Project description:In an inducible model of human breast cellular transformation, we map genome-wide chromatin binding of S100A8, S100A9 and Pol II. We show that the calcium-dependent cytokines S100A8 and S100A9 are recruited to numerous promoters and enhancers. This recruitment is associated with multiple DNA sequence motifs recognized by DNA-binding transcription factors that are linked to transcriptional activation and are important for transformation. Nuclear-specific expression of S100A8/A9 promotes oncogenic transcription and leads to enhanced breast transformation phenotype. These results suggest that, in addition to its classical cytokine function, S100A8/A9 can act as a transcriptional co-activator.
Project description:Studies using bone marrow chimeric mice revealed that S100A8/A9 expression on myeloid cells is essential for development of colon tumors. Our results thus reveal a novel role for myeloid-derived S100A8/A9 in activating specific downstream genes associated with tumorigenesis and in promoting tumor growth and metastasis. Subconfluent cultures of MC38 cells were serum-starved for 16 hrs and activated with 10ug/mL S100A8/A9 for 6 hrs. Total RNA was extracted from unactivated or activated cells. 2 replicates each per stimulated cells, unstimulated cells, and control cells.
Project description:Tumor-associated macrophages enhance the malignant phenotypes of esophageal squamous cell carcinoma (ESCC) cells. We have previously identified several factors associated with ESCC progression using an indirect co-culture assay between ESCC cells and macrophages. Here, we newly established a direct co-culture assay between ESCC cells and macrophages which is closer to the actual cancer microenvironment than an indirect co-culture assay. To investigate the gene expression changes by co-culture with macrophages, we performed cDNA microarray analysis between mono-cultured and co-cultured ESCC cells with macrophages. We found that the expression of S100 calcium binding protein A8 and A9 (S100A8 and S100A9) was enhanced in co-cultured ESCC cells with macrophages. S100A8 and S100A9 commonly exist stable and function as a heterodimer (S100A8/A9). S100A8/A9 is widely known as an inflammation marker. It also contributes to the enhancement of malignant phenotypes in several cancers. S100A8/A9 enhances the migration and invasion of ESCC cells by activating Akt and p38 MAPK signaling pathways. The higher expression levels of S100A8/A9 were associated with poor prognosis in ESCC patients. These results suggest that S100A8/A9 contributes to the progression of ESCC.
Project description:Studies using bone marrow chimeric mice revealed that S100A8/A9 expression on myeloid cells is essential for development of colon tumors. Our results thus reveal a novel role for myeloid-derived S100A8/A9 in activating specific downstream genes associated with tumorigenesis and in promoting tumor growth and metastasis.
Project description:S100A8 and S100A9 (aliases MRP8 and MRP14) are highly expressed in neutrophils and monocytes and are classified as damage-associated molecular pattern (DAMP) molecules or alarm molecules. However, the role of S100A8/A9 in aortic dissection has not been reported. In the present study, by employing an unbiased proteomics approach and RNA sequencing analysis , we found that the protein expression of calcium binding proteins S100A8/A9 were upregulated in the aorta and serum of TAAAD patients and also in a mouse model.
Project description:S100A8/A9 is a proinflammatory mediator released by myeloid cells during many acute and chronic inflammatory disorders. However, the precise mechanism of its release from the cytosolic compartment of neutrophils is still elusive. We report here that E-selectin-induced rapid S100A8/A9 release during inflammation occurs in a NLRP3 inflammasome-dependent fashion. Mechanistically, E-selectin engagement triggers Bruton?s tyrosine kinase dependent tyrosine phosphorylation of NLRP3. Concomitant potassium efflux via the voltage-gated potassium channel KV1.3 mediates ASC oligomerization. This is followed by caspase-1 cleavage and downstream activation of pore forming gasdermin D, enabling cytosolic S100A8/A9 to be released. Strikingly, E-selectin-mediated gasdermin D pore formation does not result in cell death, but is a transient process involving activation of the ESCRT-III membrane repair machinery. These findings do not only elucidate the molecular mechanisms of controlled S100A8/A9 release but also identify the NLRP3/gasdermin D axis as a rapid and reversible activation system in neutrophils during inflammation.
