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Dominique Leprince - One of the best experts on this subject based on the ideXlab platform.
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Phosphorylation of HIC1 (Hypermethylated in Cancer 1) Ser694 by ATM is essential for DNA repair.
2021Co-Authors: Sonia Paget, Marion Dubuissez, Ingrid Loison, Vanessa Dehennaut, Nathalie Spruyt, Adeline Page, Dominique LeprinceAbstract:The tumor suppressor gene HIC1 (Hypermethylated in Cancer 1) encodes a transcriptional repressor involved in the DNA-damage response. A SUMOylation increase on HIC1 Lysine314 favors the direct transcriptional repression of SIRT1 and thus the P53-dependent apoptotic response to irreparable DNA double strand breaks (DSBs). HIC1 is also essential for DSBs repair but in a SUMOylation-independent manner. Here, we show that repairable DSBs induced by a 1 h Etoposide treatment results in three specific posttranslational modifications (PTMs) of HIC1. Two of these PTMs, phosphorylation of Serine 694 and Acetylation of Lysine 623 are located in the conserved HIC1 C-terminal region located downstream of the Zinc Finger DNA-binding domain. By contrast, phosphorylation of Serine 285 found in the poorly conserved central region is unique to the human protein. We showed that Ser694 phosphorylation is mediated mainly by the PIKK kinase ATM and is essential for the DNA repair activity of HIC1 as demonstrated by the lack of efficiency of the S694A point mutant in Comet assays. Thus, our results provide the first evidence for a functional role of the conserved HIC1 C-terminal region as a novel ATM substrate that plays an essential role in the cellular HIC1-mediated cellular response to repairable DSBs.
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HIC1 (hypermethylated in cancer 1) SUMOylation is dispensable for DNA repair but is essential for the apoptotic DNA damage response (DDR) to irreparable DNA double-strand breaks (DSBs)
2016Co-Authors: Sonia Paget, Marion Dubuissez, Ingrid Loison, Vanessa Dehennaut, Joe Nassour, Brennan Harmon, Nathalie Spruyt, Corinne Abbadie, Brian R. Rood, Dominique LeprinceAbstract:// Sonia Paget 1 , Marion Dubuissez 1, 4 , Vanessa Dehennaut 1 , Joe Nassour 1, 5 , Brennan T. Harmon 2 , Nathalie Spruyt 1 , Ingrid Loison 1 , Corinne Abbadie 1 , Brian R. Rood 3 , Dominique Leprince 1 1 University Lille, CNRS, Institut Pasteur de Lille, UMR 8161-M3T-Mechanisms of Tumorigenesis and Targeted Therapies, Lille, France 2 Genomics Core, Children's National Medical Center, Washington DC, USA 3 Center for Cancer and Immunology Research, Children's National Medical Center, Washington DC, USA 4 Present Address: Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Boulevard l'Assomption Montreal, Canada 5 Present Address: The Salk Institute for Biological Studies, Molecular and Cell Biology Department, La Jolla, California, USA Correspondence to: Dominique Leprince, email: dominique.leprince@ibl.cnrs.fr Keywords: DNA damage response, HIC1, ATM, MTA1, SUMOylation Received: June 14, 2016 Accepted: November 23, 2016 Published: December 07, 2016 ABSTRACT The tumor suppressor gene HIC1 (Hypermethylated In Cancer 1) encodes a transcriptional repressor mediating the p53-dependent apoptotic response to irreparable DNA double-strand breaks (DSBs) through direct transcriptional repression of SIRT1 . HIC1 is also essential for DSB repair as silencing of endogenous HIC1 in BJ-hTERT fibroblasts significantly delays DNA repair in functional Comet assays. HIC1 SUMOylation favours its interaction with MTA1, a component of NuRD complexes. In contrast with irreparable DSBs induced by 16-hours of etoposide treatment, we show that repairable DSBs induced by 1 h etoposide treatment do not increase HIC1 SUMOylation or its interaction with MTA1. Furthermore, HIC1 SUMOylation is dispensable for DNA repair since the non-SUMOylatable E316A mutant is as efficient as wt HIC1 in Comet assays. Upon induction of irreparable DSBs, the ATM-mediated increase of HIC1 SUMOylation is independent of its effector kinase Chk2. Moreover, irreparable DSBs strongly increase both the interaction of HIC1 with MTA1 and MTA3 and their binding to the SIRT1 promoter. To characterize the molecular mechanisms sustained by this increased repression potential, we established global expression profiles of BJ-hTERT fibroblasts transfected with HIC1-siRNA or control siRNA and treated or not with etoposide. We identified 475 genes potentially repressed by HIC1 with cell death and cell cycle as the main cellular functions identified by pathway analysis. Among them, CXCL12 , EPHA4 , TGFβR3 and TRIB2 , also known as MTA1 target-genes, were validated by qRT-PCR analyses. Thus, our data demonstrate that HIC1 SUMOylation is important for the transcriptional response to non-repairable DSBs but dispensable for DNA repair.
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HIC1 tumor suppressor loss potentiates tlr2 nf κb signaling and promotes tissue damage associated tumorigenesis
2015Co-Authors: Lucie Janeckova, Marion Dubuissez, Dominique Leprince, Bohumil Fafilek, Vendula Pospichalova, Jolana Tureckova, Martina Vojtechova, Jan Dobeš, Nikol Baloghova, Monika HoraznaAbstract:Hypermethylated in cancer 1 (HIC1) represents a prototypic tumor suppressor gene frequently inactivated by DNA methylation in many types of solid tumors. The gene encodes a sequence-specific transcriptional repressor controlling expression of several genes involved in cell cycle or stress control. In this study, a HIC1 allele was conditionally deleted, using a Cre/loxP system, to identify genes influenced by the loss of HIC1. One of the transcripts upregulated upon HIC1 ablation is the toll-like receptor 2 (TLR2). Tlr2 expression levels increased in HIC1-deficient mouse embryonic fibroblasts (MEF) and cultured intestinal organoids or in human cells upon HIC1 knockdown. In addition, HIC1 associated with the TLR2 gene regulatory elements, as detected by chromatin immunoprecipitation, indicating that Tlr2 indeed represents a direct HIC1 target. The Tlr2 receptor senses “danger” signals of microbial or endogenous origin to trigger multiple signaling pathways, including NF-κB signaling. Interestingly, HIC1 deficiency promoted NF-κB pathway activity not only in cells stimulated with Tlr2 ligand, but also in cells treated with NF-κB activators that stimulate different surface receptors. In the intestine, HIC1 is mainly expressed in differentiated epithelial cells and its ablation leads to increased Tlr2 production. Finally, in a chemical-induced mouse model of carcinogenesis, HIC1 absence resulted in larger Tlr2-positive colonic tumors that showed increased proportion of proliferating cells. Implications: The tumor-suppressive function of HIC1 in colon is related to its inhibitory action on proproliferative signaling mediated by the Tlr2 receptor present on tumor cells. Mol Cancer Res; 13(7); 1139–48. ©2015 AACR.
