Project description:This study shows that Col6a1cre+ cells constitute a subpopulation of cancer-associated fibroblasts in colitis-associated cancer that partly maintains its homeostatic features, while its activation is characterized by the acquisition of a distinct proangiogenic signature, which could be associated with their initial perivascular location.
Project description:Cancer-associated fibroblasts (CAFs) comprise a group of heterogeneous subpopulations with distinct identities indicative of their diverse origins, activation patterns, and pro-tumorigenic functions. CAFs originate mainly from resident fibroblasts, which are activated upon different stimuli, including growth factors and inflammatory mediators, but the extent to which they also maintain some of their homeostatic properties, at least at the earlier stages of carcinogenesis, is not clear. In response to cytokines, such as interleukin 1 (IL-1) and tumor necrosis factor (TNF), as well as microbial products, CAFs acquire an immunoregulatory phenotype, but its specificity and pathophysiological significance in individual CAF subsets is yet to be determined. In this study, we analyzed the properties of Col6a1-positive fibroblasts in colitis-associated cancer. We found that Col6a1+ cells partly maintain their homeostatic features during adenoma development, while their activation is characterized by the acquisition of a distinct proangiogenic signature associated with their initial perivascular location. In vitro and in vivo experiments showed that Col6a1+ cells respond to innate immune stimuli and exert pro-tumorigenic functions. However, Col6a1+-specific inhibition of TNF receptor 1 (TNFR1) or IL-1 receptor (IL-1R) signaling does not significantly affect tumorigenesis, suggesting that activation of other subsets acts in a compensatory way or that multiple immune stimuli are necessary to drive the proinflammatory activation of this subset. In conclusion, our results show that adenoma-associated CAF subsets can partly maintain the properties of homeostatic fibroblasts while they become activated to support tumor growth through distinct and compensatory mechanisms.
Project description:Collagen 6 (COL6) is known for its role in a spectrum of congenital muscular dystrophies, which are often accompanied by respiratory dysfunction. However, little is known regarding the function of COL6 in the lung. We confirmed the presence of COL6 throughout the basement membrane region of mouse lung tissue. We studied lung structure and organization in a previously described Col6a1-/- mouse, which do not produce detectable COL6 in the lung. The Col6a1-/- mouse displayed multiple histopathological alveolar and airway abnormalities. The airspaces of Col6a1-/- lungs appeared simplified, with larger (29%, p<0.01) and fewer (31%, p<0.001) alveoli. These airspace abnormalities included a reduction in IsolectinB4+ alveolar capillaries and Sftpc+ ATII cells. Alterations in lung function consistent with these histopathological changes were evident. Col6a1-/- mice also displayed multiple airway changes including increased branching (59%, p<0.001), increased mucosal thickness (34%, p<0.001) and increased epithelial cell density (13%, p<0.001). Comprehensive transcriptome analysis revealed loss of COL6 is associated with reductions in integrin-paxillin-PI3K signaling in vivo. In vitro, COL6 promoted steady-state phospho-paxillin levels and reduced cell density (16-28%, p<0.05) at confluence. Inhibition of PI3K, or its downstream effectors, resulted in increased cell density to a level similar to that seen on matrices lacking COL6.
Project description:Synovial fibroblasts critically contribute to the pathogenesis of rheumatoid arthritis (RA) by acquiring either a pro-inflammatory or tissue-destructive phenotype. To explore the molecular mechanisms underlying the tissue-destructive fibroblast phenotype in arthritis, we performed bulk RNA-sequencing analysis on the synovial fibroblasts which were isolated from Col6a1-Cre-Ets1-flox/flox (Ets1ΔFib) and Ets1-flox/flox (Ets1flox) mice.
Project description:Although ageing is usually regarded as a high risk of cancer, the relationship between ageing stromal microenvironment and spontaneous cancer initiation is poorly understood. In murine models of DSS-induced colitis and AOM/DSS-induced colitis-associated cancer (CAC), we found ageing significantly inhibit both intestinal wound healing and simultaneous CAC initiation. In young mice, through conditional lineage tracing, a novel and important source of fibroblasts transformed from intestinal smooth muscle cells (ISMCs) was identified during intestinal wound healing, which existed persistently in CAC. We further found that activation of YAP/TAZ in ISMCs is required for their transformation into fibroblasts. However, in ageing intestinal microenvironment, the failure of YAP/TAZ activation in ISMCs led to reduced fibroblast numbers, orchestrating the inhibition of wound healing and simultaneous inhibition of CAC initiation. Collectively, our work revealed an important role of ageing stromal microenvironment in intestinal wound healing and CAC development. Meanwhile, our work also discovered an important source of fibroblasts involved in colitis and CAC.
