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Glycolytic metabolism influences global chromatin structure.

Liu XS, Little JB, Yuan ZM - Oncotarget (2015)

Bottom Line: But the interrelationship between tumor metabolism and chromatin architecture remain unclear.Using complementary methods including Micrococcal nuclease (MNase) digestion assay, electron microscope and immunofluorescence staining, we demonstrate that glycolysis inhibition by pharmacological and genetic approaches was associated with induction of compacted chromatin structure.This condensed chromatin status appeared to result chiefly from histone hypoacetylation as restoration of histone acetylation with an HDAC inhibitor reversed the compacted chromatin state.

View Article: PubMed Central - PubMed

Affiliation: Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, MA 02115, USA.

ABSTRACT
Metabolic rewiring, specifically elevated glycolytic metabolism is a hallmark of cancer. Global chromatin structure regulates gene expression, DNA repair, and also affects cancer progression. But the interrelationship between tumor metabolism and chromatin architecture remain unclear. Here we show that increased glycolysis in cancer cells promotes an open chromatin configuration. Using complementary methods including Micrococcal nuclease (MNase) digestion assay, electron microscope and immunofluorescence staining, we demonstrate that glycolysis inhibition by pharmacological and genetic approaches was associated with induction of compacted chromatin structure. This condensed chromatin status appeared to result chiefly from histone hypoacetylation as restoration of histone acetylation with an HDAC inhibitor reversed the compacted chromatin state. Interestingly, glycolysis inhibition-induced chromatin condensation impeded DNA repair efficiency leading to increased sensitivity of cancer cells to DNA damage drugs, which may represent a novel molecular mechanism that can be exploited for cancer therapy.

No MeSH data available.


Related in: MedlinePlus

Glycolytic metabolism stimulates open global chromatin structure(A) A549 cells treated with glycolysis inhibitor 2-DG or transfected with siRNA targeting key glycolysis enzymes HK1, PKM were digested with increasing concentration of Micrococcal nuclease (MNase). Genomic DNA was analyzed with agarose gel electrophoresis. (B) Immunofluorescent staining with heterochromatin marker HP1α and H3K9me3 antibody in A549 cells treated with control, 2-DG or transfected with siRNA targeting HK1, PKM. Scale bar is 5 μm. (C) A549 cells treated with 2-DG or transfected with siRNA targeting HK1, PKM were fixed and analyzed by transmission electron microscopy. Arrows indicate heterochromatic regions. Scale bar is 5 μm.
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Figure 1: Glycolytic metabolism stimulates open global chromatin structure(A) A549 cells treated with glycolysis inhibitor 2-DG or transfected with siRNA targeting key glycolysis enzymes HK1, PKM were digested with increasing concentration of Micrococcal nuclease (MNase). Genomic DNA was analyzed with agarose gel electrophoresis. (B) Immunofluorescent staining with heterochromatin marker HP1α and H3K9me3 antibody in A549 cells treated with control, 2-DG or transfected with siRNA targeting HK1, PKM. Scale bar is 5 μm. (C) A549 cells treated with 2-DG or transfected with siRNA targeting HK1, PKM were fixed and analyzed by transmission electron microscopy. Arrows indicate heterochromatic regions. Scale bar is 5 μm.

Mentions: Metabolic reprogramming is a hallmark of cancer, and cancer cells always show elevated glycolytic metabolism [7]. Tumor cells also show discrete changes in their nucleus structure [2]. We examined a potential contribution of tumor metabolism to the distinct chromatin architecture in tumor cells by inhibition of glycolysis. We performed the Micrococcal nuclease (MNase) digestion assay to monitor chromatin structural change in response to glycolysis inhibition. Treatment of human lung carcinoma cell line A549 with 2-Deoxy-D-glucose (2-DG) resulted in increased resistance to the digestion of MNase, indicative of more compact chromatin structure (Figure 1A). To corroborate the result obtained from 2-DG, we used siRNA to knock down the expression of HK1 and PKM, two rate limiting enzymes for glycolysis. Similar to the effect of 2-DG, reduced expression of HK1 and PKM (Supplemental Figure S1) was also associated with induction of MNase resistance in chromatin (Figure 1A). The results together indicate that inhibition of glycolysis in tumor cells caused a change of chromatin structure into a more condensed state.


Glycolytic metabolism influences global chromatin structure.

