1
|
Datta I, Bangi E. Senescent cells and macrophages cooperate through a multi-kinase signaling network to promote intestinal transformation in Drosophila. Dev Cell 2024; 59:566-578.e3. [PMID: 38309266 PMCID: PMC10939848 DOI: 10.1016/j.devcel.2024.01.009] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2023] [Revised: 11/21/2023] [Accepted: 01/12/2024] [Indexed: 02/05/2024]
Abstract
Cellular senescence is a conserved biological process that plays a crucial and context-dependent role in cancer. The highly heterogeneous and dynamic nature of senescent cells and their small numbers in tissues make in vivo mechanistic studies of senescence challenging. As a result, how multiple senescence-inducing signals are integrated in vivo to drive senescence in only a small number of cells is unclear. Here, we identify cells that exhibit multiple features of senescence in a Drosophila model of intestinal transformation, which emerge in response to concurrent activation of AKT, JNK, and DNA damage signaling within transformed tissue. Eliminating senescent cells, genetically or by treatment with senolytic compounds, reduces overgrowth and improves survival. We find that senescent cells promote tumorigenesis by recruiting Drosophila macrophages to the transformed tissue, which results in non-autonomous activation of JNK signaling. These findings identify senescent cell-macrophage interactions as an important driver of epithelial transformation.
Collapse
Affiliation(s)
- Ishwaree Datta
- Department of Biological Science, Florida State University, Tallahassee, FL 32304, USA
| | - Erdem Bangi
- Department of Biological Science, Florida State University, Tallahassee, FL 32304, USA.
| |
Collapse
|
2
|
Park M, Ha J, Lee Y, Kwon Y, Choi SH, Kim BS, Jeong YK. BR101801 enhances the radiosensitivity of p53-deficient colorectal cancer cells by inducing G2/M arrest, apoptosis, and senescence in a p53-independent manner. Am J Cancer Res 2023; 13:5887-5900. [PMID: 38187039 PMCID: PMC10767343] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2023] [Accepted: 10/28/2023] [Indexed: 01/09/2024] Open
Abstract
Inhibition of DNA-dependent protein kinase (DNA-PK) in the non-homologous end-joining repair pathway reportedly increases the radiation sensitivity of cancer cells. We have recently reported that BR101801, a novel triple inhibitor of PI3K-gamma (γ), delta (δ), and DNA-PK, functions as an efficient sensitizer of radiation-induced DNA damage in various human solid cancer cells and a xenograft mouse model. Given that the p53 tumor suppressor gene plays an important role in radiotherapeutic efficacy, in the current study, we focused on the impact of the p53 status on BR101801-induced radiosensitization using isogenic HCT116 p53+/+ and HCT116 p53-/- human colorectal cancer cell lines. In vitro, HCT116 p53+/+ and HCT116 p53-/- human colorectal cancer cells were pretreated with 1 μM BR101801 for 24 h before exposure to ionizing radiation (IR), followed by assays to analyze colony formation, DNA damage, cell cycle changes, senescence, autophagy, apoptosis, and DNA damage response-related proteins. Xenograft mouse models were constructed to examine the potential synergistic effects of BR101801 (50 mg/kg, orally administered once daily) and fractionated IR (2 Gy × 3 days) on tumor growth inhibition in vivo. BR101801 inhibited cell proliferation and prolonged DNA damage in both HCT116 p53+/+ and HCT116 p53-/- human colorectal cancer cells. Combined treatment with BR101801 and IR robustly induced G2/M phase cell cycle arrest, apoptosis, and cellular senescence in HCT116 p53-/- cells when compared with treatment with IR alone. Furthermore, BR101801 synergistically inhibited tumor growth in the HCT116 p53-/- xenograft mouse model. BR101801 enhanced the radiosensitivity of HCT116 human colorectal cancer cells regardless of their p53 status. Moreover, BR101801 exerted robust synergistic effects on IR-induced cell cycle arrest, apoptosis, and tumor growth inhibition, even in radioresistant HCT116 p53-/- cells. Overall, these findings provide a scientific rationale for combining BR101801 with IR as a new therapeutic strategy to overcome radioresistance induced by p53 deficiency.
