Association of gut microbiome with lung cancer in non-smoking women

Objective To investigate the association of alterations in gut microbiota with the risk of lung cancer in non-smoking women, and provide an evidence for the prevention and control of lung cancer in non-smoking women.

Methods A hospital-based multicenter case-control study was conducted. The 16S rRNA sequencing technique was used for sequencing of stool samples collected from 192 subjects, who were divided into lung-cancer case group with 92 subjects and control group with 100 subjects, and the diversity cloud analysis platform was used to analyze the features of gut microbiota in lung cancer patients. The LASSO regression analysis and the logistic regression analysis were used to investigate the association of the weighted scores of distinct gut microbiota with the risk of lung cancer in non-smoking women.

Results There were significant differences between the case group and the control group in the abundance (Wilcoxon test, P < 0.05) and β diversity (ANOSIM, P=0.01) of gut microbiota. The LEfSe analysis identified 22 differentially expressed bacterial genera between the case group and the control group, among which 11 genera including Bacteroides, Parabacteroides, Lachnoclostridium, Clostridium innocuum group, and Romboutsia were the characteristic bacterial genera in the case group, while 11 genera including Clostridium sensu stricto 1, Agathobacter, Dorea, Collinsella, and UCG-002 were the characteristic bacterial genera in the control group. The LASSO and logistic regression analyses showed that the scores of the differentially expressed flora were positively associated with the risk of lung cancer (AOR=2.22, 95% confidence interval: 1.63-3.02). In addition, living environment (living in basement or on the first floor for a long time) and frequency of intake of pickles, meat, and yogurt were also associated with the onset of lung cancer in non-smoking women, among which living in basement or on the first floor for a long time and high frequency of intake of pickles and meat were the risk factors for lung cancer, while high frequency of intake of yogurt was a protective factor against lung cancer.

Conclusion There are some differences in the structure of gut microbiota between lung cancer patients and non-lung cancer controls, and the change in intestinal microecology may be a risk factor for increasing the risk of lung cancer in non-smoking women.