Fascin protrusions in cell interactions

Expression of Fascin and SALL4 in odontogenic cysts and tumors: an immunohistochemical appraisal

Background

Various stemness markers (SOX2, OCT4, and NANOG) have been studied in odontogenic cysts and tumors. However, studies on SALL4 having similar properties of stemness has not been documented. Additionally, insight into fascin as a migratory molecule is less explored. In this study, the expression of SALL4 and fascin were evaluated in ameloblastoma, adenomatoid odontogenic tumor (AOT), odontogenic keratocyst (OKC), dentigerous cyst (DC), radicular cyst (RC), and calcifying odontogenic cyst (COC).

Methods

Semi-quantitative analysis of fascin and SALL4 immuno-positive cells was done in a total of 40 cases of ameloblastoma (11 plexiform, 12 follicular, 12 unicystic, and 5 desmoplastic) variants, 6 cases of AOT, 15 each of OKC, DC, RC and 5 of COC. Chi-square test was applied to evaluate the association between SALL4 and fascin expression in odontogenic cysts and tumors.

Results

Fascin immunopositivity was observed in peripheral ameloblast-like cells, and the expression was weak or absent in stellate reticulum-like cells. A moderate to weak immune-reactivity to SALL4 was observed in the cytoplasm of ameloblastoma, epithelial cells of dentigerous and radicular cysts, having a marked inflammatory infiltrate, which was an interesting observation. COC and AOT had negative to weak expressions. No recurrence has been reported.

Conclusions

Expression of fascin in ameloblastomas elucidate their role in motility and localized invasion. Its expression in less aggressive lesions like DC, COC, AOT will incite to explore the other functional properties of fascin. SALL4 expression in the cytoplasm of odontogenic cysts and tumors may represent inactive or mutant forms which requires further validation.

The crucial role of fascin-1 in the pathogenesis, metastasis, and chemotherapeutic resistance of breast cancer

Breast cancer (BC) is the most common type of cancer in women to be diagnosed, and it is also the second leading cause of cancer death in women globally. It is the disease that causes the most life years adjusted for disability lost among women, making it a serious worldwide health issue. Understanding and interpreting carcinogenesis and metastatic pathways is critical for curing malignancy. Fascin-1 was recognized as an actin-bundling protein with parallel, rigid bundles as a result of the cross-linking of F-actin microfilaments. Increasing levels of fascin-1 have been associated with bad prognostic profiles, aggressiveness of clinical courses, and poor survival outcomes in a variety of human malignancies. Cancer cells that overexpress fascin-1 have higher capabilities for proliferation, invasion, migration, and metastasis. Fascin-1 is being considered as a potential target for therapy as well as a potential biomarker for diagnostics in a variety of cancer types. This review aims to provide an overview of the FSCN1 gene and its protein structure, elucidate its physiological and pathological roles, and throw light on its involvement in the initiation, development, and chemotherapeutic resistance of BC.

The Role of Fascin-1 in Human Urologic Cancers: A Promising Biomarker or Therapeutic Target?

Human cancer statistics show that an increased incidence of urologic cancers such as bladder cancer, prostate cancer, and renal cell carcinoma. Due to the lack of early markers and effective therapeutic targets, their prognosis is poor. Fascin-1 is an actin-binding protein, which functions in the formation of cell protrusions by cross-linking with actin filaments. Studies have found that fascin-1 expression is elevated in most human cancers and is related to outcomes such as neoplasm metastasis, reduced survival, and increased aggressiveness. Fascin-1 has been considered as a potential therapeutic target for urologic cancers, but there is no comprehensive review to evaluate these studies. This review aimed to provide an enhanced literature review, outline, and summarize the mechanism of fascin-1 in urologic cancers and discuss the therapeutic potential of fascin-1 and the possibility of its use as a potential marker. We also focused on the correlation between the overexpression of fascin-1 and clinicopathological parameters. Mechanistically, fascin-1 is regulated by several regulators and signaling pathways (such as long noncoding RNA, microRNA, c-Jun N-terminal kinase, and extracellular regulated protein kinases). The overexpression of fascin-1 is related to clinicopathologic parameters such as pathological stage, bone or lymph node metastasis, and reduced disease-free survival. Several fascin-1 inhibitors (G2, NP-G2-044) have been evaluated in vitro and in preclinical models. The study proved the promising potential of fascin-1 as a newly developing biomarker and a potential therapeutic target that needs further investigation. The data also highlight the inadequacy of fascin-1 to serve as a novel biomarker for prostate cancer.

FSCN1 Promotes Esophageal Carcinoma Progression Through Downregulating PTK6 via its RNA-Binding Protein Effect

Objective: Esophageal squamous cell carcinoma (ESCC) causes many deaths worldwide every year. Fascin actin-bundling protein 1(FSCN1) has been reported to be a promoter of ESCC via its actin-binding function, however, its new role as an RNA-binding protein (RBP) has not been investigated. Here, we explored the RBP role of FSCN1 in the development of ESCC. Methods: Whole-genome expression sequencing was performed to screen for altered genes after FSCN1 knockdown. RNA immunoprecipitation was performed to determine the target mRNA of FSCN1 as an RBP. In vitro experiments with ECA-109 and KYSE-150 and ex vivo experiments in tumor-bearing mice were performed to investigate the effects of FSCN1 and Protein Tyrosine Kinase 6 (PTK6) on ESCC progression. Results: FSCN1 could downregulate mRNA and the protein level of PTK6. The binding position of PTK6 (PTK6-T2) pre-mRNA to FSCN1 was determined. PTK6-T2 blocked the binding between FSCN1 and the pre-mRNA of PTK6, and thus reversed the promotion effect of FSCN1 on ESCC tumor progression via the AKT/GSK3β signaling pathway. Conclusion: A novel effect of FSCN1, RBP-binding with the pre-mRNA of PTK6, was confirmed to play an important role in ESCC progression. PTK6-T2, which is a specific inhibitor of FSCN1 binding to the pre-mRNA of PTK6, could impede the development of ESCC.

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.

Fascin in Gynecological Cancers: An Update of the Literature

Simple Summary

Fascin, an actin-binding protein, is upregulated in different types of human cancers. It is reportedly responsible for increasing the invasive and metastatic ability of cancer cells by reducing cell–cell adhesions. This review provides a brief overview of fascin and its interactions with other genes and oncoviruses to induce the onset and progression of cancer.

Abstract

Fascin is an actin-binding protein that is encoded by the FSCN1 gene (located on chromosome 7). It triggers membrane projections and stimulates cell motility in cancer cells. Fascin overexpression has been described in different types of human cancers in which its expression correlated with tumor growth, migration, invasion, and metastasis. Moreover, overexpression of fascin was found in oncovirus-infected cells, such as human papillomaviruses (HPVs) and Epstein-Barr virus (EBV), disrupting the cell–cell adhesion and enhancing cancer progression. Based on these findings, several studies reported fascin as a potential biomarker and a therapeutic target in various cancers. This review provides a brief overview of the FSCN1 role in various cancers with emphasis on gynecological malignancies. We also discuss fascin interactions with other genes and oncoviruses through which it might induce cancer development and progression.

Fascin actin-bundling protein 1 in human cancer: promising biomarker or therapeutic target?

Fascin actin-bundling protein 1 (FSCN1) is a highly conserved actin-bundling protein that cross links F-actin microfilaments into tight, parallel bundles. Elevated FSCN1 levels have been reported in many types of human cancers and have been correlated with aggressive clinical progression, poor prognosis, and survival outcomes. The overexpression of FSCN1 in cancer cells has been associated with tumor growth, migration, invasion, and metastasis. Currently, FSCN1 is recognized as a candidate biomarker for multiple cancer types and as a potential therapeutic target. The aim of this study was to provide a brief overview of the FSCN1 gene and protein structure and elucidate on its actin-bundling activity and physiological functions. The main focus was on the role of FSCN1 and its upregulatory mechanisms and significance in cancer cells. Up-to-date studies on FSCN1 as a novel biomarker and therapeutic target for human cancers are reviewed. It is shown that FSCN1 is an unusual biomarker and a potential therapeutic target for cancer.

