ciliary Wnt signalling, possibly in collaboration with BBS6. Our data shed light on how ciliary proteins are involved in actin regulations and provide new insight into the involvement of the actin regulator Fascin-1 in ciliogenesis and cilia-associated signalling. Advancing our knowledge of the complex regulations between primary cilia and actin dynamics is important to understand the pathogenic consequences of ciliopathies.

DIAPH3 condensates formed by liquid-liquid phase separation act as a regulatory hub for stress-induced actin cytoskeleton remodeling

Membraneless condensates, such as stress granules (SGs) and processing bodies (P-bodies), have attracted wide attention due to their unique feature of rapid response to stress without first requiring nuclear feedback. In this study, we identify diaphanous-related formin 3 (DIAPH3), an actin nucleator, as a scaffold protein to initiate liquid-liquid phase separation (LLPS) and form abundant cytosolic phase-separated DIAPH3 granules (D-granules) in mammalian cells such as HeLa, HEK293, and fibroblasts under various stress conditions. Neither mRNAs nor known stress-associated condensate markers, such as G3BP1, G3BP2, and TIA1 for SGs and DCP1A for P-bodies, are detected in D-granules. Using overexpression and knockout of DIAPH3, pharmacological interventions, and optogenetics, we further demonstrate that stress-induced D-granules spatially sequester DIAPH3 within the condensation to inhibit the assembly of actin filaments in filopodia. This study reveals that D-granules formed by LLPS act as a regulatory hub for actin cytoskeletal remodeling in response to stress.

Molecular dynamics simulation study on the structures of fascin mutants

Fascin is a filamentous actin (F-actin) bundling protein, which cross-links F-actin into bundles and becomes an important component of filopodia on the cell surface. Fascin is overexpressed in many types of cancers. The mutation of fascin affects its ability to bind to F-actin and the progress of cancer. In this paper, we have studied the effects of residues of K22, K41, K43, K241, K358, K399, and K471 using molecular dynamics (MD) simulation. For the strong-effect residues, that is, K22, K41, K43, K358, and K471, our results show that the mutation of K to A leads to large values of root mean square fluctuation (RMSF) around the mutated residues, indicating those residues are important for the flexibility and thermal stability. On the other hand, based on residue cross-correlation analysis, alanine mutations of these residues reinforce the correlation between residues. Together with the RMSF data, the local flexibility is extended to the entire protein by the strong correlations to influence the dynamics and function of fascin. By contrast, for the mutants of K241A and K399A those do not affect the function of fascin, the RMSF data do not show significant differences compared with wild-type fascin. These findings are in a good agreement with experimental studies.

Notch-associated lncRNAs profiling circuiting epigenetic modification in colorectal cancer

Background

Colorectal cancer (CRC) is one of the most prevalent digestive cancers, ranking the 2nd cause of cancer-related fatality worldwide. The worldwide burden of CRC is predicted to rise by 60% by 2030. Environmental factors drive, first, inflammation and hence, cancer incidence increase.

Main

The Notch-signaling system is an evolutionarily conserved cascade, has role in the biological normal developmental processes as well as malignancies. Long non-coding RNAs (LncRNAs) have become major contributors in the advancement of cancer by serving as signal pathways regulators. They can control gene expression through post-translational changes, interactions with micro-RNAs or down-stream effector proteins. Recent emerging evidence has emphasized the role of lncRNAs in controlling Notch-signaling activity, regulating development of several cancers including CRC.

Conclusion

Notch-associated lncRNAs might be useful prognostic biomarkers or promising potential therapeutic targets for CRC treatment.

Therefore, here-in we will focus on the role of “Notch-associated lncRNAs in CRC” highlighting “the impact of Notch-associated lncRNAs as player for cancer induction and/or progression.”

Graphical Abstract

Development and validation of an LC-MS/MS method for the quantification of fascin proteins in human serum

Background: Fascin is an actin-bundling protein that has been linked to tumor cell migration, invasion, metastasis, disease progression and mortality, thus serving as a novel cancer biomarker. Bioanalytical methods to measure fascin in biological matrices are sparsely reported, while accurate quantitation of fascin levels may lend support for fascin as a promising therapeutic target. Method: An LC-MS/MS-based method involving protein precipitation, enzymatic digestion and solid phase extraction was developed and validated for the quantitation of fascin in human serum. Linearity over a calibration range of 5-500 ng/ml with a LLOQ of 5 ng/ml, great accuracy and precision, excellent parallelism as well as high extraction recovery were achieved. Conclusion: This method provides a valuable tool for anticancer drug development and cancer treatment.

p53 Related Protein Kinase is Required for Arp2/3-Dependent Actin Dynamics of Hemocytes in Drosophila melanogaster

Cells extend membrane protrusions like lamellipodia and filopodia from the leading edge to sense, to move and to form new contacts. The Arp2/3 complex sustains lamellipodia formation, and in conjunction with the actomyosin contractile system, provides mechanical strength to the cell. Drosophila p53-related protein kinase (Prpk), a Tsc5p ortholog, has been described as essential for cell growth and proliferation. In addition, Prpk interacts with proteins associated to actin filament dynamics such as α-spectrin and the Arp2/3 complex subunit Arpc4. Here, we investigated the role of Prpk in cell shape changes, specifically regarding actin filament dynamics and membrane protrusion formation. We found that reductions in Prpk alter cell shape and the structure of lamellipodia, mimicking the phenotypes evoked by Arp2/3 complex deficiencies. Prpk co-localize and co-immunoprecipitates with the Arp2/3 complex subunit Arpc1 and with the small GTPase Rab35. Importantly, expression of Rab35, known by its ability to recruit upstream regulators of the Arp2/3 complex, could rescue the Prpk knockdown phenotypes. Finally, we evaluated the requirement of Prpk in different developmental contexts, where it was shown to be essential for correct Arp2/3 complex distribution and actin dynamics required for hemocytes migration, recruitment, and phagocytosis during immune response.

