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Han X, Wu T, Liu CY. Univariable and multivariable Mendelian randomization investigating the effects of telomere length on the risk of adverse pregnancy outcomes. Front Endocrinol (Lausanne) 2023; 14:1225600. [PMID: 37600718 PMCID: PMC10435990 DOI: 10.3389/fendo.2023.1225600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/19/2023] [Accepted: 07/17/2023] [Indexed: 08/22/2023] Open
Abstract
Background Numerous observational studies have revealed a correlation between telomere length (TL) and adverse pregnancy outcomes (APOs). However, the impacts of TL on APOs are still unclear. Methods Mendelian randomization (MR) was carried out using summary data from genome-wide association studies (GWAS). Inverse variance weighted (IVW) was employed as the primary analysis to explore the causal relationship between TL and APOs. The exposure data came from a GWAS dataset of IEU analysis of the United Kingdom Biobank phenotypes consisting of 472,174 European participants. Summary-level data for five APOs were obtained from the GWAS datasets of the FinnGen consortium. We also performed multivariate MR (MVMR), adjusting for smoking, alcohol intake, body mass index (BMI), and number of live births. In addition, we conducted a series of rigorous analyses to further examine the validity of our MR findings. Results After Bonferroni correction and rigorous quality control, univariable MR (UVMR) demonstrated that a shorter TL was significantly associated with an increased risk of spontaneous abortion (SA) (odds ratio [OR]: 0.815; 95% confidence interval [CI]: 0.714-0.930; P = 0.002) and preterm birth (PTB) (OR: 0.758; 95% CI: 0.632-0.908; P = 0.003) in the IVW model. There was a nominally significant relationship between TL and preeclampsia (PE) in the IVW model (OR: 0.799; 95% CI: 0.651-0.979; P = 0.031). However, no significant association was found between TL and gestational diabetes mellitus (GDM) (OR: 0.950; 95% CI: 0.804-1.122; P = 0.543) or fetal growth restriction (FGR) (OR: 1.187; 95% CI: 0.901-1.565; P = 0.223) among the five statistical models. Furthermore, we did not find a significant causal effect of APOs on TL in the reverse MR analysis. MVMR analysis showed that the causal effects of TL on SA remained significant after accounting for smoking, alcohol intake, BMI, and number of live births. Conclusion Our MR study provides robust evidence that shorter telomeres were associated with an increased risk of SA. Further work is necessary to investigate the potential mechanisms. UVMR and MVMR findings showed limited evidence that TL affects the risk of PTB, PE, GDM, and FGR, illustrating that the outcomes of previous observational studies may have been confounded.
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Affiliation(s)
- Xinyu Han
- Department of First Clinical Medical College, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Tianqiang Wu
- Department of First Clinical Medical College, Heilongjiang University of Chinese Medicine, Harbin, China
| | - Chun yan Liu
- Department of Endocrinology, The First Affiliated Hospital of Heilongjiang University of Chinese Medicine, Harbin, China
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Muoio D, Laspata N, Fouquerel E. Functions of ADP-ribose transferases in the maintenance of telomere integrity. Cell Mol Life Sci 2022; 79:215. [PMID: 35348914 PMCID: PMC8964661 DOI: 10.1007/s00018-022-04235-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Revised: 03/03/2022] [Accepted: 03/07/2022] [Indexed: 12/21/2022]
Abstract
The ADP-ribose transferase (ART) family comprises 17 enzymes that catalyze mono- or poly-ADP-ribosylation, a post-translational modification of proteins. Present in all subcellular compartments, ARTs are implicated in a growing number of biological processes including DNA repair, replication, transcription regulation, intra- and extra-cellular signaling, viral infection and cell death. Five members of the family, PARP1, PARP2, PARP3, tankyrase 1 and tankyrase 2 are mainly described for their crucial functions in the maintenance of genome stability. It is well established that the most describedrole of PARP1, 2 and 3 is the repair of DNA lesions while tankyrases 1 and 2 are crucial for maintaining the integrity of telomeres. Telomeres, nucleoprotein complexes located at the ends of eukaryotic chromosomes, utilize their unique structure and associated set of proteins to orchestrate the mechanisms necessary for their own protection and replication. While the functions of tankyrases 1 and 2 at telomeres are well known, several studies have also brought PARP1, 2 and 3 to the forefront of telomere protection. The singular quality of the telomeric environment has highlighted protein interactions and molecular pathways distinct from those described throughout the genome. The aim of this review is to provide an overview of the current knowledge on the multiple roles of PARP1, PARP2, PARP3, tankyrase 1 and tankyrase 2 in the maintenance and preservation of telomere integrity.
