Change of Serum Inflammatory Cytokines Levels in Patients With Chronic Obstructive Pulmonary Disease, Pneumonia and Lung Cancer

Euphorbia helioscopia L. inhibits lung tumorigenesis through alleviating exhausted T cell induced by chronic inflammation

ETHNOPHARMACOLOGICAL RELEVANCE

Euphorbia helioscopia L. (ZQ) is a very effective traditional Chinese medicine for treating pneumonia and lung cancer. However, the effects and mechanisms by which ZQ prevents lung tumorigenesis in the presence of chronic inflammation remain unexplored.

AIM

To examine the effects and mechanisms of ZQ in alleviating chronic inflammation-induced T cell exhaustion and inhibiting lung tumorigenesis.

METHODS

A mice model of lung tumorigenesis under chronic inflammation conditions was established by repeated administration of lipopolysaccharide (LPS) and exposure to the tobacco carcinogen nitrosamine 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). Mice were treated with ZQ (0.9, 1.8, and 3.6 g/kg/day) for 25 weeks. Lung pathology and tumor incidence were assessed, and inflammatory cytokine levels in bronchoalveolar lavage fluid (BALF) and serum were measured. Additionally, the proportions of CD3+ T, CD4+ T, and CD8+ T cells and their inhibitory receptors expression were evaluated. In vitro, T cell exhaustion models were induced using inflammatory-conditioned media, followed by treatment with ZQ (0.5, 2, 8 μg/mL). T cell exhaustion markers and characteristics were analyzed, and molecular mechanisms were explored using RNA sequencing and Immunoblotting analysis.

RESULTS

In vivo, ZQ significantly reduced inflammatory infiltration and lung damage, tumor incidence, number, size, and lung and spleen indices in mice. It also markedly lowered the levels of pro-inflammatory cytokines and immunosuppressive cytokines in BALF and serum. Additionally, ZQ improved the proportions of CD3+ T, CD4+ T, and CD8+ T cells and significantly decreased the expression of inhibitory receptors on CD4+ T and CD8+ T cells in the lung tissues and spleen. In vitro, ZQ effectively alleviated T cell exhaustion induced by the inflammatory environment, marked by reduced expression of inhibitory receptors, increased cytokine secretion, improved proliferation, and enhanced tumoricidal activity. RNA sequencing revealed that ZQ significantly downregulated the JAK-STAT signaling and upregulated stemness-associated pathways. Immunoblotting results indicated that treatment with ZQ markedly reduced the phosphorylation of Signal transducer and activator of transcription 3 (STAT3) and increased the expression of T cell factor -1/7 (TCF1/7).

CONCLUSION

ZQ inhibits lung tumorigenesis in LPS/NNK-treated mice through alleviating exhausted T cells induced by chronic inflammation, which is attributed to the suppression of STAT3 activation and the maintenance of stemness characteristics in T cells. These findings provide experimental evidence for the potential use of ZQ in preventing and treating lung tumourigenesis in patients with chronic inflammation and the clinical management of lung cancer patients with concomitant chronic inflammation.

The gut microbiota-SCFA-inflammation axis in patients with AECOPD

OBJECTIVES

The aim of the study was to explore the alteration of microbiota and SCFA in gut and inflammation in acute exacerbation chronic obstructive pulmonary disease (AECOPD) patients, and to test the hypothesis that a disorder of gut microbiota will lead to the alteration of SCFA, which will aggravate inflammation in AECOPD patients.

METHODS AND RESULTS

24 patients with AECOPD and 18 healthy volunteers were included in the study. Gut microbiota were analyzed by 16S rDNA and serum was used to detect levels of inflammatory factors by ELISA. Fatty acid concentrations were determined in lumen via gas chromatography-mass spectrometry. The richness and diversity of gut microbiota were decreased in AECOPD patients. β-diversity analysis revealed differences between AECOPD patients and healthy controls. p_Bacteroidetes, g_Paraprevotella, g_Ruminococcus2, g_Parasutterella, o_Rhodospirillales, and g_Romboutsia in the healthy controls and p_Firmicutes, o_Actinomycetales, f_Actinomycetadeae, g_Actinomyces, g_Mogibacterium, f_Veillonellaceae, f_Enterococcaceae, and g_Enterococcus in AECOPD patients were the most abundant microbiota. SCFA levels were decreased in patients with AECOPD. In addition, the results demonstrated that except for a reduction in IL-6, there was no change in inflammatory markers in AECOPD patients.

