LNS-8801–induced cytotoxicity is mediated by ROS and synergizes with current clinical treatments. (A) ROS levels were quantified by flow cytometry in ALCL (Mac-2A, TLBR-2, DEL, and FE-PD), DLBCL (OCI-Ly10 and SU-DHL-6), and MM (LP-1) cell lines treated with DMSO or LNS-8801 (400 nM) for 48 hours, as shown by the mean fluorescence intensity (MFI) of DCF, normalized to the DMSO control. Notably, the LNS-8801–resistant cell lines FE-PD and LP-1 did not exhibit increased ROS levels upon treatment. (B-C) ALCL (Mac-2A) and DLBCL (OCI-Ly10) cell lines were treated with DMSO, LNS-8801 (400 nM), α-tocopherol (300 μM), or a combination of the compounds. (B) ROS levels were quantified by flow cytometry after 48 hours, and (C) cell viability was determined as indicated after 72 hours, normalized to the solvent control. (D) Mitochondrial membrane potential (ΔΨm) was detected by JC-1 probes and shown as the relative MFI of JC-1 monomers (green fluorescence) in the indicated cell lines treated with LNS-8801 (400 nM) for 48 hours, normalized to the DMSO control. (E-F) Heat maps of the dose-response matrices showing enhanced cytotoxicity in ALCL (Mac-2A and JB6) and DLBCL (OCI-Ly10 and BJAB) cell lines treated with combinations of LNS-8801 and brentuximab vedotin or polatuzumab vedotin, respectively. The strength of inhibition is depicted according to the color scale. Data are presented as mean ± standard deviation of at least 3 independent experiments. ∗P < .05, ∗∗P < .01, ∗∗∗P < .001, and ∗∗∗∗P < .0001. DCF, dichlorofluorescein; MM, multiple myeloma; n.s., not significant.