Project description:Solid tumors exhibit significant phenotypic heterogeneity. This phenotypic heterogeneity yields the formation of phenotypically distinct subpopulations of cells within a single tumor. Within the 4T1 murine mammary adenocarcinoma cell line, we observe cells that invade either in collective chains or as single cells. Through this study, we sought to dissect the epigenetic differences between these invasively-distinct subpopulations.
Project description:Breast tumors often exhibit intratumoral heterogeneity. We hypothesized that phenotypically distinct clonal subpopulations in heterogeneous tumors may affect overall tumor morphology and cancer cell invasion. In order to study heterogeneous tumors, we isolated individual cells from a parental 4T1 murine mammary carcinoma cell line and generated four clonal subpopulations (E1, E2, A, and M). To characterize these subpopulations, we examined gene expression by performing bulk RNA-sequencing.
Project description:The methylation profiles of 6 cell lines derived from single clones of the 4T1 cell lines were assessed based on genomewide methylation levels The the promoters of genes that were overexpressed in intravasating clones were found had lower methylation levels for those clones relative to the others.
Project description:Genome-wide patterns of DNA methylation were quantified using the Illumina Infinium HumanMethylationEPIC BeadChip in DNA samples extracted from subpopulations of B cells.
Project description:We used 4T1 murine breast cancer cells to establish a syngeneic tumor model and found that liver metastatic cells exhibited serveral biological and molecular characteristic that are distinct from parental 4T1 cells. We used microarrays to analyze 4T1-3R_L cells exhibited several CSC related genes compared to 4T1 cells.
Project description:Novel therapies targeting cancer stem cells (CSCs), which play critical roles in chemo- and radio-resistance, metastasis, and possibly resistance against cancer immunotherapy including granulocyte-macrophage colony-stimulating factor (GM-CSF) gene-transduced tumor cell vaccines, may provide beneficial clinical outcomes. Here, we used syngeneic immunocompetent mice that allowed precise evaluation of the immunogenicity of the side population (SP) isolated from 4T1 murine breast carcinoma (4T1-SP) cells as putative CSCs. 4T1-SP cells showed various stem cell properties including high capacities for colony formation and tumorigenicity as well as high expression of phosphorylated signal transducer and activator of transcription-3 and vascular endothelial growth factor that are inductive of immune tolerance. Despite these progressive malignant characteristics of 4T1-SP cells, subcutaneous injection of non-transmissible Sendai virus-mediated GM-CSF gene-transduced 4T1-SP (4T1-SP/GM) cells remarkably impaired their tumorigenicity compared with that of the controls. This impairment of tumorigenicity was partially dependent on CD8+ T cells in concert with CD4+ T cells and natural killer cells. Notably, therapeutic vaccinations using irradiated 4T1-SP/GM cells markedly suppressed tumor development of subcutaneously transplanted 4T1-SP cells compared with that of the controls including irradiated 4T1-non-SP/GM cells. Tumor suppression was accompanied by robust accumulation of mature dendritic cells at vaccination sites and systemic Th1-based cellular immunity. Moreover, vaccinations comprising primary 4T1-SP cells isolated from transplanted 4T1-SP tumors elicited antitumor effects. cDNA microarray analysis showed that 4T1-SP cells predominantly expressed genes of cancer-related antigens including cancer/testis antigens. Collectively, we demonstrate that SP cell-based vaccinations induce effective antitumor immunity that may improve the efficacy of SP cell-based immunotherapy. Gene expression profiles were compared between sorted 4T1-SP and 4T1-NSP cells.
Project description:To delineate epithelial subpopulations in mouse mammary tissue, hematopoietic and endothelial cells were depleted from freshly isolated cell suspensions derived from mammary glands using fluorescence-activated cell sorting. The resultant Lin- population was fractionated into four distinct subpopulations using antibodies against CD29, CD24 and CD61. Based on the immunohistochemical phenotype, and in vivo and in vitro functional assays, these subpopulations were identified as fibroblast-containing stromal (CD29loCD24-), mammary stem cell (MaSC)-enriched (CD29hiCD24+CD61+), luminal progenitor (CD29loCD24+CD61+), and mature luminal (CD29loCD24+CD61-) cell subpopulations. Microarray profiling was used to derive gene expression signatures of these 4 subpopulations. The four mammary cell subpopulations were found to have distinct gene expression profiles. Four mammary cell subpopulations from 3-5 pooled mouse tissues were analysed. MS is for the MaSC-enriched cell subpopulation. LP is for the Luminal Progenitor subpopulation. ML is for the Mature Luminal subpopulation.
Project description:To delineate epithelial subpopulations in mouse mammary tissue, hematopoietic and endothelial cells were depleted from freshly isolated cell suspensions derived from mammary glands using fluorescence-activated cell sorting. The resultant Lin- population was fractionated into four distinct subpopulations using antibodies against CD29, CD24 and CD61. Based on the immunohistochemical phenotype, and in vivo and in vitro functional assays, these subpopulations were identified as fibroblast-containing stromal (CD29loCD24-), mammary stem cell (MaSC)-enriched (CD29hiCD24+CD61+), luminal progenitor (CD29loCD24+CD61+), and mature luminal (CD29loCD24+CD61-) cell subpopulations. Microarray profiling was used to derive gene expression signatures of these 4 subpopulations. The four mammary cell subpopulations were found to have distinct gene expression profiles.