Project description:To determine the different gene signatures between B lymphocytes from tumor draining lymph node (DLN) and normal lymph node (NLN), we have employed gene microarray as a discovery platform to identify gene signatures of tumor-educated B cells in DLN from tumor-bearing mice, taking NLN from normal mice as a control. We subcutaneously inoculated Balb/c mice with breast cancer cell line 4T1. Two weeks later, DLN was harvest and B cells were purified as descript in “treatment protocol”. From gene microarray, we found that B cells in DLN showed quite different transcript profiles from that in NLN.
Project description:To determine the influence of primary tumors on pre-metastatic lymph nodes, we have employed whole genome microarray expression profiling as a discovery platform to identify gene signatures of B cells from tumor-draining lymph nodes, compared with normal lymph nodes. We subcutaneously inoculated C57BL/6 mice with the 4T1 mammary carcinoma. Two weeks later, tumor-draining lymph nodes were dissociated and B cells (CD19+) were sorted. Lymph nodes B cells from normal mice without tumor bearing were set as controls.
Project description:To determine the influence of primary tumors on pre-metastatic lymph nodes, we have employed whole genome microarray expression profiling as a discovery platform to identify gene signatures of stromal cells from tumor-draining lymph nodes, compared with normal lymph nodes. We subcutaneously inoculated C57BL/6 mice with the 4T1 mammary carcinoma. Two weeks later, tumor-draining lymph nodes were dissociated and stromal cells (CD45-) were sorted. Lymph nodes stromal cells from normal mice without tumor bearing were set as controls.
Project description:Evolution of melanoma from a primary tumor to widespread metastasis is crucially dependent on lymphatic spread. The mechanisms regulating the initial step in metastatic dissemination via regional lymph nodes remain largely unknown. We have previously described a dysfunctional immune profile that precedes evidence of metastasis in the first node draining from the primary tumor, the sentinel lymph node (SLN). Herein, we explore the role of melanoma-derived extracellular vesicles (EVs) as mediators of this pre-metastatic niche through cargo-specific polarization of dendritic cells (DCs). Utilizing mass cytometry, pre-metastatic SLNs demonstrate compromised co-stimulatory CD80 expression compared to healthy lymph nodes. Similarly, DCs matured in vitro in the presence of melanoma EVs showed impaired co-stimulation and polarization towards a chronic inflammatory cytokine milieu. Profiling of melanoma EV cargo identified shared proteomic and RNA signatures including the signaling axis S100A8, S100A9 and cognate receptor TLR4. Mechanistically, S100A8 and S100A9 compromised DC maturation, a phenotype which was partially recovered following TLR4 blockade. Early evidence demonstrates similar EVs can be isolated from human afferent lymphatic fluid ex vivo. Taken together, we propose synergistic interactions among melanoma EV cargo are responsible for suppressing DC maturation, potentially explaining the survival of malignant melanocytes metastasizing into seemingly “normal” regional lymph nodes.
Project description:Analysis of purified immune and breast tumor cells from three major compartments where cancer and immune cells interact: primary tumor, tumor draining lymph nodes (tumor invaded or tumor free), and peripheral blood. The results suggests that node-positive patients’ immune regulation and functionality is down-regulated compared to node-negative patients. CD45+ Immune and ESA+ tumor cells were purified from breast cancer patients' primary tumor, tumor-draining lymph node, and peripheral blood (ficoll) and placed onto Agilent microarrays using the dye-swap method. A universal human reference was used as a reference for the patient samples.
Project description:Metastasis to lymph nodes is an early and prognostically important event in the progression of many human cancers, and is associated with expression of vascular endothelial growth factor-D (VEGF-D). Changes to lymph node vasculature occur during metastasis, and may establish a metastatic niche capable of attracting and supporting tumor cells. We used microarrays to characterise the molecular profiles of endothelial cells from lymph nodes draining metastatic (VEGF-D-overexpressing) and non-metastatic tumors, and to identify differentially-expressed genes that might have therapeutic or prognostic potential. Draining lymph nodes of metastatic (VEGF-D-overexpressing) or non-metastatic tumors were pooled from 1-5 mice and enzymatically digested. Lymph nodes draining metastatic tumors were included for the analysis only if macroscopically enlarged, indicating the presence of metastatic cells. After digestion, tumor cells and leukocytes were depleted via immunomagnetic selection, and the resulting lymph node stromal cells were cultured briefly. Podoplanin was then used as a positive immunomagnetic selection marker to enrich for lymphatic and other endothelial cells in the lymph node. RNA was isolated from biological duplicate lymph node endothelial cell (LN EC) preparations and analysed by microarray.
Project description:Gene expression profiling of whole tumor tissues consists of a heterogeneous population of tumor and stromal cells. We performed gene expression profiling of flow cytometry purified tumor cells from primary breast tumor tissues and metastatic lymph nodes in order to segregate tumor signatures from stromal signatures. The goal of this set of expression profiles was to understand the underlying mechanism of lymph node metastatic processes by comparing primary breast tumor cell gene expression profiles with that of lymph node metastatic tumor cells. Keywords: breast cancer, lymph node metastasis
Project description:We used scSEQ analysis to assess differences in the local tumor draining lymph node microenviroment, both on endothelial cells and immune cells
