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Sandeep P, Sharma P, Luhach K, Dhiman N, Kharkwal H, Sharma B. Neuron navigators: A novel frontier with physiological and pathological implications. Mol Cell Neurosci 2023; 127:103905. [PMID: 37972804 DOI: 10.1016/j.mcn.2023.103905] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/12/2023] [Revised: 10/31/2023] [Accepted: 11/09/2023] [Indexed: 11/19/2023] Open
Abstract
Neuron navigators are microtubule plus-end tracking proteins containing basic and serine rich regions which are encoded by neuron navigator genes (NAVs). Neuron navigator proteins are essential for neurite outgrowth, neuronal migration, and overall neurodevelopment along with some other functions as well. The navigator proteins are substantially expressed in the developing brain and have been reported to be differentially expressed in various tissues at different ages. Over the years, the research has found neuron navigators to be implicated in a spectrum of pathological conditions such as developmental anomalies, neurodegenerative disorders, neuropathic pain, anxiety, cancers, and certain inflammatory conditions. The existing knowledge about neuron navigators remains sparse owing to their differential functions, undiscovered modulators, and unknown molecular mechanisms. Investigating the possible role of neuron navigators in various physiological processes and pathological conditions pose as a novel field that requires extensive research and might provide novel mechanistic insights and understanding of these aspects.
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Affiliation(s)
- Parth Sandeep
- Department of Pharmacology, Amity Institute of Pharmacy, Amity University, Uttar Pradesh, Noida, India
| | - Poonam Sharma
- Department of Pharmacology, Amity Institute of Pharmacy, Amity University, Uttar Pradesh, Noida, India
| | - Kanishk Luhach
- Department of Pharmacology, Amity Institute of Pharmacy, Amity University, Uttar Pradesh, Noida, India
| | - Neerupma Dhiman
- Amity Institute of Pharmacy, Amity University, Uttar Pradesh, Noida, India
| | - Harsha Kharkwal
- Amity Natural and Herbal Product Research, Amity Institute of Phytochemistry and Phytomedicine, Amity University, Uttar Pradesh, India
| | - Bhupesh Sharma
- Department of Pharmacology, Amity Institute of Pharmacy, Amity University, Uttar Pradesh, Noida, India.
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2
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Pongsavee M, Wisuwan K, Pongsavee K. MLH1 rs1800734 Pathogenic Variant among Patients with Colorectal Cancer in the Lower Northeastern Region of Thailand. Asian Pac J Cancer Prev 2023; 24:2911-2916. [PMID: 37642081 PMCID: PMC10685219 DOI: 10.31557/apjcp.2023.24.8.2911] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Accepted: 08/08/2023] [Indexed: 08/31/2023] Open
Abstract
BACKGROUND The -93G > A (rs1800734) polymorphism within the core promoter region of MLH1 gene is associated with MLH1 CpG island hypermethylation. This polymorphism has recently been proposed as a low penetrance variant for colorectal cancer. Many published studies have evaluated the association between the MLH1 -93G > A polymorphism and colorectal cancer risk. However, the results remain conflicting rather than conclusive. The aim of this study was to assess the association between the MLH1 -93G > A polymorphism and the risk of colorectal cancer in patients with colorectal cancer in the lower northeastern region of Thailand. METHODS One hundred fifty one samples from colorectal cancer patients and 100 samples from healthy control group were analyzed. Genomic DNA was extracted from white blood cell of all samples. The real-time polymerase chain reaction (qPCR) was used to demonstrate genetic polymorphism of MLH1 rs1800734. RESULTS This study demonstrated that the frequency of MLH1 rs1800734 in patients with colorectal cancer was higher than healthy control group. The MLH1 rs1800734 polymorphism variant AA was associated with an increased risk of colorectal cancer (p < 0.05). The MLH1 polymorphism variant AA carriers presented 1.36-folds high risk of colorectal cancer and the alcohol consumption was linked to their likelihood of developing colorectal cancer and their tumor's grade. CONCLUSION This study showed that MLH1 rs1800734 genotype AA was associated with colorectal cancer risk in the lower northeastern region of Thailand.
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Affiliation(s)
- Malinee Pongsavee
- Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Rangsit Campus, Pathum Thani, Thailand.
- Department of Medical Technology, Faculty of Allied Health Sciences, Pathumthani University, Pathum Thani, Thailand.
| | - Kamol Wisuwan
- Department of Pathology, Ubon Ratchathani Cancer Hospital, Ubon Ratchathani, Thailand.
