Project description:How disseminated tumor cells (DTCs) engage specific stromal components in distant organs for survival and outgrowth is a critical but poorly understood step of the metastatic cascade. Previous studies have demonstrated the importance of the epithelial-mesenchymal transition (EMT) in promoting the cancer stem cell properties needed for metastasis initiation, while the reverse process of mesenchymal-epithelial transition (MET) is required for metastatic outgrowth. Here we report that this paradoxical requirement for simultaneous induction of both MET and cancer stem cell traits in DTCs is provided by bone vascular niche E-selectin. Using cell surface alkoxyamine-biotinylation and label-free LC-MS/MS, Glg1 was identified as a top candidate Fut3/Fut6-dependent E-selectin ligand. We functionally validated their involvement in the formation of bone metastasis. These findings provide unique insights into the functional role of E-selectin as a component of the vascular niche criticalfor metastatic colonization in bone.
Project description:Loss of MLL3 facilitates mesenchymal cells to acquire a mesenchymal/epithelial hybrid state during metastatic colonization. The MET occurring in distant metastases is likely driven by stromal signals in the metastatic niche. One signaling pathway that promotes the MET is the activation of protein kinase A (PKA). The MET hybrid cells can be identified as CD44+CD104+/high. Forskolin treatment generated significantly more CD44+CD104high hybrid cells in MLL3-mutant cells than the WT MDA-MB-231 cells. While both WT and MLL3-mutant CD44+CD104high hybrid EMT cells showed significantly increased lung metastatic ability than the counterpart CD44+CD104low mesenchymal cells, the MLL3-mutant hybrid cells showed a much greater metastasis-initiating ability than the WT hybrid cells. Here we reported the gene expression profiles of CD44+CD104high E/M hybird and CD44+CD104-/low mesenchymal cell populations sorted from Foskolin-treated, WT MDA-MB-231 cells.
Project description:Loss of MLL3 facilitates mesenchymal cells to acquire a mesenchymal/epithelial hybrid state during metastatic colonization. The MET occurring in distant metastases is likely driven by stromal signals in the metastatic niche. One signaling pathway that promotes the MET is the activation of protein kinase A (PKA). The MET hybrid cells can be identified as CD44+CD104+/high. Forskolin treatment generated significantly more CD44+CD104high hybrid cells in MLL3-mutant cells than the WT MDA-MB-231 cells. While both WT and MLL3-mutant CD44+CD104high hybrid EMT cells showed significantly increased lung metastatic ability than the counterpart CD44+CD104low mesenchymal cells, the MLL3-mutant hybrid cells showed a much greater metastasis-initiating ability than the WT hybrid cells. Here we reported the gene expression profiles of CD44+CD104high E/M hybird and CD44+CD104-/low mesenchymal cell populations sorted from Foskolin-treated, MLL3-null MDA-MB-231 cells.
Project description:Incomplete understanding of metastatic disease mechanisms continues to hinder effective treatment of cancer. Despite remarkable advancements toward the identification of druggable targets, treatment options for patients in remission following primary tumor resection remain limited. Bioengineered human tissue models of metastatic sites capable of recreating the physiologically relevant milieu of metastatic colonization may strengthen our grasp of cancer progression and contribute to the development of effective therapeutic strategies. We report the use of an engineered tissue model of human bone marrow (eBM) to identify microenvironmental cues regulating cancer cell proliferation and to investigate how triple-negative breast cancer cell lines influence hematopoiesis. Notably, individual stromal components of the BM niche (osteoblasts, endothelial cells, and mesenchymal stem/stromal cells) were each critical for regulating tumor cell quiescence and proliferation in the three-dimensional eBM niche. In this data set, we provide transcriptomic information from bulk RNA sequencing of MDA-MB-231 cancer cells that were pre-conditioned by being co-cultured on variations of eBM tissues. We envision that this human tissue model will facilitate studies of niche-specific metastatic progression and individualized responses to treatment.
