The Emerging Roles of the HERC Ubiquitin Ligases in Cancer

Background: The HERC family contains six members from HERC1 to HERC6 that are featured with the HECT domains that exerts ubiquitin ligase activity and the RCC1-like domains that are involved in cell cycle regulation. Although identified as early as 1990s, their biological functions are extensively studied in recent years. More and more researches have demonstrated that the HERC ubiquitin ligases are widely engaged in carcinogenesis, however, there lacks a comprehensive and instructive analysis. Methods: The PubMed database was searched by keywords of individual HERC proteins (such as HERC4) and cancer. The emerging roles of HERC proteins in cancer and the specific mechanisms were collectively analyzed and discussed. Results: HERC proteins belong to the HECT domain-containing ubiquitin ligases that can identify and mediate the ubiquitination of specific substrate proteins. All HERC ubiquitin ligases except HERC6 have been assigned one or more than one ubiquitination substrates. In all of HERCs, HERC1 and HERC2 have been widely studied, in contrast, there are no reported studies yet on protein ubiquitination mediated by HERC6. Dependent on the protein substrates, HERC proteins may act as a tumor suppressor or oncoprotein in specific cancer types. For example, HERC4 is believed to contribute to carcinogenesis of solid tumors such as lung cancer, but it suppresses the proliferation of myeloma cells. Conclusion: HERC proteins as ubiquitin ligases are widely involved in various cancers. Targeting at specific HERC proteins could be a strategy for the treatment of certain cancers.

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Targeting NEDDylation as a Novel Approach to Improve the Treatment of Head and Neck Cancer

Cancers ◽

10.3390/cancers13133250 ◽

2021 ◽

Vol 13 (13) ◽

pp. 3250

Author(s):

Trace M. Jones ◽

Jennifer S. Carew ◽

Julie E. Bauman ◽

Steffan T. Nawrocki

Keyword(s):

Head And Neck Cancer ◽

Head And Neck ◽

Patient Outcomes ◽

Neck Cancer ◽

Cellular Stress Response ◽

Novel Approach ◽

Damage Repair ◽

Cancer Types ◽

Cycle Regulation ◽

Substrate Proteins

Head and neck cancer is diagnosed in nearly 900,000 new patients worldwide each year. Despite this alarming number, patient outcomes, particularly for those diagnosed with late-stage and human papillomavirus (HPV)-negative disease, have only marginally improved in the last three decades. New therapeutics that target novel pathways are desperately needed. NEDDylation is a key cellular process by which NEDD8 proteins are conjugated to substrate proteins in order to modulate their function. NEDDylation is closely tied to appropriate protein degradation, particularly proteins involved in cell cycle regulation, DNA damage repair, and cellular stress response. Components of the NEDDylation pathway are frequently overexpressed or hyperactivated in many cancer types including head and neck cancer, which contribute to disease progression and drug resistance. Therefore, targeting NEDDylation could have a major impact for malignancies with alterations in the pathway, and this has already been demonstrated in preclinical studies and clinical trials. Here, we will survey the mechanisms by which aberrant NEDDylation contributes to disease pathogenesis and discuss the potential clinical implications of inhibiting NEDDylation as a novel approach for the treatment of head and neck cancer.

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Chemotherapy for Late-Stage Cancer Patients: Meta-Analysis of Complete Response Rates

F1000Research ◽

10.12688/f1000research.6760.1 ◽

2015 ◽

Vol 4 ◽

pp. 232 ◽

Cited By ~ 10

Author(s):

Martin L. Ashdown ◽

Andrew P. Robinson ◽

Steven L. Yatomi-Clarke ◽

M. Luisa Ashdown ◽

Andrew Allison ◽

...

