Project description:Chronic rhinosinusitis with nasal polyps (CRSwNP) is characterized by persistent symptoms associated to the development of nasal polyps. To this day, the molecular mechanisms involved are still not well defined. However, it has been suggested that a sustained inflammation as allergy is involved in its onset. In this pilot study, we aimed to look into the effect of the allergic status of the patient and in their underlying mechanisms. To achieve this, we recruited 22 patients with CRSwNP and classified them in non-allergic and allergic using ImmunoCAP ISAC molecular diagnosis. Plasma samples were analyzed using liquid chromatography coupled to mass spectrometry (LC-MS). Subsequently, the identified changed metabolites from plasma that were commercially available were then analyzed by targeted analysis in some nasal polyps. Additionally, nasal polyp and mucosa tissue samples were examined for eosinophils and neutrophils. We found that 9 out of the 22 patients were sensitized to some aeroallergens (named as allergic). The other 13 patients had no sensitizations (non-allergic). Regarding metabolomics, we found that bilirubin, cortisol, lysophosphatidylcholines (LPCs) 16:0, 18:0 and 20:4 and lysophosphatidylinositol (LPI) 20:4, metabolites that are usually related to a sustained allergic inflammation, were unexpectedly increased in the plasma of non-allergic patients with CRSwNP compared to allergic patients with CRSwNP. LPC 16:0, LPC 18:0 and LPI 20:4 metabolites followed the same trend in the nasal polyp as they did in plasma. Comparison of nasal polyps with nasal mucosa tissue showed a significant increase in eosinophils (p < 0.001) and neutrophils (p < 0.01) in allergic patients with CRSwNP. There were also more eosinophils in the polyps of non-allergic patients with CRSwNP than in their nasal mucosa (p <0.01). The polyps from non-allergic patients with CRSwNP had less eosinophils than the polyps of allergic patients with CRSwNP (p < 0.05). Our data suggests that there is a systemic inflammatory response associated to CRSwNP in the absence of allergy, which could be accountable for the nasal polyp development. Allergic patients with CRSwNP presented a higher number of eosinophils located in nasal polyps suggesting that eosinophilia might be connected to the development of nasal polyps in these patients.

Project description:Background: Alternative polyadenylation (APA) is emerging as a widespread mechanism of gene regulation. The usage of APA sites allows a single gene to encode multiple mRNA transcripts with different 3'-untranslated region (3'UTR) lengths. Many disease processes reflect the importance of the regulation of APA site switching. The objective of this study was to explore the profiling of tandem APA sites in nasal polyps compared with nasal uncinate process mucosa. Methods: Sequencing of APA sites (SAPAS) based on second-generation sequencing technology was undertaken to investigate the use of tandem APA sites and identify gene expression patterns in samples from the nasal polyps and nasal uncinate process mucosa of two patients with chronic rhinosinusitis with nasal polyps. The findings of the SAPAS analysis were validated via quantitative reverse-transcription polymerase chain reaction (qRT-PCR). Results: First, the results showed a switching of 3'UTR lengths in nasal polyps compared with nasal uncinate process mucosa. From the two patients, 105 overlapping genes in the nasal polyps were switched to distal poly(A) sites, and 90 such genes were switched to proximal poly(A) sites. Several Gene Ontology terms were enriched in the list of genes with switched APA sites, including transcription regulation, cell cycle, apoptosis, and metabolism. Second, we detected genes that showed differential expression with at least a 3-fold difference between nasal polyp tissue and nasal uncinate process mucosa. Between the two sample types, 627 genes exhibited differential expression. The qRT-PCR results confirmed our SAPAS results. Conclusion: APA site-switching events of 3'UTRs are prevalent in nasal polyp tissue, and the regulation of gene expression mediated by APA may play an important role in the formation and persistence of nasal polyps. Our results may provide new insights into the possible pathophysiologic processes involved in nasal polyps. Investigate the use of tandem APA sites of 3'ends of mRNAs using second-generation sequencing technology.

Dataset Information

Gene analysis of flagellin-treated nasal mucosa of Duox2-/- mice

Dataset's files

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets