TG2 activity is correlated with NF-κB expression in MCL. (A) SP-53 and Jeko-1 cells were treated with A23187 (2μM for 24 hours) to activate TG2, and TG2 enzymatic activity was measured using TG2-CovTest TG2-specific colorimetric assay kit (Novus Biologicals) with cell extracts from untreated and treated SP-53 and Jeko-1 cells. Changes in TG2 enzymatic levels before and after treatment with A23187 were measured. The colorimetric values (optical density, 450 nm) in untreated samples were subtracted from the values measured in treated samples. Results are shown as the means ± SD. Treatment with A23187 clearly induced the activation of TG2. (B) Nuclear extracts from SP-53 and Jeko-1 cells that were untreated or treated with A23187 (2μM for 24 hours) were analyzed using ELISA assays to evaluate p50 and p65 DNA-binding activities. Changes in p50 and p65 DNA-binding activity levels before and after treatment with A23187 were measured. The colorimetric values (optical density, 450 nm) in untreated samples were subtracted from the values measured in treated samples. Results are shown as the means ± SD. TG2 activation increased NF-κB DNA-binding activities in MCL cells. (C) SP-53 and Jeko-1 cells were treated with MDC (50μM for 24 hours) or BPA (1mM for 24 hours) for TG2 inhibition. TG2 enzymatic activities were measured using the TG2-specific colorimetric assay with cell extracts from untreated and treated SP-53 and Jeko-1 cells. Changes in TG2 enzymatic levels before and after treatment with MDC or BPA were measured. The colorimetric values in untreated samples were subtracted from those measured in treated samples. Results are shown as the means ± SD. Treatment with the TG2-specific inhibitors MDC and BPA inhibited TG2 expression. (D) Nuclear extracts from SP-53 and Jeko-1 cells with or without the TG2-specific inhibitors MDC (50μM for 24 hours) and BPA (1mM for 24 hours) were subjected to ELISA assays to evaluate p50 and p65 DNA-binding activities. Changes in p50 and p65 DNA-binding activity levels before and after treatment with MDC or BPA were measured. The colorimetric values in untreated samples were subtracted from those measured in treated samples. Results are shown as the means ± SD. TG2 inhibition suppressed NF-κB expression in MCL cells.