1
|
Danagulyan GG, Panosyan HA, Gharibyan VK, Hasratyan AH. A Simple and Easily Implemented Method for the Regioselective Introduction of Deuterium into Azolo[1,5- a]pyrimidines Molecules. Molecules 2023; 28:molecules28062869. [PMID: 36985841 PMCID: PMC10054722 DOI: 10.3390/molecules28062869] [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: 02/09/2023] [Revised: 03/16/2023] [Accepted: 03/17/2023] [Indexed: 03/30/2023] Open
Abstract
A method for the technically easy-to-implement synthesis of deuterium-labeled pyrazolo[1,5-a]pyrimidines and 1,2,4-triazolo[1,5-a]pyrimidines have been developed. The regioselectivity of such transformations has been shown. 1H NMR and mass spectrometric methods have proved the quantitative nature of such transformations and the kinetics of deuterium exchange has been studied. Spectrally, at different temperatures (+30 °C, -10 °C and -15 °C), the kinetics of the process was studied both in CD3OD and in deuterated alkali.
Collapse
Affiliation(s)
- Gevorg G Danagulyan
- Laboratory of Bioactive Azaheterocycles, Institute of Biomedicine and Pharmacy, Russian-Armenian University, Hovsep Emin Str. 123, Yerevan 0051, Armenia
- Scientific and Technological Center of Organic and Pharmaceutical Chemistry, The National Academy of Sciences of the Republic of Armenia, Azatutyan Ave. 26, Yerevan 0014, Armenia
| | - Henrik A Panosyan
- Scientific and Technological Center of Organic and Pharmaceutical Chemistry, The National Academy of Sciences of the Republic of Armenia, Azatutyan Ave. 26, Yerevan 0014, Armenia
| | - Vache K Gharibyan
- Laboratory of Bioactive Azaheterocycles, Institute of Biomedicine and Pharmacy, Russian-Armenian University, Hovsep Emin Str. 123, Yerevan 0051, Armenia
| | - Ani H Hasratyan
- Laboratory of Bioactive Azaheterocycles, Institute of Biomedicine and Pharmacy, Russian-Armenian University, Hovsep Emin Str. 123, Yerevan 0051, Armenia
- Scientific and Technological Center of Organic and Pharmaceutical Chemistry, The National Academy of Sciences of the Republic of Armenia, Azatutyan Ave. 26, Yerevan 0014, Armenia
| |
Collapse
|
2
|
Sohn J, Lee SE, Shim EY. DNA Damage and Repair in Eye Diseases. Int J Mol Sci 2023; 24:3916. [PMID: 36835325 PMCID: PMC9964121 DOI: 10.3390/ijms24043916] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Revised: 01/30/2023] [Accepted: 02/02/2023] [Indexed: 02/17/2023] Open
Abstract
Vision is vital for daily activities, and yet the most common eye diseases-cataracts, DR, ARMD, and glaucoma-lead to blindness in aging eyes. Cataract surgery is one of the most frequently performed surgeries, and the outcome is typically excellent if there is no concomitant pathology present in the visual pathway. In contrast, patients with DR, ARMD and glaucoma often develop significant visual impairment. These often-multifactorial eye problems can have genetic and hereditary components, with recent data supporting the role of DNA damage and repair as significant pathogenic factors. In this article, we discuss the role of DNA damage and the repair deficit in the development of DR, ARMD and glaucoma.
Collapse
Affiliation(s)
- Joanna Sohn
- Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
- Keystone School, 119 E. Craig Pl., San Antonio, TX 78212, USA
| | - Sang-Eun Lee
- Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
| | - Eun-Yong Shim
- Department of Molecular Medicine, The University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA
| |
Collapse
|
3
|
Saccharomyces cerevisiae as a Model System for Eukaryotic Cell Biology, from Cell Cycle Control to DNA Damage Response. Int J Mol Sci 2022; 23:ijms231911665. [PMID: 36232965 PMCID: PMC9570374 DOI: 10.3390/ijms231911665] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/23/2022] [Revised: 09/26/2022] [Accepted: 09/28/2022] [Indexed: 11/08/2022] Open
Abstract
The yeast Saccharomyces cerevisiae has been used for bread making and beer brewing for thousands of years. In addition, its ease of manipulation, well-annotated genome, expansive molecular toolbox, and its strong conservation of basic eukaryotic biology also make it a prime model for eukaryotic cell biology and genetics. In this review, we discuss the characteristics that made yeast such an extensively used model organism and specifically focus on the DNA damage response pathway as a prime example of how research in S. cerevisiae helped elucidate a highly conserved biological process. In addition, we also highlight differences in the DNA damage response of S. cerevisiae and humans and discuss the challenges of using S. cerevisiae as a model system.
Collapse
|
4
|
Liu H, Yang M, Dong Z. HSPB11 is a Prognostic Biomarker Associated with Immune Infiltrates in Hepatocellular Carcinoma. Int J Gen Med 2022; 15:4017-4027. [PMID: 35444459 PMCID: PMC9014112 DOI: 10.2147/ijgm.s363679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2022] [Accepted: 04/05/2022] [Indexed: 12/24/2022] Open
Abstract
Purpose Patients and Methods Results Conclusion
Collapse
Affiliation(s)
- Hui Liu
- Department of Gastroenterology, Second Hospital of Dalian Medical University, Dalian, Liaoning, People’s Republic of China
| | - Mei Yang
- Department of Gastroenterology, Second Hospital of Dalian Medical University, Dalian, Liaoning, People’s Republic of China
| | - Zhiwei Dong
- Department of General Surgery, Air Force Medical Center, PLA, Beijing, People’s Republic of China
- Correspondence: Zhiwei Dong, Department of General Surgery, Air Force Medical Center, PLA, Beijing, People’s Republic of China, Tel +8617611408626, Fax +86 411-84671291-3106, Email
| |
Collapse
|
5
|
Kordestani N, Abas E, Grasa L, Alguacil A, Scalambra F, Romerosa A. The Significant Influence of a Second Metal on the Antiproliferative Properties of the Complex [Ru(η 6 -C 10 H 14 )(Cl 2 )(dmoPTA)]. Chemistry 2021; 28:e202103048. [PMID: 34806242 PMCID: PMC9299940 DOI: 10.1002/chem.202103048] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2021] [Indexed: 12/16/2022]
Abstract
Complexes [Ru(η6−C10H14)(Cl2)(HdmoPTA)](OSO2CF3) (1), [Ru(η6−C10H14)(Cl2)(dmoPTA)] (2) and [Ru(η6−C10H14)(Cl2)‐μ‐dmoPTA‐1κP:2κ2N,N’‐MCl2] (M=Zn (3), Co (4), Ni (5), dmoPTA=3,7‐dimethyl‐1,3,7‐triaza‐5‐phosphabicyclo[3.3.1]nonane) have been synthesized and characterized by elemental analysis and spectroscopic techniques. The crystal structures of 1, 3 and 5 were obtained by single‐crystal X‐ray diffraction. The antiproliferative activity of the complexes was evaluated against colon cancer cell line Caco‐2/TC7 by using the MTT protocol. The monometallic ruthenium complexes 1 and 2 were found to be inactive, but the bimetallic complexes 3, 4 and 5 display an increased activity (IC503: 9.07±0.27, 4: 5.40±0.19, 5: 7.15±0.30 μM) compared to cisplatin (IC50=45.6±8.08 μM). Importantly, no reduction in normal cell viability was observed in the presence of the complexes. Experiments targeted to obtain information on the possible action mechanism of the complexes, such as cell cycle, ROS and gene expression studies, were performed. The results showed that the complexes display different properties and action mechanism depending on the nature of metal, M, bonded to the CH3NdmoPTA atoms.
Collapse
Affiliation(s)
- Nazanin Kordestani
- Área de Química Inorgánica-CIESOL Facultad de CienciasUniversidad de AlmeríaCarr. Sacramento, s/n04120La Cañada, AlmeríaSpain
| | - Elisa Abas
- Departamento de Farmacología, Fisiología y Medicina Legal y Forense Facultad de VeterinariaUniversidad de ZaragozaMiguel Servet, 17750013ZaragozaSpain
| | - Laura Grasa
- Departamento de Farmacología, Fisiología y Medicina Legal y Forense Facultad de VeterinariaUniversidad de ZaragozaMiguel Servet, 17750013ZaragozaSpain
- Instituto de Investigación Sanitaria de Aragón (IIS Aragón)San Juan Bosco, 1350009ZaragozaSpain
- Instituto Agroalimentario de Aragón -IA2-Universidad de Zaragoza–CITA)Miguel Servet, 17750013ZaragozaSpain
| | - Andres Alguacil
- Área de Química Inorgánica-CIESOL Facultad de CienciasUniversidad de AlmeríaCarr. Sacramento, s/n04120La Cañada, AlmeríaSpain
| | - Franco Scalambra
- Área de Química Inorgánica-CIESOL Facultad de CienciasUniversidad de AlmeríaCarr. Sacramento, s/n04120La Cañada, AlmeríaSpain
| | - Antonio Romerosa
- Área de Química Inorgánica-CIESOL Facultad de CienciasUniversidad de AlmeríaCarr. Sacramento, s/n04120La Cañada, AlmeríaSpain
| |
Collapse
|
6
|
Tenan MR, Nicolle A, Moralli D, Verbouwe E, Jankowska JD, Durin MA, Green CM, Mandriota SJ, Sappino AP. Aluminum Enters Mammalian Cells and Destabilizes Chromosome Structure and Number. Int J Mol Sci 2021; 22:ijms22179515. [PMID: 34502420 PMCID: PMC8431747 DOI: 10.3390/ijms22179515] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 08/20/2021] [Accepted: 08/26/2021] [Indexed: 12/28/2022] Open
Abstract
Chromosome instability (CIN) consists of high rates of structural and numerical chromosome abnormalities and is a well-known hallmark of cancer. Aluminum is added to many industrial products of frequent use. Yet, it has no known physiological role and is a suspected human carcinogen. Here, we show that V79 cells, a well-established model for the evaluation of candidate chemical carcinogens in regulatory toxicology, when cultured in presence of aluminum—in the form of aluminum chloride (AlCl3) and at concentrations in the range of those measured in human tissues—incorporate the metal in a dose-dependent manner, predominantly accumulating it in the perinuclear region. Intracellular aluminum accumulation rapidly leads to a dose-dependent increase in DNA double strand breaks (DSB), in chromosome numerical abnormalities (aneuploidy) and to proliferation arrest in the G2/M phase of the cell cycle. During mitosis, V79 cells exposed to aluminum assemble abnormal multipolar mitotic spindles and appear to cluster supernumerary centrosomes, possibly explaining why they accumulate chromosome segregation errors and damage. We postulate that chronic aluminum absorption favors CIN in mammalian cells, thus promoting carcinogenesis.
Collapse
Affiliation(s)
- Mirna R. Tenan
- Laboratoire de Cancérogenèse Environnementale, Fondation des Grangettes, 1224 Chêne-Bougeries, Switzerland; (A.N.); (E.V.); (S.J.M.); (A.-P.S.)