Keyword(s):

Cancer Patients ◽

Late Stage ◽

Meta Analysis ◽

Complete Response ◽

Drug Regimen ◽

Cancer Type ◽

Late Stage Cancer ◽

Pubmed Database ◽

Wide Range ◽

Cancer Types

Complete response (CR) rates reported for cytotoxic chemotherapy for late-stage cancer patients are generally low, with few exceptions, regardless of the solid cancer type or drug regimen. We investigated CR rates reported in the literature for clinical trials using chemotherapy alone, across a wide range of tumour types and chemotherapeutic regimens, to determine an overall CR rate for late-stage cancers. A total of 141 reports were located using the PubMed database. A meta-analysis was performed of reported CR from 68 chemotherapy trials (total 2732 patients) using standard agents across late-stage solid cancers—a binomial model with random effects was adopted. Mean CR rates were compared for different cancer types, and for chemotherapeutic agents with different mechanisms of action, using a logistic regression. Our results showed that the CR rates for chemotherapy treatment of late-stage cancer were generally low at 7.4%, regardless of the cancer type or drug regimen used. We found no evidence that CR rates differed between different chemotherapy drug types, but amongst different cancer types small CR differences were evident, although none exceeded a mean CR rate of 11%. This remarkable concordance of CR rates regardless of cancer or therapy type remains currently unexplained, and motivates further investigation.

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Development of potential inhibitors of cell division protein kinase 2 by ligand based drug design

Main Group Chemistry ◽

10.3233/mgc-210013 ◽

2021 ◽

pp. 1-10

Author(s):

Vildan Enisoğlu Atalay ◽

Büşra Savaş

Keyword(s):

Hydrogen Bond ◽

Cell Division ◽

Drug Design ◽

Discovery Studio ◽

Cyclin Dependent Kinases ◽

Hydrogen Bond Interactions ◽

Damage Repair ◽

Cancer Types ◽

Potential Inhibitors ◽

Cycle Regulation

Cyclin-dependent kinases (CDKs) are commonly known by their role in cell cycle regulation which affects cancer mechanism. In many cancer types, CDKs show extreme activity or CDK inhibiting proteins are dysfunctional. Specifically, CDK2 plays an indispensable role in cell division especially in the G1/S phase and DNA damage repair. Therefore, it is important to find new potential CDK2 inhibitors. In this study, ligand-based drug design is used to design new potential CDK2 inhibitors. Y8 L ligand is obtained from the X-ray crystal structure of human CDK2 (PDB ID: 2XNB) (www.pdb.org) and used as a structure model. By adding hydrophilic and hydrophobic groups to the structure, a training set of 36 molecules is generated. Each molecule examined with Spartan’14 and optimized structures are used for docking to CDK2 structure by AutoDock and AutoDock Vina programs. Ligand-amino acid interactions are analysed with Discovery Studio Visualizer. Van der Waals, Pi-Pi T-shaped, alkyl, pi-alkyl, conventional hydrogen bond and carbon-hydrogen bond interactions are observed. By docking results and viewed interactions, some molecules are identified and discussed as potential CDK2 inhibitors. Additionally, 8 different QSAR descriptors obtained from Spartan’14, Preadmet and ALOGPS 2.1 programs are investigated with multiple linear regulation (MLR) analysis with SPSS program for their impact on affinity value.

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N-terminal acetylation of the yeast Derlin Der1 is essential for Hrd1 ubiquitin-ligase activity toward luminal ER substrates

Molecular Biology of the Cell ◽

10.1091/mbc.e12-11-0838 ◽

2013 ◽

Vol 24 (7) ◽

pp. 890-900 ◽

Cited By ~ 31

Author(s):

Dimitrios Zattas ◽

David J. Adle ◽

Eric M. Rubenstein ◽

Mark Hochstrasser

Keyword(s):