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Affiliation(s)
- Daniela Muoio
- UPMC Cancer Institute and Department of Pharmacology and Chemical Biology at the University of Pittsburgh, Hillman Cancer Center, 5115 Centre Avenue, Pittsburgh, PA, 15213, USA
| | - Natalie Laspata
- Department of Biochemistry and Molecular Biology, Thomas Jefferson University, 233 S. 10th street, Philadelphia, PA, 19107, USA
| | - Elise Fouquerel
- UPMC Cancer Institute and Department of Pharmacology and Chemical Biology at the University of Pittsburgh, Hillman Cancer Center, 5115 Centre Avenue, Pittsburgh, PA, 15213, USA.
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3
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Demény MA, Virág L. The PARP Enzyme Family and the Hallmarks of Cancer Part 1. Cell Intrinsic Hallmarks. Cancers (Basel) 2021; 13:cancers13092042. [PMID: 33922595 PMCID: PMC8122967 DOI: 10.3390/cancers13092042] [Citation(s) in RCA: 12] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Revised: 04/02/2021] [Accepted: 04/20/2021] [Indexed: 12/21/2022] Open
Abstract
The 17-member poly (ADP-ribose) polymerase enzyme family, also known as the ADP-ribosyl transferase diphtheria toxin-like (ARTD) enzyme family, contains DNA damage-responsive and nonresponsive members. Only PARP1, 2, 5a, and 5b are capable of modifying their targets with poly ADP-ribose (PAR) polymers; the other PARP family members function as mono-ADP-ribosyl transferases. In the last decade, PARP1 has taken center stage in oncology treatments. New PARP inhibitors (PARPi) have been introduced for the targeted treatment of breast cancer 1 or 2 (BRCA1/2)-deficient ovarian and breast cancers, and this novel therapy represents the prototype of the synthetic lethality paradigm. Much less attention has been paid to other PARPs and their potential roles in cancer biology. In this review, we summarize the roles played by all PARP enzyme family members in six intrinsic hallmarks of cancer: uncontrolled proliferation, evasion of growth suppressors, cell death resistance, genome instability, reprogrammed energy metabolism, and escape from replicative senescence. In a companion paper, we will discuss the roles of PARP enzymes in cancer hallmarks related to cancer-host interactions, including angiogenesis, invasion and metastasis, evasion of the anticancer immune response, and tumor-promoting inflammation. While PARP1 is clearly involved in all ten cancer hallmarks, an increasing body of evidence supports the role of other PARPs in modifying these cancer hallmarks (e.g., PARP5a and 5b in replicative immortality and PARP2 in cancer metabolism). We also highlight controversies, open questions, and discuss prospects of recent developments related to the wide range of roles played by PARPs in cancer biology. Some of the summarized findings may explain resistance to PARPi therapy or highlight novel biological roles of PARPs that can be therapeutically exploited in novel anticancer treatment paradigms.
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Affiliation(s)
- Máté A. Demény
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- MTA-DE Cell Biology and Signaling Research Group, University of Debrecen, 4032 Debrecen, Hungary
- Correspondence: (M.A.D.); (L.V.)
| | - László Virág
- Department of Medical Chemistry, Faculty of Medicine, University of Debrecen, 4032 Debrecen, Hungary
- MTA-DE Cell Biology and Signaling Research Group, University of Debrecen, 4032 Debrecen, Hungary
- Correspondence: (M.A.D.); (L.V.)