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The Reelin receptors ApoER2 and VLDLR are direct target genes of HIC1 (Hypermethylated In Cancer 1).
2013Co-Authors: Marion Dubuissez, Vanessa Dehennaut, Brian R. Rood, Sébastien Pinte, Perrine Faiderbe, Dominique LeprinceAbstract:The tumor suppressor gene HIC1 (Hypermethylated In Cancer 1) is located in 17p13.3 a region frequently hypermethylated or deleted in tumors and in a contiguous-gene syndrome, the Miller-Dieker syndrome which includes classical lissencephaly (smooth brain) and severe developmental defects. HIC1 encodes a transcriptional repressor involved in the regulation of growth control, DNA damage response and cell migration properties. We previously demonstrated that the membrane-associated G-protein-coupled receptors CXCR7, ADRB2 and the tyrosine kinase receptor EphA2 are direct target genes of HIC1. Here we show that ectopic expression of HIC1 in U2OS and MDA-MB-231 cell lines decreases expression of the ApoER2 and VLDLR genes, encoding two canonical tyrosine kinase receptors for Reelin. Conversely, knock-down of endogenous HIC1 in BJ-Tert normal human fibroblasts through RNA interference results in the up-regulation of these two Reelin receptors. Finally, through chromatin immunoprecipitation (ChIP) in BJ-Tert fibroblasts, we demonstrate that HIC1 is a direct transcriptional repressor of ApoER2 and VLDLR. These data provide evidence that HIC1 is a new regulator of the Reelin pathway which is essential for the proper migration of neuronal precursors during the normal development of the cerebral cortex, of Purkinje cells in the cerebellum and of mammary epithelial cells. Deregulation of this pathway through HIC1 inactivation or deletion may contribute to its role in tumor promotion. Moreover, HIC1, through the direct transcriptional repression of ATOH1 and the Reelin receptors ApoER2 and VLDLR, could play an essential role in normal cerebellar development.
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HIC1 interacts with and modulates the activity of STAT3.
2013Co-Authors: Ying-mei Lin, Dominique Leprince, Chia-mei Wang, Jen-chong Jeng, Hsiu-ming ShihAbstract:HIC1 (hypermethylated in cancer 1) is a tumor suppressor gene, expression of which is frequently suppressed in human cancers. Very little is known about the molecular basis of HIC1 in antagonizing oncogenic pathways. Here, we report that HIC1 forms complexes with the signal transducers and activators of transcription 3 (STAT3) and attenuates STAT3-mediated transcription. STAT3 was identified as a HIC1-interacting protein by affinity capture and followed by mass spectrometry analysis. Overexpression or depletion of HIC1 resulted in decreased or increased levels of interleukin-6 (IL-6)/oncostatin M (OSM)-induced STAT3-mediated reporter activity and expression of target genes such as VEGF and c-Myc, respectively. Furthermore, HIC1 suppressing the VEGF and c-Myc promoter activity and the colony formation of MDA-MB 231 cells were STAT3-dependent. Further studies showed that HIC1 interacts with the DNA binding domain of STAT3 and suppresses the binding of STAT3 to its target gene promoters. Domain mapping study revealed that HIC1 C-terminal domain binds to STAT3. HIC1 mutant defective in STAT3 interaction reduced its repressive effect on STAT3 DNA binding activity, the reporter activity and gene expression of the VEGF and c-Myc genes, and cell growth in MDA-MB 231 cells. Altogether, our findings not only provide a novel role of HIC1 in antagonizing STAT3-mediated activation of VEGF and c-Myc gene expression and cell growth, but also elucidate a molecular basis underlying the inhibitory effect of HIC1 on STAT3 transcriptional potential.
Sébastien Pinte - One of the best experts on this subject based on the ideXlab platform.
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The Reelin receptors ApoER2 and VLDLR are direct target genes of HIC1 (Hypermethylated In Cancer 1).
2013Co-Authors: Marion Dubuissez, Vanessa Dehennaut, Brian R. Rood, Sébastien Pinte, Perrine Faiderbe, Dominique LeprinceAbstract:The tumor suppressor gene HIC1 (Hypermethylated In Cancer 1) is located in 17p13.3 a region frequently hypermethylated or deleted in tumors and in a contiguous-gene syndrome, the Miller-Dieker syndrome which includes classical lissencephaly (smooth brain) and severe developmental defects. HIC1 encodes a transcriptional repressor involved in the regulation of growth control, DNA damage response and cell migration properties. We previously demonstrated that the membrane-associated G-protein-coupled receptors CXCR7, ADRB2 and the tyrosine kinase receptor EphA2 are direct target genes of HIC1. Here we show that ectopic expression of HIC1 in U2OS and MDA-MB-231 cell lines decreases expression of the ApoER2 and VLDLR genes, encoding two canonical tyrosine kinase receptors for Reelin. Conversely, knock-down of endogenous HIC1 in BJ-Tert normal human fibroblasts through RNA interference results in the up-regulation of these two Reelin receptors. Finally, through chromatin immunoprecipitation (ChIP) in BJ-Tert fibroblasts, we demonstrate that HIC1 is a direct transcriptional repressor of ApoER2 and VLDLR. These data provide evidence that HIC1 is a new regulator of the Reelin pathway which is essential for the proper migration of neuronal precursors during the normal development of the cerebral cortex, of Purkinje cells in the cerebellum and of mammary epithelial cells. Deregulation of this pathway through HIC1 inactivation or deletion may contribute to its role in tumor promotion. Moreover, HIC1, through the direct transcriptional repression of ATOH1 and the Reelin receptors ApoER2 and VLDLR, could play an essential role in normal cerebellar development.