Sulfiredoxin Promotes Cancer Cell Invasion through Regulation of the miR143-Fascin Axis

Intracellular antioxidant enzymes are critical for maintenance of redox homeostasis, but whether and how they contribute to the malignancy of cancer cells remains poorly understood. Sulfiredoxin (Srx) is a unique oxidoreductase in that it not only restores peroxidase activity of peroxiredoxins (Prxs) but also functions as a pivotal stimulator of oncogenic signaling. We found that abnormally high level of Srx promotes colorectal cancer (CRC) malignancy by stimulating gelatin degradation, invadopodia formation, and cell invasion. Fascin, an actin-bundling protein, was discovered and validated as one of the critical downstream targets of Srx activation. We demonstrated that depletion of Srx in CRC cells leads to upregulation of miR-143-3p, which mediates degradation of fascin mRNA through binding to conserved sites within the 3' untranslated region (UTR). Depletion of fascin in CRC cells recapitulates the effect of Srx loss, and restoration of fascin in Srx-depleted cells by miR-143-3p inhibitor or overexpression rescues defects in cell invasion. Therefore, our data demonstrate that the Srx-miR143-fascin axis plays a key role in promoting the malignancy of human CRC cells. In the future, the Srx-miR143-fascin axis can be used as a functional pathway to evaluate the efficacy of therapeutic drugs or be targeted to develop promising chemotherapeutics for treatment of CRC patients.

Visualising the cytoskeletal machinery in neuronal growth cones using cryo-electron tomography

Neurons extend axons to form the complex circuitry of the mature brain. This depends on the coordinated response and continuous remodelling of the microtubule and F-actin networks in the axonal growth cone. Growth cone architecture remains poorly understood at nanoscales. We therefore investigated mouse hippocampal neuron growth cones using cryo-electron tomography to directly visualise their three-dimensional subcellular architecture with molecular detail. Our data showed that the hexagonal arrays of actin bundles that form filopodia penetrate and terminate deep within the growth cone interior. We directly observed the modulation of these and other growth cone actin bundles by alteration of individual F-actin helical structures. Microtubules with blunt, slightly flared or gently curved ends predominated in the growth cone, frequently contained lumenal particles and exhibited lattice defects. Investigation of the effect of absence of doublecortin, a neurodevelopmental cytoskeleton regulator, on growth cone cytoskeleton showed no major anomalies in overall growth cone organisation or in F-actin subpopulations. However, our data suggested that microtubules sustained more structural defects, highlighting the importance of microtubule integrity during growth cone migration.

Summary: Cryo-electron tomographic reconstruction of neuronal growth cone subdomains reveals distinctive F-actin and microtubule cytoskeleton architectures and modulation at molecular detail.

LncRNA CRNDE promotes cell proliferation, migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis

Ovarian cancer seriously threatens the health of women. LncRNA CRNDE is known to be upregulated in ovarian cancer. However, the mechanism by which CRNDE regulates the progress of ovarian cancer is largely unknown. MTT assay was applied to measure the cell viability. Colony formation assay was used to measure the cell proliferation. Cell migration was tested by wound healing, and Transwell assay was performed to detect cell invasion. In addition, the expression of miR-423-5p, CRNDE and FSCN1 were detected by RT-qPCR and western blotting, respectively. Meanwhile, dual-luciferase reporter assay and RIP assay were performed to explore the correlation between miR-423-5p and CRNDE (or FSCN1). CRNDE and FSCN1 were upregulated in ovarian cancer cells (SKOV3, CAOV-3, IGROV1, A2780 and C13K), while miR-423-5p was downregulated. Moreover, silencing of FSCN1/CRNDE significantly decreased proliferation, migration and invasion of ovarian cancer cells (SKOV3 and CI3K) via suppressing MMP-2 and MMP-9. In addition, CRNDE could sponge miR-423-5p, and FSCN1 was confirmed to be the direct target of miR-423-5p. Furthermore, CRNDE knockdown-induced inhibition of FSCN1 was notably reversed by miR-423-5p downregulation. Knockdown of CRNDE inhibited cell proliferation, migration and invasion of ovarian cancer via miR-423-5p/FSCN1 axis. Thus, CRNDE may serve a new target for ovarian cancer.

Alternative NF-κB Signaling Discriminates Induction of the Tumor Marker Fascin by the Viral Oncoproteins Tax-1 and Tax-2 of Human T-Cell Leukemia Viruses

Transcriptional regulation of the actin-bundling protein and tumor marker Fascin is highly diverse depending on cell and tumor type. Previously, we discovered that the viral oncoprotein Tax-1 of human T-cell leukemia virus type 1 (HTLV-1) considerably enhances Fascin expression in T-cells, depending on classical NF-κB signaling. In this study, we asked if the non-oncogenic Tax-2 of the related HTLV-2 is still able to induce Fascin by using luciferase assays, immunoblot, and qPCR. We found that Tax-2 only slightly induces Fascin expression compared to Tax-1; however, both Tax-1 and Tax-2 comparably activated a 1.6 kb fragment in the human Fascin promoter including Tax-responsive elements. Furthermore, we identified a link between Tax-induced activity of the alternative NF-κB pathway and Fascin induction. While treatment with the second mitochondria-derived activator of caspases (SMAC)-mimetic AZD5582, a compound known to robustly activate alternative NF-κB signaling, did not induce Fascin, combination of AZD5582 with activation of classical NF-κB signaling by Tax-2 significantly induced Fascin expression. In conclusion, our data demonstrate that both classical and alternative NF-κB activity are necessary for strong Fascin induction by the viral Tax oncoproteins, thus, shedding new light on the regulation of Fascin in T-cells and during viral transformation.