Confinement Geometry Tunes Fascin-Actin Bundle Structures and Consequently the Shape of a Lipid Bilayer Vesicle

Depending on the physical and biochemical properties of actin-binding proteins, actin networks form different types of membrane protrusions at the cell periphery. Actin crosslinkers, which facilitate the interaction of actin filaments with one another, are pivotal in determining the mechanical properties and protrusive behavior of actin networks. Short crosslinkers such as fascin bundle F-actin to form rigid spiky filopodial protrusions. By encapsulation of fascin and actin in giant unilamellar vesicles (GUVs), we show that fascin-actin bundles cause various GUV shape changes by forming bundle networks or straight single bundles depending on GUV size and fascin concentration. We also show that the presence of a long crosslinker, α-actinin, impacts fascin-induced GUV shape changes and significantly impairs the formation of filopodia-like protrusions. Actin bundle-induced GUV shape changes are confirmed by light-induced disassembly of actin bundles leading to the reversal of GUV shape. Our study contributes to advancing the design of shape-changing minimal cells for better characterization of the interaction between lipid bilayer membranes and actin cytoskeleton.

How does fascin promote cancer metastasis?

Fascin is an F-actin-bundling protein that cross-links individual actin filaments into straight and stiff bundles. Fascin overexpression in cancer is strongly associated with poor prognosis and metastatic progression across different cancer types. It is well established that fascin plays a causative role in promoting metastatic progression. We will review the recent progress in our understanding of mechanisms underlying fascin-mediated cancer metastasis. This review will cover the biochemical basis for fascin-bundling activity, the mechanisms by which cancer cells upregulate fascin expression and the mechanism underlying fascin-mediated cancer cell migration, invasion, and metastatic colonization. We propose that fascin has broad roles in both metastatic dissemination and metastatic colonization. Understanding these mechanisms will be crucial to the development of anti-metastasis therapeutics targeting fascin.

Roles of Fascin mRNA expression in colorectal cancer: Meta-analysis and bioinformatics analysis

Fascin (encoded by FSCN1) is a globular actin cross-linking protein that is required for the formation of actin-based cell surface processes, which are critical for cell migration and cell-matrix adhesion. In the present study, a systematic meta-analysis and bioinformatics analysis was used to identify clinicopathological or prognostic parameters in patients with colorectal cancer. A total of 17 articles were included in the present study obtained from PubMed, Web of Science, Wanfang data, SinoMed and CNKI databases. Odd ratios (ORs) and the corresponding 95% confidence intervals (CIs) were used to estimate the prognostic significance of Fascin expression in patients with colorectal cancer, and the association between Fascin expression and clinicopathological factors. There was a significant correlation between high Fascin expression and poor overall survival rates in patients with colorectal cancer (OR=0.48; 95% CI, 0.38-0.60; P<0.000001). The meta-analysis showed that the expression of Fascin was significantly higher in colorectal cancer tissue compared with the normal mucosa (OR=0.13; 95% CI, 0.10-0.16; P<0.000001) and adenoma (OR=0.23; 95% CI, 0.15-0.34; P<0.000001). Fascin expression was also associated with depth of invasion (OR=0.31; 95% CI, 0.19-0.50; P<0.000001), lymph node metastasis (OR=3.07; 95% CI, 1.72-5.46; P=0.0001), Dukes stage (OR=0.14; 95% CI, 0.04-0.46; P=0.001), Tumor-Node-Metastasis stage (OR=0.38; 95% CI, 0.21-0.71; P=0.003) and dedifferentiation (OR=0.42; 95% CI, 0.19-0.94; P=0.04). According to the bioinformatics analyses, FSCN1 mRNA expression levels were higher in colorectal cancer and adenoma tissues compared with the normal tissues (P<0.05). According to TCGA, FSCN1 mRNA expression was associated with a less favorable prognosis in patients with colorectal cancer as an independent factor (P<0.05), and positively correlated with depth of invasion, microsatellite instability and low serum carcinoembryonic antigen levels in colorectal cancer. Taken together, the results of the present study suggested that Fascin expression is a potential marker of tumorigenesis, aggressiveness and poor prognosis in patients with colorectal cancer.

Long-term live-cell microscopy with labeled nanobodies delivered by laser-induced photoporation

Fluorescence microscopy is the method of choice for studying intracellular dynamics. However, its success depends on the availability of specific and stable markers. A prominent example of markers that are rapidly gaining interest are nanobodies (Nbs, ~ 15 kDa), which can be functionalized with bright and photostable organic fluorophores. Due to their relatively small size and high specificity, Nbs offer great potential for high-quality long-term subcellular imaging, but suffer from the fact that they cannot spontaneously cross the plasma membrane of live cells. We have recently discovered that laser-induced photoporation is well suited to deliver extrinsic labels to living cells without compromising their viability. Being a laser-based technology, it is readily compatible with light microscopy and the typical cell recipients used for that. Spurred by these promising initial results, we demonstrate here for the first time successful long-term imaging of specific subcellular structures with labeled nanobodies in living cells. We illustrate this using Nbs that target GFP/YFP-protein constructs accessible in the cytoplasm, actin-bundling protein Fascin, and the histone H2A/H2B heterodimers. With an efficiency of more than 80% labeled cells and minimal toxicity (~ 2%), photoporation proved to be an excellent intracellular delivery method for Nbs. Time-lapse microscopy revealed that cell division rate and migration remained unaffected, confirming excellent cell viability and functionality. We conclude that laser-induced photoporation labeled Nbs can be easily delivered into living cells, laying the foundation for further development of a broad range of Nbs with intracellular targets as a toolbox for long-term live-cell microscopy.

Upregulation of fascin-1 is involved in HIF-1α-dependent invasion and migration of hypopharyngeal squamous cell carcinoma

Fascin‑1 is an actin‑bundling protein, which specifically interacts with F‑actin to form parallel actin bundles, and participates in the regulation of cell adhesion, interactions and migration. However, the expression and regulatory mechanisms of fascin‑1 in hypopharyngeal squamous cell carcinoma (HSCC) remain poorly understood. The present study investigated the effects and underlying molecular mechanism of fascin‑1 on the invasion and metastasis of HSCC. The results demonstrated that fascin‑1 was overexpressed and correlated with lymph node metastasis and tumor‑node‑metastasis stage in HSCC tissues. Further in vitro study revealed that fascin‑1 promoted cell morphology polarization to increase the motility of FaDu cells. In addition, fascin‑1 significantly promoted the migration and invasion of FaDu cells. At the molecular level, fascin‑1 promoted cell invasion and migration by upregulating matrix metalloproteinase‑2 (MMP‑2) expression in FaDu cells. Immunohistochemical analysis revealed that a correlation existed between hypoxia inducible factor (HIF)‑1α and fascin‑1 expression in the HSCC tissues. Furthermore, the results from a cobalt chloride‑induced hypoxia model demonstrated that fascin‑1 may be upregulated by HIF‑1α in FaDu cells. Further analysis revealed that fascin‑1 knockdown significantly decreased the invasion of cells under hypoxia and partially reversed hypoxia‑induced MMP‑2 expression under hypoxia in FaDu cells. In conclusion, fascin‑1 was upregulated by HIF‑1α, and promoted the invasion and migration of HSCC cells; therefore, fascin‑1 may provide a potential target for the treatment of invasion and metastasis in HSCC.

Knockdown of fascin-1 expression suppresses cell migration and invasion of non-small cell lung cancer by regulating the MAPK pathway

Fascin-1 is a cytoskeletal protein and it can specifically bind to F-actin, it can be abnormally expressed in a variety of solid tumors. Fascin-1 was identified as a factor for poor prognosis in non-small cell lung cancer (NSCLC). However, the relevant molecular mechanisms are not yet fully understood. In this study, the fascin-1 knockdown cells were produced by lentivirus infection, and then cell proliferation, invasion and cell migration assay were used to investigate the role of fascin-1 in NSCLC cells. The MAPK pathway related proteins were determined by western blot. In the current study, lentivirus-mediated fascin-1 knockdown significantly decreased the proliferation of NSCLC cells. Furthermore, fascin-1 silencing partly inhibited cell invasion and migration. Inhibition of fascin-1 decreased the activity of the MAPK pathway. Therefore, targeting fascin-1 may inhibit the growth and metastasis of NSCLC cells, which is a potentially effective therapeutic strategy for treating NSCLC.

iTRAQ proteomic analysis of the interactions between Bombyx mori nuclear polyhedrosis virus and silkworm

The silkworm hemolymph is an important defense system against bacteria and viruses. In this study, silkworms were infected with Bombyx mori nuclear polyhedrosis virus to investigate the subsequent immune response at the protein level. Proteomes were analyzed before and after infection using isobaric tags for relative and absolute quantitation and LC-MS. A total of 456 differentially expressed proteins were identified, of which 179 were upregulated and 193 were downregulated. Changes in expression were validated by western blot for several proteins. Eleven of the differentially expressed proteins were involved in immunity. For example, modular serine protease and cecropin, which were downregulated, facilitate Toll and Imd signaling, while autophagy-related protein 3, which was upregulated, protects cells against oxidative damage. Collectively, the data highlight the unique interactions of baculovirus with the silkworm immune system.

