IC50: 20 and 10 μM for the growth of PANC-1 and U87 tumor cells, respectively

Farnesyl thiosalicylic acid amide (FTS-A), an farnesyl thiosalicylic acid derivative, inhibits tumor growth.

Farnesylthiosalicylic acid (FTS, Salirasib), a Ras inhibitor, can interfer with Ras membrane interactions that are crucial for Ras-dependent transformation.

In vitro: Previous study examined the effects of the FTS-A and its two analogs (FTS-MA and FTS-DMA) on panc-1 and U87 cells and the results showed that all three FTS-amides caused a dose-dependent decrease in cell number of both cell lines exhibiting similar potencies. Cell death was observed at concentrations higher than 50 μM. The IC50s recorded in both cell lines were at the range of 10-20 μM. FTS-A, FTS-MA, and FTS-DMA caused a clear decrease in the levels of K-Ras-GTP in Panc-1 cells and in U87 cells. Reduction in the level of N-Ras-GTP was observed only in U87 cells and no effect on H-Ras-GTP was observed in either cell line [1].

In vivo: The effect of FTS-A on brain tumor growth was examined using a nude mouse model with human glioblastoma U87 cells intracranially implanted into the striatum area. FTS-A at 100 mg/kg was administered orally twice daily. Results showed that the increase in tumor volume recorded over time in the FTS-A treated mouse was significantly lower than that recorded in the control mouse. Moreover, it was found that more contrast agent molecules accumulated in the control mice as compared to the FTS-A treated mice. In addition, this study did not see any inflammatory response in the brains of the controls or in the brains of FTS-A-treated mice [1].

Clinical trial: So far, no clinical study has been conducted.

Reference:
[1] Goldberg, L. ,Haklai, R.,Bauer, V., et al. New derivatives of farnesylthiosalicylic acid (salirasib) for cancer treatment: Farnesylthiosalicylamide inhibits tumor growth in nude mice models. Journal of Medicinal Chemistry 52, 197-205 (2009).