LYAR promotes colorectal cancer progression by up-regulating FSCN1 expression and is closely related to fatty acid metabolism
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ABSTRACT: Colorectal cancer (CRC) is a highly malignant tumor associated with a poor prognosis, yet the molecular mechanisms are not fully understood. In this study, we showed that LYAR expresses at a higher level in CRC than normal tissue and LYAR expression is closely associated with distant CRC metastasis. LYAR significantly promotes the migration and invasion of CRC cells in vitro, and reduction of LYAR expression in CRC cells inhibites xenograft tumor metastasis in vivo. Microarray analysis of LYAR knockdown (KD) cells combined with ChIP assay, gene reporter assay and rescue experiment indicate that FSCN1 (fascin actin-bundling protein 1, Fascin-1) serves as a new and key regulator of the LYAR-promoted migration and invasion of CRC cells. In addition, knockdown of FSCN1 significantly inhibites subcutaneous tumorigenesis of CRC cells. Moreover, we found that FSCN1 affects some key enzymes in lipid fatty acid metabolism such as FASN and SCD. In summary, this study reveals a novel mechanism by which LYAR promotes tumor cell migration and invasion by up-regulating FSCN1 expression and further promoting fatty acid synthesis in CRC.
Project description:Colorectal cancer (CRC) is a highly malignant tumor associated with poor prognosis, yet the molecular mechanisms are not fully understood. In this study, we showed that LYAR, a nucleolar protein, expresses at a higher level in CRC than adjacent normal tissue and LYAR expression is closely associated with distant CRC metastasis. LYAR not only significantly promotes the migration and invasion of CRC cells in vitro, also the knockdown (KD) of LYAR in CRC cells inhibits xenograft tumor metastasis in vivo. Microarray analysis of LYAR KD cells combined with ChIP assay, gene reporter assay and rescue experiment indicate that FSCN1 (encoding fascin actin-bundling protein 1, Fascin-1) serves as a new key regulator of the LYAR-promoted migration and invasion of CRC cells. Knockdown of FSCN1 significantly inhibits subcutaneous tumorigenesis of CRC cells, and leads to the down-regulation of FASN and SCD, genes encoding key enzymes in fatty acid synthesis. In summary, this study reveals a novel mechanism by which LYAR promotes tumor cell migration and invasion by up-regulating FSCN1 expression and affecting fatty acid metabolism in CRC.
Project description:Fascin actin-bundling protein 1 (FSCN1) is an evolutionarily conserved actin-bundling protein that plays a critical role in cell migration, motility, adhesion and cellular interactions. Although multiple clinical studies have implicated the expression of FSCN1 in laryngeal squamous cell carcinoma (LSCC) progression, the precise mechanism of FSCN1 in the process has not been clearly elucidated. To define FSCN1 function, we characterized FSCN1-interacting proteins in LSCC cells by immunoprecipitation followed by LC-MS/MS. After data filtering, 119 proteins with expression in both the Hep-2 and TU-177 cell samples were identified as FSCN1-interacting partners. With in-depth bioinformatics analysis, we linked FSCN1 to critical cellular processes including cell adhesion, glycolysis/gluconeogenesis, regulation of protein ubiquitination, ribosomal RNA processing and small molecule metabolism. We discuss the interactions between FSCN1 and some of the newly validated partners. The identification of these potential partners of FSCN1 expands our knowledge of the FSCN1 interactome and provides a valuable resource for understanding the functions of this protein in LSCC progression.
Project description:The actin-bundling protein fascin (FSCN1) is overexpressed in aggressive adrenocortical carcinoma (ACC) and represents a reliable prognostic indicator. We investigated the effects of FSCN1 inactivation by CRISPR/Cas9 in ACC H295R cells on global gene expression profiles in those cells. We performed gene expression profiling analysis using data obtained from RNA-seq of 2 different H295R control clones and 2 different FSCN1 KO clones (2 biological replicates for each clone).
Project description:Laryngeal squamous cell carcinoma (LSCC) is a common malignant tumor with a poor prognosis. Fascin actin-bundling protein 1 (FSCN1) has been reported to play a crucial role in LSCC development and progression, but the underlying molecular mechanisms remain unknown. Here, a whole transcriptome microarray analysis was performed to screen for differentially expressed genes in FSCN1 knockdown cells. We identified 1063 differentially expressed mRNA transcripts. Functional annotation revealed that these differentially expressed genes (DEGs) were involved in multiple biological functions such as transcriptional regulation, response to radiation, focal adhesion, ECM-receptor interaction, steroid biosynthesis, and others. Through co-expression and protein-protein interaction analysis, we linked FSCN1 to novel functions, including defense response to virus and steroid biosynthesis.