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4
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Comprehensive analysis of telomerase inhibition by gallotannin. Oncotarget 2018; 9:18712-18719. [PMID: 29721155 PMCID: PMC5922349 DOI: 10.18632/oncotarget.24642] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2017] [Accepted: 02/24/2018] [Indexed: 11/25/2022] Open
Abstract
Gallotannin (or tannic acid) is a naturally occurring compound that inhibits cell growth and activity of different DNA-polymerases, including telomerase. The purpose of the present study was to gain insight into the mechanism of telomerase inhibition by gallotannin. We determined that gallotannin inhibits telomerase in vitro with an half maximal inhibitory concentrations value of 130 nM, but it does not affect telomerase complex assembly and component levels in vivo. The inhibitory activity of gallotannin against telomerase provides an additional explanation for the anti-cancer activities of this compound.
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5
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Chien Y, Huang CS, Lin HC, Lu KH, Tsai PH, Lai YH, Chen KH, Lee SD, Huang YH, Wang CY. Improvement of non-alcoholic steatohepatitis by hepatocyte-like cells generated from iPSCs with Oct4/Sox2/Klf4/Parp1. Oncotarget 2018; 9:18594-18606. [PMID: 29719629 PMCID: PMC5915096 DOI: 10.18632/oncotarget.23603] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 11/17/2017] [Indexed: 12/21/2022] Open
Abstract
The prevalence of nonalcoholic fatty liver disease (NAFLD) is usually increased with age. Non-alcoholic steatohepatitis (NASH), a serious form of NAFLD, may lead to cirrhosis and end-stage liver diseases. Induced pluripotent stem cells (iPSCs) hold promising potential in personalized medicine. Although obviation of c-Myc reduces tumorigenic risk, it also largely reduced the generation of iPSCs. Recently, Poly(ADP-ribose) polymerase 1 (Parp1) has been reported to enhance cell reprogramming. In this study, we demonstrated that forced expression of Oct4/Sox2/Klf4/Parp1 (OSKP) effectively promoted iPSC generation from senescent somatic cells from 18-month-old mouse. The iPSCs presented regular pluripotent properties, ability to form smaller teratoma with smaller size, and the potential for tridermal differentiation including hepatocyte-like cells (OSKP-iPSC-Heps). Resembled to fetal hepatocytes but not senescent hepatocytes, these OSKP-iPSC-Heps possessed antioxidant ability and were resistant to oxidative insult induced by H2O2 or exogenous fatty acid. Intrasplenic transplantation of OSKP-iPSC-Heps ameliorated the triglyceride over-accumulation and hepatitis, prevented the production of inflammatory cytokines and oxidative substances, and reduced apoptotic cells in methionine/choline-deficient diet (MCDD)-fed mice. In conclusion, we demonstrated that Parp-1 promoted iPSC generation from senescent cells, which can be used for the treatment of NASH after hepatic-specific differentiation. These findings indicated that patient-derived iPSC-Heps may offer an alternative option for treatment of NASH and NASH-associated end-stage liver diseases.
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Affiliation(s)
- Yueh Chien
- Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan, ROC.,Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Chi-Shuan Huang
- Division of Colorectal Surgery, Department of Surgery, Cheng-Hsin General Hospital, Taipei, Taiwan, ROC
| | - Hsin-Chi Lin
- Faculty of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.,School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC
| | - Kai-Hsi Lu
- Department of Medical Research and Education, Cheng-Hsin General Hospital, Taipei, Taiwan, ROC
| | - Ping-Hsing Tsai
- Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan, ROC.,Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Ying-Hsiu Lai
- Department of Medical Research and Education, Cheng-Hsin General Hospital, Taipei, Taiwan, ROC
| | - Kuan-Hsuan Chen
- Institute of Clinical Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.,Department of Pharmacy, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Shou-Dong Lee
- Division of Gastroenterology, Department of Internal Medicine, Cheng-Hsin General Hospital, Taipei, Taiwan, ROC.,Division of Gastroenterology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Yi-Hsiang Huang