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Molecular dissection of the interaction between HIC1 and SIRT1.
2012Co-Authors: Vanessa Dehennaut, Ingrid Loison, Sébastien Pinte, Dominique LeprinceAbstract:Abstract HIC1 (Hypermethylated in Cancer 1) is a tumor suppressor gene frequently epigenetically silenced in human cancers. HIC1 encodes a transcriptional repressor involved in the regulation of growth control, cell survival and DNA damage response. The deacetylase SIRT1 regulates the repressive capacity of HIC1 in several fashions. First SIRT1 interacts with the BTB/POZ domain of HIC1 to form a transcriptional repression complex that prevents the transcription of SIRT1 itself. SIRT1 is also responsible of the deacetylation of the lysine 314 of HIC1 that allows its subsequent SUMOylation which in turn favors its interaction with the NuRD complex. To better understand the interplay between HIC1 and SIRT1, we performed co-immunoprecipitation experiments to define the domains essential for the HIC1/SIRT1 interaction. We demonstrated that the isolated four last zinc fingers of HIC1 were capable to interact with SIRT1 and that the amino-acids 610–677 of SIRT1 encompassing the ESA region of the deacetylase were crucial for the HIC1/SIRT1 interaction and HIC1 deacetylation. Finally we demonstrated that this interaction mainly depends on CKII-mediated phosphorylation of SIRT1 serine 659/661 which occurs upon DNA damage. Therefore, our results demonstrate that the activating acetylation to SUMOylation switch of HIC1 is favored by genotoxic stresses to regulate the DNA damage response.
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The Receptor Tyrosine Kinase EphA2 Is a Direct Target Gene of Hypermethylated in Cancer 1 (HIC1)
2011Co-Authors: Bénédicte Foveau, Brian R. Rood, Capucine Van Rechem, Sébastien Pinte, Gaylor Boulay, Dominique LeprinceAbstract:The tumor suppressor gene hypermethylated in cancer 1 (HIC1), which encodes a transcriptional repressor, is epigenetically silenced in many human tumors. Here, we show that ectopic expression of HIC1 in the highly malignant MDA-MB-231 breast cancer cell line severely impairs cell proliferation, migration, and invasion in vitro. In parallel, infection of breast cancer cell lines with a retrovirus expressing HIC1 also induces decreased mRNA and protein expression of the tyrosine kinase receptor EphA2. Moreover, chromatin immunoprecipitation (ChIP) and sequential ChIP experiments demonstrate that endogenous HIC1 proteins are bound, together with the MTA1 corepressor, to the EphA2 promoter in WI38 cells. Taken together, our results identify EphA2 as a new direct target gene of HIC1. Finally, we observe that inactivation of endogenous HIC1 through RNA interference in normal breast epithelial cells results in the up-regulation of EphA2 and is correlated with increased cellular migration. To conclude, our results involve the tumor suppressor HIC1 in the transcriptional regulation of the tyrosine kinase receptor EphA2, whose ligand ephrin-A1 is also a HIC1 target gene. Thus, loss of the regulation of this Eph pathway through HIC1 epigenetic silencing could be an important mechanism in the pathogenesis of epithelial cancers.
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differential regulation of HIC1 target genes by ctbp and nurd via an acetylation sumoylation switch in quiescent versus proliferating cells
2010Co-Authors: Capucine Van Rechem, Sébastien Pinte, Cateline Guérardel, Gaylor Boulay, Nicolas Stankovicvalentin, Dominique LeprinceAbstract:The tumor suppressor gene HIC1 encodes a transcriptional repressor involved in regulatory loops modulating P53-dependent and E2F1-dependent cell survival, growth control, and stress responses. Despite its importance, few HIC1 corepressors and target genes have been characterized thus far. Using a yeast two-hybrid approach, we identify MTA1, a subunit of the NuRD complex, as a new HIC1 corepressor. This interaction is regulated by two competitive posttranslational modifications of HIC1 at lysine 314, promotion by SUMOylation, and inhibition by acetylation. Consistent with the role of HIC1 in growth control, we demonstrate that HIC1/MTA1 complexes bind on two new target genes, Cyclin D1 and p57KIP2 in quiescent but not in growing WI38 cells. In addition, HIC1/MTA1 and HIC1/CtBP complexes differentially bind on two mutually exclusive HIC1 binding sites (HiRE) on the SIRT1 promoter. SIRT1 transcriptional activation induced by short-term serum starvation coincides with loss of occupancy of the distal sites by HIC1/MTA1 and HIC1/CtBP. Upon longer starvation, both complexes are found but on a newly identified proximal HiRE that is evolutionarily conserved and specifically enriched with repressive histone marks. Our results decipher a mechanistic link between two competitive posttranslational modifications of HIC1 and corepressor recruitment to specific genes, leading to growth control.