CONCLUSION

In AECOPD patients, the gut microbiota-SCFA-inflammation axis is augmented, with decreased diversity and abundance of gut microbiota, leading to a reduction in SCFA and an imbalance of inflammation.

Analysis of Predictive Value of Cellular Inflammatory Factors and T Cell Subsets for Disease Recurrence and Prognosis in Patients with Acute Exacerbations of COPD

Objective

To explore the predictive value of cellular inflammatory factors and T cell subsets for disease recurrence and prognosis in patients with acute exacerbations of chronic obstructive pulmonary disease (COPD).

Methods

Serum samples were collected from the two groups to detect and compare the levels of inflammatory cytokines [interleukin-1β (IL-1β), interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α)], T cell subsets (CD4+, CD8+), and clinical related indicators. Pearson correlation analysis was used to analyze the correlation between inflammatory cytokines, T cell subsets, and clinical indicators. Receiver operating characteristic (ROC) curves were plotted to analyze the predictive value of serum inflammatory factors and T cell subsets for acute exacerbations of COPD.

Results

The observation group had higher levels of IL-1β, IL-6, TNF-α, and CD8+, and lower CD4+ levels (P<0.05). The ratio of forced expiratory volume in 1 second to forced vital capacity (FEV1/FVC) was lower, while procalcitonin (PCT) and white blood cell count (WBC) were higher (P<0.05). Correlation analysis showed positive correlations between IL-1β, IL-6, TNF-α, and CD8+, and negative correlations with CD4+ and FEV1/FVC (P<0.05). After 6 months, 15 out of 73 patients had acute recurrences, with higher IL-1β, IL-6, TNF-α, and CD8+ levels (P<0.05). Binary logistic regression identified IL-1β, IL-6, TNF-α, and CD8+ as significant predictors of exacerbations, while CD4+ was protective. ROC analysis showed that combined biomarkers had the highest predictive efficiency (AUC = 0.907).

Conclusion

This study is the first to integrate multiple serum inflammatory factors and T cell subsets into a comprehensive predictive model for acute recurrence of COPD within six months (AUC = 0.907), offering a more accurate prediction than traditional methods. The findings underscore the value of these biomarkers in clinical follow-up and highlight their independent predictive power, providing new insights into the interaction between immune markers and clinical indicators in COPD exacerbations.

Therapeutic potential of 18-β-glycyrrhetinic acid-loaded poly (lactic-co-glycolic acid) nanoparticles on cigarette smoke-induced in-vitro model of COPD

Chronic obstructive pulmonary disease (COPD) is strongly linked to cigarette smoke, which contains toxins that induce oxidative stress and airway inflammation, ultimately leading to premature airway epithelial cell senescence and exacerbating COPD progression. Current treatments for COPD are symptomatic and hampered by limited efficacy and severe side effects. This highlights the need to search for an optimal therapeutic candidate to address the root causes of these conditions. This study investigates the possible potential of poly (lactic-co-glycolic acid) (PLGA)-based nanoparticles encapsulating the plant-based bioactive compound 18-β-glycyrrhetinic acid (18βGA) as a strategy to intervene in cigarette smoke extract (CSE)-induced oxidative stress, inflammation, and senescence, in vitro. We prepared 18βGA-PLGA nanoparticles, and assessed their effects on cell viability, reactive oxygen species (ROS) production, anti-senescence properties (expression of senescence-associated β galactosidase and p21 mRNA), and expression of pro-inflammatory genes (CXCL-1, IL-6, TNF-α) and inflammation-related proteins (IL-8, IL-15, RANTES, MIF). The highest non-toxic concentration of 18βGA-PLGA nanoparticles to healthy human broncho epithelial cell line BCiNS1.1 was identified as 5 µM. These nanoparticles effectively mitigated cigarette smoke-induced inflammation, reduced ROS production, protected against cellular aging, and counteracted the effects of CSE on the expression of the inflammation-related genes and proteins. This study underscores the potential of 18βGA encapsulated in PLGA nanoparticles as a promising therapeutic approach to alleviate cigarette smoke-induced oxidative stress, inflammation, and senescence. Further research is needed to explore the translational potential of these findings in clinical and in vivo settings.

