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Zhang X, Wang J, Tang K, Yang Y, Liu X, Yuan S, Guo F, Zhang L, Ma K. The cell cycle regulator p16 promotes tumor infiltrated CD8 + T cell exhaustion and apoptosis. Cell Death Dis 2024; 15:339. [PMID: 38750022 PMCID: PMC11096187 DOI: 10.1038/s41419-024-06721-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2023] [Revised: 05/02/2024] [Accepted: 05/03/2024] [Indexed: 05/18/2024]
Abstract
The therapeutic efficacy of adoptive T cell therapy is largely restricted by reduced viability and dysfunction of CD8+ T cells. Continuous antigen stimulation disrupts the expansion, effector function, and metabolic fitness of CD8+ T cells, leading to their differentiation into an exhausted state within the tumor microenvironment (TME). While the function of the cell cycle negative regulator p16 in senescent cells is well understood, its role in T cell exhaustion remains unclear. In this study, we demonstrated that TCR stimulation of CD8+ T cells rapidly upregulates p16 expression, with its levels positively correlating with TCR affinity. Chronic TCR stimulation further increased p16 expression, leading to CD8+ T cell apoptosis and exhaustion differentiation, without inducing DNA damage or cell senescence. Mechanistic investigations revealed that p16 downregulates mTOR, glycolysis, and oxidative phosphorylation (OXPHOS) associated gene expression, resulting in impaired mitochondrial fitness, reduced T cell viability, and diminished effector function. Furthermore, the deletion of p16 significantly enhances the persistence of CD8+ T cells within tumors and suppresses the terminal exhaustion of tumor-infiltrating T cells. Overall, our findings elucidate how increased p16 expression reshapes T cell intracellular metabolism, drives T cell apoptosis and exhaustion differentiation, and ultimately impairs T cell anti-tumor function.
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Affiliation(s)
- Xin Zhang
- National Key Laboratory of Immunity and Inflammation, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Suzhou, Jiangsu, China
- Key Laboratory of Synthetic Biology Regulatory Element, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, China
- Institute of Pharmaceutical Sciences, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Jiajia Wang
- National Key Laboratory of Immunity and Inflammation, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Suzhou, Jiangsu, China
- Key Laboratory of Synthetic Biology Regulatory Element, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, China
| | - Kun Tang
- National Key Laboratory of Immunity and Inflammation, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Suzhou, Jiangsu, China
- Key Laboratory of Synthetic Biology Regulatory Element, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, China
- Institutes of Biology and Medical Sciences (IBMS), Soochow University, Suzhou, Jiangsu, China
| | - Yu Yang
- National Key Laboratory of Immunity and Inflammation, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Suzhou, Jiangsu, China
- Key Laboratory of Synthetic Biology Regulatory Element, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, China
- Department of Oncology, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, Jiangsu, China
| | - Xiaowei Liu
- National Key Laboratory of Immunity and Inflammation, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Suzhou, Jiangsu, China
- Key Laboratory of Synthetic Biology Regulatory Element, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, China
| | - Shengtao Yuan
- Institute of Pharmaceutical Sciences, China Pharmaceutical University, Nanjing, Jiangsu, China
| | - Feng Guo
- Department of Oncology, The Affiliated Suzhou Hospital of Nanjing Medical University, Suzhou, Jiangsu, China.
| | - Lianjun Zhang
- National Key Laboratory of Immunity and Inflammation, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Suzhou, Jiangsu, China.
- Key Laboratory of Synthetic Biology Regulatory Element, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, China.
| | - Kaili Ma
- National Key Laboratory of Immunity and Inflammation, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences & Peking Union Medical College, Suzhou, Jiangsu, China.
- Key Laboratory of Synthetic Biology Regulatory Element, Suzhou Institute of Systems Medicine, Chinese Academy of Medical Sciences and Peking Union Medical College, Suzhou, China.
