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Exposure to fine particulate matter (PM2.5), of which secondary organic aerosol (SOA) is a major constituent, is linked to adverse health outcomes, including cardiovascular disease, lung cancer, and preterm birth. Atmospheric oxidation of isoprene, the most abundant nonmethane hydrocarbon emitted into Earth's atmosphere primarily from vegetation, contributes to SOA formation. Isoprene-derived SOA has previously been found to alter inflammatory/oxidative stress genes. MicroRNAs (miRNAs) are epigenetic regulators that serve as post-transcriptional modifiers and key mediators of gene expression. To assess whether isoprene-derived SOA alters miRNA expression, BEAS-2B lung cells were exposed to laboratory-generated isoprene-derived SOA constituents derived from the acid-driven multiphase chemistry of authentic methacrylic acid epoxide (MAE) or isomeric isoprene epoxydiols (IEPOX) with acidic sulfate aerosol particles. These IEPOX- and MAE-derived SOA constituents have been shown to be measured in large quantities within PM2.5 collected from isoprene-rich areas affected by acidic sulfate aerosol particles derived from human activities. A total of 29 miRNAs were identified as differentially expressed when exposed to IEPOX-derived SOA and 2 when exposed to MAE-derived SOA, a number of which are inflammatory/oxidative stress associated. These results suggest that miRNAs may modulate the inflammatory/oxidative stress response to SOA exposure, thereby advancing the understanding of airway cell epigenetic response to SOA.

Acid-driven multiphase chemistry of isoprene epoxydiols (IEPOX), key isoprene oxidation products, with inorganic sulfate aerosol yields substantial amounts of secondary organic aerosol (SOA) through the formation of organosulfur compounds. The extent and implications of inorganic-to-organic sulfate conversion, however, are unknown. In this article, we demonstrate that extensive consumption of inorganic sulfate occurs, which increases with the IEPOX-to-inorganic sulfate concentration ratio (IEPOX/Sulfinorg), as determined by laboratory measurements. Characterization of the total sulfur aerosol observed at Look Rock, Tennessee, from 2007 to 2016 shows that organosulfur mass fractions will likely continue to increase with ongoing declines in anthropogenic Sulfinorg, consistent with our laboratory findings. We further demonstrate that organosulfur compounds greatly modify critical aerosol properties, such as acidity, morphology, viscosity, and phase state. These new mechanistic insights demonstrate that changes in SO2 emissions, especially in isoprene-dominated environments, will significantly alter biogenic SOA physicochemical properties. Consequently, IEPOX/Sulfinorg will play an important role in understanding the historical climate and determining future impacts of biogenic SOA on the global climate and air quality.

Objective: Lung cancer, as a prevalent malignancy, continues to be a considerable clinical challenge. This study aimed to elucidate the role of microRNA-5703 (miR-5703) in lung cancer progression and to assess the effect of exosomal miR-5703 on tumor-associated endothelial cells (TAECs). Material and Methods: We analyzed Gene Expression Omnibus datasets and performed quantitative real-time polymerase chain reaction to determine miR-5703 expression levels in lung cancer tissues. Exosomes derived from lung cancer cells were identified, and the effects of miR-5703 inhibitors or mimics on malignant biological behavior were evaluated in the lung cancer cells. Moreover, to understand these effects on TAECs, we assessed angiogenesis, endothelial–mesenchymal transition (EndMT), and barrier function after treatment with miR- 5703 inhibitors or the exosome-assimilated inhibitor cytochalasin D. Tumor-bearing mouse models were used in validating the tumor-promoting effects of exosomes derived from lung cancer cells, and the markers of angiogenesis, EndMT, and barrier function were examined. Results: Our results showed that miR-5703 was up-regulated in the lung cancer cells and patient-derived exosomes. miR-5703 facilitated cell growth, migration, invasion, in LC cells, and impaired the barrier function, which promoted angiogenesis and EndMT of TAECs by carrying in exosomes through targeting inhibitor of growth family member 4 (ING4) was identified as target of miR-5703 (P < 0.05). In vivo , the tumor-promoting effects of lung cancer cell–derived exosomes were rescued by miR-5703 inhibitors, leading to the up-regulation of ING4 expression and reduction in vascular distribution in the tumor tissues (P < 0.05). Conclusion: miR-5703 operates as an oncogenic factor in lung cancer. After being taken up by TAECs, exosomal miR-5703 promotes angiogenesis, EndMT, and barrier damage by targeting ING4. Hence, miR-5703 is a potential target in the lung cancer microenvironment. [ABSTRACT FROM AUTHOR]