BIOLOGICAL SIGNIFICANCE

This is the first time isobaric tags for relative and absolute quantitation were used to analyze B. mori proteins mobilized against B. mori nuclear polyhedrosis virus, and to investigate the immunity-associated proteome in B. mori. The results are a significant step towards a deeper understanding of immunoregulation in B. mori.

SIGNIFICANCE

This is the first time isobaric tags for relative and absolute quantitation were used to analyze B. mori proteins mobilized against B. mori nuclear polyhedrosis virus, and to investigate the immunity-associated proteome in B. mori. The results are a significant step towards a deeper understanding of immunoregulation in B. mori.

The Tax-Inducible Actin-Bundling Protein Fascin Is Crucial for Release and Cell-to-Cell Transmission of Human T-Cell Leukemia Virus Type 1 (HTLV-1)

The delta-retrovirus Human T-cell leukemia virus type 1 (HTLV-1) preferentially infects CD4⁺ T-cells via cell-to-cell transmission. Viruses are transmitted by polarized budding and by transfer of viral biofilms at the virological synapse (VS). Formation of the VS requires the viral Tax protein and polarization of the host cytoskeleton, however, molecular mechanisms of HTLV-1 cell-to-cell transmission remain incompletely understood. Recently, we could show Tax-dependent upregulation of the actin-bundling protein Fascin (FSCN-1) in HTLV-1-infected T-cells. Here, we report that Fascin contributes to HTLV-1 transmission. Using single-cycle replication-dependent HTLV-1 reporter vectors, we found that repression of endogenous Fascin by short hairpin RNAs and by Fascin-specific nanobodies impaired gag p19 release and cell-to-cell transmission in 293T cells. In Jurkat T-cells, Tax-induced Fascin expression enhanced virus release and Fascin-dependently augmented cell-to-cell transmission to Raji/CD4⁺ B-cells. Repression of Fascin in HTLV-1-infected T-cells diminished virus release and gag p19 transfer to co-cultured T-cells. Spotting the mechanism, flow cytometry and automatic image analysis showed that Tax-induced T-cell conjugate formation occurred Fascin-independently. However, adhesion of HTLV-1-infected MT-2 cells in co-culture with Jurkat T-cells was reduced upon knockdown of Fascin, suggesting that Fascin contributes to dissemination of infected T-cells. Imaging of chronically infected MS-9 T-cells in co-culture with Jurkat T-cells revealed that Fascin’s localization at tight cell-cell contacts is accompanied by gag polarization suggesting that Fascin directly affects the distribution of gag to budding sites, and therefore, indirectly viral transmission. In detail, we found gag clusters that are interspersed with Fascin clusters, suggesting that Fascin makes room for gag in viral biofilms. Moreover, we observed short, Fascin-containing membrane extensions surrounding gag clusters and clutching uninfected T-cells. Finally, we detected Fascin and gag in long-distance cellular protrusions. Taken together, we show for the first time that HTLV-1 usurps the host cell factor Fascin to foster virus release and cell-to-cell transmission.

Human T-cell leukemia virus type 1 (HTLV-1) is the only human retrovirus causing cancer and is transmitted via breast feeding, sexual intercourse, and cell-containing blood products. Efficient infection of CD4⁺ T-cells occurs via polarized budding of virions or via cell surface transfer of viral biofilms at a tight, specialized cell-cell contact, the virological synapse (VS). The viral protein Tax and polarization of the host cell cytoskeleton are crucial for formation of the VS, however, only little is known about the link between Tax and remodeling of the cytoskeleton to foster viral spread. The actin-bundling protein Fascin has evolved as a therapeutic target in several types of cancer. Here, we show that Fascin is also crucial for release and transmission of the tumorvirus HTLV-1. Since Fascin is a transcriptional target gene of Tax in T-cells, our work provides a link between Tax’s activity and virus transmission. Visualization of cell-cell contacts between infected and uninfected T-cells suggests a role of Fascin in viral transmission potentially by facilitating the transport of viral proteins to budding sites. Thus, Fascin is not only crucial for metastasis of tumors, but also for transmission of HTLV-1 and is a new cellular target to counteract HTLV-1.

Expression of Fascin-1 on human lung cancer and paracarcinoma tissue and its relation to clinicopathological characteristics in patients with lung cancer

BACKGROUND

Lung cancer poses a severe threat to human life. Biomarkers of cancers are helpful in the diagnosis and treatment of patients with cancers. Biomarkers of lung cancers are rare, and thus deserve further research.

OBJECTIVE

The objective of the present study was to explore the expression of Fascin-1 in human lung cancer and paracarcinoma tissue, its correlation with clinicopathological characteristics in patients with lung cancer, and study the possible relationship between Fascin-1 expression and clinical-biological behavior of lung cancer.

METHOD

This study used the MaxVision two-step immunohistochemical detection method to detect Fascin-1 expression in 84 of lung cancer and paracarcinoma tissues. This study set the expression of Fascin-1 in vascular endothelial cells as the positive control, and used phosphate buffered saline (replacing the primary antibodies) as negative control.

RESULT

Of all the 84 lung cancer tissues and paracarcinoma tissues, positive expression of the Fascin-1 protein were detected in 78 cases (92.9%) and 27 cases (32.1%), respectively, and the difference was statistically significant (P<0.05). Differences in Fascin-1 expression between different age groups, clinical stages, and lymph node metastases were statistically significant (P<0.05), while differences in Fascin-1 expression between sexes, tumor stages, and pathological types demonstrated no statistical significance (P>0.05). The survival times of the patients with different Fascin-1 protein-positive expressions in lung cancer tissues were statistically significant (P>0.05), while the survival times of the patients with different Fascin-1 protein-positive expressions in paracarcinoma tissues were not statistically significant (P>0.05).

CONCLUSION

In lung cancer, Fascin-1 expression was closely related to tumor invasion and metastasis, and the difference in expression of Fascin-1 had a significant effect on the survival time of the lung cancer patients. Therefore, Fascin-1 might be expected to serve as a possible potential biomarker of lung cancer.

Regulation of the tumor marker Fascin by the viral oncoprotein Tax of human T-cell leukemia virus type 1 (HTLV-1) depends on promoter activation and on a promoter-independent mechanism

Adult T-cell leukemia/lymphoma is a highly infiltrative neoplasia of CD4(+) T-lymphocytes that occurs in about 5% of carriers infected with the deltaretrovirus human T-cell leukemia virus type 1 (HTLV-1). The viral oncoprotein Tax perturbs cellular signaling pathways leading to upregulation of host cell factors, amongst them the actin-bundling protein Fascin, an invasion marker of several types of cancer. However, transcriptional regulation of Fascin by Tax is poorly understood. In this study, we identified a triple mode of transcriptional induction of Fascin by Tax, which requires (1) NF-κB-dependent promoter activation, (2) a Tax-responsive region in the Fascin promoter, and (3) a promoter-independent mechanism sensitive to the Src family kinase inhibitor PP2. Thus, Tax regulates Fascin by a multitude of signals. Beyond, using Tax-expressing and virus-transformed lymphocytes as a model system, our study is the first to identify the invasion marker Fascin as a novel target of PP2, an inhibitor of metastasis.

Clinicopathological significance of fascin-1 expression in patients with non-small cell lung cancer

PURPOSE

Fascin-1 promotes the formation of filopodia, lamellipodia, and microspikes of cell membrane after its cross-linking with F-actin, thereby enhancing the cell movement and metastasis and invasion of tumor cells. This study explored the fascin-1 protein's expression in non-small cell lung cancer (NSCLC) tissues and its relationship with clinical pathology and prognostic indicators.