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3
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Potts MA, Mizutani S, Garnham AL, Li Wai Suen CSN, Kueh AJ, Tai L, Pal M, Strasser A, Herold MJ. Deletion of the transcriptional regulator TFAP4 accelerates c-MYC-driven lymphomagenesis. Cell Death Differ 2023:10.1038/s41418-023-01145-w. [PMID: 36894688 DOI: 10.1038/s41418-023-01145-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/22/2023] [Accepted: 02/24/2023] [Indexed: 03/11/2023] Open
Abstract
Many lymphoid malignancies arise from deregulated c-MYC expression in cooperation with additional genetic lesions. While many of these cooperative genetic lesions have been discovered and their functions characterised, DNA sequence data of primary patient samples suggest that many more do exist. However, the nature of their contributions to c-MYC driven lymphomagenesis have not yet been investigated. We identified TFAP4 as a potent suppressor of c-MYC driven lymphoma development in a previous genome-wide CRISPR knockout screen in primary cells in vivo [1]. CRISPR deletion of TFAP4 in Eµ-MYC transgenic haematopoietic stem and progenitor cells (HSPCs) and transplantation of these manipulated HSPCs into lethally irradiated animals significantly accelerated c-MYC-driven lymphoma development. Interestingly, TFAP4 deficient Eµ-MYC lymphomas all arose at the pre-B cell stage of B cell development. This observation prompted us to characterise the transcriptional profile of pre-B cells from pre-leukaemic mice transplanted with Eµ-MYC/Cas9 HSPCs that had been transduced with sgRNAs targeting TFAP4. This analysis revealed that TFAP4 deletion reduced expression of several master regulators of B cell differentiation, such as Spi1, SpiB and Pax5, which are direct target genes of both TFAP4 and MYC. We therefore conclude that loss of TFAP4 leads to a block in differentiation during early B cell development, thereby accelerating c-MYC-driven lymphoma development.
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Affiliation(s)
- Margaret A Potts
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Shinsuke Mizutani
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.,Division of Hematology and Oncology, Department of Medicine, Kyoto Prefectural University of Medicine, Kyoto, Japan
| | - Alexandra L Garnham
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Connie S N Li Wai Suen
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Andrew J Kueh
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Lin Tai
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia
| | - Martin Pal
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.,School of Dentistry and Medical Sciences, Charles Sturt University, Wagga Wagga, NSW, Australia
| | - Andreas Strasser
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia.,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia
| | - Marco J Herold
- The Walter and Eliza Hall Institute of Medical Research, Blood Cells and Blood Cancer Division, Parkville, VIC, Australia. .,Department of Medical Biology, University of Melbourne, Parkville, VIC, Australia.
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4
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Kaller M, Shi W, Hermeking H. c-MYC-Induced AP4 Attenuates DREAM-Mediated Repression by p53. Cancers (Basel) 2023; 15:cancers15041162. [PMID: 36831504 PMCID: PMC9954515 DOI: 10.3390/cancers15041162] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2023] [Revised: 02/08/2023] [Accepted: 02/09/2023] [Indexed: 02/15/2023] Open
Abstract
BACKGROUND The deregulated expression of the c-MYC oncogene activates p53, which is presumably mediated by ARF/INK4, as well as replication-stress-induced DNA damage. Here, we aimed to determine whether the c-MYC-inducible AP4 transcription factor plays a role in this context using a genetic approach. METHODS We used a CRISPR/Cas9 approach to generate AP4- and/or p53-deficient derivatives of MCF-7 breast cancer cells harboring an ectopic, inducible c-MYC allele. Cell proliferation, senescence, DNA damage, and comprehensive RNA expression profiles were determined after activation of c-MYC. In addition, we analyzed the expression data from primary breast cancer samples. RESULTS Loss of AP4 resulted in elevated levels of both spontaneous and c-MYC-induced DNA damage, senescence, and diminished cell proliferation. Deletion of p53 in AP4-deficient cells reverted senescence and proliferation defects without affecting DNA damage levels. RNA-Seq analyses showed that loss of AP4 enhanced repression of DREAM and E2F target genes after p53 activation by c-MYC. Depletion of p21 or the DREAM complex component LIN37 abrogated this effect. These p53-dependent effects were conserved on the level of clinical and gene expression associations found in primary breast cancer tumors. CONCLUSIONS Our results establish AP4 as a pivotal factor at the crossroads of c-MYC, E2F, and p53 target gene regulation.
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Affiliation(s)
- Markus Kaller
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians-University München, D-80337 Munich, Germany
| | - Wenjing Shi
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians-University München, D-80337 Munich, Germany
| | - Heiko Hermeking
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians-University München, D-80337 Munich, Germany
- German Cancer Consortium (DKTK), Partner Site Munich, D-80336 Munich, Germany
- German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
- Correspondence: ; Tel.: +49-89-2180-73685; Fax: +49-89-2180-73697
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Transcription Factor AP4 Mediates Cell Fate Decisions: To Divide, Age, or Die. Cancers (Basel) 2021; 13:cancers13040676. [PMID: 33567514 PMCID: PMC7914591 DOI: 10.3390/cancers13040676] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2021] [Revised: 01/31/2021] [Accepted: 02/03/2021] [Indexed: 12/12/2022] Open
Abstract
Simple Summary Here, we review the literature on Activating Enhancer-Binding Protein 4 (AP4)/transcription factor AP4 (TFAP4) function and regulation and its role in cancer. Elevated expression of AP4 was detected in tumors of various organs and is associated with poor patient survival. AP4 is encoded by a Myc target gene and mediates cell fate decisions by regulating multiple processes, such as cell proliferation, epithelial-mesenchymal transition, stemness, apoptosis, and cellular senescence. Thereby, AP4 may be critical for tumor initiation and progression. In this review article, we summarize published evidence showing how AP4 functions as a transcriptional activator and repressor of a plethora of direct target genes in various physiological and pathological conditions. We also highlight the complex interactions of AP4 with c-Myc, N-Myc, p53, lncRNAs, and miRNAs in feed-back loops, which control AP4 levels and mediate AP4 functions. In the future, a better understanding of AP4 may contribute to improved prognosis and therapy of cancer. Abstract Activating Enhancer-Binding Protein 4 (AP4)/transcription factor AP4 (TFAP4) is a basic-helix-loop-helix-leucine-zipper transcription factor that was first identified as a protein bound to SV40 promoters more than 30 years ago. Almost 15 years later, AP4 was characterized as a target of the c-Myc transcription factor, which is the product of a prototypic oncogene that is activated in the majority of tumors. Interestingly, AP4 seems to represent a central hub downstream of c-Myc and N-Myc that mediates some of their functions, such as proliferation and epithelial-mesenchymal transition (EMT). Elevated AP4 expression is associated with progression of cancer and poor patient prognosis in multiple tumor types. Deletion of AP4 in mice points to roles of AP4 in the control of stemness, tumor initiation and adaptive immunity. Interestingly, ex vivo AP4 inactivation results in increased DNA damage, senescence, and apoptosis, which may be caused by defective cell cycle progression. Here, we will summarize the roles of AP4 as a transcriptional repressor and activator of target genes and the contribution of protein and non-coding RNAs encoded by these genes, in regulating the above mentioned processes. In addition, proteins interacting with or regulating AP4 and the cellular signaling pathways altered after AP4 dysregulation in tumor cells will be discussed.