- Correspondence: ; Tel.: +41-22-3050480
| | - Adeline Nicolle
- Laboratoire de Cancérogenèse Environnementale, Fondation des Grangettes, 1224 Chêne-Bougeries, Switzerland; (A.N.); (E.V.); (S.J.M.); (A.-P.S.)
| | - Daniela Moralli
- Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (D.M.); (J.D.J.); (M.-A.D.); (C.M.G.)
| | - Emeline Verbouwe
- Laboratoire de Cancérogenèse Environnementale, Fondation des Grangettes, 1224 Chêne-Bougeries, Switzerland; (A.N.); (E.V.); (S.J.M.); (A.-P.S.)
| | - Julia D. Jankowska
- Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (D.M.); (J.D.J.); (M.-A.D.); (C.M.G.)
| | - Mary-Anne Durin
- Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (D.M.); (J.D.J.); (M.-A.D.); (C.M.G.)
| | - Catherine M. Green
- Wellcome Centre for Human Genetics, University of Oxford, Oxford OX3 7BN, UK; (D.M.); (J.D.J.); (M.-A.D.); (C.M.G.)
| | - Stefano J. Mandriota
- Laboratoire de Cancérogenèse Environnementale, Fondation des Grangettes, 1224 Chêne-Bougeries, Switzerland; (A.N.); (E.V.); (S.J.M.); (A.-P.S.)
| | - André-Pascal Sappino
- Laboratoire de Cancérogenèse Environnementale, Fondation des Grangettes, 1224 Chêne-Bougeries, Switzerland; (A.N.); (E.V.); (S.J.M.); (A.-P.S.)
| |
Collapse
|
7
|
Shao Y, Saredy J, Xu K, Sun Y, Saaoud F, Drummer C, Lu Y, Luo JJ, Lopez-Pastrana J, Choi ET, Jiang X, Wang H, Yang X. Endothelial Immunity Trained by Coronavirus Infections, DAMP Stimulations and Regulated by Anti-Oxidant NRF2 May Contribute to Inflammations, Myelopoiesis, COVID-19 Cytokine Storms and Thromboembolism. Front Immunol 2021; 12:653110. [PMID: 34248940 PMCID: PMC8269631 DOI: 10.3389/fimmu.2021.653110] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Accepted: 05/12/2021] [Indexed: 12/13/2022] Open
Abstract
To characterize transcriptomic changes in endothelial cells (ECs) infected by coronaviruses, and stimulated by DAMPs, the expressions of 1311 innate immune regulatomic genes (IGs) were examined in 28 EC microarray datasets with 7 monocyte datasets as controls. We made the following findings: The majority of IGs are upregulated in the first 12 hours post-infection (PI), and maintained until 48 hours PI in human microvascular EC infected by middle east respiratory syndrome-coronavirus (MERS-CoV) (an EC model for COVID-19). The expressions of IGs are modulated in 21 human EC transcriptomic datasets by various PAMPs/DAMPs, including LPS, LPC, shear stress, hyperlipidemia and oxLDL. Upregulation of many IGs such as nucleic acid sensors are shared between ECs infected by MERS-CoV and those stimulated by PAMPs and DAMPs. Human heart EC and mouse aortic EC express all four types of coronavirus receptors such as ANPEP, CEACAM1, ACE2, DPP4 and virus entry facilitator TMPRSS2 (heart EC); most of coronavirus replication-transcription protein complexes are expressed in HMEC, which contribute to viremia, thromboembolism, and cardiovascular comorbidities of COVID-19. ECs have novel trained immunity (TI), in which subsequent inflammation is enhanced. Upregulated proinflammatory cytokines such as TNFα, IL6, CSF1 and CSF3 and TI marker IL-32 as well as TI metabolic enzymes and epigenetic enzymes indicate TI function in HMEC infected by MERS-CoV, which may drive cytokine storms. Upregulated CSF1 and CSF3 demonstrate a novel function of ECs in promoting myelopoiesis. Mechanistically, the ER stress and ROS, together with decreased mitochondrial OXPHOS complexes, facilitate a proinflammatory response and TI. Additionally, an increase of the regulators of mitotic catastrophe cell death, apoptosis, ferroptosis, inflammasomes-driven pyroptosis in ECs infected with MERS-CoV and the upregulation of pro-thrombogenic factors increase thromboembolism potential. Finally, NRF2-suppressed ROS regulate innate immune responses, TI, thrombosis, EC inflammation and death. These transcriptomic results provide novel insights on the roles of ECs in coronavirus infections such as COVID-19, cardiovascular diseases (CVD), inflammation, transplantation, autoimmune disease and cancers.
Collapse
Affiliation(s)
- Ying Shao
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Jason Saredy
- Metabolic Disease Research, Thrombosis Research, Departments of Pharmacology, Microbiology and Immunology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Keman Xu
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Yu Sun
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Fatma Saaoud
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Charles Drummer
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Yifan Lu
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Jin J Luo
- Neurology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Jahaira Lopez-Pastrana
- Psychiatry and Behavioral Science, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Eric T Choi
- Surgery, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Xiaohua Jiang
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States.,Metabolic Disease Research, Thrombosis Research, Departments of Pharmacology, Microbiology and Immunology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Hong Wang
- Metabolic Disease Research, Thrombosis Research, Departments of Pharmacology, Microbiology and Immunology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| | - Xiaofeng Yang
- Centers of Cardiovascular Research, Inflammation, Translational & Clinical Lung Research, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States.,Metabolic Disease Research, Thrombosis Research, Departments of Pharmacology, Microbiology and Immunology, Temple University Lewis Katz School of Medicine, Philadelphia, PA, United States
| |
Collapse
|
8
|
Combined Inactivation of Pocket Proteins and APC/C Cdh1 by Cdk4/6 Controls Recovery from DNA Damage in G1 Phase. Cells 2021; 10:cells10030550. [PMID: 33806417 PMCID: PMC7999910 DOI: 10.3390/cells10030550] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/05/2020] [Revised: 01/29/2021] [Accepted: 02/24/2021] [Indexed: 11/20/2022] Open
Abstract
Most Cyclin-dependent kinases (Cdks) are redundant for normal cell division. Here we tested whether these redundancies are maintained during cell cycle recovery after a DNA damage-induced arrest in G1. Using non-transformed RPE-1 cells, we find that while Cdk4 and Cdk6 act redundantly during normal S-phase entry, they both become essential for S-phase entry after DNA damage in G1. We show that this is due to a greater overall dependency for Cdk4/6 activity, rather than to independent functions of either kinase. In addition, we show that inactivation of pocket proteins is sufficient to overcome the inhibitory effects of complete Cdk4/6 inhibition in otherwise unperturbed cells, but that this cannot revert the effects of Cdk4/6 inhibition in DNA damaged cultures. Indeed, we could confirm that, in addition to inactivation of pocket proteins, Cdh1-dependent anaphase-promoting complex/cyclosome (APC/CCdh1) activity needs to be inhibited to promote S-phase entry in damaged cultures. Collectively, our data indicate that DNA damage in G1 creates a unique situation where high levels of Cdk4/6 activity are required to inactivate pocket proteins and APC/CCdh1 to promote the transition from G1 to S phase.
Collapse
|
9
|
Fidrus E, Hegedűs C, Janka EA, Paragh G, Emri G, Remenyik É. Inhibitors of Nucleotide Excision Repair Decrease UVB-Induced Mutagenesis-An In Vitro Study. Int J Mol Sci 2021; 22:ijms22041638. [PMID: 33562002 PMCID: PMC7915687 DOI: 10.3390/ijms22041638] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 01/31/2021] [Accepted: 02/02/2021] [Indexed: 12/14/2022] Open
Abstract
The high incidence of skin cancers in the Caucasian population is primarily due to the accumulation of DNA damage in epidermal cells induced by chronic ultraviolet B (UVB) exposure. UVB-induced DNA photolesions, including cyclobutane–pyrimidine dimers (CPDs), promote mutations in skin cancer driver genes. In humans, CPDs are repaired by nucleotide excision repair (NER). Several commonly used and investigational medications negatively influence NER in experimental systems. Despite these molecules’ ability to decrease NER activity in vitro, the role of these drugs in enhancing skin cancer risk is unclear. In this study, we investigated four molecules (veliparib, resveratrol, spironolactone, and arsenic trioxide) with well-known NER-inhibitory potential in vitro, using UVB-irradiated CHO epithelial and HaCaT immortalized keratinocyte cell lines. Relative CPD levels, hypoxanthine phosphoribosyltransferase gene mutation frequency, cell viability, cell cycle progression, and protein expression were assessed. All four molecules significantly elevated CPD levels in the genome 24 h after UVB irradiation. However, veliparib, spironolactone, and arsenic trioxide reduced the mutagenic potential of UVB, while resveratrol did not alter UVB-induced mutation formation. UVB-induced apoptosis was enhanced by spironolactone and arsenic-trioxide treatment, while veliparib caused significantly prolonged cell cycle arrest and increased autophagy. Spironolactone also enhanced the phosphorylation level of mammalian target of rapamycin (mTOR), while arsenic trioxide modified UVB-driven mitochondrial fission. Resveratrol induced only mild changes in the cellular UVB response. Our results show that chemically inhibited NER does not result in increased mutagenic effects. Furthermore, the UVB-induced mutagenic potential can be paradoxically mitigated by NER-inhibitor molecules. We identified molecular changes in the cellular UVB response after NER-inhibitor treatment, which may compensate for the mitigated DNA repair. Our findings show that metabolic cellular response pathways are essential to consider in evaluating the skin cancer risk–modifying effects of pharmacological compounds.
Collapse
Affiliation(s)
- Eszter Fidrus
- Department of Dermatology, Faculty of Medicine, University of Debrecen, 98 Nagyerdei Krt, 4032 Debrecen, Hungary; (E.F.); (C.H.); (E.A.J.); (G.E.)
- Doctoral School of Health Sciences, University of Debrecen, 4032 Debrecen, Hungary
| | - Csaba Hegedűs
- Department of Dermatology, Faculty of Medicine, University of Debrecen, 98 Nagyerdei Krt, 4032 Debrecen, Hungary; (E.F.); (C.H.); (E.A.J.); (G.E.)
- Doctoral School of Health Sciences, University of Debrecen, 4032 Debrecen, Hungary
| | - Eszter Anna Janka
- Department of Dermatology, Faculty of Medicine, University of Debrecen, 98 Nagyerdei Krt, 4032 Debrecen, Hungary; (E.F.); (C.H.); (E.A.J.); (G.E.)
| | - György Paragh
- Department of Dermatology, Roswell Park Comprehensive Cancer Center, 665 Elm St, Buffalo, NY 14203, USA;
- Department of Cell Stress Biology, Roswell Park Comprehensive Cancer Center, 665 Elm St, Buffalo, NY 14203, USA
| | - Gabriella Emri
- Department of Dermatology, Faculty of Medicine, University of Debrecen, 98 Nagyerdei Krt, 4032 Debrecen, Hungary; (E.F.); (C.H.); (E.A.J.); (G.E.)
| | - Éva Remenyik
- Department of Dermatology, Faculty of Medicine, University of Debrecen, 98 Nagyerdei Krt, 4032 Debrecen, Hungary; (E.F.); (C.H.); (E.A.J.); (G.E.)
- Correspondence: ; Tel.: +36-52-412-345
| |
Collapse
|
10
|
Rattanapornsompong K, Khattiya J, Phannasil P, Phaonakrop N, Roytrakul S, Jitrapakdee S, Akekawatchai C. Impaired G2/M cell cycle arrest induces apoptosis in pyruvate carboxylase knockdown MDA-MB-231 cells. Biochem Biophys Rep 2021; 25:100903. [PMID: 33490650 PMCID: PMC7806519 DOI: 10.1016/j.bbrep.2020.100903] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Revised: 12/24/2020] [Accepted: 12/25/2020] [Indexed: 11/02/2022] Open
Abstract
Background Previous studies showed that suppression of pyruvate carboxylase (PC) expression in highly invasive breast cancer cell line, MDA-MB-231 inhibits cell growth as a consequence of the impaired cellular biosynthesis. However, the precise cellular mechanism underlying this growth restriction is unknown. Methods We generated the PC knockdown (PCKD) MDA-MB-231 cells and assessed their phenotypic changes by fluorescence microscopy, proliferation, apoptotic, cell cycle assays and proteomics. Results PC knockdown MDA-MB-231 cells had a low percentage of cell viability in association with accumulation of abnormal cells with large or multi-nuclei. Flow cytometric analysis of annexin V-7-AAD positive cells showed that depletion of PC expression triggers apoptosis with the highest rate at day 4. The increased rate of apoptosis is consistent with increased cleavage of procaspase 3 and poly (ADP-Ribose) polymerase. Cell cycle analysis showed that the apoptotic cell death was associated with G2/M arrest, in parallel with marked reduction of cyclin B levels. Proteomic analysis of PCKD cells identified 9 proteins whose expression changes were correlated with the degree of apoptosis and G2/M cell cycle arrest in the PCKD cells. STITCH analysis indicated 3 of 9 candidate proteins, CCT3, CABIN1 and HECTD3, that form interactions with apoptotic and cell cycle signaling networks linking to PC via MgATP. Conclusions Suppression of PC in MDA-MB-231 cells induces G2/M arrest, leading to apoptosis. Proteomic analysis supports the potential involvement of PC expression in the aberrant cell cycle and apoptosis, and identifies candidate proteins responsible for the PC-mediated cell cycle arrest and apoptosis in breast cancer cells. General significance Our results highlight the possibility of the use of PC as an anti-cancer drug target.
