Systemic Profiles of microRNAs, Redox Balance, and Inflammation in Lung Cancer Patients: Influence of COPD

NF-κB-mediated EAAT3 upregulation in antioxidant defense and ferroptosis sensitivity in lung cancer

Cellular glutathione (GSH) in lung cancer cells represents the most abundant antioxidant. GSH production is regulated not only by upregulated cystine/glutamate exchanger (xCT) but also by the involvement of glutamate transporters, specifically excitatory amino acid transporter 3 (EAAT3). Our prior research established that the uptake of glutamate via EAAT3 plays a pivotal role in driving cystine uptake through xCT, contributing to GSH biosynthesis during lung tumorigenesis. Nevertheless, the underlying mechanism governing the upregulation of EAAT3 remains enigmatic. In this study, we conducted a comprehensive reanalysis of publicly available data and employed the Gprc5a-/-/SR-IκB mouse model alongside in vitro cell experiments to elucidate the correlations between NF-κB and EAAT3 in lung cancer. We observed that EAAT3 knockdown, similar to NF-κB inhibition, led to the accumulation of reactive oxygen species (ROS) and increased sensitivity to ferroptosis induction by RAS-selective lethal 3 (RSL3). Mechanistic insights were obtained through chromatin immunoprecipitation and luciferase reporter assays, revealing that NF-κB induces EAAT3 expression via two putative cis-elements within its promoter. Furthermore, our investigation unveiled the upregulation of EAAT3 in a subset of clinical non-small cell lung cancer (NSCLC) tissues, exhibiting a positive correlation with the P65 protein. In addition, the inflammatory factor of smoking was found to augment EAAT3 expression in both human and murine experimental models. These findings collectively emphasize the pivotal role of the NF-κB/EAAT3 axis in managing antioxidant stress and influencing lung cancer development. Moreover, this research offers insights into the potential for a combined ferroptosis therapy strategy in lung cancer treatment.

Aucubin Alleviates Chronic Obstructive Pulmonary Disease by Activating Nrf2/HO-1 Signaling Pathway

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a common chronic respiratory disease with high death rates. Aucubin is an iridoid glycoside extracted from Eucommia ulmoides with antioxidative and anti-inflammatory properties in human diseases. This study aimed to investigate its specific function in mouse and cell models of COPD.

METHODS

The COPD mouse model was established by exposing mice to a long-term cigarette smoke (CS). The number of inflammatory cells and the contents of inflammatory factors tumor necrosis factor alpha (TNF-α), interleukin 6 (IL-6), and IL-8 in bronchoalveolar lavage fluid (BALF) of CS-exposed mice were measured. The levels of superoxide dismutase (SOD), glutathione (GSH), malondialdehyde (MDA), and myeloperoxidase (MPO) in the lung tissues were estimated. Masson staining and hematoxylin-eosin (H&E) staining were utilized to evaluate pulmonary fibrosis and emphysema in CS-treated mice. Cell apoptosis in the lung tissues was estimated by terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL) assay. Western blot was applied to quantify protein levels of nuclear factor erythroid 2-related factor 2 (Nrf2), heme oxygenase-1 (HO-1), and apoptotic markers. COPD cell model was established by exposing mouse lung epithelial cells (MLE12) with cigarette smoke extract to further verify the properties of aucubin in vitro.

RESULTS

Aucubin reduced the number of inflammatory cells and decreased the contents of TNF-α, IL-6, and IL-8 in BALF of CS-treated mice. The oxidative stress, lung emphysema, fibrosis, and lung cell apoptosis induced by CS exposure were ameliorated by aucubin administration. Aucubin activated the Nrf2/HO-1 signaling pathway in vitro and in vivo. Pretreatment with ML385, a specific Nrf2 inhibitor, antagonized the protective effects of aucubin on inflammation, oxidative stress, fibrosis, and cell apoptosis in COPD.

CONCLUSION

Aucubin alleviates inflammation, oxidative stress, apoptosis, and pulmonary fibrosis in COPD mice and CSE-treated MLE12 cells by activating the Nrf2/HO-1 signaling pathway.

International expert consensus on diagnosis and treatment of lung cancer complicated by chronic obstructive pulmonary disease

BACKGROUND

Lung cancer combined by chronic obstructive pulmonary disease (LC-COPD) is a common comorbidity and their interaction with each other poses significant clinical challenges. However, there is a lack of well-established consensus on the diagnosis and treatment of LC-COPD.

METHODS

A panel of experts, comprising specialists in oncology, respiratory medicine, radiology, interventional medicine, and thoracic surgery, was convened. The panel was presented with a comprehensive review of the current evidence pertaining to LC-COPD. After thorough discussions, the panel reached a consensus on 17 recommendations with over 70% agreement in voting to enhance the management of LC-COPD and optimize the care of these patients.

RESULTS

The 17 statements focused on pathogenic mechanisms (n=2), general strategies (n=4), and clinical application in COPD (n=2) and lung cancer (n=9) were developed and modified. These statements provide guidance on early screening and treatment selection of LC-COPD, the interplay of lung cancer and COPD on treatment, and considerations during treatment. This consensus also emphasizes patient-centered and personalized treatment in the management of LC-COPD.

CONCLUSIONS

The consensus highlights the need for concurrent treatment for both lung cancer and COPD in LC-COPD patients, while being mindful of the mutual influence of the two conditions on treatment and monitoring for adverse reactions.

Respiratory and Peripheral Muscle Weakness and Body Composition Abnormalities in Non-Cystic Fibrosis Bronchiectasis Patients: Gender Differences

As demonstrated in COPD, bronchiectasis patients may experience respiratory and peripheral muscle dysfunction. We hypothesized that respiratory and peripheral (upper and lower limbs) muscle function and nutritional status may be more significantly altered in female than in males for identical age and disease severity. In mild-to-moderate bronchiectasis patients (n = 150, 114 females) and 37 controls (n = 37, 21 females), radiological extension, maximal inspiratory and expiratory pressures (MIP and MEP), sniff nasal inspiratory pressure (SNIP), hand grip and quadriceps muscle strengths, body composition, and blood analytical biomarkers were explored. Compared to the controls, in all bronchiectasis patients (males and females), BMI, fat-free mass index (FFMI), fat tissue, upper and lower limb muscle strength, and respiratory muscle strength significantly declined, and FFMI, fat tissue, and quadriceps muscle function were significantly lower in female than male patients. In patients with mild-to-moderate bronchiectasis, respiratory and peripheral muscle function is significantly impaired and only partly related to lung disease status. Quadriceps muscle strength was particularly weakened in the female patients and was negatively associated with their exercise tolerance. Muscle weakness should be therapeutically targeted in bronchiectasis patients. Body composition and peripheral muscle function determination should be part of the comprehensive clinical assessment of these patients.