Chlorinated Organophosphate Flame Retardants Impair the Lung Function via the IL-6/JAK/STAT Signaling Pathway.

Toxicological studies have revealed the adverse impacts of organophosphate flame retardants (OPFRs) on the respiratory system, while there is a lack of epidemiological evidence, and information for risk assessment remains insufficient. Herein, we investigated the associations of urinary metabolites of OPFRs with the lung function in 987 adults participating in the U.S. National Health and Nutrition Examination Survey 2011-2012. The elevation of three primary metabolites of chlorinated OPFRs [bis(1,3-dichloro-2-propyl) phosphate (BDCIPP), bis(2-chloroethyl) phosphate (BCEP), and bis(1-chloro-2-propyl) phosphate (BCIPP)] was related to pulmonary dysfunction in a sample-weighted regression model. Each one-unit increase in the log-transformed levels of BDCIPP and BCEP was related to 91.52 and 79.34 mL reductions in the forced vital capacity (FVC). Each one-unit elevation in BCIPP was correlated with 130.86, 153.56, 302.26, and 148.24 mL reductions in forced expiratory volume 1st second (FEV1), FVC, peak expiratory flow rate (PEF), and forced expiratory flow at 25-75% of FVC (FEF25-75%), respectively. Then, an adverse outcome pathway (AOP) framework was constructed using the Comparative Toxicogenomics Database, the Toxicity Forecaster, and the GeneCards database. Based on the weight of the evidence, BDCIPP, BCEP, BCIPP, and their parent compounds (TDCIPP, TCEP, and TCIPP) may affect the IL-6/Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway, induce airway remodeling, and impair the lung function. Additionally, tobacco smoke exposure may modify the effects of BDCIPP on the lung function (Pint < 0.05) and affect the IL-6-mediated AOP. These results suggested that chlorinated OPFRs were associated with pulmonary dysfunction via the IL-6/JAK/STAT pathway.

Biomineralized MnO2 Nanoplatforms Mediated Delivery of Immune Checkpoint Inhibitors with STING Pathway Activation to Potentiate Cancer Radio-Immunotherapy.

Radiotherapy (RT), as one of the main methods in the clinical treatment of various malignant tumors, would induce systemic immunotherapeutic effects by triggering immunogenic cell death (ICD) of cancer cells. However, the antitumor immune responses produced by RT-induced ICD alone usually are not robust enough to eliminate distant tumors and thus ineffective against cancer metastases. Herein, a biomimetic mineralization method for facile synthesis of MnO2 nanoparticles with high anti-programmed death ligand 1 (αPDL1) encapsulation efficiency (αPDL1@MnO2) is proposed to reinforce RT-induced systemic antitumor immune responses. This therapeutic nanoplatforms-mediated RT can significantly improve the killing of tumor cells and effectively evoke ICD by overcoming hypoxia-induced radio-resistance and reprogramming the immunosuppressive tumor microenvironment (TME). Furthermore, the released Mn2+ ions from αPDL1@MnO2 under acidic tumor pH can activate the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway and facilitate the dendritic cells (DCs) maturation. Meanwhile, αPDL1 released from αPDL1@MnO2 nanoparticles would further promote the intratumoral infiltration of cytotoxic T lymphocytes (CTLs) and trigger systemic antitumor responses, resulting in a strong abscopal effect to effectively inhibit tumor metastases. Overall, the biomineralized MnO2-based nanoplatforms offer a simple strategy for TME modulation and immune activation, which are promising for enhanced RT immunotherapy.

Reactive Oxygen Species-Triggered Curcumin Release from Hollow Mesoporous Silica Nanoparticles for PM2.5-Induced Acute Lung Injury Treatment.

Exposure to fine particulate matter with a diameter ≤2.5 µm (PM2.5) can result in serious inflammation and oxidative stress in lung tissue. However, there is presently very few effective treatments for PM2.5-induced many pulmonary diseases, such as acute lung injury (ALI). Herein, curcumin-loaded reactive oxygen species (ROS)-responsive hollow mesoporous silica nanoparticles (Cur@HMSN-BSA) are proposed for scavenging the intracellular ROS and suppressing inflammatory responses against PM2.5-induced ALI. The prepared nanoparticles were coated with bovine serum albumin (BSA) via an ROS-sensitive thioketal (TK)-containing linker, in which the TK-containing linker would be cleaved by the excessive amounts of ROS in inflammatory sites to induce the detachment of BSA from the nanoparticles surface and thus triggering release of loaded curcumin. The Cur@HMSN-BSA nanoparticles could be used as ROS scavengers because of their excellent ROS-responsiveness, which were able to efficiently consume high concentrations of intracellular ROS. Furthermore, it was also found that Cur@HMSN-BSA downregulated the secretion of several important pro-inflammatory cytokines and promoted the polarization from M1 phenotypic macrophages to M2 phenotypic macrophages for eliminating PM2.5-induced inflammatory activation. Therefore, this work provided a promising strategy to synergistically scavenge intracellular ROS and suppress the inflammation responses, which may serve as an ideal therapeutic platform for pneumonia treatment.

