Zhidai Decoction Inhibits Cervical Cancer through Regulation of Vaginal Microbiota

Cervical cancer is one of the top lethal malignancies among women worldwide. The current treatment methods have so many drawbacks that new treatment methods need to be developed. Zhidai Decoction (ZDD) is an effective traditional Chinese herbal formulation for gynecological diseases. Its main effect is controlling abnormal leucorrhea which is a typical early clinical manifestation of cervical cancer. However, how ZDD directly affects cervical cancer has not been addressed. In this study, we established a mouse cervical cancer U14 cell subcutaneous transplantation tumor model and took an early intervention with ZDD to evaluate the antitumor effect of ZDD. In addition, we also investigated the regulatory effects of ZDD on the vaginal microbiota using 16S rRNA analysis in this study. Our results showed that ZDD can significantly improve systemic symptoms and reduce vaginal secretions of tumor-bearing mice. Compared with the CCM group (the cervical cancer model group), in the ZDD-treated group, the tumor inhibitory rate was 37.90%, the average daily food intake of mice was increased to 5.27 ± 0.74 g (P < 0.05), and the survival time was obviously prolonged to 21 days (P < 0.05). Analysis of the sequencing results of 16S rRNA showed that the main microbial genera of the CCM group were Pasteurella (27.20%) and Helicobacter (18.50%), while those in the ZDD group were Staphylococcus (13.22%) and Lactobacillus (4.68%). It revealed that ZDD has the effect of regulating the vaginal microbiota of cervical cancer, especially in increasing the relative abundance of Lactobacillus and Staphylococcus and decreasing the relative abundance of Pasteurella and Helicobacter. The analysis also showed that ZDD could adjust microbiota structure, species abundance, and community compositions of vaginal microbiota. In conclusion, ZDD displayed inhibitory effect on cervical cancer, and it might be based on restoring the balance of vaginal microbiota. Furthermore, our conclusion supports the promotion of ZDD in the early treatment of cervical cancer.