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Chekini Z, Shahhoseini M, Aflatoonian R, Afsharian P. The Relationship between Functional Promoter Variants of Macrophage Migration Inhibitory Factor and Endometriosis. CELL JOURNAL 2020; 22:450-456. [PMID: 32347038 PMCID: PMC7211282 DOI: 10.22074/cellj.2021.6858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/13/2019] [Accepted: 07/08/2019] [Indexed: 11/12/2022]
Abstract
Objective Endometriosis is a common gynecological and inflammatory disorder. Macrophage migration inhibitory factor
(MIF) is a key pro-inflammatory cytokine that is secreted by accumulated active macrophages in ectopic endometrial
tissues. Two promoter polymorphisms of MIF [-794(CATT)5–8/-173G/C] were identified to susceptibility and severity of
several immune and inflammatory diseases. We aimed to evaluate the possible association between MIF promoter
polymorphisms and susceptibly to endometriosis and its corolation with mRNA level.
Materials and Methods This case-control study was performed in Royan Institute from 2015 to 2017. Polymorphisms
were evaluated in 106 endometriosis patients and 110 controls. For 17 endometrioma tissues, gene expression studies
were conducted during secretory phase of menstrual cycle. Restriction fragment length polymorphism (RFLP) analysis
was performed to determine -173G/C polymorphism and -794(CATT)5–8 were detected by sequencing. Quantitative
polymerase chain reaction (Q-PCR) was carried out to determine MIF expression level.
Results Homozygote of CATT7 was observed only in endometriosis whilst we did not detect the significant allele and
genotype variation in both groups. The homozygotes for -794(CATT)5–8 and -173G/C polymorphisms were obtained
to estimate the haplotype frequencies. Significantly higher haplotype frequencies were observed for CATT5/G in
controls [global P value=0.044]. Additionally, the CATT5/C and CATT7/G haplotypes were not detected in any groups.
Expression level of mRNA in ectopic tissue of endometriosis patients with CATT6,7/CC haplotype, were significantly
higher compared to other haplotypes including CATT5,5/GG (2.91 fold, P=0.007), CATT5,5/GC (2.48 fold, P=0.047) and
CATT6,6/GG (2.08 fold, P=0.046).
Conclusion We report, for the first time, a strong linkage between the decreased repetition of CATT and G allele
in control and CATT6/C and CATT7/C haplotypes in endometriosis patients. Increased MIF expression is affected by
genetic variants in the MIF promoter in ectopic endometrial tissues. This promoter haplotype might play an important
role in the development and establishment of endometriosis.
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Affiliation(s)
- Zahra Chekini
- Department of Biology, Science and Research Branch, Islamic Azad University, Tehran, Iran.,Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Maryam Shahhoseini
- Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.,Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Reza Aflatoonian
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran. Electronic Address:
| | - Parvaneh Afsharian
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran. Electronic Address:
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7
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Chekini Z, Poursadoughian Yaran A, Ansari-Pour N, Shahhoseini M, Ramazanali F, Aflatoonian R, Afsharian P. A novel gene-wide haplotype at the macrophage migration inhibitory factor (MIF) locus is associated with endometrioma. Eur J Obstet Gynecol Reprod Biol 2019; 247:6-9. [PMID: 32044623 DOI: 10.1016/j.ejogrb.2019.12.028] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2019] [Revised: 12/16/2019] [Accepted: 12/23/2019] [Indexed: 02/01/2023]
Abstract
OBJECTIVE Endometriosis is a common complex gynecological disorder that may result in infertility. Macrophage migration inhibitory factor (MIF) is a key pro-inflammatory cytokine that is overexpressed in endometriosis tissues. However, hitherto, no study tested the possible relevancy at genetic level. The aim of this study was to evaluate MIF polymorphisms and possible associations between haplotype of the gene and endometrioma. STUDY DESIGN In this experiment, 115 patients with confirmed endometrioma and 120 of women who were not diagnosed with endometrioma were recruited for this case-control genetic association study. The coding region of MIF was resequenced to detect variations of potential significance. Restriction fragment length polymorphism was used to type the -173 G/C (rs755622) promoter Single nucleotide polymorphism (SNP). Haplotype analyses were then undertaken to assess the effect of genetic variations. RESULTS We detected one functional SNP in promoter (rs755622) and non-functional mutations across the gene including (rs2096525, rs182012324, rs33958703 and rs2070766) in our samples. However, haplotype analysis showed a significant association between MIF and endometrioma where a single haplotype CC carrying only the minor allele at -173 G/C was significantly over-represented in the patients group (P = 0.007) and remained significant even after correction for (Bonferroni adjusted P = 0.028). CONCLUSION We report a strong linkage between a novel MIF haplotype and endometrioma. This association is consistent with expression data at both transcript and protein levels suggesting the -173C/G promoter as a critical factor.