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2
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Han J, Wang J, Shi H, Li Q, Zhang S, Wu H, Li W, Gan L, Brown-Borg HM, Feng W, Chen Y, Zhao RC. Ultra-small polydopamine nanomedicine-enabled antioxidation against senescence. Mater Today Bio 2023; 19:100544. [PMID: 36747580 PMCID: PMC9898451 DOI: 10.1016/j.mtbio.2023.100544] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 12/31/2022] [Accepted: 01/05/2023] [Indexed: 01/22/2023] Open
Abstract
Senescence is a cellular response characterized by cells irreversibly stopping dividing and entering a state of permanent growth arrest. One of the underlying pathophysiological causes of senescence is the oxidative stress-induced damage, indicating that eliminating the reactive oxygen and nitrogen species (RONS) may be beneficial to prevent and/or alleviate senescence. Herein, we developed ultra-small polydopamine nanoparticles (UPDA NPs) with superoxide dismutase (SOD)/catalase (CAT) enzyme-mimic activities, featuring broad-spectrum RONS-scavenging capability for inducing cytoprotective effects against RONS-mediated damage. The engineered UPDA NPs can restore senescence-related renal function, tissue homeostasis, fur density, and motor ability in mice, potentially associated with the regulation of multiple genes involved in lipid metabolism, mitochondrial function, energy homeostasis, telomerase activity, neuroprotection, and inflammatory responses. Importantly, the dietary UPDA NPs can enhance the antioxidant capacity, improve the climbing ability, and prolong the lifespan of Drosophila. Notably, UPDA NPs possess excellent biocompatibility stemming from the ultra-small size, ensuring quick clearance out of the body. These findings reveal that UPDA NPs can delay aging through reducing oxidative stress and provide a paradigm and practical strategy for treating senescence and senescence-related diseases.
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Affiliation(s)
- Jiamei Han
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Jiao Wang
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Hongwei Shi
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Qian Li
- Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering, Chinese Academy of Medical Sciences, Beijing Key Laboratory of New Drug Development and Clinical Trial of Stem Cell Therapy (BZ0381), Beijing, China,Cell Energy Life Sciences Group Co. LTD, Qingdao, Shandong, China
| | - Shibo Zhang
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Hao Wu
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Wenjun Li
- School of Life Sciences, Shanghai University, Shanghai, China
| | - Linhua Gan
- Department of Neurology and National Research Center for Aging and Medicine & National Center for Neurological Disorders, State Key Laboratory of Medical Neurobiology, Huashan Hospital, Fudan University, Shanghai, China
| | - Holly M. Brown-Borg
- Department of Biomedical Sciences, School of Medicine & Health Sciences, University of North Dakota, Grand Forks, ND, USA,Corresponding author.
| | - Wei Feng
- School of Life Sciences, Shanghai University, Shanghai, China,Corresponding authors.
| | - Yu Chen
- School of Life Sciences, Shanghai University, Shanghai, China,Corresponding author.
| | - Robert Chunhua Zhao
- School of Life Sciences, Shanghai University, Shanghai, China,Institute of Basic Medical Sciences Chinese Academy of Medical Sciences, School of Basic Medicine Peking Union Medical College, Center of Excellence in Tissue Engineering, Chinese Academy of Medical Sciences, Beijing Key Laboratory of New Drug Development and Clinical Trial of Stem Cell Therapy (BZ0381), Beijing, China,Corresponding authors. School of Life Sciences, Shanghai University, Shanghai, China.
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3
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Senescence Markers in Peripheral Blood Mononuclear Cells in Amnestic Mild Cognitive Impairment and Alzheimer's Disease. Int J Mol Sci 2022; 23:ijms23169387. [PMID: 36012652 PMCID: PMC9409141 DOI: 10.3390/ijms23169387] [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: 07/13/2022] [Revised: 08/09/2022] [Accepted: 08/13/2022] [Indexed: 11/17/2022] Open
Abstract
Recent studies suggest that cellular senescence plays a role in Alzheimer’s Disease (AD) pathogenesis. We hypothesize that cellular senescence markers might be tracked in the peripheral tissues of AD patients. Senescence hallmarks, including altered metabolism, cell-cycle arrest, DNA damage response (DDR) and senescence secretory associated phenotype (SASP), were measured in peripheral blood mononuclear cells (PBMCs) of healthy controls (HC), amnestic mild cognitive impairment (aMCI) and AD patients. Senescence-associated βeta-galactosidase (SA-β-Gal) activity, G0-G1 phase cell-cycle arrest, p16 and p53 were analyzed by flow cytometry, while IL-6 and IL-8 mRNA were analyzed by qPCR, and phosphorylated H2A histone family member X (γH2AX) was analyzed by immunofluorescence. Senescent cells in the brain tissue were determined with lipofuscin staining. An increase in the number of senescent cells was observed in the frontal cortex and hippocampus of advanced AD patients. PBMCs of aMCI patients, but not in AD, showed increased SA-β-Gal compared with HCs. aMCI PBMCs also had increased IL-6 and IL8 mRNA expression and number of cells arrested at G0-G1, which were absent in AD. Instead, AD PBMCs had significantly increased p16 and p53 expression and decreased γH2Ax activity compared with HC. This study reports that several markers of cellular senescence can be measured in PBMCs of aMCI and AD patients.
