Immune cells mediated the causal relationship between the gut microbiota and lung cancer: a Mendelian randomization study.

Introduction: The gut microbiota (GM) influences the occurrence and progression of lung cancer (LC), with potential involvement of immune cells (IC). We aimed to investigate the causal impact of GM on LC and identify potential immune cell mediators. Methods: The utilized data for the Genome-Wide Association Studies (GWAS) were summarized as follows: gut microbiota data from the Dutch Microbiome Project (DMP) (N = 7,738), lung cancer data from the Transdisciplinary Research in Cancer of the Lung (TRICL) and International Lung Cancer Consortium (ILCCO) (Ncase = 29,266, Ncontrol = 56,450) included four types of cancer: NSCLC, LUAD, LUSC, and SCLC, and immune cell data from European populations (N = 3,757). We employed bi-directional two-sample univariable Mendelian randomization (UVMR), multivariable Mendelian randomization (MVMR), and mediation analysis to assess the causal relationship between GM and LC and potential immune cell mediators. Results: Bi-directional UVMR analysis revealed that 24 gut microbiota species can affect LC, while LC can affect the abundance of 17 gut microbiota species. Mediation analysis demonstrated that six immune cells mediated the causal relationships of seven gut microbiota species on LC: "CCR7 on naive CD8+ T cell" mediated the causal relationship between s_Alistipes_putredinis and LUAD, with a mediation proportion of 9.5% and P = 0.018; "IgD- CD27- B cell %lymphocyte" mediated the causal relationships between g_Gordonibacter and s_Gordonibacter_pamelaeae with LUSC, with mediation proportions of 11.8% and 11.9%, respectively and P = 0.029; "CD20- CD38- B cell %lymphocyte" mediated the causal relationship between s_Bacteroides_clarus and SCLC, with a mediation proportion of 13.8% and P = 0.005; "CD20 on IgD+ CD38- unswitched memory B cell" mediated the causal relationship between s_Streptococcus_thermophilus and SCLC, with a mediation proportion of 14.1% and P = 0.023; "HLA DR on CD14- CD16+ monocyte" mediated the causal relationship between s_Bifidobacterium_bifidum and SCLC, with a mediation proportion of 8.7% and P = 0.012; "CD45 on Granulocytic Myeloid-Derived Suppressor Cells" mediated the causal relationship between f_Lactobacillaceae and SCLC, with a mediation proportion of 4.0% and P = 0.021. Conclusion: This Mendelian randomization study identified several specific gut microbiotas that exhibit causal relationships with lung cancer and potentially mediate immune cells.

Anti-angiogenic therapy for advanced primary pulmonary lymphoepithelioma-like carcinoma: a retrospective multicenter study.

PURPOSE: Primary pulmonary lympho-epithelioma-like carcinoma (PPLELC) is a rare subtype of primary non-small cell lung cancer (NSCLC). Currently, there is still lack of research data on anti-angiogenic therapy of advanced PPLELC. The purpose of this study was to investigate the efficacy and safety of anti-angiogenic therapy combined with chemotherapy compared with traditional chemotherapy for these patients. METHODS: Advanced PPLELC patients admitted to six grade A hospitals from January 2013 to January 2021 were selected. The patients received anti-angiogenic therapy combined with chemotherapy (AT group) or chemotherapy (CT group) alone. RESULTS: A total of 65 patients were included in this study, including 31 patients in the AT group treated with anti-angiogenic therapy combined with chemotherapy and 34 patients in the CT group treated with chemotherapy alone. As of October 1, 2021, the median progression-free survival (PFS) in the AT group was 11.2 months [95% confidence interval (CI), 5.9-16.5]. The median PFS in the CT group was 7.0 months [95%CI, 5.1-8.9] [Hazard Ratio (HR), 0.49; 95%CI, 0.29-0.83; P = 0.008]. The 1-year PFS rates were 41.9% and 17.6%, respectively. The overall response rates (ORR) of two groups were 45.2% (95% CI, 0.27-0.64), 38.2% (95% CI, 0.21-0.56), (P = 0.571). The disease control rates (DCR) of two groups were 93.5% (95% CI, 0.84-1.03), 88.2% (95% CI, 0.77-1.00), (P = 0.756). CONCLUSION: Among patients with advanced PPLELC, the PFS of patients with anti-angiogenic therapy combined with chemotherapy is better than that of patients with chemotherapy alone. Anti-angiogenic therapy combined with chemotherapy is an optional treatment scheme.

Alterations of lung microbiota in patients with non-small cell lung cancer.

The role of lung microbiota in non-small cell lung cancer remains unclear. We investigated the characteristics and functional roles of lung microbiota in non-small cell lung cancer. Bronchoalveolar lavage fluid samples were obtained from patients with non-small cell lung cancer (n = 46) and with benign lung disease (n = 29). The differences in composition and gene expression in the microbiota between the samples were analyzed using 16s rRNA sequencing. The oncogenic genus (Veillonella) was then evaluated in the progression of lung cancer in C57 BL/6 mice. Compared to benign lung disease, the lung microbiota in non-small cell lung cancer was significantly altered, both in terms of α- and ß-diversity. In terms of bacterial composition, the non-small cell lung cancer group was enriched with two Phyla (Firmicutes, Bacteroidetes) and three genera (Streptococcus, Prevotella, Veillonella). Prevotella and Veillonella were most strongly associated with non-small cell lung cancer, and Veillonella significantly promoted the progression of lung cancer in vivo. Moreover, metabolic prediction revealed that ribosomes, biosynthesis of secondary metabolites, and pyrimidine metabolism were among the enriched pathways that may be involved in the progression of non-small cell lung cancer. Overall, results suggest that the progression of non-small cell lung cancer is followed by significant changes in the composition and function of the lung microbiota. These differing genera may be potential diagnostic markers and therapeutic targets.

