Gene Expression Of PDGF-A,B,C And D In Malignant Pleural Effusion In Patients With Lung Adenocarcinoma

Objective: Lung cancer is one of the most common malignant tumors in the world.Lung cancer is the first tumor in terms of morbidity and mortality,the overall 5-year survival rate of about 10%-15%.According to the size and appearance of cancer cells under the microscope,cancer cells can be divided into small cell lung cancer(SCLC)and non-small cell lung cancer(NSCLC),which includes adenocarcinoma,Squamous cell carcinoma and large cell lung cancer and other subtypes.Of which non-small cell lung cancer accounts for80%-85% of lung cancer,and more than half of non-small cell lung cancer in the diagnosis is late.Pleural effusion is one of the most common clinical manifestations of advanced non-small cell lung cancer(NSCLC).Lung cancer patients with pleural effusion accounted for about 15%,of which about 50% is in the late emergence,and their prognosis is generally poor.It is a direct impact on the prognosis of patients,whether pleural effusion patients can get timely and correct diagnosis and treatment,.At present,epidermal growth factor receptor(EGFR)gene mutation inhibitors gefitinib,erlotinib and iridinib,gradient of lymphoma kinase(ALK)fusion gene deletion inhibitor tetrazolidine and other small molecule cheese(Tyrosine kinase inhibitors TKIs)have been widely used in clinical first-line or second-line treatment,so lung cancer patients with molecular targeted detection and treatment is particularly important.However,advanced lung cancer is often difficult to obtain tissue samples.the detection of EGFR and ALK gene mutation in pleural effusion was performed and according to the results to select a specific targeted drug have become normal.So we need to explore more specific genes associated with lung cancer,to detect its relationship with lung cancer,and thus select a more appropriate targeted treatment program.Platelet-derived growth factor(PDGF)is associated with the development and progression of various tumors,but there are few studies related to lung cancer.It has been reported that 32%-67% overexpressing PDGF in non-small cell lung cancer,studying on the correlation of PDGF-B chain in lung cancer tissues.In the past,a small number of scholars for lung cancer patients with PDGF research mostly taken by lung cancer tissue or blood samples.In this study,we will investigate the expression of PDGF-A,PDGFB,PDGF-C and PDGF-D in pleural effusion in patients with advanced lung adenocarcinoma.Patients with advanced lung adenocarcinoma associated with malignant pleural effusion and patients with benign pleural effusion(including pneumonia complicated with pleural effusion,tuberculous pleural effusion)PDGF-A,PDGF-B,PDGF-C,PDGF-D gene expression at gene level,suggesting that the role of PDGF in the development of lung adenocarcinoma and the possible mechanism,So as to provide a theoretical basis for the diagnosis and selection of new anticancer drugs for advanced lung adenocarcinoma with pleural effusion.In this study,we used real-time quantitative real-time PCR(PCR)to detect the expression of PDGF-A,PDGF-B,PDGF-C and PDGF-D in pleural effusion of benign lung effusion and pleural effusion(pneumonia complicated with pleural effusion and tuberculous pleural effusion),and to explore the value and significance of these four indexes in the diagnosis and treatment of malignant pleural effusion of lung adenocarcinoma according to ROC curve.Methods:Collected 70 cases of pleural effusion from March 1,2015 to December31,2017,Department of Respiratory Medicine,the Fourth Affiliated Hospital of Hebei Medical University.45 cases of lung cancer group were under the guidance of CT-guided lung puncture,bronchoscopic biopsy or pleural effusion cytology showed that patients with lung adenocarcinoma,pleural effusion were sent to the cytology of cancer cells found;control group 25 cases of benign pleural effusion patients(including pneumonia with pleural effusion,tuberculous pleurisy),pleural effusion to send out cytology did notfind cancer cells,visible mesothelial cells,lymphocytes and inflammatory cells.Extraction and preservation of patients with pleural effusion: 70 patients were collected 200-500 ml pleural effusion,centrifuged within 10 minutes,take the sediment,the cell sediment added to the 2m L storage tube,and then add RNA storage solution using Trizol reagent Quickly extract RNA,put-80℃ in the refrigerator to save.The expression of PDGF-A,PDGF-B,PDGF-C and PDGF-D in the pleural effusion of lung cancer group and control group were detected by real-time fluorescence quantitative PCR.,the relative expression was calculated using the 2-Δ ΔCTmethod.All data are processed using SPSS17.0 statistical software.Parallel statistical analysis.Result:1 lung cancer group and control group composition was no significant difference in sex and age(P> 0.05).2 Comparison of gene expression between PDGF-A,PDGF-B,PDGF-C and PDGF-D in lung cancer group and control group:There was no significant difference between the two groups on the PDGF-A(P>0.05).There was significant difference between the two groups on the PDGF-B(P<0.05).There was no significant difference between the two groups on the PDGF-C(P>0.05).There was significant difference between the two groups on the PDGF-D(P<0.05).3 ROC curve analysis of PDGF-A,PDGF-B,PDGF-C,PDGF-D: the ROC curve for the detection results,calculated the area under the curve.Which was 0.632,0.953,0.557 and 0.654.the diagnostic thresholds were3.72,3.12 about PDGF-B and PDGF-D.The sensitivity and specificity of these three indexes were 88.9% and 92%,40% and 84%,64.0%.Statistical analysis of PDGF-B and PDGF-D were statistically significant for P<0.05,PDGF-A and PDGF-C were not statistically significant for P>0.05.Conclusion:1 The expression of PDGF-B and PDGF-D in malignant pleural effusion of patients with lung adenocarcinoma was significantly increased,suggesting that PDGF-B and PDGF-D may be involved in the lung adenocarcinomametastasis process.The PDGF gene may be a new target in the treatment of lung adenocarcinoma molecular targeted therapy in the future.2 The detection of PDGF-B and PDGF-D gene expression in thoracic effusion may be a new helper test for identifying pleural effusion is benign or malignant.The diagnostic efficacy of PDGF-B is the best.