The value of BAL fluid LDH level in differentiating benign from malignant solitary pulmonary nodules

Rapid Generation of Circulating and Mucosal Decoy Human ACE2 using mRNA Nanotherapeutics for the Potential Treatment of SARS-CoV-2

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause lethal pulmonary damage in humans. It contains spike proteins on its envelope that bind to human angiotensin-converting enzyme 2 (hACE2) expressed on airway cells, enabling entry of the virus, and causing infection. The soluble form of hACE2 binds SARS-CoV-2 spike protein, prevents viral entry into target cells, and ameliorates lung injury; however, its short half-life limits therapeutic utilities. Here, synthetic mRNA is engineered to encode a soluble form of hACE2 (hsACE2) to prevent viral infection. A novel lipid nanoparticle (LNP) is used for packaging and delivering mRNA to cells to produce hsACE2 proteins. Intravenously administered LNP delivers mRNA to hepatocytes, leading to the production of circulatory hsACE2 initiated within 2 h and sustained over several days. Inhaled LNP results in lung transfection and secretion of mucosal hsACE2 to lung epithelia, the primary site of entry and pathogenesis for SARS-CoV-2. Furthermore, mRNA-generated hsACE2 binds to the receptor-binding domain of the viral spike protein. Finally, hsACE2 effectively inhibits SARS-CoV-2 and its pseudoviruses from infecting host cells. The proof of principle study shows that mRNA-based nanotherapeutics can be potentially deployed to neutralize SARS-CoV-2 and open new treatment opportunities for coronavirus disease 2019 (COVID-19).

Atractylenolide III attenuates bleomycin-induced experimental pulmonary fibrosis and oxidative stress in rat model via Nrf2/NQO1/HO-1 pathway activation

BACKGROUND

Bleomycin (BLM) is a chemotherapy drug used to treat cancer, one of which side effects is that it can lead to pulmonary fibrosis (PF). Atractylenoide III (AtrIII), derived from the dried roots of rhizoma atractylodis of compositae, is one of the main active substances of rhizoma atractylodis. It has anti-inflammatory, anti-tumor and other effects. This study aimed to investigate whether AtrIII alleviated BLM-induced PF and oxidative stress in rats through the nuclear factor erythroid-2-related factor 2/NQO1,NAD(P)H:quinine oxidoreductase 1/Heme oxygenase-1 (Nrf2/NQO1/HO-1) pathway.

METHODS

A BLM-induced pulmonary fibrosis model in SD rats was established. The respiratory dynamics were evaluated by using Wholebody flow-through plethysmography. Lung injury and pulmonary fibrosis were observed by Hematoxylin-eosin (HE) and Masson staining. Apoptosis was assay by Tunel assay. Inflammatory factors were detected with commercial kits. Expression of mRNAs and proteins were detected by RT-qPCR and Western blot, respectively.

RESULTS

AtrIII (1.2, 2.4 mg/kg) improved the lung injury and lung function in the BLM-induced Sprague-Dawley (SD) rats. AtrIII reduced the apoptosis rate and protein expression of Caspase-3 and Caspase-9. AtrIII (1.2, 2.4 mg/kg) decrease the pulmonary fibrosis damage and protein expression transforming growth factor-β (TGF-β) and α-smooth muscle actin (α-SMA). AtrIII also down-regulated the levels of interleukin 6 (IL-6), inductible nitric oxide synthase (iNOS) and tumor necrosis factor-α (TNF-α), while up-regulated the level of IL-10 in peripheral blood serum. Moreover, AtrIII (1.2, 2.4 mg/kg) increased the activity of superoxide dismutase (SOD) and glutathione (GSH), while decreased the malondialdehyde (MDA) content and lactate dehydrogenase (LDH) activity. AtrIII (1.2, 2.4 mg/kg) increased the levels of Nrf2, NQO1 and HO-1. In addition, AtrIII reversed the effects of Nrf2 interference on pulmonary fibrosis damage, decreased SOD and GSH activity, and increased MDA content.

