The PARP1 Inhibitor Niraparib Represses DNA Damage Repair and Synergizes with Temozolomide for Antimyeloma Effects

Figure 1

Nira induces synergistic cytotoxicity with TMZ in MM cell lines. (a) RPMI8226 and (b) NCI-H929 cells were exposed to increased Nira amounts for 48 h, before CCK-8 assay analysis of cell viability. (c) D MM cells were incubated for 48 h with increasing doses of TMZ and Nira (3 μM), either alone or in combination, followed by the CCK-8 assay. (e, f) MM cells were administered TMZ and/or Nira for 48 h (RPMI8226 cells, 30 μM and 3 μM, respectively, and NCI-H929 cells, 20 μM and 3 μM, respectively), followed by the CCK-8 assay. (g, h) Fa–CI plots according to the Chou–Talalay equation, generated by CompuSyn v1.0. Round symbol indicates CI (combination index) for a given Fa (fraction affected) at each dose. , , and versus control group; ^#, ^##, and ^### versus TMZ group; ⁺⁺⁺ versus Nira group. TMZ: temozolomide; Nira: niraparib.

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