- Division of Gastroenterology, Department of Internal Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
| | - Chien-Ying Wang
- School of Medicine, National Yang-Ming University, Taipei, Taiwan, ROC.,Division of Trauma, Department of Emergency Medicine, Taipei Veterans General Hospital, Taipei, Taiwan, ROC
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6
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Ghorai A, Sarma A, Bhattacharyya NP, Ghosh U. Carbon ion beam triggers both caspase-dependent and caspase-independent pathway of apoptosis in HeLa and status of PARP-1 controls intensity of apoptosis. Apoptosis 2016; 20:562-80. [PMID: 25670618 DOI: 10.1007/s10495-015-1107-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
High linear energy transfer (LET) carbon ion beam (CIB) is becoming very promising tool for various cancer treatments and is more efficient than conventional low LET gamma or X-rays to kill malignant or radio-resistant cells, although detailed mechanism of cell death is still unknown. Poly (ADP-ribose) polymerase-1 (PARP-1) is a key player in DNA repair and its inhibitors are well-known as radio-sensitizer for low LET radiation. The objective of our study was to find mechanism(s) of induction of apoptosis by CIB and role of PARP-1 in CIB-induced apoptosis. We observed overall higher apoptosis in PARP-1 knocked down HeLa cells (HsiI) compared with negative control H-vector cells after irradiation with CIB (0-4 Gy). CIB activated both intrinsic and extrinsic pathways of apoptosis via caspase-9 and caspase-8 activation respectively, followed by caspase-3 activation, apoptotic body, nucleosomal ladder formation and sub-G1 accumulation. Apoptosis inducing factor translocation into nucleus in H-vector but not in HsiI cells after CIB irradiation contributed caspase-independent apoptosis. Higher p53 expression was observed in HsiI cells compared with H-vector after exposure with CIB. Notably, we observed about 37 % fall of mitochondrial membrane potential, activation of caspase-9 and caspase-3 and mild activation of caspase-8 without any detectable apoptotic body formation in un-irradiated HsiI cells. We conclude that reduction of PARP-1 expression activates apoptotic signals via intrinsic and extrinsic pathways in un-irradiated cells. CIB irradiation further intensified both intrinsic and extrinsic pathways of apoptosis synergistically along with up-regulation of p53 in HsiI cells resulting overall higher apoptosis in HsiI than H-vector.
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Affiliation(s)
- Atanu Ghorai
- Department of Biochemistry & Biophysics, University of Kalyani, Kalyani, 741235, India
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7
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Ghorai A, Bhattacharyya NP, Sarma A, Ghosh U. Radiosensitivity and Induction of Apoptosis by High LET Carbon Ion Beam and Low LET Gamma Radiation: A Comparative Study. SCIENTIFICA 2014; 2014:438030. [PMID: 25018892 PMCID: PMC4083825 DOI: 10.1155/2014/438030] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2014] [Accepted: 05/22/2014] [Indexed: 05/26/2023]
Abstract
Cancer treatment with high LET heavy ion beam, especially, carbon ion beam ((12)C), is becoming very popular over conventional radiotherapy like low LET gamma or X-ray. Combination of Poly(ADP-ribose) polymerase (PARP) inhibitor with xenotoxic drugs or conventional radiation (gamma or X-ray) is the newer approach for cancer therapy. The aim of our study was to compare the radiosensitivity and induction of apoptosis by high LET (12)C and low LET gamma radiation in HeLa and PARP-1 knocked down cells. We did comet assay to detect DNA breaks, clonogenic survival assay, and cell cycle analysis to measure recovery after DNA damage. We measured apoptotic parameters like nuclear fragmentation and caspase-3 activation. DNA damage, cell killing, and induction of apoptosis were significantly higher for (12)C than gamma radiation in HeLa. Cell killing and apoptosis were further elevated upon knocking down of PARP-1. Both (12)C and gamma induced G2/M arrest although the (12)C had greater effect. Unlike the gamma, (12)C irradiation affects DNA replication as detected by S-phase delay in cell cycle analysis. So, we conclude that high LET (12)C has greater potential over low LET gamma radiation in killing cells and radiosensitization upon PARP-1 inhibition was several folds greater for (12)C than gamma.