METHODS

Immunohistochemical analysis was used to determine the expression of fascin-1 in NSCLC tissues. We used quantitative real-time polymerase chain reaction and western blot analysis to further verify the results. The fascin-1 expression and statistical method for clinical pathological parameters are examined by χ (2). Kaplan-Meier method is used for survival analysis. Cox's Proportional Hazard Model was used to conduct a combined-effect analysis for each covariate.

RESULTS

In 73 of the 128 cases, NSCLC cancer tissues (57.0%) were found with high expression of fascin-1, which was significantly higher than the adjacent tissues (35/128, 27.3%). The results suggested that the high expression of fascin-1 was significantly correlated with lymph node metastasis (P=0.022) and TNM stage (P=0.042). The high fascin-1 expression patients survived shorter than those NSCLC patients with low fascin-1 expression (P<0.05). Univariate analysis revealed that lymph node metastasis, TNM stage, and fascin-1 expression status were correlated with the overall survival. Similarly, lymph node metastasis, TNM stage, and fascin-1 expression status were significantly associated with the overall survival in multivariate analyses by using the Cox regression model.

CONCLUSION

The fascin-1 protein may be a useful prognostic indicator and hopeful new target for NSCLC patients.

Biomarkers distinguishing mammary fibroepithelial neoplasms: a tissue microarray study

AIM

To determine whether any markers in biopsy specimens were useful for distinguishing (1) fibroadenoma (FA) from benign phyllodes tumors (PTs); and (2) from benign borderline PTs of the breast.

MATERIALS AND METHODS

Specimens of 80 breast tumors (20 FA, 38 benign, 12 borderline, and 10 malignant PTs) diagnosed at Tri-Service General Hospital from 1986 to 2006 and 10 normal breast tissue were investigated immunohistochemically for the expression of 11 biomarkers including p53, Ki-67, topoisomerase IIα, p16, retinoblastoma protein (pRb), fascin-1, estrogen receptor-β, CD117, osteopontin, hypoxia-inducible factor-1α, and cyclooxygenase-2. The binary logistic regression method was used to generate functions that discriminate between benign and borderline PT and also between FA and benign PT.

RESULTS

On the basis of the most active area of stained stromal cells, the staining intensity, and the immunoscore, the expression of Ki-67, topoisomerase IIα, p16, and pRb was significantly higher in borderline or malignant PTs than in benign PTs. Ki-67 could discriminate benign from borderline PTs singly with a high sensitivity (91.7%), specificity (100%), and accuracy (98%). In addition, expression of Ki-67, p16, and pRb was significantly higher in benign PT than in FA. Binary logistic regression identified p16 and pRb as the only marker combination capable of distinguishing FA from benign PTs with sensitivity (94.7%), specificity (75%), and accuracy (87.9%).

CONCLUSION

Ki-67 may be a useful marker for discriminating benign from borderline PTs, and p16 and pRb may be a useful combination of markers for distinguishing FA from benign PTs in core biopsy specimen.

Syndecan-1 modulates the motility and resolution responses of macrophages

OBJECTIVE

Syndecan-1 (Sdc-1) is a member of a family of cell surface proteoglycans, which has been reported to participate in the regulation of events relevant to tissue repair and chronic injury responses, including cell-substrate interactions, matrix remodeling, and cell migration. In this study, we report the functional significance of Sdc-1 in polarized macrophage populations and its role in adhesion and motility events relevant to resolution of the inflammatory program.

APPROACH AND RESULTS

Macrophage Sdc-1 expression is associated with differentiated M2 macrophages with high intrinsic motility, and Sdc-1 deficiency is characterized by impaired migration and enhanced adhesion. Leukocyte infiltration and emigration were examined in a thioglycollate-induced model of peritonitis in Sdc-1(+/+) and Sdc-1(-/-) mice. Although the infiltration of inflammatory cells was similar in both cohorts, a significant delay in the lymphatic clearance of Sdc-1(-/-) macrophages was observed. Moreover, we observed enhanced inflammation and greater burden of atherosclerotic plaques in ApoE(-/-)Sdc-1(-/-) mice maintained on a Western diet.

CONCLUSIONS

These results demonstrate that defective motility in Sdc-1(-/-) macrophages promotes a persistent inflammatory state with relevance to the pathogenesis of atherosclerosis.

The tumor marker Fascin is induced by the Epstein-Barr virus-encoded oncoprotein LMP1 via NF-κB in lymphocytes and contributes to their invasive migration

Background

The actin-bundling protein Fascin (FSCN1) is a tumor marker that is highly expressed in numerous types of cancer including lymphomas and is important for migration and metastasis of tumor cells. Fascin has also been detected in B lymphocytes that are freshly-infected with Epstein-Barr virus (EBV), however, both the inducers and the mechanisms of Fascin upregulation are still unclear.

Results

Here we show that the EBV-encoded oncoprotein latent membrane protein 1 (LMP1), a potent regulator of cellular signaling and transformation, is sufficient to induce both Fascin mRNA and protein in lymphocytes. Fascin expression is mainly regulated by LMP1 via the C-terminal activation region 2 (CTAR2). Block of canonical NF-κB signaling using a chemical inhibitor of IκB kinase β (IKKβ) or cotransfection of a dominant-negative inhibitor of IκBα (NFKBIA) reduced not only expression of p100, a classical target of the canonical NF-κB-pathway, but also LMP1-induced Fascin expression. Furthermore, chemical inhibition of IKKβ reduced both Fascin mRNA and protein levels in EBV-transformed lymphoblastoid cell lines, indicating that canonical NF-κB signaling is required for LMP1-mediated regulation of Fascin both in transfected and transformed lymphocytes. Beyond that, chemical inhibition of IKKβ significantly reduced invasive migration of EBV-transformed lymphoblastoid cells through extracellular matrix. Transient transfection experiments revealed that Fascin contributed to LMP1-mediated enhancement of invasive migration through extracellular matrix. While LMP1 enhanced the number of invaded cells, functional knockdown of Fascin by two different small hairpin RNAs resulted in significant reduction of invaded, non-attached cells.

Conclusions

Thus, our data show that LMP1-mediated upregulation of Fascin depends on NF-κB and both NF-κB and Fascin contribute to invasive migration of LMP1-expressing lymphocytes.

Fascin upregulation in primary head and neck squamous cell carcinoma is associated with lymphatic metastasis

Fascin is an actin-bundling protein that is associated with cellular motility and cancer-cell invasion. The present study aimed to examine the expression of fascin in head and neck squamous cell carcinoma (HNSCC) and its potential use as a biomarker. In a prospective study with a median follow-up time of 48.8 months, tumor tissues, adjacent healthy tissues and cervical lymph node metastases were collected from 25 patients and analyzed by immunohistochemistry. The specimens were scored according to the intensity of fascin staining and the percentage of tumor cells stained using a semi-quantitative scoring approach; the data were analyzed and correlated with clinical follow-up observations. All of the investigators were blinded to the origin of the specimens. The expression levels of fascin were significantly increased in the tumor tissues (P=0.03) and lymph node metastases (P=0.03) compared with that of the normal tissues. The high expression level of fascin in the tumor tissues was correlated with the N-status, however, not with overall survival. Therefore, fascin may be a suitable marker for the prediction of regional lymphatic metastasis in HNSCC.

Fascin 1 is dispensable for developmental and tumour angiogenesis

The actin bundling protein fascin 1 is not expressed in adult epithelial tissues, but during development it is transiently expressed in many different cell types, and later in adults it is expressed in a subset of immune cells, nervous tissues, endothelial cells, smooth muscle cells and pericytes. In contrast to the wealth of knowledge about the role of fascin 1 in cancer cell migration and invasion, little is known about the involvement of fascin 1 in angiogenesis. We speculated that as angiogenesis involves migration and invasion of tissues by endothelial cells, fascin 1 might have a role in both normal and tumour angiogenesis. Here, we provide evidence that loss of fascin 1 causes relatively minor reductions to angiogenesis during embryonic, postnatal and cancerous development by examining E12.5 hindbrains, postnatal retinas and B16F0 tumour cell allografts in fascin 1-null mice. We also find that in fascin 1 null tissues, endothelial cells display reduced filopodia formation during sprouting. We thus propose that fascin 1 expression promotes angiogenesis via filopodia formation, but is largely dispensable for both normal and tumour angiogenesis.