Collapse
Affiliation(s)
| | - Janya Khattiya
- Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand.,Graduate Program in Biomedical Sciences, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand
| | - Phatchariya Phannasil
- Thalassemia Research Center, Institute of Molecular Biosciences, Mahidol University, Nakhon-Pathom, Thailand
| | - Narumon Phaonakrop
- Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani, Thailand
| | - Sittiruk Roytrakul
- Functional Ingredients and Food Innovation Research Group, National Center for Genetic Engineering and Biotechnology, National Science and Technology Development Agency, Pathumthani, Thailand
| | - Sarawut Jitrapakdee
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | - Chareeporn Akekawatchai
- Department of Medical Technology, Faculty of Allied Health Sciences, Thammasat University, Pathumthani, Thailand
| |
Collapse
|
11
|
Nathans JF, Cornwell JA, Afifi MM, Paul D, Cappell SD. Cell cycle inertia underlies a bifurcation in cell fates after DNA damage. SCIENCE ADVANCES 2021; 7:7/3/eabe3882. [PMID: 33523889 PMCID: PMC7806216 DOI: 10.1126/sciadv.abe3882] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 11/18/2020] [Indexed: 05/29/2023]
Abstract
The G1-S checkpoint is thought to prevent cells with damaged DNA from entering S phase and replicating their DNA and efficiently arrests cells at the G1-S transition. Here, using time-lapse imaging and single-cell tracking, we instead find that DNA damage leads to highly variable and divergent fate outcomes. Contrary to the textbook model that cells arrest at the G1-S transition, cells triggering the DNA damage checkpoint in G1 phase route back to quiescence, and this cellular rerouting can be initiated at any point in G1 phase. Furthermore, we find that most of the cells receiving damage in G1 phase actually fail to arrest and proceed through the G1-S transition due to persistent cyclin-dependent kinase (CDK) activity in the interval between DNA damage and induction of the CDK inhibitor p21. These observations necessitate a revised model of DNA damage response in G1 phase and indicate that cells have a G1 checkpoint.
Collapse
Affiliation(s)
- Jenny F Nathans
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - James A Cornwell
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Marwa M Afifi
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Debasish Paul
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA
| | - Steven D Cappell
- Laboratory of Cancer Biology and Genetics, Center for Cancer Research, National Cancer Institute, Bethesda, MD, USA.
| |
Collapse
|
12
|
Effect of increasing oxygen partial pressure on Saccharomyces cerevisiae growth and antioxidant and enzyme productions. Appl Microbiol Biotechnol 2020; 104:7815-7826. [PMID: 32789743 DOI: 10.1007/s00253-020-10824-4] [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: 07/07/2020] [Revised: 07/17/2020] [Accepted: 08/10/2020] [Indexed: 10/23/2022]
Abstract
This study investigated the impact of oxygen partial pressure on yeast growth. Saccharomyces cerevisiae cells were exposed to various hyperbaric air conditions from 1 bar to 9 bar absolute pressure (A). Batch cultures were grown under continuous airflow in a 750 mL (500 mL culture) bioreactor and monitored through growth rate and specific yields of ethanol and glycerol. In addition, the concentrations of antioxidant metabolites glutathione (reduced state, GSH and oxidized state, GSSG) and the activity of antioxidative enzymes superoxide dismutases (SOD) and catalases (CAT) were monitored. The results demonstrated that the different oxygen partial pressures significantly impacted the key growth parameters monitored. Compared with atmospheric pressure, under 2 to 5 bar (A), yeast cells showed higher growth rates (μ = 0.32 ± 0.01 h-1) and higher catalase (CAT) concentrations (214 ± 5 mU/g). GSH/GSSG ratio (6.36 ± 0.37) maintained until 6 bar (A) and total SOD (240 ± 5 mU/g) level significantly increased compared with 2 bar (A) until 7 bar (A). Under 6 to 9 bar (A), cell growth was inhibited, and a pressure of 9 bar (A) led to excessive GSSG accumulation (GSH/GSSG = 0.31 ± 0.06). The inhibition of t-SOD (160 ± 3 mU/g) and CAT (62.73 ± 0.2 mU/g) was observed under 9 bar (A). A reference experiment (8 bar (A) N2 + 1 bar (A) air) confirmed that the observed behaviors were entirely due to O2. In addition to their utility in biotechnological process design, these results showed that growth impairment was solely due to oxidative stress induced by excessive oxygen pressure. KEY POINTS: • Yeast cells were grown in batch mode under 1 to 9 bar (A) air pressures and up to 5 bar (A) promoted then hindered growth. • The GSH/GSSG ratio was stable up to 5 bar (A) then GSSG accumulated to excess. • Complementary investigations of the activity of SOD and CAT validated growth limitations due to oxidative stress.
Collapse
|
13
|
Tsabar M, Mock CS, Venkatachalam V, Reyes J, Karhohs KW, Oliver TG, Regev A, Jambhekar A, Lahav G. A Switch in p53 Dynamics Marks Cells That Escape from DSB-Induced Cell Cycle Arrest. Cell Rep 2020; 32:107995. [PMID: 32755587 PMCID: PMC7521664 DOI: 10.1016/j.celrep.2020.107995] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2019] [Revised: 05/21/2020] [Accepted: 07/14/2020] [Indexed: 01/01/2023] Open
Abstract
Cellular responses to stimuli can evolve over time, resulting in distinct early and late phases in response to a single signal. DNA damage induces a complex response that is largely orchestrated by the transcription factor p53, whose dynamics influence whether a damaged cell will arrest and repair the damage or will initiate cell death. How p53 responses and cellular outcomes evolve in the presence of continuous DNA damage remains unknown. Here, we have found that a subset of cells switches from oscillating to sustained p53 dynamics several days after undergoing damage. The switch results from cell cycle progression in the presence of damaged DNA, which activates the caspase-2-PIDDosome, a complex that stabilizes p53 by inactivating its negative regulator MDM2. This work defines a molecular pathway that is activated if the canonical checkpoints fail to halt mitosis in the presence of damaged DNA.
Collapse
Affiliation(s)
- Michael Tsabar
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA; Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA 02115, USA; Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Caroline S Mock
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Veena Venkatachalam
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA; Harvard Radiation Oncology Program, Harvard Medical School, Boston, MA 02115, USA
| | - Jose Reyes
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Kyle W Karhohs
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Trudy G Oliver
- Huntsman Cancer Institute at University of Utah, Salt Lake City, UT 84112, USA
| | - Aviv Regev
- Broad Institute of MIT and Harvard, Cambridge, MA 02142, USA
| | - Ashwini Jambhekar
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA
| | - Galit Lahav
- Department of Systems Biology, Harvard Medical School, Boston, MA 02115, USA; Laboratory of Systems Pharmacology, Harvard Medical School, Boston, MA 02115, USA.
| |
Collapse
|
14
|
PIBF1 suppresses the ATR/CHK1 signaling pathway and promotes proliferation and motility of triple-negative breast cancer cells. Breast Cancer Res Treat 2020; 182:591-600. [PMID: 32529408 DOI: 10.1007/s10549-020-05732-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2020] [Accepted: 06/05/2020] [Indexed: 02/06/2023]
Abstract
PURPOSE This study evaluates the oncogenic role of PIBF1 in triple-negative breast cancer (TNBC). TNBC is considered to have a poorer prognosis than other types of breast cancer and is associated with high risk of recurrence and distant metastasis. Currently, there are no effective therapies for the TNBC patients with distant metastasis due to the lack of targeted therapeutic options. METHODS The effects of PIBF1 knockdown on the cell viability and motility of TNBC cell lines were investigated. Effects of PIBF1 overexpression on tumorigenicity and cell motility were confirmed using Ba/F3 cell line and xenograft study on BALB/c nude mice. RESULTS In TNBC cell lines that highly express PIBF1, knockdown of PIBF1 induces apoptosis and suppresses cell viability and motility with activation of the ATR/CHK1 signaling pathway. Moreover, the oncogenic function of PIBF1 was confirmed using the Ba/F3 cell line. CONCLUSION For the first time, these findings clarify the role of PIBF1 in regulating ATR/CHK1 signaling pathway and inhibiting the proliferation and migration of TNBC cell lines. These results demonstrate the oncogenic roles of PIBF1 and provide new insights into the function and the molecular mechanism of PIBF1 in malignant TNBC.
Collapse
|
15
|
Morafraile EC, Hänni C, Allen G, Zeisner T, Clarke C, Johnson MC, Santos MM, Carroll L, Minchell NE, Baxter J, Banks P, Lydall D, Zegerman P. Checkpoint inhibition of origin firing prevents DNA topological stress. Genes Dev 2019; 33:1539-1554. [PMID: 31624083 PMCID: PMC6824463 DOI: 10.1101/gad.328682.119] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Accepted: 09/13/2019] [Indexed: 12/22/2022]
Abstract
A universal feature of DNA damage and replication stress in eukaryotes is the activation of a checkpoint-kinase response. In S-phase, the checkpoint inhibits replication initiation, yet the function of this global block to origin firing remains unknown. To establish the physiological roles of this arm of the checkpoint, we analyzed separation of function mutants in the budding yeast Saccharomyces cerevisiae that allow global origin firing upon replication stress, despite an otherwise normal checkpoint response. Using genetic screens, we show that lack of the checkpoint-block to origin firing results in a dependence on pathways required for the resolution of topological problems. Failure to inhibit replication initiation indeed causes increased DNA catenation, resulting in DNA damage and chromosome loss. We further show that such topological stress is not only a consequence of a failed checkpoint response but also occurs in an unperturbed S-phase when too many origins fire simultaneously. Together we reveal that the role of limiting the number of replication initiation events is to prevent DNA topological problems, which may be relevant for the treatment of cancer with both topoisomerase and checkpoint inhibitors.
Collapse
Affiliation(s)
- Esther C Morafraile
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - Christine Hänni
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - George Allen
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - Theresa Zeisner
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - Caroline Clarke
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - Mark C Johnson
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - Miguel M Santos
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - Lauren Carroll
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| | - Nicola E Minchell
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, United Kingdom
| | - Jonathan Baxter
- Genome Damage and Stability Centre, University of Sussex, Falmer, Brighton, East Sussex BN1 9RQ, United Kingdom
| | - Peter Banks
- Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Dave Lydall
- Institute for Cell and Molecular Biosciences, The Medical School, Newcastle University, Newcastle upon Tyne NE2 4HH, United Kingdom
| | - Philip Zegerman
- Wellcome Trust/Cancer Research UK Gurdon Institute and Department of Biochemistry, University of Cambridge CB2 1QN, United Kingdom
| |
Collapse
|
16
|
Krenning L, van den Berg J, Medema RH. Life or Death after a Break: What Determines the Choice? Mol Cell 2019; 76:346-358. [PMID: 31561953 DOI: 10.1016/j.molcel.2019.08.023] [Citation(s) in RCA: 52] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/09/2019] [Revised: 08/19/2019] [Accepted: 08/26/2019] [Indexed: 01/22/2023]
Abstract
DNA double-strand breaks (DSBs) pose a constant threat to genomic integrity. Such DSBs need to be repaired to preserve homeostasis at both the cellular and organismal levels. Hence, the DNA damage response (DDR) has evolved to repair these lesions and limit their toxicity. The initiation of DNA repair depends on the activation of the DDR, and we know that the strength of DDR signaling may differentially affect cellular viability. However, we do not fully understand what determines the cytotoxicity of a DSB. Recent work has identified genomic location, (in)correct DNA repair pathway usage, and cell-cycle position as contributors to DSB-induced cytotoxicity. In this review, we discuss how these determinants affect cytotoxicity, highlight recent discoveries, and identify open questions that could help to improve our understanding about cell fate decisions after a DNA DSB.
Collapse
Affiliation(s)
- Lenno Krenning
- Division of Cell Biology, Oncode Institute, Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - Jeroen van den Berg
- Division of Cell Biology, Oncode Institute, Netherlands Cancer Institute, Amsterdam, the Netherlands
| | - René H Medema
- Division of Cell Biology, Oncode Institute, Netherlands Cancer Institute, Amsterdam, the Netherlands.
| |
Collapse
|
17
|
Arata Y, Takagi H. Quantitative Studies for Cell-Division Cycle Control. Front Physiol 2019; 10:1022. [PMID: 31496950 PMCID: PMC6713215 DOI: 10.3389/fphys.2019.01022] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/24/2019] [Indexed: 11/13/2022] Open
Abstract
The cell-division cycle (CDC) is driven by cyclin-dependent kinases (CDKs). Mathematical models based on molecular networks, as revealed by molecular and genetic studies, have reproduced the oscillatory behavior of CDK activity. Thus, one basic system for representing the CDC is a biochemical oscillator (CDK oscillator). However, genetically clonal cells divide with marked variability in their total duration of a single CDC round, exhibiting non-Gaussian statistical distributions. Therefore, the CDK oscillator model does not account for the statistical nature of cell-cycle control. Herein, we review quantitative studies of the statistical properties of the CDC. Over the past 70 years, studies have shown that the CDC is driven by a cluster of molecular oscillators. The CDK oscillator is coupled to transcriptional and mitochondrial metabolic oscillators, which cause deterministic chaotic dynamics for the CDC. Recent studies in animal embryos have raised the possibility that the dynamics of molecular oscillators underlying CDC control are affected by allometric volume scaling among the cellular compartments. Considering these studies, we discuss the idea that a cluster of molecular oscillators embedded in different cellular compartments coordinates cellular physiology and geometry for successful cell divisions.