Collapse
Affiliation(s)
- Mijeong Park
- Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans UniversitySeoul 03760, Republic of Korea
| | - Jimin Ha
- Radiological and Medical Support Center, Korea Institute of Radiological and Medical SciencesSeoul 01812, Republic of Korea
| | - Yuri Lee
- Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans UniversitySeoul 03760, Republic of Korea
- Radiological and Medical Support Center, Korea Institute of Radiological and Medical SciencesSeoul 01812, Republic of Korea
| | - Youngjoo Kwon
- Graduate School of Pharmaceutical Sciences, College of Pharmacy, Ewha Womans UniversitySeoul 03760, Republic of Korea
| | - Sang Hyun Choi
- Research Team of Medical Physics and Engineering, Korea Institute of Radiological and Medical SciencesSeoul 01812, Republic of Korea
| | - Byoung Soo Kim
- Division of Applied RI, Korea Institute of Radiological and Medical SciencesSeoul 01812, Republic of Korea
| | - Youn Kyoung Jeong
- Radiological and Medical Support Center, Korea Institute of Radiological and Medical SciencesSeoul 01812, Republic of Korea
| |
Collapse
|
3
|
Datta I, Bangi E. Senescent cells and macrophages cooperate through a multi-kinase signaling network to promote intestinal transformation in Drosophila. bioRxiv 2023:2023.05.15.540869. [PMID: 37292988 PMCID: PMC10245684 DOI: 10.1101/2023.05.15.540869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Cellular senescence is a conserved biological process essential for embryonic development, tissue remodeling, repair, and a key regulator of aging. Senescence also plays a crucial role in cancer, though this role can be tumor-suppressive or tumor-promoting, depending on the genetic context and the microenvironment. The highly heterogeneous, dynamic, and context-dependent nature of senescence-associated features and the relatively small numbers of senescent cells in tissues makes in vivo mechanistic studies of senescence challenging. As a result, which senescence-associated features are observed in which disease contexts and how they contribute to disease phenotypes remain largely unknown. Similarly, the specific mechanisms by which various senescence-inducing signals are integrated in vivo to induce senescence and why some cells become senescent while their immediate neighbors do not are unclear. Here, we identify a small number of cells that exhibit multiple features of senescence in a genetically complex model of intestinal transformation we recently established in the developing Drosophila larval hindgut epithelium. We demonstrate that these cells emerge in response to concurrent activation of AKT, JNK, and DNA damage response pathways within transformed tissue. Eliminating senescent cells, genetically or by treatment with senolytic compounds, reduces overgrowth and improves survival. We find that this tumor-promoting role is mediated by Drosophila macrophages recruited to the transformed tissue by senescent cells, which results in non-autonomous activation of JNK signaling within the transformed epithelium. These findings emphasize complex cell-cell interactions underlying epithelial transformation and identify senescent cell-macrophage interactions as a potential druggable node in cancer.
Collapse
Affiliation(s)
- Ishwaree Datta
- Department of Biological Science, Florida State University, Tallahassee, FL 32304, USA
| | - Erdem Bangi
- Department of Biological Science, Florida State University, Tallahassee, FL 32304, USA
| |
Collapse
|
4
|
Wang R, Sun L, Xia S, Wu H, Ma Y, Zhan S, Zhang G, Zhang X, Shi T, Chen W. B7-H3 suppresses doxorubicin-induced senescence-like growth arrest in colorectal cancer through the AKT/TM4SF1/SIRT1 pathway. Cell Death Dis 2021; 12:453. [PMID: 33958586 PMCID: PMC8102521 DOI: 10.1038/s41419-021-03736-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2021] [Revised: 04/19/2021] [Accepted: 04/19/2021] [Indexed: 12/18/2022]
Abstract
Emerging evidence suggests that cellular senescence induced by chemotherapy has been recognized as a new weapon for cancer therapy. This study aimed to research novel functions of B7-H3 in cellular senescence induced by a low dose of doxorubicin (DOX) in colorectal cancer (CRC). Here, our results demonstrated that B7-H3 knockdown promoted, while B7-H3 overexpression inhibited, DOX-induced cellular senescence. B7-H3 knockdown dramatically enhanced the growth arrest of CRC cells after low-dose DOX treatment, but B7-H3 overexpression had the opposite effect. By RNA-seq analysis and western blot, we showed that B7-H3 prevented cellular senescence and growth arrest through the AKT/TM4SF1/SIRT1 pathway. Blocking the AKT/TM4SF1/SIRT1 pathway dramatically reversed B7-H3-induced resistance to cellular senescence. More importantly, B7-H3 inhibited DOX-induced cellular senescence of CRC cells in vivo. Therefore, targeting B7-H3 or the B7-H3/AKT/TM4SF1/SIRT1 pathway might be a new strategy for promoting cellular senescence-like growth arrest during drug treatment in CRC.
Collapse
Affiliation(s)
- Ruoqin Wang
- Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
- Department of Gastroenterology, The First Affiliated Hospital of Soochow University, 188 Shizi Road, Suzhou, China
- Jiangsu Key Laboratory of Clinical Immunology, Soochow University, 708 Renmin Road, Suzhou, China
- Suzhou Key Laboratory for Tumor Immunology of Digestive Tract, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
| | - Linqing Sun
- Department of Gastroenterology, The First Affiliated Hospital of Soochow University, 188 Shizi Road, Suzhou, China
| | - Suhua Xia
- Department of Oncology, The First Affiliated Hospital of Soochow University, 188 Shizi Road, Suzhou, China
| | - Hongya Wu
- Jiangsu Key Laboratory of Gastrointestinal Tumor Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
| | - Yanchao Ma
- Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
- Department of Gastroenterology, The First Affiliated Hospital of Soochow University, 188 Shizi Road, Suzhou, China
| | - Shenghua Zhan
- Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
| | - Guangbo Zhang
- Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
- Jiangsu Key Laboratory of Clinical Immunology, Soochow University, 708 Renmin Road, Suzhou, China
| | - Xueguang Zhang
- Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
- Jiangsu Key Laboratory of Clinical Immunology, Soochow University, 708 Renmin Road, Suzhou, China
- Jiangsu Key Laboratory of Gastrointestinal Tumor Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China
| | - Tongguo Shi
- Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China.
- Jiangsu Key Laboratory of Clinical Immunology, Soochow University, 708 Renmin Road, Suzhou, China.
- Suzhou Key Laboratory for Tumor Immunology of Digestive Tract, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China.
| | - Weichang Chen
- Jiangsu Institute of Clinical Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China.
- Department of Gastroenterology, The First Affiliated Hospital of Soochow University, 188 Shizi Road, Suzhou, China.
- Jiangsu Key Laboratory of Clinical Immunology, Soochow University, 708 Renmin Road, Suzhou, China.