Immunotherapy has brought significant advancements in the treatment of lung adenocarcinoma (LUAD), but identifying suitable candidates remains challenging. In this study, we investigated tumour cell heterogeneity using extensive single‐cell data and explored the impact of different tumour cell cluster abundances on immunotherapy in the POPLAR and OAK immunotherapy cohorts. Notably, we found a significant correlation between CKS1B+ tumour cell abundance and treatment response, as well as stemness potential. Leveraging marker genes from the CKS1B+ tumour cell cluster, we employed machine learning algorithms to establish a prognostic and immunotherapeutic signature (PIS) for LUAD. In multiple cohorts, PIS outperformed 144 previously published signatures in predicting LUAD prognosis. Importantly, PIS reliably predicted genomic alterations, chemotherapy sensitivity and immunotherapy responses. Immunohistochemistry validated lower expression of immune markers in the low‐PIS group, while in vitro experiments underscored the role of the key gene PSMB7 in LUAD progression. In conclusion, PIS represents a novel biomarker facilitating the selection of suitable LUAD patients for immunotherapy, ultimately improving prognosis and guiding clinical decisions. [ABSTRACT FROM AUTHOR]

Background: Thymoma is a primary tumor of the thymus, commonly located in the anterior mediastinum. Most thymomas are benign or low‐grade malignant, but they can invade surrounding organs or metastasize. The primary treatment for thymoma is surgical resection. Traditional methods involve open thoracotomy, but it is traumatic, with slow recovery and many complications. In recent years, with the development of thoracoscopic techniques, thoracoscopic total thymectomy has gradually become the preferred method for small size thymomas due to its minimally invasive, safe, and effective. Methods: This paper introduces a thoracoscopic extend thymectomy technique, the subxiphoid video–assisted thoracoscopic extend thymectomy with sternal suspension. This method involves placing hooks at the upper and lower ends of the sternum to suspend the sternum upward, increasing the thoracic cavity space and facilitating thoracoscopic operations. This research reviews the clinical data of 59 patients with early‐stage thymomas treated with this technique at our center since 2020 and analyzes the perioperative therapeutic efficacy and safety. It also compares the outcomes with those of 17 patients who underwent thoracoscopic approaches. Results: The results show that subxiphoid video–assisted thoracoscopic total thymectomy with sternal suspension is an innovative and effective surgical method, achieving the same tumor eradication as other thoracic surgeries. The flexible switching of observation ports provides a more comprehensive surgical field, reduces surgical trauma and complications, and improves the surgical outcomes and quality of life for patients. [ABSTRACT FROM AUTHOR]

Lung adenocarcinoma (LUAD) generally presents as an immunosuppressive microenvironment. The characteristics of cell‐to‐cell communication in the LUAD microenvironment has been unclear. In this study, the LUAD bulk RNA‐seq data and single‐cell RNA‐seq data were retrieved from public dataset. Differential expression genes (DEGs) between LUAD tumor and adjacent non‐tumor tissues were calculated by limma algorithm, and then detected by PPI, KEGG, and GO analysis. Cell–cell interactions were explored using the single‐cell RNA‐seq data. Finally, the first 15 CytoHubba genes were used to establish related pathways and these pathways were used to characterize the immune‐related ligands and their receptors in LUAD. Our analyses showed that monocytes or macrophages interact with tissue stem cells and NK cells via SPP1 signaling pathway and tissue stem cells interact with T and B cells via CXCL signaling pathway in different states. Hub genes of SPP1 participated in SPP1 signaling pathway, which was negatively correlated with CD4+ T cell and CD8+ T cell. The expression of SPP1 in LUAD tumor tissues was negatively correlated with the prognosis. While CXCL12 participated in CXCL signaling pathway, which was positively correlated with CD4+ T cell and CD8+ T cell. The role of CXCL12 in LUAD tumor tissues exhibits an opposite effect to that of SPP1. This study reveals that tumor‐associated monocytes or macrophages may affect tumor progression. Moreover, the SPP1 and CXCL12 may be the critic genes of cell‐to‐cell communication in LUAD, and targeting these pathways may provide a new molecular mechanism for the treatment of LUAD. [ABSTRACT FROM AUTHOR]

