CT Imaging Characteristics And Circular RNA Expression Profile Of Lung Adenocarcinoma

Objective:1.To analyze the imaging findings of different pathologic subtypes of lung adenocarcinoma with ground-glass opacity on thin-section CT.To compare the imaging features of invasive lesions and pre-infiltrating lesions,and to provide evidence for the imaging evaluation of lung adenocarcinoma with ground-glass opacity.2.To investigate the circRNA expression pattern in lung adenocarcinoma revealed by Microarray Analysis.To laid the foundation for further study of the function of certain specific circRNA in lung cancer.Methods:1.68 cases of ground glass nodules?GGNs?were collected including preinvasive lesions?atypical adenomatous hyperplasia 14 cases and adenocarcinoma in situ21 cases?,minimally invasive adenocarcinoma?MIA?15 cases and invasive adenocarcinoma?IAC?18 cases;CT manifestations were analyzed including lesion location,size,solid component,shape,margin,tumor-lung interface,internal and surrounding malignant sign.Measurement data using single factor analysis of variance,count data by Fisher's exact test.The sizes of preinvasive and invasive lesions were assessed using ROC curves.2.4 tumors and paired adjacent normal tissues of lung adenocarcinoma were selected for the microarray analysis of circRNAs,the circRNAs with differental expression were screened out.To confirm the microarray data,we randomly selected five differentially expressed circRNAs,including two up-regulated and three down-regulated circRNAs to perform the qRT-PCR analysis in both tumour tissues and lung cancer cell lines?A549 & H1299?.Then the circRNA and miRNA interactions were predicted by using Arraystar's home-made miRNA target prediction software.Results:1.There were no statistical differences in ages,gender,lesion location,history of smoking between pathological types.There was a significant statistical difference in lesion size,shape,solid component,margin,pleural indentation,air bronchogram and adjacent vascular morphology between pathological types.The ROC curve showed that the optimal cutoff points of the maximal axial diameter and the maximum diameter in cranial-caudal direction were 10.6mm and 9.7mm respectively.2.A total of 356 dysregulated circRNAs are found in lung adenocarcinoma compared with normal tissues,among which 204 were up-regulated and 152 were down-regulated.Randomly selected 5 circRNAs were successfully verified by qRT-PCR in tumour tissues,but the expression of hsa_circRNA₄06483 and hsa_circRNA₀01640 in the lung cancer cell lines did not match well with the microarray data.Differentially expressed circRNAs had corresponding miRNA binding sites.Conclusions:1.The morphological features of GGN have a certain predictive value for pathologic classification.The spiculation sign is a reliable index for predicting GGN for invasive lesions.The size of GGN and the solid content of nodule have a high value in evaluating the infiltration of lung adenocarcinoma.2.We analyzed and validated the differential expression profiles of circRNA in lung adenocarcinoma,and these differentially expressed genes may present new molecular biomarkers associated with the development of lung adenocarcinoma or other tumors.This study also laid the foundation for further study of the function of certain specific circRNA in lung cancer.