Project description:Frailty affects the physical, cognitive, and social domains exposing older adults to an increased risk of cardiovascular disease (CVD) and death. The mechanisms linking frailty and cardiovascular outcomes are mostly unknown. Here, we studied the association of abundance (flow cytometry) and gene expression profile (RNAseq) of stem/progenitor cells (HSPCs) and molecular markers of inflammaging (ELISA) with the cardiorespiratory phenotype and prospective adverse events of individuals classified according to levels of frailty. Two cohorts of older adults were enrolled in the study. In a cohort of pre-frail 35 individuals (average age: 75 years), a physical frailty score above the median identified subjects with initial alterations in cardiorespiratory function. RNA sequencing revealed S100A8/A9 upregulation in HSPCs from the bone marrow (>10-fold) and peripheral blood (>200-fold) of individuals with greater physical frailty. Moreover higher frailty was associated with increased alarmins S100A8/A9 and inflammatory cytokines in peripheral blood. We then studied a cohort of 104 more frail individuals (average age: 81 years) with multi-domain health deficits. Reduced levels of circulating HSPCs and increased S100A8/A9 concentrations were independently associated with the frailty index. Remarkably, low HSPCs and high S100A8/A9 simultaneously predicted major adverse cardiovascular events at 1-year follow-up after adjustment for age and frailty index. In conclusion, inflammaging characterized by alarmin and pro-inflammatory cytokines in pre-frail individuals is mirrored by the pauperization of HSPCs in frail older people with comorbidities. S100A8/A9 is upregulated within HSPCs, identifying a phenotype that associates with poor cardiovascular outcomes.
Project description:It has been reported that mesenchymal stem cells (MSC) derived from adult tissues are effective in promoting wound healing. However, the cell quality varies and cell number is limited as both depend on donations. Moreover, dissociated MSC delivered to an inflammatory lesion are subject to challenges to their survival and functions. Here we demonstrate that dropping of spheres of MSC derived from human embryonic stem cells (EMSC) onto murine dermal wound had much higher survival and efficacy than topical application of dissociated EMSC. RNA sequencing on cells isolated from the wound highlights the CXCL12-CXCR4 signalling in the EMSC sphere-mediated efficacy, which was verified via CXCL12 knockdown in EMSC and CXCR4 inhibition in target cells such as vascular endothelial cells, epithelial keratinocytes, and macrophage. Finally, we enhanced the biosafety of EMSC spheres by engineering the cells with an inducible suicide gene. Together, we propose topical application of EMSC spheres as an unlimited, quality-assured, safety-enhanced, and noninvasive therapy for wound healing and the CXCL12-CXCR4 axis as a key player in the treatment.
Project description:Schneider RK, Schenone M, Kramann R, Ferreira MV, Joyce CE, Hartigan C, Beier F, Brümmendorf TH, Gehrming U, Platzbecker U, Buesche G, Chen MC, Waters CS, Chen E, Chu LP, Novina CD, Lindsley RC, Carr SA, Ebert BL. Nat Med, 2016.
Heterozygous deletion of RPS14 occurs in del(5q) MDS and has been linked to impaired erythropoiesis, characteristic of this disease subtype. We generated a murine model with conditional inactivation of Rps14 and demonstrated a p53-dependent erythroid differentiation defect with apoptosis at the transition from polychromatic to orthochromatic erythroblasts resulting in age-dependent progressive anemia, megakaryocyte dysplasia, and loss of hematopoietic stem cell (HSC) quiescence. Using quantitative proteomics, we identified significantly increased expression of proteins involved in innate immune signaling, particularly the heterodimeric S100A8/S100A9 proteins in purified erythroblasts. S100A8 expression was significantly increased in erythroblasts, monocytes and macrophages and recombinant S100A8 was sufficient to induce an erythroid differentiation defect in wild-type cells. We rescued the erythroid differentiation defect in Rps14 haploinsufficient HSCs by genetic inactivation of S100a8 expression. Our data link Rps14 haploinsufficiency to activation of the innate immune system via induction of S100A8/A9 and the p53-dependant erythroid differentiation defect in del(5q) MDS.
Project description:Mesenchymal stem cells (MSCs) are recruited from the blood stream to tumors, healing wounds or sites of tissue injury by multiple growth factors and chemokines where they differentiate into e.g. fibroblasts or endothelial cells. Engrafted at the sites of tissue damage, they secrete growth factors and cytokines that facilitate healing. Inhibition of MSC proliferation by prolonged application of local anesthetics (commonly used after surgery) could delay wound closure and promote wound dehiscence.