The Experts below are selected from a list of 120 Experts worldwide ranked by ideXlab platform
Conrad Wagner - One of the best experts on this subject based on the ideXlab platform.
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folate deficiency affects histone methylation
Medical Hypotheses, 2016Co-Authors: Benjamin A Garcia, Lioudmila V Loukachevitch, Zigmund Luka, Natarajan V Bhanu, Conrad WagnerAbstract:Formaldehyde is extremely toxic reacting with proteins to crosslinks peptide chains. Formaldehyde is a metabolic product in many enzymatic reactions and the question of how these enzymes are protected from the formaldehyde that is generated has largely remained unanswered. Early experiments from our laboratory showed that two liver mitochondrial enzymes, dimethylglycine Dehydrogenase (DMGDH) and Sarcosine Dehydrogenase (SDH) catalyze oxidative demethylation reactions (Sarcosine is a common name for monomethylglycine). The enzymatic products of these enzymes were the demethylated substrates and formaldehyde, produced from the removed methyl group. Both DMGDH and SDH contain FAD and both have tightly bound tetrahydrofolate (THF), a folate coenzyme. THF binds reversibly with formaldehyde to form 5,10-methylene-THF. At that time we showed that purified DMGDH, with tightly bound THF, reacted with formaldehyde generated during the reaction to form 5,10-methylene-THF. This effectively scavenged the formaldehyde to protect the enzyme. Recently, post-translational modifications on histone tails have been shown to be responsible for epigenetic regulation of gene expression. One of these modifications is methylation of lysine residues. The first enzyme discovered to accomplish demethylation of these modified histones was histone lysine demethylase (LSD1). LSD1 specifically removes methyl groups from di- and mono-methylated lysines at position 4 of histone 3. This enzyme contained tightly bound FAD and the products of the reaction were the demethylated lysine residue and formaldehyde. The mechanism of LSD1 demethylation is analogous to the mechanism previously postulated for DMGDH, i.e. oxidation of the N-methyl bond to the methylene imine followed by hydrolysis to generate formaldehyde. This suggested that THF might also be involved in the LSD1 reaction to scavenge the formaldehyde produced. Our hypotheses are that THF is bound to native LSD1 by analogy to DMGDH and SDH and that the bound THF serves to protect the FAD class of histone demethylases from the destructive effects of formaldehyde generation by formation of 5,10-methylene-THF. We present pilot data showing that decreased folate in livers as a result of dietary folate deficiency is associated with increased levels of methylated lysine 4 of histone 3. This can be a result of decreased LSD1 activity resulting from the decreased folate available to scavenge the formaldehyde produced at the active site caused by the folate deficiency. Because LSD1 can regulate gene expression this suggests that folate may play a more important role than simply serving as a carrier of one-carbon units and be a factor in other diseases associated with low folate.
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crystal structure of the histone lysine specific demethylase lsd1 complexed with tetrahydrofolate
Protein Science, 2014Co-Authors: Zigmund Luka, Svetlana Pakhomova, Lioudmila V Loukachevitch, Wade M Calcutt, Marcia E Newcomer, Conrad WagnerAbstract:An important epigenetic modification is the methylation/demethylation of histone lysine residues. The first histone demethylase to be discovered was a lysine-specific demethylase 1, LSD1, a flavin containing enzyme which carries out the demethylation of di- and monomethyllysine 4 in histone H3. The removed methyl groups are oxidized to formaldehyde. This reaction is similar to those performed by dimethylglycine Dehydrogenase and Sarcosine Dehydrogenase, in which protein-bound tetrahydrofolate (THF) was proposed to serve as an acceptor of the generated formaldehyde. We showed earlier that LSD1 binds THF with high affinity which suggests its possible participation in the histone demethylation reaction. In the cell, LSD1 interacts with co-repressor for repressor element 1 silencing transcription factor (CoREST). In order to elucidate the role of folate in the demethylating reaction we solved the crystal structure of the LSD1–CoREST–THF complex. In the complex, the folate-binding site is located in the active center in close proximity to flavin adenine dinucleotide. This position of the folate suggests that the bound THF accepts the formaldehyde generated in the course of histone demethylation to form 5,10-methylene-THF. We also show the formation of 5,10-methylene-THF during the course of the enzymatic reaction in the presence of THF by mass spectrometry. Production of this form of folate could act to prevent accumulation of potentially toxic formaldehyde in the cell. These studies suggest that folate may play a role in the epigenetic control of gene expression in addition to its traditional role in the transfer of one-carbon units in metabolism.