The correlation of cortactin and fascin-1 expression with clinicopathological parameters in pancreatic and ampulla of Vater adenocarcinoma

Cortactin and fascin-1 are important factors affecting progression and metastasis of carcinomas. We tested the hypothesis that cortactin and fascin expression has significant correlation with clinicopathological parameters in pancreatic and ampulla of Vater adenocarcinomas. Immunohistochemical analysis of cortactin and fascin-1 was performed in 50 pancreatic and 40 ampulla of Vater adenocarcinomas. The specimens were from 29 R0, 8 R1, and 13 palliative resections of pancreatic adenocarcinomas and 18 R0, 14 R1, and 8 palliative resections of ampulla of Vater adenocarcinomas. 'R0' resection is defined by complete removal of the tumor and histologically negative surgical margins and 'R1' resection indicates the presence of microscopically residual disease at the surgical margins. The level of expression was assessed by scoring the intensity of cytoplasmic or membranous immunostaining on a 4-point scale. Higher immunostaining scores of cortactin and fascin-1 were both significantly correlated with histological grade, American Joint Committee on Cancer (AJCC) stage, and survival rate in all patients. In conclusion, overexpression of cortactin and fascin-1 implies poorer tumor differentiation, advanced AJCC stage, and shorter survival rate in pancreatic and ampulla of Vater adenocarcinomas.

Tunneling nanotubes provide a unique conduit for intercellular transfer of cellular contents in human malignant pleural mesothelioma

Tunneling nanotubes are long, non-adherent F-actin-based cytoplasmic extensions which connect proximal or distant cells and facilitate intercellular transfer. The identification of nanotubes has been limited to cell lines, and their role in cancer remains unclear. We detected tunneling nanotubes in mesothelioma cell lines and primary human mesothelioma cells. Using a low serum, hyperglycemic, acidic growth medium, we stimulated nanotube formation and bidirectional transfer of vesicles, proteins, and mitochondria between cells. Notably, nanotubes developed between malignant cells or between normal mesothelial cells, but not between malignant and normal cells. Immunofluorescent staining revealed their actin-based assembly and structure. Metformin and an mTor inhibitor, Everolimus, effectively suppressed nanotube formation. Confocal microscopy with 3-dimensional reconstructions of sectioned surgical specimens demonstrated for the first time the presence of nanotubes in human mesothelioma and lung adenocarcinoma tumor specimens. We provide the first evidence of tunneling nanotubes in human primary tumors and cancer cells and propose that these structures play an important role in cancer cell pathogenesis and invasion.

Loss of miR-133a expression associated with poor survival of breast cancer and restoration of miR-133a expression inhibited breast cancer cell growth and invasion

Background

miRNAs, endogenous oligonucleotide RNAs, play an important role in mammary gland carcinogenesis and tumor progression. Detection of their expression and investigation of their functions could lead to discovery of novel biomarkers for breast cancer.

Methods

In situ hybridization was used to detect miR-133a expression in formalin-fixed paraffin-embedded breast surgical specimens from 26 benign, 34 pericancerously normal and 90 cancerous tissues. qRT-PCR was performed to assess miR-133a levels in 6 breast cell lines and 10 benign and 18 cancerous fresh breast tissue specimens. Cell viability, migration, and invasion assays were used to determine the role of miR-133a in regulation of breast cancer cell growth, migration, and invasion, respectively. Luciferase assay was performed to assess miR-133a binding to FSCN1 gene.

Results

Expression of miR-133a was reduced from normal through benign to cancerous breast tissues. Expression of miR-133a was also low in breast cancer cell lines. The reduced miR-133a expression was associated with lymph nodes metastasis, high clinical stages, and shorter relapse-free survivals of patients with breast cancer. Furthermore, transfection of miR-133a oligonucleotides slightly inhibited growth but significantly decreased migration and invasion capacity of breast cancer cells, compared with negative controls, whereas knockdown of miR-133a expression induced breast cancer cell migration and invasion. In addition, we identified a putative miR-133a binding site in the 3'-untranslated region (UTR) of Fascin1 (FSCN1) gene using an online bioinformatical tool. We found that miR-133a transfection significantly reduced expression of FSCN1 mRNA and protein. The luciferase reporter assay confirmed that FSCN1 was the direct target gene of miR-133a.

Conclusions

miR-133a expression was lost in breast cancer tissues, loss of which was associated with lymph nodes metastasis, high clinical stages and shorter relapse-free survivals of patients with breast cancer. Functionally, miR-133a can suppress tumor cell invasion and migration and targeted the expression of FSCN1. Future study will verify whether detection of miR-133a expression can served as a novel biomarker for breast cancer progression and patient prognosis.

The filopodium: a stable structure with highly regulated repetitive cycles of elongation and persistence depending on the actin cross-linker fascin

The ability of mammalian cells to adhere and to migrate is an essential prerequisite to form higher organisms. Early migratory events include substrate sensing, adhesion formation, actin bundle assembly and force generation. Latest research revealed that filopodia are important not only for sensing the substrate but for all of the aforementioned highly regulated processes. However, the exact regulatory mechanisms are still barely understood. Here, we demonstrate that filopodia of human keratinocytes exhibit distinct cycles of repetitive elongation and persistence. A single filopodium thereby is able to initiate the formation of several stable adhesions. Every single filopodial cycle is characterized by an elongation phase, followed by a stabilization time and in many cases a persistence phase. The whole process is strongly connected to the velocity of the lamellipodial leading edge, characterized by a similar phase behavior with a slight time shift compared to filopodia and a different velocity. Most importantly, re-growth of existing filopodia is induced at a sharply defined distance between the filopodial tip and the lamellipodial leading edge. On the molecular level this re-growth is preceded by a strong filopodial reduction of the actin bundling protein fascin. This reduction is achieved by a switch to actin polymerization without fascin incorporation at the filopodial tip and therefore subsequent out-transport of the cross-linker by actin retrograde flow.

Fascin promotes the motility and invasiveness of pancreatic cancer cells

AIM: To explore the role of actin-bundling protein, fascin during the progression of pancreatic cancer.

METHODS: The plasmid expressing human fascin-1 was stably transfected into the pancreatic cancer cell line MIA PaCa-2. The proliferation, cell cycle, motility, scattering, invasiveness and organization of the actin filament system in fascin-transfected MIA PaCa-2 cells and control non-transfected cells were determined.

RESULTS: Heterogeneous overexpression of fascin markedly enhanced the motility, scattering, and invasiveness of MIA PaCa-2 cells. However, overexpression of fascin had minimal effect on MIA PaCa-2 cell proliferation and cell cycle. In addition, cell morphology and organization of the actin filament system were distinctly altered in fascin overexpressed cells. When transplanted into BALB/c-nu mice, fascin-transfected pancreatic cancer cells developed solid tumors at a slightly slower rate, but these tumors displayed more aggressive behavior in comparison with control tumors.

CONCLUSION: Fascin promotes pancreatic cancer cell migration, invasion and scattering, thus contributes to the aggressive behavior of pancreatic cancer cells.

The tumor marker Fascin is strongly induced by the Tax oncoprotein of HTLV-1 through NF-κB signals

Oncogenic transformation of CD4+ T cells by human T-cell lymphotropic virus type 1 (HTLV-1) is understood as the initial step to adult T-cell leukemia/lymphoma, a process that is mainly initiated by perturbation of cellular signaling by the viral Tax oncoprotein, a potent transcriptional regulator. In search of novel biomarkers with relevance to oncogenesis, we identified the tumor marker and actin-bundling protein Fascin (FSCN1) to be specifically and strongly up-regulated in both HTLV-1–transformed and adult T-cell leukemia/lymphoma patient-derived CD4+ T cells. Fascin is important for migration and metastasis in various types of cancer. Here we report that a direct link can exist between a single viral oncoprotein and Fascin expression, as the viral oncoprotein Tax was sufficient to induce high levels of Fascin. Nuclear factor-κB signals were important for Tax-mediated transcriptional regulation of Fascin in T cells. This suggests that Fascin up-regulation by Tax contributes to the development of HTLV-1–associated pathogenesis.

