Piperlongumine Inhibits NF-κB Activity and Attenuates Aggressive Growth Characteristics of Prostate Cancer Cells

BACKGROUNDElevated NF-B activity has been previously demonstrated in prostate cancer cell lines as hormone-independent or metastatic characteristics develop. We look at the effects of piperlongumine (PL), a biologically active alkaloid/amide present in piper longum plant, on the NF-B pathway in androgen-independent prostate cancer cells. METHODSNF-B activity was evaluated using Luciferase reporter assays and Western blot analysis of p50 and p65 nuclear translocation. IL-6, IL-8, and MMP-9 levels were assessed using ELISA. Cellular adhesion and invasiveness properties of prostate cancer cells treated with PL were also assessed. RESULTSNF-B DNA-binding activity was directly down-regulated with increasing concentrations of PL, along with decreased nuclear translocation of p50 and p65 subunits. Expression of IL-6, IL-8, MMP-9, and ICAM-1 was attenuated, and a decrease of cell-to-matrix adhesion and invasiveness properties of prostate cancer cells were observed. CONCLUSIONSPL-mediated inhibition of NF-B activity decreases aggressive growth characteristics of prostate cancer cells in vitro. Prostate 74:177-186, 2014. (c) 2013 Wiley Periodicals, Inc.