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Peraza-Labrador A, Buitrago DM, Coy-Barrera E, Perdomo-Lara SJ. Antiproliferative and Pro-Apoptotic Effects of a Phenolic-Rich Extract from Lycium barbarum Fruits on Human Papillomavirus (HPV) 16-Positive Head Cancer Cell Lines. Molecules 2022; 27:molecules27113568. [PMID: 35684505 PMCID: PMC9182172 DOI: 10.3390/molecules27113568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Revised: 05/04/2022] [Accepted: 05/05/2022] [Indexed: 11/16/2022] Open
Abstract
The in vitro antiproliferative activity of a phenolic-rich extract from Lycium barbarum fruits against head and neck HPV16 squamous cell carcinoma (OSCC) has been demonstrated, indicating for the first time that L. barbarum extract inhibits human papillomavirus (HPV) type 16 cell lines. Ethanol extract of L. barbarum was used for cell viability evaluation on SCC090, CAL27, and HGnF cell lines. After 24 and 48 h, the cell cycle effect of L. barbarum extract (at 1.0, 10, and 100 µg/mL) was measured via flow cytometry. In addition, the mRNA expression on E6/E7 and p53 via RT-PCR and the expression of p16, p53, Ki-67, and Bcl-2 via immunohistochemistry were also determined. Untreated cells, 20 µM cisplatin, and a Camellia sinensis-derived extract were used as negative and positive controls, respectively. We demonstrated that the studied L. barbarum extract resulted in G0/G1 arrest and S phase accumulation in SCC090 at 1.0 and 10 μg/mL. A reduction in mRNA levels of E6/E7 oncogenes (p < 0.05) with p53 overexpression was also observed through PCR, while immunohistochemical analyses indicated p16 overexpression (p > 0.05) and a decrease in p53 overexpression. The observed effects were associated with anticancer and immunomodulatory phenolics, such as flavonols/flavan-3-ols and tyramine-conjugated hydroxycinnamic acid amides, identified in the studied extract. These findings revealed that the phenolic-rich extract of L. barbarum fruits has promising properties to be considered further for developing new therapies against oral and oropharyngeal HPV lesions.
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Affiliation(s)
- Alberto Peraza-Labrador
- Unit of Basic Oral Investigation-UIBO, School of Dentistry, Universidad El Bosque, Bogotá 110121, Colombia; (A.P.-L.); (D.M.B.)
- Cellular and Molecular Immunology Group-INMUBO, School of Dentistry, Universidad El Bosque, Bogotá 110121, Colombia
| | - Diana Marcela Buitrago
- Unit of Basic Oral Investigation-UIBO, School of Dentistry, Universidad El Bosque, Bogotá 110121, Colombia; (A.P.-L.); (D.M.B.)