Project description:In cancer progression to metastasis, disseminated cancer cells frequently lodge near vasculature in secondary organs. However, our understanding of the cellular crosstalk evoked at perivascular sites is still rudimentary. In this study, we identified an inter-cellular machinery governing formation of a pro-metastatic vascular niche during breast cancer colonization in lungs. Transcriptomic analysis of endothelial cells (ECs) isolated from mouse lungs with metastases revealed a marked upregulation of genes linked to proliferation, inflammation and numerous secreted proteins. We showed that four secreted factors, INHBB, SCGB3A1, OPG and LAMA1, induced in ECs form a supportive niche that promotes metastasis in mice, by enhancing stem cell properties and survival ability of cancer cells. Interestingly, the blocking vascular endothelial cell growth factor (VEGF), a major cytokine regulating EC behaviors, dramatically suppressed EC proliferation whereas no impact was observed on the expression of the four vascular niche factors in lung ECs. We found that the formation of a vascular niche is correlated with inflammation, and revealed that metastasis-associated macrophages are essential for production of all of four niche factors in lung ECs. Macrophages are activated via TNC-TLR4 at perivasculature and sequentially stimulate ECs to produce the four niche factors. Thus, our findings provide mechanistic insights into the formation of a perivascular niche and offer the possibility that targeting macrophages may synergize with existing anti-angiogenic drugs to effectively suppress vascular function in metastatic colonization. We used microarrays to analyze the global changes of gene expression in lung endothelial cells at different stages of lung colonization by MDA-MB-231-LM2 cells
Project description:At birth, newborns are exposed to gut microbiota, which plays a critical role in host physiology. A reduced level of microbial diversity has been associated with necrotizing enterocolitis (NEC), one of the most deadly diseases in premature infants, but the underlying disease mechanisms are still poorly understood. Although the epithelial turnover of germ free mice is significantly delayed compared to conventionally raised mice, it remains unclear how gut microbiota exposure in the early postnatal period promotes stem cell renewal and differentiation. By analyzing genetic and experimental mouse models and performing single cell analysis, we demonstrate that gut microbiota promotes stem cell differentiation through the activation of critical stromal niche components. Our single cell analysis reveals that gut microbiota controls the size and heterogeneity of macrophage populations that secrete Wnt ligands, thereby maintaining the proliferation of intestinal telocytes, a recently identified gut mesenchymal stem cell niche. We show that stem cell differentiation, when impaired by antibiotic treatment promotes NEC, while treatment with Lactobacillus, which in NEC is dramatically less abundant, rescues NEC-like pathology through the activation of macrophage and telocyte niches. Our work highlights the mechanisms of how gut microbiota-facilitate mesenchymal niche proliferation which supports stem cell differentiation in early postnatal development.
Project description:Loss of MLL3 facilitates mesenchymal cells to acquire a mesenchymal/epithelial hybrid state during metastatic colonization. MLL3 loss led to IFNg signaling upregulation, which contributes to the induction of hybrid EMT cells and the enhanced metastatic capacity. Here we reported the gene expression profiles of WT and MLL3-KO MDA-MB-231 cells.
Project description:In cancer progression to metastasis, disseminated cancer cells frequently lodge near vasculature in secondary organs. However, our understanding of the cellular crosstalk evoked at perivascular sites is still rudimentary. In this study, we identified an inter-cellular machinery governing formation of a pro-metastatic vascular niche during breast cancer colonization in lungs. Transcriptomic analysis of endothelial cells (ECs) isolated from mouse lungs with metastases revealed a marked upregulation of genes linked to proliferation, inflammation and numerous secreted proteins. We showed that four secreted factors, INHBB, SCGB3A1, OPG and LAMA1, induced in ECs form a supportive niche that promotes metastasis in mice, by enhancing stem cell properties and survival ability of cancer cells. Interestingly, the blocking vascular endothelial cell growth factor (VEGF), a major cytokine regulating EC behaviors, dramatically suppressed EC proliferation whereas no impact was observed on the expression of the four vascular niche factors in lung ECs. We found that the formation of a vascular niche is correlated with inflammation, and revealed that metastasis-associated macrophages are essential for production of all of four niche factors in lung ECs. Macrophages are activated via TNC-TLR4 at perivasculature and sequentially stimulate ECs to produce the four niche factors. Thus, our findings provide mechanistic insights into the formation of a perivascular niche and offer the possibility that targeting macrophages may synergize with existing anti-angiogenic drugs to effectively suppress vascular function in metastatic colonization. We used microarrays to analyze the global changes of gene expression in metastasis-associated lung endothelial cells upon macrophage-depleted conditions
Project description:In cancer progression to metastasis, disseminated cancer cells frequently lodge near vasculature in secondary organs. However, our understanding of the cellular crosstalk evoked at perivascular sites is still rudimentary. In this study, we identified an inter-cellular machinery governing formation of a pro-metastatic vascular niche during breast cancer colonization in lungs. Transcriptomic analysis of endothelial cells (ECs) isolated from mouse lungs with metastases revealed a marked upregulation of genes linked to proliferation, inflammation and numerous secreted proteins. We showed that four secreted factors, INHBB, SCGB3A1, OPG and LAMA1, induced in ECs form a supportive niche that promotes metastasis in mice, by enhancing stem cell properties and survival ability of cancer cells. Interestingly, the blocking vascular endothelial cell growth factor (VEGF), a major cytokine regulating EC behaviors, dramatically suppressed EC proliferation whereas no impact was observed on the expression of the four vascular niche factors in lung ECs. We found that the formation of a vascular niche is correlated with inflammation, and revealed that metastasis-associated macrophages are essential for production of all of four niche factors in lung ECs. Macrophages are activated via TNC-TLR4 at perivasculature and sequentially stimulate ECs to produce the four niche factors. Thus, our findings provide mechanistic insights into the formation of a perivascular niche and offer the possibility that targeting macrophages may synergize with existing anti-angiogenic drugs to effectively suppress vascular function in metastatic colonization. We used microarrays to analyze the global changes of gene expression in metastasis-associated lung endothelial cells upon VEGFA neutralization