Immunosuppression and cardiovascular dysfunction in patients with severe versus mild coronavirus disease 2019: a case series.

OBJECTIVES: As coronavirus disease 2019 (COVID-19) continues to spread globally, we aimed to describe and compare changes in the immune and cardiovascular systems of patients with mild versus severe COVID-19 at different time points during the course of disease. METHODS: One hundred and one patients diagnosed with COVID-19 who underwent serial peripheral blood collection and chest computed tomography (CT) imaging were enrolled in this study and grouped by the severity of their illness. Changes in the immune and cardiovascular systems were analysed and compared between groups. RESULTS: The study included 43 women and 58 men, with a median age of 45 years (interquartile range [IQR], 16-71). We identified spleen shrinkage in 27.7% of study patients. Ratios of spleen volume to patient (skin) volume were compared, with evidence that severe patients had more splenic shrinkage than mild patients. Lymphopenia was observed in 65.3% of patients, and 27.3% of patients had persistently low levels of lymphocytes after discharge. Tachycardia occurred mainly during the first 2 days of hospitalisation, with increases in creatine kinase-myocardial band levels in 10 (9.9%) patients and arrhythmias in 16 (15.8%) patients. CONCLUSIONS: In addition to pulmonary manifestations, our study demonstrated that other organ systems can also be affected during COVID-19 infection, with evidence of immunosuppression and cardiovascular dysfunction, which may contribute to increased mortality rates in critically ill COVID-19 patients.

MicroRNA-365 promotes lung carcinogenesis by downregulating the USP33/SLIT2/ROBO1 signalling pathway.

BACKGROUND: Abnormal microRNA expression is closely related to cancer occurrence and development. miR-365a-3p plays an oncogenic role in skin cancer, but its role in lung cancer remains unclear. In this study, we aimed to investigate its role and underlying molecular mechanisms in lung cancer. METHODS: Western blot and real-time quantitative PCR (qPCR) were used to detect the expression of miR-365a-3p in lung adenocarcinoma and lung cancer cell lines. The effects of miR-365a-3p on lung cancer cell proliferation, migration, and invasion were also explored in vitro. The potential miR-365a-3p that targets USP33 was determined by dual luciferase reporter assay and verified by qPCR and western blot analysis. miR-365a-3p acts as an oncogene by promoting lung carcinogenesis via the downregulation of the miR-365a/USP33/SLIT2/ROBO1 axis based on western blot analysis. Subcutaneous tumourigenesis further demonstrated that miR-365a-3p promotes tumour formation in vivo. RESULTS: miR-365a-3p was upregulated in lung adenocarcinoma and lung cancer cell lines. Overexpression of miR-365a-3p promoted and inhibition of miR-365a-3p suppressed the proliferation, migration, and invasion of lung cancer cells. We identified USP33 as the downstream target of miR-365a-3p and observed a negative correlation between miR-365a-3p and USP33 expression in lung adenocarcinoma patients. The miR-365/USP33/SLIT2/ROBO1 axis, a new mechanism, was reported to inhibit the invasion and metastasis of lung cancer. A nude mouse model of lung cancer further verified these findings. CONCLUSIONS: In summary, miR-365a-3p acts as an oncogene by promoting lung carcinogenesis via the downregulation of the USP33/SLIT2/ROBO1 signalling pathway, making the miR-365/USP33/SLIT2/ROBO1 axis a new mechanism of lung cancer promotion and a novel therapeutic target for predicting prognosis and response to gene therapy.

[Regulatory role of Shh signaling pathway in lung development in fetal mice].

OBJECTIVE: To investigate the regulatory role of classical Shh signaling pathway in the development of the epithelium and mesenchyme (bronchial cartilage and smooth muscles) during lung development in fetal mice. METHODS: Immunohistochemical technique was used to detect the expression of Shh signaling pathway receptor Smo and Pdgfr-α in murine fetal lungs to explore the spatial and temporal characteristics of their expression. Based on the interstitial specificity of Pdgfr-α expression, we constructed a Pdgfr-α-cre to establish a E12.5 - E16.5 transgenic mice with specific knockout of the key Shh signaling molecule Smo in the pulmonary interstitium with tamoxifen induction. Immunofluorescence technique was used to observe the epithelium and mesenchyme (bronchial cartilage and smooth muscle) during fetal lung development in the transgenic mice to assess the role of Shh signaling pathway in the epithelial-to-mesenchymal (EMT) transition during the lung development. RESULTS: Smo was highly expressed in the epithelial and stromal lung tissues in the pseudoglandular stage and was gradually lowered over time with its distribution mainly in the interstitial tissues. Pdgfr-α was enriched in the distal lung epithelial and mesenchy tissues in early embryonic lungs and gradually migrated to the proximal stroma until becoming concentrated around the main bronchial proximal stroma. We successfully specific established mouse models of specific mesenchymal Smo knockout. Compared with the control group, the transgenic mice during E12.5-E16.5 showed significantly reduced lung the volume and bronchial branching with also decreased expression of the proximal epithelial P63 (P<0.05). The transgenic mice exhibited alterations in the expression of α-smooth muscle actin with delayed bronchial cartilage development and decreased expression of mucoprotein. CONCLUSION: The temporospatial specific expression of Shh signaling pathway plays an important role in developmental regulation of mouse embryonic lung epithelium and mesenchyme (bronchial cartilage and smooth muscle).