Project description:Tissue clearing technique may be one of the most powerful strategies for a comprehensive and unbiased analysis of disease progression. Here, we improved a tissue clearing protocol and explored its application in a mouse tumour model of experimental lung metastasis. We established an integrated pipeline for 3D profiling of the tumour microenvironment in combination with our new clearing protocol and machine learning. This pipeline distinguished each cellular component within the tumour microenvironment, and provided information on their spatial relationships. We further explored the role of TGF-b in the tumour microenvironment using this integrated pipeline. TGF-b-stimulated cancer cells enhanced metastatic colonization of unstimulated-cancer cells in vivo when both cells were mixed. RNA-sequencing analysis showed that expression of the genes related to coagulation and inflammation were up-regulated in TGF-b-stimulated cancer cells. Further, 3D profiling of the tumour microenvironments revealed accumulation of platelets or macrophages with TGF-b-stimulated cancer cells, suggesting that TGF-b might promote remodelling of the tumour microenvironment through the activation of these cellular components at the metastatic sites, which further enhances the colonization of cancer cells. Hence, an integrated pipeline that combines tissue clearing, 3D imaging, and machine learning will help further the understanding of the role of the tumour microenvironment.
Project description:Tissue clearing is one of the most powerful strategies for a comprehensive analysis of disease progression. Here, we established an integrated pipeline that combines tissue clearing, 3D imaging, and machine learning and applied to a mouse tumour model of experimental lung metastasis using human lung adenocarcinoma A549 cells. This pipeline provided the spatial information of the tumour microenvironment. We further explored the role of transforming growth factor-β (TGF-β) in cancer metastasis. TGF-β-stimulated cancer cells enhanced metastatic colonization of unstimulated-cancer cells in vivo when both cells were mixed. RNA-sequencing analysis showed that expression of the genes related to coagulation and inflammation were up-regulated in TGF-β-stimulated cancer cells. Further, whole-organ analysis revealed accumulation of platelets or macrophages with TGF-β-stimulated cancer cells, suggesting that TGF-β might promote remodelling of the tumour microenvironment, enhancing the colonization of cancer cells. Hence, our integrated pipeline for 3D profiling will help the understanding of the tumour microenvironment.
Project description:Interactions between mutant cells and their environment play a key role in determining cancer susceptibility. However, our understanding of how the pre-cancerous microenvironment contributes to early tumorigenesis remains limited. Here, we show that newly emerging tumours at their most incipient stages shape their microenvironment in a critical process that determines their survival. Analysis of nascent squamous tumours in the upper gastrointestinal tract of the mouse reveals that the stress response of early tumour cells instructs the underlying mesenchyme to form a supportive “pre-cancerous niche”, which dictates the long-term outcome of epithelial lesions. Stimulated fibroblasts beneath emerging tumours activate a wound healing response that triggers a dramatic remodelling of the underlying extracellular matrix, resulting in the formation of a fibronectin-rich stromal scaffold that promotes tumour growth. Functional heterotypic 3D culture assays and in vivo grafting experiments, combining carcinogen-free healthy epithelium and tumour derived stroma, demonstrate that the pre-cancerous niche alone is sufficient to confer tumour properties to normal epithelial cells. We propose a model where both mutations and the stromal response to genetic stress together define the likelihood of early tumours to persist and progress towards more advanced disease stages.
