Diversity Of Lower Respiratory Tract Related Microorganisms In Patients With Lung Squamous Carcinoma Or Lung Adenocarcinoma

Purpose:More and more studies have shown that microorganisms of lower respiratory tract plays an important role in the development of lung diseases,and the colonization of bacteria in the trachea and bronchi forms a symbiotic relationship with the host.Lung cancer is a malignant tumor with the highest mortality in the world,and most of the patients are lung squamous cell carcinoma or lung adenocarcinoma.However,there is still no rapid and accurate diagnostic method for lung squamous cell carcinoma and lung adenocarcinoma.The purpose of this study is to reveal the distribution and composition of lower respiratory tract microorganisms in lung squamous cell carcinoma and lung adenocarcinoma,and to investigate the correlation between lower respiratory tract microorganisms and lung cancer,which can provide an important reference for the prevention and early diagnosis of lung cancer.Methods:This study will apply the high-throughput sequencing technology to distinguish 16S rDNA V3-V4 variable region,which samples collected from 11 healthy volunteers and 28 patients with non-small cell lung cancer(including lung adenocarcinoma 12,squamous cell lung cancer 16)in Yunnan Province.We collected the samples by the electronic bronchoscope.Then those samples were sequenced by Miseq sequencing.When we obtain the sequence and compared the sequencing results of microorganisms in the lower respiratory tract between healthy volunteers and non-small cell lung cancer patients.Results:In this study,we obtained a total of 3,629,338 high quality 16SrRNA gene sequences(healthy individuals were obtained 2,035,496 sequences,and the patients with lung adenocarcinoma were obtained 688,396 sequences,and the patients with squamous cell carcinoma of the lung were obtained 905,446 sequences).Each sample of healthy people averaged 37009.02±4853.4541 sequeces,each sample of the lung adenocarcinoma’s patients averaged 28683.17±5281.605 sequeces,each sample of lung squamous cell carcinoma’s patients averaged 30181.53±4316.73 sequeces.According to the similarity of 97%taxa(Operational taxonomic OTU units.OTUs)clustering(excluding single sequence and chimera),that we were obtained OTUs:healthy people received a total of 1,641,035 OTUs,the average OTUs number of each sample was 29,837 OTUs;lung adenocarcinoma patients received a total of 408,744 OTUs,the average OTUs number of each sample was 17,031 OTUs;the patients with squamous cell carcinoma of lung received a total of 510,930 OTUs,the average number of each sample is 17,031 OTUs(Data has been optimized).All identified bacterial OTUs can be classified into 31 bacterial taxa,the most dominant bacterial phylum in the lower respiratory tract is Firmicutes,and also there was a small number of Proteobacteria(Proteobacteria).The lower respiratory tract of healthy have colonizated microorganisms,and whether the left and right lung or the different lobi pulmonis of lung,the distribution of each part is not significant.Compared with the known literature,microorganisms colonization in the lower respiratory tract are obviously different in Yunnan Province and abroad.Then compared healthy people and the patients with lung squamous cell carcinoma or lung adenocarcinoma,we found that there are significant difference from colonizated microorganisms.The microorganisms of lower respiratory tract in patients with lung cancer increased the bacterial diversity,and the opportunistic pathogen relative abundance increased and probiotic reduced significantly.In addition,we also compared lower respiratory tract microorganisms composition between lung adenocarcinoma and squamous cell carcinoma.We found that there were significant differences in the lower respiratory tract microorganisms between lung adenocarcinoma and lung squamous cell carcinoma,and the composition of microorganisms was significantly different.Conclusions:We think that the health lung(the lower respiratory tract)colonizated microorganisms.Nevertheless,different regions may have different microorganisms colonization.It may exist regional difference.The bacterial diversity of the lower respiratory tract about patients with lung adenocarcinoma or lung squamous cell carcinoma was increased and numbers of opportunistic pathogen had significant increase,as well as the environment of lung had changed which acid-base was imbalance.Different types,or different causes of lung cancer,the microorganisms in the lower respiratory tract is significantly different.In the future we can aim at different causes of lung cancer targeted,and achieved the personalized treatment.