Abstract 146P
Background
At present, the samples for studying lung microbiota are mainly derived from sputum, bronchoscopic samples, bronchoalveolar lavage and tumor tissues. several taxa of bacteria may be enriched in lung cancer tissue, however there are relatively few reports on the microbes in tumor tissues. In most reports, the alpha diversity of bacteria in lung cancer tissues is lower than that in healthy lung tissues, but the association between microbiome in lung tumor tissues and lymph node metastasis in lung cancer was not reported.
Methods
We performed 16S rRNA gene sequencing of a total of 40 primary tumor tissue samples from 12 lung adenocarcinoma patients with lymph node metastasis (metastasis cohort) and 28 lung adenocarcinoma patients without lymph node metastasis (non-metastasis cohort). We utilized the LEfSe method to compare relative abundances of all bacterial taxa between non-metastasis cohort and metastasis cohort. For alpha diversity, we calculated the Shannon index of the 97% identity OTUs using alph_diversity.py. Beta diversity measurements were calculated using beta_diversity.py to determine NMDS (Non-Metric Multi-Dimensional Scaling), PCoA (Principal Co-ordinates Analysis), PCA (Principal Component Analysis) and UPGMA (Unweighted Pair-group Method with Arithmetic Mean).
Results
Alpha diversity was higher in non-metastasis cohort than that in metastasis cohort, but no significance (observed species P = 0.08, and Shannon index P = 0.03). Beta diversity was higher in non-metastasis cohort than that in metastasis cohort significantly (weighted unifrac p<0.01). Compared to non-metastasis cohort, the relative abundance rate of familie verrucomicrobia (metastasis cohort 0.056 and non-metastasis cohort 0.022, p<0.05) was greater in metastasis cohort, of which Akkermansia muciniphila (metastasis cohort 0.057 and non-metastasis cohort 0.023, p<0.05) was significantly different between the two cohorts.
Conclusions
We demonstrated, for the first time, a potential relationship between the microbe Akkermansia muciniphila in lung adenocarcinoma tissues and lymph node metastasis in lung adenocarcinoma, which needs to be confirmed in a larger study.
Clinical trial identification
Editorial acknowledgement
Legal entity responsible for the study
The First Affiliated Hospital of Kunming Medical University.
Funding
Has not received any funding.
Disclosure
All authors have declared no conflicts of interest.