近年来，肺癌微生物菌群失调引起了极大的关注。肺微生物的研究大多基于测序，导致潜在功能菌株的极低丰度无法发现。本研究采用培养法和16S rRNA基因测序，对肺和口腔微生物群进行了表征和比较。在198个经过种水平识别的支气管肺泡灌洗液（BALF）样本中，厚壁菌门是优势菌门（39.90%）。从BALF样本中分离出的20种细菌在至少半数患者中存在，并且在口腔样本中也很丰富。其中链球菌属和维氏菌属是极高优势菌属。从口腔到肺的丰度，美沙酮菌属和维氏菌属降低，而假单胞菌属增加。线性判别分析效应大小表明，在健康样本中，美沙酮菌属比癌性患者的样本更多，这与采用培养法从健康组中仅分离出美沙酮菌属的现象一致。此外，从非小细胞肺癌（NSCLC）组中仅分离出了血红珊瑚球菌和中间链球菌，16S rRNA基因测序显示它们在NSCLC中较大。此外，肺腺癌富含芽孢杆菌和卡斯特拉尼拉菌，肺鳞癌富含布鲁氏菌。总体而言，肺癌患者微生物群落发生了变化，多样性可能取决于部位和病理学。使用培养法和16S rRNA基因插入扩增测序法，本研究为肺癌患者的肺部和口腔微生物群变化提供了深入的洞察。因此，这些特征可能成为潜在的细菌生物标志物和肺癌诊断和治疗的新靶点。此外，还建立了肺癌患者的肺和口腔微生物库，这是研究宿主-微生物相互作用的有用资源。

Recently, microbiota dysbiosis in lung cancer has attracted immense attention. Studies on lung microbes are mostly based on sequencing, which has left the potentially functional bacteria with extremely low abundance uncovered. In this study, we characterized and compared the lung and oral cavity microbiotas using culturomics and 16S rRNA gene sequencing. Of the 198 bacteria identified at the species level from bronchoalveolar lavage fluid (BALF) samples, Firmicutes was predominant (39.90%). Twenty bacterial species isolated from BALF samples were present in at least half of the patients and were also highly abundant in oral samples. Of all isolated strains, Streptococcus and Veillonella were highly dominant. The abundance of Prevotella and Veillonella decreased from the oral cavity to the lung, whereas that of Pseudomonas increased. Linear discriminant analysis effect size demonstrated that Prevotella was more abundant in the healthy samples than in the cancerous ones, which is in accordance with the isolation of Prevotella oralis only from the healthy group using culturomics. Moreover, Gemella sanguinis and Streptococcus intermedius were isolated only from the non-small-cell lung cancer (NSCLC) group, and 16S rRNA gene sequencing showed that they were higher in the NSCLC than in the small-cell lung cancer group. Furthermore, while Bacillus and Castellaniella were enriched in lung adenocarcinoma, Brucella was enriched in lung squamous cell carcinoma. Overall, alterations were observed in the microbial community of patients with lung cancer, whose diversity might be site and pathology dependent. Using culturomics and 16S rRNA gene amplicon sequencing, this study has provided insights into pulmonary and oral microbiota alterations in patients with lung cancer. IMPORTANCE The relationship between lung microbiota and cancer has been explored based on DNA sequencing; however, culture-dependent approaches are indispensable for further studies on the lung microbiota. In this study, we applied a comprehensive approach combining culturomics and 16S rRNA gene amplicon sequencing to detect members of the microbiotas in saliva and BALF samples from patients with unilateral lobar masses. We found alterations in the microbial community of patients with lung cancer, whose diversity might be site and pathology dependent. These features may be potential bacterial biomarkers and new targets for lung cancer diagnosis and treatment. In addition, a lung and oral microbial biobank from lung cancer patients was established, which represents a useful resource for studies of host-microbe interactions.