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histone demethylase lsd1 is a folate binding protein
Biochemistry, 2011Co-Authors: Zigmund Luka, Lioudmila V Loukachevitch, Frank R Moss, Darryl J Bornhop, Conrad WagnerAbstract:Methylation of lysine residues in histones has been known to serve a regulatory role in gene expression. Although enzymatic removal of the methyl groups was discovered as early as 1973, the enzymes responsible for their removal were isolated and their mechanism of action was described only recently. The first enzyme to show such activity was LSD1, a flavin-containing enzyme that removes the methyl groups from lysines 4 and 9 of histone 3 with the generation of formaldehyde from the methyl group. This reaction is similar to the previously described demethylation reactions conducted by the enzymes dimethylglycine Dehydrogenase and Sarcosine Dehydrogenase, in which protein-bound tetrahydrofolate serves as an accepter of the formaldehyde that is generated. We now show that nuclear extracts of HeLa cells contain LSD1 that is associated with folate. Using the method of back-scattering interferometry, we have measured the binding of various forms of folate to both full-length LSD1 and a truncated form of LSD1 in free solution. The 6R,S form of the natural pentaglutamate form of tetrahydrofolate bound with the highest affinity (K(d) = 2.8 μM) to full-length LSD1. The fact that folate participates in the enzymatic demethylation of histones provides an opportunity for this micronutrient to play a role in the epigenetic control of gene expression.
Zigmund Luka - One of the best experts on this subject based on the ideXlab platform.
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folate deficiency affects histone methylation
Medical Hypotheses, 2016Co-Authors: Benjamin A Garcia, Lioudmila V Loukachevitch, Zigmund Luka, Natarajan V Bhanu, Conrad WagnerAbstract:Formaldehyde is extremely toxic reacting with proteins to crosslinks peptide chains. Formaldehyde is a metabolic product in many enzymatic reactions and the question of how these enzymes are protected from the formaldehyde that is generated has largely remained unanswered. Early experiments from our laboratory showed that two liver mitochondrial enzymes, dimethylglycine Dehydrogenase (DMGDH) and Sarcosine Dehydrogenase (SDH) catalyze oxidative demethylation reactions (Sarcosine is a common name for monomethylglycine). The enzymatic products of these enzymes were the demethylated substrates and formaldehyde, produced from the removed methyl group. Both DMGDH and SDH contain FAD and both have tightly bound tetrahydrofolate (THF), a folate coenzyme. THF binds reversibly with formaldehyde to form 5,10-methylene-THF. At that time we showed that purified DMGDH, with tightly bound THF, reacted with formaldehyde generated during the reaction to form 5,10-methylene-THF. This effectively scavenged the formaldehyde to protect the enzyme. Recently, post-translational modifications on histone tails have been shown to be responsible for epigenetic regulation of gene expression. One of these modifications is methylation of lysine residues. The first enzyme discovered to accomplish demethylation of these modified histones was histone lysine demethylase (LSD1). LSD1 specifically removes methyl groups from di- and mono-methylated lysines at position 4 of histone 3. This enzyme contained tightly bound FAD and the products of the reaction were the demethylated lysine residue and formaldehyde. The mechanism of LSD1 demethylation is analogous to the mechanism previously postulated for DMGDH, i.e. oxidation of the N-methyl bond to the methylene imine followed by hydrolysis to generate formaldehyde. This suggested that THF might also be involved in the LSD1 reaction to scavenge the formaldehyde produced. Our hypotheses are that THF is bound to native LSD1 by analogy to DMGDH and SDH and that the bound THF serves to protect the FAD class of histone demethylases from the destructive effects of formaldehyde generation by formation of 5,10-methylene-THF. We present pilot data showing that decreased folate in livers as a result of dietary folate deficiency is associated with increased levels of methylated lysine 4 of histone 3. This can be a result of decreased LSD1 activity resulting from the decreased folate available to scavenge the formaldehyde produced at the active site caused by the folate deficiency. Because LSD1 can regulate gene expression this suggests that folate may play a more important role than simply serving as a carrier of one-carbon units and be a factor in other diseases associated with low folate.