- Suzhou Key Laboratory for Tumor Immunology of Digestive Tract, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China.
- Jiangsu Key Laboratory of Gastrointestinal Tumor Immunology, The First Affiliated Hospital of Soochow University, 708 Renmin Road, Suzhou, China.
| |
Collapse
|
5
|
Dutta B, Asami T, Imatomi T, Igarashi K, Nagata K, Watanabe-Asaka T, Yasuda T, Oda S, Shartl M, Mitani H. Strain difference in transgene-induced tumorigenesis and suppressive effect of ionizing radiation. J Radiat Res 2021; 62:12-24. [PMID: 33231252 PMCID: PMC7779347 DOI: 10.1093/jrr/rraa103] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/14/2019] [Revised: 01/30/2020] [Indexed: 06/11/2023]
Abstract
Transgenic expression in medaka of the Xiphophorus oncogene xmrk, under a pigment cell specific mitf promoter, induces hyperpigmentation and pigment cell tumors. In this study, we crossed the Hd-rR and HNI inbred strains because complete genome information is readily available for molecular and genetic analysis. We prepared an Hd-rR (p53+/-, p53-/-) and Hd-rR HNI hybrid (p53+/-) fish-based xmrk model system to study the progression of pigment cells from hyperpigmentation to malignant tumors on different genetic backgrounds. In all strains examined, most of the initial hyperpigmentation occurred in the posterior region. On the Hd-rR background, mitf:xmrk-induced tumorigenesis was less frequent in p53+/- fish than in p53-/- fish. The incidence of hyperpigmentation was more frequent in Hd-rR/HNI hybrids than in Hd-rR homozygotes; however, the frequency of malignant tumors was low, which suggested the presence of a tumor suppressor in HNI genetic background fish. The effects on tumorigenesis in xmrk-transgenic immature medaka of a single 1.3 Gy irradiation was assessed by quantifying tumor progression over 4 consecutive months. The results demonstrate that irradiation has a different level of suppressive effect on the frequency of hyperpigmentation in purebred Hd-rR compared with hybrids.
Collapse
Affiliation(s)
- Bibek Dutta
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Taichi Asami
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Tohru Imatomi
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Kento Igarashi
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Kento Nagata
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Tomomi Watanabe-Asaka
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Takako Yasuda
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Shoji Oda
- Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 277-8562, Kashiwa, Japan
| | - Manfred Shartl
- University of Wuerzburg, Physiological Chemistry, Biocenter, 97074 Wuerzburg, Germany and the Xiphophorus Genetic Stock Center, Department of Chemistry and Biochemistry, Texas State University, San Marcos, Texas, 78666, USA
| | - Hiroshi Mitani
- Corresponding author. Laboratory of Genome Stability, Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, 5-1-5 Kashiwanoha 277-8562, Kashiwa, Japan. Tel: +81(4) 7136-3670; Fax:+81(4)7136-3669;
| |
Collapse
|
6
|
Liang Y, Liang N, Yin L, Xiao F. Cellular and molecular mechanisms of xenobiotics-induced premature senescence. Toxicol Res (Camb) 2020; 9:669-675. [PMID: 33178427 DOI: 10.1093/toxres/tfaa073] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 08/12/2020] [Accepted: 08/24/2020] [Indexed: 01/10/2023] Open
Abstract
Premature senescence, which share common features with replicative senescence such as morphology, senescence-associated galactosidase (SA-β-gal) activity, cell cycle regulation, and gene expression, can be triggered by the exposure of various xenobiotics including environmental pollutant, peroxides, and anticancer drugs. The exact mechanisms underlying the senescence onset and stabilization are still obscure. In this review, we summarized the possible cellular and molecular mechanisms of xenobiotics-induced premature senescence, including induction of reactive oxygen species (ROS), tumor suppressors, and DNA damage; disequilibrium of calcium homeostasis; activation of transforming growth factor-β (TGF-β); and blockage of aryl hydrocarbon receptor (AHR) pathway. The deeper understanding of the molecular mechanisms underlying xenobiotics-induced senescence may shed light on new therapeutic strategies for age-related pathologies and extend healthy lifespan.
Collapse
Affiliation(s)
- Yuehui Liang
- Department of Health Toxicology, Xiangya School of Public Health, Central South University, No. 238 Shangmayuanling Road, Kaifu District, Changsha, Hunan 410078, PR China
| | - Ningjuan Liang
- Department of Health Toxicology, Xiangya School of Public Health, Central South University, No. 238 Shangmayuanling Road, Kaifu District, Changsha, Hunan 410078, PR China
| | - Lirong Yin
- Department of Health Toxicology, Xiangya School of Public Health, Central South University, No. 238 Shangmayuanling Road, Kaifu District, Changsha, Hunan 410078, PR China
| | - Fang Xiao
- Department of Health Toxicology, Xiangya School of Public Health, Central South University, No. 238 Shangmayuanling Road, Kaifu District, Changsha, Hunan 410078, PR China
| |
Collapse
|
7
|
Bojko A, Czarnecka-Herok J, Charzynska A, Dabrowski M, Sikora E. Diversity of the Senescence Phenotype of Cancer Cells Treated with Chemotherapeutic Agents. Cells 2019; 8:E1501. [PMID: 31771226 DOI: 10.3390/cells8121501] [Citation(s) in RCA: 67] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Revised: 11/19/2019] [Accepted: 11/21/2019] [Indexed: 12/29/2022] Open
Abstract
It is acknowledged that cancer cells are able to undergo senescence in response to clinically used chemotherapeutics. Moreover, recent years have provided evidence that some drugs can selectively remove senescent cells. Therefore, it is essential to properly identify and characterize senescent cells, especially when it comes to cancer. Senescence was induced in various cancer cell lines (A549, SH-SY-5Y, HCT116, MDA-MB-231, and MCF-7) following treatment with doxorubicin, irinotecan, methotrexate, 5-fluorouracil, oxaliplatin, or paclitaxel. Treatment with tested chemotherapeutics resulted in upregulation of p21 and proliferation arrest without cytotoxicity. A comparative analysis with the use of common senescence markers (i.e., morphology, SA-β-galactosidase, granularity, secretory phenotype, and the level of double-stranded DNA damage) revealed a large diversity in response to the chemotherapeutics used. The strongest senescence inducers were doxorubicin, irinotecan, and methotrexate; paclitaxel had an intermediate effect and oxaliplatin and 5-fluorouracil did not induce senescence. In addition, different susceptibility of cancer cells to senescence was observed. A statistical analysis aimed at finding any relationship between the senescence markers applied did not show clear correlations. Moreover, increased SA-β-gal activity coupled with p21 expression proved not to be an unequivocal senescence marker. This points to a need to simultaneously analyze multiple markers, given their individual limitations.