Endoplasmic Reticulum ◽

Transcription Factor ◽

Fusion Protein ◽

Protein Degradation ◽

Ubiquitin Ligase ◽

Ubiquitin Ligases ◽

Recent Analysis ◽

Specific Class ◽

Wild Type ◽

Ubiquitin Ligase Activity

Two conserved ubiquitin ligases, Hrd1 and Doa10, mediate most endoplasmic reticulum–associated protein degradation (ERAD) in yeast. Degradation signals (degrons) recognized by these ubiquitin ligases remain poorly characterized. Doa10 recognizes the Deg1 degron from the MATα2 transcription factor. We previously found that deletion of the gene (NAT3) encoding the catalytic subunit of the NatB N-terminal acetyltransferase weakly stabilized a Deg1-fusion protein. By contrast, a recent analysis of several MATα2 derivatives suggested that N-terminal acetylation of these proteins by NatB was crucial for recognition by Doa10. We now analyze endogenous MATα2 degradation in cells lacking NatB and observe minimal perturbation relative to wild-type cells. However, NatB mutation strongly impairs degradation of ER-luminal Hrd1 substrates. This unexpected defect derives from a failure of Der1, a Hrd1 complex subunit, to be N-terminally acetylated in NatB mutant yeast. We retargeted Der1 to another acetyltransferase to show that it is the only ERAD factor requiring N-terminal acetylation. Preventing Der1 acetylation stimulates its proteolysis via the Hrd1 pathway, at least partially accounting for the ERAD defect observed in the absence of NatB. These results reveal an important role for N-terminal acetylation in controlling Hrd1 ligase activity toward a specific class of ERAD substrates.

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Inhibition of O-GlcNAc transferase (OGT) by peptidic hybrids

MedChemComm ◽

10.1039/c8md00115d ◽

2018 ◽

Vol 9 (5) ◽

pp. 883-887 ◽

Cited By ~ 5

Author(s):

Hao Zhang ◽

Tihomir Tomašič ◽

Jie Shi ◽

Matjaž Weiss ◽

Rob Ruijtenbeek ◽

...

Keyword(s):

Specific Substrate ◽

Glcnac Transferase ◽

Substrate Proteins

O-GlcNAc transferase (OGT) attaches a GlcNAc moiety on specific substrate proteins using UDP-GlcNAc as the sugar donor.

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E3 Ubiquitin Ligase TRIM Proteins, Cell Cycle and Mitosis

Cells ◽

10.3390/cells8050510 ◽

2019 ◽

Vol 8 (5) ◽

pp. 510 ◽

Cited By ~ 21

Author(s):

Santina Venuto ◽

Giuseppe Merla

Keyword(s):

Cell Cycle ◽

Cancer Progression ◽

Current Knowledge ◽

Ubiquitin Ligases ◽

Cell Protein ◽

E3 Ubiquitin Ligases ◽

Daughter Cells ◽

Protein Ubiquitination ◽

Functional Units ◽

Trim Proteins

The cell cycle is a series of events by which cellular components are accurately segregated into daughter cells, principally controlled by the oscillating activities of cyclin-dependent kinases (CDKs) and their co-activators. In eukaryotes, DNA replication is confined to a discrete synthesis phase while chromosome segregation occurs during mitosis. During mitosis, the chromosomes are pulled into each of the two daughter cells by the coordination of spindle microtubules, kinetochores, centromeres, and chromatin. These four functional units tie chromosomes to the microtubules, send signals to the cells when the attachment is completed and the division can proceed, and withstand the force generated by pulling the chromosomes to either daughter cell. Protein ubiquitination is a post-translational modification that plays a central role in cellular homeostasis. E3 ubiquitin ligases mediate the transfer of ubiquitin to substrate proteins determining their fate. One of the largest subfamilies of E3 ubiquitin ligases is the family of the tripartite motif (TRIM) proteins, whose dysregulation is associated with a variety of cellular processes and directly involved in human diseases and cancer. In this review we summarize the current knowledge and emerging concepts about TRIMs and their contribution to the correct regulation of cell cycle, describing how TRIMs control the cell cycle transition phases and their involvement in the different functional units of the mitotic process, along with implications in cancer progression.