Project description:Extracellular pH (pHe) is lower in many tumors than in the corresponding normal tissue. Acidic tumor microenvironment has been shown to facilitate epithelial mesenchymal transition (EMT) and tumor metastasis, while the mechanisms underlying tumor acidic microenvironment-induced tumor cell metastasis remain undefined. Here, we aimed to investigate the tumor metastasis and the EMT by acidic microenvironment and to explore their mechanisms and clinical significance in lung cancer. Results showed that acidic pHe remarkably enhanced invasion ability of lung cells accompanying with increased mesenchymal and decreased epithelial markers. Moreover, acidic pHe triggered the inhibition of microRNA-7 (miR-7) expression and activation of TGF-β2/SMAD signaling. Mechanistic studies showed that TGF-β2 is a direct potential target gene of miR-7, and acidity-induced metastasis could be abolished by treatment with a TGFβRI inhibitor, anti-TGF-β2 antibody and miR-7 mimic, respectively. The clinical samples further revealed that miR-7 was decreased in lung tissues and antagonistically correlated with TGF-β2 expression, associating with overall survival and metastasis. In conclusion, our study indicated that acidic pHe showed enhanced invasive potential, and enhanced potential to develop experimental metastases by a novel mechanism involving tumor acidic microenvironment-induced regulation of miR-7/TGF-β2/SMAD axis. Our findings suggest that the possibility that pHe of the primary tumor may be an important prognostic parameter for lung cancer patients merit clinical investigation. Moreover, miR-7 may serve as prognostic molecular marker and a novel therapeutic target for lung cancer.
Project description:Cancer associated fibroblasts characterized by an myofibroblastic phenotype play a major role in the tumour microenvironment, being associated with poor prognosis. We found that this cell population is made in part by senescent fibroblasts in vivo. As senescent fibroblasts and myofibroblasts have been shown to share similar tumour promoting functions in vitro we compared the transcriptosomes of these two fibroblast types and performed RNA-seq of human foetal foreskin fibroblasts 2 (HFFF2) treated with 2ng/ml TGF-beta-1 to induce myofibroblast differentiation or 10Gy gamma irradiation to induce senescence. We isolated RNA 7 days upon this treatments changing the medium 3 days before the RNA extraction. A series of SAM alignment files (named after the sample names, for simplicity) are available under http://www.ebi.ac.uk/arrayexpress/experiments/E-MTAB-3101/files/ .
Project description:The seed-and-soil hypothesis was described over a century ago to describe why cancer cells (seeds) grow in certain organs (soil). Since then, the genetic properties that define the cancer cells have been heavily investigated, however, the genetic mediators within the organ microenvironment that mediate successful metastatic growth are less understood. In these studies, a set of human breast cancer patient-derived xenograft (PDX) metastasis models were utilized. Mammary tumors and metastases to the liver, lung, and brain were RNA-sequenced with the goal of identifying complementary cancer and organ-specific genetic properties that mediate metastatic growth. During metastatic growth of PDXs, the genetic changes that occurred in the liver and lung microenvironment were more consistent and higher in magnitude than the cancer cell transcriptomes . Integration of the liver microenvironment gene signature into genetic data from liver metastasis autopsy samples or fine-needle aspirates revealed the contribution of the microenvironment to the metastatic transcriptome. These insights identify cancer and organ-specific genetic drivers of metastasis.
Project description:Mesothelioma is a cancer derived from mesothelial cells, most commonly arising from the pleura or the peritoneum. Immune checkpoint therapy (ICT) has shown survival benefit for pleural mesothelioma, but little is known about the response in peritoneal mesothelioma. Most preclinical mesothelioma models involve subcutaneous cancer cell implantation, which lacks the relevant tumour microenvironment of peritoneal mesothelioma and does not resemble the clinical presentation. We therefore set out to explore the influence of location on the mesothelioma tumour microenvironment, comparing pleural, peritoneal, and subcutaneous models using identical cell line-derived syngeneic mesotheliomas. We found that the peritoneal location conferred an anti-inflammatory tumour microenvironment, characterised by low IFN, TNFα, and STAT signalling activity, low immune cell infiltration and a gene signature associated with non-response to ICT. ICT was effective in subcutaneous models, but the same cell line-derived tumours were irresponsive when inoculated intraperitoneally. Together, these findings show that peritoneal location is associated with an immune suppressive tumour microenvironment.
Project description:We performed spatial transcriptome profiling (ST-seq) on nine fresh frozen tissue sections to understand the immunophenotypes; immune cell types, states and their spatial location within the clear cell renal cell carcinoma (ccRCC) tumour microenvironment (TME).