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crystal structure of the histone lysine specific demethylase lsd1 complexed with tetrahydrofolate
Protein Science, 2014Co-Authors: Zigmund Luka, Svetlana Pakhomova, Lioudmila V Loukachevitch, Wade M Calcutt, Marcia E Newcomer, Conrad WagnerAbstract:An important epigenetic modification is the methylation/demethylation of histone lysine residues. The first histone demethylase to be discovered was a lysine-specific demethylase 1, LSD1, a flavin containing enzyme which carries out the demethylation of di- and monomethyllysine 4 in histone H3. The removed methyl groups are oxidized to formaldehyde. This reaction is similar to those performed by dimethylglycine Dehydrogenase and Sarcosine Dehydrogenase, in which protein-bound tetrahydrofolate (THF) was proposed to serve as an acceptor of the generated formaldehyde. We showed earlier that LSD1 binds THF with high affinity which suggests its possible participation in the histone demethylation reaction. In the cell, LSD1 interacts with co-repressor for repressor element 1 silencing transcription factor (CoREST). In order to elucidate the role of folate in the demethylating reaction we solved the crystal structure of the LSD1–CoREST–THF complex. In the complex, the folate-binding site is located in the active center in close proximity to flavin adenine dinucleotide. This position of the folate suggests that the bound THF accepts the formaldehyde generated in the course of histone demethylation to form 5,10-methylene-THF. We also show the formation of 5,10-methylene-THF during the course of the enzymatic reaction in the presence of THF by mass spectrometry. Production of this form of folate could act to prevent accumulation of potentially toxic formaldehyde in the cell. These studies suggest that folate may play a role in the epigenetic control of gene expression in addition to its traditional role in the transfer of one-carbon units in metabolism.
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histone demethylase lsd1 is a folate binding protein
Biochemistry, 2011Co-Authors: Zigmund Luka, Lioudmila V Loukachevitch, Frank R Moss, Darryl J Bornhop, Conrad WagnerAbstract:Methylation of lysine residues in histones has been known to serve a regulatory role in gene expression. Although enzymatic removal of the methyl groups was discovered as early as 1973, the enzymes responsible for their removal were isolated and their mechanism of action was described only recently. The first enzyme to show such activity was LSD1, a flavin-containing enzyme that removes the methyl groups from lysines 4 and 9 of histone 3 with the generation of formaldehyde from the methyl group. This reaction is similar to the previously described demethylation reactions conducted by the enzymes dimethylglycine Dehydrogenase and Sarcosine Dehydrogenase, in which protein-bound tetrahydrofolate serves as an accepter of the formaldehyde that is generated. We now show that nuclear extracts of HeLa cells contain LSD1 that is associated with folate. Using the method of back-scattering interferometry, we have measured the binding of various forms of folate to both full-length LSD1 and a truncated form of LSD1 in free solution. The 6R,S form of the natural pentaglutamate form of tetrahydrofolate bound with the highest affinity (K(d) = 2.8 μM) to full-length LSD1. The fact that folate participates in the enzymatic demethylation of histones provides an opportunity for this micronutrient to play a role in the epigenetic control of gene expression.
Amjad P. Khan - One of the best experts on this subject based on the ideXlab platform.
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the role of Sarcosine metabolism in prostate cancer progression
Neoplasia, 2013Co-Authors: Amjad P. Khan, Thekkelnaycke M Rajendiran, Bushra Ateeq, Jyoti N Athanikar, Ganesh S. Palapattu, Javed Siddiqui, Anastasia K Yocum, Irfan A. Asangani, George MichailidisAbstract:Metabolomic profiling of prostate cancer (PCa) progression identified markedly elevated levels of Sarcosine (N-methyl glycine) in metastatic PCa and modest but significant elevation of the metabolite in PCa urine. Here, we examine the role of key enzymes associated with Sarcosine metabolism in PCa progression. Consistent with our earlier report, Sarcosine levels were significantly elevated in PCa urine sediments compared to controls, with a modest area under the receiver operating characteristic curve of 0.71. In addition, the expression of Sarcosine biosynthetic enzyme, glycine N-methyltransferase (GNMT), was elevated in PCa tissues, while Sarcosine Dehydrogenase (SARDH) and pipecolic acid oxidase (PIPOX), which metabolize Sarcosine, were reduced in prostate tumors. Consistent with this, GNMT promoted the oncogenic potential of prostate cells by facilitating Sarcosine production, while SARDH and PIPOX reduced the oncogenic potential of prostate cells by metabolizing Sarcosine. Accordingly, addition of Sarcosine, but not glycine or alanine, induced invasion and intravasation in an in vivo PCa model. In contrast, GNMT knockdown or SARDH overexpression in PCa xenografts inhibited tumor growth. Taken together, these studies substantiate the role of Sarcosine in PCa progression.