Collapse
|
8
|
Prieto I, Zambrano A, Laso J, Aranda A, Samper E, Monsalve M. Early induction of senescence and immortalization in PGC-1α-deficient mouse embryonic fibroblasts. Free Radic Biol Med 2019; 138:23-32. [PMID: 31029787 DOI: 10.1016/j.freeradbiomed.2019.04.015] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/03/2018] [Revised: 04/10/2019] [Accepted: 04/13/2019] [Indexed: 12/21/2022]
Abstract
AIMS Oxidative stress is known to induce early replicative senescence. Senescence has been proposed to work as a barrier to immortalization and tumor development. Here, we aimed to evaluate the impact of the loss of peroxisome proliferator activated receptor γ co-activator 1α (PGC-1α), a master regulator of oxidative metabolism and mitochondrial reactive oxygen species (ROS) generation, on replicative senescence and immortalization in mouse embryonic fibroblasts (MEFs). RESULTS We found that primary MEFs lacking PGC-1α showed higher levels of ROS than wild-type MEFs at all cell passages tested. The elevated production of ROS was associated with higher levels of oxidative DNA damage and the increased formation of DNA double-strand breaks. Evaluation of the induction of DNA repair systems in response to γ-radiation indicated that the loss of PGC-1α also resulted in a small but significant reduction in their activity. DNA damage induced the early activation of senescence markers, including an increase in the number of β-galactosidase-positive cells, the induction of p53 phosphorylation, and the increase in p16 and p19 protein. These changes were, however, not sufficient to reduce proliferation rates of PGC-1α-deficient MEFs at any cell passage tested. Moreover, PGC-1α-deficient cells escaped replicative senescence. INNOVATION & CONCLUSION PGC-1α plays an important role in the control of cellular senescence and immortalization.
Collapse
Affiliation(s)
- Ignacio Prieto
- Instituto de Investigaciones Biomédicas "Alberto Sols" (CSIC-UAM). Arturo Duperier 4. 28029, Madrid, Spain.
| | - Alberto Zambrano
- Unidad Funcional de Investigación en Enfermedades Crónicas (UFIEC), Instituto de Salud Carlos III. Ctra. Majadahonda-Pozuelo km 2. 28220, Madrid, Spain.
| | - Javier Laso
- Fundación Centro Nacional de Investigaciones Cardiovasculares Carlos III (CNIC). Melchor Fernández Almagro 3, 28029, Madrid, Spain.
| | - Ana Aranda
- Instituto de Investigaciones Biomédicas "Alberto Sols" (CSIC-UAM). Arturo Duperier 4. 28029, Madrid, Spain.
| | - Enrique Samper
- NIMGenetics, Genómica y Medicina S.L. Faraday, 7. 28049, Madrid, Spain.
| | - María Monsalve
- Instituto de Investigaciones Biomédicas "Alberto Sols" (CSIC-UAM). Arturo Duperier 4. 28029, Madrid, Spain.