Fascin expression persists with fibronectin in embryonic rat hepatoblasts

Both fascin and fibronectin are known to play important roles in cell adhesion and migration. They are noted as tumor markers or inhibiting target for tumor treatment. In this study, embryonic rat livers were obtained to examine the expression of fascin and fibronectin during liver development. Then, the effect of fibronectin on fascin expression was investigated. At embryonic day (ED) 10.5, when the foregut endoderm began to form the liver bud and spread into the septum transversum, fibrous extracellular matrix was observed between the space where the liver bud and the septum transversum merged. At ED11.5, fibronectin was observed surrounding the cluster of fascin-positive hepatoblasts. At ED13.5, hematopoietic cells emerged and both fibronectin and fascin expression started to decline. Fascin and fibronectin appeared temporarily and disappeared by ED 14.5. Their expression was chronologically synchronized. Subsequently, the effect of fibronectin on fascin was examined by cultivation of hepatoblasts that were isolated from the ED13.5 rat liver. As a result, with fibronectin, fascin was positive in most hepatoblasts, although, without fibronectin, fascin expression was remarkably declined. Presently, there are few studies about the relationship between fascin and fibronectin. Our findings suggest that fibronectin could regulate fascin expression in rat hepatoblasts.

Do immunohistochemical studies have a role in predicting prognosis of laryngeal squamous cell carcinomas? CD44 and Fascin experience

BACKGROUND AND OBJECTIVES

The diagnosis of laryngeal squamous cell carcinoma (LSCC) can be made easily based on histopathological findings, but the relationship between morphological findings and prognosis is not clear. In addition to morphological findings, the use of novel markers may contribute to the development of new treatment strategies and improved patient prognosis. CD44, which is a cancer stem cell marker, and Fascin-1, an actin-binding protein has been associated with poor prognosis in many tumors. The aim of this study was to investigate the relationship between CD44 and Fascin-1 expression and clinicopathologic parameters in LSCC and their roles in the determination of clinical behavior and prognosis. The aim of this study is to investigate whether CD44 and Fascin have a relationship with clinicopathological parameters and have a role in determining clinical behavior and prognosis in LSCC.

METHODS

130 patients who were operated in our hospital for LSCC between 2012 and 2018 were included in this study. Fascin-1 and CD44 stains were applied immunohistochemically to the paraffin blocks of the tumors. Immunostained specimens were scored according to the intensity of staining and the percentage of staining for each marker. Overall scores were summed and was designated as immunoreactivity score (IRS). Finally, IRS was categorized into two groups; Low and High CD44/Fascin IRS.

RESULTS

There were no statistically significant differences between low and high CD44 and Fascin IRS groups in terms of clinicopathologic parameters, overall and disease-free survival (p> 0.05).

CONCLUSION

Immunhistochemical studies are not yet sufficient to predict patient prognosis. Morphological findings still remain of priority and importance for pathologists.

The role of fascin in carcinogenesis and embryo implantation

The cytoskeleton, with its actin bundling proteins, plays crucial roles in a host of cellular function, such as cancer metastasis, antigen presentation and trophoblast migration and invasion, as a result of cytoskeletal remodeling. A key player in cytoskeletal remodeling is fascin. Upregulation of fascin induces the transition of epithelial phenotypes to mesenchymal phenotypes through complex interaction with transcription factors. Fascin expression also regulates mitochondrial F-actin to promote oxidative phosphorylation (OXPHOS) in some cancer cells. Trophoblast cells, on the other hand, exhibit similar physiological functions, involving the upregulation of genes crucial for its migration and invasion. Owing to the similar tumor-like characteristics among cancer and trophoblats, we review recent studies on fascin in relation to cancer and trophoblast cell biology; and based on existing evidence, link fascin to the establishment of the maternal-fetal interface.

Proteomes, kinases and signalling pathways in virus-induced filopodia, as potential antiviral therapeutics targets

Filopodia are thin finger-like protrusions at the surface of cells that are internally occupied with bundles of tightly parallel actin filaments. They play significant roles in cellular physiological processes, such as adhesion to extracellular matrix, guidance towards chemo-attractants and in wound healing. Filopodia were recently reported to play important roles in viral infection including initial viral attachment to host cells, cell surfing, viral trafficking, internalization, budding, virus release and spread to other cells in a form that would avoid the host immune system. The detailed virus-host protein interactions underlying most of these processes remain to be elucidated. This review will describe some reported virus-host protein interactions on filopodia with the aim of identifying potential new anti-virus therapeutic targets. Exploring this research area may lead to the development of novel classes of anti-viral therapeutics that can block signalling pathways used by the virus to trigger filopodia formation. Successful compounds would inhibit initial virus attachment, formation of filopodia, expression of putative virus binding protein, extracellular virus trafficking, and budding.

Emerging Role of Fascin-1 in the Pathogenesis, Diagnosis, and Treatment of the Gastrointestinal Cancers

Simple Summary

Gastrointestinal (GI) cancers, including esophageal, gastric, colorectal, liver, and pancreatic cancers, remain as one of the leading causes of death worldwide, with a large proportion accounting for fatalities related to metastatic disease. The active involvement of fascin-1 in forming membrane protrusions crucial for cellular movement has been identified as an important molecular mechanism behind the phenotypic switch from the localized to the metastatic tumor. Thus, fascin-1 expression status in the malignant tissue has been utilized as an important component in determining the patient’s clinicopathological outcomes. In this review, we provide an up-to-date literature review of the role of fascin-1 in the initiation and metastatic progression of GI tract cancers, its involvement in patients’ clinical outcomes, and its potential as a therapeutic target.

Abstract

Gastrointestinal (GI) cancers, including esophageal, gastric, colorectal, liver, and pancreatic cancers, remain as one of the leading causes of death worldwide, with a large proportion accounting for fatalities related to metastatic disease. Invasion of primary cancer occurs by the actin cytoskeleton remodeling, including the formation of the filopodia, stereocilia, and other finger-like membrane protrusions. The crucial step of actin remodeling in the malignant cells is mediated by the fascin protein family, with fascin-1 being the most active. Fascin-1 is an actin-binding protein that cross-links filamentous actin into tightly packed parallel bundles, giving rise to finger-like cell protrusions, thus equipping the cell with the machinery necessary for adhesion, motility, and invasion. Thus, fascin-1 has been noted to be a key component for determining patient diagnosis and treatment plan. Indeed, the overexpression of fascin-1 in GI tract cancers has been associated with a poor clinical prognosis and metastatic progression. Moreover, fascin-1 has received attention as a potential therapeutic target for metastatic GI tract cancers. In this review, we provide an up-to-date literature review of the role of fascin-1 in the initiation of GI tract cancers, metastatic progression, and patients’ clinical outcomes.

