CircRNA0001859, a new diagnostic and prognostic biomarkers for COPD and AECOPD

Abstract

Background: Dysregulation of circRNAs has been reported to be functionally associated with chronic obstructive pulmonary disease (COPD). The present investigation elucidated the potential role of CircRNA0001859 in regulating chronic obstructive pulmonary disease acute (COPD) and Acute Exacerbation of COPD (AECOPD).

Methods: Mice model of COPD was established to screen and verify the dysregulated expression of CircRNA0001859. Fluorescence in situ hybridization (FISH) and quantitative real-time PCR (qRT-PCR) were carried out to detect the expression of CircRNA0001859. 38 stable COPD patients, 24 AECOPD patients, 57 COPD with lung cancer patients and 28 healthy person with age and sex matched to total patients were used for the present investigation.

Results: circRNA0001859 was downregulated in the lung tissue of mice after the three kinds of treatments (Cigarette smoke (CS)/NK alone or CS + NNK) for inducing COPD. FISH assay verified the downregulation of circRNA0001859 both in the mice lung and human bronchial epithelial cell of COPD model. Furthermore,, the level of circRNA0001859 was also downregulated in the peripheral blood of COPD and lung cancer patients. CircRNA0001859 might act as a diagnostic and prognostic biomarker for the treatment of in COPD and AECOPD with Are under the receiver operating characteristic curve (ROC curve) (AUC) of 0.7433 and 0.8717, respectively.

Conclusion: We explored a novel circRNA0001859, which might act as a potential therapeutic biomarker for the treatment of COPD and AECOPD.

Keywords: Acute exacerbation of COPD (AECOPD); CS; Chronic obstructive pulmonary disease (COPD); Circular RNA0001859 (CircRNA0001859); Lung cancer; NNK.

Fig. 1

The evaluation of the animal model establishment. a HE staining was used to detect the pathological changes in lung tissues (× 200, n = 8). b Lung function parameters including FEV0.1, Cydn and Raw were evaluated. c Inflammatory cytokines such as IL-6, TNF-α and IL-10 in BALF were detected using ELISA (n = 8). d Oxidative stress related cytokines including MDA, SOD and GSH were evaluated using ELISA assay (n = 8). e Cell counts of total cell, mononuclear cell and neutrophils in BALF were carried out (n = 8). f. IHC was performed to evaluate the expression of ki67 in lung tissue (× 100, n = 8). *p < 0.05, **p < 0.01. Three independent biological repeats were carried out for each analysis

Fig. 2

CircRNA0001859 was down-regulated in lung tissue of COPD mouse. a The dysregulated expression of circRNAs in CS treatment group as compared with the Air treatment group. b The dysregulated expression of circRNAs in NNK treatment group as compared with the Air treatment group. c The dysregulated expression of circRNAs in CS + NNK treatment group as compared with the Air treatment group. d The Venn diagram showed the dysregulated circRNA after all the three kinds of treatments (CS/NK alone or CS + NNK). Three independent biological repeats were carried out for each analysis

Fig. 3

CircRNA0001859 was downregulated in lung tissue of COPD mouse. a FISH assay with Alexa Fluor 555-labeled circRNA0001859 probe was performed to evaluate the expression of circRNA0001859 in the lung tissue (× 200, n = 6). b qRT-PCR was used to evaluate the expression of circRNA0001859 in the lung tissue (n = 6). *p < 0.05. Three independent biological repeats were carried out for each analysis

Fig. 4

CircRNA0001859 was downregulated in human bronchial epithelial cell subjected to CS/NNK or CS + NNK treatment. FISH assay was performed to evaluate the expression of circRNA0001859 in the human bronchial epithelial cell subjected to three different treatments (× 200, n = 6). b qRT-PCR was used to evaluate the expression of circRNA0001859 in the lung tissue (n = 6). *p < 0.05. Three independent biological repeats were carried out for each analysis

Fig. 5

CircRNA0001859 was downregulated in serum obtained from COPD, AECOPD and lung cancer with COPD patients and mice serum treated by CS/NNK alone or CS + NNK. a IL-6 and b TNF-α were evaluated using ELISA (n = 6). qRT-PCR was performed to evaluate the expression of circRNA0001859 in the blood of patients (c) or mice (d) (n = 6). *p < 0.05. Three independent biological repeats were carried out for each analysis

Fig. 6

CircRNA0001859 expression level was correlated with the transformation from COPD to lung cancer. Spearman correlation analysis was carried out between FEV1/FVC% and circRNA0001859 expression in blood of (a) CDOP and (b) AECOPD patients. c ROC curve analysis of circRNA0001859 expressions for predicting stable COPD risk from HCs; d ROC curve analysis of circRNA0001859 expressions for predicting AECOPD risk from HCs. Three independent biological repeats were carried out for each analysis