Detection and analysis of lung microbiota in mice with lung cancer lacking the NLRP3 gene

To explore whether the lung microbiota have changed in the process of NLRP3 inflammasome promoting cancer, we constructed a murine lung cancer model using tracheal instillation of benzo(a)pyrene and an equal volume of tricaprylin, and characterized lung microbiota in bronchoalveolar lavage fluid from 24 SPF wild-type and NLRP3 gene knockout (NLRP3-/-) C57BL/6 mice. 16SrDNA sequencing was used to analyze the changes in the microbiota. The wild-type and the NLRP3-/- lung cancer group had sta-tistically significant differences in tumor formation rate, tumor number, and tumor size. At the phylum and the genus level, the relative abundance of Proteobacteria and Sphingomonas were the highest in each group respectively. Simpson (P = 0.002) and Shannon (P = 0.008) indexes showed that the diversity of microbiota in the lung cancer group was lower than that in the control group under the NLRP3-/- background. According to the ANOSIM and MRPP analysis, there was a difference between the NLRP3-/- lung cancer group and the NLRP3-/- control group (P < 0.05). The knockout of the NLRP3 gene caused changes in the lung microbiota of mice. There may be a regulatory relationship between the NLRP3 inflammasome and the lung microbiota, which affects the occurrence and development of lung cancer. (c) 2022 Elsevier Inc. All rights reserved.

Automated summary

By constructing a mouse lung cancer model and analyzing the lung microbiota in bronchoalveolar lavage fluid, we found that the NLRP3 inflammasome may have an impact on the lung microbiota during the process of lung cancer. Comparing the wild-type and NLRP3 gene knockout groups, significant differences were observed in tumor formation rate, tumor number, and tumor size. The relative abundance of Proteobacteria and Sphingomonas was the highest at the phylum and genus level, respectively. The knockout of the NLRP3 gene caused changes in the lung microbiota, suggesting a regulatory relationship between the NLRP3 inflammasome and lung microbiota in lung cancer development.