Project description:We examined the intratumor heterogeneity in S2-VP10 xenograft by single-cell RNA-sequencing. We found a hierarchical tumor progression originating from ROR1high cells with a partial EMT gene signature. We also found that ROR1high cells have the strong capacity as tumor-initiating cells to support tumorigenecity, chemoresistance, and metastasis. CUT&RUN and ATAC-sequencing revealed that ROR1 gene expression is regulated through YAP-BRD4 axis. Together, these data uncover a role for ROR1high cells in tumor progression, suggesting that ablating ROR1high tumor-initiating cells may be the alternative therapeutic strategy in pancreatic adenocarcinoma.
Project description:We examined the intratumor heterogeneity in S2-VP10 xenograft by single-cell RNA-sequencing. We found a hierarchical tumor progression originating from ROR1high cells with a partial EMT gene signature. We also found that ROR1high cells have the strong capacity as tumor-initiating cells to support tumorigenecity, chemoresistance, and metastasis. CUT&RUN and ATAC-sequencing revealed that ROR1 gene expression is regulated through YAP-BRD4 axis. Together, these data uncover a role for ROR1high cells in tumor progression, suggesting that ablating ROR1high tumor-initiating cells may be the alternative therapeutic strategy in pancreatic adenocarcinoma.
Project description:We examined the intratumor heterogeneity in S2-VP10 xenograft by single-cell RNA-sequencing. We found a hierarchical tumor progression originating from ROR1high cells with a partial EMT gene signature. We also found that ROR1high cells have the strong capacity as tumor-initiating cells to support tumorigenecity, chemoresistance, and metastasis. CUT&RUN and ATAC-sequencing revealed that ROR1 gene expression is regulated through YAP-BRD4 axis. Together, these data uncover a role for ROR1high cells in tumor progression, suggesting that ablating ROR1high tumor-initiating cells may be the alternative therapeutic strategy in pancreatic adenocarcinoma.
Project description:We examined the intratumor heterogeneity in S2-VP10 xenograft by single-cell RNA-sequencing. We found a hierarchical tumor progression originating from ROR1high cells with a partial EMT gene signature. We also found that ROR1high cells have the strong capacity as tumor-initiating cells to support tumorigenecity, chemoresistance, and metastasis. CUT&RUN and ATAC-sequencing revealed that ROR1 gene expression is regulated through YAP-BRD4 axis. Together, these data uncover a role for ROR1high cells in tumor progression, suggesting that ablating ROR1high tumor-initiating cells may be the alternative therapeutic strategy in pancreatic adenocarcinoma.
Project description:Intratumor heterogeneity is a major obstacle to effective cancer treatment. Current methods to study intratumor heterogeneity using single-cell RNA sequencing (scRNAseq) lack information on the spatial organization of cells. While state-of-the art spatial transcriptomics methods capture the spatial distribution, they either lack single cell resolution or have relatively low transcript counts. Here, we introduce spatially annotated single cell sequencing, based on the previously developed functional single cell sequencing (FUNseq) technique, to spatially profile tumor cells with deep scRNA-seq and single cell resolution. Using our approach, we profiled cells located at different distances from the center of a 2D epithelial cell mass. By profiling the cell patch in concentric bands of varying width, we showed that cells at the outermost edge of the patch responded strongest to their local microenvironment, behaved most invasively, and activated the process of epithelial-to-mesenchymal transition (EMT) to migrate to lowconfluence areas. We inferred cell-cell communication networks and demonstrated that cells in the outermost ~10 cell wide band, which we termed the invasive edge, induced similar phenotypic plasticity in neighboring regions. Applying FUNseq to spatially annotate and profile tumor cells enables deep characterization of tumor subpopulations, thereby unraveling the mechanistic basis for intratumor heterogeneity.
Project description:Intratumor heterogeneity and phenotypic plasticity drive tumour progression and therapy resistance. Oncogene dosage variation contributes to cell state transitions and phenotypic heterogeneity, thereby providing a substrate for somatic evolution. Nonetheless, the genetic mechanisms underlying phenotypic heterogeneity are still poorly understood. Here, we show that extrachromosomal DNA (ecDNA) is a major source of high-level focal amplification in key oncogenes and a major contributor of MYC heterogeneity in pancreatic ductal adenocarcinoma (PDAC). We demonstrate that ecDNAs drive varying levels of MYC dosage, depending on their regulatory landscape, enabling cancer cells to rapidly and reversibly adapt to microenvironmental changes. In absence of selective pressure, a high ecDNA copy number imposes a substantial fitness cost on PDAC cells. We also show that MYC dosage affects cell morphology and dependence of cancer cells on stromal niche factors. Our work provides the first detailed analysis of ecDNAs in PDAC and describes a new genetic mechanism driving MYC heterogeneity in PDAC.