Project description:Normal epithelium exists within a dynamic extracellular matrix (ECM) that is tuned to regulate tissue specific epithelial cell function. As such, ECM contributes to tissue homeostasis, differentiation, and disease, including cancer. Though it is now recognized that the functional unit of normal and transformed epithelium is the epithelial cell and its adjacent ECM, we lack a basic understanding of tissue-specific ECM composition and abundance, as well as how physiologic changes in ECM impact cancer risk and outcomes. While traditional proteomic techniques have advanced to robustly identify ECM proteins within tissues, methods to determine absolute abundance have lagged. Here, with a focus on tissues relevant to breast cancer, we utilize mass spectrometry methods optimized for absolute quantitative ECM analysis. Employing an extensive protein extraction and digestion method, combined with stable isotope labeled Quantitative conCATamer (QconCAT) peptides that serve as internal standards for absolute quantification of protein, we quantify 98 ECM, ECM-associated, and cellular proteins in a single analytical run. In rodent models, we applied this approach to the primary site of breast cancer, the normal mammary gland, as well as a common and particularly deadly site of breast cancer metastasis, the liver. We find that mammary gland and liver have distinct ECM abundance and relative composition. Further, we show mammary gland ECM abundance and relative compositions differ across the reproductive cycle, with the most dramatic changes occurring during the pro-tumorigenic window of weaning-induced involution. Combined, this work suggests ECM candidates for investigation of breast cancer progression and metastasis, particularly in postpartum breast cancers that are characterized by high metastatic rates. Finally, we suggest that with use of absolute quantitative ECM proteomics to characterize tissues of interest, it will be possible to reconstruct more relevant in vitro models to investigate tumor-ECM dynamics at higher resolution.
Project description:Younger age and obesity increase the incidence and rates of metastasis of triple-negative breast cancer (TNBC), an aggressive subtype of breast cancer. The tissue microenvironment, specifically the extracellular matrix (ECM), is known to promote tumor invasion and metastasis. We sought to characterize the effect of both age and obesity on the ECM of liver tissue. We used a diet-induced obesity (DIO) model where 10-week-old female mice were fed a high-fat diet (HFD) for 12 weeks or a control chow diet (CD) where time points were every 4 weeks to monitor age and obesity. We isolated liver tissue to characterize the ECM at each time point. Utilizing proteomics, we found that the early stages of obesity were sufficient to induce distinct differences in the ECM composition of the livers. ECM proteins previously implicated in TNBC invasion, Collagen V and Collagen IV, were enriched with weight gain. Together these data implicate ECM changes in the primary tumor microenvironment as mechanisms by which age and obesity contribute to breast cancer progression.
Project description:INTRODUCTION AND OBJECTIVE: Loss of renal function is often the impetus for operative intervention in renal obstruction. Obstructive nephropathy is characterized discrete morphological and physiologic changes including tubular dilatation, apoptosis, and atrophy, as well as interstitial cellular infiltration and progressive interstitial fibrosis. We hypothesize that there are gene expression alterations correlated with obstructive nephropathy that could serve as biomarkers for early intervention. METHODS: C57BL/6 mice were subjected to Unilateral Urethral Obstruction (UUO) or sham surgery at postnatal day 21 of life, and kidneys were harvested after 1, 2, 5 and 9 days postoperatively. RNA was extracted from kidneys and comprehensive gene expression profiling was performed with Agilent microarrays. We used biological replicates: 13 UUO replicates, 9 sham replicates. 2-Channel microarrays were hybridized using universal reference in the Cy3 channel. Ingenuity pathway analysis was used to analyze the biological function and gene networks of gene expression data. RESULTS: Microarray analysis revealed more than 1800 transcripts that were up- or down-regulated over days 1 through 9 following obstruction, and included many transcripts reported previously (FOS, CD44, CLU, SPP1 and EGF). Pathway analysis revealed significant enrichment of transcripts in cell activation/differentiation, immune/inflammatory responses, cell cycle, metabolic process and transport. Interestingly, IPA network analysis showed that transcriptional regulatory pathway involving CEBPB/HNF4A is involved in obstructive nephropathy. CONCLUSIONS: Transcript profiling identified numerous gene expression changes following UUO and suggests a role for CEBPB/HNF4A pathway in obstructive nephropathy. This dataset provides a foundation for development of biomarkers for obstructive nephropathy. Time: day samples were collected post operation Somatic Modification: mice were operated on to generate urethral obstruction (Obstructed/Control) time_series_design
Project description:Aging is a risk factor for adipose tissue dysfunction, which is associated with inflammatory innate immune mechanisms. Since the adipose tissue/liver axis contributes to hepatosteatosis, we sought to determine age-related adipose tissue dysfunction in the context of the activation of the innate immune system fostering fatty liver phenotypes. Using wildtype and immune-deficient mice, we compared visceral adipose tissue and liver mass as well as hepatic lipid storage in young (ca. 14 weeks) and adult (ca. 30 weeks) mice. Adipocyte size was determined as an indicator of adipocyte function and liver steatosis was quantified by hepatic lipid content. Further, lipid storage was investigated under normal and steatosis-inducing culture conditions in isolated hepatocytes. The physiological age-related increase in body weight was associated with a disproportionate increase in adipose tissue mass in immune-deficient mice, which coincided with higher triglyceride storage in the liver. Lipid storage was similar in isolated hepatocytes from wildtype and immune-deficient mice under normal culture conditions but was significantly higher in immune-deficient than in wildtype hepatocytes under steatosis-inducing culture conditions. Immune-deficient mice also displayed increased inflammatory, adipogenic, and lipogenic markers in serum and adipose tissue. Thus, the age-related increase in body weight coincided with an increase in adipose tissue mass and hepatic steatosis. In association with a (pro-)inflammatory milieu, aging thus promotes hepatosteatosis, especially in immune-deficient mice.