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abstract 2803 the role of the Sarcosine pathway in prostate cancer progression
Cancer Research, 2011Co-Authors: Amjad P. Khan, Thekkelnaycke M Rajendiran, Bushra Ateeq, Anastasia K Yocum, Arun Sreekumar, Irfan A. Asangani, Arul M. ChinnaiyanAbstract:Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Differential metabolomic alterations occur during prostate cancer progression. Exploring the metabolome of prostate cancer progression, may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Recently, we have identified Sarcosine, an N-methyl derivative of the amino acid glycine, as a key metabolite increased most robustly in metastatic prostate cancer and detectable in the urine of men with organ-confined disease (Sreekumar et al., Nature, 2009). Here, we examined if the proximal regulatory enzymes of Sarcosine, glycine-N-methyl transferase (GNMT), Sarcosine Dehydrogenase (SARDH) and pipecolic acid oxidase (PIPOX), play a functional role in prostate cancer progression. By tissue microarray analysis, we observed that GNMT protein levels are strongly associated with prostate cancer aggressiveness. Here, we demonstrate that stable knockdown of GNMT inhibits cell proliferation, induces apoptosis, attenuates cell invasion in Matrigel coated transwells, and blocks the anchorage-independent growth of the cancerous DU145 cells. Overexpression of GNMT in benign RWPE cells showed significantly increased cell invasion and increased Sarcosine level. Importantly, knockdown of GNMT in DU145 cells also inhibited intravasation using chick chorioallantoic membrane (CAM) assay and tumor growth in xenograft assays. In contrast, we also showed that while the knockdown of Sarcosine degrading enzymes, SARDH and PIPOX, induced invasion and increased Sarcosine level in RWPE cells, the overexpression of these enzymes attenuated invasion and decreased Sarcosine level. Further, overexpression of SARDH inhibited cell proliferation, blocked the anchorage-independent growth and also inhibited intravasation using CAM assay. Taken together, this study shows that the components of the Sarcosine pathway may have potential as biomarkers of prostate cancer progression and serve as new avenues for therapeutic intervention. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2803. doi:10.1158/1538-7445.AM2011-2803
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metabolomic profiles delineate potential role for Sarcosine in prostate cancer progression
Nature, 2009Co-Authors: Arun Sreekumar, Thekkelnaycke M Rajendiran, Laila M Poisson, Robert J. Lonigro, Bharathi Laxman, Jindan Yu, Amjad P. Khan, Yong Li, Mukesh K. NyatiAbstract:A systematic analysis of metabolites in prostate cancer samples has led to the discovery that Sarcosine, an amino acid common in many biological tissues including muscle, is highly elevated in aggressive prostate cancers and detectable in the urine of men with prostate cancer. This makes Sarcosine a candidate biomarker for prostate cancer diagnosis. Targeted knockdown of the enzyme that generates Sarcosine from glycine attenuated prostate cell invasion in mice, pointing to a possible role in metastasis, and adding the Sarcosine pathway to the list of possible therapeutic targets. A systematic analysis of metabolites in prostate cancer samples has led to the identification of Sarcosine as a putative biomarker detectable in urine, which could potentially be used to aid prostate cancer diagnosis. Sarcosine promotes the invasion of prostate cancer cells and may play a role in metastasis. Multiple, complex molecular events characterize cancer development and progression1,2. Deciphering the molecular networks that distinguish organ-confined disease from metastatic disease may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Although gene and protein expression have been extensively profiled in human tumours, little is known about the global metabolomic alterations that characterize neoplastic progression. Using a combination of high-throughput liquid-and-gas-chromatography-based mass spectrometry, we profiled more than 1,126 metabolites across 262 clinical samples related to prostate cancer (42 tissues and 110 each of urine and plasma). These unbiased metabolomic profiles were able to distinguish benign prostate, clinically localized prostate cancer and metastatic disease. Sarcosine, an N-methyl derivative of the amino acid glycine, was identified as a differential metabolite that was highly increased during prostate cancer progression to metastasis and can be detected non-invasively in urine. Sarcosine levels were also increased in invasive prostate cancer cell lines relative to benign prostate epithelial cells. Knockdown of glycine-N-methyl transferase, the enzyme that generates Sarcosine from glycine, attenuated prostate cancer invasion. Addition of exogenous Sarcosine or knockdown of the enzyme that leads to Sarcosine degradation, Sarcosine Dehydrogenase, induced an invasive phenotype in benign prostate epithelial cells. Androgen receptor and the ERG gene fusion product coordinately regulate components of the Sarcosine pathway. Here, by profiling the metabolomic alterations of prostate cancer progression, we reveal Sarcosine as a potentially important metabolic intermediary of cancer cell invasion and aggressivity.