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Affiliation(s)
- Atanu Ghorai
- Department of Biochemistry & Biophysics, University of Kalyani, Kalyani 741235, India
| | - Nitai P. Bhattacharyya
- Crystallography and Molecular Biology Division, Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064, India
| | - Asitikantha Sarma
- Inter-University Accelerator Center (IUAC), Aruna Asaf Ali Marg, New Delhi 110067, India
| | - Utpal Ghosh
- Department of Biochemistry & Biophysics, University of Kalyani, Kalyani 741235, India
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8
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Boltz KA, Jasti M, Townley JM, Shippen DE. Analysis of poly(ADP-Ribose) polymerases in Arabidopsis telomere biology. PLoS One 2014; 9:e88872. [PMID: 24551184 PMCID: PMC3923816 DOI: 10.1371/journal.pone.0088872] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2013] [Accepted: 01/17/2014] [Indexed: 11/22/2022] Open
Abstract
Maintaining the length of the telomere tract at chromosome ends is a complex process vital to normal cell division. Telomere length is controlled through the action of telomerase as well as a cadre of telomere-associated proteins that facilitate replication of the chromosome end and protect it from eliciting a DNA damage response. In vertebrates, multiple poly(ADP-ribose) polymerases (PARPs) have been implicated in the regulation of telomere length, telomerase activity and chromosome end protection. Here we investigate the role of PARPs in plant telomere biology. We analyzed Arabidopsis thaliana mutants null for PARP1 and PARP2 as well as plants treated with the PARP competitive inhibitor 3-AB. Plants deficient in PARP were hypersensitive to genotoxic stress, and expression of PARP1 and PARP2 mRNA was elevated in response to MMS or zeocin treatment or by the loss of telomerase. Additionally, PARP1 mRNA was induced in parp2 mutants, and conversely, PARP2 mRNA was induced in parp1 mutants. PARP3 mRNA, by contrast, was elevated in both parp1 and parp2 mutants, but not in seedlings treated with 3-AB or zeocin. PARP mutants and 3-AB treated plants displayed robust telomerase activity, no significant changes in telomere length, and no end-to-end chromosome fusions. Although there remains a possibility that PARPs play a role in Arabidopsis telomere biology, these findings argue that the contribution is a minor one.
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Affiliation(s)
- Kara A. Boltz
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Madhu Jasti
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Jennifer M. Townley
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
| | - Dorothy E. Shippen
- Department of Biochemistry and Biophysics, Texas A&M University, College Station, Texas, United States of America
- * E-mail:
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9
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Synthesis, structure, interaction with DNA and cytotoxicity of a luminescent copper(II) complex with a hydrazone ligand. Polyhedron 2013. [DOI: 10.1016/j.poly.2013.01.002] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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10
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The Sound of Silence: RNAi in Poly (ADP-Ribose) Research. Genes (Basel) 2012; 3:779-805. [PMID: 24705085 PMCID: PMC3899979 DOI: 10.3390/genes3040779] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2012] [Revised: 11/05/2012] [Accepted: 11/06/2012] [Indexed: 02/07/2023] Open
Abstract
Poly(ADP-ribosyl)-ation is a nonprotein posttranslational modification of proteins and plays an integral part in cell physiology and pathology. The metabolism of poly(ADP-ribose) (PAR) is regulated by its synthesis by poly(ADP-ribose) polymerases (PARPs) and on the catabolic side by poly(ADP-ribose) glycohydrolase (PARG). PARPs convert NAD+ molecules into PAR chains that interact covalently or noncovalently with target proteins and thereby modify their structure and functions. PAR synthesis is activated when PARP1 and PARP2 bind to DNA breaks and these two enzymes account for almost all PAR formation after genotoxic stress. PARG cleaves PAR molecules into free PAR and finally ADP-ribose (ADPR) moieties, both acting as messengers in cellular stress signaling. In this review, we discuss the potential of RNAi to manipulate the levels of PARPs and PARG, and consequently those of PAR and ADPR, and compare the results with those obtained after genetic or chemical disruption.