| |
Collapse
|
9
|
Liu J, Peng L, Huang W, Li Z, Pan J, Sang L, Lu S, Zhang J, Li W, Luo Y. Balancing Between Aging and Cancer: Molecular Genetics Meets Traditional Chinese Medicine. J Cell Biochem 2017; 118:2581-2586. [DOI: 10.1002/jcb.25898] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2016] [Accepted: 01/18/2017] [Indexed: 01/23/2023]
Affiliation(s)
- Jing Liu
- Lab of Molecular Genetics of Aging and Tumor; Faculty of Medicine; Kunming University of Science and Technology; Chenggong County, Kunming Yunnan Province 650500 China
| | - Lei Peng
- Lab of Molecular Genetics of Aging and Tumor; Faculty of Medicine; Kunming University of Science and Technology; Chenggong County, Kunming Yunnan Province 650500 China
| | - Wenhui Huang
- Lab of Molecular Genetics of Aging and Tumor; Faculty of Medicine; Kunming University of Science and Technology; Chenggong County, Kunming Yunnan Province 650500 China
| | - Zhiming Li
- Institute of Medicinal Plants; Yunnan Academy of Agricultural Sciences; Kunming 650200 China
| | - Jun Pan
- Institute of Medicinal Plants; Yunnan Academy of Agricultural Sciences; Kunming 650200 China
| | - Lei Sang
- Lab of Molecular Genetics of Aging and Tumor; Faculty of Medicine; Kunming University of Science and Technology; Chenggong County, Kunming Yunnan Province 650500 China
| | - Siqian Lu
- Lab of Molecular Genetics of Aging and Tumor; Faculty of Medicine; Kunming University of Science and Technology; Chenggong County, Kunming Yunnan Province 650500 China
| | - Jihong Zhang
- Lab of Molecular Genetics of Aging and Tumor; Faculty of Medicine; Kunming University of Science and Technology; Chenggong County, Kunming Yunnan Province 650500 China
| | - Wanyi Li
- Institute of Medicinal Plants; Yunnan Academy of Agricultural Sciences; Kunming 650200 China
| | - Ying Luo
- Lab of Molecular Genetics of Aging and Tumor; Faculty of Medicine; Kunming University of Science and Technology; Chenggong County, Kunming Yunnan Province 650500 China
- Yunnan Provincial Institute of Digestive Disease; Kunming; Yunnan Province 650011 China
| |
Collapse
|
10
|
Ruan D, He J, Li CF, Lee HJ, Liu J, Lin HK, Chan CH. Skp2 deficiency restricts the progression and stem cell features of castration-resistant prostate cancer by destabilizing Twist. Oncogene. 2017;36:4299-4310. [PMID: 28346424 PMCID: PMC5532065 DOI: 10.1038/onc.2017.64] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Revised: 02/08/2017] [Accepted: 02/08/2017] [Indexed: 12/13/2022]
Abstract
Castration-resistant prostate cancer (CRPC) remains a major clinical challenge because of the lack of effective targeted therapy for its treatment. The mechanism underlying how CRPC gains resistance toward hormone depletion and other forms of chemotherapy is poorly understood. Research on understanding the factors that drive these processes is desperately needed to generate new therapies to cure the disease. Here, we discovered a fundamental role of S-phase protein kinase 2 (Skp2) in the formation and progression of CRPC. In transgenic adenocarcinoma mouse prostate model, Skp2 depletion leads to a profound repression of prostate tumor growth and distal metastasis and substantially prolonged overall survival. We revealed that Skp2 regulates CRPC through Twist-mediated oncogenic functions including epithelial-mesenchymal transition (EMT) and cancer stem cell (CSC) acquisitions. Mechanistically, Skp2 interacted with Twist and promoted the non-degradative ubiquitination of Twist. Consequently, Skp2 stabilized Twist protein expression by preventing proteasomal degradation of Twist by β-TrCP. We found that Twist overexpression augments CSC self-renewal and population and that Skp2 inhibition reverts Twist's effects on CSC regulation. Furthermore, genetically depleting or pharmacologically inactivating Skp2 synergistically re-sensitized CRPC cells toward chemotherapies such as paclitaxel or doxorubicin. Together, this study uncovering Skp2-mediated Twist stabilization and oncogenic functions in CRPC offers new knowledge on how CRPC progresses and acquires chemoresistance during tumor progression. It provides proof of principle that Skp2 targeting is a promising approach to combat metastatic CRPC by targeting Twist and CSCs.
Collapse
|
11
|
Brodská B, Holoubek A, Otevřelová P, Kuželová K. Low-Dose Actinomycin-D Induces Redistribution of Wild-Type and Mutated Nucleophosmin Followed by Cell Death in Leukemic Cells. J Cell Biochem 2015; 117:1319-29. [PMID: 26505272 DOI: 10.1002/jcb.25420] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2015] [Accepted: 10/26/2015] [Indexed: 11/12/2022]
Abstract
Specific mutations involving C-terminal part of the nucleolar protein nucleophosmin (NPM) are associated with better outcome of acute myeloid leukemia (AML) therapy, possibly due to aberrant cytoplasmic NPM localization facilitating induction of anti-NPM immune response. Actinomycin D (actD) is known to induce nucleolar stress leading to redistribution of many nucleolar proteins, including NPM. We analyzed the distribution of both wild-type and mutated NPM (NPMmut) in human cell lines, before and after low-dose actD treatment, in living cells expressing exogenous fluorescently labeled proteins as well as using immunofluorescence staining of endogenous proteins in fixed cells. The wild-type NPM form is prevalently nucleolar in intact cells and relocalizes mainly to the nucleoplasm following actD addition. The mutated NPM form is found both in the nucleoli and in the cytoplasm of untreated cells. ActD treatment leads to a marked increase in NPMmut amount in the nucleoplasm while a mild decrease is observed in the cytoplasm. Cell death was induced by low-dose actD in all the studied leukemic cell lines with different p53 and NPM status. In cells expressing the tumor suppresor p53 (CML-T1, OCI-AML3), cell cycle arrest in G1/G0 phase was followed by p53-dependent apoptosis while in p53-null HL60 cells, transient G2/M-phase arrest was followed by cell necrosis. We conclude that although actD does not increase NPM concentration in the cytoplasm, it could improve the effect of standard chemotherapy in leukemias through more general mechanisms.