Background: The hypothesized link between low‐density lipoprotein (LDL) and oncogenesis has garnered significant interest, yet its explicit impact on lung adenocarcinoma (LUAD) remains to be elucidated. This investigation aims to demystify the function of LDL‐related genes (LRGs) within LUAD, endeavoring to shed light on the complex interplay between LDL and carcinogenesis. Methods: Leveraging single‐cell transcriptomics, we examined the role of LRGs within the tumor microenvironment (TME). The expression patterns of LRGs across diverse cellular phenotypes were delineated using an array of computational methodologies, including AUCell, UCell, singscore, ssGSEA, and AddModuleScore. CellChat facilitated the exploration of distinct cellular interactions within LDL_low and LDL_high groups. The findmarker utility, coupled with Pearson correlation analysis, facilitated the identification of pivotal genes correlated with LDL indices. An integrative approach to transcriptomic data analysis was adopted, utilizing a machine learning framework to devise an LDL‐associated signature (LAS). This enabled the delineation of genomic disparities, pathway enrichments, immune cell dynamics, and pharmacological sensitivities between LAS stratifications. Results: Enhanced cellular crosstalk was observed in the LDL_high group, with the CoxBoost+Ridge algorithm achieving the apex c‐index for LAS formulation. Benchmarking against 144 extant LUAD models underscored the superior prognostic acuity of LAS. Elevated LAS indices were synonymous with adverse outcomes, diminished immune surveillance, and an upsurge in pathways conducive to neoplastic proliferation. Notably, a pronounced susceptibility to paclitaxel and gemcitabine was discerned within the high‐LAS cohort, delineating prospective therapeutic corridors. Conclusion: This study elucidates the significance of LRGs within the TME and introduces an LAS for prognostication in LUAD patients. Our findings accentuate putative therapeutic targets and elucidate the clinical ramifications of LAS deployment. [ABSTRACT FROM AUTHOR]

OBJECTIVES The goal was to explore clinical factors and build a predictive model for the disease-free and overall survival of patients with non-small cell lung cancer (NSCLC) receiving neoadjuvant chemotherapy combined with immune checkpoint inhibitors. METHODS Inclusion criteria for patients in this multicentre study were as follows: (i) Patients who were diagnosed with stages I–III NSCLC after a bronchoscopy biopsy or puncture; (ii) patients who were examined with computed tomography/positron emission tomography-computed tomography before treatment and surgery; (iii) patients who received neoadjuvant chemotherapy combined with immune checkpoint inhibitors for 2 to 6 cycles preoperatively; (iv) patients whose peripheral blood indicators and tumour markers were assessed before treatment and preoperatively; (v) patients who underwent radical lung cancer surgery after neoadjuvant therapy. Cases were divided into high- and low-risk groups according to 78 clinical indicators based on a 10-fold Least Absolute Shrinkage and Selection Operator selection. We used Cox proportional hazards models to predict disease-free and overall survival. Then, we used time-dependent area under the curve and decision curve analyses to examine the accuracy of the results. RESULTS Data were collected continuously, and 212 and 85 cases were randomly assigned to training and testing sets, respectively. The area under the curve for the prediction of disease-free survival (training: 1 year, 0.83; 2 years, 0.81; 3 years, 0.83 versus testing: 1 year, 0.65; 2 years, 0.66; 3 years, 0.70), overall survival (training: 1 year, 0.86; 2 years, 0.85; 3 years, 0.86 versus testing: 1 year, 0.66; 2 years, 0.57; 3 years, 0.70) were determined. The coefficient factors including pathological response; preoperative tumour maximum diameter; preoperative lymph shorter diameter; preoperative tumour and lymph maximum standardized uptake value; change in tumour standardized uptake value preoperatively; and blood-related risk factors were favourably associated with prognosis (P  < 0.001). CONCLUSIONS Our prediction model, which integrated data from preoperative positron emission tomography-CT, preoperative blood parameters and pathological response, was able to make highly accurate predictions for disease-free and overall survival in patients with NSCLC receiving neoadjuvant immunity with chemical therapy. [ABSTRACT FROM AUTHOR]