The interplay between rheumatic diseases and pulmonary health

Patients with rheumatic diseases (RDs) are prone to a number of comorbidities, particularly those affecting the respiratory system due to inflammatory and autoimmune mechanisms. Rheumatoid arthritis (RA), systemic sclerosis (SSc), and inflammatory idiopathic myopathies (IIMs) often present with progressive interstitial lung disease (ILD). The prevalence of ILD varies among patients with RDs, with 11% in RA, 47% in SSc, and 41% in IIMs. Some diagnostic markers, including KL-6, cytokines TNF-α and IL-6, and autoantibodies (anti-CCP), play a crucial role in assessing and predicting the course of pulmonary involvement in RDs. Lung fibrosis is a progressive disorder in SSc and RA, limiting the effiency of therapeutic interventions. Re-evaluating treatment approaches with disease-modifying anti-rheumatic drugs (DMARDs) is crucial for understanding their impact on the risk of lung affections. Despite initial concerns surrounding methotrexate, recent evidence points to its benefits in RA-associated interstitial lung disease (RA-ILD). Recognizing the intricate relationship between autoimmune RDs and lung affections is crucial for formulating effective treatment strategies. Emphasis is placed on collaborative efforts of rheumatologists and pulmonologists for early diagnosis, comprehensive care, and optimal patient outcomes in RA-ILD.

Elastin-derived peptides favor type 2 innate lymphoid cells in chronic obstructive pulmonary disease

Chronic obstructive pulmonary disease (COPD) is a condition characterized by chronic airway inflammation and obstruction, primarily caused by tobacco smoking. Although the involvement of immune cells in COPD pathogenesis is well established, the contribution of innate lymphoid cells (ILCs) remains poorly understood. ILCs are a type of innate immune cells that participate in tissue remodeling processes, but their specific role in COPD has not been fully elucidated. During COPD, the breakdown of pulmonary elastin generates elastin peptides that elicit biological activities on immune cells. This study aimed to investigate the presence of ILC in patients with COPD and examine the impact of elastin peptides on their functionality. Our findings revealed an elevated proportion of ILC2 in the peripheral blood of patients with COPD, and a general activation of ILC as indicated by an increase in their cytokine secretion capacity. Notably, our study demonstrated that serum from patients with COPD promotes ILC2 phenotype, likely due to the elevated concentration of IL-5, a cytokine known to favor ILC2 activation. Furthermore, we uncovered that this increase in IL-5 secretion is partially attributed to its secretion by macrophages upon stimulation by elastin peptides, suggesting an indirect role of elastin peptides on ILC in COPD. These findings shed light on the involvement of ILC in COPD and provide insights into the potential interplay between elastin breakdown, immune cells, and disease progression. Further understanding of the mechanisms underlying ILC activation and their interaction with elastin peptides could contribute to the development of novel therapeutic strategies for COPD management.NEW & NOTEWORTHY Elastin-derived peptides, generated following alveolar degradation during emphysema in patients with COPD, are able to influence the response of type 2 innate lymphoid cells. We show that the orientation of innate lymphoid cells in patients with COPD is shifted toward a type 2 profile and that elastin peptides are indirectly participating in that shift through their influence of macrophages, which in turn impact innate lymphoid cells.