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Scavenger Chemokine (CXC Motif) Receptor 7 (CXCR7) Is a Direct Target Gene of HIC1 (Hypermethylated in Cancer 1)
2009Co-Authors: Capucine Van Rechem, Brian R. Rood, Majid Touka, Sébastien Pinte, Mathias Jenal, Cateline Guérardel, Keri Ramsey, Didier Monté, Agnès Bégue, Mario P. TschanAbstract:The tumor suppressor gene HIC1 (Hypermethylated in Cancer 1) that is epigenetically silenced in many human tumors and is essential for mammalian development encodes a sequence-specific transcriptional repressor. The few genes that have been reported to be directly regulated by HIC1 include ATOH1, FGFBP1, SIRT1, and E2F1. HIC1 is thus involved in the complex regulatory loops modulating p53-dependent and E2F1-dependent cell survival and stress responses. We performed genome-wide expression profiling analyses to identify new HIC1 target genes, using HIC1-deficient U2OS human osteosarcoma cells infected with adenoviruses expressing either HIC1 or GFP as a negative control. These studies identified several putative direct target genes, including CXCR7, a G-protein-coupled receptor recently identified as a scavenger receptor for the chemokine SDF-1/CXCL12. CXCR7 is highly expressed in human breast, lung, and prostate cancers. Using quantitative reverse transcription-PCR analyses, we demonstrated that CXCR7 was repressed in U2OS cells overexpressing HIC1. Inversely, inactivation of endogenous HIC1 by RNA interference in normal human WI38 fibroblasts results in up-regulation of CXCR7 and SIRT1. In silico analyses followed by deletion studies and luciferase reporter assays identified a functional and phylogenetically conserved HIC1-responsive element in the human CXCR7 promoter. Moreover, chromatin immunoprecipitation (ChIP) and ChIP upon ChIP experiments demonstrated that endogenous HIC1 proteins are bound together with the C-terminal binding protein corepressor to the CXCR7 and SIRT1 promoters in WI38 cells. Taken together, our results implicate the tumor suppressor HIC1 in the transcriptional regulation of the chemokine receptor CXCR7, a key player in the promotion of tumorigenesis in a wide variety of cell types.
Vanessa Dehennaut - One of the best experts on this subject based on the ideXlab platform.
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Phosphorylation of HIC1 (Hypermethylated in Cancer 1) Ser694 by ATM is essential for DNA repair.
2021Co-Authors: Sonia Paget, Marion Dubuissez, Ingrid Loison, Vanessa Dehennaut, Nathalie Spruyt, Adeline Page, Dominique LeprinceAbstract:The tumor suppressor gene HIC1 (Hypermethylated in Cancer 1) encodes a transcriptional repressor involved in the DNA-damage response. A SUMOylation increase on HIC1 Lysine314 favors the direct transcriptional repression of SIRT1 and thus the P53-dependent apoptotic response to irreparable DNA double strand breaks (DSBs). HIC1 is also essential for DSBs repair but in a SUMOylation-independent manner. Here, we show that repairable DSBs induced by a 1 h Etoposide treatment results in three specific posttranslational modifications (PTMs) of HIC1. Two of these PTMs, phosphorylation of Serine 694 and Acetylation of Lysine 623 are located in the conserved HIC1 C-terminal region located downstream of the Zinc Finger DNA-binding domain. By contrast, phosphorylation of Serine 285 found in the poorly conserved central region is unique to the human protein. We showed that Ser694 phosphorylation is mediated mainly by the PIKK kinase ATM and is essential for the DNA repair activity of HIC1 as demonstrated by the lack of efficiency of the S694A point mutant in Comet assays. Thus, our results provide the first evidence for a functional role of the conserved HIC1 C-terminal region as a novel ATM substrate that plays an essential role in the cellular HIC1-mediated cellular response to repairable DSBs.
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HIC1 (Hypermethylated in Cancer 1) modulates the contractile activity of prostate stromal fibroblasts and directly regulates CXCL12 expression
2020Co-Authors: Marion Dubuissez, Ingrid Loison, Sonia Paget, Vanessa Dehennaut, Nathalie Spruyt, Gaylor Boulay, Souhila Abdelfettah, Clementine De Schutter, Brian Rood, Martine Duterque-coquillaudAbstract:HIC1 (Hypermethylated In Cancer 1) a tumor suppressor gene located at 17p13.3, is frequently deleted or epigenetically silenced in many human tumors. HIC1 encodes a transcriptional repressor involved in various aspects of the DNA damage response and in complex regulatory loops with P53 and SIRT1. HIC1 expression in normal prostate tissues has not yet been investigated in detail. Here, we demonstrated by immunohistochemistry that detectable HIC1 expression is restricted to the stroma of both normal and tumor prostate tissues. By RT-qPCR, we showed that HIC1 is poorly expressed in all tested prostate epithelial lineage cell types: primary (PrEC), immortalized (RWPE1) or transformed androgen-dependent (LnCAP) or androgen-independent (PC3 and DU145) prostate epithelial cells. By contrast, HIC1 is strongly expressed in primary PrSMC and immortalized (WMPY-1) prostate myofibroblastic cells. HIC1 depletion in WPMY-1 cells induced decreases in α-SMA expression and contractile capability. In addition to SLUG, we identified stromal cell-derived factor 1/C-X-C motif chemokine 12 (SDF1/CXCL12) as a new HIC1 direct target-gene. Thus, our results identify HIC1 as a tumor suppressor gene which is poorly expressed in the epithelial cells targeted by the tumorigenic process. HIC1 is expressed in stromal myofibroblasts and regulates CXCL12/SDF1 expression, thereby highlighting a complex interplay mediating the tumor promoting activity of the tumor microenvironment. Our studies provide new insights into the role of HIC1 in normal prostatic epithelial-stromal interactions through direct repression of CXCL12 and new mechanistic clues on how its loss of function through promoter hypermethylation during aging could contribute to prostatic tumors.