| | - Ericsson Coy-Barrera
- Bioorganic Chemistry Laboratory, Department of Chemistry, Universidad Militar Nueva Granada, Cajicá 250247, Colombia;
| | - Sandra J. Perdomo-Lara
- Cellular and Molecular Immunology Group-INMUBO, School of Dentistry, Universidad El Bosque, Bogotá 110121, Colombia
- Correspondence: ; Tel.: +57-164-89000
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5
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Dynamic Spatiotemporal Expression Pattern of the Senescence-Associated Factor p16Ink4a in Development and Aging. Cells 2022; 11:cells11030541. [PMID: 35159350 PMCID: PMC8833900 DOI: 10.3390/cells11030541] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 01/27/2022] [Accepted: 02/02/2022] [Indexed: 02/01/2023] Open
Abstract
A plethora of factors have been attributed to underly aging, including oxidative stress, telomere shortening and cellular senescence. Several studies have shown a significant role of the cyclin-dependent kinase inhibitor p16ink4a in senescence and aging. However, its expression in development has been less well documented. Therefore, to further clarify a potential role of p16 in development and aging, we conducted a developmental expression study of p16, as well as of p19ARF and p21, and investigated their expression on the RNA level in brain, heart, liver, and kidney of mice at embryonic, postnatal, adult, and old ages. P16 expression was further assessed on the protein level by immunohistochemistry. Expression of p16 was highly dynamic in all organs in embryonic and postnatal stages and increased dramatically in old mice. Expression of p19 and p21 was less variable and increased to a moderate extent at old age. In addition, we observed a predominant expression of p16 mRNA and protein in liver endothelial cells versus non-endothelial cells of old mice, which suggests a functional role specifically in liver endothelium of old subjects. Thus, p16 dynamic spatiotemporal expression might implicate p16 in developmental and physiological processes in addition to its well-known function in the build-up of senescence.
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6
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Bartkowiak E, Piwowarczyk K, Bodnar M, Kosikowski P, Chou J, Woźniak A, Wierzbicka M. Expression of p16 Ink4a protein in pleomorphic adenoma and carcinoma ex pleomorphic adenoma proves diversity of tumour biology and predicts clinical course. J Clin Pathol 2021; 75:605-611. [PMID: 33941588 PMCID: PMC9411887 DOI: 10.1136/jclinpath-2021-207440] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Accepted: 04/07/2021] [Indexed: 11/28/2022]
Abstract
Aims The aim of the study is to correlate p16Ink4a expression with the clinical courses of pleomorphic adenoma (PA), its malignant transformation (CaexPA) and treatment outcomes. Methods Retrospective analysis (1998–2019) of 47 CaexPA, 148 PA and 22 normal salivary gland samples was performed. PAs were divided into two subsets: clinically ‘slow’ tumours characterised by stable size or slow growth; and ‘fast’ tumours with rapid growth rate. Results Positive p16Ink4a expression was found in 68 PA and 23 CaexPA, and borderline expression in 80 and 20, respectively. All 22 (100%) normal salivary gland samples presented with no p16Ink4a expression. Significant difference in p16Ink4a expression was observed between normal tissue, PA and CaexPA (χ2 (4)=172,19; p=0.0001). The PA clinical subgroups were also evaluated separately, revealing additional statistical relations: ‘fast’ PA and CaexPA differed significantly in p16Ink4a expression (χ2 (2)=8.06; p=0.01781) while ‘slow’ PA and CaexPA did not (χ2 (2)=3.09; p=0.2129). 3-year, 5-year and 10-year survival among p16Ink4a positive CaexPA patients was 100%, 90.56% and 60.37%, respectively, and in CaexPA patients with borderline p16Ink4a expression was 90.0%, 73.64% and 22.20%, respectively. Statistically significant difference between expression pattern and survival rate was observed (F Cox test – F (16, 24)=2.31; p=0.03075). Conclusions Our study confirms no p16Ink4a expression in normal tissue, but reveals differences in expression between ‘fast’ and ‘slow’ PA. We suggest that p16Ink4a overexpression is connected to PA proliferation and subsequent malignant transformation to CaexPA. Borderline p16Ink4a staining correlates with worse prognosis of CaexPA.
