Project description:Transcriptional dysregulation has emerged as a critical driver of melanoma progression, yet the molecular mechanisms governing this process and their potential as therapeutic targets remain inadequately characterized. Here, we identify FRA1 as a potent and actionable driver of melanoma metastasis. FRA1 enhanced both the initial seeding and subsequent outgrowth of metastatic lesions. Comprehensive multi-omics integration revealed transcriptional target genes of FRA1, with AXL, CDK6, and FSCN1 exhibiting increased expression in melanoma metastasis and a significant correlation with poor patient outcomes. Silencing AXL, CDK6, or FSCN1 abrogated FRA1-mediated invasion in vitro and reduced metastatic colonization. Furthermore, pharmacological inhibition of CDK6 and FSCN1, and to a lesser extent AXL, suppressed melanoma metastasis and prolonged overall survival. The expression of FRA1 and its target genes correlates with shortened survival across multiple cancer types, highlighting the broader clinical relevance of this pathway. This study unveils an actionable FRA1-mediated transcriptional network that drives cancer progression and metastasis, offering potential avenues for therapeutic interventions.
Project description:Application of a melanoma experimental metastasis model to elucidate molecular mediators of melanoma brain metastasis. Malignant melanoma frequently metastasizes to the brain. The molecular mediators of brain metastasis still remains largely unknnown. Two melanoma cell lines (opposing phenotypes in vitro: invasive/proliferative) were injected (L.V) into immune-compromised animals to generate organ-specific in vivo metastatic tumor cells and host tissue. Immunomagnetic separation was applied to separate tumor cells from host stroma. A rat model was applied to generate organ-specific profiles. Subsequently, a mouse model was applied to generate in vivo brain metastatic samples to follow altered gene expression in melanoma colonizing the brain over time. Gene expression data was collected from human and animal host-specific arrays.
Project description:This data is part of a pre-publication release. For information on the proper use of pre-publication data shared by the Wellcome Trust Sanger Institute (including details of any publication moratoria), please see http://www.sanger.ac.uk/datasharing/In this experiment, we have injected mice with fluorescent melanoma cells and then collected their lungs 1-3 days later and run them through a flow cytometer to separate the fluorescent cells (i.e., the melanoma cells) from the non-sluprescent cells (i.e., the lung cells) so we can sequence their transcriptomes to identify the transciptional profiles associated with pulmonary melanoma metastasis.
Project description:In melanoma metastasis, the role of the AP-2alpha transcription factor, which is encoded by TFAP2A, is controversial as some findings have suggested tumor suppressor activity while other studies have shown high TFAP2A expression in node-positive melanoma associated with poor prognosis. Here we demonstrate that AP-2alpha facilitates melanoma metastasis through transcriptional activation of genes within the E2F pathway including EZH2. A BioID screen found that AP-2alpha interacts with members of the nucleosome remodeling and deacetylase (NuRD) complex. Loss of AP-2alpha removed activating chromatin marks in the promoters of EZH2 and other E2F target genes through activation of the NuRD repression complex. In melanoma cells, treatment witj tazemetostat, an FDA-approved and highly specific EZH2 inhibitor, substantially reduced anchorage-independent colony formation and demonstrated heritable anti-metastatic effects, which were dependent on AP-2alpha. Single cell RNA-seq analysis of a metastatic melanoma mouse model revealed hyperexpansion of Tfap2aHigh/E2F activated cell populations in transformed melanoma relative to progenitor melanocyte stem cells. These findings demonstrate that melanoma metastasis is driven by the AP-2alpha/EZH2 pathway and suggest that AP-2alpha expression can be used as a biomarker to predict responsiveness to EZH2 inhibitors for the treatment of advanced melanomas.
Project description:In melanoma metastasis, the role of the AP-2alpha transcription factor, which is encoded by TFAP2A, is controversial as some findings have suggested tumor suppressor activity while other studies have shown high TFAP2A expression in node-positive melanoma associated with poor prognosis. Here we demonstrate that AP-2alpha facilitates melanoma metastasis through transcriptional activation of genes within the E2F pathway including EZH2. A BioID screen found that AP-2alpha interacts with members of the nucleosome remodeling and deacetylase (NuRD) complex. Loss of AP-2alpha removed activating chromatin marks in the promoters of EZH2 and other E2F target genes through activation of the NuRD repression complex. In melanoma cells, treatment witj tazemetostat, an FDA-approved and highly specific EZH2 inhibitor, substantially reduced anchorage-independent colony formation and demonstrated heritable anti-metastatic effects, which were dependent on AP-2alpha. Single cell RNA-seq analysis of a metastatic melanoma mouse model revealed hyperexpansion of Tfap2aHigh/E2F activated cell populations in transformed melanoma relative to progenitor melanocyte stem cells. These findings demonstrate that melanoma metastasis is driven by the AP-2alpha/EZH2 pathway and suggest that AP-2alpha expression can be used as a biomarker to predict responsiveness to EZH2 inhibitors for the treatment of advanced melanomas.
Project description:Metastasis is the deadliest phase of cancer progression. Experimental models using immunodeficient mice have been used to gain insights into the mechanisms of metastasis. We report here the identification of a “metastasis aggressiveness gene expression signature” derived using human melanoma cells selected based on their metastatic potentials in a xenotransplant metastasis model. Comparison with expression data from human melanoma patients shows that this metastasis gene signature correlates with the aggressiveness of melanoma metastases in human patients. Many genes encoding secreted and membrane proteins are included in the signature, suggesting the importance of tumor-microenvironment interactions during metastasis. Keywords: disease state