Unwinding circular RNA's role in inflammatory pulmonary diseases

Circular RNAs (circRNAs) have emerged as pivotal regulators of gene expression and cellular processes in various physiological and pathological conditions. In recent years, there has been a growing interest in investigating the role of circRNAs in inflammatory lung diseases, owing to their potential to modulate inflammation-associated pathways and contribute to disease pathogenesis. Inflammatory lung diseases, like asthma, chronic obstructive pulmonary disease (COPD), and COVID-19, pose significant global health challenges. The dysregulation of inflammatory responses demonstrates a pivotal function in advancing these diseases. CircRNAs have been identified as important players in regulating inflammation by functioning as miRNA sponges, engaging with RNA-binding proteins, and participating in intricate ceRNA networks. These interactions enable circRNAs to regulate the manifestation of key inflammatory genes and signaling pathways. Furthermore, emerging evidence suggests that specific circRNAs are differentially expressed in response to inflammatory stimuli and exhibit distinct patterns in various lung diseases. Their involvement in immune cell activation, cytokine production, and tissue remodeling processes underscores their possible capabilities as therapeutic targets and diagnostic biomarkers. Harnessing the knowledge of circRNA-mediated regulation in inflammatory lung diseases could lead to the development of innovative strategies for disease management and intervention. This review summarizes the current understanding of the role of circRNAs in inflammatory lung diseases, focusing on their regulatory mechanisms and functional implications.

Nanocurcumin supplementation improves pulmonary function in severe COPD patients: A randomized, double blind, and placebo-controlled clinical trial

Considering the anti-inflammatory properties of curcumin, the present study was designed to investigate the effect of nano-curcumin on respiratory indices and interleukin-6 (IL-6) levels in severe chronic obstructive pulmonary disease (COPD) patients as a common pulmonary disease causing restricted airflow and breathing problems. In the current double-blind placebo-controlled randomized clinical trial study, 60 patients with stages 3 and 4 COPD were randomly assigned into 80 mg nano-curcumin (n = 30) and placebo groups (n = 30) for 3 months. The effect of nano-curcumin on pulmonary function was evaluated by the first second of forced expiration (FEV1) to the full, forced vital capacity (FVC) ratio. IL-6 serum level, blood pressure, and anthropometric indices were also measured. Nano-curcumin supplementation led to a significant decrease in IL-6 level (p < 0.001) and an increase in FEV1 (p < 0.001), FVC (p = 0.003), and FEV1/FVC (p < 0.001) compared to placebo at the endpoint. Nano-curcumin had a significantly increasing effect on weight and body mass index compared to the placebo group (PANCOVA adjusted for baseline values  = 0.042). There was a meaningful improvement in systolic blood pressure in the nano-curcumin group compared to the placebo group (PANCOVA adjusted for baseline values  = 0.026). There was no significant difference between the two groups in terms of waist circumference, waist-to-hip ratio, and diastolic blood pressure (PANCOVA adjusted for baseline values >0.05). Nano-curcumin supplement seems to have favorable effects on inflammation status and respiratory indices of patients with severe COPD.

A systematic review and meta-analysis to evaluate blood levels of interleukin-6 in lung cancer patients

Introduction

The exact mechanism responsible for inflammation in malignancy is not completely understood, but it is possible that interleukin-6 (IL-6) plays a major role in triggering and maintaining an inflammatory response.

Aim

To conduct a systematic review and meta-analysis of the levels of IL-6 in the serum/plasma of lung cancer (LC) patients.

Material and methods

The researchers searched four databases up to September 11, 2022, to find studies that reported on IL-6 levels in LC patients compared to healthy controls (HCs). They calculated effect sizes using standardized mean difference (SMD) with a 95% confidence interval (CI). To evaluate the quality of each study, they used the Newcastle-Ottawa Scale (NOS). They performed subgroup analysis, sensitivity analysis, meta-regression analysis, heterogeneity analyses, trial sequential analysis, and publication bias with the trim-and-fill method.

Results

The meta-analysis included 28 studies, and the results showed that the pooled SMD was 1.71 (95% CI: 1.22, 2.19; p < 0.00001; I2 = 98%), indicating that LC patients had significantly higher levels of IL-6 in their serum/plasma than HCs.

Conclusions

The study found that the publication year and quality score of the studies were positively associated with the level of IL-6, while the sample size was inversely related. The research suggests that measuring IL-6 levels in the blood could be useful for detecting and monitoring LC as it appears to be a reliable biomarker.

Elevated Levels of Interleukin-1β and Interleukin-10 Are Associated With Faster Lung Function Decline in People With Well-Treated Human Immunodeficiency Virus

BACKGROUND

People with human immunodeficiency virus (PWH) have an increased risk of chronic lung diseases and chronic inflammation. We aimed to investigate if inflammatory markers and monocyte activation are associated with faster lung function decline in PWH.