Effect of rs67085638 in long non-coding RNA (CCAT1) on colon cancer chemoresistance to paclitaxel through modulating the microRNA-24-3p and FSCN1

It has been reported that rs67085638 in long non-coding RNAs (lncRNA)-CCAT1 was associated with the risk of tumorigenesis. Also, CCAT1 could affect chemoresistance of cancer cells to paclitaxel (PTX) via regulating miR-24-3p and FSCN1 expression. In this study, we aimed to investigate the effect of rs67085638 on the expression of CCAT1/miR-24-3p/FSCN1 and the response of colon cancer to the treatment of PTX. 48 colon cancer patients were recruited and grouped by their genotypes of rs67085638 polymorphism as a CC group (N = 28) and a CT group (N = 20). PCR analysis, IHC assay and Western blot, TUNEL assay and flow cytometry were conducted. LncRNA-CCAT1 and FSCN1 mRNA/protein were overexpressed, whereas miR-24-3p was down-regulated in the CT-genotyped patients and cells compared with those in the CC-genotyped patients and cells. The survival of colon cancer cells was decreased, whereas the apoptosis of colon cancer cells was increased by PTX treatment in a dose-dependent manner. MiR-24-3p was validated to target lncRNA-CCAT1 and FSCN1 mRNA, and the overexpression of CCAT1 could reduce the expression of miR-24-3p although elevating the expression of FSCN1. Knockdown of lncRNA-CCAT1 partly reversed the suppressed growth of CT-genotyped tumours. And the knockdown of lncRNA-CCAT1 partly reversed the dysregulation of lncRNA-CCAT1 and FSCN1 mRNA/protein in rs67085638-CT + NC shRNA mice. The findings of this study demonstrated that the presence of the minor allele of rs67085638 increased the expression of CCAT1 and accordingly enhanced the resistance to PTX. Down-regulation of CCAT1 significantly re-stored the sensitivity to PTX of colon cancer cells.

Prognostic significance of FSCN family in multiple myeloma

Multiple myeloma (MM) is a hematologic tumor with monoclonal proliferation of malignant plasma cells in the bone marrow. Fascin (FSCN) is an actin-binding protein that plays a crucial role in cell migration and invasion, contributing to tumor metastasis. There are three members (FSCN1-3) in FSCN family. However, the prognostic role of FSCN family in MM remains unclear. In this study, we used four independent Gene Expression Omnibus (GEO) datasets to explore the relationships between FSCN1-3 expression profiles and patient survival in MM. We found that FSCN1 was dramatically down-regulated in MM compared to normal donors (p < 0.001) and monoclonal gammopathy of undetermined significance (MGUS) (p = 0.032). Patients with high expression of FSCN1 and FSCN2 had significantly longer OS (p = 0.023 and 0.028, respectively). Univariate and multivariate analysis showed that FSCN1 (p = 0.003, 0.002) and FSCN2 (p = 0.018, 0.013) were independent favorable prognostic factors for OS in MM. Moreover, the combination of high expression of FSCN1 and FSCN2 could effectively predict both longer EFS (p = 0.046) and OS (p = 0.015). Our study suggested that FSCN1 and FSCN2 can be used as favorable biomarkers for predicting clinical outcomes in MM.

Non-classical role of Galectin-3 in cancer progression: translocation to nucleus by carbohydrate-recognition independent manner

Galectin-3 is a carbohydrate-binding protein and regulates diverse functions, including cell proliferation and differentiation, mRNA splicing, apoptosis induction, immune surveillance and inflammation, cell adhesion, angiogenesis, and cancer-cell metastasis. Galectin-3 is also recommended as a diagnostic or prognostic biomarker of various diseases, including heart disease, kidney disease, and cancer. Galectin-3 exists as a cytosol, is secreted in extracellular spaces on cells, and is also detected in nuclei. It has been found that galectin-3 has different functions in cellular localization: (i) Extracellular galectin-3 mediates cell attachment and detachment. (ii) cytosolic galectin-3 regulates cell survival by blocking the intrinsic apoptotic pathway, and (iii) nuclear galectin-3 supports the ability of the transcriptional factor for target gene expression. In this review, we focused on the role of galectin-3 on translocation from cytosol to nucleus, because it happens in a way independent of carbohydrate recognition and accelerates cancer progression. We also suggested here that intracellular galecin-3 could be a potent therapeutic target in cancer therapy. [BMB Reports 2020; 53(4): 173-180].

The inhibitory effect of curcumin via fascin suppression through JAK/STAT3 pathway on metastasis and recurrence of ovary cancer cells

Background

Fascin is an actin-binding protein and highly expressed in ovarian cancer cells. It is associated with metastasis of cancer and may be a useful prognostic factor. Anticancer activity of curcumin is related to its effect on several signaling mechanisms. Although there have been many reports regarding the anticancer properties of curcumin, its inhibitory effects on migration and invasion of ovarian cancer cells, particularly in the context of fascin expression, have not been reported. The purpose of this study was to investigate the effect of curcumin on fascin expression in ovarian cancer cells and to propose a possible mechanism for the anticancer activity of curcumin through reduced fascin expression.

Methods

SKOV3, human epithelial ovary cancer cell line, was cultured with curcumin at various dose and duration. The fascin was quantified using cell viability test and Western blot. To determine the effect of curcumin on the upstream pathway of fascin expression, the signal transducer and activator of transcription 3 (STAT3) was analyzed by sandwich-ELISA. Attachment assay, migration assay and invasion assay were analyzed to approve the change of cellular invasiveness of ovary cancer after curcumin. To determine the morphological changes of ovarian cancer cells by curcumin, immunofluorescence was performed.

Results

MTS assays showed that cell viability was different at various concentration of curcumin, and as concentration increased, cell viability tended to decrease. Curcumin appears to suppress fascin expression, even with a minimal concentration and short exposure time. Also, curcumin may suppress fascin expression in ovarian cancer cells through STAT3 downregulation. The attachment assay, migration assay and invasion assay of the ovarian cancer cells exhibited a statistically significant decrease. Immunofluorescence revealed a change of cell shape from a typical form of uninfluenced cells to a more polygonal appearance, with a significant reduction in filopodia formation.

