ABSTRACT: We performed gene expression profiling to evaluate whether macrophages from pristane-treated WT and Sparc-/- mice display a different inflammatory phenotype
Project description:The aim of this study was evaluate the transcriptome changes in the comparison between triple negative tumors with increased SPARC expression and triple negative tumors with decreased SPARC expression according to Nagai et al., 2011 (Breast Cancer Res Treat (2011) 126:1–14) The results generated could be of particular interest to better define the prognostic impact of SPARC expression in triple negative breast tumors
Project description:SPARC is a member of matricellular protein, and emerging evidence suggests that it plays a critical role in integrated metabolic and inflammatory responses. However, the mechanism how SPARC activates inflammation is still unanswered. Here we showed that excess SPARC induced sterile inflammation, and converted anti-inflammatory macrophage to pro-inflammatory macrophage. RNA-sequencing analysis revealed that SPARC elicits interferon-stimulated genes (ISGs) by transcription factor IRF7. SPARC also dampened mitochondrial respiration that induced pro-glycolytic inflammatory macrophage. Altogether, we discovered a mechanism how SPARC triggers sterile inflammatory response in anti-inflammatory macrophage, and this implicates the potential role of SPARC as a modulator of anti-inflammatory macrophages to maintain tissue homeostasis.
Project description:SPARC is a matricellular glycoprotein involved in regulation of the extracellular matrix, growth factors, adhesion, and migration. SPARC-null mice have altered basement membranes and develop posterior sub-capsular cataracts with cell swelling and equatorial vacuoles. Exchange of fluid, nutrients, and waste products in the avascular lens is driven by a unique circulating ion current. Here we demonstrate that SPARC-null mouse lenses exhibit abnormal circulation of fluid, ion, and small molecules which leads to altered fluorescein distribution in vivo, loss of resting membrane polarization, and altered distribution of small molecules. Microarray analysis of SPARC-null lenses showed changes in gene expression of ion channels and receptors, matrix and adhesion genes, cytoskeleton, immune response genes, and cell signaling molecules. Our results demonstrate that the regulation of SPARC on cell-capsular matrix interactions can influence the circulation of fluid and ions in the lens, and the phenotype in the SPARC-null mouse lens is the result of multiple intersecting pathways.
Project description:SPARC is a matricellular glycoprotein involved in regulation of the extracellular matrix, growth factors, adhesion, and migration. SPARC-null mice have altered basement membranes and develop posterior sub-capsular cataracts with cell swelling and equatorial vacuoles. Exchange of fluid, nutrients, and waste products in the avascular lens is driven by a unique circulating ion current. Here we demonstrate that SPARC-null mouse lenses exhibit abnormal circulation of fluid, ion, and small molecules which leads to altered fluorescein distribution in vivo, loss of resting membrane polarization, and altered distribution of small molecules. Microarray analysis of SPARC-null lenses showed changes in gene expression of ion channels and receptors, matrix and adhesion genes, cytoskeleton, immune response genes, and cell signaling molecules. Our results demonstrate that the regulation of SPARC on cell-capsular matrix interactions can influence the circulation of fluid and ions in the lens, and the phenotype in the SPARC-null mouse lens is the result of multiple intersecting pathways. Experiment Overall Design: Lens epithelial cells from 7 lenses of littermate mice were isolated by laser capture microdissection. 3 wild-type lenses from 3 different mice and 4 knock-out lenses from 3 different mice were used as biological replicates.
Project description:Comparative analysis of the transcriptome of 4T1 cells stably transduced with a lentiviral vector expressing a siRNA against murine SPARC (4T1-C18) with 4T1 control cells stably transduced with a lentiviral vector expressing a scramble sequence (4T1-SCR). Two-condition experiment, 4T1-C18 vs. 4T1-SCR cells. Biological replicates: 4 SPARC knock down, 4 control, independently grown in vitro and harvested. One replicate per array. Microarrays were hybridized in three different days.
Project description:We identified that Sparc gene expression is upregulated in corneal epithelial cells in a mouse model of dry eye disease involving lacrimal gland excision. Therefore, in this experiment we assess the effect of SPARC treatment on the transcriptome of human corneal epithelial cells.
Project description:Hepatocellular carcinoma (HCC), the most common type of primary liver cancer, is characterized as a highly aggressive tumor entity and has become a health challenge worldwide. Intracellular secreted protein acidic and rich in cysteine (SPARC) has been described as secreted protein that serves as paracrine mediator between cells extracellular matrix (ECM), however, its intracellular role remains unclear. Genetically modified HCC cell lines, cancer patient-derived organoids, and mouse models were used to analyze SPARC on metabolic processes, as well as the invasive behavior and sorafenib resistance of HCC cells. Transcriptome, interactome, and biochemical analyses were performed to study how SPARC regulate cholesterol homeostasis. High expression of intracellular SPARC was significantly associated with elevated cholesterol levels and an enhanced invasive phenotype in HCC. Our findings unveil a previously unrecognized interplay between SPARC and cholesterol homeostasis. Targeting SPARC-triggered cholesterol-dependent oncogenic signaling serves as a promising strategy for treating advanced HCC.