Collapse
Affiliation(s)
| | - Hiroaki Takagi
- Department of Physics, School of Medicine, Nara Medical University, Nara, Japan
| |
Collapse
|
18
|
Arroyo M, Kuriyama R, Guerrero I, Keifenheim D, Cañuelo A, Calahorra J, Sánchez A, Clarke DJ, Marchal JA. MCPH1 is essential for cellular adaptation to the G 2-phase decatenation checkpoint. FASEB J 2019; 33:8363-8374. [PMID: 30964711 DOI: 10.1096/fj.201802009rr] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Cellular checkpoints controlling entry into mitosis monitor the integrity of the DNA and delay mitosis onset until the alteration is fully repaired. However, this canonical response can weaken, leading to a spontaneous bypass of the checkpoint, a process referred to as checkpoint adaptation. Here, we have investigated the contribution of microcephalin 1 (MCPH1), mutated in primary microcephaly, to the decatenation checkpoint, a less-understood G2 pathway that delays entry into mitosis until chromosomes are properly disentangled. Our results demonstrate that, although MCPH1 function is dispensable for activation and maintenance of the decatenation checkpoint, it is required for the adaptive response that bypasses the topoisomerase II inhibition----mediated G2 arrest. MCPH1, however, does not confer adaptation to the G2 arrest triggered by the ataxia telangiectasia mutated- and ataxia telangiectasia and rad3 related-based DNA damage checkpoint. In addition to revealing a new role for MCPH1 in cell cycle control, our study provides new insights into the genetic requirements that allow cellular adaptation to G2 checkpoints, a process that remains poorly understood.-Arroyo, M., Kuriyama, R., Guerrero, I., Keifenheim, D., Cañuelo, A., Calahorra, J., Sánchez, A., Clarke, D. J., Marchal, J. A. MCPH1 is essential for cellular adaptation to the G2-phase decatenation checkpoint.
Collapse
Affiliation(s)
- María Arroyo
- Departamento de Biología Experimental, Universidad de Jaén, Jaén, Spain
| | - Ryoko Kuriyama
- Department of Genetics, Cell Biology, and Development, University of Minnesota-Minneapolis, Minneapolis, Minnesota, USA
| | - Israel Guerrero
- Instituto de Investigación y Formación Agraria y Pesquera (IFAPA Centro El Toruño), El Puerto de Santa María, Spain
| | - Daniel Keifenheim
- Department of Genetics, Cell Biology, and Development, University of Minnesota-Minneapolis, Minneapolis, Minnesota, USA
| | - Ana Cañuelo
- Departamento de Biología Experimental, Universidad de Jaén, Jaén, Spain
| | - Jesús Calahorra
- Departamento de Biología Experimental, Universidad de Jaén, Jaén, Spain
| | - Antonio Sánchez
- Departamento de Biología Experimental, Universidad de Jaén, Jaén, Spain
| | - Duncan J Clarke
- Department of Genetics, Cell Biology, and Development, University of Minnesota-Minneapolis, Minneapolis, Minnesota, USA
| | - J Alberto Marchal
- Departamento de Biología Experimental, Universidad de Jaén, Jaén, Spain
| |
Collapse
|
19
|
Lee JY, Lim W, Ryu S, Kim J, Song G. Ochratoxin A mediates cytotoxicity through the MAPK signaling pathway and alters intracellular homeostasis in bovine mammary epithelial cells. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2019; 246:366-373. [PMID: 30577004 DOI: 10.1016/j.envpol.2018.12.032] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Revised: 11/18/2018] [Accepted: 12/11/2018] [Indexed: 06/09/2023]
Abstract
Ochratoxin A (OTA), a secondary metabolite of the genera Penicillium and Aspergillus, contaminates many types of food and causes apoptosis as well as immunosuppression in many animal species. However, a mechanistic analysis of OTA-mediated cytotoxicity in bovine mammary epithelial cells has not yet been performed. Hence, we investigated the effects of OTA on bovine mammary epithelial (MAC-T) cells using several mechanistic analyses. We report that OTA may induce cell cycle arrest and apoptosis via MAPK and JNK signaling pathways in MAC-T cells. Moreover, homeostasis of cellular components, such as that of the mitochondrial membrane, was disrupted by OTA, leading to a decrease in mitochondrial and cytosolic Ca2+ in MAC-T cells. In addition, we evaluated the effects of OTA on inflammatory responses and major tight junction regulators, such as occludin and claudin 3. In summation, we suggest that OTA contamination may adversely affect bovine mammary epithelial cells, leading to improper lactation and decreased milk quality. This article aims to improve the understanding of physiological mechanisms involved in lactation, in addition to providing a guideline for the stabilization of industrial milk production by countering exogenous contaminants in livestock.
Collapse
Affiliation(s)
- Jin-Young Lee
- Department of Pharmacy, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Whasun Lim
- Department of Biomedical Sciences, Catholic Kwandong University, Gangneung, 25601, Republic of Korea
| | - Soomin Ryu
- Institute of Animal Molecular Biotechnology and Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea
| | - Jinyoung Kim
- Department of Animal Resources Science, Dankook University, Cheonan, 330-714, Republic of Korea
| | - Gwonhwa Song
- Institute of Animal Molecular Biotechnology and Department of Biotechnology, College of Life Sciences and Biotechnology, Korea University, Seoul, 02841, Republic of Korea.
| |
Collapse
|
20
|
Verma N, Franchitto M, Zonfrilli A, Cialfi S, Palermo R, Talora C. DNA Damage Stress: Cui Prodest? Int J Mol Sci 2019; 20:E1073. [PMID: 30832234 PMCID: PMC6429504 DOI: 10.3390/ijms20051073] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2019] [Revised: 02/18/2019] [Accepted: 02/26/2019] [Indexed: 12/25/2022] Open
Abstract
DNA is an entity shielded by mechanisms that maintain genomic stability and are essential for living cells; however, DNA is constantly subject to assaults from the environment throughout the cellular life span, making the genome susceptible to mutation and irreparable damage. Cells are prepared to mend such events through cell death as an extrema ratio to solve those threats from a multicellular perspective. However, in cells under various stress conditions, checkpoint mechanisms are activated to allow cells to have enough time to repair the damaged DNA. In yeast, entry into the cell cycle when damage is not completely repaired represents an adaptive mechanism to cope with stressful conditions. In multicellular organisms, entry into cell cycle with damaged DNA is strictly forbidden. However, in cancer development, individual cells undergo checkpoint adaptation, in which most cells die, but some survive acquiring advantageous mutations and selfishly evolve a conflictual behavior. In this review, we focus on how, in cancer development, cells rely on checkpoint adaptation to escape DNA stress and ultimately to cell death.
Collapse
Affiliation(s)
- Nagendra Verma
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy.
| | - Matteo Franchitto
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy.
| | - Azzurra Zonfrilli
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy.
| | - Samantha Cialfi
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy.
| | - Rocco Palermo
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy.
| | - Claudio Talora
- Department of Molecular Medicine, Sapienza University of Rome, 00161 Rome, Italy.
| |
Collapse
|
21
|
Bacal J, Moriel-Carretero M, Pardo B, Barthe A, Sharma S, Chabes A, Lengronne A, Pasero P. Mrc1 and Rad9 cooperate to regulate initiation and elongation of DNA replication in response to DNA damage. EMBO J 2018; 37:e99319. [PMID: 30158111 PMCID: PMC6213276 DOI: 10.15252/embj.201899319] [Citation(s) in RCA: 42] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2018] [Revised: 07/17/2018] [Accepted: 07/31/2018] [Indexed: 01/04/2023] Open
Abstract
The S-phase checkpoint maintains the integrity of the genome in response to DNA replication stress. In budding yeast, this pathway is initiated by Mec1 and is amplified through the activation of Rad53 by two checkpoint mediators: Mrc1 promotes Rad53 activation at stalled forks, and Rad9 is a general mediator of the DNA damage response. Here, we have investigated the interplay between Mrc1 and Rad9 in response to DNA damage and found that they control DNA replication through two distinct but complementary mechanisms. Mrc1 rapidly activates Rad53 at stalled forks and represses late-firing origins but is unable to maintain this repression over time. Rad9 takes over Mrc1 to maintain a continuous checkpoint signaling. Importantly, the Rad9-mediated activation of Rad53 slows down fork progression, supporting the view that the S-phase checkpoint controls both the initiation and the elongation of DNA replication in response to DNA damage. Together, these data indicate that Mrc1 and Rad9 play distinct functions that are important to ensure an optimal completion of S phase under replication stress conditions.
Collapse
Affiliation(s)
- Julien Bacal
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - María Moriel-Carretero
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Benjamin Pardo
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Antoine Barthe
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Sushma Sharma
- Department of Medical Biochemistry and Biophysics and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Andrei Chabes
- Department of Medical Biochemistry and Biophysics and Laboratory for Molecular Infection Medicine Sweden (MIMS), Umeå University, Umeå, Sweden
| | - Armelle Lengronne
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| | - Philippe Pasero
- Institut de Génétique Humaine, CNRS, Equipe Labellisée Ligue contre le Cancer, Université de Montpellier, Montpellier, France
| |
Collapse
|
22
|
Qiu L, Zhao C, Wang P, Fan S, Yan L, Xie B, Jiang S, Wang S, Lin H. Genomic structure, expression, and functional characterization of checkpoint kinase 1 from Penaeus monodon. PLoS One 2018; 13:e0198036. [PMID: 29795680 PMCID: PMC5967826 DOI: 10.1371/journal.pone.0198036] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 05/11/2018] [Indexed: 12/14/2022] Open
Abstract
Chk1 is a cell-cycle regulator. Chk1 has been identified in organisms ranging from yeast to humans, but few researchers have studied Chk1 in shrimps. We cloned Chk1 from the black tiger shrimp (Penaeus monodon). The full-length cDNA sequence of PmChk1 had 3,334 base pairs (bp), with an open reading frame of 1,455 bp. The complete genomic sequence of PmChk1 (11,081 bp) contained 10 exons separated by nine introns. qRT-PCR showed that PmChk1 was highly expressed in the ovaries and gills of P. monodon. The lowest PmChk1 expression was noted in stage III of ovarian development in P. monodon. PmChk1 expression decreased significantly after injection of 5-hydroxytryptamine and eyestalk ablation in P. monodon ovaries. RNA interference experiments were undertaken to examine the expression of PmChk1, PmCDC2, and PmCyclin B. PmChk1 knockdown in the ovaries and hepatopancreas by dsRNA-Chk1 was successful. The localization and level of PmChk1 expression in the hepatopancreas was studied using in situ hybridization, which showed that data were in accordance with those of qRT-PCR. The Gonadosomatic Index of P. monodon after dsRNA-Chk1 injection was significantly higher than that after injection of dsRNA-GFP or phosphate-buffered saline. These data suggest that PmChk1 may have important roles in the ovarian maturation of P. monodon.
Collapse
Affiliation(s)
- Lihua Qiu
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou, China
- Key Laboratory of Aquatic Genomics, Ministry of Agriculture, Beijing, China
| | - Chao Zhao
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou, China
| | - Pengfei Wang
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou, China
| | - Sigang Fan
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou, China
| | - Lulu Yan
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou, China
| | - Bobo Xie
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou, China
| | - Shigui Jiang
- South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Key Laboratory of South China Sea Fishery Resources Exploitation and Utilization, Ministry of Agriculture, Guangzhou, China
- South China Sea Resource Exploitation and Protection Collaborative Innovation Center, Sun Yat-Sen University, Guangzhou, China
- * E-mail:
| | - Shu Wang
- Chinese Academy of Fishery Sciences, Beijing, China
| | - Heizhao Lin
- Shenzhen Base of South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Shenzhen, PR China
| |
Collapse
|
23
|
Liu CW, Lin YC, Hung CM, Liu BL, Kuo SC, Ho CT, Way TD, Hung CH. CHM-1, a novel microtubule-destabilizing agent exhibits antitumor activity via inducing the expression of SIRT2 in human breast cancer cells. Chem Biol Interact 2018; 289:98-108. [PMID: 29679549 DOI: 10.1016/j.cbi.2018.04.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2017] [Revised: 03/05/2018] [Accepted: 04/05/2018] [Indexed: 11/28/2022]
Abstract
Breast cancer is a major public health problem throughout the world. In this report, we investigated whether CHM-1, a novel synthetic antimitotic agent could be developed into a potent antitumor agent for treating human breast cancer. CHM-1 induced growth inhibition in MDA-MB-231, MDA-MB-453 and MCF-7 cells in a concentration-dependent manner. Importantly, CHM-1 is less toxic to normal breast (HBL-100) cells. CHM-1 interacted with tubulin, markedly inhibited tubulin polymerization, and disrupted microtubule organization. Proteins from control and CHM-1-treated animal tumor specimens were analyzed by two-dimensional electrophoresis and MALDI-TOF mass spectrometry. Our results indicated that CHM-1 increased the expression of SIRT2 protein, an NAD-dependent tubulin deacetylase. A prodrug strategy was also investigated to address the problem of low aqueous solubility and low bioavailability of the antitumor agent CHM-1. The water-soluble prodrug of CHM-1 (CHM-1-P) was synthesized. After oral and intravenous administration, CHM-1-P induced a dose-dependent inhibition of tumor growth. The aforementioned excellent anti-tumor activity profiles of CHM-1 and its prodrug CHM-1-P, suggests that CHM-1-P deserves to further develop as a clinical trial candidate for treating human breast carcinoma.