Collapse
Affiliation(s)
- Barbora Brodská
- Department of Proteomics, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| | - Aleš Holoubek
- Department of Proteomics, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| | - Petra Otevřelová
- Department of Proteomics, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| | - Kateřina Kuželová
- Department of Proteomics, Institute of Hematology and Blood Transfusion, U Nemocnice 1, 128 20 Prague 2, Czech Republic
| |
Collapse
|
12
|
Succoio M, Comegna M, D'Ambrosio C, Scaloni A, Cimino F, Faraonio R. Proteomic analysis reveals novel common genes modulated in both replicative and stress-induced senescence. J Proteomics 2015. [DOI: 10.1016/j.jprot.2015.07.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
|
13
|
Abstract
Orphan receptors comprise nearly half of all members of the nuclear receptor superfamily. Despite having broad structural similarities to the classical estrogen receptors, estrogen-related receptors (ERRs) have their own unique DNA response elements and functions. In this study, we focus on 2 ERRβ splice variants, short form ERRβ (ERRβsf) and ERRβ2, and identify their differing roles in cell cycle regulation. Using DY131 (a synthetic agonist of ERRβ), splice-variant selective shRNA, and exogenous ERRβsf and ERRβ2 cDNAs, we demonstrate the role of ERRβsf in mediating the G1 checkpoint through p21. We also show ERRβsf is required for DY131-induced cellular senescence. A key novel finding of this study is that ERRβ2 can mediate a G2/M arrest in response to DY131. In the absence of ERRβ2, the DY131-induced G2/M arrest is reversed, and this is accompanied by p21 induction and a G1 arrest. This study illustrates novel functions for ERRβ splice variants and provides evidence for splice variant interaction.
Collapse
Affiliation(s)
- Mary Mazzotta Heckler
- a Lombardi Comprehensive Cancer Center; the Department of Oncology ; Georgetown University School of Medicine ; Washington , DC USA
| | | |
Collapse
|
14
|
Chan CH, Jo U, Kohrman A, Rezaeian AH, Chou PC, Logothetis C, Lin HK. Posttranslational regulation of Akt in human cancer. Cell Biosci 2014; 4:59. [PMID: 25309720 DOI: 10.1186/2045-3701-4-59] [Citation(s) in RCA: 101] [Impact Index Per Article: 10.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/25/2014] [Accepted: 09/04/2014] [Indexed: 12/19/2022] Open
Abstract
Akt regulates critical cellular processes including cell survival and proliferation, glucose metabolism, cell migration, cancer progression and metastasis through phosphorylation of a variety of downstream targets. The Akt pathway is one of the most prevalently hyperactivated signaling pathways in human cancer, thus, research deciphering molecular mechanisms which underlie the aberrant Akt activation has received enormous attention. The PI3K-dependent Akt serine/threonine phosphorylation by PDK1 and mTORC2 has long been thought to be the primary mechanism accounting for Akt activation. However, this regulation alone does not sufficiently explain how Akt hyperactivation can occur in tumors with normal levels of PI3K/PTEN activity. Mounting evidence demonstrates that aberrant Akt activation can be attributed to other posttranslational modifications, which include tyrosine phosphorylation, O-GlcNAcylation, as well as lysine modifications: ubiquitination, SUMOylation and acetylation. Among them, K63-linked ubiquitination has been shown to be a critical step for Akt signal activation by facilitating its membrane recruitment. Deficiency of E3 ligases responsible for growth factor-induced Akt activation leads to tumor suppression. Therefore, a comprehensive understanding of posttranslational modifications in Akt regulation will offer novel strategies for cancer therapy.
Collapse
|
15
|
Chuang HC, Yang LP, Fitzgerald AL, Osman A, Woo SH, Myers JN, Skinner HD. The p53-reactivating small molecule RITA induces senescence in head and neck cancer cells. PLoS One 2014; 9:e104821. [PMID: 25119136 PMCID: PMC4132078 DOI: 10.1371/journal.pone.0104821] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2014] [Accepted: 07/16/2014] [Indexed: 12/19/2022] Open
Abstract
TP53 is the most commonly mutated gene in head and neck cancer (HNSCC), with mutations being associated with resistance to conventional therapy. Restoring normal p53 function has previously been investigated via the use of RITA (reactivation of p53 and induction of tumor cell apoptosis), a small molecule that induces a conformational change in p53, leading to activation of its downstream targets. In the current study we found that RITA indeed exerts significant effects in HNSCC cells. However, in this model, we found that a significant outcome of RITA treatment was accelerated senescence. RITA-induced senescence in a variety of p53 backgrounds, including p53 null cells. Also, inhibition of p53 expression did not appear to significantly inhibit RITA-induced senescence. Thus, this phenomenon appears to be partially p53-independent. Additionally, RITA-induced senescence appears to be partially mediated by activation of the DNA damage response and SIRT1 (Silent information regulator T1) inhibition, with a synergistic effect seen by combining either ionizing radiation or SIRT1 inhibition with RITA treatment. These data point toward a novel mechanism of RITA function as well as hint to its possible therapeutic benefit in HNSCC.
