Anticancer effect of 4-[3,5-bis(trimethylsilyl)benzamido] benzoic acid (TAC-101) against A549 non-small cell lung cancer cell line is related to its anti-invasive activity.

We examined the effects of TAC-101 on the invasion and metastasis of human non-small cell lung cancer (NSCLC) cell lines. TAC-101 showed an ability to inhibit in vitro invasiveness of NSCLC at a non-cytotoxic concentration range of 3-10 microM; such concentration levels were easily achievable following oral administration of therapeutically effective doses. The inhibition of cell invasion at 10 microM of TAC-101 accounted for 58-69% when compared with control cells. Oral administration of TAC-101 (4 mg/kg/day) to mice bearing lung implanted A549 lung cancer resulted in significant life-prolonging effect (T/C: 143%). More pronounced life-prolonging effect was observed in the experimental liver metastasis model of A549, where T/C of 215% was observed following administration at 4 mg/kg/day of TAC-101. However, TAC-101 did not show the direct anti-tumor effect against the established A549 tumor xenografts after subcutaneous implantation. These findings suggest that TAC-101 interferes with cell-to-cell interaction processes leading, for instance, to the inhibition of the invasion of NSCLC cells. Taking into account the pharmacological properties of TAC-101, it is expected that TAC-101 may be a suitable candidate drug for the treatment of lung cancer patients, especially those with a predictable metastasizing potential.