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Affiliation(s)
- Zahra Chekini
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran; Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Atiyeh Poursadoughian Yaran
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Naser Ansari-Pour
- Big Data Institute, Nuffield Department of Medicine, University of Oxford, Oxford, OX3 7LF, United Kingdom
| | - Maryam Shahhoseini
- Reproductive Epidemiology Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Fariba Ramazanali
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran
| | - Reza Aflatoonian
- Department of Endocrinology and Female Infertility, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.
| | - Parvaneh Afsharian
- Department of Genetics, Reproductive Biomedicine Research Center, Royan Institute for Reproductive Biomedicine, ACECR, Tehran, Iran.
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Erdős E, Bálint BL. COUP-TFII is a modulator of cell-type-specific genetic programs based on genomic localization maps. J Biotechnol 2019; 301:11-17. [DOI: 10.1016/j.jbiotec.2019.05.305] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2019] [Revised: 05/16/2019] [Accepted: 05/28/2019] [Indexed: 01/04/2023]
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Ó'Léime CS, Hoban AE, Hueston CM, Stilling R, Moloney G, Cryan JF, Nolan YM. The orphan nuclear receptor TLX regulates hippocampal transcriptome changes induced by IL-1β. Brain Behav Immun 2018. [PMID: 29518529 DOI: 10.1016/j.bbi.2018.03.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
TLX is an orphan nuclear receptor highly expressed within neural progenitor cells (NPCs) in the hippocampus where is regulates proliferation. Inflammation has been shown to have negative effects on hippocampal function as well as on NPC proliferation. Specifically, the pro-inflammatory cytokine IL-1β suppresses NPC proliferation as well as TLX expression in the hippocampus. However, it is unknown whether TLX itself is involved in regulating the inflammatory response in the hippocampus. To explore the role of TLX in inflammation, we assessed changes in the transcriptional landscape of the hippocampus of TLX knockout mice (TLX-/-) compared to wildtype (WT) littermate controls with and without intrahippocampal injection of IL-1β using a whole transcriptome RNA sequencing approach. We demonstrated that there is an increase in the transcription of genes involved in the promotion of inflammation and regulation of cell chemotaxis (Tnf, Il1b, Cxcr1, Cxcr2, Tlr4) and a decrease in the expression of genes relating to synaptic signalling (Lypd1, Syt4, Cplx2) in cannulated TLX-/- mice compared to WT controls. We demonstrate that mice lacking in TLX share a similar increase in 176 genes involved in regulating inflammation (e.g. Cxcl1, Tnf, Il1b) as WT mice injected with IL-1β into the hippocampus. Moreover, TLX-/- mice injected with IL-1β displayed a blunted transcriptional profile compared to WT mice injected with IL-1β. Thus, TLX-/- mice, which already have an exaggerated inflammatory profile after cannulation surgery, are primed to respond differently to an inflammatory stimulus such as IL-1β. Together, these results demonstrate that TLX regulates hippocampal inflammatory transcriptome response to brain injury (in this case cannulation surgery) and cytokine stimulation.
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Affiliation(s)
- Ciarán S Ó'Léime
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Alan E Hoban
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Cara M Hueston
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - Roman Stilling
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Gerard Moloney
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland
| | - John F Cryan
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland
| | - Yvonne M Nolan
- Department of Anatomy and Neuroscience, University College Cork, Cork, Ireland; APC Microbiome Institute, University College Cork, Cork, Ireland.
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Identification and characterization of transcriptional control region of the human beta 1,4-mannosyltransferase gene. Cytotechnology 2015; 69:417-434. [PMID: 26608959 DOI: 10.1007/s10616-015-9929-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2015] [Accepted: 11/02/2015] [Indexed: 10/22/2022] Open
Abstract
All asparagine-linked glycans (N-glycans) on the eukaryotic glycoproteins are primarily derived from dolichol-linked oligosaccharides (DLO), synthesized on the rough endoplasmic reticulum membrane. We have previously reported cloning and identification of the human gene, HMT-1, which encodes chitobiosyldiphosphodolichol beta-mannosyltransferase (β1,4-MT) involved in the early assembly of DLO. Considering that N-glycosylation is one of the most ubiquitous post-translational modifications for many eukaryotic proteins, the HMT-1 could be postulated as one of the housekeeping genes, but its transcriptional regulation remains to be investigated. Here we screened a 1 kb region upstream from HMT-1 open reading frame (ORF) for transcriptionally regulatory sequences by using chloramphenicol acetyl transferase (CAT) assay, and found that the region from -33 to -1 positions might act in HMT-1 transcription at basal level and that the region from -200 to -42 should regulate its transcription either positively or negatively. In addition, results with CAT assays suggested the possibility that two GATA-1 motifs and an Sp1 motif within a 200 bp region upstream from HMT-1 ORF might significantly upregulate HMT-1 transcription. On the contrary, the observations obtained from site-directed mutational analyses revealed that an NF-1/AP-2 overlapping motif located at -148 to -134 positions should serve as a strong silencer. The control of the HMT-1 transcription by these motifs resided within the 200 bp region could partially explain the variation of expression level among various human tissues, suggesting availability and importance of this region for regulatory role in HMT-1 expression.
