Reactivating aberrantly hypermethylated p15 gene in leukemic T cells by a phenylhexyl isothiocyanate mediated inter-active mechanism on DNA and chromatin
نویسندگان
چکیده
BACKGROUND We have previously demonstrated that phenylhexyl isothiocyanate (PHI), a synthetic isothiocyanate, inhibits histone deacetylases and remodels chromatins to induce growth arrest in HL-60 myeloid leukemia cells in a concentration-dependent manner. METHODS To investigate the effect of PHI, a novel histone deacetylases inhibitor (HDACi), on demethylation and activation of transcription of p15 in acute lymphoid leukemia cell line Molt-4, and to further decipher the potential mechanism of demethylation, DNA sequencing and modified methylation specific PCR (MSP) were used to screen p15-M and p15-U mRNA after Molt-4 cells were treated with PHI, 5-Aza and TSA. DNA methyltransferase 1 (DNMT1), 3A (DNMT3A), 3B (DNMT3B) and p15 mRNA were measured by RT-PCR. P15 protein, acetylated histone H3 and histone H4 were detected by Western Blot. RESULTS The gene p15 in Molt-4 cells was hypermethylated and inactive. Hypermethylation of gene p15 was attenuated and p15 gene was activated de novo after 5 days exposure to PHI in a concentration-dependent manner. DNMT1 and DNMT3B were inhibited by PHI (P < 0.05). Alteration of DNMT3A was not significant at those concentrations. Acetylated histone H3 and histone H4 were accumulated markedly after exposure to PHI. CONCLUSION PHI could induce both DNA demethylation and acetylated H3 and H4 accumulation in Molt-4 cells. Hypermethylation of gene p15 was reversed and p15 transcription could be reactivated de novo by PHI.
منابع مشابه
Gene Expression and Promoter Methylation Status of VHL, Runx-3, E-cadherin, P15 and P16 Genes During EPO-Mediated Erythroid Differentiation of CD34+ Hematopoietic Stem Cells
Background: VHL (von Hippel-Lindau), Runx-3 (Runt-related transcription factor 3), E-cadherin (Epithelial cadherin), P15 (INK4a, cyclin dependent kinase inhibitor), and P16 (INK4b) genes are essential in hematopoiesis. The aim of this study was to explore the correlation between gene expression and promoter methylation in CD34+ stem cells before and after differentiation to erythroid lineage. M...
متن کاملSilenced tumor suppressor genes reactivated by DNA demethylation do not return to a fully euchromatic chromatin state.
Histone H3 lysine 9 (H3K9) and lysine 27 (H3K27) trimethylation are properties of stably silenced heterochromatin whereas H3K9 dimethylation (H3K9me2) is important for euchromatic gene repression. In colorectal cancer cells, all of these marks, as well as the key enzymes which establish them, surround the hMLH1 promoter when it is DNA hypermethylated and aberrantly silenced, but are absent when...
متن کاملPhenylhexyl isothiocyanate inhibits histone deacetylases and remodels chromatins to induce growth arrest in human leukemia cells.
Natural isothiocyanates, present in cruciferous vegetables and synthetic phenylhexyl isothiocyanate (PHI) are chemopreventive agents which act by blocking the initiation of carcinogen-induced tumors in rodents. We have demonstrated that isothiocyanates are also growth regulators, inhibiting cell cycle cdk activity and up-regulating inhibitor p21WAF1 (p21) in cancer cells. The up-stream mechanis...
متن کاملIdentification of aberrantly methylated genes in association with adult T-cell leukemia.
In this study, we identified 53 aberrantly hypermethylated DNA sequences in adult T-cell leukemia (ATL) cells using methylated CpG island amplification/representational difference analysis method. We also observed a proportionate increase in the methylation density of these regions with disease progression. Seven genes, which were expressed in normal T cells, but suppressed in ATL cells, were i...
متن کاملGene Expression and Promoter Methylation Status of VHL, Runx-3, E-cadherin, P15 and P16 Genes During EPO-Mediated Erythroid Differentiation of CD34+ Hematopoietic Stem Cells
Background: VHL (von Hippel-Lindau), Runx-3 (Runt-related transcription factor 3), E-cadherin (Epithelial cadherin), P15 (INK4a, cyclin dependent kinase inhibitor), and P16 (INK4b) genes are essential in hematopoiesis. The aim of this study was to explore the correlation between gene expression and promoter methylation in CD34+ stem cells before and after differentiation to erythroid lineage. ...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره 3 شماره
صفحات -
تاریخ انتشار 2010