The association of genomic variation of Epstein-Barr virus BamHI F fragment with the proliferation of nasopharyngeal carcinoma

To investigate the f variant of Epstein-Barr virus (EBV) in nasopharyngeal carcinogenesis, we detected the f variant in primary nasopharyngeal carcinoma (NPC), metastatic carcinoma of the lymph node (LN), and chronic inflammation of the nasopharynx from the Guangdong region. Meanwhile, we analyzed the relationship between the f variant of EBV and LMP1, Fascin, pStat3, p53, Bcl-2, and Ki-67 expression in NPC. The results showed that the f variant of EBV was found in 11 cases of primary NPCs with LN metastasis, 12 LN metastases, and 18 primary NPCs without LN metastasis. However, only one demonstrated the F/f variant in 50 cases of chronic inflammation of the nasopharynx. The expression rate of LMP1, Fascin, pStat3, p53, Bcl-2, and Ki-67 in NPC with the f or F/f variant was higher than that with the F prototype. Furthermore, there was a significantly positive correlation between the f variant of EBV and Ki-67 expression (p < 0.05). Our study suggests that the f variant of EBV may be closely related to nasopharyngeal carcinogenesis.

Multidimensional degradomics identifies systemic autoantigens and intracellular matrix proteins as novel gelatinase B/MMP-9 substrates

The action radius of matrix metalloproteinases or MMPs is not restricted to massive extracellular matrix (ECM) degradation, it extends to the proteolysis of numerous secreted and membrane-bound proteins. Although many instances exist in which cells disintegrate, often in conjunction with induction of MMPs, the intracellular MMP substrate repertoire or degradome remains relatively unexplored. We started an unbiased exploration of the proteolytic modification of intracellular proteins by MMPs, using gelatinase B/MMP-9 as a model enzyme. To this end, multidimensional degradomics technology was developed by the integration of broadly available biotechniques. In this way, 100-200 MMP-9 candidate substrates were isolated, of which 69 were identified. Integration of these results with the known biological functions of the substrates revealed many novel MMP-9 substrates from the intracellular matrix (ICM), such as actin, tubulin, gelsolin, moesin, ezrin, Arp2/3 complex subunits, filamin B and stathmin. About 2/3 of the identified candidates were autoantigens described in multiple autoimmune conditions and in cancer (e.g. annexin I, nucleolin, citrate synthase, HMGB1, alpha-enolase, histidyl-tRNA synthetase, HSP27, HSC70, HSP90, snRNP D3). These findings led to the insight that MMPs and other proteases may have novel (immuno)regulatory properties by the clearance of toxic and immunogenic burdens of abundant ICM proteins released after extensive necrosis. In line with the extracellular processing of organ-specific autoantigens, proteolysis might also assist in the generation of immunodominant 'neo-epitopes' from systemic autoantigens. The study of proteolysis of ICM molecules, autoantigens, alarmins and other crucial intracellular molecules may result in the discovery of novel roles for proteolytic modification.

The expression of six biomarkers in the four most common ovarian cancers: correlation with clinicopathological parameters

This study aimed to evaluate the relationship of fascin-1, matrix metalloproteinase (MMP)-2, MMP-9, cortactin, survivin, and epidermal growth factor receptor (EGFR) expression with clinicopathological parameters for the four most common ovarian surface epithelial carcinomas. Six biomarkers were investigated immunohistochemically using tissue microarrays of 185 specimens including 79 serous cystadenocarcinomas, 47 mucinous cystadenocarcinomas, 45 endometrioid adenocarcinomas, and 14 clear cell carcinomas. The four most common ovarian carcinomas showed significant expression of fascin-1, cortactin, survivin, and EGFR, but not of MMP-2 and MMP-9. In addition, higher immunostaining scores for fascin-1 in mucinous cystadenocarcinomas correlated with T stage, N stage, American Joint Committee on Cancer AJCC clinical stage, and a poorer survival rate; for cortactin in serous cystadenocarcinomas correlated with T stage; for cortactin in clear cell carcinomas correlated with T and clinical AJCC stages; and for survivin in clear cell carcinomas correlated with T stage and AJCC clinical stage. In addition, higher immunostaining scores for fascin-1, cortactin, and survivin correlated with poorer tumor differentiation in serous, mucinous, and endometrioid adenocarcinomas. Thus, the expression of fascin-1, cortactin, and survivin may be helpful in evaluating the aggressiveness of ovarian mucinous, serous, and clear cell adenocarcinoma. Additionally, the expression of fascin-1 may be an independent prognostic risk factor in mucinous cystadenocarcinoma.

Recurrence of pleomorphic adenoma of the parotid gland--predictive value of cadherin-11 and fascin

The predictive value of cadherin-11, tenascin, fascin, and mucin-1 as markers for the likelihood of recurrence in pleomorphic adenoma of the parotid gland was examined. In this retrospective study we analysed 20 tumours from16 patients by immunohistochemistry. Staining intensities were measured using a semiquantitative scoring approach; localisation (tumour centre vs border) as well as clinical data were analysed and correlated with follow-up. Cadherin-11 was increased in recurrent tumours. However, no changes of fascin, tenascin or mucin-1 were observed. Cadherin-11 and fascin were increased in primary tumours of patients with later recurrence, with fascin upregulation restricted to the tumour border. In conclusion, cadherin-11 and fascin should be further analysed for their value as markers for later recurrence in pleomorphic adenoma. Our observations might reflect dysregulation of cellular pathways contributing to cellular dissemination, which might potentially result in later recurrence.

Immunolocalization of fascin, an actin-bundling protein and glial fibrillary acidic protein in human astrocytoma cells

Fascin is a 55-kDa globular protein that functions to organize filamentous-actin into parallel bundles. A role for fascin in cell migration has led to its study in many tumor types. In this report, we investigate fascin in astrocytomas. We show that fascin is expressed in astrocytes and in a panel of human astrocytoma cell lines. Immunofluorescence analysis demonstrates that fascin and the intermediate filament protein, glial fibrillary acidic protein (GFAP), are both expressed in the perinuclear region and within cytoplasmic processes of astrocytes and astrocytoma cells. Amino acid residues within the NH2 terminus of GFAP can undergo phosphorylation; these modifications regulate intermediate filament disassembly and occur during cytokinesis. We show that fascin and specific phosphorylated species of GFAP colocalize within dividing cells. Finally, we demonstrate that fascin co-immunoprecipitates with GFAP and that immunocomplex formation is preferential for GFAP phosphorylated at serine residues 8 and 13. These data show that fascin and GFAP are immunolocalized regionally within cells and tumors of astrocytic origin and suggest that their binding may occur during dynamic reorganization of intermediate filaments.

Cell biology of embryonic migration

Cell migration is an evolutionarily conserved mechanism that underlies the development and functioning of uni- and multicellular organisms and takes place in normal and pathogenic processes, including various events of embryogenesis, wound healing, immune response, cancer metastases, and angiogenesis. Despite the differences in the cell types that take part in different migratory events, it is believed that all of these migrations occur by similar molecular mechanisms, whose major components have been functionally conserved in evolution and whose perturbation leads to severe developmental defects. These mechanisms involve intricate cytoskeleton-based molecular machines that can sense the environment, respond to signals, and modulate the entire cell behavior. A big question that has concerned the researchers for decades relates to the coordination of cell migration in situ and its relation to the intracellular aspects of the cell migratory mechanisms. Traditionally, this question has been addressed by researchers that considered the intra- and extracellular mechanisms driving migration in separate sets of studies. As more data accumulate researchers are now able to integrate all of the available information and consider the intracellular mechanisms of cell migration in the context of the developing organisms that contain additional levels of complexity provided by extracellular regulation. This review provides a broad summary of the existing and emerging data in the cell and developmental biology fields regarding cell migration during development.

Proteomic analysis to characterize differential mouse strain sensitivity to cadmium-induced forelimb teratogenesis

BACKGROUND

Cadmium ion (Cd2+) is a ubiquitous environmental contaminant, and it is a potent teratogen in mice. An intraperitoneal dose of 4 mg/kg of CdCl2 at gestational day 9 causes forelimb ectrodactyly in the C57BL/6N mouse strain, but the SWV/Fnn strain is resistant. The objective of this study was to identify differentially displayed proteins in two target tissues for cadmium teratogenesis, and to derive hypotheses regarding the mechanisms involved in the murine strain difference in Cd-induced forelimb ectrodactyly.