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Róna G, Borsos M, Ellis JJ, Mehdi AM, Christie M, Környei Z, Neubrandt M, Tóth J, Bozóky Z, Buday L, Madarász E, Bodén M, Kobe B, Vértessy BG. Dynamics of re-constitution of the human nuclear proteome after cell division is regulated by NLS-adjacent phosphorylation. Cell Cycle 2015; 13:3551-64. [PMID: 25483092 DOI: 10.4161/15384101.2014.960740] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Phosphorylation by the cyclin-dependent kinase 1 (Cdk1) adjacent to nuclear localization signals (NLSs) is an important mechanism of regulation of nucleocytoplasmic transport. However, no systematic survey has yet been performed in human cells to analyze this regulatory process, and the corresponding cell-cycle dynamics have not yet been investigated. Here, we focused on the human proteome and found that numerous proteins, previously not identified in this context, are associated with Cdk1-dependent phosphorylation sites adjacent to their NLSs. Interestingly, these proteins are involved in key regulatory events of DNA repair, epigenetics, or RNA editing and splicing. This finding indicates that cell-cycle dependent events of genome editing and gene expression profiling may be controlled by nucleocytoplasmic trafficking. For in-depth investigations, we selected a number of these proteins and analyzed how point mutations, expected to modify the phosphorylation ability of the NLS segments, perturb nucleocytoplasmic localization. In each case, we found that mutations mimicking hyper-phosphorylation abolish nuclear import processes. To understand the mechanism underlying these phenomena, we performed a video microscopy-based kinetic analysis to obtain information on cell-cycle dynamics on a model protein, dUTPase. We show that the NLS-adjacent phosphorylation by Cdk1 of human dUTPase, an enzyme essential for genomic integrity, results in dynamic cell cycle-dependent distribution of the protein. Non-phosphorylatable mutants have drastically altered protein re-import characteristics into the nucleus during the G1 phase. Our results suggest a dynamic Cdk1-driven mechanism of regulation of the nuclear proteome composition during the cell cycle.
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Key Words
- Cdc28, cyclin-dependent protein kinase (Cdk) encoded by CDC28
- Cdk1, cyclin-dependent kinase 1
- GO, gene ontology
- NES, nuclear export signal
- NLS, nuclear localization signal
- SNP, single nucleotide polymorphisms
- SV40, Simian virus 40
- UBA1, Ubiquitin-activating enzyme E1
- UNG2, Human Uracil-DNA glycosylase 2
- cNLS, classical nuclear localization signal
- cell cycle
- dNTP, deoxyribonucleotide triphosphate
- dTTP, deoxythymidine triphosphate
- dUMP, deoxyuridine monophosphate
- dUTP, deoxyuridine triphosphate
- dUTPase
- importin
- phosphorylation
- trafficking
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Affiliation(s)
- Gergely Róna
- a Institute of Enzymology; RCNS; Hungarian Academy of Sciences ; Budapest , Hungary
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Chen S, Chiu SK. AP4 activates cell migration and EMT mediated by p53 in MDA-MB-231 breast carcinoma cells. Mol Cell Biochem 2015; 407:57-68. [PMID: 26037074 DOI: 10.1007/s11010-015-2454-7] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2015] [Accepted: 05/16/2015] [Indexed: 11/25/2022]
Abstract
Tumor metastasis is the primary cause of mortality in most cancer patients. Before disassociation from the tumors, most of malignant tumor cells undergo the epithelial-mesenchymal transition to break away from the adhesions between the cells and the surrounding extracellular matrix. Recently, activating enhancer-binding protein (AP4) has been shown to be a mediator of EMT in colorectal cancer and high level of AP4 correlates with poor prognosis in cancer patients. It has been found that AP4 upregulates the genes involved in EMT and cell proliferation in colorectal cancer cells and that the aggressive human breast cancer cells MDA-MB-231 are highly metastatic. Therefore, we tested the hypothesis that AP4 may also affect cell migration and EMT in this cell type. Three different assays, including the wound-healing assay, the Boyden chamber assay, and the cell tracking assay, were employed to confirm that AP4 activated both cell migration and invasion. Immunofluorescence staining and Western blot analysis revealed that the cells underwent EMT when AP4 was upregulated. In contrast, overexpression of dominant-negative AP4, lacking the DNA-binding domain, inactivated the DNA-binding ability of endogenous AP4 and led to lower cell motility. Furthermore, we found that AP4 enhanced p53 expression at both transcriptional and translational levels. Knockdown of p53 by siRNA significantly diminished the activation of cell migration by AP4, indicating that AP4 can regulate cell migration via the activity of p53.