Collapse
Affiliation(s)
- Chin-Wei Liu
- Department of Chemical Engineering and Institute of Biotechnology and Chemical Engineering, I-Shou University, Kaohsiung, Taiwan
| | - Ying-Chao Lin
- Division of Neurosurgery, Buddhist Tzu Chi General Hospital, Taichung Branch, Taiwan; School of Medicine, Tzu Chi University, Hualien, Taiwan; Department of Medical Imaging and Radiological Science, Central Taiwan University of Science and Technology, Taichung, Taiwan
| | - Chao-Ming Hung
- Department of General Surgery, E-Da Hospital, I-Shou University, Kaohsiung, Taiwan; School of Medicine, I-Shou University, Kaohsiung, Taiwan
| | - Bing-Lan Liu
- Department of Applied Chemistry, Chaoyang University of Technology, Taichung, Taiwan
| | - Sheng-Chu Kuo
- School of Pharmacy, College of Pharmacy, China Medical University, Taichung, Taiwan
| | - Chi-Tang Ho
- Department of Food Science, Rutgers University, New Brunswick, NJ, USA
| | - Tzong-Der Way
- Department of Biological Science and Technology, College of Biopharmaceutical and Food Sciences, China Medical University, Taichung, Taiwan; Department of Health and Nutrition Biotechnology, Asia University, Taichung, Taiwan.
| | - Chih-Hsin Hung
- Department of Chemical Engineering and Institute of Biotechnology and Chemical Engineering, I-Shou University, Kaohsiung, Taiwan.
| |
Collapse
|
24
|
Moreno-Villanueva M, von Scheven G, Feiveson A, Bürkle A, Wu H, Goel N. The degree of radiation-induced DNA strand breaks is altered by acute sleep deprivation and psychological stress and is associated with cognitive performance in humans. Sleep 2018; 41:4954606. [DOI: 10.1093/sleep/zsy067] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2017] [Indexed: 11/14/2022] Open
Affiliation(s)
- Maria Moreno-Villanueva
- National Aeronautics and Space Administration, Johnson Space Center, Houston, TX
- Department of Biology, Molecular Toxicology Group, University of Konstanz, Konstanz, Germany
| | - Gudrun von Scheven
- Department of Biology, Molecular Toxicology Group, University of Konstanz, Konstanz, Germany
| | - Alan Feiveson
- National Aeronautics and Space Administration, Johnson Space Center, Houston, TX
| | - Alexander Bürkle
- Department of Biology, Molecular Toxicology Group, University of Konstanz, Konstanz, Germany
| | - Honglu Wu
- National Aeronautics and Space Administration, Johnson Space Center, Houston, TX
| | - Namni Goel
- Department of Psychiatry, Division of Sleep and Chronobiology, University of Pennsylvania, Perelman School of Medicine, Philadelphia, PA
| |
Collapse
|
25
|
Arabidopsis TSO1 and MYB3R1 form a regulatory module to coordinate cell proliferation with differentiation in shoot and root. Proc Natl Acad Sci U S A 2018. [PMID: 29535223 DOI: 10.1073/pnas.1715903115] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Fundamental to plant and animal development is the regulated balance between cell proliferation and differentiation, a process intimately tied to cell cycle regulation. In Arabidopsis, mutations in TSO1, whose animal homolog is LIN54, resulted in severe developmental abnormalities both in shoot and root, including shoot meristem fasciation and reduced root meristematic zone. The molecular mechanism that could explain the tso1 mutant phenotype is absent. Through a genetic screen, we identified 32 suppressors that map to the MYB3R1 gene, encoding a conserved cell cycle regulator. Further analysis indicates that TSO1 transcriptionally represses MYB3R1, and the ectopic MYB3R1 activity mediates the tso1 mutant phenotype. Since animal homologs of TSO1 and MYB3R1 are components of a cell cycle regulatory complex, the DREAM complex, we tested and showed that TSO1 and MYB3R1 coimmunoprecipitated in tobacco leaf cells. Our work reveals a conserved cell cycle regulatory module, consisting of TSO1 and MYB3R1, for proper plant development.
Collapse
|
26
|
Dalmau N, Andrieu-Abadie N, Tauler R, Bedia C. Untargeted lipidomic analysis of primary human epidermal melanocytes acutely and chronically exposed to UV radiation. Mol Omics 2018; 14:170-180. [DOI: 10.1039/c8mo00060c] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Ultraviolet (UV) radiation present in sunlight has been related to harmful effects on skin such as premature aging and skin cancer.
Collapse
Affiliation(s)
- Núria Dalmau
- Department of Environmental Chemistry
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC)
- 08034 Barcelona
- Spain
| | | | - Romà Tauler
- Department of Environmental Chemistry
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC)
- 08034 Barcelona
- Spain
| | - Carmen Bedia
- Department of Environmental Chemistry
- Institute of Environmental Assessment and Water Research (IDAEA-CSIC)
- 08034 Barcelona
- Spain
| |
Collapse
|
27
|
Chao HX, Poovey CE, Privette AA, Grant GD, Chao HY, Cook JG, Purvis JE. Orchestration of DNA Damage Checkpoint Dynamics across the Human Cell Cycle. Cell Syst 2017; 5:445-459.e5. [PMID: 29102360 PMCID: PMC5700845 DOI: 10.1016/j.cels.2017.09.015] [Citation(s) in RCA: 112] [Impact Index Per Article: 16.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2017] [Revised: 06/26/2017] [Accepted: 09/22/2017] [Indexed: 10/18/2022]
Abstract
Although molecular mechanisms that prompt cell-cycle arrest in response to DNA damage have been elucidated, the systems-level properties of DNA damage checkpoints are not understood. Here, using time-lapse microscopy and simulations that model the cell cycle as a series of Poisson processes, we characterize DNA damage checkpoints in individual, asynchronously proliferating cells. We demonstrate that, within early G1 and G2, checkpoints are stringent: DNA damage triggers an abrupt, all-or-none cell-cycle arrest. The duration of this arrest correlates with the severity of DNA damage. After the cell passes commitment points within G1 and G2, checkpoint stringency is relaxed. By contrast, all of S phase is comparatively insensitive to DNA damage. This checkpoint is graded: instead of halting the cell cycle, increasing DNA damage leads to slower S phase progression. In sum, we show that a cell's response to DNA damage depends on its exact cell-cycle position and that checkpoints are phase-dependent, stringent or relaxed, and graded or all-or-none.
Collapse
Affiliation(s)
- Hui Xiao Chao
- Department of Genetics, University of North Carolina, Chapel Hill, Genetic Medicine Building 5061, CB#7264, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA; Curriculum for Bioinformatics and Computational Biology, University of North Carolina, Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA
| | - Cere E Poovey
- Department of Genetics, University of North Carolina, Chapel Hill, Genetic Medicine Building 5061, CB#7264, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA
| | - Ashley A Privette
- Department of Genetics, University of North Carolina, Chapel Hill, Genetic Medicine Building 5061, CB#7264, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA
| | - Gavin D Grant
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA
| | - Hui Yan Chao
- Department of Genetics, University of North Carolina, Chapel Hill, Genetic Medicine Building 5061, CB#7264, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA
| | - Jeanette G Cook
- Department of Biochemistry and Biophysics, University of North Carolina, Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA
| | - Jeremy E Purvis
- Department of Genetics, University of North Carolina, Chapel Hill, Genetic Medicine Building 5061, CB#7264, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA; Curriculum for Bioinformatics and Computational Biology, University of North Carolina, Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA; Lineberger Comprehensive Cancer Center, University of North Carolina, Chapel Hill, 120 Mason Farm Road, Chapel Hill, NC 27599-7264, USA.
| |
Collapse
|
28
|
Pathways and Mechanisms that Prevent Genome Instability in Saccharomyces cerevisiae. Genetics 2017; 206:1187-1225. [PMID: 28684602 PMCID: PMC5500125 DOI: 10.1534/genetics.112.145805] [Citation(s) in RCA: 37] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/17/2016] [Accepted: 04/26/2017] [Indexed: 12/13/2022] Open
Abstract
Genome rearrangements result in mutations that underlie many human diseases, and ongoing genome instability likely contributes to the development of many cancers. The tools for studying genome instability in mammalian cells are limited, whereas model organisms such as Saccharomyces cerevisiae are more amenable to these studies. Here, we discuss the many genetic assays developed to measure the rate of occurrence of Gross Chromosomal Rearrangements (called GCRs) in S. cerevisiae. These genetic assays have been used to identify many types of GCRs, including translocations, interstitial deletions, and broken chromosomes healed by de novo telomere addition, and have identified genes that act in the suppression and formation of GCRs. Insights from these studies have contributed to the understanding of pathways and mechanisms that suppress genome instability and how these pathways cooperate with each other. Integrated models for the formation and suppression of GCRs are discussed.
Collapse
|
29
|
G2/M checkpoint plays a vital role at the early stage of HCC by analysis of key pathways and genes. Oncotarget 2017; 8:76305-76317. [PMID: 29100313 PMCID: PMC5652707 DOI: 10.18632/oncotarget.19351] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 06/29/2017] [Indexed: 01/14/2023] Open
Abstract
The present study was designed to explore the molecular mechanism at the early stage of hepatocarcinoma (HCC) and identify the candidate genes and pathways changed significantly. We downloaded the gene expression file dataset GSE6764 from GEO, adopted the Robust Multi-array Average (RMA) algorithm to preprocess the raw file. 797 differentially expressed genes (DEGs) were screened out based on the SAM method using R language. Ingenuity Pathway Analysis (IPA) was used to perform canonical pathway analysis in order to calculate the most significantly changed pathways and predict the upstream regulators. In order to confirm the results from the DEGs which based on the individual gene level, the gene set enrichment analysis (GSEA) was done from the gene set level and the leading edge analysis was performed to find out the most appeared genes in several gene sets. The PPI network was built using GeneMANIA and the key genes were calculated using cytoHubba plugin based on cytoscape 3.4.0. We found that the Cell Cycle: G2/M DNA damage checkpoint regulation is the top-ranked pathways at the early stage of HCC by IPA. The high expression of several genes including CCNB1, CDC25B, XPO1, GMPS, KPNA2 and MELK is correlated with high risk, poor prognosis and shorter overall survival time in HCC patients by use of Kaplan-Meier Survival analysis. Taken together, our study showed that the G2/M checkpoint plays a vital role at the early HCC and the genes participate in the process may serve as biomarkers for the diagnosis and prognosis.
Collapse
|
30
|
Shrinking Daughters: Rlm1-Dependent G 1/S Checkpoint Maintains Saccharomyces cerevisiae Daughter Cell Size and Viability. Genetics 2017. [PMID: 28637712 DOI: 10.1534/genetics.117.204206] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023] Open
Abstract
The Rlm1 transcription factor is a target of the cell wall integrity pathway. We report that an rlm1Δ mutant grown on a nonfermentable carbon source at low osmolarity forms cell groups in which a mother cell is surrounded by smaller "satellite-daughter" cells. Mother cells in these groups progressed through repeated rounds of cell division with normal rates of bud growth and genetic stability; however, these cells underwent precocious START relative to wild-type mothers. Thus, once activated, Rlm1 delays the transition from G1 to S, a mechanism we term the cell wall/START (CW/START) checkpoint. The rlm1Δ satellite-cell phenotype is suppressed by deletion of either SLT2, which encodes the kinase that activates Rlm1, or SWI4, which is also activated by Slt2; suggesting that Slt2 can have opposing roles in regulating the START transition. Consistent with an Rlm1-dependent CW/START checkpoint, rlm1Δ satellite daughters were unable to grow or divide further even after transfer to rich medium, but UV irradiation in G1 could partially rescue rlm1Δ satellite daughters in the next division. Indeed, after cytokinesis, these satellite daughters shrank rapidly, displayed amorphous actin staining, and became more permeable. As a working hypothesis, we propose that duplication of an "actin-organizing center" in late G1 may be required both to progress through START and to reestablish the actin cytoskeleton in daughter cells.