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HIC1 (hypermethylated in cancer 1) SUMOylation is dispensable for DNA repair but is essential for the apoptotic DNA damage response (DDR) to irreparable DNA double-strand breaks (DSBs)
2016Co-Authors: Sonia Paget, Marion Dubuissez, Ingrid Loison, Vanessa Dehennaut, Joe Nassour, Brennan Harmon, Nathalie Spruyt, Corinne Abbadie, Brian R. Rood, Dominique LeprinceAbstract:// Sonia Paget 1 , Marion Dubuissez 1, 4 , Vanessa Dehennaut 1 , Joe Nassour 1, 5 , Brennan T. Harmon 2 , Nathalie Spruyt 1 , Ingrid Loison 1 , Corinne Abbadie 1 , Brian R. Rood 3 , Dominique Leprince 1 1 University Lille, CNRS, Institut Pasteur de Lille, UMR 8161-M3T-Mechanisms of Tumorigenesis and Targeted Therapies, Lille, France 2 Genomics Core, Children's National Medical Center, Washington DC, USA 3 Center for Cancer and Immunology Research, Children's National Medical Center, Washington DC, USA 4 Present Address: Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Boulevard l'Assomption Montreal, Canada 5 Present Address: The Salk Institute for Biological Studies, Molecular and Cell Biology Department, La Jolla, California, USA Correspondence to: Dominique Leprince, email: dominique.leprince@ibl.cnrs.fr Keywords: DNA damage response, HIC1, ATM, MTA1, SUMOylation Received: June 14, 2016 Accepted: November 23, 2016 Published: December 07, 2016 ABSTRACT The tumor suppressor gene HIC1 (Hypermethylated In Cancer 1) encodes a transcriptional repressor mediating the p53-dependent apoptotic response to irreparable DNA double-strand breaks (DSBs) through direct transcriptional repression of SIRT1 . HIC1 is also essential for DSB repair as silencing of endogenous HIC1 in BJ-hTERT fibroblasts significantly delays DNA repair in functional Comet assays. HIC1 SUMOylation favours its interaction with MTA1, a component of NuRD complexes. In contrast with irreparable DSBs induced by 16-hours of etoposide treatment, we show that repairable DSBs induced by 1 h etoposide treatment do not increase HIC1 SUMOylation or its interaction with MTA1. Furthermore, HIC1 SUMOylation is dispensable for DNA repair since the non-SUMOylatable E316A mutant is as efficient as wt HIC1 in Comet assays. Upon induction of irreparable DSBs, the ATM-mediated increase of HIC1 SUMOylation is independent of its effector kinase Chk2. Moreover, irreparable DSBs strongly increase both the interaction of HIC1 with MTA1 and MTA3 and their binding to the SIRT1 promoter. To characterize the molecular mechanisms sustained by this increased repression potential, we established global expression profiles of BJ-hTERT fibroblasts transfected with HIC1-siRNA or control siRNA and treated or not with etoposide. We identified 475 genes potentially repressed by HIC1 with cell death and cell cycle as the main cellular functions identified by pathway analysis. Among them, CXCL12 , EPHA4 , TGFβR3 and TRIB2 , also known as MTA1 target-genes, were validated by qRT-PCR analyses. Thus, our data demonstrate that HIC1 SUMOylation is important for the transcriptional response to non-repairable DSBs but dispensable for DNA repair.
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The Reelin receptors ApoER2 and VLDLR are direct target genes of HIC1 (Hypermethylated In Cancer 1).
2013Co-Authors: Marion Dubuissez, Vanessa Dehennaut, Brian R. Rood, Sébastien Pinte, Perrine Faiderbe, Dominique LeprinceAbstract:The tumor suppressor gene HIC1 (Hypermethylated In Cancer 1) is located in 17p13.3 a region frequently hypermethylated or deleted in tumors and in a contiguous-gene syndrome, the Miller-Dieker syndrome which includes classical lissencephaly (smooth brain) and severe developmental defects. HIC1 encodes a transcriptional repressor involved in the regulation of growth control, DNA damage response and cell migration properties. We previously demonstrated that the membrane-associated G-protein-coupled receptors CXCR7, ADRB2 and the tyrosine kinase receptor EphA2 are direct target genes of HIC1. Here we show that ectopic expression of HIC1 in U2OS and MDA-MB-231 cell lines decreases expression of the ApoER2 and VLDLR genes, encoding two canonical tyrosine kinase receptors for Reelin. Conversely, knock-down of endogenous HIC1 in BJ-Tert normal human fibroblasts through RNA interference results in the up-regulation of these two Reelin receptors. Finally, through chromatin immunoprecipitation (ChIP) in BJ-Tert fibroblasts, we demonstrate that HIC1 is a direct transcriptional repressor of ApoER2 and VLDLR. These data provide evidence that HIC1 is a new regulator of the Reelin pathway which is essential for the proper migration of neuronal precursors during the normal development of the cerebral cortex, of Purkinje cells in the cerebellum and of mammary epithelial cells. Deregulation of this pathway through HIC1 inactivation or deletion may contribute to its role in tumor promotion. Moreover, HIC1, through the direct transcriptional repression of ATOH1 and the Reelin receptors ApoER2 and VLDLR, could play an essential role in normal cerebellar development.
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DNA Double-strand Breaks Lead to Activation of Hypermethylated in Cancer 1 (HIC1) by SUMOylation to Regulate DNA Repair
2013Co-Authors: Vanessa Dehennaut, Marion Dubuissez, Ingrid Loison, Joe Nassour, Corinne Abbadie, Dominique LeprinceAbstract:HIC1 (hypermethylated in cancer 1) is a tumor suppressor gene frequently epigenetically silenced in human cancers. HIC1 encodes a transcriptional repressor involved in the regulation of growth control and DNA damage response. We previously demonstrated that HIC1 can be either acetylated or SUMOylated on lysine 314. This deacetylation/SUMOylation switch is governed by an unusual complex made up of SIRT1 and HDAC4 which deacetylates and thereby favors SUMOylation of HIC1 by a mechanism not yet fully deciphered. This switch regulates the interaction of HIC1 with MTA1, a component of the NuRD complex and potentiates the repressor activity of HIC1. Here, we show that HIC1 silencing in human fibroblasts impacts the repair of DNA double-strand breaks whereas ectopic expression of wild-type HIC1, but not of nonsumoylatable mutants, leads to a reduced number of γH2AX foci induced by etoposide treatment. In this way, we demonstrate that DNA damage leads to (i) an enhanced HDAC4/Ubc9 interaction, (ii) the activation of SIRT1 by SUMOylation (Lys-734), and (iii) the SUMO-dependent recruitment of HDAC4 by SIRT1 which permits the deacetylation/SUMOylation switch of HIC1. Finally, we show that this increase of HIC1 SUMOylation favors the HIC1/MTA1 interaction, thus demonstrating that HIC1 regulates DNA repair in a SUMO-dependent way. Therefore, epigenetic HIC1 inactivation, which is an early step in tumorigenesis, could contribute to the accumulation of DNA mutations through impaired DNA repair and thus favor tumorigenesis.
Stephen B. Baylin - One of the best experts on this subject based on the ideXlab platform.