METHODS

We included 655 PWH from the Copenhagen Comorbidity in HIV Infection (COCOMO) Study. Eligible participants were aged ≥25 years and had 2 spirometries separated by >2 years. Inflammatory markers (interleukin [IL]-1β, IL-2, IL-6, IL-10, tumor necrosis factor-α, and interferon-γ) were measured at baseline by Luminex, and soluble CD14 and soluble CD163 by enzyme-linked immunosorbent assay. Using linear mixed models, we investigated whether elevated cytokine levels were associated with faster lung function decline.

RESULTS

The majority of PWH were males (85.2%) with undetectable viral replication (95.3%). We found a faster decline in forced expiratory volume in 1 second (FEV1) in PWH with elevated IL-1β and IL-10, with an additional decline of 10.3 mL/year (95% confidence interval [CI], 2.1-18.6; P = .014) and 10.0 mL/year (95% CI, 1.8-18.2; P = .017), respectively. We found no interaction between smoking and IL-1β or IL-10 on FEV1 decline.

CONCLUSIONS

Elevated IL-1β and IL-10 were independently associated with faster lung function decline in PWH, suggesting that dysregulated systemic inflammation may play a role in the pathogenesis of chronic lung diseases.

Roles of Omega-3 Polyunsaturated Fatty Acids in Managing Cognitive Impairment in Chronic Obstructive Pulmonary Disease: A Review

Chronic obstructive pulmonary disease (COPD) contributes significantly to the death of people worldwide, especially the elderly. An essential feature of COPD is pulmonary inflammation, which results from long-term exposure to noxious substances from cigarette smoking and other environmental pollutants. Pulmonary inflammatory mediators spill over to the blood, leading to systemic inflammation, which is believed to play a significant role in the onset of a host of comorbidities associated with COPD. A substantial comorbidity of concern in COPD patients that is often overlooked in COPD management is cognitive impairment. The exact pathophysiology of cognitive impairment in COPD patients remains a mystery; however, hypoxia, oxidative stress, systemic inflammation, and cerebral manifestations of these conditions are believed to play crucial roles. Furthermore, the use of medications to treat cognitive impairment symptomatology in COPD patients has been reported to be associated with life-threatening adverse effects, hence the need for alternative medications with reduced side effects. In this Review, we aim to discuss the impact of cognitive impairment in COPD management and the potential mechanisms associated with increased risk of cognitive impairment in COPD patients. The promising roles of omega-3 polyunsaturated fatty acids (ω-3 PUFAs) in improving cognitive deficits in COPD patients are also discussed. Interestingly, ω-3 PUFAs can potentially enhance the cognitive impairment symptomatology associated with COPD because they can modulate inflammatory processes, activate the antioxidant defence system, and promote amyloid-beta clearance from the brain. Thus, clinical studies are crucial to assess the efficacy of ω-3 PUFAs in managing cognitive impairment in COPD patients.

The correlation between a Th1/Th2 cytokines imbalance and vitamin D level in patients with early chronic obstructive pulmonary disease (COPD), based on screening results

Objective: This study explored the correlation between a Th1/Th2 cytokines imbalance and 25-hydroxy-vitamin D (vit D) level in early chronic obstructive pulmonary disease (COPD), provided experimental rationales for the role of vit D in the prevention and control of COPD, and elucidated the potential anti-inflammatory mechanism involved.

Methods: This study was based on the results of the “Screening and Early Diagnosis of COPD” public health project conducted through Shenzhen Municipal Qianhai Shekou Free Trade Zone Hospital. Patients with early COPD were selected as study participants. A prospective, randomized, and controlled method was employed for assigning eligible participants into three groups, i.e., a COPD lung function (LF) I, COPD LF II, and a healthy group, respectively (n = 40 each). The serum content of tumor necrosis factor alpha (TNF-α), interferon-gamma (IFN-γ), interleukin 4 (IL-4), and IL-6 were measured by enzyme-linked immunosorbent assay, and the ratio of IFN-γ/IL-4 treated as a marker for Th1/Th2. The serum concentration of 25-hydroxyl-vit D (25 [OH]D) was quantified by a chemiluminescence assay. Statistical processing was performed, and the correlations between changes in the above parameters with vit D level and LF parameters were examined.