Liu XS, Little JB, Yuan ZM - Oncotarget (2015)

Glycolytic metabolism stimulates open global chromatin structure(A) A549 cells treated with glycolysis inhibitor 2-DG or transfected with siRNA targeting key glycolysis enzymes HK1, PKM were digested with increasing concentration of Micrococcal nuclease (MNase). Genomic DNA was analyzed with agarose gel electrophoresis. (B) Immunofluorescent staining with heterochromatin marker HP1α and H3K9me3 antibody in A549 cells treated with control, 2-DG or transfected with siRNA targeting HK1, PKM. Scale bar is 5 μm. (C) A549 cells treated with 2-DG or transfected with siRNA targeting HK1, PKM were fixed and analyzed by transmission electron microscopy. Arrows indicate heterochromatic regions. Scale bar is 5 μm.
© Copyright Policy - open-access
Related In: Results  -  Collection

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getmorefigures.php?uid=PMC4414184&req=5

Figure 1: Glycolytic metabolism stimulates open global chromatin structure(A) A549 cells treated with glycolysis inhibitor 2-DG or transfected with siRNA targeting key glycolysis enzymes HK1, PKM were digested with increasing concentration of Micrococcal nuclease (MNase). Genomic DNA was analyzed with agarose gel electrophoresis. (B) Immunofluorescent staining with heterochromatin marker HP1α and H3K9me3 antibody in A549 cells treated with control, 2-DG or transfected with siRNA targeting HK1, PKM. Scale bar is 5 μm. (C) A549 cells treated with 2-DG or transfected with siRNA targeting HK1, PKM were fixed and analyzed by transmission electron microscopy. Arrows indicate heterochromatic regions. Scale bar is 5 μm.
Mentions: Metabolic reprogramming is a hallmark of cancer, and cancer cells always show elevated glycolytic metabolism [7]. Tumor cells also show discrete changes in their nucleus structure [2]. We examined a potential contribution of tumor metabolism to the distinct chromatin architecture in tumor cells by inhibition of glycolysis. We performed the Micrococcal nuclease (MNase) digestion assay to monitor chromatin structural change in response to glycolysis inhibition. Treatment of human lung carcinoma cell line A549 with 2-Deoxy-D-glucose (2-DG) resulted in increased resistance to the digestion of MNase, indicative of more compact chromatin structure (Figure 1A). To corroborate the result obtained from 2-DG, we used siRNA to knock down the expression of HK1 and PKM, two rate limiting enzymes for glycolysis. Similar to the effect of 2-DG, reduced expression of HK1 and PKM (Supplemental Figure S1) was also associated with induction of MNase resistance in chromatin (Figure 1A). The results together indicate that inhibition of glycolysis in tumor cells caused a change of chromatin structure into a more condensed state.

Bottom Line: But the interrelationship between tumor metabolism and chromatin architecture remain unclear.Using complementary methods including Micrococcal nuclease (MNase) digestion assay, electron microscope and immunofluorescence staining, we demonstrate that glycolysis inhibition by pharmacological and genetic approaches was associated with induction of compacted chromatin structure.This condensed chromatin status appeared to result chiefly from histone hypoacetylation as restoration of histone acetylation with an HDAC inhibitor reversed the compacted chromatin state.

View Article: PubMed Central - PubMed

Affiliation: Department of Genetics and Complex Diseases, Harvard School of Public Health, Boston, MA 02115, USA.

ABSTRACT
Metabolic rewiring, specifically elevated glycolytic metabolism is a hallmark of cancer. Global chromatin structure regulates gene expression, DNA repair, and also affects cancer progression. But the interrelationship between tumor metabolism and chromatin architecture remain unclear. Here we show that increased glycolysis in cancer cells promotes an open chromatin configuration. Using complementary methods including Micrococcal nuclease (MNase) digestion assay, electron microscope and immunofluorescence staining, we demonstrate that glycolysis inhibition by pharmacological and genetic approaches was associated with induction of compacted chromatin structure. This condensed chromatin status appeared to result chiefly from histone hypoacetylation as restoration of histone acetylation with an HDAC inhibitor reversed the compacted chromatin state. Interestingly, glycolysis inhibition-induced chromatin condensation impeded DNA repair efficiency leading to increased sensitivity of cancer cells to DNA damage drugs, which may represent a novel molecular mechanism that can be exploited for cancer therapy.

No MeSH data available.


Related in: MedlinePlus