RAD51 potentiates synergistic effects of chemotherapy with PCI-24781 and cis-diamminedichloroplatinum on gastric cancer

Figure 1 PCI-24781 suppressed gastric cancer cell growth and synergized with the effect of cis-diamminedichloroplatinum. The gastric cell lines HGC27 and AGS were plated at densities of 2 × 10³ cells per well in 96-well plates and were subjected to cell growth assays. The cells were incubated with various concentrations of PCI-24781 and/or cis-diamminedichloroplatinum (CDDP) for 48 h, and the inhibition ratio was determined (IC₅₀). Cell growth assays showed the significant cell growth inhibition of the GC cells in response to PCI-24781 (A, B) and CDDP (C, D) treatment. Isobologram analysis was used to evaluate the synergistic effect. The data point (IC₅₀) from the combination treatment is shown on the left side of the curve and was generated by IC₅₀ of the two drugs; this suggests that the combination treatment (concentration constant ratio PCI-24781:CDDP = 1:10) as synergistic (E, F).