Results: There were differences in FEV1pred%, FEV1/FVC, IFN-γ, IL-4, IL-6 and IFN-γ/IL-4 between the healthy group, the COPD LF I group and the COPD LF II group (p &lt; 0.05). In early COPD, Th1/Th2 cytokines was positively correlated with forced expiratory volume/expected value (FEV1pred%) (r = 0.485, p &lt; 0.001) and forced expiratory volume/forced vital capacity (FEV1/FVC) (r = 0.273, p = 0.018); Th1/Th2 cytokines levels positively correlated with vit D level (r = 0.27, p = 0.02), and 25(OH)D level positively correlated with FEV1pred% (r = 0.695, p &lt; 0.001).

Conclusion: Vitamin D deficiency was ubiquitous in patients with early COPD. It was positively correlated with the FEV1pred% and FEV1/FVC LF parameters. Accordingly, this study provides experimental rationales for the role of vit D in the prevention and control of COPD and the potential anti-inflammatory mechanisms involved.

Adiponectin Increase in Patients Affected by Chronic Obstructive Pulmonary Disease with Overlap of Bronchiectasis

Chronic obstructive pulmonary disease (COPD) is characterized by respiratory symptoms and non-reversible airflow limitation with recurrent episodes of acute exacerbations. The concurrent presence of bronchiectasis in patients with COPD is associated with reduced respiratory function as well as increased exacerbation risk. Adiponectin is a promising biomarker in COPD, as greater high molecular weight (HMW) oligomer levels have been observed among COPD patients. Here, we investigate adiponectin levels in two groups of COPD patients characterized by the presence or absence of bronchiectasis (BCO), comparing both groups to healthy controls. We evaluated serum adiponectin levels in COPD patients, those with BCO, and healthy subjects and characterized the pattern of circulating adiponectin oligomers. We found that forced volume capacity % (FVC%) and forced expiratory volume % (FEV1%) were lower for BCO patients than for COPD patients. COPD patients had higher levels of adiponectin and its HMW oligomers than healthy controls. Interestingly, BCO patients had higher levels of adiponectin than COPD patients. We showed that expression levels of IL-2, -4, and -8, IFN-γ, and GM-CSF were significantly higher in BCO patients than in healthy controls. Conversely, IL-10 expression levels were lower in BCO patients. Our data suggest that the increased levels of adiponectin detected in the cohort of BCO patients compared to those in COPD patients without bronchiectasis might be determined by their worse airway inflammatory state. This hypothesis suggests that adiponectin could be considered as a biomarker to recognize advanced COPD patients with bronchiectasis.

The prospective relationship between subjective aging and inflammation: Evidence from the health and retirement study

This study tested the prospective associations and potential mediators between subjective aging, indexed by subjective age and self-perceptions of aging (SPA), and a range of inflammatory markers, including C-reactive proteins (CRP) and pro- and anti-inflammatory cytokines among older adults. Participants (N = 6099, 59% women, age range = 50 to 94, Mean Age = 65.32, SD = 8.85) were drawn from the Health and Retirement Study. Subjective age, SPA, and demographic factors were assessed in 2008/2010. Assessments of soluble transformation growth factor-beta 1 (sTGF-β1), interleukin 10 (IL-10), interleukin-1 receptor antagonist (IL-1Ra), interleukin 6 (IL-6), soluble tumor necrosis factor receptors (sTNFR1), and high sensitivity CRP (hsCRP) were measured in 2016. Potential mediators (body mass index, disease burden, physical inactivity, and depressive symptoms) were asssessed at baseline and in 2012/2014. Linear regression analyses indicated that an older subjective age and negative SPA were related to higher level of IL-10, IL-1Ra, IL-6, sTNFR1 and hsCRP. These associations were mediated by higher disease burden and physical inactivity. Negative SPA (but not subjective age) was associated with lower sTGF-β1. The link between subjective aging and inflammatory markers was relatively independent from chronological age. The present study provides new evidence that subjective aging is prospectively associated with inflammation, including systemic inflammation and pro-and anti-inflammatory cytokines.