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Metabolomic profiles delineate potential role for Sarcosine in prostate cancer progression
Nature, 2009Co-Authors: Arun Sreekumar, Thekkelnaycke M Rajendiran, Laila M Poisson, Robert J. Lonigro, Bharathi Laxman, Jindan Yu, Amjad P. Khan, Yong LiAbstract:Multiple, complex molecular events characterize cancer development and progression. Deciphering the molecular networks that distinguish organ-confined disease from metastatic disease may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Although gene and protein expression have been extensively profiled in human tumours, little is known about the global metabolomic alterations that characterize neoplastic progression. Using a combination of high-throughput liquid-and-gas-chromatography-based mass spectrometry, we profiled more than 1,126 metabolites across 262 clinical samples related to prostate cancer (42 tissues and 110 each of urine and plasma). These unbiased metabolomic profiles were able to distinguish benign prostate, clinically localized prostate cancer and metastatic disease. Sarcosine, an N-methyl derivative of the amino acid glycine, was identified as a differential metabolite that was highly increased during prostate cancer progression to metastasis and can be detected non-invasively in urine. Sarcosine levels were also increased in invasive prostate cancer cell lines relative to benign prostate epithelial cells. Knockdown of glycine-N-methyl transferase, the enzyme that generates Sarcosine from glycine, attenuated prostate cancer invasion. Addition of exogenous Sarcosine or knockdown of the enzyme that leads to Sarcosine degradation, Sarcosine Dehydrogenase, induced an invasive phenotype in benign prostate epithelial cells. Androgen receptor and the ERG gene fusion product coordinately regulate components of the Sarcosine pathway. Here, by profiling the metabolomic alterations of prostate cancer progression, we reveal Sarcosine as a potentially important metabolic intermediary of cancer cell invasion and aggressivity.
Lioudmila V Loukachevitch - One of the best experts on this subject based on the ideXlab platform.
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folate deficiency affects histone methylation
Medical Hypotheses, 2016Co-Authors: Benjamin A Garcia, Lioudmila V Loukachevitch, Zigmund Luka, Natarajan V Bhanu, Conrad WagnerAbstract:Formaldehyde is extremely toxic reacting with proteins to crosslinks peptide chains. Formaldehyde is a metabolic product in many enzymatic reactions and the question of how these enzymes are protected from the formaldehyde that is generated has largely remained unanswered. Early experiments from our laboratory showed that two liver mitochondrial enzymes, dimethylglycine Dehydrogenase (DMGDH) and Sarcosine Dehydrogenase (SDH) catalyze oxidative demethylation reactions (Sarcosine is a common name for monomethylglycine). The enzymatic products of these enzymes were the demethylated substrates and formaldehyde, produced from the removed methyl group. Both DMGDH and SDH contain FAD and both have tightly bound tetrahydrofolate (THF), a folate coenzyme. THF binds reversibly with formaldehyde to form 5,10-methylene-THF. At that time we showed that purified DMGDH, with tightly bound THF, reacted with formaldehyde generated during the reaction to form 5,10-methylene-THF. This effectively scavenged the formaldehyde to protect the enzyme. Recently, post-translational modifications on histone tails have been shown to be responsible for epigenetic regulation of gene expression. One of these modifications is methylation of lysine residues. The first enzyme discovered to accomplish demethylation of these modified histones was histone lysine demethylase (LSD1). LSD1 specifically removes methyl groups from di- and mono-methylated lysines at position 4 of histone 3. This enzyme contained tightly bound FAD and the products of the reaction were the demethylated lysine residue and formaldehyde. The mechanism of LSD1 demethylation is analogous to the mechanism previously postulated for DMGDH, i.e. oxidation of the N-methyl bond to the methylene imine followed by hydrolysis to generate formaldehyde. This suggested that THF might also be involved in the LSD1 reaction to scavenge the formaldehyde produced. Our hypotheses are that THF is bound