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Abstract LB-81: Conditional deletion of the tumor suppressor HIC1 results in aneuploidy and single-step transformation
2014Co-Authors: Anette Szczepny, Stephen B. Baylin, Lisa Mckenzie, Fernando J. Rossello, Samantha Jayesekara, Prue Russell, Gavin M. Wright, Jason E. Cain, D N WatkinsAbstract:Proceedings: AACR Annual Meeting 2014; April 5-9, 2014; San Diego, CA HIC1 is a zinc-finger transcriptional repressor frequently targeted for deletion and/or epigenetic gene silencing in cancer. In cancer cell lines, re-expression of HIC1 results in the downregulation of target genes thought to promote context-dependent tumor growth, including Sirt1 , Atoh1 , Efna1 and components of the WNT and STAT3 signalling pathway. In mouse embryonic fibroblasts, we now show that deletion of a conditional loxP allele of HIC1 results in immediate growth arrest without significant overexpression of HIC1 target genes, followed by a prolonged period of cellular quiescence. After several weeks, we then observed the spontaneous emergence of rapidly growing clones that fulfil all the criteria for transformation, associated with aneuploidy and recurrent copy number alterations. By contrast, conditional deletion of p53 using the same experimental protocol resulted in prompt immortalisation without transformation, and a stable tetraploid karyotype resembling that seen in NIH-3T3 cells. These data suggest that inactivation of HIC1 in cells undergoing replication stress in tissue culture can induce complete transformation associated with marked genomic instability. To test this hypothesis in vivo, we employed the inhaled adenoviral Cre recombinase model in order to direct loxP recombination to the airway epithelium of adult mice. As previously described by other groups, Cre activation of a conditional oncogenic KRasG12D mutant resulted in the appearance of multiple lung adenomas within 6-8 weeks following viral inhalation. By contrast, mice carrying this KRasG12D allele, as well as homozygous for the conditional HIC1lox knockout allele, developed highly aggressive adenocarcinomas with prominent pleomorphic and micropapillary histology. These data suggest a novel tumour suppressor role for HIC1 in maintaining genomic stability in replicating cells. HIC1 is known to interact with components of the SWI/SNF and PRC2 complexes, which help maintain genomic integrity by re-establishing constitutive heterochromatin following DNA replication. We therefore speculate that loss of HIC1 function may phenocopy recently described mutations in components of these chromatin-remodelling complexes such as ARID1A and BRG1 . Citation Format: Anette Szczepny, Lisa McKenzie, Samantha Jayesekara, Prue Russell, Gavin Wright, Stephen B. Baylin, Fernando J. Rossello, Jason E. Cain, David N. Watkins. Conditional deletion of the tumor suppressor HIC1 results in aneuploidy and single-step transformation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr LB-81. doi:10.1158/1538-7445.AM2014-LB-81
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cooperation between the HIC1 and ptch1 tumor suppressors in medulloblastoma
2008Co-Authors: Kimberly J Briggs, Stephen B. Baylin, Ian M Corcoranschwartz, Wei Zhang, Thomas Harcke, Wendy Devereux, Charles G Eberhart, Neil D WatkinsAbstract:Medulloblastoma is an embryonal tumor thought to arise from the granule cell precursors (GCPs) of the cerebellum. PATCHED (PTCH), an inhibitor of Hedgehog signaling, is the best-characterized tumor suppressor in medulloblastoma. However, <20% of medulloblastomas have mutations in PTCH. In the search for other tumor suppressors, interest has focused on the deletion events at the 17p13.3 locus, the most common genetic defect in medulloblastoma. This chromosomal region contains HYPERMETHYLATED IN CANCER 1 (HIC1), a transcriptional repressor that is a frequent target of epigenetic gene silencing in medulloblastoma. Here we use a mouse model of Ptch1 heterozygosity to reveal a critical tumor suppressor function for HIC1 in medulloblastoma. When compared with Ptch1 heterozygous mutants, compound Ptch1/HIC1 heterozygotes display a fourfold increased incidence of medulloblastoma. We show that HIC1 is a direct transcriptional repressor of Atonal Homolog 1 (Atoh1), a proneural transcription factor essential for cerebellar development, and show that ATOH1 expression is required for human medulloblastoma cell growth in vitro. Given that Atoh1 is also a putative target of Hh signaling, we conclude that the HIC1 and Ptch1 tumor suppressors cooperate to silence Atoh1 expression during a critical phase in GCP differentiation in which malignant transformation may lead to medulloblastoma.
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Tumor Suppressor HIC1 Directly Regulates SIRT1 to Modulate p53-Dependent DNA-Damage Responses
2005Co-Authors: Wenyong Chen, Ray Whay Chiu Yen, David H. Wang, Jianyuan Luo, Stephen B. BaylinAbstract:Hypermethylated in cancer 1 (HIC1) is an epigenetically regulated transcriptional repressor that functionally cooperates with p53 to suppress age-dependent development of cancer in mice. Here we show that the mechanism by which the loss of HIC1 function promotes tumorigenesis is via activating the stress-controlling protein SIRT1 and thereby attenuating p53 function. HIC1 forms a transcriptional repression complex with SIRT1 deacetylase, and this complex directly binds the SIRT1 promoter and represses its transcription. Inactivation of HIC1 results in upregulated SIRT1 expression in normal or cancer cells; this deacetylates and inactivates p53, allowing cells to bypass apoptosis and survive DNA damage. Inhibition of SIRT1 function in cells without HIC1 abolishes the resistance to apoptosis. Since aging increases promoter hypermethylation and epigenetic silencing of HIC1, we speculate that the resultant upregulation of SIRT1 may be a double-edged sword that both promotes survival of aging cells and increases cancer risk in mammals.
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Heterozygous disruption of HIC1 predisposes mice to a gender-dependent spectrum of malignant tumors
2003Co-Authors: Wenyong Chen, Mark G Carter, Xiaobei Zeng, Joseph L Mankowski, J G Herman, Craig N. Morrell, Ray Whay Chiu Yen, Manel Esteller, D. Neil Watkins, Stephen B. BaylinAbstract:The gene hypermethylated in cancer-1 (HIC1) encodes a zinc-finger transcription factor1 that belongs to a group of proteins known as the POZ family2. HIC1 is hypermethylated and transcriptionally silent in several types of human cancer1,3,4,5. Homozygous disruption of HIC1 impairs development and results in embryonic and perinatal lethality in mice6. Here we show that mice disrupted in the germ line for only one allele of HIC1 develop many different spontaneous malignant tumors, including a predominance of epithelial cancers in males and lymphomas and sarcomas in females. The complete loss of HIC1 function in the heterozygous mice seems to involve dense methylation of the promoter of the remaining wild-type allele. We conclude that HIC1 is a candidate tumor-suppressor gene for which loss of function in both mouse and human cancers is associated only with epigenetic modifications.
