<i>P</i>. <i>mirabilis</i> suppressed spontaneous pulmonary metastases <i>in vivo</i>.

<p>Bacterial treatment inhibited tumor spontaneous pulmonary metastases by observing fresh lung tissues (A) at the end of the experiment. (B) Quantitative statistics of metastatic foci showed significant differences between <i>P</i>. <i>mirabilis</i> treatment group and PBS control group (n = 6) (p < 0.05). (C) Quantitative statistics showed lung weight of mice in the control group was significantly higher than those in the <i>P</i>. <i>mirabilis</i> treatment group (p < 0.05). (D) Those results were further confirmed by analyzing H&E stained sections. Data were expressed as the mean ± SD.