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EhRho1, a RhoA-Like GTPase of Entamoeba histolytica, Is Modified by Clostridial Glucosylating Cytotoxins

Applied and Environmental Microbiology ◽

10.1128/aem.01826-06 ◽

2006 ◽

Vol 72 (12) ◽

pp. 7842-7848 ◽

Cited By ~ 6

Author(s):

Shubhra Majumder ◽

Gudula Schmidt ◽

Anuradha Lohia ◽

Klaus Aktories

Keyword(s):

Clostridium Difficile ◽

Entamoeba Histolytica ◽

Rho Gtpases ◽

Protozoan Parasite ◽

Alpha Toxin ◽

Toxin B ◽

Protein Substrates ◽

Clostridium Novyi ◽

Substrate Proteins ◽

Mammalian Protein

ABSTRACT Clostridial glucosylating cytotoxins inactivate mammalian Rho GTPases by mono-O glucosylation of a conserved threonine residue located in the switch 1 region of the target protein. Here we report that EhRho1, a RhoA-like GTPase from the protozoan parasite Entamoeba histolytica, is glucosylated by clostridial cytotoxins. Recombinant glutathione S-transferase-EhRho1 and EhRho1 from cell lysate of Entamoeba histolytica were glucosylated by Clostridium difficile toxin B and Clostridium novyi alpha-toxin. In contrast, Clostridium difficile toxin A, which shares the same mammalian protein substrates with toxin B, did not modify EhRho1. Change of threonine 52 of EhRho1 to alanine prevented glucosylation by toxin B from Clostridium difficile and by alpha-toxin from Clostridium novyi, which suggests that the equivalent threonine residues are glucosylated in mammalian and Entamoeba Rho GTPases. Lethal toxin from Clostridium sordellii did not glucosylate EhRho1 but labeled several other substrate proteins in lysates from Entamoeba histolytica in the presence of UDP-[14C]glucose.

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Establishment of a Wheat Cell-Free Synthesized Protein Array Containing 250 Human and Mouse E3 Ubiquitin Ligases to Identify Novel Interaction between E3 Ligases and Substrate Proteins

PLoS ONE ◽

10.1371/journal.pone.0156718 ◽

2016 ◽

Vol 11 (6) ◽

pp. e0156718 ◽

Cited By ~ 21

Author(s):

Hirotaka Takahashi ◽

Atsushi Uematsu ◽

Satoshi Yamanaka ◽

Mei Imamura ◽

Tatsuro Nakajima ◽

...

Keyword(s):

Ubiquitin Ligases ◽

Protein Array ◽

E3 Ubiquitin Ligases ◽

E3 Ligases ◽

Substrate Proteins ◽

Human And Mouse

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Overproduction of Polypeptides Corresponding to the Amino Terminus of the F-Box Proteins Cdc4p and Met30p Inhibits Ubiquitin Ligase Activities of Their SCF Complexes

Eukaryotic Cell ◽

10.1128/ec.2.1.123-133.2003 ◽

2003 ◽

Vol 2 (1) ◽

pp. 123-133 ◽

Cited By ~ 17

Author(s):

Cheryl Dixon ◽

Lee Ellen Brunson ◽

Mary Margaret Roy ◽

Dechelle Smothers ◽

Michael G. Sehorn ◽

...

Keyword(s):

Ubiquitin Ligase ◽

Ubiquitin Ligases ◽

Cellular Responses ◽

Amino Terminus ◽

Variable Component ◽

Amino Terminal ◽

F Box Protein ◽

Substrate Proteins

ABSTRACT Ubiquitin ligases direct the transfer of ubiquitin onto substrate proteins and thus target the substrate for proteasome-dependent degradation. SCF complexes are a family of ubiquitin ligases composed of a common core of components and a variable component called an F-box protein that defines substrate specificity. Distinct SCF complexes, defined by a particular F-box protein, target different substrate proteins for degradation. Although a few have been identified to be involved in important biological pathways, such as the cell division cycle and coordinating cellular responses to changes in environmental conditions, the role of the overwhelming majority of F-box proteins is not clear. Creating inhibitors that will block the in vivo activities of specific SCF ubiquitin ligases may provide identification of substrates of these uncharacterized F-box proteins. Using Saccharomyces cerevisiae as a model system, we demonstrate that overproduction of polypeptides corresponding to the amino terminus of the F-box proteins Cdc4p and Met30p results in specific inhibition of their SCF complexes. Analyses of mutant amino-terminal alleles demonstrate that the interaction of these polypeptides with their full-length counterparts is an important step in the inhibitory process. These results suggest a common means to inhibit specific SCF complexes in vivo.