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11
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Synthesis, structural characterisation and cytotoxicity of new iron(III) complexes with pyrazolyl thiosemicabazones. Polyhedron 2012. [DOI: 10.1016/j.poly.2011.10.033] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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12
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Simbulan-Rosenthal CM, Rosenthal DS, Smulson ME. Purification and characterization of poly(ADP-ribosyl)ated DNA replication/repair complexes. Methods Mol Biol 2011; 780:165-90. [PMID: 21870261 DOI: 10.1007/978-1-61779-270-0_11] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
PARP-1, the best studied isoform and most abundantly expressed member of the PARP family of 18 proteins, catalyzes the poly(ADP-ribosyl)ation (PARylation) of various nuclear proteins and play key roles in DNA repair, genome maintenance, DNA replication, recombination, apoptosis, gene expression, and regulation of chromatin function. PARylation modulates the functions of target proteins, mainly PARP-1 itself. A multifunctional enzyme, PARP-1 has been localized within DNA replication, repair, recombination, and transcription complexes, and modifies and regulates the functions of specific components of these complexes. PARylation can regulate the activities of replicative enzymes, such as DNA polymerases α, δ, and ε, topo I and II, primase, RPA, and PCNA in isolated enzymes or within DNA replication complexes (DNA synthesome). PARP-1 and PARylation may (1) play dual roles in nuclear processes, depending on the levels of the substrate NAD and the presence of PARP-activating DNA breaks, (2) recruit acceptor proteins to certain sites or complexes through direct association or through binding to PAR and PAR-binding proteins, and (3) alters the nucleosomal structure of DNA by PARylation of nucleosomal proteins, such as histone H1 to destabilize higher order chromatin structures and promote access of DNA repair and replication enzymes as well as transcription factors to these sites. Here, we describe biochemical approaches that have been utilized in our laboratory for the purification and characterization of PARylated DNA replicative complexes. These methods can be modified for the purification of complexes involved in other nuclear processes. This chapter also briefly discusses current methods by which new PARylated complexes are being identified and studied. Identification, evaluation, and characterization of new complexes could aid in the elucidation of the molecular mechanisms by which PARylation and PARP mediates its pleiotropic roles in various nuclear processes.
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Affiliation(s)
- Cynthia M Simbulan-Rosenthal
- Department of Biochemistry and Molecular & Cellular Biology, Georgetown University School of Medicine, Washington, DC, USA
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Baroni A, De Luca A, De Filippis A, Petrazzuolo M, Manente L, Nicoletti R, Tufano MA, Buommino E. 3-O-methylfunicone, a metabolite of Penicillium pinophilum, inhibits proliferation of human melanoma cells by causing G(2) + M arrest and inducing apoptosis. Cell Prolif 2009; 42:541-53. [PMID: 19486013 DOI: 10.1111/j.1365-2184.2009.00609.x] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
OBJECTIVES Melanoma cells take advantage of impaired ability to undergo programmed cell death in response to different external stimuli and chemotherapeutic drugs; this makes prevention of tumour progression very difficult. The aim of this study was to demonstrate whether 3-O-methylfunicone (OMF), a metabolite of Penicillium pinophilum, has the ability to arrest cell population growth and to induce apoptosis in A375P (parental) and A375M (metastasis derivatived) melanoma cell lines. MATERIALS AND METHODS Cell proliferation and apoptosis were analysed by flow cytometry, DNA fragmentation, caspase-3 and caspase-9 activation, and PARP-1 cleavage. RESULTS We demonstrated that OMF affected cell proliferation in a time- and dose-dependent manner, reaching the best effect at concentration of 80 microg/ml for 24 h. Flow cytometry revealed that OMF caused significant G(2) phase arrest, which was associated with marked decrease in cyclin B1/p34(cdc2) complex and p21 induction. OMF also induced marked decrease of survivin expression. Reduced levels of apoptosis were evident after silencing p21 expression in both cell lines. Finally, the effect exercised by OMF on hTERT and TEP-1 gene expression confirmed the ability of this molecule to interfere with replicative ability of cells. CONCLUSIONS The results reported here seem to suggest that OMF as a promising molecule to include in strategies for treatment of melanoma.
