Epigenetic CpG Demethylation of the Promoter and Reactivation of the Expression of Neurog1 by Curcumin in Prostate LNCaP Cells
Journal Title: The AAPS Journal - Year 2011, Vol 13, Issue 4
Abstract
Curcumin (CUR), a major bioactive polyphenolic component from turmeric curry, Curcuma longa, has been shown to be a potent anti-cancer phytochemical with well-established anti-inflammatory and anti-oxidative stress effects. Chromatin remodeling-related epigenetic regulation has emerged as an important mechanism of carcinogenesis, chemoprevention, and chemotherapy. CUR has been found to inhibit histone acetyltransferase activity, and it was also postulated to be a potential DNA methyltransferase (DNMT) and histone deacetylase (HDAC) inhibitor. In this study, we show that when human prostate LNCaP cells were treated with CUR, it led to demethylation of the first 14 CpG sites of the CpG island of the Neurog1 gene and restored the expression of this cancer-related CpG-methylation epigenome marker gene. At the protein level, CUR treatment had limited effects on the expression of epigenetic modifying proteins MBD2, MeCP2, DNMT1, and DNMT3a. Using ChIP assay, CUR decreased MeCP2 binding to the promoter of Neurog1 dramatically. CUR treatment showed different effects on the protein expression of HDACs, increasing the expression of HDAC1, 4, 5, and 8 but decreasing HDAC3. However, the total HDAC activity was decreased upon CUR treatment. Further analysis of the tri-methylation of histone 3 at lysine 27 (H3K27me3) showed that CUR decreased the enrichment of H3K27me3 at the Neurog1 promoter region as well as at the global level. Taken together, our present study provides evidence on the CpG demethylation ability of CUR on Neurog1 while activating its expression, suggesting a potential epigenetic modifying role for this phytochemical compound in human prostate cancer cells.
Authors and Affiliations
Limin Shu, Tin Oo Khor, Jong-Hun Lee, Sarandeep S. S. Boyanapalli, Ying Huang, Tien-Yuan Wu, Constance L. -L. Saw, Ka-Lung Cheung, Ah-Ng Tony Kong
Effect of PEG Surface Conformation on Anticancer Activity and Blood Circulation of Nanoemulsions Loaded with Tocotrienol-Rich Fraction of Palm Oil
Tocotrienol-rich fraction of palm oil, which contains the isomers of vitamin E, was shown to possess potent anticancer activity against mammary adenocarcinoma cell lines. Its clinical use, however, is limited by poor ora...
Novel Endogenous Glycan Therapy for Retinal Diseases: Safety, In Vitro Stability, Ocular Pharmacokinetic Modeling, and Biodistribution
The online version of this article (doi:10.1208/s12248-014-9563-1) contains supplementary material, which is available to authorized users.
Pharmacokinetic Evaluation of Intranasally Administered Vinyl Polymer-Coated Lorazepam Microparticles in Rabbits
The intranasal (IN) administration of lorazepam is desirable in order to maximize speed of onset and minimise carry-over sedation; however, this benzodiazepine is prone to chemical hydrolysis and poor airway retention, a...
Learning from the Viral Journey: How to Enter Cells and How to Overcome Intracellular Barriers to Reach the Nucleus
Viruses deliver their genome into host cells where they subsequently replicate and multiply. A variety of relevant strategies have evolved by which viruses gain intracellular access and utilize cellular machinery for the...
Aerosol delivery of muramyl dipeptide to rodent lungs
Tuberculosis is the single most serious infectious disease worldwide. The respiratory tract is the primary site of infection by Mycobacterium tuberculosis (MTB). A number of immunogenic components of the cell wall of MTB...