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Affiliation(s)
- Ewelina Bartkowiak
- Department of Otolaryngology and Laryngological Oncology, Poznan University of Medical Sciences, Poznan, Poland
| | - Krzysztof Piwowarczyk
- Department of Otolaryngology and Laryngological Oncology, Poznan University of Medical Sciences, Poznan, Poland
| | - Magdalena Bodnar
- Department of Otolaryngology and Laryngological Oncology, Poznan University of Medical Sciences, Poznan, Poland.,Department of Clinical Pathomorphology, Nicolaus Copernicus University in Toruń Ludwik Rydygier Collegium Medicum in Bydgoszcz, Bydgoszcz, Poland
| | - Paweł Kosikowski
- Department of Clinical Pathology, Poznan University of Medical Sciences, Poznan, Poland
| | - Jadzia Chou
- Department of Otolaryngology and Laryngological Oncology, Poznan University of Medical Sciences, Poznan, Poland
| | - Aldona Woźniak
- Department of Clinical Pathology, Poznan University of Medical Sciences, Poznan, Poland
| | - Małgorzata Wierzbicka
- Department of Otolaryngology and Laryngological Oncology, Poznan University of Medical Sciences, Poznan, Poland
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7
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Role of Cdkn2a in the Emery-Dreifuss Muscular Dystrophy Cardiac Phenotype. Biomolecules 2021; 11:biom11040538. [PMID: 33917623 PMCID: PMC8103514 DOI: 10.3390/biom11040538] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Revised: 03/23/2021] [Accepted: 03/23/2021] [Indexed: 12/21/2022] Open
Abstract
The Cdkn2a locus is one of the most studied tumor suppressor loci in the context of several cancer types. However, in the last years, its expression has also been linked to terminal differentiation and the activation of the senescence program in different cellular subtypes. Knock-out (KO) of the entire locus enhances the capability of stem cells to proliferate in some tissues and respond to severe physiological and non-physiological damages in different organs, including the heart. Emery-Dreifuss muscular dystrophy (EDMD) is characterized by severe contractures and muscle loss at the level of skeletal muscles of the elbows, ankles and neck, and by dilated cardiomyopathy. We have recently demonstrated, using the LMNA Δ8-11 murine model of Emery-Dreifuss muscular dystrophy (EDMD), that dystrophic muscle stem cells prematurely express non-lineage-specific genes early on during postnatal growth, leading to rapid exhaustion of the muscle stem cell pool. Knock-out of the Cdkn2a locus in EDMD dystrophic mice partially restores muscle stem cell properties. In the present study, we describe the cardiac phenotype of the LMNA Δ8-11 mouse model and functionally characterize the effects of KO of the Cdkn2a locus on heart functions and life expectancy.
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Pouli D, Thieu HT, Genega EM, Baecher-Lind L, House M, Bond B, Roncari DM, Evans ML, Rius-Diaz F, Munger K, Georgakoudi I. Label-free, High-Resolution Optical Metabolic Imaging of Human Cervical Precancers Reveals Potential for Intraepithelial Neoplasia Diagnosis. CELL REPORTS MEDICINE 2020; 1. [PMID: 32577625 PMCID: PMC7311071 DOI: 10.1016/j.xcrm.2020.100017] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
While metabolic changes are considered a cancer hallmark, their assessment has not been incorporated in the detection of early or precancers, when treatment is most effective. Here, we demonstrate that metabolic changes are detected in freshly excised human cervical precancerous tissues using label-free, non-destructive imaging of the entire epithelium. The images rely on two-photon excited fluorescence from two metabolic co-enzymes, NAD(P)H and FAD, and have micron-level resolution, enabling sensitive assessments of the redox ratio and mitochondrial fragmentation, which yield metrics of metabolic function and heterogeneity. Simultaneous characterization of morphological features, such as the depth-dependent variation of the nuclear:cytoplasmic ratio, is demonstrated. Multi-parametric analysis combining several metabolic metrics with morphological ones enhances significantly the diagnostic accuracy of identifying high-grade squamous intraepithelial lesions. Our results motivate the translation of such functional metabolic imaging to in vivo studies, which may enable improved identification of cervical lesions, and other precancers, at the bedside.