The use of interleukin-6 as a biomarker of lung cancer: A systematic review and meta-analysis

BACKGROUND

Lung cancer is known for its fatality due to diagnosis at a late stage, indicating the need for the discovery of novel diagnostic biomarkers. Interleukin-6 (IL-6) belongs to a family of inflammatory cytokines shown to be elevated in cancer patients. Hence, in this study, a systematic review and meta-analysis was undertaken to evaluate the association of IL-6 levels between lung cancer patients and healthy individuals, as this would further support its use as a clinical biomarker.

METHODS

All major electronic databases were systematically searched to find the existing literature from 2012 until September 2022 on the association of IL-6 levels with lung cancer. Mean and standard deviation of IL-6 levels of lung cancer patients and controls were recorded from the included case-control studies. The natural logarithm of the ratio of means (RoM) between patients and controls with its respective 95% confidence intervals was calculated to retrieve a pooled RoM value.

RESULTS

Eight studies involving 559 lung cancer patients and 462 healthy controls were in included in the meta-analysis and a random-effects model was used due to high heterogeneity (I2 = 99.38%). Overall, IL-6 was found to be higher in lung cancer patients (pooled ln RoM = 1.20, 95% CI: 0.72-1.69, P < 0.0001) and all included studies were found to carry a low risk of bias after quality assessment.

CONCLUSIONS

This meta-analysis revealed that IL-6 levels are higher in biological samples of lung cancer patients, indicating that they could be used as a biomarker for diagnosing lung cancer without complications. Further research should be undertaken to evaluate its diagnostic accuracy, in order to obtain more concrete evidence for its clinical use.

Lung Pneumonitis and Fibrosis in Cancer Therapy: A Review on Cellular and Molecular Mechanisms

Fibrosis and pneumonitis are the most important side effects of lung tissue following cancer therapy. Radiotherapy and chemotherapy by some drugs, such as bleomycin, can induce pneumonitis and fibrosis. Targeted therapy and immunotherapy also may induce pneumonitis and fibrosis to a lesser extent compared to chemotherapy and radiotherapy. Activation of lymphocytes by immunotherapy or infiltration of inflammatory cells such as macrophages, lymphocytes, neutrophils, and mast cells following chemo/radiation therapy can induce pneumonitis. Furthermore, the polarization of macrophages toward M2 cells and the release of anti-inflammatory cytokines stimulate fibrosis. Lung fibrosis and pneumonitis may also be potentiated by some other changes such as epithelial-mesenchymal transition (EMT), oxidative stress, reduction/oxidation (redox) responses, renin-angiotensin system, and the upregulation of some inflammatory mediators such as a nuclear factor of kappa B (NF-κB), inflammasome, cyclooxygenase-2 (COX-2), and inducible nitric oxide synthase (iNOS). Damages to the lung vascular system and the induction of hypoxia also can induce pulmonary injury following chemo/radiation therapy. This review explains various mechanisms of the induction of pneumonitis and lung fibrosis following cancer therapy. Furthermore, the targets and promising agents to mitigate lung fibrosis and pneumonitis will be discussed.

Clinical Value of Cytokine Assay in Diagnosis and Severity Assessment of Lung Cancer

Purpose

To investigate the clinical value of interleukin 2 (IL-2), interleukin 4 (IL-4), interleukin 6 (IL-6), interleukin 10 (IL-10), tumor necrosis factor α (TNF-α), and interferon-γ (IFN-γ) in diagnosis and severity assessment of lung cancer.

Methods

In this observational study, 50 physical examination healthy subjects were included in the control group and 100 lung cancer patients were included in the study group. In the study group, 53 cases with pleural effusion were subgrouped to the pleural effusion group (n = 53), while 47 patients were assigned to the nonpleural effusion group (n = 47). Plasma cytokines IL-2, IL-4, IL-6, IL-10, TNF-α, IFN-γ, and Acute Physiology and Chronic Health Evaluation II (APACHE II) scores of all eligible subjects were collected and compared.