Conclusions

Curcumin reduces fascin expression through JAK/STAT3 pathway inhibition, which interferes with the cellular interactions essential for the metastasis and recurrence of ovarian cancer cells. Higher curcumin concentrations and longer exposure times concomitantly decreased fascin expression.

Crowding tunes the organization and mechanics of actin bundles formed by crosslinking proteins

Fascin and α-actinin form higher-ordered actin bundles that mediate numerous cellular processes including cell morphogenesis and movement. While it is understood crosslinked bundle formation occurs in crowded cytoplasm, how crowding affects the bundling activities of the two crosslinking proteins is not known. Here, we demonstrate how solution crowding modulates the organization and mechanical properties of fascin- and α-actinin-induced bundles, utilizing total internal reflection fluorescence and atomic force microscopy imaging. Molecular dynamics simulations support the inference that crowding reduces binding interaction between actin filaments and fascin or the calponin homology 1 domain of α-actinin evidenced by interaction energy and hydrogen bonding analysis. Based on our findings, we suggest a mechanism of crosslinked actin bundle assembly and mechanics in crowded intracellular environments.

Naringenin Sensitizes Resistant C6 Glioma Cells with a Repressive Impact on the Migrating Ability

Background:

Glioma, the most common form of a malignant brain tumour is characterised by a poor prognosis, which is attributable to its resistance against current therapeutic approaches. Temozolomide (TMZ), a DNA alkylating agent, is the first-line drug for glioma treatment. Long-term treatment using TMZ was reported to culminate in the development of resistance with overexpression of multidrug resistance 1 gene coded protein P-glycoprotein, which in turn releases the drugs from the tumour cells.

Purpose:

Thus, to circumvent such resistance issues, the current study attempted to explore the effect of naringenin (a flavanone) with proven antiglial tumour potential, in mitigating the features of TMZ resistance.

Methods:

Colony-forming assay, invasion assay and scratch wound assay were performed among the groups, namely tumour control (C6), vehicle control (V), naringenin (NGEN)-treated, drug-resistant tumour cells (C6R), and drug resistance cells added with NGEN (C6R+NGEN), to examine the impact of NGEN on migration and invasion. The effect of NGEN on filopodia length and density during cell migration was also studied in addition to the matrix metalloproteinases (MMP-2 and MMP-9) and p-ERK levels.

Results and Conclusion:

NGEN and C6R+NGEN groups had shown significant reduction (P < .01) in length and density of filopodia, colony formation, invasion and wound healing. Further, NGEN could also modify the assessed protein levels (P < .001), which were involved in migration and invasion in sensitive and resistant cells. Our study had provided the first evidence on NGEN-induced enhanced sensitivity against TMZ resistance with profound influence as an antimigratory and anti-invasive agent.

MiR-200b/c family inhibits renal fibrosis through modulating epithelial-to-mesenchymal transition via targeting fascin-1/CD44 axis

BACKGROUND

Renal fibrosis is the characteristic of all kinds of chronic kidney diseases (CKDs). Fascin-1 plays an important role in tumor development, but the roles of fascin-1 in renal fibrosis have not been studied. Here, we explored the role of fascin-1 in renal fibrosis and the potential mechanisms.

METHODS

Kidney unilateral ureteral obstruction (UUO) mouse model was used as an in vivo model, and proximal tubule epithelial cell lines treated with TGF-β1 were used as in vitro model of renal fibrosis. Cell transfection was performed to manipulate the expression of miR-200b/c, fascin-1 and CD44. Western blotting, qRT-PCR, immunohistochemistry or immunofluorescence assays were used to measure levels of miR-200b/c, fascin-1, CD44, and fibrosis and EMT-related markers. H&E and Masson stainings were used to examine the degree of injury and fibrosis in kidneys. Dual luciferase assay was used to examine the interaction between miR-200b/c family and fascin-1.

RESULTS

Fascin-1 and CD44 levels were both significantly up-regulated while miR-200b/c family was reduced in models of renal fibrosis. Furthermore, overexpression of miR-200b/c family and inhibition of fascin-1 or CD44 ameliorated renal fibrosis through suppressing EMT process. Mechanistically, miR-200b/c family directly and negatively regulated the expression of fascin-1. Overexpression of fascin-1 could reverse the effects of miR-200b/c family on renal fibrosis, and fascin-1 regulated renal fibrosis by activating CD44.

CONCLUSION

Our study is the first to show that fascin-1 plays a critical role in renal fibrosis. MiR-200b/c family could inhibit renal fibrosis through modulating EMT process by directly targeting fascin-1/CD44 axis.

Biology and Therapeutic Targets of Colorectal Serrated Adenocarcinoma; Clues for a Histologically Based Treatment against an Aggressive Tumor

Serrated adenocarcinoma (SAC) is a tumor recognized by the WHO as a histological subtype accounting for around 9% of colorectal carcinomas. Compared to conventional carcinomas, SACs are characterized by a worse prognosis, weak development of the immune response, an active invasive front and a frequent resistance to targeted therapy due to a high occurrence of KRAS or BRAF mutation. Nonetheless, several high-throughput studies have recently been carried out unveiling the biology of this cancer and identifying potential molecular targets, favoring a future histologically based treatment. This review revises the current evidence, aiming to propose potential molecular targets and specific treatments for this aggressive tumor.