Project description:Objective: Ulcerative colitis (UC) is a chronic disease with rising incidence and unclear etiology. The application of mass spectrometry-based post-genomic analysis methods shall support the development of molecular biomarker signatures providing status information with regard to UC pathomechanisms. Design: Pathomechanisms characteristic for UC were assessed by proteome profiling of human tissue specimen, obtained from five distinct colon locations each of 12 patients. Systemic disease-associated alterations were investigated by mass spectrometry-based multi-omics analyses comprising proteins, metabolites and eicosanoids of plasma obtained from UC patients during disease and upon remission in comparison to healthy controls. Results: Proteome profiling results identified colitis-associated activation of neutrophils, macrophages, B- and T-cells, platelets, fibroblasts and endothelial cells and indicated hypoxic stress, as well as a general reduction of mitochondrial proteins accompanying the establishment of apparent healing-promoting activities as well as scar formation. While the immune cells mainly contributed pro-inflammatory proteins, the colitis-associated epithelial cells, fibroblasts, endothelial cells and platelets predominantly formed anti-inflammatory and healing-promoting proteins. Blood plasma proteomics indicated chronic inflammation and platelet activation, whereas plasma metabolomics identified disease-associated deregulation of bile acids, eicosanoids and gut microbiome-derived metabolites. Upon remission, several, but not all, molecular candidate biomarker levels recovered to normal levels. These findings may indicate that pathomechanisms related to gut functions, gut microbiome status, microvascular damage and metabolic dysregulation associated with hypoxia may do not resolve uniformly upon remission. Conclusions: The establishment of disease-associated biomarker profiles related to molecular UC pathomechanisms may support the establishment of bioassays with improved prognostic power aiding individualized therapy.
Project description:Non-small cell lung cancer (NSCLC) is a major cause of cancer-associated mortality worldwide, and bone metastasis is the most prevalent event observed in patients with advanced NSCLC. However, the pathogenesis of bone metastases has not been fully elucidated. In the present study, differentially expressed genes (DEGs) were identified by gene expression microarray analysis of NSCLC tissue samples with or without bone metastases. Subsequently, collagen family collagen 6A1 (COL6A1) was chosen as the target gene through Ingenuity Pathway Analysis and reverse transcription-quantitative (RT-q)PCR validation of the top eight DEGs. COL6A1 was overexpressed or knocked down, and the proliferation and invasion of NSCLC cells was assessed using Cell Counting Kit-8, colony formation and Transwell invasion assays. Additionally, the osteogenic capacity of HOB and hES-MP 002.5 cells was assessed using RT-qPCR, western blotting, Alizarin Red staining and alkaline phosphatase staining. A total of 364 DEGs were identified in NSCLC tissues with bone metastases compared with NSCLC tissues without bone metastases, including 140 upregulated genes and 224 downregulated genes. Gene Ontology analysis indicated that the upregulated and downregulated genes were primarily enriched in ‘cellular process’, ‘metabolic process’ and ‘biological regulation’. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis revealed that the upregulated genes were primarily enriched in ‘cysteine and methionine metabolism’, ‘oxidative phosphorylation’ and the ‘ribosome’, while the downregulated genes were primarily enriched in ‘transcriptional mis-regulation in cancer’, ‘ribosome’ and ‘mitophagy in animals’. COL6A1 was highly expressed in NSCLC tissue samples with bone metastases. Functionally, COL6A1 overexpression induced the proliferation and invasion of HARA cells, and knockdown prevented the proliferation and invasion of HARA-B4 cells. Finally, it was demonstrated that HOB and hES-MP 002.5 cells exhibited osteogenic capacity, and overexpression of COL6A1 in HARA cells increased adhesion of these cells to the osteoblasts, whereas knockdown of COL6A1 in HARA-B4 cells reduced their adhesive ability. In conclusion, COL6A1 may serve as a potential diagnostic marker and therapeutic target for bone metastasis in NSCLC.
Project description:The colon cancer associated fibroblasts are part of the tumor microenvironment and has been shown to facilitate colon cancer progression by secretion of various signaling molecules and growth hormones. Similarly, the fibroblasts associated with colitic colons secrete pro-inflammatory cytokines that promote inflammation of the colon. However, the molecular mechanisms that underlie these gene expression changes in these fibroblasts is unclear. To characterize the epigenetic mechanisms that may contribute to the gene expression changes in these fibroblasts, we performed RNA-seq and MBD-isolated genome sequencing (MiGS or MBD-seq) on colon associated fibroblasts isolated from normal, colitis and cancer patients.
Project description:Interleukin (IL)-11 is a member of the IL-6 family of cytokines and involved in multiple cellular responses, including tumor development. However, the origin and functions of IL-11-producing (IL-11+) cells are not fully understood. To characterize IL-11+ cells in vivo, we generated Il11 reporter mice. IL-11+ cells appeared in the colon of murine tumor and acute colitis models. Il11ra1 or Il11 deletion attenuated the development of colitis-associated colorectal cancer. IL-11+ cells expressed fibroblast markers, and genes associated with cell proliferation and tissue repair. IL-11 induced the activation of colonic fibroblasts and epithelial cells through phosphorylation of STAT3. Human cancer database analysis revealed that a set of genes enriched in IL-11+ fibroblasts was elevated in human colorectal cancer, and correlated with reduced recurrence-free survival. Together, IL-11+ fibroblasts activate both tumor cells and fibroblasts via secretion of IL-11, thereby constituting a feed forward loop between tumor cells and fibroblasts in the tumor microenvironment.