CONCLUSION

AtrIII could attenuate the pulmonary fibrosis and reliev oxidative stress through the Nrf2/NQO1/ HO-1 pathway.

Elevated uric acid and adenosine triphosphate concentrations in bronchoalveolar lavage fluid of eosinophilic pneumonia

BACKGROUND

Recent evidence has suggested that the innate immune response may play a role in the development of eosinophilic airway inflammation. We previously reported that uric acid (UA) and adenosine triphosphate (ATP), two important damage-associated molecular pattern molecules (DAMPs), activate eosinophil functions, suggesting that these molecules may be involved in the development of eosinophilic airway inflammation. The objective of this study was to measure the concentrations of DAMPs including UA and ATP in the bronchoalveolar lavage fluid (BALF) of patients with eosinophilic pneumonia (EP).

METHODS

BAL was performed in patients with EP including acute and chronic eosinophilic pneumonia, and in patients with hypersensitivity pneumonia, and sarcoidosis. UA, ATP, and cytokine concentrations in the BALF were then measured.

RESULTS

The UA concentration was increased in the BALF of EP patients. UA concentrations correlated with eosinophil numbers, and with eosinophil-derived neurotoxin and interleukin (IL)-5 concentrations. Furthermore, the ATP concentration was increased in the BALF of EP patients and ATP concentrations correlated with UA concentrations. Moreover, IL-33 was increased in EP patients and IL-33 concentrations correlated with UA and ATP concentrations.

CONCLUSIONS

The UA and ATP concentration was increased in the BALF of EP patients. UA concentrations correlated with eosinophil numbers, and with ATP and IL-33 concentrations. Our findings suggest that DAMPs such as UA and ATP play a role in the pathogenesis of EP.

Elevated expression of MMP-2 and TIMP-2 cooperatively correlates with risk of lung cancer

Lung cancer is one of the most common form of malignant diseases and the leading cause of cancer-related mortality worldwide. It is reported that approximately two-thirds of lung cancer patients is the presence of advance disease at the time of diagnosis. Hence novel lung cancer diagnostic tests, which can be used to screen individuals at high risk, are required. In the derivation cohort, a total of 88 patients admitted into hospital with suspected lung cancer were included. Bronchial alveolar lavage fluid (BALF) and lung tissue samples were collected from included patients, and were analyzed for MMP-2 and TIMP-2 expression. The results showed a higher level of MMP-2 and TIMP-2 expression and secretion in airways of lung cancer patients than that of benign diseases. A statistically significant correlation was observed between MMP-2 and TIMP-2. In addition, a validation cohort involving 107 patients was conducted to confirm these results. Interesting, BALF MMP-2 and TIMP-2 showed a high sensitivity and specificity in predicting the malignant nature of pulmonary disease in both derivation cohort and validation cohort. The findings in this study suggested that elevated expression of MMP-2 and TIMP-2 cooperatively correlates with risk of lung cancer. Measurement of MMP-2 and TIMP-2 in BALF might be helpful for differential diagnosis of primary lung cancer.

Diagnostic value of epidermal growth factor, cancer antigen 125, and cancer antigen 15-3 in bronchoalveolar lavage fluid of lung cancer

AIM

In the present study, we assessed the diagnostic value of epidermal growth factor (egf) and cancer antigens 125 (ca125) and 15-3 (ca15-3) in bronchoalveolar lavage fluid (balf) of lung cancer from 79 enrolled patients with suspected lung cancer.

METHODS

All patients underwent fibrescopic examination, during which balf samples were collected. Levels of egf, ca125, and ca15-3 were determined in balf using commercially available test kits.

