Fig. 4

Metformin inhibits the growth of SiHa cell-derived cervical cancer xenografts in a nude mouse model. a Inhibition of tumor growth by metformin; b Western blotting showing upregulation of MICA and p53 protein expression and inhibition of PI3K (p110ɑ), phospho-PI3Kp55 (Tyr199), and phospho-Akt (ser473) protein expression in xenograft tissues by metformin; c Schematic diagram showing the proposed mechanism of metformin, which upregulates MICA expression through the PI3K/Akt pathway and enhances the killing effects of NK cells on tumor cells, thereby improving the recognition of cervical cancer cells by NK cells and disrupting tumor immune escape. In addition, metformin activates p53 expression through the PI3K/Akt pathway to inhibit tumor cell proliferation. The data are presented as mean ± standard deviation, n = 3. *P < 0.05, and **P < 0.01, compared to the 0 μM metformin treatment group