METHODS

The global proteomics strategy used two-dimensional polyacrylamide gel electrophoresis for protein separation, and MALDI-TOF-MS and LC-MS/MS for protein identification, to compare and identify proteins in forelimb buds and yolk sacs from the two mouse strains following Cd administration.

RESULTS

More than 1,000 protein spots were detected by two-dimensional polyacrylamide gel electrophoresis in day 10.0 mouse forelimb buds and yolk sacs. Thirty-eight proteins had identifiable differences in abundance levels in Cd-treated forelimb buds between the two strains. Of those 38 proteins, 14 could be associated with the unfolded protein response process and seven are associated with actin polymerization. The proteins that were found to be differentially abundant between the strains in yolk sacs that were exposed to CdCl2 were predominantly different than the proteins detected differentially in the limb buds of the two strains with an overlap of approximately 20%.

CONCLUSIONS

These patterns of differentially displayed proteins rationalize a hypothesis that the differential murine strain response to cadmium-induced forelimb ectrodactyly is due to differences in their pathways for the unfolded protein response and/or actin polymerization.

Photorhabdus luminescens genes induced upon insect infection

BACKGROUND

Photorhabdus luminescens is a Gram-negative luminescent enterobacterium and a symbiote to soil nematodes belonging to the species Heterorhabditis bacteriophora. P.luminescens is simultaneously highly pathogenic to insects. This bacterium exhibits a complex life cycle, including one symbiotic stage characterized by colonization of the upper nematode gut, and a pathogenic stage, characterized by release from the nematode into the hemocoel of insect larvae, resulting in rapid insect death caused by bacterial toxins. P. luminescens appears to sense and adapt to the novel host environment upon changing hosts, which facilitates the production of factors involved in survival within the host, host-killing, and -exploitation.

RESULTS

A differential fluorescence induction (DFI) approach was applied to identify genes that are up-regulated in the bacterium after infection of the insect host Galleria mellonella. For this purpose, a P. luminescens promoter-trap library utilizing the mCherry fluorophore as a reporter was constructed, and approximately 13,000 clones were screened for fluorescence induction in the presence of a G. mellonella larvae homogenate. Since P. luminescens has a variety of regulators that potentially sense chemical molecules, like hormones, the screen for up-regulated genes or operons was performed in vitro, excluding physicochemical signals like oxygen, temperature or osmolarity as variables. Clones (18) were obtained exhibiting at least 2.5-fold induced fluorescence and regarded as specific responders to insect homogenate. In combination with a bioinformatics approach, sequence motifs were identified in these DNA-fragments that are similar to 29 different promoters within the P. luminescens genome. By cloning each of the predicted promoters upstream of the reporter gene, induction was verified for 27 promoters in vitro, and for 24 promoters in viable G. mellonella larvae. Among the validated promoters are some known to regulate the expression of toxin genes, including tccC1 (encoding an insecticidal toxin complex), and others encoding putative toxins. A comparably high number of metabolic genes or operons were observed to be induced upon infection; among these were eutABC, hutUH, and agaZSVCD, which encode proteins involved in ethanolamine, histidine and tagatose degradation, respectively. The results reflect rearrangements in metabolism and the use of other metabolites available from the insect. Furthermore, enhanced activity of promoters controlling the expression of genes encoding enzymes linked to antibiotic production and/or resistance was observed. Antibiotic production and resistance may influence competition with other bacteria, and thus might be important for a successful infection. Lastly, several genes of unknown function were identified that may represent novel pathogenicity factors.

CONCLUSION

We show that a DFI screen is useful for identifying genes or operons induced by chemical stimuli, such as diluted insect homogenate. A bioinformatics comparison of motifs similar to known promoters is a powerful tool for identifying regulated genes or operons. We conclude that signals for the regulation of those genes or operons induced in P. luminescens upon insect infection may represent a wide variety of compounds that make up the insect host. Our results provide insight into the complex response to the host that occurs in a bacterial pathogen, particularly reflecting the potential for metabolic shifts and other specific changes associated with virulence.

Expression of fascin in thyroid neoplasms: a novel diagnostic marker

PURPOSE

Fascin, an actin-bundling protein, is markedly upregulated in several epithelial tumors and its expression often correlates with high-grade, extensive invasion, and distant metastasis. However, reports about fascin expression in endocrine tumors remain rare. The aim of the present study was to assess the diagnostic significance of fascin in thyroid neoplasms.

METHODS

Thyroid samples from 177 cases were examined for fascin and Ki-67 expression by immunohistochemistry.

RESULTS

Fascin immunoreactivity was negative in normal follicles and nodular goiter. Fascin immunostaining was positive in 62.1% (41/66) of thyroid carcinomas and 26.4% (19/72) of thyroid adenomas; the difference being significant (P < 0.0001). In thyroid papillary carcinoma, upregulation of fascin was associated with both the Ki-67 labeling index and the occurrence of lymph node metastasis.

CONCLUSION

Fascin may be a novel marker to distinguish thyroid carcinoma from benign lesions and may be involved in the proliferation and metastasis of papillary carcinoma.

Association of cortactin and fascin-1 expression in gastric adenocarcinoma: correlation with clinicopathological parameters

Cortactin and fascin-1 are important factors in tumor progression. We tested the hypothesis that cortactin and fascin-1 expression correlates with clinicopathological parameters of gastric adenocarcinoma. Immunohistochemical analysis of cortactin and fascin-1 was done using tissue microarrays of 100 surgical specimens, including 20 well-differentiated, 20 moderately differentiated, and 60 poorly differentiated gastric adenocarcinomas. Among the 20 well-differentiated gastric adenocarcinomas, 15 cases (75%) showed negative or weak staining (1+); 5 cases (25%) had moderate (2+) or strong (3+) cortactin expression. Among the 60 poorly differentiated gastric adenocarcinomas, more than three-quarters of the cases (76.7%) had moderate or strong cortactin expression; 14 cases (23.3%) had weak staining. Of 20 well-differentiated gastric adenocarcinoma cases, 14 (70%) showed negative or weak staining of fascin-1, whereas nearly one-third (30%) had moderate or strong expression. Among the 60 poorly differentiated gastric adenocarcinomas, 32 (53.3%) exhibited moderate or strong fascin-1 expression; fewer than half of the cases showed negative or weak staining. Higher intensity of cortactin and fascin-1 staining correlated directly with more-advanced cancer stages (TNM) and inversely with survival rates. Our findings suggest the possibility that pharmacological inhibitors of cortactin and fascin-1 activity may slow down tumor progression and prolong survival time in patients with gastric adenocarcinomas.

Proteomic identification of brain proteins in the canine model of human aging following a long-term treatment with antioxidants and a program of behavioral enrichment: relevance to Alzheimer's disease

Aging and age-related disorders such as Alzheimer's disease (AD) are usually accompanied by oxidative stress as one of the main mechanisms contributing to neurodegeneration and cognitive decline. Aging canines develop cognitive dysfunction and neuropathology similar to those seen in humans, and the use of antioxidants results in reductions in oxidative damage and in improvement in cognitive function in this canine model of human aging. In the present study, the effect of a long-term treatment with an antioxidant-fortified diet and a program of behavioral enrichment on oxidative damage was studied in aged canines. To identify the neurobiological mechanisms underlying these treatment effects, the parietal cortex from 23 beagle dogs (8.1-12.4 years) were treated for 2.8 years in one of four treatment groups: i.e., control food-control behavioral enrichment (CC); control food-behavioral enrichment (CE); antioxidant food-control behavioral enrichment (CA); enriched environment-antioxidant-fortified food (EA). We analyzed the levels of the oxidative stress biomarkers, i.e., protein carbonyls, 3-nitrotyrosine (3-NT), and the lipid peroxidation product, 4-hydroxynonenal (HNE), and observed a decrease in their levels on all treatments when compared to control, with the most significant effects found in the combined treatment, EA. Since EA treatment was most effective, we also carried out a comparative proteomics study to identify specific brain proteins that were differentially expressed and used a parallel redox proteomics approach to identify specific brain proteins that were less oxidized following EA. The specific protein carbonyl levels of glutamate dehydrogenase [NAD (P)], glyceraldehyde-3-phosphate dehydrogenase (GAPDH), alpha-enolase, neurofilament triplet L protein, glutathione-S-transferase (GST) and fascin actin bundling protein were significantly reduced in brain of EA-treated dogs compared to control. We also observed significant increases in expression of Cu/Zn superoxide dismutase, fructose-bisphosphate aldolase C, creatine kinase, glutamate dehydrogenase and glyceraldehyde-3-phosphate dehydrogenase. The increased expression of these proteins and in particular Cu/Zn SOD correlated with improved cognitive function. In addition, there was a significant increase in the enzymatic activities of glutathione-S-transferase (GST) and total superoxide dismutase (SOD), and significant increase in the protein levels of heme oxygenase (HO-1) in EA treated dogs compared to control. These findings suggest that the combined treatment reduces the levels of oxidative damage and improves the antioxidant reserve systems in the aging canine brain, and may contribute to improvements in learning and memory. These observations provide insights into a possible neurobiological mechanism underlying the effects of the combined treatment. These results support the combination treatments as a possible therapeutic approach that could be translated to the aging human population who are at risk for age-related neurodegenerative disorders, including Alzheimer's disease.