Project description:Based on the work flow of quantitative proteomic analysis combined with TMT labeling and liquid chromatography-tandem mass spectrometry (LC-MS/MS), this study carried out quantitative proteomic analysis on the liver tissues of Tibetan pigs and Yorkshire pigs in Shannan (about 4000 m), Linzhi (about 3000 m) and Jiuzhaigou (about 1500 m), and compared the differences of protein mass spectra between the liver of living pigs at three altitudes.
Project description:Cancer metastasis risk increases in older individuals, but the mechanisms for this risk increase are unclear. Many peritoneal cancers, including ovarian cancer, preferentially metastasize to peritoneal fat depots. However, there is a dearth of studies exploring aged peritoneal adipose tissue in the context of cancer. Because adipose tissue produces signals which influence several diseases including cancer, proteomics of adipose tissue in aged and young mice may provide insight into metastatic mechanisms. We analyzed mesenteric, omental, and uterine adipose tissue groups from the peritoneal cavities of young and aged C57BL/6J mouse cohorts with a low-fraction SDS-PAGE gelLC-MS/MS method. We identified 2308 protein groups and quantified 2167 groups, among which several protein groups showed twofold or greater abundance differences between the aged and young cohorts. Cancer-related gene products previously identified as significant in another age-related study were found altered in this study. Several gene products known to suppress proliferation and cellular invasion were found downregulated in the aged cohort, including R-Ras, Arid1a, and heat shock protein β1. In addition, multiple protein groups were identified within single cohorts, including the proteins Cd11a, Stat3, and Ptk2b. These data suggest that adipose tissue is a strong candidate for analysis to identify possible contributors to cancer metastasis in older subjects. The results of this study, the first of its kind using uterine adipose tissue, contribute to the understanding of the role of adipose tissue in age-related alteration of oncogenic pathways, which may help elucidate the mechanisms of increased metastatic tumor burden in the aged. Graphical abstract We analyzed mesenteric, omental, and uterine adipose tissue groups from the peritoneal cavities of young and aged C57BL/6J mouse cohorts with a low-fraction SDS-PAGE gelLC-MS/MS method. These fat depots are preferential sites for many peritoneal cancers. The results of this study, the first of its kind using uterine adipose tissue, contribute to the understanding of the role of adipose tissue in age-related alteration of oncogenic pathways, which may help elucidate the mechanisms of increased metastatic tumor burden in the aged.
Project description:Nonalcoholic fatty liver disease, a condition in which excess fat accumulates in the liver, is strongly associated with the metabolic syndrome, including obesity and other related conditions. This disease has the potential to progress from steatosis to steatohepatitis, fibrosis, and cirrhosis. The recent increase in the prevalence of the metabolic syndrome is largely driven by changes in diet and activity levels. Individual variation in the response to this obesogenic environment, however, is attributable in part to genetic variation between individuals, but very few mammalian genetic loci have been identified with effects on fat accumulation in the liver. To study the genetic basis for variation in liver fat content in response to dietary fat, liver fat proportion was determined using quantitative magnetic resonance imaging in 478 mice from 16 LG/J X SM/J recombinant inbred strains fed either a high-fat (42% kcal from fat) or low-fat (15% kcal from fat) diet. An analysis of variance confirmed that there is a genetic basis for variation in liver fat content within the population with significant effects of sex and diet. Three quantitative trail loci that contribute to liver fat content also were mapped.