Collapse
Affiliation(s)
- Hui-Ching Chuang
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Department of Otolaryngology, Kaohsiung Chang Gung Memorial Hospital and Chang Gung University College of Medicine, Kaohsiung, Taiwan
| | - Liang Peng Yang
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Alison L. Fitzgerald
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Abdullah Osman
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Sang Hyeok Woo
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Jeffrey N. Myers
- Department of Head and Neck Surgery, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- Graduate School of Biomedical Sciences, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
| | - Heath D. Skinner
- Department of Radiation Oncology, The University of Texas MD Anderson Cancer Center, Houston, Texas, United States of America
- * E-mail:
| |
Collapse
|
16
|
Honoki K, Tsujiuchi T. Senescence bypass in mesenchymal stem cells: a potential pathogenesis and implications of pro-senescence therapy in sarcomas. Expert Rev Anticancer Ther 2014; 13:983-96. [PMID: 23984899 DOI: 10.1586/14737140.2013.820010] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Cellular senescence is a mechanism that limits the lifespan of somatic cells as the results of replicative proliferation and response to stresses, and that prevents undesired oncogenic changes constituting a barrier against immortalization and tumorigenesis. Mesenchymal stem cells (MSCs) reside in a variety of tissues, and participates in tissue maintenance with their multipotent differentiation ability. MSCs are also considered to be as cells of origin for certain type of sarcomas. We reviewed the mechanisms of cellular senescence in MSCs and hypothesized senescence bypass as the potential pathogenesis for sarcoma development, and proposed the possibility of senescence induction therapy for an alternative treatment strategy against sarcomas, especially cells with the resistance to conventional chemo and radiotherapy including sarcoma stem cells.
Collapse
Affiliation(s)
- Kanya Honoki
- Department of Orthopedic Surgery, Nara Medical University, 840 Shijo-cho, Kashihara 634-8521, Japan.
| | | |
Collapse
|
17
|
Chan CH, Morrow JK, Li CF, Gao Y, Jin G, Moten A, Stagg LJ, Ladbury JE, Cai Z, Xu D, Logothetis CJ, Hung MC, Zhang S, Lin HK. Pharmacological inactivation of Skp2 SCF ubiquitin ligase restricts cancer stem cell traits and cancer progression. Cell 2013; 154:556-68. [PMID: 23911321 DOI: 10.1016/j.cell.2013.06.048] [Citation(s) in RCA: 302] [Impact Index Per Article: 27.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2012] [Revised: 03/20/2013] [Accepted: 06/27/2013] [Indexed: 01/19/2023]
Abstract
Skp2 E3 ligase is overexpressed in numerous human cancers and plays a critical role in cell-cycle progression, senescence, metabolism, cancer progression, and metastasis. In the present study, we identified a specific Skp2 inhibitor using high-throughput in silico screening of large and diverse chemical libraries. This Skp2 inhibitor selectively suppresses Skp2 E3 ligase activity, but not activity of other SCF complexes. It also phenocopies the effects observed upon genetic Skp2 deficiency, such as suppressing survival and Akt-mediated glycolysis and triggering p53-independent cellular senescence. Strikingly, we discovered a critical function of Skp2 in positively regulating cancer stem cell populations and self-renewal ability through genetic and pharmacological approaches. Notably, Skp2 inhibitor exhibits potent antitumor activities in multiple animal models and cooperates with chemotherapeutic agents to reduce cancer cell survival. Our study thus provides pharmacological evidence that Skp2 is a promising target for restricting cancer stem cell and cancer progression.
Collapse
|
18
|
Maqsood MI, Matin MM, Bahrami AR, Ghasroldasht MM. Immortality of cell lines: challenges and advantages of establishment. Cell Biol Int 2013; 37:1038-45. [PMID: 23723166 DOI: 10.1002/cbin.10137] [Citation(s) in RCA: 100] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2012] [Accepted: 05/02/2013] [Indexed: 12/29/2022]
Abstract
Cellular immortality happens upon impairment of cell-cycle checkpoint pathways (p53/p16/pRb), reactivation or up-regulation of telomerase enzyme, or upregulation of some oncogenes or oncoproteins leading to a higher rate of cell division.There are also some other factors and mechanisms involved in immortalisation, which need to be discovered. Immortalisation of cells derived from different sources and establishment of immortal cell lines has proven useful in understanding the molecular pathways governing cell developmental cascades in eukaryotic, especially human, cells. After the breakthrough of achieving the immortal cells and understanding their critical importance in the field of molecular biology, intense efforts have been dedicated to establish cell lines useful for elucidating the functions of telomerase, developmental lineage of progenitors, self-renewal potency, cellular transformation, differentiation patterns and some bioprocesses, like odontogenesis. Meanwhile, discovering the exact mechanisms of immortality, a major challenge for science yet, is believed to open new gateways toward understanding and treatment of cancer in the long term. This review summarises the methods involved in establishing immortality, its advantages and the challenges still being faced in this field.
Collapse
Affiliation(s)
- Muhammad Irfan Maqsood
- Department of Biology, Faculty of Science, Ferdowsi University of Mashhad, Mashhad, Iran
| | | | | | | |
Collapse
|
19
|
Zou ZJ, Zhang R, Fan L, Wang L, Fang C, Zhang LN, Yang S, Li YY, Li JY, Xu W. Low expression level of phosphatase and tensin homolog deleted on chromosome ten predicts poor prognosis in chronic lymphocytic leukemia. Leuk Lymphoma 2012; 54:1159-64. [DOI: 10.3109/10428194.2012.733880] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
|
20
|
Chan CH, Li CF, Yang WL, Gao Y, Lee SW, Feng Z, Huang HY, Tsai KKC, Flores LG, Shao Y, Hazle JD, Yu D, Wei W, Sarbassov D, Hung MC, Nakayama KI, Lin HK. The Skp2-SCF E3 ligase regulates Akt ubiquitination, glycolysis, herceptin sensitivity, and tumorigenesis. Cell 2012; 149:1098-111. [PMID: 22632973 DOI: 10.1016/j.cell.2012.02.065] [Citation(s) in RCA: 295] [Impact Index Per Article: 24.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2011] [Revised: 01/06/2012] [Accepted: 02/28/2012] [Indexed: 10/28/2022]
Abstract
Akt kinase plays a central role in cell growth, metabolism, and tumorigenesis. The TRAF6 E3 ligase orchestrates IGF-1-mediated Akt ubiquitination and activation. Here, we show that Akt ubiquitination is also induced by activation of ErbB receptors; unexpectedly, and in contrast to IGF-1 induced activation, the Skp2 SCF complex, not TRAF6, is a critical E3 ligase for ErbB-receptor-mediated Akt ubiquitination and membrane recruitment in response to EGF. Skp2 deficiency impairs Akt activation, Glut1 expression, glucose uptake and glycolysis, and breast cancer progression in various tumor models. Moreover, Skp2 overexpression correlates with Akt activation and breast cancer metastasis and serves as a marker for poor prognosis in Her2-positive patients. Finally, Skp2 silencing sensitizes Her2-overexpressing tumors to Herceptin treatment. Our study suggests that distinct E3 ligases are utilized by diverse growth factors for Akt activation and that targeting glycolysis sensitizes Her2-positive tumors to Herceptin treatment.
