Project description:This multi-center study will compare multi-target DNA and quantitative FIT stool-based testing to colonoscopy in individuals with Cystic Fibrosis (CF) undergoing colon cancer screening with colonoscopy. The primary endpoint is detection of any adenomas, including advanced adenomas and colorectal cancer (CRC).
Project description:Pseudomonas aeruginosa is a Gram-negative, opportunistic bacterium and a major etiological agent in monogenic disease cystic fibrosis (CF). High density colonies of P. aeruginosa are often isolated from hypoxic mucus plugs in respiratory tract of CF patients, indicating high adaptive capacities of the bacterium. Despite the high prevalence and related patient mortality, the protein machinery enabling the bacterium to adapt to this hypoxic environment remains to be fully elucidated. We investigated this by performing both SWATH mass spectrometry and data-dependent SPS-MS3 of TMT labelled peptides to profile the proteomes of two P. aeruginosa CF isolates, PASS2 and PASS3, and a laboratory reference strain, PAO1, grown under hypoxic stress (O2<1%) and aerobic conditions in media that mimics the nutrient components of the CF lung. 3,967 P. aeruginosa proteins were quantitated (FDR <1%) across all three strains, reflecting approximately 71% of predicted ORFs in PAO1 and representing the most comprehensive proteome of clinically relevant P. aeruginosa to date. Comparative analysis revealed 735, 640 and 364 proteins were altered by two-fold or more when comparing low oxygen to aerobic growth in PAO1, PASS2 and PASS3 respectively. Strikingly, under hypoxic stress, all strains showed concurrent increased abundance of proteins required for both aerobic (cbb3-1 and cbb3-2 terminal oxidases) and anaerobic denitrification and arginine fermentation, with the two clinical isolates showing higher relative expression of proteins in these pathways. Additionally, functional annotation revealed that clinical strains portray a unique expression profile of replication, membrane biogenesis and virulence proteins during hypoxia which may endow these bacteria with a survival advantage. These protein profiles illuminate the diversity of P. aeruginosa mechanisms to adapt to low oxygen and shows that CF isolates initiate a robust molecular response to persist under these conditions.
Project description:MicroRNAs are important negative regulators of protein coding gene expression, and have been studied intensively over the last few years. To this purpose, different measurement platforms to determine their RNA abundance levels in biological samples have been developed. In this study, we have systematically compared 12 commercially available microRNA expression platforms by measuring an identical set of 20 standardized positive and negative control samples, including human universal reference RNA, human brain RNA and titrations thereof, human serum samples, and synthetic spikes from homologous microRNA family members. We developed novel quality metrics in order to objectively assess platform performance of very different technologies such as small RNA sequencing, RT-qPCR and (microarray) hybridization. We assessed reproducibility, sensitivity, quantitative performance, and specificity. The results indicate that each method has its strengths and weaknesses, which helps guiding informed selection of a quantitative microRNA gene expression platform in function of particular study goals.
Project description:Cystic Fibrosis is a life limiting disease due to mutations in the Cystic Fibrosis Conductance Gene Regulator (CFTR). This is associated with a multiorgan disease combining pancreatic insufficiency, chronic infected bronchopathy and production of a salty sweat. Increased survival of patients leads to observation of new complications, including proximal tubule transport dysfunctions with increased output of glucose, amino acids, phosphate, calcium, uric acid, and low Molecular Weight proteins, which ultimately triggers tubulo-interstitial injury and chronic kidney disease. (Jouret et al. 2007) Exosomes are membrane vesicles stemming from Multi-Vesicular Bodies. They reflect the biological state of the cell they stem from because they incorporate various bioactive molecules from their cell of origin, which can be transferred to target cells. They are therefore ideal biomarkers for early diagnosis, prediction of disease progression or response to treatment. Urinary exosomes have been largely investigated in kidney or urothelial diseases and exosomal proteins proved to be biomarkers reflecting renal cellular biology. We hypothetized that urinary exosomal proteins might be differentially expressed, according to the presence of the mutation in the CFTR gene and its correction. We analyzed urinary exosomes of patients with CF and healthy controls based on their protein content determined by high resolution mass spectrometry, in combination with Gene Set Enrichment Analysis. These results were compared to those obtained in exosomes collected in patients treated with CFTR modulators.