Collapse
|
31
|
Perez AM, Finnigan GC, Roelants FM, Thorner J. Septin-Associated Protein Kinases in the Yeast Saccharomyces cerevisiae. Front Cell Dev Biol 2016; 4:119. [PMID: 27847804 PMCID: PMC5088441 DOI: 10.3389/fcell.2016.00119] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2016] [Accepted: 10/14/2016] [Indexed: 01/19/2023] Open
Abstract
Septins are a family of eukaryotic GTP-binding proteins that associate into linear rods, which, in turn, polymerize end-on-end into filaments, and further assemble into other, more elaborate super-structures at discrete subcellular locations. Hence, septin-based ensembles are considered elements of the cytoskeleton. One function of these structures that has been well-documented in studies conducted in budding yeast Saccharomyces cerevisiae is to serve as a scaffold that recruits regulatory proteins, which dictate the spatial and temporal control of certain aspects of the cell division cycle. In particular, septin-associated protein kinases couple cell cycle progression with cellular morphogenesis. Thus, septin-containing structures serve as signaling platforms that integrate a multitude of signals and coordinate key downstream networks required for cell cycle passage. This review summarizes what we currently understand about how the action of septin-associated protein kinases and their substrates control information flow to drive the cell cycle into and out of mitosis, to regulate bud growth, and especially to direct timely and efficient execution of cytokinesis and cell abscission. Thus, septin structures represent a regulatory node at the intersection of many signaling pathways. In addition, and importantly, the activities of certain septin-associated protein kinases also regulate the state of organization of the septins themselves, creating a complex feedback loop.
Collapse
Affiliation(s)
- Adam M Perez
- Division of Biochemistry, Biophysics and Structural Biology, Department of Molecular and Cell Biology, University of California, Berkeley Berkeley, CA, USA
| | - Gregory C Finnigan
- Division of Biochemistry, Biophysics and Structural Biology, Department of Molecular and Cell Biology, University of California, Berkeley Berkeley, CA, USA
| | - Françoise M Roelants
- Division of Biochemistry, Biophysics and Structural Biology, Department of Molecular and Cell Biology, University of California, Berkeley Berkeley, CA, USA
| | - Jeremy Thorner
- Division of Biochemistry, Biophysics and Structural Biology, Department of Molecular and Cell Biology, University of California, Berkeley Berkeley, CA, USA
| |
Collapse
|
32
|
Cherukupalli S, Karpoormath R, Chandrasekaran B, Hampannavar GA, Thapliyal N, Palakollu VN. An insight on synthetic and medicinal aspects of pyrazolo[1,5-a]pyrimidine scaffold. Eur J Med Chem 2016; 126:298-352. [PMID: 27894044 DOI: 10.1016/j.ejmech.2016.11.019] [Citation(s) in RCA: 97] [Impact Index Per Article: 12.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 10/19/2016] [Accepted: 11/08/2016] [Indexed: 11/26/2022]
Abstract
Pyrazolo[1,5-a]pyrimidine scaffold is one of the privileged hetrocycles in drug discovery. Its application as a buliding block for developing drug-like candidates has displayed broad range of medicinal properties such as anticancer, CNS agents, anti-infectious, anti-inflammatory, CRF1 antagonists and radio diagnostics. The structure-activity relationship (SAR) studies have acquired greater attention amid medicinal chemists, and many of the lead compounds were derived for various disease targets. However, there is plenty of room for the medicinal chemists to further exploit this privileged scaffold in developing potential drug candidates. The present review briefly outlines relevant synthetic strategies employed for pyrazolo[1,5-a]pyrimidine derivatives. It also extensively reveals significant biological properties along with SAR studies. To the best of our understanding current review is the first attempt made towards the compilation of significant advances made on pyrazolo[1,5-a]pyrimidines reported since 1980s.
Collapse
Affiliation(s)
- Srinivasulu Cherukupalli
- Department of Pharmaceutical Chemistry, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
| | - Rajshekhar Karpoormath
- Department of Pharmaceutical Chemistry, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa.
| | - Balakumar Chandrasekaran
- Department of Pharmaceutical Chemistry, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
| | - Girish A Hampannavar
- Department of Pharmaceutical Chemistry, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
| | - Neeta Thapliyal
- Department of Pharmaceutical Chemistry, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
| | - Venkata Narayana Palakollu
- Department of Pharmaceutical Chemistry, College of Health Sciences, University of KwaZulu-Natal, Durban 4000, South Africa
| |
Collapse
|
33
|
Pare R, Shin JS, Lee CS. Increased expression of senescence markers p14(ARF) and p16(INK4a) in breast cancer is associated with an increased risk of disease recurrence and poor survival outcome. Histopathology 2016; 69:479-91. [PMID: 26843058 DOI: 10.1111/his.12948] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2015] [Accepted: 01/31/2016] [Indexed: 11/28/2022]
Abstract
AIMS Breast cancer is a hormonally driven disease. Cellular senescence is an age-related irreversible cell cycle arrest at the G1 phase upon induction. The aim of this study was to characterize the expression patterns of the senescence markers p14(ARF) , p16(INK4a) and p21(WAF1/Cip1) during breast cancer progression in a large patient cohort. METHODS AND RESULTS We conducted a retrospective study of 1080 patients with invasive ductal carcinoma, no special type, over an 11-year period. We performed immunohistochemical staining on tissue microarrays that included normal, benign hyperplasia, ductal carcinoma in situ and invasive ductal carcinoma tissue from each patient. Invasive ductal carcinomas showed higher expression of p14(ARF) and p16(INK4a) but lower expression of p21(WAF1/Cip1) than non-malignant tissues. There were significant correlations of normal, benign, preinvasive and malignant tissues with p14(ARF) , p16(INK4a) and p21(WAF1/Cip1) expression (P < 0.05). Univariate comparison showed a correlation between high p16(INK4a) expression and poor survival (P = 0.000) and an increased risk of relapse (P = 0.000), whereas high p14(ARF) expression correlated only with an increased risk of relapse (P = 0.038). Multivariate analysis showed p16(INK4a) to be an important prognostic factor for overall survival (P = 0.011) and disease-free survival (P = 0.004), with p14(ARF) also being a significant prognostic factor for disease-free survival (P = 0.043). Moreover, patients showing both high p16(INK4a) expression and and high p14(ARF) expression had an adjusted three-fold increased risk of disease recurrence (P < 0.05) and a two-fold increased risk of all-cause-related death (P < 0.05). CONCLUSIONS These finding suggest p16(INK4a) expression and p14(ARF) expression may play an important role in the progression of proliferative breast tissue to invasive cancer, and may be useful as prognostic factors.
Collapse
Affiliation(s)
- Rahmawati Pare
- Discipline of Pathology, School of Medicine, Western Sydney University, Liverpool, NSW, Australia.,Ingham Institute for Applied Medical Research, Liverpool, NSW, Australia
| | - Joo-Shik Shin
- Discipline of Pathology, School of Medicine, Western Sydney University, Liverpool, NSW, Australia.,Ingham Institute for Applied Medical Research, Liverpool, NSW, Australia.,Department of Anatomical Pathology, Liverpool Hospital, Liverpool, NSW, Australia
| | - Cheok Soon Lee
- Discipline of Pathology, School of Medicine, Western Sydney University, Liverpool, NSW, Australia.,Ingham Institute for Applied Medical Research, Liverpool, NSW, Australia.,Department of Anatomical Pathology, Liverpool Hospital, Liverpool, NSW, Australia.,Cancer Pathology, Bosch Institute, University of Sydney, Sydney, NSW, Australia.,South Western Sydney Clinical School, University of New South Wales, Sydney, NSW, Australia
| |
Collapse
|
34
|
Rovigatti U. Cancer modelling in the NGS era - Part I: Emerging technology and initial modelling. Crit Rev Oncol Hematol 2015; 96:274-307. [PMID: 26427785 DOI: 10.1016/j.critrevonc.2015.05.017] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2014] [Revised: 04/14/2015] [Accepted: 05/19/2015] [Indexed: 02/07/2023] Open
Abstract
It is today indisputable that great progresses have been made in our molecular understanding of cancer cells, but an effective implementation of such knowledge into dramatic cancer-cures is still belated and yet desperately needed. This review gives a snapshot at where we stand today in this search for cancer understanding and definitive treatments, how far we have progressed and what are the major obstacles we will have to overcome both technologically and for disease modelling. In the first part, promising 3rd/4th Generation Sequencing Technologies will be summarized (particularly IonTorrent and OxfordNanopore technologies). Cancer modelling will be then reviewed from its origin in XIX Century Germany to today's NGS applications for cancer understanding and therapeutic interventions. Developments after Molecular Biology revolution (1953) are discussed as successions of three phases. The first, PH1, labelled "Clonal Outgrowth" (from 1960s to mid 1980s) was characterized by discoveries in cytogenetics (Nowell, Rowley) and viral oncology (Dulbecco, Bishop, Varmus), which demonstrated clonality. Treatments were consequently dominated by a "cytotoxic eradication" strategy with chemotherapeutic agents. In PH2, (from the mid 1980s to our days) the description of cancer as "Gene Networks" led to targeted-gene-therapies (TGTs). TGTs are the focus of Section 3: in view of their apparent failing (Ephemeral Therapies), alternative strategies will be discussed in review part II (particularly cancer immunotherapy, CIT). Additional Pitfalls impinge on the concepts of tumour heterogeneity (inter/intra; ITH). The described pitfalls set the basis for a new phase, PH3, which is called "NGS Era" and will be also discussed with ten emerging cancer models in the Review 2nd part.
Collapse
Affiliation(s)
- Ugo Rovigatti
- University of Pisa Medical School, Oncology Department, via Roma 55, 56127 Pisa, Italy.
| |
Collapse
|
35
|
Shaltiel IA, Krenning L, Bruinsma W, Medema RH. The same, only different - DNA damage checkpoints and their reversal throughout the cell cycle. J Cell Sci 2015; 128:607-20. [PMID: 25609713 DOI: 10.1242/jcs.163766] [Citation(s) in RCA: 184] [Impact Index Per Article: 20.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022] Open
Abstract
Cell cycle checkpoints activated by DNA double-strand breaks (DSBs) are essential for the maintenance of the genomic integrity of proliferating cells. Following DNA damage, cells must detect the break and either transiently block cell cycle progression, to allow time for repair, or exit the cell cycle. Reversal of a DNA-damage-induced checkpoint not only requires the repair of these lesions, but a cell must also prevent permanent exit from the cell cycle and actively terminate checkpoint signalling to allow cell cycle progression to resume. It is becoming increasingly clear that despite the shared mechanisms of DNA damage detection throughout the cell cycle, the checkpoint and its reversal are precisely tuned to each cell cycle phase. Furthermore, recent findings challenge the dogmatic view that complete repair is a precondition for cell cycle resumption. In this Commentary, we highlight cell-cycle-dependent differences in checkpoint signalling and recovery after a DNA DSB, and summarise the molecular mechanisms that underlie the reversal of DNA damage checkpoints, before discussing when and how cell fate decisions after a DSB are made.
Collapse
Affiliation(s)
- Indra A Shaltiel
- The Netherlands Cancer Institute, Division of Cell Biology, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Lenno Krenning
- The Netherlands Cancer Institute, Division of Cell Biology, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - Wytse Bruinsma
- The Netherlands Cancer Institute, Division of Cell Biology, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| | - René H Medema
- The Netherlands Cancer Institute, Division of Cell Biology, Plesmanlaan 121, 1066 CX Amsterdam, The Netherlands
| |
Collapse
|
36
|
Abstract
Bacteria can rapidly evolve resistance to antibiotics via the SOS response, a state of high-activity DNA repair and mutagenesis. We explore here the first steps of this evolution in the bacterium Escherichia coli. Induction of the SOS response by the genotoxic antibiotic ciprofloxacin changes the E. coli rod shape into multichromosome-containing filaments. We show that at subminimal inhibitory concentrations of ciprofloxacin the bacterial filament divides asymmetrically repeatedly at the tip. Chromosome-containing buds are made that, if resistant, propagate nonfilamenting progeny with enhanced resistance to ciprofloxacin as the parent filament dies. We propose that the multinucleated filament creates an environmental niche where evolution can proceed via generation of improved mutant chromosomes due to the mutagenic SOS response and possible recombination of the new alleles between chromosomes. Our data provide a better understanding of the processes underlying the origin of resistance at the single-cell level and suggest an analogous role to the eukaryotic aneuploidy condition in cancer.