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Affiliation(s)
- Shaopeng Chen
- Department of Biomedical Sciences, City University of Hong Kong, Tat Chee Avenue, Kowloon Tong, Hong Kong
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13
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Koiwai K, Kubota T, Watanabe N, Hori K, Koiwai O, Masai H. Definition of the transcription factor TdIF1 consensus-binding sequence through genomewide mapping of its binding sites. Genes Cells 2015; 20:242-54. [PMID: 25619743 DOI: 10.1111/gtc.12216] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/12/2014] [Accepted: 12/04/2014] [Indexed: 12/26/2022]
Abstract
TdIF1 was originally identified as a protein that directly binds to terminal deoxynucleotidyltransferase, TdT. Through in vitro selection assays (SELEX), we recently showed that TdIF1 recognizes both AT-tract and a specific DNA sequence motif, 5'-TGCATG-3', and can up-regulate the expression of RAB20 through the latter motif. However, whether TdIF1 binds to these sequences in the cells has not been clear and its other target genes remain to be identified. Here, we determined in vivo TdIF1-binding sequences (TdIF1-invivoBMs) on the human chromosomes through ChIP-seq analyses. The result showed a 160-base pair cassette containing 'AT-tract~palindrome (inverted repeat)~AT-tract' as a likely target sequence of TdIF1. Interestingly, the core sequence of the palindrome in the TdIF1-invivoBMs shares significant similarity to the above 5'-TGCATG-3' motif determined by SELEX in vitro. Furthermore, spacer sequences between AT-tract and the palindrome contain many potential transcription factor binding sites. In luciferase assays, TdIF1 can up-regulate transcription activity of the promoters containing the TdIF1-invivoBM, and this effect is mainly through the palindrome. Clusters of this motif were found in the potential target genes. Gene ontology analysis and RT-qPCR showed the enrichment of some candidate targets of TdIF1 among the genes involved in the regulation of ossification. Potential modes of transcription activation by TdIF1 are discussed.
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Affiliation(s)
- Kotaro Koiwai
- Department of Genome Medicine, Tokyo Metropolitan Institute of Medical Science, Tokyo, 156-8506, Japan
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Scott TL, Rangaswamy S, Wicker CA, Izumi T. Repair of oxidative DNA damage and cancer: recent progress in DNA base excision repair. Antioxid Redox Signal 2014; 20:708-26. [PMID: 23901781 PMCID: PMC3960848 DOI: 10.1089/ars.2013.5529] [Citation(s) in RCA: 107] [Impact Index Per Article: 10.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
SIGNIFICANCE Reactive oxygen species (ROS) are generated by exogenous and environmental genotoxins, but also arise from mitochondria as byproducts of respiration in the body. ROS generate DNA damage of which pathological consequence, including cancer is well established. Research efforts are intense to understand the mechanism of DNA base excision repair, the primary mechanism to protect cells from genotoxicity caused by ROS. RECENT ADVANCES In addition to the notion that oxidative DNA damage causes transformation of cells, recent studies have revealed how the mitochondrial deficiencies and ROS generation alter cell growth during the cancer transformation. CRITICAL ISSUES The emphasis of this review is to highlight the importance of the cellular response to oxidative DNA damage during carcinogenesis. Oxidative DNA damage, including 7,8-dihydro-8-oxoguanine, play an important role during the cellular transformation. It is also becoming apparent that the unusual activity and subcellular distribution of apurinic/apyrimidinic endonuclease 1, an essential DNA repair factor/redox sensor, affect cancer malignancy by increasing cellular resistance to oxidative stress and by positively influencing cell proliferation. FUTURE DIRECTIONS Technological advancement in cancer cell biology and genetics has enabled us to monitor the detailed DNA repair activities in the microenvironment. Precise understanding of the intracellular activities of DNA repair proteins for oxidative DNA damage should provide help in understanding how mitochondria, ROS, DNA damage, and repair influence cancer transformation.
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Affiliation(s)
- Timothy L Scott
- Graduate Center for Toxicology, University of Kentucky , Lexington, Kentucky
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Sengupta S, Mitra S, Bhakat KK. Dual regulatory roles of human AP-endonuclease (APE1/Ref-1) in CDKN1A/p21 expression. PLoS One 2013; 8:e68467. [PMID: 23874636 PMCID: PMC3713036 DOI: 10.1371/journal.pone.0068467] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2013] [Accepted: 05/29/2013] [Indexed: 01/02/2023] Open
Abstract
The human AP-endonuclease (APE1/Ref-1), an essential multifunctional protein involved in repair of oxidative DNA damage as well as in transcriptional regulation, is often overexpressed in tumor cells. APE1 was earlier shown to stimulate p53's DNA binding and its transactivation function in the expression of cyclin-dependent kinase inhibitor p21 (CDKN1A) gene. Here, we show APE1's stable binding to p53 cis elements which are required for p53-mediated activation of p21 in p53-expressing wild type HCT116 cells. However, surprisingly, we observed APE1-dependent repression of p21 in isogenic p53-null HCT116 cells. Ectopic expression of p53 in the p53-null cells abrogated this repression suggesting that APE1's negative regulatory role in p21 expression is dependent on the p53 status. We then identified APE1's another binding site in p21's proximal promoter region containing cis elements for AP4, a repressor of p21. Interestingly, APE1 and AP4 showed mutual dependence for p21 repression. Moreover, ectopic p53 in p53-null cells inhibited AP4's association with APE1, their binding to the promoter and p21 repression. These results together establish APE1's role as a co-activator or co-repressor of p21 gene, dependent on p53 status. It is thus likely that APE1 overexpression and inactivation of p53, often observed in tumor cells, promote tumor cell proliferation by constitutively downregulating p21 expression.