RESULTS

The results showed that levels of egf in balf were significantly higher in patients with lung cancer than in patients with benign diseases (p < 0.01); no significant differences for ca125 (p = 0.67) or ca15-3 (p = 0.43) in balf were observed between the lung cancer patients and the non-cancer control subjects. With a cut-off value of 27.22 pg/mL, egf showed a sensitivity of 63.6% and a specificity of 65.7% in predicting the malignant nature of pulmonary disease.

CONCLUSIONS

The study findings suggest that levels of egf are significantly increased in balf from patients with lung cancer than in balf from patients with benign disease. Detection of the level of egf in balf is proposed as a noninvasive test to identify patients at high risk for lung cancer.

Smoking-promoted oxidative DNA damage response is highly correlated to lung carcinogenesis

Oxidative stress induced by tobacco smoking is one of the main causes of DNA damage and is known to be involved in various cancers. Smoking is the leading cause of lung cancer, while the role of cigarette smoke-induced oxidative DNA damage response during lung carcinogenesis is largely unknown. In this study, we investigated oxidative DNA damage response levels in smoking and nonsmoking patients with lung cancer, and evaluated the potential diagnostic value of 8-OHdG for lung cancer. We observed a higher level of 8-OHdG expression and secretion in airways of lung cancer patients than that of noncancer controls. 8-OHdG expression was associated with the TNM stages. Additionally, cigarette smoke-induced oxidative DNA damage response was observed in bronchial epithelial cells in vitro and in vivo. A statistical significance correlation was found between the levels of 8-OHdG and smoking index. With a cut-off value of 2.86 ng/ml, 8-OHdG showed a sensitivity and specificity of 70.0% and 73.7%, respectively, to identify a patient with lung cancer. These findings not only underscore the importance of smoking in oxidative DNA damage response of lung cancer patients, but also suggest 8-OHdG as a potential diagnostic biomarker for lung cancer.

TGF-β1, IL-6, and TNF-α in bronchoalveolar lavage fluid: useful markers for lung cancer?

Changes of cytokines in bronchoalveolar lavage fluid (BALF) reflect immunologic reactions of the lung in pulmonary malignancies. Detection of biomarkers in BALF might serve as an important method for differential diagnosis of lung cancer. A total of 78 patients admitted into hospital with suspected lung cancer were included in our study. BALF samples were obtained from all patients, and were analyzed for TGF-β1, IL-6, and TNF-α using commercially available sandwich ELISA kits. The levels of TGF-β1 in BALF were significantly higher in patients with lung cancer compared with patients with benign diseases (P = 0.003). However, no significant difference of IL-6 (P = 0.61) or TNF-α (P = 0.72) in BALF was observed between malignant and nonmalignant groups. With a cut-off value of 10.85 pg/ml, TGF-β1 showed a sensitivity of 62.2%, and a specificity of 60.6%, in predicting the malignant nature of pulmonary disease. Our data suggest that TGF-β1 in BALF might be a valuable biomarker for lung cancer. However, measurement of IL-6 or TNF-α in BALF has poor diagnostic value in lung cancer.

Evaluation of VEGF-C and tumor markers in bronchoalveolar lavage fluid for lung cancer diagnosis

A total of 87 patients were enrolled and bronchoalveolar lavage fluid (BALF) samples were obtained from all subjects. A significant difference was found in BALF VEGF-C level between patients with squamous cell carcinoma and benign diseases (P = 0.043). In addition, the concentration of NSE in BALF form the malignant group was significantly higher compared with that of the benign groups (P = 0.018). However, no statistical difference was observed in BALF CEA (P = 0.375) or CYFRA21-1 (P = 0.838) between lung cancer patients and nonmalignant controls. With a cut-off value of 2.06 ng/ml, NSE had a sensitivity of 72.9%, a specificity of 69.2%, respectively, in predicting the malignant nature of pulmonary mass. Our study observed that the level of VEGF-C was increased in BALF of patients with squamous cell carcinoma. Moreover, we found that NSE was significantly higher in BALF of lung cancer patients than in benign diseases.