In the southeastern US, substantial emissions of isoprene from deciduous trees undergo atmospheric oxidation to form secondary organic aerosol (SOA) that contributes to fine particulate matter (PM2.5). Laboratory studies have revealed that anthropogenic pollutants, such as sulfur dioxide (SO2), oxides of nitrogen (NO x ), and aerosol acidity, can enhance SOA formation from the hydroxyl radical (OH)-initiated oxidation of isoprene; however, the mechanisms by which specific pollutants enhance isoprene SOA in ambient PM2.5 remain unclear. As one aspect of an investigation to examine how anthropogenic pollutants influence isoprene-derived SOA formation, high-volume PM2.5 filter samples were collected at the Birmingham, Alabama (BHM), ground site during the 2013 Southern Oxidant and Aerosol Study (SOAS). Sample extracts were analyzed by gas chromatography-electron ionization-mass spectrometry (GC/EI-MS) with prior trimethylsilylation and ultra performance liquid chromatography coupled to electrospray ionization high-resolution quadrupole time-of-flight mass spectrometry (UPLC/ESI-HR-QTOFMS) to identify known isoprene SOA tracers. Tracers quantified using both surrogate and authentic standards were compared with collocated gas- and particle-phase data as well as meteorological data provided by the Southeastern Aerosol Research and Characterization (SEARCH) network to assess the impact of anthropogenic pollution on isoprene-derived SOA formation. Results of this study reveal that isoprene-derived SOA tracers contribute a substantial mass fraction of organic matter (OM) (~ 7 to ~ 20 %). Isoprene-derived SOA tracers correlated with sulfate ( SO42- ) (r2 = 0.34, n = 117) but not with NO x . Moderate correlations between methacrylic acid epoxide and hydroxymethyl-methyl-α-lactone (together abbreviated MAE/HMML)-derived SOA tracers with nitrate radical production (P[NO3]) (r2 = 0.57, n = 40) were observed during nighttime, suggesting a potential role of the NO3 radical in forming this SOA type. However, the nighttime correlation of these tracers with nitrogen dioxide (NO2) (r2 = 0.26, n = 40) was weaker. Ozone (O3) correlated strongly with MAE/HMML-derived tracers (r2 = 0.72, n = 30) and moderately with 2-methyltetrols (r2 = 0.34, n = 15) during daytime only, suggesting that a fraction of SOA formation could occur from isoprene ozonolysis in urban areas. No correlation was observed between aerosol pH and isoprene-derived SOA. Lack of correlation between aerosol acidity and isoprene-derived SOA is consistent with the observation that acidity is not a limiting factor for isoprene SOA formation at the BHM site as aerosols were acidic enough to promote multiphase chemistry of isoprene-derived epoxides throughout the duration of the study. All in all, these results confirm previous studies suggesting that anthropogenic pollutants enhance isoprene-derived SOA formation.

Adenocarcinoma is the most common type of lung cancer. Epithelial-mesenchymal transition (EMT) is required for tumor invasion/metastasis and the components that control this process are potential therapeutic targets. This study we examined the role of Gli in lung adenocarcinoma and whether its activation regulates metastasis through EMT in lung adenocarcinoma. We found that tumors with high Gli expression had significantly lower E-Cadherin expression in two independent cohorts of patients with lung adenocarcinoma that we studied. In vitro up-regulation of SHh resulted in increased cell migration while small molecule inhibitors of Smo or Gli significantly reduced cell mobility both in a wound healing assay and in a 3D cell invasion assay. Inhibition of Gli in vivo decreased tumor growth and induced an increase in E-Cadherin expression. Our results indicate that Gli may be critical for lung adenocarcinoma metastasis and that a novel Gli inhibitor shows promise as a therapeutic agent by preventing cell migration and invasion in vitro and significantly reducing tumor growth and increasing E-Cadherin expression in vivo.