Project description:Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a high risk of relapse and metastatisation. The actin-bundling protein fascin (FSCN1) is overexpressed in aggressive ACC and represents a reliable prognostic indicator. FSCN1 has been shown to synergize with the Rho/Rac GEF VAV2 in enhancing the invasion properties of ACC cancer cells. Based on those results, we investigated the effects of FSCN1 inactivation by CRISPR/Cas9 or pharmacological blockade on the invasive properties of ACC cells, both in vitro and in an in vivo metastatic ACC zebrafish model. Moreover, to assess the impact of FSCN1 inactivation on global gene and protein expression in H295R cells, we performed RNA-seq and proteomic profiling of control and FSCN1 knock-out (KO) clones.
Project description:Lysine demethylase 7A (KDM7A) catalyzes the removal of dimethylation from histone H3 lysine 9 and lysine 27, both of which are associated with transcription repression. Previous study indicated that Kdm7a mRNA in the medial prefrontal cortex (mPFC) increased after drug exposure, yet its role in drug-related behaviors is largely unknown. In a morphine-conditioned place preference (CPP) paradigm, our findings revealed a specific increase of Kdm7a expression in the mPFC seven days after drug withdrawal. Subsequently, our results demonstrated that knockdown of Kdm7a in the mPFC did not affect the acquisition of morphine-induced CPP, but it attenuated memory consolidation. To further explore Kdm7a-mediated transcriptomic changes, we employed Nanopore direct RNA sequencing. Transcriptome profiling unveiled several gene expression alterations impacted by KDM7A, which were enriched in relevant neural function categories. Notably, we identified and validated fascin actin-bundling protein 1 (Fscn1) as a downstream molecular target. Knockdown of Fscn1 had a similar impact on CPP to Kdm7a, along with a corresponding decrease in dendritic spine density in the mPFC. Additionally, ChIP analysis demonstrated that silencing Kdm7a in N2a cells resulted in decreased enrichment of H3K9me2 and H3K27me2 at the Fscn1 promoter region, suggesting that Kdm7a may act as a crucial regulator of transcriptional responses to morphine-related reward memory via Fscn1.
Project description:Background. High mortality rates are prevalent among patients with non-small cell lung cancer (NSCLC), and effective therapeutic targets are key prognostic factors. Fascin actin-bundling protein 1 (FSCN1) promotes NSCLC; however, its role as an RNA-binding protein in NSCLC remains unexplored. Therefore, we aimed to explore FSCN1 expression and function in A549 cells. Method. We screened for alternative-splicing events and differentially expressed genes (DEGs) after FSCN1 silence via RNA-sequencing (RNA-seq). FSCN1 immunoprecipitation followed by RNA-seq were used to identify target genes whose mRNA expression and pre-mRNA alternative-splicing levels might be influenced by FSCN1. Results. Silencing FSCN1 in A549 cells affected malignant phenotypes; it inhibited proliferation, migration, and invasion, and promoted apoptosis. RNA-seq analysis revealed 2851 DEGs and 3057 alternatively spliced genes. Gene ontology-based functional enrichment analysis showed that downregulated DEGs and alternatively splicing genes were enriched for the cell-cycle. FSCN1 promoted the alternative splicing of cell-cycle-related mRNAs involved in tumorigenesis (i.e., BCCIP, DLGAP5, PRC1, RECQL5, WTAP, and SGO1). Combined analysis of FSCN1 RNA-binding targets and RNA-seq data suggested that FSCN1 might affect ACTG1, KRT7, and PDE3A expression by affecting the pre-mRNA alternative-splicing levels of NME4, NCOR2, and EEF1D FSCN1 to long non-coding RNA transcripts (RNASNHG20, NEAT1, NSD2, and FTH1), which were highly abundant. Overall, extensive transcriptome analysis of gene alternative splicing and expression levels was performed in cells transfected with FSCN1 short-interfering RNA. Our data provide global insights into the regulatory mechanisms mediated by FSCN1 and its target genes in lung cancer.