Association of EMMPRIN and fascin expression in renal cell carcinoma: correlation with clinicopathological parameters

EMMPRIN and fascin are important factors in tumor invasion and progression. We tested the hypothesis that expression of EMMPRIN and fascin correlate with clinicopathological parameters of renal cell carcinoma (RCC). Immunohistochemical analysis of EMMPRIN and fascin were performed in tissue microarrays of 100 surgical specimens, including 35 clear-cell RCC (CRCC), 21 clear-cell RCC with granular differentiation (GRCC), 12 chromophobe RCC (ChRCC), 8 papillary RCC (PRCC), 9 carcinoma of the collecting duct of Bellini (CDC), 10 clear-cell RCC with sarcomatoid differentiation (SRCC), and 6 metastatic RCC. Average immunoscores of EMMPRIN were 100.8 in CRCC, 195.2 in GRCC, 298.4 in ChRCC, 219.2 in PRCC, 186.1 in CDC, 226.9 in SRCC, and 151.7 in metastatic RCC. Among all included cases, average EMMPRIN immunoscores were 84.6 in grade I, 130.4 in grade II, 184.3 in grade III, and 223.5 in grade IV. Additionally, average immunostaining scores of fascin were 53.6 in CRCC, 289.3 in GRCC, 193.3 in ChRCC, 151.8 in PRCC, 181.3 in CDC, 275.4 in SRCC, and 131.7 in metastatic RCC. Average fascin immunoscores were 59.3 in grade I, 91.6 in grade II, 130.2 in grade III, and 194.7 in grade IV. Higher EMMPRIN and fascin immunoscores also correlated significantly with TNM stages and survival rates in RCC. Significant correlation was found between EMMPRIN and fascin expression. In conclusion, higher expression of EMMPRIN and fascin correlate significantly with histological grades, clinical stages, and survival rates of RCC.

Inhibition of the α-mannosidase Man2c1 gene expression enhances adhesion of Jurkat cells

Protein N-glycosylation plays very important roles in immunity and alpha-mannosidase is one of the key enzymes in N-glycosylation. This paper reports that inhibition of alpha-mannosidase Man2c1 gene expression enhances adhesion of Jurkat T cells. In comparison to the controls with normal expression of the enzyme, Jurkat cells with the inhibition of Man2c1 gene expression (AS cell) formed larger aggregates in culture, indicating an enhancement of adhesion between the cells. mRNA differential display analysis discovered up-regulation of several adhesion molecule genes in the AS cell. Because of the pivotal role played by CD54-LFA-1 interaction in immune cell interaction, this study focused on the contribution of enhanced expression of CD54 and LFA-1 to the enhanced adhesion of AS Jurkat cells. These facts, including increased binding of AS cells to ICAM-1-Fc, Mg(2+) activation of the binding of AS cells to ICAM-1-Fc and enhanced aggregation of AS cells, together with the inhibiting effect of a blocking CD11a mAb on the binding to ICAM-1-Fc and aggregation of the cells demonstrate an important contribution of enhanced CD54-LFA-1 interaction to increased adhesion between AS cells. The enhanced CD54-LFA-1 interaction also resulted in increased adhesion between AS Jurkat T cells and Raji B cells. In addition, AS cells showed cytoskeletal rearrangement. The data imply a biological significance of MAN2C1 in T-cell functioning.

Energetics and dynamics of constrained actin filament bundling

The formation of filopodia-like bundles from a dendritic actin network has been observed to occur in vitro as a result of branching induced by Arp2/3 complex. We study both the energetics and dynamics of actin filament bundling in such a network to evaluate their relative importance in bundle formation processes. Our model considers two semiflexible actin filaments fixed at one end and free at the other, described using a normal-mode approximation. This model is studied by both Brownian dynamics and free-energy minimization methods. Remarkably, even short filaments can bundle at separations comparable to their lengths. In the dynamic simulations, we evaluate the time required for the filaments to interact and bind, and examine the dependence of this bundling time on the filament length, the distance between the filament bases, and the cross-linking energy. In most cases, bundling occurs in a second or less. Beyond a certain critical distance, we find that the bundling time increases very rapidly with increasing interfilament separation and/or decreasing filament length. For most of the cases we have studied, the energetics results for this critical distance are similar to those obtained from dynamics simulations run for 10 s, suggesting that beyond this timescale, energetics, rather than kinetic constraints, determine whether or not bundling occurs. Over a broad range of conditions, we find that the times required for bundling from a network are compatible with experimental observations.

Fascin is a potential biomarker for early-stage oesophageal squamous cell carcinoma

BACKGROUND

Fascin, an actin-binding protein, is usually expressed at a low level in normal epithelium, but is markedly up regulated in several types of carcinomas. Reports on fascin expression in oesophageal squamous cell carcinoma (ESCC) and precancerous lesions remain rare.

AIM

To show the roles of fascin in the progression from normal epithelium to invasive ESCC.

METHODS

Fascin expression in 102 sections embedded in paraffin wax, including samples of normal mucosa (n = 20), dysplasia (n = 10), ESCC (n = 62) and special sections (n = 10) of a full-length mucosa layer from the distant margin to the cancer focus of the excised oesophagus, and 49 fresh specimens of ESCC was analysed by immunohistochemistry, western blot and real-time reverse transcription-polymerase chain reaction. Fascin expression in ESCC cell lines was also investigated.

RESULTS

In the immunohistochemical study, the positive rate of fascin was significantly higher in the tumour tissue than in the normal epithelium (p = 0.020), but no significant difference was shown between ESCC and dysplasia (p = 1.000). Immunostaining for fascin was only apparent in the basal layer of the normal epithelium. However, in the dysplasia, positive staining was observed in most of the heterogeneous cells from the basal layer to the granular layer of the epithelium. Fascin expression was seen to increase progressively from the normal epithelium to invasive ESCC. Up regulation of fascin was observed in 87.76% (43/49) and 77.55% (38/49) of the specimens, respectively, using western blot and real-time reverse transcription-polymerase chain reaction assays; 80% (4/5) of ESCC cell lines also expressed fascin at a high level. Furthermore, overexpression of fascin was markedly correlated with cell proliferation and lymph node metastasis.

CONCLUSIONS

These findings suggested that fascin was associated with the transformation and development of ESCC and implicated the potential of fascin as a novel biomarker that would allow the tumour to be identified at an early stage in high-risk individuals.

Fascin expression in 90 patients with glioblastoma multiforme

Fascin is a protein that serves to aggregate F actin into bundles that rearrange the cytoskeleton and promote cellular motility. Fascin has been linked to the invasive behavior of some tumors. Fascin immunohistochemical analysis was performed in 90 glioblastoma multiforme, including 53 males and 37 females (mean age, 58.3 years). All patients had tumors that demonstrated positive fascin staining. Nineteen tumors showed more than 75% positive staining tumor cells, 14 tumors had more than 50% to 75% staining, 23 tumors had more than 25% to 50% staining, 26 tumors had more than 5% to 25% staining, and 8 tumors had less than 5% staining. In comparison, 9 of 11 low-grade astrocytomas had 50% or less staining for fascin. Eight of 10 anaplastic astrocytomas had more than 50% fascin staining. All gliomas studied expressed fascin by immunohistochemistry. Higher grade tumors generally expressed a greater degree of fascin staining. There was no obvious correlation with the extent of staining and survival among glioblastoma multiforme. Fascin may play a role in tumor cell infiltration.