The Inflammatory Milieu of Adamantinomatous Craniopharyngioma and Its Implications for Treatment

Pediatric Adamantinomatous Craniopharyngiomas (ACPs) are histologically benign brain tumors that often follow an aggressive clinical course. Their suprasellar location leaves them in close proximity to critical neurological and vascular structures and often results in significant neuroendocrine morbidity. Current treatment paradigms, involving surgical resection and radiotherapy, confer significant morbidity to patients and there is an obvious need to discover effective and safe alternative treatments. Recent years have witnessed significant efforts to fully detail the genomic, transcriptomic and proteomic make-up of these tumors, in an attempt to identify potential therapeutic targets. These studies have resulted in ever mounting evidence that inflammatory processes and the immune response play a critical role in the pathogenesis of both the solid and cystic portion of ACPs. Several inflammatory and immune markers have been identified in both the cyst fluid and solid tumor tissue of ACP. Due to the existence of effective agents that target them, IL-6 and immune checkpoint inhibitors seem to present the most likely immediate candidates for clinical trials of targeted immune-related therapy in ACP. If effective, such agents may result in a paradigm shift in treatment that ultimately reduces morbidity and results in better outcomes for our patients.

Targeting YAP1/LINC00152/FSCN1 Signaling Axis Prevents the Progression of Colorectal Cancer

As a transcription coactivator, Yes-associated protein 1 (YAP1)'s role in tumorigenesis is well established. However, the mechanism of YAP1-regulating long noncoding RNAs (lncRNA) in tumors is still largely unknown. Here, a YAP1 target gene, long intergenic noncoding RNA 00152 (LINC00152), which is highly expressed in colorectal cancer (CRC), is identified. The oncogenic functions of LINC00152 in CRC are demonstrated by a panel of in vitro and in vivo experiments. Further studies reveal the potential downstream mechanisms of LINC00152, which can act as a competing endogenous RNA sponging with miR-632 and miR-185-3p to regulate Fascin actin-bundling protein 1 (FSCN1) expression and thus promote the malignant proliferation and metastasis in CRC cells. Targeting the YAP1/LINC00152/FSCN1 axis inhibits the progression of CRC. This finding provides a new regulatory model of the "YAP1-lncRNA" in CRC, which gives rise to a new perspective, "YAP1/LINC00152/miR-632-miR-185-3p/FSCN1," to explore the cancer-promoting mechanism of YAP1 involved in CRC.

Development and Application of Cochlear Implant-Based Electric-Acoustic Stimulation of Spiral Ganglion Neurons

Cochlear implants are currently the most effective treatment for profound sensorineural hearing loss. However, their therapeutic effect is limited by the survival and proper physiological function of spiral ganglion neurons (SGNs), which are targeted by the cochlear implant. It is therefore critical to explore the mechanism behind the effect of electric-acoustic stimulation (EAS) on the targeted SGNs. In this work, a biocompatible cochlear implant/graphene EAS system was created by combining a cochlear implant to provide the electrically transformed sound stimulation with graphene as the conductive neural interface. SGNs were cultured on the graphene and exposed to EAS from the cochlear implant. Neurite extension of SGNs was accelerated with long-term stimulation, which might contribute to the development of growth cones. Our system allows us to study the effects of cochlear implants on SGNs in a low-cost and time-saving way, and this might provide profound insights into the use of cochlear implants and thus be of benefit to the populations suffering from sensorineural hearing loss.

The Emerging Role of Cytoskeletal Proteins as Reliable Biomarkers

Cytoskeletal proteins are essential building blocks of cells. More than 100 cytoskeletal and cytoskeleton-associated proteins are known and for some, their function and regulation are understood in great detail. Apart from cell shape and support, they facilitate many processes such as intracellular signaling and transport, and cancer related processes such as proliferation, migration, and invasion. During the last decade, comparative proteomic studies have identified cytoskeletal proteins as in vitro markers for tumor progression and metastasis. Here, these results are summarized and a number of unrelated studies are highlighted, identifying the same cytoskeletal proteins as potential biomarkers. These findings might indicate that the abundance of these potential markers of tumor progression is associated with the biological outcome and are independent of the cancer origin. This correlates well with recently published results from the Cancer Genome Atlas, indicating that cancers show remarkable similarities in their analyzed molecular information, independent of their organ of origin. It is postulated that the quantification of cytoskeletal proteins in healthy tissues, tumors, in adjacent tissues, and in stroma, is a great source of molecular information, which might not only be used to classify tumors, but more importantly to predict patients' outcome or even best treatment choices.

Spatiotemporal characterization of dynamic epithelial filopodia during zebrafish epiboly

BACKGROUND

During zebrafish epiboly, the embryonic cell mass, or blastoderm, spreads to enclose the yolk cell. The blastoderm consists of an outer epithelial sheet, the enveloping layer (EVL), and the underlying deep cell layer (DEL). Studies have provided insights into the mechanisms of EVL and deep cell epiboly, but little is known about the interactions between the two cell layers and what role they may play during epiboly.

RESULTS

We used live imaging to examine EVL basal protrusions. We identified them as filopodia based on f-actin content and localization of fluorescently tagged filopodial markers. A spatiotemporal analysis revealed that the largest number of EVL filopodia were present during early epiboly at the animal pole. In functional studies, expression of a constitutively active actin-bundling protein resulted in increased filopodial length and delayed gastrulation.

CONCLUSIONS

We identified protrusions on the basal surface of EVL cells as filopodia and showed that they are present throughout the EVL during epiboly. The largest number of filopodia was at the animal pole during early epiboly, which is when and where deep cell radial intercalations occur to the greatest extent. These findings suggest that EVL filopodia may function during epiboly to promote deep cell rearrangements during epiboly initiation.

The utility of CD83, fascin and CD23 in the differential diagnosis of primary mediastinal large B-cell lymphoma versus classic Hodgkin lymphoma

Primary mediastinal large B-cell lymphoma (PMBL) and classic Hodgkin lymphoma (CHL) are the most common large cell lymphomas arising in the mediastinum and are thought to be closely related histogenetically. Although the distinction between PMBL and CHL is usually straightforward, in some cases it is challenging and rarely these neoplasms have intermediate features and qualify for the diagnosis of mediastinal gray zone lymphoma (GZL). CD83 and fascin are markers of CHL and CD23 is a marker of PMBL. In this study we assess the utility of this combination of these immunohistochemical markers to distinguish CHL from PMBL. We retrospectively collected cases of PMBL, CHL and GZL from three centers. Tissue sections were stained with CD83, fascin and CD23. CD83 was expressed in the neoplastic cells of 100% of CHL (22/22), 93% of GZL (16/18) and 41% of PMBL (9/22). Similarly, fascin was positive in the neoplastic cells of 100% of CHL (22/22), 86% of GZL (18/21) and 32% of PMBL (7/22). CD23 was positive in 95% of PMBL (21/22), 67% of GZL (12/18) and 9% of CHL (2/22). CD83 and fascin are sensitive markers for CHL but not specific whereas CD23 is sensitive for PMBL and uncommon in CHL. The GZL cases in this study had an intermediate immunophenotype, but the results were closer to CHL than PMBL. A large panel of immunohistochemical studies is recommended to distinguish CHL from PMBL entities and we suggest that CD83, fascin and CD23 add value to panels designed for this differential diagnosis.

