TY - JOUR T1 - Interleukin-8 Expression Is Regulated by Histone Deacetylases through the Nuclear Factor-κB Pathway in Breast Cancer JF - Molecular Pharmacology JO - Mol Pharmacol SP - 1359 LP - 1366 DO - 10.1124/mol.108.047332 VL - 74 IS - 5 AU - Carine Chavey AU - Marcus Mühlbauer AU - Carine Bossard AU - Ariane Freund AU - Sébastien Durand AU - Christian Jorgensen AU - Christian Jobin AU - Gwendal Lazennec Y1 - 2008/11/01 UR - http://molpharm.aspetjournals.org/content/74/5/1359.abstract N2 - We have reported recently that the chemokine interleukin 8 (IL-8)/CXCL8 was overexpressed in invasive estrogen receptor (ERα)-negative breast cancer cells compared with ERα-positive breast cancer cells. We now demonstrate that histone deacetylases (HDACs) play an essential role in the regulation of IL-8 gene expression in ERα-positive MCF-7 breast cancer cells. Treatment of MCF-7 cells with the HDAC inhibitor trichostatin A (TSA) led to a strong up-regulation of IL-8 protein and RNA levels in MCF-7 cells. The up-regulation of IL-8 in MCF-7 cells was time- and concentration-dependent. Moreover, run-on and transfection experiments demonstrated that IL-8 induction by HDAC inhibitors was transcriptional and involved mainly the nuclear factor-κB (NF-κB) site of the IL-8 promoter. These observations are corroborated by an up-regulation of NF-κB activity in MCF-7 cells in the presence of TSA. In addition, blocking NF-κB pathway by adenoviral delivery of a dominant-negative IκBorIκB kinase complex 2 (IKK2) mutant abolished IL-8 gene induction by histone deacetylase inhibitors. HDAC inhibitors triggered IKK phosphorylation and up-regulated p65 nuclear translocation, although they decreased the protein levels of IκBα, which accounts for NF-κB activation. TSA increased binding of acetylated histone 3 to the IL-8 gene promoter. In summary, our results demonstrate that NF-κB pathway repression by HDAC is responsible for the low expression of IL-8 in ERα-positive breast cancer cells. The American Society for Pharmacology and Experimental Therapeutics ER -