Long-term exposure to house dust mites accelerates lung cancer development in mice

Dynamic characteristics of metabolism and small extracellular vesicles during malignant transformation of BEAS-2B cells induced by coal tar pitch extract

Lung cancer poses a significant global burden with rising morbidity and mortality. Coal tar pitch-induced lung cancer is an occupational disease where early detection is crucial but challenging due to unclear pathogenesis. We established a malignant transformation model using BEAS-2B cells treated with coal tar pitch extract (CTPE). Macro- and micro-observations showed CTPE-induced alterations, including changes in cell morphology, enhanced proliferation and migration abilities, upregulated EGFR expression, modified levels of CYP1A1 and GSTM1 metabolizing enzymes, and a transition towards a mesenchymal phenotype. These findings strongly suggest that the cells have undergone malignant transformation. Metabolomics analysis revealed changes in 1120 metabolites, with 31 co-expressed, mainly in energy and amino acid metabolism. Small extracellular vesicles (SEVs) concentrations and EGFR levels were significantly altered. Correlation analysis identified a relationship between these biomarkers, implying their potential significance as early events in the initiation and progression of lung cancer. These findings provide valuable insights and a rationale for lung cancer screening and mechanistic investigations, thereby contributing to a deeper understanding of the disease.

Differential gene expression in PBMCs: Insights into the mechanism how pulmonary tuberculosis increases lung cancer risk

Pre-existing of pulmonary tuberculosis (PTB) poses increased lung cancer risk, yet the molecular mechanisms remain inadequately understood. This study sought to elucidate the potential mechanisms by performing comprehensive analyses of differentially expressed genes (DEGs) in peripheral blood mononuclear cells (PBMCs) from patients with PTB, lung adenocarcinoma (LUAD), and lung squamous cell carcinoma (LUSC). Microarray assays were employed to analyze the DEGs in PBMCs of these patients. The analyses revealed that, compared to healthy controls, the number of differentially expressed LncRNA in PBMCs from patients with PTB, LUAD, and LUSC were 801, 8,541, and 7,796, respectively. Similarly, the differentially expressed mRNA in PBMCs from patients with PTB, LUAD, and LUSC were 629, 4,865, and 4,438, respectively. These differentially expressed transcripts represent significant resources for the identifying diagnostic and differential diagnostic biomarkers for lung cancer and PTB. Pathways enriched by dysregulated mRNAs in patients with PTB, LUAD, and LUSC were identified through GO and KEGG pathway analyses. The results indicated that 9 pathways including the NOD-like receptor signaling pathway, pathways in cancer, and the MAPK signaling pathway were co-enriched across the PTB, LUAD, and LUSC groups, providing insights into the mechanisms by which PTB may increase the risk of cancer development and progression.

House dust mite-induced asthma exacerbates Alzheimer's disease changes in the brain of the AppNL-G-F mouse model of disease

Alzheimer's disease (AD) is an age-related neurodegenerative disorder characterized by the accumulation of amyloid-β (Aβ) plaques, neuroinflammation, and neuronal death. Besides aging, various comorbidities increase the risk of AD, including obesity, diabetes, and allergic asthma. Epidemiological studies have reported a 2.17-fold higher risk of dementia in asthmatic patients. However, the molecular mechanism(s) underlying this asthma-associated AD exacerbation is unknown. This study was designed to explore house dust mite (HDM)-induced asthma effects on AD-related brain changes using the AppNL-G-F transgenic mouse model of disease. Male and female 8-9 months old C57BL/6J wild type and AppNL-G-F mice were exposed to no treatment, saline sham, or HDM extract every alternate day for 16 weeks for comparison across genotypes and treatment. Mice were euthanized at the end of the experiment, and broncho-alveolar lavage fluid (BALF), blood, lungs, and brains were collected. BALF was used to quantify immune cell phenotype, cytokine levels, total protein content, lactate dehydrogenase (LDH) activity, and total IgE. Lungs were sectioned and stained with hematoxylin and eosin, Alcian blue, and Masson's trichrome. Serum levels of cytokines and soluble Aβ1-40/42 were quantified. Brains were sectioned and immunostained for Aβ, GFAP, CD68, and collagen IV. Finally, frozen hippocampi and temporal cortices were used to perform Aβ ELISAs and cytokine arrays, respectively. HDM exposure led to increased levels of inflammatory cells, cytokines, total protein content, LDH activity, and total IgE in the BALF, as well as increased pulmonary mucus and collagen staining in both sexes and genotypes. Levels of serum cytokines increased in all HDM-exposed groups. Serum from the AppNL-G-F HDM-induced asthma group also had significantly increased soluble Aβ1-42 levels in both sexes. In agreement with this peripheral change, hippocampi from asthma-induced male and female AppNL-G-F mice demonstrated elevated Aβ plaque load and increased soluble Aβ 1-40/42 and insoluble Aβ 1-40 levels. HDM exposure also increased astrogliosis and microgliosis in both sexes of AppNL-G-F mice, as indicated by GFAP and CD68 immunoreactivity, respectively. Additionally, HDM exposure elevated cortical levels of several cytokines in both sexes and genotypes. Finally, HDM-exposed groups also showed a disturbed blood-brain-barrier (BBB) integrity in the hippocampus of AppNL-G-F mice, as indicated by decreased collagen IV immunoreactivity. HDM exposure was responsible for an asthma-like condition in the lungs that exacerbated Aβ pathology, astrogliosis, microgliosis, and cytokine changes in the brains of male and female AppNL-G-F mice that correlated with reduced BBB integrity. Defining mechanisms of asthma effects on the brain may identify novel therapeutic targets for asthma and AD.