FSCN1 is an effective marker of poor prognosis and a potential therapeutic target in human tongue squamous cell carcinoma

To estimate the value of FSCN1 in evaluating the prognosis and guiding the targeted therapy for patients with tongue squamous cell carcinoma (TSCC). Using the Oncomine database, we found some genes especially FSCN1 differentially expressed between TSCC samples and tongue normal samples. So we compared FSCN1 expression between TSCC and normal cell lines and knocked down FSCN1 in TSCC cells to observe its influence on the viability and trans-migration in vitro and tumor growth in vivo. Then we measured FSCN1 expression in human cancer tissues and adjacent non-carcinoma tissues (ANT) and explored the relationship between FSCN1 expression and clinical pathological factors and prognosis in TSCC patients. We found that FSCN1 is expressed higher in TSCC cells than in normal cells. Knockdown of FSCN1 reduced TSCC cell viability and trans-migration in vitro and impaired tumor growth in vivo. FSCN1 also expressed higher in human TSCC than in ANT. In addition, FSCN1 expression was related to N classification, clinical stage and relapse. TSCC patients with over-expression of FSCN1 had worse prognosis. In conclusion, over-expression of FSCN1 indicates worse prognosis for patients with TSCC and FSCN1 may be a potential prognostic biomarker and therapeutic target in TSCC.

The Antiparallel Dimerization of Myosin X Imparts Bundle Selectivity for Processive Motility

Myosin X is an unconventional actin-based molecular motor involved in filopodial formation, microtubule-actin filament interaction, and cell migration. Myosin X is an important component of filopodia regulation, localizing to tips of growing filopodia by an unclear targeting mechanism. The native α-helical dimerization domain of myosin X is thought to associate with antiparallel polarity of the two amino acid chains, making myosin X the only myosin that is currently considered to form antiparallel dimers. This study aims to determine if antiparallel dimerization of myosin X imparts selectivity toward actin bundles by comparing the motility of parallel and antiparallel dimers of myosin X on single and fascin-bundled actin filaments. Antiparallel myosin X dimers exhibit selective processivity on fascin-bundled actin and are only weakly processive on single actin filaments below saturating [ATP]. Artificial forced parallel dimers of myosin X are robustly processive on both single and bundled actin, exhibiting no selectivity. To determine the relationship between gating of the reaction steps and observed differences in motility, a mathematical model was developed to correlate the parameters of motility with the biochemical and mechanical kinetics of the dimer. Results from the model, constrained by experimental data, suggest that the probability of binding forward, toward the barbed end of the actin filament, is lower in antiparallel myosin X on single actin filaments compared to fascin-actin bundles and compared to constructs of myosin X with parallel dimerization.

Long non-coding RNA ZEB1-AS1 regulates miR-200b/FSCN1 signaling and enhances migration and invasion induced by TGF-β1 in bladder cancer cells

Background

The effect of competing endogenous RNA (ceRNA) can regulate gene expression by competitively binding microRNAs. Fascin-1 (FSCN1) plays an important role in the regulation of cellular migration and invasion during tumor progression, but how its regulatory mechanism works through the ceRNA effect is still unclear in bladder cancer (BLCA).

Methods

The role of fascin-1, miR-200b, and ZEB1-AS1 in BLCA was investigated in vitro and in vivo. The interaction between fascin-1, miR-200b, and ZEB1-AS1 was identified using bioinformatics analysis, luciferase activity assays, RNA-binding protein immunoprecipitation (RIP), quantitative PCR, and western blotting. Loss (or gain)-of-function experiments were performed to investigate the biological roles of miR-200b and ZEB1-AS1 on migration, invasion, proliferation, cell apoptosis, and cell cycle.

Results

ZEB1-AS1 functions as a competing endogenous RNA in BLCA to regulate the expression of fascin-1 through miR-200b. Moreover, the oncogenic long non-coding RNA ZEB1-AS1 was highly expressed in BLCA and positively correlated with high tumor grade, high TNM stage, and reduced survival of patients with BLCA. Moreover, ZEB1-AS1 downregulated the expression of miR-200b, promoted migration, invasion, and proliferation, and inhibited apoptosis in BLCA. Furthermore, we found TGF-β1 induced migration and invasion in BLCA by regulating the ZEB1-AS1/miR-200b/FSCN1 axis.

Conclusion

The observations in this study identify an important regulatory mechanism of fascin-1 in BLCA, and the TGF-β1/ZEB1-AS1/miR-200b/FSCN1 axis may serve as a potential target for cancer therapeutic purposes.

Electronic supplementary material

The online version of this article (10.1186/s13046-019-1102-6) contains supplementary material, which is available to authorized users.

Human papilloma virus infection and fascin over-expression in squamous cell carcinoma of the cervix

Background: Human papilloma virus (HPV) is involved in development of almost all cervical cancers, mainly through the subversion of cellular mechanisms of growth control. Fascin plays central role in subsequent cell transformation events. Fascin mediates stabilization of parallel actin bundles where cellular protrusions are formed; this represents primary stages of cell migration and metastasis. Immunohistochemical assays have shown up-regulation of fascin expression in many epithelial and non-epithelial neoplasms. Therefore, the aim of this study was to investigate HPV infection and fascin expression in samples of cervical cancer.