Results

The study group showed significantly higher levels of plasma cytokines IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ versus healthy subjects (P < 0.05). Deterioration of lung cancer was associated with increased plasma cytokine levels and APACHE II scores. The combination assay of the above plasma cytokines showed significantly better diagnostic efficacy for lung cancer versus the single assay of the cytokines. Dead patients had higher plasma cytokine levels versus survived patients. The accuracy of plasma IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ levels in the severity assessment of lung cancer was comparable with that of the APACHE II scale.

Conclusion

The plasma cytokines IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ are effective markers for the diagnosis of lung cancer. The combined assay contributes to the early diagnosis of lung cancer patients, and the persistent elevation of cytokines suggests an increased risk of death in lung cancer patients, so the detection of cytokine levels facilitates the severity assessment of lung cancer.

Extracellular vesicles and chronic obstructive pulmonary disease (COPD): a systematic review

Background

Chronic Obstructive Pulmonary Disease (COPD) is a common inflammatory disease of the airways characterized by irreversible airflow limitation, ranking the third highest cause of death worldwide. Extracellular vesicles (EVs) are important intercellular communication mediators released by cells into their extracellular environment with the capacity to transfer biological signals. EVs involved in COPD hold great potential to understand disease pathogenesis and identify important biomarkers. This systematic review aims to examine all available research on EVs in the pathogenesis and diagnosis of COPD to identify existing knowledge and support further research within the field.

Methods

Publications were searched using PubMed and EMBASE with the search terms (Exosomes or extracellular vesicles or microvesicles or microparticles or ectosomes) AND (chronic obstructive pulmonary disease or COPD or emphysema or bronchitis).

Results

Initial search yielded 512 papers of which 142 were manually selected for review and 43 were eligible for analyses. The studies were divided into groups according to the role of EVs in pathogenesis, EV origin and cargo, their role in COPD exacerbations and their diagnostic utility. EVs were found to be involved in the mechanism of pathogenesis of COPD, derived from various cell types, as well as containing modified levels of miRNAs. EVs also varied according to the pathophysiological status of disease, therefore presenting a possible method for COPD diagnosis and progress monitoring.

Conclusion

The current findings show the limited but good quality research looking at the role of EVs in COPD, demonstrating the need for more studies to better define and provide further insight into the functional characteristics of EV in COPD pathogenesis.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12931-022-01984-0.

Role of Toll-Like Receptor 2 in Regulation of T-Helper Immune Response in Chronic Obstructive Pulmonary Disease

Objective

According to modern views, the differences in the clinical course of chronic obstructive pulmonary disease (COPD) are associated with certain types of T-helper (Th) immune response. Recent data have shown that toll-like receptor 2 (TLR2) is involved in the development of Th immune response. However, TLR2-mediated regulation of Th subpopulation balance in COPD needs to be elucidated. The aim of our work is to determine the mechanisms of TLR2-mediated regulation of Th immune response in COPD of varying severity.

Methods

The study included 323 smokers/ex-smokers with stable COPD (GOLD I, GOLD II, and GOLD III) and 97 healthy nonsmokers (control group). Serum levels of Th1 (TNF-α and IFN-γ), Th2 (IL-4), Th17 (IL-6 and IL-17A), Treg (IL-10) cytokines, and the percentage of peripheral blood Th cells expressing TLR2 (CD4⁺CD282⁺) were assessed by flow cytometry. Serum concentrations of IL-21 (Th17) and TGF-β1 (Treg) were measured using the ELISA method. The predominant Th cytokine profile in serum was determined by calculating the ratios between levels of Th1 and Th17 cytokines. Spearman's correlation test was performed.

Results

Patients with COPD GOLD II and III with Th1 and Th17 cytokine profiles exhibited an increase in the percentage of CD4⁺CD282⁺ cells compared to the control group. In COPD GOLD I–III, positive correlations between CD4⁺CD282⁺ cell frequency and Th17 cytokine levels (IL-6, IL-17A, and IL-21) were found. In COPD GOLD I, IL-10 concentration was negatively correlated with the percentages of studied cells; in COPD GOLD II, a positive correlation between these parameters was noted.

Conclusions

Enhanced TLR2 expression on CD4⁺ cells shifts cytokine profile toward Th17 phenotype that plays a crucial role in COPD progression. The level of TLR2 expression on peripheral blood CD4⁺ cells may be considered as a biomarker for diagnosing and predicting the progression of COPD.