Collapse
Affiliation(s)
- Chia-Hsin Chan
- Department of Molecular and Cellular Oncology, The University of Texas MD Anderson Cancer Center, Houston, TX 77030, USA
| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | |
Collapse
|
21
|
Jin X, Eroglu B, Cho W, Yamaguchi Y, Moskophidis D, Mivechi NF. Inactivation of heat shock factor Hsf4 induces cellular senescence and suppresses tumorigenesis in vivo. Mol Cancer Res 2012; 10:523-34. [PMID: 22355043 DOI: 10.1158/1541-7786.mcr-11-0530] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Studies suggest that Hsf4 expression correlates with its role in cell growth and differentiation. However, the role of Hsf4 in tumorigenesis in vivo remains unexplored. In this article, we provide evidence that absence of the Hsf4 gene suppresses evolution of spontaneous tumors arising in p53- or Arf-deficient mice. Furthermore, deletion of hsf4 alters the tumor spectrum by significantly inhibiting development of lymphomas that are normally observed in the majority of mice lacking p53 or Arf tumor suppressor genes. Using mouse embryo fibroblasts deficient in the hsf4 gene, we have found that these cells exhibit reduced proliferation that is associated with induction of senescence and senescence-associated β-galactosidase (SA-β-gal). Cellular senescence in hsf4-deficient cells is associated with the increased expression of the cyclin-dependent kinase inhibitors, p21 and p27 proteins. Consistent with the cellular senescence observed in vitro, specific normal tissues of hsf4(-/-) mice and tumors that arose in mice deficient in both hsf4 and p53 genes exhibit increased SA-β-gal activity and elevated levels of p27 compared with wild-type mice. These results suggest that hsf4 deletion-induced senescence is also present in vivo. Our results therefore indicate that Hsf4 is involved in modulation of cellular senescence, which can be exploited during cancer therapy.
Collapse
Affiliation(s)
- Xiongjie Jin
- Charlie Norwood VA Medical Center, Georgia Health Sciences University, Augusta, Georgia 30912, USA
| | | | | | | | | | | |
Collapse
|
22
|
Wu J, Lee SW, Zhang X, Han F, Kwan SY, Yuan X, Yang WL, Jeong YS, Rezaeian AH, Gao Y, Zeng YX, Lin HK. Foxo3a transcription factor is a negative regulator of Skp2 and Skp2 SCF complex. Oncogene 2013; 32:78-85. [PMID: 22310285 DOI: 10.1038/onc.2012.26] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Skp2 (S-phase kinase-associated protein-2) SCF complex displays E3 ligase activity and oncogenic activity by regulating protein ubiquitination and degradation, in turn regulating cell cycle entry, senescence and tumorigenesis. The maintenance of the integrity of Skp2 SCF complex is critical for its E3 ligase activity. The Skp2 F-box protein is a rate-limiting step and key factor in this complex, which binds to its protein substrates and triggers ubiquitination and degradation of its substrates. Skp2 is found to be overexpressed in numerous human cancers, which has an important role in tumorigenesis. The molecular mechanism by which the function of Skp2 and Skp2 SCF complex is regulated remains largely unknown. Here we show that Foxo3a transcription factor is a novel and negative regulator of Skp2 SCF complex. Foxo3a is found to be a transcriptional repressor of Skp2 gene expression by directly binding to the Skp2 promoter, thereby inhibiting Skp2 protein expression. Surprisingly, we found for the first time that Foxo3a also displays a transcription-independent activity by directly interacting with Skp2 and disrupting Skp2 SCF complex formation, in turn inhibiting Skp2 SCF E3 ligase activity and promoting p27 stability. Finally, we show that the oncogenic activity of Skp2 is repressed by Foxo3a overexpression. Our results not only reveal novel insights into how Skp2 SCF complex is regulated, but also establish a new role for Foxo3a in tumor suppression through a transcription-dependent and independent manner.
Collapse
|
23
|
Abstract
How the Human T lymphotropic virus type 1 (HTLV-1) Tax protein stimulates proliferation while triggering cell cycle arrest and senescence remains puzzling. There is also a debate about the ability of Tax to activate or inhibit the DNA damage response. Here, we comment on these different activities and propose a conceptual rationale for the apparently conflicting observations.
Collapse
Affiliation(s)
- Mathieu Boxus
- National Fund for Scientific Research, Gembloux Agro-Bio Tech and Interdisciplinary Cluster for Applied Genoproteomics (GIGA), University of Liège, Belgium
| | | |
Collapse
|