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Affiliation(s)
- Shiladitya Sengupta
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Sankar Mitra
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
| | - Kishor K. Bhakat
- Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, Texas, United States of America
- Sealy Center for Molecular Medicine, University of Texas Medical Branch, Galveston, Texas, United States of America
- * E-mail:
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Jackstadt R, Röh S, Neumann J, Jung P, Hoffmann R, Horst D, Berens C, Bornkamm GW, Kirchner T, Menssen A, Hermeking H. AP4 is a mediator of epithelial-mesenchymal transition and metastasis in colorectal cancer. J Exp Med 2013; 210:1331-50. [PMID: 23752226 PMCID: PMC3698521 DOI: 10.1084/jem.20120812] [Citation(s) in RCA: 122] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2012] [Accepted: 05/20/2013] [Indexed: 12/14/2022] Open
Abstract
The basic helix-loop-helix transcription factor AP4/TFAP4/AP-4 is encoded by a c-MYC target gene and displays up-regulation concomitantly with c-MYC in colorectal cancer (CRC) and numerous other tumor types. Here a genome-wide characterization of AP4 DNA binding and mRNA expression was performed using a combination of microarray, genome-wide chromatin immunoprecipitation, next-generation sequencing, and bioinformatic analyses. Thereby, hundreds of induced and repressed AP4 target genes were identified. Besides many genes involved in the control of proliferation, the AP4 target genes included markers of stemness (LGR5 and CD44) and epithelial-mesenchymal transition (EMT) such as SNAIL, E-cadherin/CDH1, OCLN, VIM, FN1, and the Claudins 1, 4, and 7. Accordingly, activation of AP4 induced EMT and enhanced migration and invasion of CRC cells. Conversely, down-regulation of AP4 resulted in mesenchymal-epithelial transition and inhibited migration and invasion. In addition, AP4 induction was required for EMT, migration, and invasion caused by ectopic expression of c-MYC. Inhibition of AP4 in CRC cells resulted in decreased lung metastasis in mice. Elevated AP4 expression in primary CRC significantly correlated with liver metastasis and poor patient survival. These findings imply AP4 as a new regulator of EMT that contributes to metastatic processes in CRC and presumably other carcinomas.
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Affiliation(s)
- Rene Jackstadt
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians University of Munich, D-80337 Munich, Germany
| | - Simone Röh
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians University of Munich, D-80337 Munich, Germany
| | - Jens Neumann
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians University of Munich, D-80337 Munich, Germany
| | - Peter Jung
- Institute for Research in Biomedicine, Barcelona Science Park, 08028 Barcelona, Spain
| | - Reinhard Hoffmann
- Institute of Medical Microbiology, Immunology and Hygiene, Technical University of Munich, D-81675 Munich, Germany
| | - David Horst
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians University of Munich, D-80337 Munich, Germany
| | - Christian Berens
- Department of Biology, Friedrich-Alexander University of Erlangen-Nuremberg, D-91058 Erlangen, Germany
| | - Georg W. Bornkamm
- Institute of Clinical Molecular Biology and Tumor Genetics, Helmholtz Center Munich, D-81377 Munich, Germany
| | - Thomas Kirchner
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians University of Munich, D-80337 Munich, Germany
- German Cancer Consortium (DKTK), D-69120 Heidelberg, Germany
- German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
| | - Antje Menssen
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians University of Munich, D-80337 Munich, Germany
- German Cancer Consortium (DKTK), D-69120 Heidelberg, Germany
- German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
| | - Heiko Hermeking
- Experimental and Molecular Pathology, Institute of Pathology, Ludwig-Maximilians University of Munich, D-80337 Munich, Germany
- German Cancer Consortium (DKTK), D-69120 Heidelberg, Germany
- German Cancer Research Center (DKFZ), D-69120 Heidelberg, Germany
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Marcilla M, Albar JP. Quantitative proteomics: A strategic ally to map protein interaction networks. IUBMB Life 2013; 65:9-16. [PMID: 23281033 DOI: 10.1002/iub.1081] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Accepted: 07/27/2012] [Indexed: 12/12/2022]
Abstract
Many physiological processes are regulated by dynamic protein interaction networks whose characterization provides valuable information on cell biology. Several strategies can be used to analyze protein-protein interactions. Among them, affinity purification combined with mass spectrometry (AP-MS) is arguably the most widely employed technique, not only owing to its high throughput and sensitivity but also because it can answer critical questions such as where, when, and how protein-protein interactions occur. In AP-MS workflows, both the target protein and its interacting partners are isolated before being identified by MS. The main challenge of this approach is to distinguish bona fide binders from background contaminants. This review focuses on the different strategies designed to circumvent this limitation. In this regard, the combination of quantitative proteomics and affinity purification emerges as one of the most powerful, yet relatively simple, strategies to characterize protein-protein interactions.
