Effects of Respiratory Prevotella Melaninogenica on the Growth of Lewis Transplanted Tumor in Mice
Objective To investigate the effect of Prevotella melaninogenica(PM)colonized in lung cancer patients on the growth of Lewis transplanted tumor in mice.Methods A total of 40 6-week-old C57BL/6J female mice were purchased,30 were randomly selected to construct Lewis transplanted tumor model,and 10 were used as control group.At 14 days,the model group of mice were randomly divided into PBS group,PM1 group and PM2 group,and PBS or PM bacterial solution was injected into the tumor peri-tumor twice a week.The growth of mouse tumor cells was observed.Alveolar lavage fluid was collected from mice,and the microbial composition and microbial diversity were analyzed by 16S rRNA amplicon sequencing.Results The volume and weight of tumor in PM1 and PM2 groups were higher than those in PBS group,and the difference was statistically significant(P<0.05).Compared with the control group and PBS group,the abundance of microorganisms in pulmonary alveolar lavage fluid of mice in PM group was increased,the diversity of Alpha was increased,and the diversity of Bete was decreased.Conclusion The increase of local PM in mouse tumor significantly promoted the growth of Lewis transplanted tumor,and affected the microflora balance in the lower respiratory tract of mice.