to native LSD1 by analogy to DMGDH and SDH and that the bound THF serves to protect the FAD class of histone demethylases from the destructive effects of formaldehyde generation by formation of 5,10-methylene-THF. We present pilot data showing that decreased folate in livers as a result of dietary folate deficiency is associated with increased levels of methylated lysine 4 of histone 3. This can be a result of decreased LSD1 activity resulting from the decreased folate available to scavenge the formaldehyde produced at the active site caused by the folate deficiency. Because LSD1 can regulate gene expression this suggests that folate may play a more important role than simply serving as a carrier of one-carbon units and be a factor in other diseases associated with low folate.
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crystal structure of the histone lysine specific demethylase lsd1 complexed with tetrahydrofolate
Protein Science, 2014Co-Authors: Zigmund Luka, Svetlana Pakhomova, Lioudmila V Loukachevitch, Wade M Calcutt, Marcia E Newcomer, Conrad WagnerAbstract:An important epigenetic modification is the methylation/demethylation of histone lysine residues. The first histone demethylase to be discovered was a lysine-specific demethylase 1, LSD1, a flavin containing enzyme which carries out the demethylation of di- and monomethyllysine 4 in histone H3. The removed methyl groups are oxidized to formaldehyde. This reaction is similar to those performed by dimethylglycine Dehydrogenase and Sarcosine Dehydrogenase, in which protein-bound tetrahydrofolate (THF) was proposed to serve as an acceptor of the generated formaldehyde. We showed earlier that LSD1 binds THF with high affinity which suggests its possible participation in the histone demethylation reaction. In the cell, LSD1 interacts with co-repressor for repressor element 1 silencing transcription factor (CoREST). In order to elucidate the role of folate in the demethylating reaction we solved the crystal structure of the LSD1–CoREST–THF complex. In the complex, the folate-binding site is located in the active center in close proximity to flavin adenine dinucleotide. This position of the folate suggests that the bound THF accepts the formaldehyde generated in the course of histone demethylation to form 5,10-methylene-THF. We also show the formation of 5,10-methylene-THF during the course of the enzymatic reaction in the presence of THF by mass spectrometry. Production of this form of folate could act to prevent accumulation of potentially toxic formaldehyde in the cell. These studies suggest that folate may play a role in the epigenetic control of gene expression in addition to its traditional role in the transfer of one-carbon units in metabolism.
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histone demethylase lsd1 is a folate binding protein
Biochemistry, 2011Co-Authors: Zigmund Luka, Lioudmila V Loukachevitch, Frank R Moss, Darryl J Bornhop, Conrad WagnerAbstract:Methylation of lysine residues in histones has been known to serve a regulatory role in gene expression. Although enzymatic removal of the methyl groups was discovered as early as 1973, the enzymes responsible for their removal were isolated and their mechanism of action was described only recently. The first enzyme to show such activity was LSD1, a flavin-containing enzyme that removes the methyl groups from lysines 4 and 9 of histone 3 with the generation of formaldehyde from the methyl group. This reaction is similar to the previously described demethylation reactions conducted by the enzymes dimethylglycine Dehydrogenase and Sarcosine Dehydrogenase, in which protein-bound tetrahydrofolate serves as an accepter of the formaldehyde that is generated. We now show that nuclear extracts of HeLa cells contain LSD1 that is associated with folate. Using the method of back-scattering interferometry, we have measured the binding of various forms of folate to both full-length LSD1 and a truncated form of LSD1 in free solution. The 6R,S form of the natural pentaglutamate form of tetrahydrofolate bound with the highest affinity (K(d) = 2.8 μM) to full-length LSD1. The fact that folate participates in the enzymatic demethylation of histones provides an opportunity for this micronutrient to play a role in the epigenetic control of gene expression.