Methods: Of 66 patients with confirmed SCC, formalin-fixed specimens, embedded in paraffin blocks were evaluated for HPV infection with nested multiplex polymerase chain reaction (NM-PCR) and for fascin expression with immunohistochemical assays. Statistical analysis was performed using Wilcoxon rank-sum test and SPSS software. A p<0.05 was considered for statistical significance.

Results: Of 66 samples, 52 (78.7%) were found positive for HPV infection and fascin over-expression was shown in all squamous cell carcinoma samples.

Conclusion: This study showed fascin overexpression in squamous cell carcinoma of the cervix which might be involved in metastasis of cancers induced by some types of HPV, hypothetically through attenuation of inter-cellular adhesions, and induction of cell motility

Inhibition of fascin in cancer and stromal cells blocks ovarian cancer metastasis

OBJECTIVE

Ovarian cancer (OvCa) metastasis requires the coordinated motility of both cancer and stromal cells. Cellular movement is a dynamic process that involves the synchronized assembly of f-actin bundles into cytoskeletal protrusions by fascin. Fascin directly binds f-actin and is an integral component of filopodia, lamellapodia and stress fibers. Here, we examine the expression pattern and function of fascin in the cancer and stromal cells of OvCa tumors.

METHODS

Fascin expression was evaluated in human cells and tissues using immunohistochemistry and immunofluorescence. The functional role of fascin in cancer and stromal cells was assessed with in vitro functional assays, an ex vivo colonization assay and in vivo metastasis assays using siRNA/shRNA and an inhibitor. The effect of fascin inhibition on Cdc42 and Rac1 activity was evaluated using GTPase activity assays and immunofluorescence.

RESULTS

Fascin expression was found to be higher in the stromal cell, when compared to the cancer cell, compartment of ovarian tumors. The low expression of fascin in the cancer cells of the primary tumor indicated a favorable prognosis for non-serous OvCa patients. In vitro, both knockdown and pharmacologic inhibition of fascin decreased the migration of cancer and stromal cells. The inhibition of fascin impaired Cdc42 and Rac1 activity in cancer cells, and cytoskeletal reorganization in the cancer and stromal cells. Inhibition of fascin ex vivo blocked OvCa cell colonization of human omental tissue and in vivo prevented and reduced OvCa metastases in mice. Likewise, knockdown of fascin specifically in the OvCa cells using a fascin-specific lentiviral-shRNA also blocked metastasis in vivo.

CONCLUSION

This study reveals the therapeutic potential of pharmacologically inhibiting fascin in both cancer and stromal cells of the OvCa tumor microenvironment.

Anti-Migration and Anti-Invasion Effects of Curcumin via Suppression of Fascin Expression in Glioblastoma Cells

Background

The natural compound curcumin was known to inhibit migration and invasion of glioblastoma (GBM) cells. Fascin, a kind of actin-binding proteins, is correlated with migration and invasion of GBM cells. The purpose of this study was to investigate anti-migration and anti-invasion effects of curcumin via suppression of fascin expression in GBM cells.

Methods

U87 cell line was used as an experimental model of GBM. Fascin was quantified by Western blot analysis. And, the signal transducer and activator of transcription 3 (STAT3), known to play an important role in migration and invasion of tumor cells, were analyzed by sandwich-ELISA. Migration and invasion capacities were assessed by attachment, migration and invasion assays. Cellular morphology was demonstrated by immunofluorescence.

Results

At various concentrations of curcumin and exposure times, fascin expression decreased. After temporarily exposure to 10 µM/L curcumin during 6 hours as less invasive concentration and time, fascin expression temporarily decreased at 12 hours (18.4%, p=0.024), and since then recovered. And, the change of phosphrylated STAT3 level also reflected the temporarily decreased pattern of fascin expression at 12 hours (19.7%, p=0.010). Attachment, migration, and invasion capacities consistently decreased at 6, 12, and 24 hours. And, immunofluorescence showed the change of shape and the reduction of filopodia formation in cells.

Conclusion

Curcumin is likely to suppress the fascin expression in GBM cells, and this might be a possible mechanism for anti-migration and anti-invasion effects of Curcumin via inhibition of STAT3 phosphorylation.

Lymphatic Vessel Network Structure and Physiology

The lymphatic system is comprised of a network of vessels interrelated with lymphoid tissue, which has the holistic function to maintain the local physiologic environment for every cell in all tissues of the body. The lymphatic system maintains extracellular fluid homeostasis favorable for optimal tissue function, removing substances that arise due to metabolism or cell death, and optimizing immunity against bacteria, viruses, parasites, and other antigens. This article provides a comprehensive review of important findings over the past century along with recent advances in the understanding of the anatomy and physiology of lymphatic vessels, including tissue/organ specificity, development, mechanisms of lymph formation and transport, lymphangiogenesis, and the roles of lymphatics in disease. © 2019 American Physiological Society. Compr Physiol 9:207-299, 2019.

Influence of cross-linkers on ezrin-bound minimal actin cortices

The actin cortex is a thin network coupled to the plasma membrane of cells, responsible for e.g., cell shape, motility, growth and division. Several model systems for minimal actin cortices (MACs) have been discussed in literature trying to mimic the complex interplay of membrane and actin. We recapitulate on different types of MACs using either three dimensional droplet interfaces or lipid bilayers to which F-actin networks are attached to or planar lipid bilayers with bound actin networks. Binding of the network to the membrane interface significantly influences its properties as well as its dynamics. This in turn also influences, how cross-linkers as well as myosin motors act on the network. Here, we describe the coupling of a filamentous actin network to a model membrane via the protein ezrin, a member of the ezrin-radixin-moesin family, which forms a direct linkage between the plasma membrane and the cortical web. Ezrin binding to the membrane is achieved by the lipid PtdIns(4,5)P₂, while attachment to F-actin is mediated via the C-terminal domain of the protein leading to a two dimensional arrangement of actin filaments on the membrane. Addition of cross-linkers such as fascin and α-actinin influences the architecture of the actin network, which we have investigated by means of fluorescence microscopy. The results are discussed in terms of the dynamics of the filaments on the membrane surface.