Mechanism Of LncRNA Rp11-521C20.3-BMF Signaling Pathway In COPD Alveolar Epithelial Cell Apoptosis

Objective(s):Chronic obstructive pulmonary disease(Chronic Obstructive Pulmonary Disease,COPD)in addition to a variety of environmental impacts,more affected by genetic factors,this study uses gene chips to detect COPD patients peripheral blood lncRNA and mRNA expression profiles,To construct differential expression profiles of lncRNA and mRNA in COPD patients.Bioinformatics technology is used to predict the biological function of differentially expressed lncRNA and its target genes.At the same time,RT-qPCR is used to verify the expression levels of lncRNA and its target mRNA,and to explore the possible molecular mechanisms involved in the pathogenesis of COPD.Methods:We selected 3 smoking COPD patients admitted in the Department of Respiratory Medicine,Kunming Medical University First Affiliated Hospital in January 2017 as the experimental group,and the control group selected 3 healthy smoking volunteers with normal lung function tests.Early morning fasting venous blood was collected from all subjects.The differential expression of lncRNAs and mRNAs in the blood of COPD patients with smoking history(n=3)and healthy control group(n=3)was detected by human microarray technology.Then,using gene ontology(GO)analysis and genomic encyclopedia(KEGG)approach,the differentially expressed lncRNAs and mRNAs were analyzed to discover the biological pathways that differentially expressed genes may participate in.Next,we collected 50 early-morning fasting blood samples from COPD patients with a history of smoking who were hospitalized in the Respiratory Department of the First Affiliated Hospital of Kunming Medical University from January to December 2017.The qPCR method further verified the expression levels of lncRNA and mRNA in the pre-chip.Then collected 5 cases of distant cancer tissues with smoking COPD combined with lung cancer,and pneumothorax tissues without COPD,and further verified the expression of lncRNA rp11-521C20.3 and BMF(Bcl-2 modifying factor)at the tissue level.Results:Through microarray technology,it was found that there are a large number of differentially expressed lncRNA and mRNA in the peripheral blood of COPD patients and healthy smokers.There are a total of 3359 lncRNAs in the two groups,of which 1995 lncRNAs are up-regulated in copd and 1364 lncRNAs are down-regulated;The chip test results indicated that there were a total of 175 mRNA expression differences between the COPD group and the control group,of which 147 were up-regulated and 28 were down-regulated.Bioinformatics analysis suggests that differentially expressed mRNAs are mainly involved in various biological processes of COPD,including inflammation and metabolism.There are 7 kinds of mRNAs with large differences and may be related to the occurrence and development of COPD,including:BMF,TRIM13,PDE4B,MYL-9,PFKFB3,ARIH2,CLEC2B,etc.,search in the lncRNA-mRNA position correspondence table,and finally only Obtaining lncRNA rp11-521 C20.3 that has an antisense relationship with the BMF gene position may play an important role in BMF gene transcription and translation.Verification by qRT-PCR in 50 cases of human peripheral blood showed that the relative expression level of RP11-521 C20.3 in the smoking COPD group(Chronic COPD group 2^-?CT=0.357)was lower than that of the smoking healthy control group The expression level(control group 2^-? CT=1),that is,RP11-521C20.3 was down-regulated in COPD group.The relative expression of BMF in the smoking COPD group(Chronic COPD group 2^-? CT=1.924)was higher than that of the control group(Control group 2^-? CT=1),that is,mRNA in COPD The expression was up-regulated in the group.Therefore,the relative expression levels of lncR-RP1-521C20.3 and BMF were statistically significant between the case group and the control group(P<0.05).Using qRT-PCR to verify the expression of lncR-RP11-521 C20.3 and BMF in the lung tissues of the two groups of patients,the results showed that the mRNA expression of BMF in the lung tissue of the COPD group was higher than that of the control group,and the positional relationship of lncRNA RP11-521C20.3 was down-regulated,and the difference in expression levels of BMF and lncR-RP11-521C20.3 between the two groups was statistically significant(P<0.05).Further validated the results of the previous gene chip.