Collapse
|
37
|
Huang S. Genetic and non-genetic instability in tumor progression: link between the fitness landscape and the epigenetic landscape of cancer cells. Cancer Metastasis Rev 2014; 32:423-48. [PMID: 23640024 DOI: 10.1007/s10555-013-9435-7] [Citation(s) in RCA: 99] [Impact Index Per Article: 9.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/25/2022]
Abstract
Genetic instability is invoked in explaining the cell phenotype changes that take place during cancer progression. However, the coexistence of a vast diversity of distinct clones, most prominently visible in the form of non-clonal chromosomal aberrations, suggests that Darwinian selection of mutant cells is not operating at maximal efficacy. Conversely, non-genetic instability of cancer cells must also be considered. Such mutation-independent instability of cell states is most prosaically manifest in the phenotypic heterogeneity within clonal cell populations or in the reversible switching between immature "cancer stem cell-like" and more differentiated states. How are genetic and non-genetic instability related to each other? Here, we review basic theoretical foundations and offer a dynamical systems perspective in which cancer is the inevitable pathological manifestation of modes of malfunction that are immanent to the complex gene regulatory network of the genome. We explain in an accessible, qualitative, and permissively simplified manner the mathematical basis for the "epigenetic landscape" and how the latter relates to the better known "fitness landscape." We show that these two classical metaphors have a formal basis. By combining these two landscape concepts, we unite development and somatic evolution as the drivers of the relentless increase in malignancy. Herein, the cancer cells are pushed toward cancer attractors in the evolutionarily unused regions of the epigenetic landscape that encode more and more "dedifferentiated" states as a consequence of both genetic (mutagenic) and non-genetic (regulatory) perturbations-including therapy. This would explain why for the cancer cell, the principle of "What does not kill me makes me stronger" is as much a driving force in tumor progression and development of drug resistance as the simple principle of "survival of the fittest."
Collapse
Affiliation(s)
- Sui Huang
- Institute for Systems Biology, Seattle, WA, USA,
| |
Collapse
|
38
|
Kawasumi M, Bradner JE, Tolliday N, Thibodeau R, Sloan H, Brummond KM, Nghiem P. Identification of ATR-Chk1 pathway inhibitors that selectively target p53-deficient cells without directly suppressing ATR catalytic activity. Cancer Res 2014; 74:7534-45. [PMID: 25336189 DOI: 10.1158/0008-5472.can-14-2650] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Resistance to DNA-damaging chemotherapy is a barrier to effective treatment that appears to be augmented by p53 functional deficiency in many cancers. In p53-deficient cells in which the G1-S checkpoint is compromised, cell viability after DNA damage relies upon intact intra-S and G2-M checkpoints mediated by the ATR (ataxia telangiectasia and Rad3 related) and Chk1 kinases. Thus, a logical rationale to sensitize p53-deficient cancers to DNA-damaging chemotherapy is through the use of ATP-competitive inhibitors of ATR or Chk1. To discover small molecules that may act on uncharacterized components of the ATR pathway, we performed a phenotype-based screen of 9,195 compounds for their ability to inhibit hydroxyurea-induced phosphorylation of Ser345 on Chk1, known to be a critical ATR substrate. This effort led to the identification of four small-molecule compounds, three of which were derived from known bioactive library (anthothecol, dihydrocelastryl, and erysolin) and one of which was a novel synthetic compound termed MARPIN. These compounds all inhibited ATR-selective phosphorylation and sensitized p53-deficient cancer cells to DNA-damaging agents in vitro and in vivo. Notably, these compounds did not inhibit ATR catalytic activity in vitro, unlike typical ATP-competitive inhibitors, but acted in a mechanistically distinct manner to disable ATR-Chk1 function. Our results highlight a set of novel molecular probes to further elucidate druggable mechanisms to improve cancer therapeutic responses produced by DNA-damaging drugs.
Collapse
Affiliation(s)
- Masaoki Kawasumi
- Division of Dermatology, Department of Medicine, University of Washington, Seattle, Washington.
| | - James E Bradner
- The Broad Institute of MIT and Harvard, Cambridge, Massachusetts. Department of Medical Oncology, Dana-Farber Cancer Institute, Boston, Massachusetts. Department of Medicine, Harvard Medical School, Boston, Massachusetts
| | - Nicola Tolliday
- The Broad Institute of MIT and Harvard, Cambridge, Massachusetts
| | - Renee Thibodeau
- Division of Dermatology, Department of Medicine, University of Washington, Seattle, Washington
| | - Heather Sloan
- Division of Dermatology, Department of Medicine, University of Washington, Seattle, Washington
| | - Kay M Brummond
- University of Pittsburgh Center for Chemical Methodologies and Library Development, Pittsburgh, Pennsylvania
| | - Paul Nghiem
- Division of Dermatology, Department of Medicine, University of Washington, Seattle, Washington. Clinical Research Division, Fred Hutchinson Cancer Research Center, Seattle, Washington.
| |
Collapse
|
39
|
Chen T, Sun Y, Ji P, Kopetz S, Zhang W. Topoisomerase IIα in chromosome instability and personalized cancer therapy. Oncogene 2014; 34:4019-31. [PMID: 25328138 PMCID: PMC4404185 DOI: 10.1038/onc.2014.332] [Citation(s) in RCA: 125] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2014] [Revised: 09/08/2014] [Accepted: 09/08/2014] [Indexed: 12/29/2022]
Abstract
Genome instability is a hallmark of cancer cells. Chromosome instability (CIN), which is often mutually exclusive from hypermutation genotypes, represents a distinct subtype of genome instability. Hypermutations in cancer cells are due to defects in DNA repair genes, but the cause of CIN is still elusive. However, because of the extensive chromosomal abnormalities associated with CIN, its cause is likely a defect in a network of genes that regulate mitotic checkpoints and chromosomal organization and segregation. Emerging evidence has shown that the chromosomal decatenation checkpoint, which is critical for chromatin untangling and packing during genetic material duplication, is defective in cancer cells with CIN. The decatenation checkpoint is known to be regulated by a family of enzymes called topoisomerases. Among them, the gene encoding topoisomerase IIα (TOP2A) is commonly altered at both gene copy number and gene expression level in cancer cells. Thus, abnormal alterations of TOP2A, its interacting proteins, and its modifications may play a critical role in CIN in human cancers. Clinically, a large arsenal of topoisomerase inhibitors have been used to suppress DNA replication in cancer. However, they often lead to the secondary development of leukemia because of their effect on the chromosomal decatenation checkpoint. Therefore, topoisomerase drugs must be used judiciously and administered on an individual basis. In this review, we highlight the biological function of TOP2A in chromosome segregation and the mechanisms that regulate this enzyme's expression and activity. We also review the roles of TOP2A and related proteins in human cancers, and raise a perspective for how to target TOP2A in personalized cancer therapy.
Collapse
Affiliation(s)
- T Chen
- 1] Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA [2] Department of Endoscopy Center, Zhongshan Hospital, Fudan University, Shanghai, China
| | - Y Sun
- Department of Pathology, Tianjin Medical University Cancer Institute and Hospital, Tianjin, China
| | - P Ji
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - S Kopetz
- Department of Gastrointestinal Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| | - W Zhang
- Department of Pathology, The University of Texas MD Anderson Cancer Center, Houston, TX, USA
| |
Collapse
|
40
|
Hirota K, Tsuda M, Murai J, Takagi T, Keka IS, Narita T, Fujita M, Sasanuma H, Kobayashi J, Takeda S. SUMO-targeted ubiquitin ligase RNF4 plays a critical role in preventing chromosome loss. Genes Cells 2014; 19:743-54. [PMID: 25205350 DOI: 10.1111/gtc.12173] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2014] [Accepted: 07/26/2014] [Indexed: 01/08/2023]
Abstract
RING finger protein 4 (RNF4) represents a subclass of ubiquitin ligases that target proteins modified by the small ubiquitin-like modifier (SUMO) for ubiquitin-mediated degradation. We disrupted the RNF4 gene in chicken DT40 cells and found that the resulting RNF4(-/-) cells gradually lost proliferation capability. Strikingly, this compromised proliferation was associated with an unprecedented cellular effect: the gradual decrease in the number of intact chromosomes. In the 6 weeks after gene targeting, there was a 25% reduction in the DNA content of the RNF4(-/-) cells. Regarding trisomic chromosome 2, 60% of the RNF4(-/-) cells lost one homologue, suggesting that DNA loss was mediated by whole chromosome loss. To determine the cause of this chromosome loss, we examined cell-cycle checkpoint pathways. RNF4(-/-) cells showed a partial defect in the spindle assembly checkpoint, premature dissociation of sister chromatids, and a marked increase in the number of lagging chromosomes at anaphase. Thus, combined defects in SAC and sister chromatid cohesion may result in increased lagging chromosomes, leading to chromosome loss without accompanying chromosome gain in RNF4(-/-) cells. We therefore propose that RNF4 plays a novel role in preventing the loss of intact chromosomes and ensures the maintenance of chromosome integrity.
Collapse
Affiliation(s)
- Kouji Hirota
- Department of Radiation Genetics, Graduate School of Medicine, Kyoto University, Yoshidakonoe, Sakyo-ku, Kyoto, 606-8501, Japan; Department of Chemistry, Graduate School of Science and Engineering, Tokyo Metropolitan University, Minamiosawa 1-1, Hachioji-shi, Tokyo, 192-0397, Japan
| | | | | | | | | | | | | | | | | | | |
Collapse
|
41
|
Brooks K, Ranall M, Spoerri L, Stevenson A, Gunasingh G, Pavey S, Meunier F, Gonda TJ, Gabrielli B. Decatenation checkpoint-defective melanomas are dependent on PI3K for survival. Pigment Cell Melanoma Res 2014; 27:813-21. [DOI: 10.1111/pcmr.12268] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2014] [Accepted: 05/25/2014] [Indexed: 01/21/2023]
Affiliation(s)
- Kelly Brooks
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| | - Max Ranall
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| | - Loredana Spoerri
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| | - Alex Stevenson
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| | - Gency Gunasingh
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| | - Sandra Pavey
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| | - Fred Meunier
- Clem Jones Centre for Ageing Dementia Research; Queensland Brain Institute; The University of Queensland; Brisbane Qld Australia
| | - Thomas J. Gonda
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| | - Brian Gabrielli
- Translational Research Institute; The University of Queensland Diamantina Institute; Brisbane Qld Australia
| |
Collapse
|
42
|
Gu Y, Yu Y, Ai L, Shi J, Liu X, Sun H, Liu Y. Association of the ATM gene polymorphisms with papillary thyroid cancer. Endocrine 2014; 45:454-61. [PMID: 23925578 DOI: 10.1007/s12020-013-0020-1] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/24/2013] [Accepted: 07/18/2013] [Indexed: 01/02/2023]
Abstract
Papillary thyroid cancer (PTC) is the most common type of thyroid cancer, yet few genetic markers of PTC risk useful for screening exist. Our study aimed to evaluate the association between single nucleotide polymorphisms (SNPs) of the ataxia telangiectasia mutated (ATM) gene and PTC risk. 358 patients with PTC and 360 healthy controls were included in the case-control study. Four ATM SNPs (rs664677, rs373759, rs4988099, and rs189037) were genotyped by matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The analysis of genetic data was performed using the SNPStats program. The allele frequencies and genotype distributions of the four ATM SNPs were not different between PTC patients and controls. We did not observe any tendency of increasing the frequency of the risk allele from controls, patients without metastasis to patients with metastasis (P(trend) > 0.05). Interestingly, the AG genotype of rs373759 was associated with PTC risk under an overdominant model of inheritance (adjusted OR = 1.38; 95 % CI, 1.03-1.87; P = 0.03). No haplotype was observed to be significantly associated with PTC risk. Our results suggest that heterozygosity for the ATM rs373759 polymorphism may be a potential risk factor for PTC.
Collapse
Affiliation(s)
- Yulu Gu
- Department of Epidemiology and Biostatistics, School of Public Health, Jilin University, Changchun, 130021, China
| | | | | | | | | | | | | |
Collapse
|
43
|
Malki A, Ashry ESE. Quinuclidinone derivative 6 induced apoptosis in human breast cancer cells via sphingomyelinase and JNK signaling. J Chemother 2013. [DOI: 10.1179/1973947812y.0000000035] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/31/2022]
|
44
|
Choy JS, O'Toole E, Schuster BM, Crisp MJ, Karpova TS, McNally JG, Winey M, Gardner MK, Basrai MA. Genome-wide haploinsufficiency screen reveals a novel role for γ-TuSC in spindle organization and genome stability. Mol Biol Cell 2013; 24:2753-63. [PMID: 23825022 PMCID: PMC3756926 DOI: 10.1091/mbc.e12-12-0902] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2012] [Revised: 06/19/2013] [Accepted: 06/24/2013] [Indexed: 02/02/2023] Open
Abstract
How subunit dosage contributes to the assembly and function of multimeric complexes is an important question with implications in understanding biochemical, evolutionary, and disease mechanisms. Toward identifying pathways that are susceptible to decreased gene dosage, we performed a genome-wide screen for haploinsufficient (HI) genes that guard against genome instability in Saccharomyces cerevisiae. This led to the identification of all three genes (SPC97, SPC98, and TUB4) encoding the evolutionarily conserved γ-tubulin small complex (γ-TuSC), which nucleates microtubule assembly. We found that hemizygous γ-TuSC mutants exhibit higher rates of chromosome loss and increases in anaphase spindle length and elongation velocities. Fluorescence microscopy, fluorescence recovery after photobleaching, electron tomography, and model convolution simulation of spc98/+ mutants revealed improper regulation of interpolar (iMT) and kinetochore (kMT) microtubules in anaphase. The underlying cause is likely due to reduced levels of Tub4, as overexpression of TUB4 suppressed the spindle and chromosome segregation defects in spc98/+ mutants. We propose that γ-TuSC is crucial for balanced assembly between iMTs and kMTs for spindle organization and accurate chromosome segregation. Taken together, the results show how gene dosage studies provide critical insights into the assembly and function of multisubunit complexes that may not be revealed by using traditional studies with haploid gene deletion or conditional alleles.