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Affiliation(s)
- A Baroni
- Department of Dermatology, Second University of Naples, Naples, Italy
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14
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Deville L, Hillion J, Ségal-Bendirdjian E. Telomerase regulation in hematological cancers: a matter of stemness? Biochim Biophys Acta Mol Basis Dis 2009; 1792:229-39. [PMID: 19419697 DOI: 10.1016/j.bbadis.2009.01.016] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2008] [Revised: 01/30/2009] [Accepted: 01/30/2009] [Indexed: 01/02/2023]
Abstract
Human telomerase is a nuclear ribonucleoprotein enzyme complex that catalyzes the synthesis and extension of telomeric DNA. This enzyme is highly expressed and active in most malignant tumors while it is usually not or transiently detectable in normal somatic cells, suggesting that it plays an important role in cellular immortalization and tumorigenesis. As most leukemic cells are generally telomerase-positive and have often shortened telomeres, our understanding of how telomerase is deregulated in these diseases could help to define novel therapies targeting the telomere/telomerase complex. Nonetheless, considering that normal hematopoietic stem cells and some of their progeny do express a functional telomerase, it is tempting to consider such an activity in leukemias as a sustained stemness feature and important to understand how telomere length and telomerase activity are regulated in the various forms of leukemias.
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Affiliation(s)
- Laure Deville
- INSERM UMR-S 685, Institut d'Hématologie, Hôpital Saint-Louis, 75475 Paris cedex 10, France
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Beneke S, Cohausz O, Malanga M, Boukamp P, Althaus F, Bürkle A. Rapid regulation of telomere length is mediated by poly(ADP-ribose) polymerase-1. Nucleic Acids Res 2008; 36:6309-17. [PMID: 18835851 PMCID: PMC2577345 DOI: 10.1093/nar/gkn615] [Citation(s) in RCA: 67] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
Shelterin/telosome is a multi-protein complex at mammalian telomeres, anchored to the double-stranded region by the telomeric-repeat binding factors-1 and -2. In vitro modification of these proteins by poly(ADP-ribosyl)ation through poly(ADP-ribose) polymerases-5 (tankyrases) and -1/-2, respectively, impairs binding. Thereafter, at least telomeric-repeat binding factor-1 is degraded by the proteasome. We show that pharmacological inhibition of poly(ADP-ribose) polymerase activity in cells from two different species leads to rapid decrease in median telomere length and stabilization at a lower setting. Specific knockdown of poly(ADP-ribose) polymerase-1 by RNA interference had the same effect. The length of the single-stranded telomeric overhang as well as telomerase activity were not affected. Release of inhibition led to a fast re-gain in telomere length to control levels in cells expressing active telomerase. We conclude that poly(ADP-ribose) polymerase-1 activity and probably its interplay with telomeric-repeat binding factor-2 is an important determinant in telomere regulation. Our findings reinforce the link between poly(ADP-ribosyl)ation and aging/longevity and also impact on the use of poly(ADP-ribose) polymerase inhibitors in tumor therapy.
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Affiliation(s)
- Sascha Beneke
- Molecular Toxicology Group, Department of Biology, University of Konstanz, 78457 Konstanz, Germany.
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Ghosh U, Bhattacharyya NP. Induction of apoptosis by the inhibitors of poly(ADP-ribose)polymerase in HeLa cells. Mol Cell Biochem 2008; 320:15-23. [PMID: 18695944 DOI: 10.1007/s11010-008-9894-2] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/15/2008] [Accepted: 07/24/2008] [Indexed: 02/02/2023]
Abstract
To investigate the role of poly(ADP-ribose)polymerase (PARP) in the physiological condition of cell growth, we studied the ability of PARP inhibitors to induce apoptosis. Benzamide (BA) and 4-amino-1,8-naphthalimide (NAP), two well-known inhibitors of PARP, treatment increased nuclear fragmentation and caspase-3 activity in HeLa (Human cervical cancer cell line) cells. The increase of cellular NAD(+) level was observed in HeLa cells treated with BA in comparison with untreated control cells. For unrevealing the specific PARP family member responsible for such induction of apoptosis we knocked down and over-expressed PARP-1 gene in HeLa cells. PARP-1 knock down cells were sensitive to BA induced nuclear fragmentation and caspase-3 activation while exogenous expression of PARP-1 rendered cells resistant to BA induced apoptosis. This result indicated that inhibition of PARP-1 resulted in induction of apoptosis.
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Affiliation(s)
- Utpal Ghosh
- Department of Biochemistry & Biophysics, University of Kalyani, Kalyani 741235, India.
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