Thekkelnaycke M Rajendiran - One of the best experts on this subject based on the ideXlab platform.
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the role of Sarcosine metabolism in prostate cancer progression
Neoplasia, 2013Co-Authors: Amjad P. Khan, Thekkelnaycke M Rajendiran, Bushra Ateeq, Jyoti N Athanikar, Ganesh S. Palapattu, Javed Siddiqui, Anastasia K Yocum, Irfan A. Asangani, George MichailidisAbstract:Metabolomic profiling of prostate cancer (PCa) progression identified markedly elevated levels of Sarcosine (N-methyl glycine) in metastatic PCa and modest but significant elevation of the metabolite in PCa urine. Here, we examine the role of key enzymes associated with Sarcosine metabolism in PCa progression. Consistent with our earlier report, Sarcosine levels were significantly elevated in PCa urine sediments compared to controls, with a modest area under the receiver operating characteristic curve of 0.71. In addition, the expression of Sarcosine biosynthetic enzyme, glycine N-methyltransferase (GNMT), was elevated in PCa tissues, while Sarcosine Dehydrogenase (SARDH) and pipecolic acid oxidase (PIPOX), which metabolize Sarcosine, were reduced in prostate tumors. Consistent with this, GNMT promoted the oncogenic potential of prostate cells by facilitating Sarcosine production, while SARDH and PIPOX reduced the oncogenic potential of prostate cells by metabolizing Sarcosine. Accordingly, addition of Sarcosine, but not glycine or alanine, induced invasion and intravasation in an in vivo PCa model. In contrast, GNMT knockdown or SARDH overexpression in PCa xenografts inhibited tumor growth. Taken together, these studies substantiate the role of Sarcosine in PCa progression.
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abstract 2803 the role of the Sarcosine pathway in prostate cancer progression
Cancer Research, 2011Co-Authors: Amjad P. Khan, Thekkelnaycke M Rajendiran, Bushra Ateeq, Anastasia K Yocum, Arun Sreekumar, Irfan A. Asangani, Arul M. ChinnaiyanAbstract:Proceedings: AACR 102nd Annual Meeting 2011‐‐ Apr 2‐6, 2011; Orlando, FL Differential metabolomic alterations occur during prostate cancer progression. Exploring the metabolome of prostate cancer progression, may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Recently, we have identified Sarcosine, an N-methyl derivative of the amino acid glycine, as a key metabolite increased most robustly in metastatic prostate cancer and detectable in the urine of men with organ-confined disease (Sreekumar et al., Nature, 2009). Here, we examined if the proximal regulatory enzymes of Sarcosine, glycine-N-methyl transferase (GNMT), Sarcosine Dehydrogenase (SARDH) and pipecolic acid oxidase (PIPOX), play a functional role in prostate cancer progression. By tissue microarray analysis, we observed that GNMT protein levels are strongly associated with prostate cancer aggressiveness. Here, we demonstrate that stable knockdown of GNMT inhibits cell proliferation, induces apoptosis, attenuates cell invasion in Matrigel coated transwells, and blocks the anchorage-independent growth of the cancerous DU145 cells. Overexpression of GNMT in benign RWPE cells showed significantly increased cell invasion and increased Sarcosine level. Importantly, knockdown of GNMT in DU145 cells also inhibited intravasation using chick chorioallantoic membrane (CAM) assay and tumor growth in xenograft assays. In contrast, we also showed that while the knockdown of Sarcosine degrading enzymes, SARDH and PIPOX, induced invasion and increased Sarcosine level in RWPE cells, the overexpression of these enzymes attenuated invasion and decreased Sarcosine level. Further, overexpression of SARDH inhibited cell proliferation, blocked the anchorage-independent growth and also inhibited intravasation using CAM assay. Taken together, this study shows that the components of the Sarcosine pathway may have potential as biomarkers of prostate cancer progression and serve as new avenues for therapeutic intervention. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 2803. doi:10.1158/1538-7445.AM2011-2803
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metabolomic profiles delineate potential role for Sarcosine in prostate cancer progression