Collapse
Affiliation(s)
- John S. Choy
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Eileen O'Toole
- Department of Cellular and Developmental Biology, University of Colorado–Boulder, Boulder, CO 80309
| | - Breanna M. Schuster
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455
| | - Matthew J. Crisp
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Tatiana S. Karpova
- Fluorescent Imaging Facility, Laboratory of Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - James G. McNally
- Fluorescent Imaging Facility, Laboratory of Receptor Biology and Gene Expression, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| | - Mark Winey
- Department of Cellular and Developmental Biology, University of Colorado–Boulder, Boulder, CO 80309
| | - Melissa K. Gardner
- Department of Genetics, Cell Biology and Development, University of Minnesota, Minneapolis, MN 55455
| | - Munira A. Basrai
- Genetics Branch, Center for Cancer Research, National Cancer Institute, Bethesda, MD 20892
| |
Collapse
|
45
|
Abstract
Research shows that cancers are recognized by the immune system but that the immune recognition of tumors does not uniformly result in tumor rejection or regression. Quantitating the success or failure of the immune system in tumor elimination is difficult because we do not really know the total numbers of encounters of the immune system with the tumors. Regardless of that important issue, recognition of the tumor by the immune system implicitly contains the idea of the tumor antigen, which is what is actually recognized. We review the molecular identity of all forms of tumor antigens (antigens with specific mutations, cancer-testis antigens, differentiation antigens, over-expressed antigens) and discuss the use of these multiple forms of antigens in experimental immunotherapy of mouse and human melanoma. These efforts have been uniformly unsuccessful; however, the approaches that have not worked or have somewhat worked have been the source of many new insights into melanoma immunology. From a critical review of the various approaches to vaccine therapy we conclude that individual cancer-specific mutations are truly the only sources of cancer-specific antigens, and therefore, the most attractive targets for immunotherapy.
Collapse
Affiliation(s)
- Tatiana Blanchard
- Department of Immunology, and Carole and Ray Neag Comprehensive Cancer Center, University of Connecticut School of Medicine, Farmington, CT 06030-1601, USA
| | | | | |
Collapse
|
46
|
Mukherjee JJ, Kumar S. DNA synthesis inhibition in response to benzo[a]pyrene dihydrodiol epoxide is associated with attenuation of p(34)cdc2: Role of p53. Mutat Res 2013; 755:61-7. [PMID: 23692869 PMCID: PMC3743414 DOI: 10.1016/j.mrgentox.2013.05.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2013] [Revised: 05/09/2013] [Accepted: 05/13/2013] [Indexed: 04/21/2023]
Abstract
Our previous findings demonstrated that DNA damage by polynuclear aromatic hydrocarbons (PAHs) triggers a cellular protective response of growth inhibition (G1-S cell cycle arrest and inhibition of DNA synthesis) in human fibroblasts associated with accumulation of p53 protein, a growth-inhibitory transcription factor. Here, we report that BPDE (the ultimate carcinogenic metabolite of the PAH benzo[a]pyrene) treatment triggers a variable extent of inhibition of DNA synthesis/cell growth, which does not correspond to the extent of increased p53 accumulation. BPDE treatment of cells significantly attenuates expression of p(34)cdc2, a cell cycle activating protein. Although the role of cdc2 down-regulation in inhibition of cell cycle progression is well known, cdc2 down-regulation in response to cellular insult by PAHs has not been reported. Unlike p53 accumulation, there is a correspondence between DNA synthesis/cell growth inhibition and cdc2 down-regulation by BPDE. BPDE-induced cdc2 down-regulation is p53 dependent, although there is no correspondence between p53 accumulation and cdc2 down-regulation. BPDE-induced cdc2 down-regulation corresponded with accumulation of the cell cycle inhibitor protein p21 (transactivation product of p53). DNA synthesis/cell growth inhibition in response to DNA-damaging PAHs may involve down-regulation of cdc2 protein mediated by p53 activation (transactivation ability), and the extent of p53 accumulation is not the sole determining factor in this regard.
Collapse
|
47
|
Alekseeva L, Rault L, Almeida S, Legembre P, Edmond V, Azevedo V, Miyoshi A, Even S, Taieb F, Arlot-Bonnemains Y, Le Loir Y, Berkova N. Staphylococcus aureus-induced G2/M phase transition delay in host epithelial cells increases bacterial infective efficiency. PLoS One 2013; 8:e63279. [PMID: 23717407 PMCID: PMC3662696 DOI: 10.1371/journal.pone.0063279] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2012] [Accepted: 04/02/2013] [Indexed: 12/19/2022] Open
Abstract
Staphylococcus aureus is a highly versatile, opportunistic pathogen and the etiological agent of a wide range of infections in humans and warm-blooded animals. The epithelial surface is its principal site of colonization and infection. In this work, we investigated the cytopathic effect of S. aureus strains from human and animal origins and their ability to affect the host cell cycle in human HeLa and bovine MAC-T epithelial cell lines. S. aureus invasion slowed down cell proliferation and induced a cytopathic effect, resulting in the enlargement of host cells. A dramatic decrease in the number of mitotic cells was observed in the infected cultures. Flow cytometry analysis revealed an S. aureus-induced delay in the G2/M phase transition in synchronous HeLa cells. This delay required the presence of live S. aureus since the addition of the heat-killed bacteria did not alter the cell cycle. The results of Western blot experiments showed that the G2/M transition delay was associated with the accumulation of inactive cyclin-dependent kinase Cdk1, a key inducer of mitosis entry, and with the accumulation of unphosphorylated histone H3, which was correlated with a reduction of the mitotic cell number. Analysis of S. aureus proliferation in asynchronous, G1- and G2-phase-enriched HeLa cells showed that the G2 phase was preferential for bacterial infective efficiency, suggesting that the G2 phase delay may be used by S. aureus for propagation within the host. Taken together, our results divulge the potential of S. aureus in the subversion of key cellular processes such as cell cycle progression, and shed light on the biological significance of S. aureus-induced host cell cycle alteration.
Collapse
Affiliation(s)
- Ludmila Alekseeva
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Moscow, Russian Federation
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- AGROCAMPUS OUEST, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
| | - Lucie Rault
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- AGROCAMPUS OUEST, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
| | - Sintia Almeida
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- AGROCAMPUS OUEST, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- Universidade Federal de Minas Gerais, Instituto de Ciencias Biologicas, Departamento de Biologia Geral, Belo Horizonte, Minas Gerais, Brazil
| | - Patrick Legembre
- Institut de Recherche en Santé, Environnement et Travail, U1085, Université Rennes-1, Rennes, France
| | - Valérie Edmond
- Institut de Recherche en Santé, Environnement et Travail, U1085, Université Rennes-1, Rennes, France
| | - Vasco Azevedo
- Universidade Federal de Minas Gerais, Instituto de Ciencias Biologicas, Departamento de Biologia Geral, Belo Horizonte, Minas Gerais, Brazil
| | - Anderson Miyoshi
- Universidade Federal de Minas Gerais, Instituto de Ciencias Biologicas, Departamento de Biologia Geral, Belo Horizonte, Minas Gerais, Brazil
| | - Sergine Even
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- AGROCAMPUS OUEST, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
| | - Frédéric Taieb
- Institut National de la Recherche Agronomique, USC U1043, Institut National de la Santé et de la Recherche Médicale, Toulouse, France
| | - Yannick Arlot-Bonnemains
- CNRS, Unité Mixte de Recherche 6290, Biologie, Santé, Innovation technologique, Université Rennes-1, Rennes, France
| | - Yves Le Loir
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- AGROCAMPUS OUEST, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
| | - Nadia Berkova
- Institut National de la Recherche Agronomique, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- AGROCAMPUS OUEST, Unité Mixte de Recherche 1253, Science et Technologie du Lait et de l'Œuf, Rennes, France
- * E-mail:
| |
Collapse
|
48
|
Abstract
Flow cytometry, a valuable technique that employs the principles of light scattering, light excitation, and emission of fluorochrome molecules, can be used to assess the cell cycle position of individual cells based on DNA content. After the permeabilization of cells, the DNA can be stained with a fluorescent dye. Cells which have a 2N amount of DNA can be distinguished from cells with a 4N amount of DNA, making flow cytometry a very useful tool for the analysis of cell cycle checkpoints following DNA damage. A critical feature of the cellular response to DNA damage is the ability to pause and repair the damage so that consequential mutations are not passed along to daughter generations of cells. If cells arrest prior to DNA replication, they will contain a 2N amount of DNA, whereas arrest after replication but before mitosis will result in a 4N amount of DNA. Using this technique, the role that p53 plays in cell cycle checkpoints -following DNA damage can be evaluated based on changes in the profile of the G1, S, and G2/M phases of the cell cycle.
Collapse
|
49
|
Chauffert B, Dimanche-Boitrel MT, Garrido C, Ivarsson M, Martin M, Martin F, Solary E. New insights into the kinetic resistance to anticancer agents. Cytotechnology 2012; 27:225-35. [PMID: 19002794 DOI: 10.1023/a:1008025124242] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Kinetic resistance plays a major role in the failure of chemotherapy towards many solid tumors. Kinetic resistance to cytotoxic drugs can be reproduced in vitro by growing the cells as multicellular spheroids (Multicellular Resistance) or as hyperconfluent cultures (Confluence-Dependent Resistance). Recent findings on the cell cycle regulation have permitted a better understanding why cancer cells which arrest in long quiescent phases are poorly sensitive to cell-cycle specific anticancer drugs. Two cyclin-dependent kinase inhibitors (CDKI) seem particularly involved in the cell cycle arrest at the G1 to S transition checkpoint: the p53-dependent p21(cip1) protein which is activated by DNA damage and the p27(kip1) which is a mediator of the contact inhibition signal. Cell quiescence could alter drug-induced apoptosis which is partly dependent on an active progression in the cell cycle and which is facilitated by overexpression of oncogenes such as c-Myc or cyclins. Investigations are yet necessary to determine the influence of the cell cycle on the balance between antagonizing (bcl-2, bcl-X(L)...) or stimulating (Bax, Bcl-X(S), Fas...) factors in chemotherapy-induced apoptosis. Quiescent cells could also be protected from toxic agents by an enhanced expression of stress proteins, such as HSP27 which is induced by confluence. New strategies are required to circumvent kinetic resistance of solid tumors: adequate choice of anticancer agents whose activity is not altered by quiescence (radiation, cisplatin), recruitment from G1 to S/G2 phases by cell pretreatment with alkylating drugs or attenuation of CDKI activity by specific inhibitors.
Collapse
|
50
|
Shen L, Nishioka T, Guo J, Chen C. Geminin functions downstream of p53 in K-ras-induced gene amplification of dihydrofolate reductase. Cancer Res 2012; 72:6153-62. [PMID: 23026135 DOI: 10.1158/0008-5472.can-12-1862] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
DNA strand breakage and perturbation of cell-cycle progression contribute to gene amplification events that can drive cancer. In cells lacking p53, DNA damage does not trigger an effective cell-cycle arrest and in this setting promotes gene amplification. This is also increased in cells harboring oncogenic Ras, in which cell-cycle arrest is perturbed and ROS levels that cause DNA single strand breaks are elevated. This study focused on the effects of v-K-ras and p53 on Methotrexate (MTX)-mediated DHFR amplification. Rat lung epithelial cells expressing v-K-ras or murine lung cancer LKR cells harboring active K-ras continued cell-cycle progression when treated with MTX. However, upon loss of p53, amplification of DHFR and formation of MTX-resistant colonies occurred. Expression levels of cyclin A, Geminin, and Cdt1 were increased in v-K-ras transfectants. Geminin was sufficient to prevent the occurrence of multiple replications via interaction with Cdt1 after MTX treatment, and DHFR amplification proceeded in v-K-ras transfectants that possess a functional p53 in the absence of geminin. Taken together, our findings indicate that p53 not only regulates cell-cycle progression, but also functions through geminin to prevent DHFR amplification and protect genomic integrity.
Collapse
Affiliation(s)
- Ling Shen
- Department of Radiation Oncology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, Massachusetts, USA
| | | | | | | |
Collapse
|