Talazoparib arrests the cell cycle of lymphoma cells at G2/M. (A) Dose-response cell-viability curves at 24 hours for MBL2 and MDA-MB-436. (B) A volcano plot showing changes in transcriptome associated with the effect of talazoparib at IC₂₅ on the survival properties of MBL2 cells identified by RNA sequencing. (C) The transcriptional changes in the apoptosis pathway in MBL2 cells treated with IC₂₅ of talazoparib. (D) The transcriptional changes in the cell cycle pathway in MBL2 cells treated with IC₂₅ of talazoparib. (E) Cell cycle assessment after treatment of MBL2 cells with IC₂₅ of talazoparib. Click-iT EdU with FxCycle Violet Ready Assay. Representative flow cytometry. (F) The differences between the phases of cell cycle of cells treated with IC₂₅ of talazoparib and controls. ****P < .0001. (G) Hoechst 33258 fluorescent staining to show DNA breakage in MBL2 after exposure to talazoparib. Representative images, confocal macroscopy (original magnification, ×100). (H) An outline of the murine experiment. (I) The measurement of the thickness of the orthotopic tumors 21 days after treatment with talazoparib; n = 5 mice per group. ***P < .001 (J) The measurement of the diameter of the regional lymph nodes 21 days after treatment with talazoparib; n = 5 mice per group. *P < .05 (K) Representative images of regional lymph nodes treated with PBS or talazoparib.