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Affiliation(s)
- Dimitra Pouli
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA.,Present address: Department of Pathology, Beth Israel Deaconess Medical Center and Harvard Medical School, 330 Brookline Avenue, Boston, MA 02115, USA
| | - Hong-Thao Thieu
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Elizabeth M Genega
- Department of Pathology and Laboratory Medicine, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Laura Baecher-Lind
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Michael House
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Brian Bond
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA.,Present address: Department of Obstetrics and Gynecology, University of Massachusetts School of Medicine, 55 Lake Avenue North, Worcester, MA 01655, USA
| | - Danielle M Roncari
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Megan L Evans
- Department of Obstetrics and Gynecology, Tufts University School of Medicine, Tufts Medical Center, 800 Washington Street, Boston, MA 02111, USA
| | - Francisca Rius-Diaz
- Department of Preventive Medicine and Public Health, Faculty of Medicine, University of Málaga, 32 Louis Pasteur Boulevard, 29071 Málaga, Spain
| | - Karl Munger
- Department of Developmental, Molecular, and Chemical Biology, Tufts University School of Medicine, 136 Harrison Avenue, Boston, MA 02111, USA
| | - Irene Georgakoudi
- Department of Biomedical Engineering, Tufts University, 4 Colby Street, Medford, MA 02155, USA.,Lead Contact
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9
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Kiatpakdee B, Sato K, Otsuka Y, Arashiki N, Chen Y, Tsumita T, Otsu W, Yamamoto A, Kawata R, Yamazaki J, Sugimoto Y, Takada K, Mohandas N, Inaba M. Cholesterol-binding protein TSPO2 coordinates maturation and proliferation of terminally differentiating erythroblasts. J Biol Chem 2020; 295:8048-8063. [PMID: 32358067 PMCID: PMC7278357 DOI: 10.1074/jbc.ra119.011679] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Revised: 04/20/2020] [Indexed: 02/02/2023] Open
Abstract
TSPO2 (translocator protein 2) is a transmembrane protein specifically expressed in late erythroblasts and has been postulated to mediate intracellular redistribution of cholesterol. We identified TSPO2 as the causative gene for the HK (high-K+) trait with immature red cell phenotypes in dogs and investigated the effects of the TSPO2 defects on erythropoiesis in HK dogs with the TSPO2 mutation and Tspo2 knockout (Tspo2−/−) mouse models. Bone marrow–derived erythroblasts from HK dogs showed increased binucleated and apoptotic cells at various stages of maturation and shed large nuclei with incomplete condensation when cultured in the presence of erythropoietin, indicating impaired maturation and cytokinesis. The canine TSPO2 induces cholesterol accumulation in the endoplasmic reticulum and could thereby regulate cholesterol availability by changing intracellular cholesterol distribution in erythroblasts. Tspo2−/− mice consistently showed impaired cytokinesis with increased binucleated erythroblasts, resulting in compensated anemia, and their red cell membranes had increased Na,K-ATPase, resembling the HK phenotype in dogs. Tspo2-deficient mouse embryonic stem cell–derived erythroid progenitor (MEDEP) cells exhibited similar morphological defects associated with a cell-cycle arrest at the G2/M phase, resulting in decreased cell proliferation and had a depletion in intracellular unesterified and esterified cholesterol. When the terminal maturation was induced, Tspo2−/− MEDEP cells showed delays in hemoglobinization; maturation-associated phenotypic changes in CD44, CD71, and TER119 expression; and cell-cycle progression. Taken together, these findings imply that TSPO2 is essential for coordination of maturation and proliferation of erythroblasts during normal erythropoiesis.
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Affiliation(s)
- Benjaporn Kiatpakdee
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Kota Sato
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Yayoi Otsuka
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Nobuto Arashiki
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Yuqi Chen
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Takuya Tsumita
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Wataru Otsu
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Akito Yamamoto
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Reo Kawata
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Jumpei Yamazaki
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | | | - Kensuke Takada
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
| | - Narla Mohandas
- Red Cell Physiology Laboratory, New York Blood Center, New York, New York, USA
| | - Mutsumi Inaba
- Laboratory of Molecular Medicine, Graduate School of Veterinary Medicine, Hokkaido University, Sapporo, Japan
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10
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Sudo T, Yokota T, Okuzaki D, Ueda T, Ichii M, Ishibashi T, Isono T, Habuchi Y, Oritani K, Kanakura Y. Endothelial Cell-Selective Adhesion Molecule Expression in Hematopoietic Stem/Progenitor Cells Is Essential for Erythropoiesis Recovery after Bone Marrow Injury. PLoS One 2016; 11:e0154189. [PMID: 27111450 PMCID: PMC4844162 DOI: 10.1371/journal.pone.0154189] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 04/11/2016] [Indexed: 02/01/2023] Open
