SignificanceExposure to high levels of particulate matter (PM) poses a major threat to human health. Cigarette smoke is the most common irritant that causes chronic obstructive pulmonary disease (COPD); however, at least one-fourth of patients with COPD are nonsmokers, and their disease is largely attributed to air pollution. The occurrence of pollution episodes in China has raised an emergent question of how PM leads to the pathogenesis of COPD. In this paper, we show that deregulation of mitochondrial NADH dehydrogenase gene expression levels plays a key role in the aggravation of COPD during air pollutant exposure, which can be rescued by taurine and 3-MA treatments in both mammalian cells and animals.

Recent studies have linked ambient fine particulate matter (PM2.5) to increased lung cancer mortality and morbidity. However, the underlying mechanism causing the adverse effects of PM2.5 is less clear. In the present study, post-transcriptional profiling was used to explore biological pathways involved in PM2.5-induced pulmonary disorders. The carcinogenesis and metastasis of PM2.5 exposure were evaluated by long-term PM2.5 exposure tests. We observed dysregulation of actin in A549 cells line and dysplasia in the lungs of mice exposed to PM2.5. Both PM2.5-exposed cells and animals showed increased Rnd3 expression levels. Moreover, miR-802 mimics rescued actin disorganization in vitro and alveolitis in vivo. Long-term exposure to PM2.5 promoted carcinogenesis and metastasis of pulmonary cells. Decreased miR-802 expression levels in the serum samples of PM2.5-treated mice and individuals from moderately polluted cities were observed. Increased Rnd3 expression levels in lung cancers tissues have been identified by a genome database TCGA, and have been linked to less overall survival probabilities of lung cancer patients. Our findings suggest that dysregulation of actin cytoskeleton and down-regulation of miR-802 expression might be the underlying mechanism involved in the adverse effects of PM2.5 exposure. In addition, long-term exposure to PM2.5 demonstrated strong associations with malignant pulmonary disorders.

Particulate matter (PM) exposure has been associated with intestinal disorders. Therefore, there is an urgent need to understand the precise molecular mechanism involved and explore potential prevention strategies. In this study, inhaled PM is shown to activate inflammatory pathways in murine colon. In a panel study, it is found that ambient PM levels are significantly associated with elevated number of fecal white blood cells in healthy subjects. Acting as a promoter, PM exposure accelerates chemical carcinogenesis‐induced colonic tumor formation in a murine model. Mechanistically, RNA‐seq assays suggest activation of phosphoinositide 3‐kinase (PI3K)/AKT cascades in chronically PM‐exposed human colon mucosal epithelial cells. Ablation of up‐stream driver fibroblast growth factor receptor 4 (FGFR4) effectively inhibits inflammation and neoplasia in PM‐exposed murine colons. Notably, dietary curcumin supplement is shown to protect against PM‐induced colonic injuries in mice. Collectively, these findings identify that PM exposure accelerates colonic tumorigenesis in a PI3K/AKT‐dependent manner and suggests potential nutrient supplement for prevention.

Myeloperoxidase () promoter SNPs rs2243828 (-764T>C) and rs2333227 (G-463A) program malignant phenotypes by regulating transcriptional activity. In this study, we enrolled a total of 1,175 controls and 1,078 patients with colorectal cancer with comprehensive clinical and survival information to assess whether these SNPs could affect the susceptibility and development of colorectal cancer. The rs2333227 TT genotype significantly increased the risk of colorectal cancer and decreased the overall survival time of patients. Colorectal cancer cells with the rs2333227 TT genotype exhibited enhanced proliferation, migration, and invasion capacity and Mechanistically, we found that SNP rs2333227 C to T mutation altered the binding affinity of the transcription factors AP-2α to the rs2333227 mutation region, sequentially enhancing expression levels of and activating further IL23A-MMP9 axis-mediated oncogenic signaling. Taken together, our findings indicate that SNP rs2333227 serves as a marker of enhanced risk for development of colorectal cancer. MPO polymorphisms are a guide for high risk and poor prognosis in patients colorectal cancer. .

Metals are vital toxic components of fine particulate matter (PM2.5). Cellular responses to exposure to PM2.5 or PM metal components remain unknown. Post-transcriptional profiling and subsequent cell- and individual-based assays implied that the metal ion-binding miR-4516/RPL37/autophagy pathway could play a critical role in cellular responses to PM2.5 and PM metal stresses. miR-4516 was up-regulated in A549 cells exposed to PM2.5 and in the serum of individuals living in a city with moderate air pollution. The expression levels of the miR-4516 target genes, namely, RPL37 and UBA52, were involved in ribosome function and inhibited by exposure to PM2.5 and PM metal components. Autophagy in A549 cells was induced by PM2.5 exposure as a response to decreased RPL37 expression. Moreover, enhanced miR-4516 expression was positively correlated with the augmentation of the internal burden of aluminum and lead in individuals living in a city with moderate air pollution. Hereby, the miR-4516/RPL37/autophagy pathway may represent a novel mechanism that mediates responses to PM metal components.