TAC-101 inhibits intrahepatic metastasis of orthotopically implanted murine hepatocellular carcinoma.

The anti-metastatic effect of 4-[3,5-bis(trimethylsilyl)benzamido]benzoic acid (TAC-101) was investigated using our established intrahepatic metastasis model. Orthotopic implantation of a fragment of CBO140C12 hepatoma into the liver resulted in the formation of a solitary tumor nodule and its intrahepatic metastasis. Daily oral administration of TAC-101 at a dose of 8 mg/kg resulted in a significant inhibition of intrahepatic metastasis, but did not affect the growth of the tumor at the implanted site. The down-regulation of transcriptional anti-activator protein-1 (AP-1) activity by TAC-101 paralleled the inhibition of cell invasion and migration through the repression of expression of the mRNAs for urokinase-type plasminogen activator (u-PA) and its receptor (u-PAR). These findings suggest that TAC-101 may improve therapeutic efficacy for liver cancer patients to prevent intrahepatic metastasis.