Abstract
Numerous red blood cells are generated every second from proliferative progenitor cells under a homeostatic state. Increased erythropoietic activity is required after myelo-suppression as a result of chemo-radio therapies. Our previous study revealed that the endothelial cell-selective adhesion molecule (ESAM), an authentic hematopoietic stem cell marker, plays essential roles in stress-induced hematopoiesis. To determine the physiological importance of ESAM in erythroid recovery, ESAM-knockout (KO) mice were treated with the anti-cancer drug, 5-fluorouracil (5-FU). ESAM-KO mice experienced severe and prolonged anemia after 5-FU treatment compared to wild-type (WT) mice. Eight days after the 5-FU injection, compared to WT mice, ESAM-KO mice showed reduced numbers of erythroid progenitors in bone marrow (BM) and spleen, and reticulocytes in peripheral blood. Megakaryocyte-erythrocyte progenitors (MEPs) from the BM of 5-FU-treated ESAM-KO mice showed reduced burst forming unit-erythrocyte (BFU-E) capacities than those from WT mice. BM transplantation revealed that hematopoietic stem/progenitor cells from ESAM-KO donors were more sensitive to 5-FU treatment than that from WT donors in the WT host mice. However, hematopoietic cells from WT donors transplanted into ESAM-KO host mice could normally reconstitute the erythroid lineage after a BM injury. These results suggested that ESAM expression in hematopoietic cells, but not environmental cells, is critical for hematopoietic recovery. We also found that 5-FU treatment induces the up-regulation of ESAM in primitive erythroid progenitors and macrophages that do not express ESAM under homeostatic conditions. The phenotypic change seen in macrophages might be functionally involved in the interaction between erythroid progenitors and their niche components during stress-induced acute erythropoiesis. Microarray analyses of primitive erythroid progenitors from 5-FU-treated WT and ESAM-KO mice revealed that various signaling pathways, including the GATA1 system, were impaired in ESAM-KO mice. Thus, our data demonstrate that ESAM expression in hematopoietic progenitors is essential for erythroid recovery after a BM injury.
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Affiliation(s)
- Takao Sudo
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Takafumi Yokota
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
- * E-mail:
| | - Daisuke Okuzaki
- DNA Chip Development Center, Research Institute for Microbial Diseases, Osaka University, Suita, Osaka, Japan
| | - Tomoaki Ueda
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Michiko Ichii
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Tomohiko Ishibashi
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Tomomi Isono
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Yoko Habuchi
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Kenji Oritani
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
| | - Yuzuru Kanakura
- Department of Hematology and Oncology, Osaka University Graduate School of Medicine, Suita, Osaka, Japan
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11
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Hui KF, Leung YY, Yeung PL, Middeldorp JM, Chiang AKS. Combination of SAHA and bortezomib up-regulates CDKN2A and CDKN1A and induces apoptosis of Epstein-Barr virus-positive Wp-restricted Burkitt lymphoma and lymphoblastoid cell lines. Br J Haematol 2014; 167:639-50. [PMID: 25155625 DOI: 10.1111/bjh.13089] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2014] [Accepted: 07/15/2014] [Indexed: 01/22/2023]
Abstract
Epstein-Barr virus (EBV) latent proteins exert anti-apoptotic effects on EBV-transformed lymphoid cells by down-regulating BCL2L11 (BIM), CDKN2A (p16(INK4A) ) and CDKN1A (p21(WAF1) ). However, the potential therapeutic effects of targeting these anti-apoptotic mechanisms remain unexplored. Here, we tested both in vitro and in vivo effects of the combination of histone deacetylase (HDAC) and proteasome inhibitors on the apoptosis of six endemic Burkitt lymphoma (BL) lines of different latency patterns (types I and III and Wp-restricted) and three lymphoblastoid cell lines (LCLs). We found that the combination of HDAC and proteasome inhibitors (e.g. SAHA/bortezomib) synergistically induced the killing of Wp-restricted and latency III BL and LCLs but not latency I BL cells. The synergistic killing was due to apoptosis, as evidenced by the high percentage of annexin V positivity and strong cleavage of PARP1 (PARP) and CASP3 (caspase-3). Concomitantly, SAHA/bortezomib up-regulated the expression of CDKN2A and CDKN1A but did not affect the level of BCL2L11 or BHRF1 (viral homologue of BCL2). The apoptotic effects were dependent on reactive oxygen species generation. Furthermore, SAHA/bortezomib suppressed the growth of Wp-restricted BL xenografts in nude mice. This study provides the rationale to test the novel application of SAHA/bortezomib on the treatment of EBV-associated Wp-restricted BL and post-transplant lymphoproliferative disorder.