Utility of VEGF and sVEGFR-1 in bronchoalveolar lavage fluid for differential diagnosis of primary lung cancer

Published data have shown that the levels of vascular endothelial growth factor (VEGF) and soluble VEGF receptor-1 (sVEGFR-1) in plasma and pleural effusion might be usefulness for lung cancer diagnosis. Here, we performed a prospective study to investigate the utility of VEGF and sVEGFR-1 in bronchoalveolar lavage fluid (BALF) for differential diagnosis of primary lung cancer. A total of 56 patients with solitary pulmonary massed by chest radiograph or CT screening were enrolled in this study. BALF and plasma samples were obtained from all patients and analyzed for VEGF and sVEGFR-1 using a commercially available sandwich ELISA kit. The results showed that the levels of VEGF in BALF were significantly higher in patients with a malignant pulmonary mass compared with patients with a benign mass (P < 0.001). However, no significant difference of sVEGFR-1 in BALF was found between malignant and non-malignant groups (P = 0.43). With a cut-off value of 214 pg/ml, VEGF showed a sensitivity and specificity of 81.8% and 84.2%, respectively, in predicting the malignant nature of a solitary pulmonary mass. Our study suggests that VEGF is significantly increased in BALF among patients with lung cancer than in benign diseases. Measurement of VEGF in BALF might be helpful for differential diagnosis of primary lung cancer.

Lactic acid is elevated in idiopathic pulmonary fibrosis and induces myofibroblast differentiation via pH-dependent activation of transforming growth factor-β

RATIONALE

Idiopathic pulmonary fibrosis (IPF) is a complex disease for which the pathogenesis is poorly understood. In this study, we identified lactic acid as a metabolite that is elevated in the lung tissue of patients with IPF.

OBJECTIVES

This study examines the effect of lactic acid on myofibroblast differentiation and pulmonary fibrosis.

METHODS

We used metabolomic analysis to examine cellular metabolism in lung tissue from patients with IPF and determined the effects of lactic acid and lactate dehydrogenase-5 (LDH5) overexpression on myofibroblast differentiation and transforming growth factor (TGF)-β activation in vitro.

MEASUREMENTS AND MAIN RESULTS

Lactic acid concentrations from healthy and IPF lung tissue were determined by nuclear magnetic resonance spectroscopy; α-smooth muscle actin, calponin, and LDH5 expression were assessed by Western blot of cell culture lysates. Lactic acid and LDH5 were significantly elevated in IPF lung tissue compared with controls. Physiologic concentrations of lactic acid induced myofibroblast differentiation via activation of TGF-β. TGF-β induced expression of LDH5 via hypoxia-inducible factor 1α (HIF1α). Importantly, overexpression of both HIF1α and LDH5 in human lung fibroblasts induced myofibroblast differentiation and synergized with low-dose TGF-β to induce differentiation. Furthermore, inhibition of both HIF1α and LDH5 inhibited TGF-β-induced myofibroblast differentiation.

CONCLUSIONS

We have identified the metabolite lactic acid as an important mediator of myofibroblast differentiation via a pH-dependent activation of TGF-β. We propose that the metabolic milieu of the lung, and potentially other tissues, is an important driving force behind myofibroblast differentiation and potentially the initiation and progression of fibrotic disorders.

Flexible bronchoscopy and its role in the staging of non-small cell lung cancer

Technologic advances in bronchoscopy continue to improve the ability to perform minimally invasive, accurate evaluations of the tracheobronchial tree and to perform an ever-increasing array of diagnostic, staging, therapeutic, and palliative interventions. The role of both old and new diagnostic bronchoscopy will continue to evolve as further improvements are made in bronchoscopes, accessory equipment, and imaging technologies. The major challenge is the adoption of the many new bronchoscopic techniques into routine clinical practice. There is a need for well-designed studies to delineate the appropriate use of these interventions and to better define their limitations and cost effectiveness.