Nature, 2009Co-Authors: Arun Sreekumar, Thekkelnaycke M Rajendiran, Laila M Poisson, Robert J. Lonigro, Bharathi Laxman, Jindan Yu, Amjad P. Khan, Yong Li, Mukesh K. NyatiAbstract:A systematic analysis of metabolites in prostate cancer samples has led to the discovery that Sarcosine, an amino acid common in many biological tissues including muscle, is highly elevated in aggressive prostate cancers and detectable in the urine of men with prostate cancer. This makes Sarcosine a candidate biomarker for prostate cancer diagnosis. Targeted knockdown of the enzyme that generates Sarcosine from glycine attenuated prostate cell invasion in mice, pointing to a possible role in metastasis, and adding the Sarcosine pathway to the list of possible therapeutic targets. A systematic analysis of metabolites in prostate cancer samples has led to the identification of Sarcosine as a putative biomarker detectable in urine, which could potentially be used to aid prostate cancer diagnosis. Sarcosine promotes the invasion of prostate cancer cells and may play a role in metastasis. Multiple, complex molecular events characterize cancer development and progression1,2. Deciphering the molecular networks that distinguish organ-confined disease from metastatic disease may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Although gene and protein expression have been extensively profiled in human tumours, little is known about the global metabolomic alterations that characterize neoplastic progression. Using a combination of high-throughput liquid-and-gas-chromatography-based mass spectrometry, we profiled more than 1,126 metabolites across 262 clinical samples related to prostate cancer (42 tissues and 110 each of urine and plasma). These unbiased metabolomic profiles were able to distinguish benign prostate, clinically localized prostate cancer and metastatic disease. Sarcosine, an N-methyl derivative of the amino acid glycine, was identified as a differential metabolite that was highly increased during prostate cancer progression to metastasis and can be detected non-invasively in urine. Sarcosine levels were also increased in invasive prostate cancer cell lines relative to benign prostate epithelial cells. Knockdown of glycine-N-methyl transferase, the enzyme that generates Sarcosine from glycine, attenuated prostate cancer invasion. Addition of exogenous Sarcosine or knockdown of the enzyme that leads to Sarcosine degradation, Sarcosine Dehydrogenase, induced an invasive phenotype in benign prostate epithelial cells. Androgen receptor and the ERG gene fusion product coordinately regulate components of the Sarcosine pathway. Here, by profiling the metabolomic alterations of prostate cancer progression, we reveal Sarcosine as a potentially important metabolic intermediary of cancer cell invasion and aggressivity.
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Metabolomic profiles delineate potential role for Sarcosine in prostate cancer progression
Nature, 2009Co-Authors: Arun Sreekumar, Thekkelnaycke M Rajendiran, Laila M Poisson, Robert J. Lonigro, Bharathi Laxman, Jindan Yu, Amjad P. Khan, Yong LiAbstract:Multiple, complex molecular events characterize cancer development and progression. Deciphering the molecular networks that distinguish organ-confined disease from metastatic disease may lead to the identification of critical biomarkers for cancer invasion and disease aggressiveness. Although gene and protein expression have been extensively profiled in human tumours, little is known about the global metabolomic alterations that characterize neoplastic progression. Using a combination of high-throughput liquid-and-gas-chromatography-based mass spectrometry, we profiled more than 1,126 metabolites across 262 clinical samples related to prostate cancer (42 tissues and 110 each of urine and plasma). These unbiased metabolomic profiles were able to distinguish benign prostate, clinically localized prostate cancer and metastatic disease. Sarcosine, an N-methyl derivative of the amino acid glycine, was identified as a differential metabolite that was highly increased during prostate cancer progression to metastasis and can be detected non-invasively in urine. Sarcosine levels were also increased in invasive prostate cancer cell lines relative to benign prostate epithelial cells. Knockdown of glycine-N-methyl transferase, the enzyme that generates Sarcosine from glycine, attenuated prostate cancer invasion. Addition of exogenous Sarcosine or knockdown of the enzyme that leads to Sarcosine degradation, Sarcosine Dehydrogenase, induced an invasive phenotype in benign prostate epithelial cells. Androgen receptor and the ERG gene fusion product coordinately regulate components of the Sarcosine pathway. Here, by profiling the metabolomic alterations of prostate cancer progression, we reveal Sarcosine as a potentially important metabolic intermediary of cancer cell invasion and aggressivity.
