Resolution of late-onset asthma following high-dose chemotherapy

Exploration and Validation of Potential Biomarkers and Therapeutic Targets in Ferroptosis of Asthma

Purpose

Asthma is a chronic inflammatory airway disease involving multiple mechanisms, of which ferroptosis is a form of programmed cell death. Recent studies have shown that ferroptosis may play a crucial role in the pathogenesis of asthma, but no specific ferroptosis gene has been found in asthma, and the exact mechanism is still unclear. The present study aimed to screen ferroptosis genes associated with asthma and find therapeutic targets, in order to contribute a new clue for the diagnosis and therapy of asthma.

Methods

Ferroptosis-related differentially expressed genes (FR-DEGs) in asthma were selected by the GSE41861, GSE43696 and ferroptosis datasets. Next, the FR-DEGs were subjected by GO and KEGG enrichment, and the mRNA-miRNA network was constructed. Then, GSEA and GSVA enrichment analysis and Immune infiltration analysis were performed, followed by targeted drug prediction. Finally, the expression of FR-DEGs was confirmed using GSE63142 dataset and RT-PCR assay.

Results

We found 13 FR-DEGs by the GSE41861, GSE43696 and ferroptosis database. Functional enrichment analysis revealed that the 13 FR-DEGs were enriched in oxidative stress, immune response, ferroptosis, lysosome, necrosis, apoptosis etc. Moreover, our results revealed the mRNA-miRNA network of the FR-DEGs and identified candidate drugs. Also, immune infiltration revealed that ELAVL1, CREB5, CBR1 and NR1D2 are associated with the immune cells and may be potential targets in asthma. Finally, 10 FR-DEGs were validated by the GSE63142 database. It was verified that 7 FR-DEGs were differentially expressed by collecting asthma patients and healthy controls.

Conclusion

This study ultimately identified 7 FR-DEGs for the diagnosis and therapy of asthma. These 7 FR-DEGs contribute to oxidative stress and immune responses. This study provides potential therapeutic targets and biomarkers for asthma patients, shedding further light on the pathogenesis of asthma as well as providing new insights into the treatment of asthma.

A review on the pathophysiology of asthma remission

Asthma is a chronic respiratory condition, which is highly prevalent worldwide. Although no cure is currently available, it is well recognized that some asthma patients can spontaneously enter remission of the disease later in life. Asthma remission is characterized by absence of symptoms and lack of asthma-medication use. Subjects in asthma remission can be divided into two groups: those in clinical remission and those in complete remission. In clinical asthma remission, subjects still have a degree of lung functional impairment or bronchial hyperresponsiveness, while in complete asthma remission, these features are no longer present. Over longer periods, the latter group is less likely to relapse. This remission group is of great scientific interest due to the higher potential to find biomarkers or biological pathways that elicit or are associated with asthma remission. Despite the fact that the definition of asthma remission varies between studies, some factors are reproducibly observed to be associated with remitted asthma. Among these are lower levels of inflammatory markers, which are lowest in complete remission. Additionally, in both groups some degree of airway remodeling is present. Still, the pathological disease state of asthma remission has been poorly investigated. Future research should focus on at least two aspects: further characterisation of the small airways and airway walls in order to determine histologically true remission, and more thorough biological pathway analyses to explore triggers that elicit this phenomenon. Ultimately, this will result in pharmacological targets that provide the potential to steer the course of asthma towards remission.

Airway reactivity in children before and after stem cell transplantation

Stem cell transplantation (SCT) is associated with pulmonary complications. We encountered several children post-SCT with a clinical picture suggestive of airway hyper-reactivity (AHR) and evidence of reversible airway obstruction that was not reported pre-transplant.We evaluated the possibility of increased AHR as assessed by methacholine challenge test (MCT) following the course of SCT, and assessed a possible correlation between AHR and pulmonary complications.This was a prospective study evaluating consecutive patients referred for SCT to the Department of Pediatric Hemato-Oncology. Evaluation included pulmonary function test and MCT before and after SCT, and assessment of pulmonary complications.Twenty-one of 33 patients completed the study. The mean PC(20) was 14.3 +/- 4.1 mg/ml prior to SCT; afterward the mean PC(20) decreased to 11.2 +/- 5.6 mg/ml (P = 0.018). The number of patients with airway reactivity (PC(20) < or = 8 mg/ml) increased from 2/21 patients before SCT to 8/21 patients after SCT (P = 0.043; McNemar test with Yates correction). Pulmonary complications and hospitalization were recorded in 33.3% of the patients (7/21 patients): 62.5% of the patients (5 patients) with AHR compared to 15.4% (2 patients) in the group without AHR (P = 0.041; Fisher exact test). There were 10 hospitalizations among the 8 patients with positive MCT compared to 2 hospitalizations in 13 patients with negative MCT (median 1 vs. 0, P = 0.045; Mann-Whitney U-test).Increased airway reactivity was observed in our study following the course of SCT. Positive MCT after SCT may be associated with increased risk of pulmonary complications. Larger prospective studies are needed to evaluate the possible mechanisms responsible for increased AHR and the clinical importance of these findings.