Secondary organic aerosol (SOA) formation from 2-methyl-3-buten-2-ol (MBO) photooxidation has recently been observed in both field and laboratory studies. Similar to the level of isoprene, the level of MBO-derived SOA increases with elevated aerosol acidity in the absence of nitric oxide; therefore, an epoxide intermediate, (3,3-dimethyloxiran-2-yl)methanol (MBO epoxide), was synthesized and tentatively proposed to explain this enhancement. In this study, the potential of the synthetic MBO epoxide to form SOA via reactive uptake was systematically examined. SOA was observed only in the presence of acidic aerosol. Major SOA constituents, 2,3-dihydroxyisopentanol and MBO-derived organosulfate isomers, were chemically characterized in both laboratory-generated SOA and in ambient fine aerosol collected from the BEACHON-RoMBAS field campaign during the summer of 2011, where MBO emissions are substantial. Our results support the idea that epoxides are potential products of MBO photooxidation leading to the formation of atmospheric SOA and suggest that reactive uptake of epoxides may explain acid enhancement of SOA observed from other biogenic hydrocarbons.

The progression of lung adenocarcinoma (LUAD) from atypical adenomatous hyperplasia (AAH) to invasive adenocarcinoma (IAC) involves a complex evolution of tumour cell clusters, the mechanisms of which remain largely unknown. By integrating single‐cell datasets and using inferCNV, we identified and analysed tumour cell clusters to explore their heterogeneity and changes in abundance throughout LUAD progression. We applied gene set variation analysis (GSVA), pseudotime analysis, scMetabolism, and Cytotrace scores to study biological functions, metabolic profiles and stemness traits. A predictive model for prognosis, based on key cluster marker genes, was developed using CoxBoost and plsRcox (CPM), and validated across multiple cohorts for its prognostic prediction capabilities, tumour microenvironment characterization, mutation landscape and immunotherapy response. We identified nine distinct tumour cell clusters, with Cluster 6 indicating an early developmental stage, high stemness and proliferative potential. The abundance of Clusters 0 and 6 increased from AAH to IAC, correlating with prognosis. The CPM model effectively distinguished prognosis in immunotherapy cohorts and predicted genomic alterations, chemotherapy drug sensitivity, and immunotherapy responsiveness. Key gene S100A16 in the CPM model was validated as an oncogene, enhancing LUAD cell proliferation, invasion and migration. The CPM model emerges as a novel biomarker for predicting prognosis and immunotherapy response in LUAD patients, with S100A16 identified as a potential therapeutic target. [ABSTRACT FROM AUTHOR]

Introduction Epithelial cells receive growth and survival stimuli through attachment to the extracellular matrix (ECM) (1). The loss of attachment to ECM triggers apoptosis, commonly referred to as anoikis (2, [...], The switch from anchorage-dependent to anchorage-independent growth is essential for epithelial metastasis. The underlying mechanism, however, is not fully understood. In this study, we identified growth factor independent-1 (GFI1), a transcription factor that drives the transition from adherent endothelial cells to suspended hematopoietic cells during hematopoiesis, as a critical regulator of anchorage independence in lung cancer cells. GFI1 elevated the numbers of circulating and lung-infiltrating tumor cells in xenograft models and predicted poor prognosis of patients with lung cancer. Mechanistically, GFI1 inhibited the expression of multiple adhesion molecules and facilitated substrate detachment. Concomitantly, GFI1 reconfigured the chromatin structure of the RASGRP2 gene and increased its expression, causing Rap1 activation and subsequent sustained ERK activation upon detachment, and this led to ERK signaling dependency in tumor cells. Our studies unveiled a mechanism by which carcinoma cells hijacked a hematopoietic factor to gain anchorage independence and suggested that the intervention of ERK signaling may suppress metastasis and improve the therapeutic outcome of patients with GFI1-positive lung cancer.