Project description:Background. High mortality rates are prevalent among patients with non-small cell lung cancer (NSCLC), and effective therapeutic targets are key prognostic factors. Fascin actin-bundling protein 1 (FSCN1) promotes NSCLC; however, its role as an RNA-binding protein in NSCLC remains unexplored. Therefore, we aimed to explore FSCN1 expression and function in A549 cells. Method. We screened for alternative-splicing events and differentially expressed genes (DEGs) after FSCN1 silence via RNA-sequencing (RNA-seq). FSCN1 immunoprecipitation followed by RNA-seq were used to identify target genes whose mRNA expression and pre-mRNA alternative-splicing levels might be influenced by FSCN1. Results. Silencing FSCN1 in A549 cells affected malignant phenotypes; it inhibited proliferation, migration, and invasion, and promoted apoptosis. RNA-seq analysis revealed 2851 DEGs and 3057 alternatively spliced genes. Gene ontology-based functional enrichment analysis showed that downregulated DEGs and alternatively splicing genes were enriched for the cell-cycle. FSCN1 promoted the alternative splicing of cell-cycle-related mRNAs involved in tumorigenesis (i.e., BCCIP, DLGAP5, PRC1, RECQL5, WTAP, and SGO1). Combined analysis of FSCN1 RNA-binding targets and RNA-seq data suggested that FSCN1 might affect ACTG1, KRT7, and PDE3A expression by affecting the pre-mRNA alternative-splicing levels of NME4, NCOR2, and EEF1D FSCN1 to long non-coding RNA transcripts (RNASNHG20, NEAT1, NSD2, and FTH1), which were highly abundant. Overall, extensive transcriptome analysis of gene alternative splicing and expression levels was performed in cells transfected with FSCN1 short-interfering RNA. Our data provide global insights into the regulatory mechanisms mediated by FSCN1 and its target genes in lung cancer.
Project description:<p>Adrenocortical carcinoma (ACC) is a rare endocrine malignancy with a high risk of relapse and metastatisation. The actin-bundling protein fascin (FSCN1) is overexpressed in aggressive ACC and represents a reliable prognostic indicator. FSCN1 has been shown to synergize with the Rho/Rac GEF VAV2 in enhancing the invasion properties of ACC cancer cells. Based on those results, we investigated the effects of FSCN1 inactivation by CRISPR/Cas9 or pharmacological blockade on the invasive properties of ACC cells, both <em>in vitro</em> and in an <em>in vivo</em> metastatic ACC zebrafish model. Here we showed that FSCN1 is a transcriptional target for Beta-catenin in H295R ACC cells and that its inactivation resulted in defects in cell attachment and proliferation. Additionally, FSCN1 knock-out modulated the expression of genes involved in cytoskeleton dynamics and cell adhesion. When SF-1 dosage was upregulated in H95R cells, activating their invasive capacities, FSCN1 knock-out reduced the number of filopodia, lamellipodia/ruffles and focal adhesions, while decreasing cell invasion in Matrigel. Similar effects were produced by the FSCN1 inhibitor G2-044, which also diminished the invasion of ACC cell lines (CU-ACC2, JIL-2266, MUC-1) expressing lower levels of FSCN1 than H295R. In the zebrafish model, metastases formation was significantly reduced in FSCN1 knock-out cells and G2-044 significantly reduced the number of metastases formed by ACC cells. Our results indicate that FSCN1 represents a new druggable target for ACC and provide the rationale for future clinical trials with FSCN1 inhibitors in patients with ACC, possibly in combination with immunotherapy.</p>
Project description:Fascin-1 mediated actin-bundling activity is central to the generation of plasma membrane protrusions required for cell migration. Dysregulation of cellular protrusions is observed in metastatic cancers, where they are required for increased invasiveness, and this is often correlated with overexpression of Fascin-1. Therefore, there is interest in generating therapeutic Fascin-1 inhibitors. We present the identification of Nb 3E11, a nanobody inhibitor of Fascin-1 actin-bundling activity, filopodia formation and cell migration. The crystal structure of the Fascin-1/Nb 3E11 complex reveals the structural mechanism of inhibition. Nb 3E11 occludes an actin-binding site on the third -trefoil domain of Fascin-1 that is currently untargeted by chemical inhibitors and induces a conformational change in the adjacent domains to stabilise Fascin-1 in an inhibitory state similar to that adopted in the presence of small molecule inhibitors. Nb 3E11 can be utilised as a tool inhibitor molecule to aid in the development of Fascin-1 targeted therapeutics.