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mice deficient in the candidate tumor suppressor gene HIC1 exhibit developmental defects of structures affected in the miller dieker syndrome
2000Co-Authors: Mark G Carter, Margaret A Johns, Xiaobei Zeng, Christine M Zink, Joseph L Mankowski, David M Donovan, Stephen B. BaylinAbstract:: HIC1 is a candidate tumor suppressor gene which is frequently hypermethylated in human tumors, and its location within the Miller-Dieker syndrome's critical deletion region at chromosome 17p13.3 makes it a candidate gene for involvement in this gene deletion syndrome. To study the function of murine HIC1 in development, we have created HIC1 -deficient mice. These animals die perinatally and exhibit varying combinations of gross developmental defects throughout the second half of development, including acrania, exencephaly, cleft palate, limb abnormalities and omphalocele. These findings demonstrate a role for HIC1 in the development of structures affected in the Miller-Dieker syndrome, and provide functional evidence to strengthen its candidacy as a gene involved in this disorder.
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Phosphorylation of HIC1 (Hypermethylated in Cancer 1) Ser694 by ATM is essential for DNA repair.
2021Co-Authors: Sonia Paget, Marion Dubuissez, Ingrid Loison, Vanessa Dehennaut, Nathalie Spruyt, Adeline Page, Dominique LeprinceAbstract:The tumor suppressor gene HIC1 (Hypermethylated in Cancer 1) encodes a transcriptional repressor involved in the DNA-damage response. A SUMOylation increase on HIC1 Lysine314 favors the direct transcriptional repression of SIRT1 and thus the P53-dependent apoptotic response to irreparable DNA double strand breaks (DSBs). HIC1 is also essential for DSBs repair but in a SUMOylation-independent manner. Here, we show that repairable DSBs induced by a 1 h Etoposide treatment results in three specific posttranslational modifications (PTMs) of HIC1. Two of these PTMs, phosphorylation of Serine 694 and Acetylation of Lysine 623 are located in the conserved HIC1 C-terminal region located downstream of the Zinc Finger DNA-binding domain. By contrast, phosphorylation of Serine 285 found in the poorly conserved central region is unique to the human protein. We showed that Ser694 phosphorylation is mediated mainly by the PIKK kinase ATM and is essential for the DNA repair activity of HIC1 as demonstrated by the lack of efficiency of the S694A point mutant in Comet assays. Thus, our results provide the first evidence for a functional role of the conserved HIC1 C-terminal region as a novel ATM substrate that plays an essential role in the cellular HIC1-mediated cellular response to repairable DSBs.
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HIC1 (Hypermethylated in Cancer 1) modulates the contractile activity of prostate stromal fibroblasts and directly regulates CXCL12 expression
2020Co-Authors: Marion Dubuissez, Ingrid Loison, Sonia Paget, Vanessa Dehennaut, Nathalie Spruyt, Gaylor Boulay, Souhila Abdelfettah, Clementine De Schutter, Brian Rood, Martine Duterque-coquillaudAbstract:HIC1 (Hypermethylated In Cancer 1) a tumor suppressor gene located at 17p13.3, is frequently deleted or epigenetically silenced in many human tumors. HIC1 encodes a transcriptional repressor involved in various aspects of the DNA damage response and in complex regulatory loops with P53 and SIRT1. HIC1 expression in normal prostate tissues has not yet been investigated in detail. Here, we demonstrated by immunohistochemistry that detectable HIC1 expression is restricted to the stroma of both normal and tumor prostate tissues. By RT-qPCR, we showed that HIC1 is poorly expressed in all tested prostate epithelial lineage cell types: primary (PrEC), immortalized (RWPE1) or transformed androgen-dependent (LnCAP) or androgen-independent (PC3 and DU145) prostate epithelial cells. By contrast, HIC1 is strongly expressed in primary PrSMC and immortalized (WMPY-1) prostate myofibroblastic cells. HIC1 depletion in WPMY-1 cells induced decreases in α-SMA expression and contractile capability. In addition to SLUG, we identified stromal cell-derived factor 1/C-X-C motif chemokine 12 (SDF1/CXCL12) as a new HIC1 direct target-gene. Thus, our results identify HIC1 as a tumor suppressor gene which is poorly expressed in the epithelial cells targeted by the tumorigenic process. HIC1 is expressed in stromal myofibroblasts and regulates CXCL12/SDF1 expression, thereby highlighting a complex interplay mediating the tumor promoting activity of the tumor microenvironment. Our studies provide new insights into the role of HIC1 in normal prostatic epithelial-stromal interactions through direct repression of CXCL12 and new mechanistic clues on how its loss of function through promoter hypermethylation during aging could contribute to prostatic tumors.