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Affiliation(s)
- Miguel Marcilla
- Proteomics Unit, Centro Nacional de Biotecnología, CSIC, Madrid, Spain.
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18
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Huang Y, Kesselman D, Kizub D, Guerrero-Preston R, Ratovitski EA. Phospho-ΔNp63α/microRNA feedback regulation in squamous carcinoma cells upon cisplatin exposure. Cell Cycle 2013; 12:684-97. [PMID: 23343772 DOI: 10.4161/cc.23598] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Our previous reports showed that the cisplatin exposure induced the ATM-dependent phosphorylation of ΔNp63a, which is subsequently involved in transcriptional regulation of gene promoters encoding mRNAs and microRNAs in squamous cell carcinoma (SCC) cells upon cisplatin-induced cell death. We showed that phosphorylated (p)-ΔNp63a plays a role in upregulation of pro-apoptotic proteins, while non-p-ΔNp63a is implicated in pro-survival signaling. In contrast to non-p-ΔNp63a, p-ΔNp63a modulated expression of specific microRNAs in SCC cells exposed to cisplatin. These microRNAs were shown to attenuate the expression of several proteins involved in cell death/survival, suggesting the critical role for p-ΔNp63a in regulation of tumor cell resistance to cisplatin. Here, we studied the function of ΔNp63a in transcriptional activation and repression of the specific microRNA promoters whose expression is affected by cisplatin treatment of SCC cells. We quantitatively studied chromatin-associated proteins bound to tumor protein (TP) p63-responsive element, we found that p-ΔNp63a along with certain transcription coactivators (e.g., CARM1, KAT2B, TFAP2A, etc.) necessary to induce gene promoters for microRNAs (630 and 885-3p) or with transcription corepressors (e.g., EZH2, CTBP1, HDACs, etc.) needed to repress promoters for microRNAs (181a-5p, 374a-5p and 519a-3p) in SCC cells exposed to cisplatin.
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Affiliation(s)
- Yiping Huang
- Department of Dermatology, Johns Hopkins University School of Medicine, Baltimore, MD, USA
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19
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Brandl A, Wagner T, Uhlig KM, Knauer SK, Stauber RH, Melchior F, Schneider G, Heinzel T, Krämer OH. Dynamically regulated sumoylation of HDAC2 controls p53 deacetylation and restricts apoptosis following genotoxic stress. J Mol Cell Biol 2012; 4:284-93. [DOI: 10.1093/jmcb/mjs013] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
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20
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Whiffin N, Broderick P, Lubbe SJ, Pittman AM, Penegar S, Chandler I, Houlston RS. MLH1-93G > A is a risk factor for MSI colorectal cancer. Carcinogenesis 2011; 32:1157-61. [PMID: 21565826 DOI: 10.1093/carcin/bgr089] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023] Open
Abstract
The -93G > A (rs1800734) polymorphism within the core promoter region of the MutL homolog 1 (MLH1) gene has recently been proposed as a low penetrance variant for colorectal cancer (CRC). We evaluated the significance of rs1800734 on CRC risk by genotyping 10 409 CRC cases and 6965 controls. The per allele odds ratio (OR) for all CRC-associated MLH1-93G > A was 1.06 (P = 0.037). Using a subset of 3132 cases with known microsatellite instability (MSI) status, the risk was shown to be confined to microsatellite instability-high (MSI-H) CRC; OR = 1.39 (P = 1.45 × 10(-4)). A meta-analysis of our study and four smaller published studies (totalling 801 cases, 10 890 controls) provided for increased evidence of relationship between MLH1-93G > A and MSI-H CRC risk (P = 3.43 × 10(-12)). The impact of MLH1-93G > A on CRC risk was shown to be independent of the 14 low penetrance loci for CRC identified by recent genome-wide association studies. These data provide further evidence that MLH1-93G > A is a low-penetrance variant for CRC and support the proposition that MLH1-93G > A acts as marker for a somatic event defining a specific CRC subtype.
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Affiliation(s)
- Nicola Whiffin
- Section of Cancer Genetics, Institute of Cancer Research, Sutton, UK
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21
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Washburn MP. Driving biochemical discovery with quantitative proteomics. Trends Biochem Sci 2010; 36:170-7. [PMID: 20880711 DOI: 10.1016/j.tibs.2010.09.001] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2010] [Revised: 08/31/2010] [Accepted: 09/01/2010] [Indexed: 11/26/2022]
Abstract
Proteomic analysis of biological samples plays an increasing role in modern research. Although the application of proteomics technologies varies across many disciplines, proteomics largely is a tool for discovery that then leads to novel hypotheses. In recent years, new methods and technologies have been developed and applied in many areas of proteomics, and there is a strong push towards using proteomics in a quantitative manner. Indeed, mass spectrometry-based, quantitative proteomics approaches have been applied to great success in a variety of biochemical studies. In particular, the use of quantitative proteomics provides new insights into protein complexes and post-translational modifications and leads to the generation of novel insights into these important biochemical systems.
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Affiliation(s)
- Michael P Washburn
- Stowers Institute for Medical Research, Kansas City, 1000 E. 50(th) St., MO 64110, USA.
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