To investigate the effect of canagliflozin on liver cancer cells and its regulatory mechanism.

The effects of canagliflozin on the proliferation of liver cancer cell HepG2, Huh7 and HCCM were detected by cell clone formation assay and CCK-8 assay. Flow cytometry was used to measure changes in reactive oxygen species (ROS) levels, both intracellular and mitochondrial ROS levels, as well as alterations in mitochondrial membrane potential. Western blot was employed to assess the expression of proteins related with proliferation and cGAS-STING pathway. Mitochondrial DNA (mtDNA) release and inflammatory factor mRNA expression level were detected by RT-qPCR.

Compared with human normal liver cell MIHA, the inhibitory effect of canagliflozin on HepG2 cell proliferation was more significant (P<0.05，semi-inhibitory concentrations were >40 μmol·L^-1 and 15 μmol·L^-1, respectively). Compared with the control group, the clone number of liver cancer cells and the expression of proliferation-related proteins in the canagliflozin group were decreased in a concentration dependent manner (P<0.05). Additionally, the intracellular and mitochondrial ROS levels were increased, the mitochondrial membrane potential was decreased, and the cytoplasmic mtDNA release level, cGAS-STING pathway-related protein expression and pro-inflammatory factor mRNA levels were increased (all P<0.05). Compared with the canagliflozin group, the intracellular and mitochondrial ROS levels, cytoplasmic mtDNA release levels, cGAS-STING pathway-related protein expression and pro-inflammatory factor mRNA levels in the N-acetyl-L-cysteine (NAC) +canagliflozin group were decreased (all P<0.05). Compared with the canagliflozin group, the proliferation activity and the expression of proliferation-related proteins in the cGAS inhibitor RU.521 + canagliflozin group were significantly increased (all P<0.05).

Canagliflozin induces oxidative stress in liver cancer cells, leading to the accumulation of ROS within cells and mitochondria, impairment of mitochondrial function, leakage of mtDNA into the cytoplasm, activation of the cGAS-STING pathway, and subsequent release of intracellular pro-inflammatory factors. These processes collectively contribute to the modulation of liver cancer cells proliferation.