linc01515 regulates PM2.5-induced oxidative stress via targeting NRF2 in airway epithelial cells.

Dysregulation of long non-coding RNAs (lncRNAs) is involved in the adverse effects caused by fine particulate matter (PM2.5). However, the molecular mechanism is not fully clarified. In this study, we performed lncRNA sequencing on PM2.5-treated human bronchial epithelial (HBE) cells to identify vital lncRNAs, and verified the differential expression of the lncRNAs by RT-qPCR in HBE and human normal lung epithelial (BEAS-2B) cells. A total of 657 and 652 lncRNAs were dysregulated after exposure to 125 and 250 µg/mL of PM2.5, respectively. Of these, lncRNA linc01515 was upregulated in HBE and BEAS-2B cells with PM2.5 treatment. Subcellular localization experiments showed that linc01515 was mostly localized in the nucleus. Functionally, we downregulated the expression of linc01515 in HBE and BEAS-2B cells before PM2.5 treatment, which can decrease malonydialdehyde (MDA) and reactive oxygen species (ROS) levels, and improve superoxide dismutase (SOD) activity. Correspondingly, linc01515 overexpression enhanced PM2.5-induced oxidative injury in airway epithelial cells. Mechanistically, N6-methyladenosine RNA binding protein immunoprecipitation (MeRIP) assay showed that the enrichment level of m6A on linc01515 was increased after PM2.5 treatment, and the m6A modification level and expression of linc01515 was decreased in the HBE cells with 3-deazaadenosine (DAA) treatment or knockdown of METTL3 to inhibit the RNA methylation level. Western blot found that NRF2, a vital transcription factor, was enhanced remarkably in linc01515-silenced cells and decreased in linc01515-overexpressed cells. Furthermore, inhibition of NRF2 activity significantly rescued effect of downregulated linc01515 expression on PM2.5-induced cytotoxicity. In addition, we observed the similar effect when downregulating linc01515 and NRF2 expression in HBE and BEAS-2B cells before PM2.5 treatment. Taken together, our findings demonstrated that PM2.5 treatment may upregulate the expression of linc01515 by enhancing its m6A modification, and then regulate NRF2 to induce oxidative damage of airway epithelial cells.

LncRNA BCLET variant confers bladder cancer susceptibility through alternative splicing of MSANTD2 exon 1.

BACKGROUND: Alternative splicing (AS)-related single nucleotide polymorphisms (SNPs) are associated with risk of cancers, but the potential mechanism has not been fully elucidated. METHODS: Two-stage case-control studies comprising 1630 cases and 2504 controls were conducted to investigate the association between the AS-SNPs and bladder cancer susceptibility. A series of assays were used to evaluate the functional effect of AS-SNPs on bladder cancer risk. RESULTS: We observed that SNP rs558814 A>G located in lncRNA BCLET (Bladder Cancer Low-Expressed Transcript, ENSG00000245498) can decrease the risk of bladder cancer (odds ratio [OR] = 0.84, 95% confidence interval [CI] = 0.76-0.92, p = 3.26 × 10-4 ). Additionally, the G allele of rs558814 had transcriptional regulatory effects and facilitated the expression of BCLET transcripts, including BCLET-long and BCLET-short. We also found decreased BCLET expression in bladder cancer tissues and cells, and BCLET transcript upregulation substantially inhibited tumor growth of both bladder cancer cells and xenograft models. Mechanistically, BCLET recognized and regulated AS of MSANTD2 to participate in bladder carcinogenesis, preferentially promoting the production of MSANTD2-004. CONCLUSIONS: SNP rs558814 was associated with the expression of BCLET, which mainly increased the expression of MSANTD2-004 through AS of MSANTD2.