Etoposide phosphate is a phosphate salt of Etoposide, which binds to the enzyme topoisomerase II, then induces double-strand DNA breaks and inhibits DNA repair, leading to decreased DNA synthesis and tumor cell proliferation.
Ki23057 is a a FGFR2 inhibitor, which enhances the chemosensitivity of drug-resistant gastric cancer cell lines when used in combination with chemotherapeutic drugs. Ki23057 might be therapeutically promising for treating drug-resistant gastric cancer cells, especially when used in combination with SN38, PTX, or VP16. The apoptosis process might be the main mechanism underlying the synergistic effect of these combinations. The ERCC1 and p53 genes may play an integral role in the synergism between Ki23057 and chemotherapeutic agents in drug-resistant cell lines. (source: Cancer Lett. 2011 Aug 1;307(1):47-52).