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The Ubiquitin Ligase Triad1 Is Involved in Myelopoiesis and Interacts with the Transcriptional Repressors Gfi1 and Gfi1b.

Blood ◽

10.1182/blood.v104.11.64.64 ◽

2004 ◽

Vol 104 (11) ◽

pp. 64-64 ◽

Cited By ~ 9

Author(s):

Bert A. Van der Reijden ◽

Jurgen A.F. Marteijn ◽

Liesbeth Van Emst ◽

Theo De Witte ◽

Joop H. Jansen

Keyword(s):

Bone Marrow ◽

Zinc Finger ◽

Colony Formation ◽

Bone Marrow Cells ◽

26S Proteasome ◽

Specific Substrate ◽

Granulocytic Differentiation ◽

Substrate Proteins ◽

Zinc Finger Region ◽

Marrow Cells

Abstract We identified Triad1 as a gene that is upregulated by retinoic acid during the granulocytic differentiation of acute promyelocytic leukemia cells. In normal hematopoiesis, we show that Triad1 is weakly expressed in immature CD34+ bone marrow cells, and highly expressed in mature monocytes and granulocytes. Together, this suggests that Triad1 plays a role in the differentiation of hematopoietic cells. Triad1 contains a tripartite domain including two RING fingers, indicating that this protein might function as a ubiquitin E3 ligase, catalyzing the the conjugation of ubiquitin to substrate proteins thereby marking them for targeted degradation by the 26S proteasome. Using GST pull down experiments, we show that Triad1 binds to the ubiquitin conjugating (E2) enzymes UbcH6 and 7. In addition, immunoprecipitation of Triad1 in cells that were transfected with FLAG-tagged ubiquitin shows that Triad1 binds to ubiquitinated proteins, and that Triad1 is capable of self-ubiquitination, further corroborating the assumption that Triad1 acts as a E3 ubiquitin ligating enzyme. To study the role of Triad1 in hematopoiesis we overexpressed the gene in primary murine bone marrow cells using a retroviral vector that contains Triad1 in front of an IRES-GFP cassette. GFP positive cells were FACS sorted and used in colony assays (CFU-GM). Compared to empty vector controls (GFP alone), Triad1 expression resulted in more than 80% inhibition of clonogenic growth. Importantly, addition of the proteasome inhibitor MG132 (10E-8 M) reversed the Triad1-induced suppression of colony formation. Furthermore, three Triad1 expression constructs in which one of the conserved cys/his residues of the TRIAD domain (essential for function) were mutated did not show the suppressive effect on colony formation. Together, these data show that Triad1 is involved in myelopoiesis and acts through the ubiquitination of specific substrate proteins. To identify these substrates, a yeast-two-hybrid screen of a human bone marrow cDNA library was performed using the Triad1 protein as a bait. Interestingly, the transcriptional repressor Gfi1b was found to bind to Triad1. The interaction was confirmed by immunoprecipitation using GFP-Triad1 and FLAG-tagged Gfi1b transfections in mammalian cells. We show that Triad1 binds to the zinc finger region of Gfi1b. This region is very (>98%) homologous to the paralogue Gfi1. Further immunoprecipitation analyses showed that Triad1 also binds to the zinc finger region of Gfi1. Gfi1 plays an essential role in neutrophil development and Gfi1 pointmutations result in neutropenia in man. Currently, we are studying the direct ubiquitination of Gfi and Gfi1b by Triad1 in in vitro ubiquitination assays. In addition, we are studying the effect of Triad1 on the transcriptional repression of the ELA2 and other promoters by Gfi1.

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