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HIC1 (hypermethylated in cancer 1) SUMOylation is dispensable for DNA repair but is essential for the apoptotic DNA damage response (DDR) to irreparable DNA double-strand breaks (DSBs)
2016Co-Authors: Sonia Paget, Marion Dubuissez, Ingrid Loison, Vanessa Dehennaut, Joe Nassour, Brennan Harmon, Nathalie Spruyt, Corinne Abbadie, Brian R. Rood, Dominique LeprinceAbstract:// Sonia Paget 1 , Marion Dubuissez 1, 4 , Vanessa Dehennaut 1 , Joe Nassour 1, 5 , Brennan T. Harmon 2 , Nathalie Spruyt 1 , Ingrid Loison 1 , Corinne Abbadie 1 , Brian R. Rood 3 , Dominique Leprince 1 1 University Lille, CNRS, Institut Pasteur de Lille, UMR 8161-M3T-Mechanisms of Tumorigenesis and Targeted Therapies, Lille, France 2 Genomics Core, Children's National Medical Center, Washington DC, USA 3 Center for Cancer and Immunology Research, Children's National Medical Center, Washington DC, USA 4 Present Address: Maisonneuve-Rosemont Hospital Research Center, Maisonneuve-Rosemont Hospital, Boulevard l'Assomption Montreal, Canada 5 Present Address: The Salk Institute for Biological Studies, Molecular and Cell Biology Department, La Jolla, California, USA Correspondence to: Dominique Leprince, email: dominique.leprince@ibl.cnrs.fr Keywords: DNA damage response, HIC1, ATM, MTA1, SUMOylation Received: June 14, 2016 Accepted: November 23, 2016 Published: December 07, 2016 ABSTRACT The tumor suppressor gene HIC1 (Hypermethylated In Cancer 1) encodes a transcriptional repressor mediating the p53-dependent apoptotic response to irreparable DNA double-strand breaks (DSBs) through direct transcriptional repression of SIRT1 . HIC1 is also essential for DSB repair as silencing of endogenous HIC1 in BJ-hTERT fibroblasts significantly delays DNA repair in functional Comet assays. HIC1 SUMOylation favours its interaction with MTA1, a component of NuRD complexes. In contrast with irreparable DSBs induced by 16-hours of etoposide treatment, we show that repairable DSBs induced by 1 h etoposide treatment do not increase HIC1 SUMOylation or its interaction with MTA1. Furthermore, HIC1 SUMOylation is dispensable for DNA repair since the non-SUMOylatable E316A mutant is as efficient as wt HIC1 in Comet assays. Upon induction of irreparable DSBs, the ATM-mediated increase of HIC1 SUMOylation is independent of its effector kinase Chk2. Moreover, irreparable DSBs strongly increase both the interaction of HIC1 with MTA1 and MTA3 and their binding to the SIRT1 promoter. To characterize the molecular mechanisms sustained by this increased repression potential, we established global expression profiles of BJ-hTERT fibroblasts transfected with HIC1-siRNA or control siRNA and treated or not with etoposide. We identified 475 genes potentially repressed by HIC1 with cell death and cell cycle as the main cellular functions identified by pathway analysis. Among them, CXCL12 , EPHA4 , TGFβR3 and TRIB2 , also known as MTA1 target-genes, were validated by qRT-PCR analyses. Thus, our data demonstrate that HIC1 SUMOylation is important for the transcriptional response to non-repairable DSBs but dispensable for DNA repair.
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modifications post traductionnelles de HIC1 et de bcl11 modulant le recrutement du complexe nurd et mise en evidence de trois nouveaux genes cibles directs de HIC1
2015Co-Authors: Marion DubuissezAbstract:MTA (Metastasis Tumor Antigen) proteins family is composed of three members: MTA1, 2 and 3 which differ in their C-terminus, a disorganized domain. The N-terminal region is involved in the interaction with the NuRD corepressor complex. NuRD is recruited by transcription factors at their target genes to repress transcription. HIC1 and BCL11 proteins recruit NuRD through interaction with MTA proteins to repress their target genes. In the first part of my work, we have deciphered the mechanisms of interactions between HIC1 and BCL11 proteins which both also interacted with MTA proteins. In this context, we showed that HIC1-BCL11 interaction does not allow the direct synergistic repression of common target genes. In the second part of my work, we showed that BCL11 proteins interact with the three MTA members via their conserved MSRRKQ motif to recruit NuRD complexes. Furthermore, we identified the PKC (Protein Kinase C)-mediated phosphorylation of BCL11B Serine 2 which regulates its transcription factor’s activity during activation of human CD4+ T lymphocytes. In fact, the phosphorylation of BCL11B Serine 2 allows the switch from a transcriptional repressor to an activator during TCR activation of human CD4+ T cells. In parallel to this work, we identified SDF1 as a new direct target gene of HIC1 in these cells. The SDF1 chemokine is the common ligand for chemokine receptors CXCR4 and CXCR7 involved in the migration and in the homing of immune cells. In addition, we also identified two other new direct target genes of HIC1: ApoER2 and VLDLR encoding both receptors for Reelin. This signaling pathway is involved in the migration of neuronal precursors during cerebellar development.
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HIC1 tumor suppressor loss potentiates tlr2 nf κb signaling and promotes tissue damage associated tumorigenesis
2015Co-Authors: Lucie Janeckova, Marion Dubuissez, Dominique Leprince, Bohumil Fafilek, Vendula Pospichalova, Jolana Tureckova, Martina Vojtechova, Jan Dobeš, Nikol Baloghova, Monika HoraznaAbstract:Hypermethylated in cancer 1 (HIC1) represents a prototypic tumor suppressor gene frequently inactivated by DNA methylation in many types of solid tumors. The gene encodes a sequence-specific transcriptional repressor controlling expression of several genes involved in cell cycle or stress control. In this study, a HIC1 allele was conditionally deleted, using a Cre/loxP system, to identify genes influenced by the loss of HIC1. One of the transcripts upregulated upon HIC1 ablation is the toll-like receptor 2 (TLR2). Tlr2 expression levels increased in HIC1-deficient mouse embryonic fibroblasts (MEF) and cultured intestinal organoids or in human cells upon HIC1 knockdown. In addition, HIC1 associated with the TLR2 gene regulatory elements, as detected by chromatin immunoprecipitation, indicating that Tlr2 indeed represents a direct HIC1 target. The Tlr2 receptor senses “danger” signals of microbial or endogenous origin to trigger multiple signaling pathways, including NF-κB signaling. Interestingly, HIC1 deficiency promoted NF-κB pathway activity not only in cells stimulated with Tlr2 ligand, but also in cells treated with NF-κB activators that stimulate different surface receptors. In the intestine, HIC1 is mainly expressed in differentiated epithelial cells and its ablation leads to increased Tlr2 production. Finally, in a chemical-induced mouse model of carcinogenesis, HIC1 absence resulted in larger Tlr2-positive colonic tumors that showed increased proportion of proliferating cells. Implications: The tumor-suppressive function of HIC1 in colon is related to its inhibitory action on proproliferative signaling mediated by the Tlr2 receptor present on tumor cells. Mol Cancer Res; 13(7); 1139–48. ©2015 AACR.