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Affiliation(s)
- Kwai Fung Hui
- Department of Paediatrics and Adolescent Medicine, Li Ka Shing Faculty of Medicine, The University of Hong Kong, Queen Mary Hospital, Pokfulam, Hong Kong, SAR, China
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12
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Dissecting the transcriptional phenotype of ribosomal protein deficiency: implications for Diamond-Blackfan Anemia. Gene 2014; 545:282-9. [PMID: 24835311 PMCID: PMC4058751 DOI: 10.1016/j.gene.2014.04.077] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2013] [Revised: 04/04/2014] [Accepted: 04/29/2014] [Indexed: 11/26/2022]
Abstract
Defects in genes encoding ribosomal proteins cause Diamond Blackfan Anemia (DBA), a red cell aplasia often associated with physical abnormalities. Other bone marrow failure syndromes have been attributed to defects in ribosomal components but the link between erythropoiesis and the ribosome remains to be fully defined. Several lines of evidence suggest that defects in ribosome synthesis lead to “ribosomal stress” with p53 activation and either cell cycle arrest or induction of apoptosis. Pathways independent of p53 have also been proposed to play a role in DBA pathogenesis. We took an unbiased approach to identify p53-independent pathways activated by defects in ribosome synthesis by analyzing global gene expression in various cellular models of DBA. Ranking-Principal Component Analysis (Ranking-PCA) was applied to the identified datasets to determine whether there are common sets of genes whose expression is altered in these different cellular models. We observed consistent changes in the expression of genes involved in cellular amino acid metabolic process, negative regulation of cell proliferation and cell redox homeostasis. These data indicate that cells respond to defects in ribosome synthesis by changing the level of expression of a limited subset of genes involved in critical cellular processes. Moreover, our data support a role for p53-independent pathways in the pathophysiology of DBA. Ribosomopathies such as DBA are caused by ribosome dysfunction that activates p53. p53-independent pathways may suggest possible treatments for DBA. Expression analysis was performed in three p53-null models of DBA. Genes involved in apoptosis and cell redox homeostasis were especially affected. DBA is due to cumulative effects of p53-dependent and independent pathways.
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13
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Pourfarzad F, von Lindern M, Azarkeivan A, Hou J, Kia SK, Esteghamat F, van Ijcken W, Philipsen S, Najmabadi H, Grosveld F. Hydroxyurea responsiveness in β-thalassemic patients is determined by the stress response adaptation of erythroid progenitors and their differentiation propensity. Haematologica 2012; 98:696-704. [PMID: 23100274 DOI: 10.3324/haematol.2012.074492] [Citation(s) in RCA: 42] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
β-thalassemia is caused by mutations in the β-globin locus resulting in loss of, or reduced, hemoglobin A (adult hemoglobin, HbA, α2β2) production. Hydroxyurea treatment increases fetal γ-globin (fetal hemoglobin, HbF, α2γ2) expression in postnatal life substituting for the missing adult β-globin and is, therefore, an attractive therapeutic approach. Patients treated with hydroxyurea fall into three categories: i) 'responders' who increase hemoglobin to therapeutic levels; (ii) 'moderate-responders' who increase hemoglobin levels but still need transfusions at longer intervals; and (iii) 'non-responders' who do not reach adequate hemoglobin levels and remain transfusion-dependent. The mechanisms underlying these differential responses remain largely unclear. We generated RNA expression profiles from erythroblast progenitors of 8 responder and 8 non-responder β-thalassemia patients. These profiles revealed that hydroxyurea treatment induced differential expression of many genes in cells from non-responders while it had little impact on cells from responders. Part of the gene program up-regulated by hydroxyurea in non-responders was already highly expressed in responders before hydroxyurea treatment. Baseline HbF expression was low in non-responders, and hydroxyurea treatment induced significant cell death. We conclude that cells from responders have adapted well to constitutive stress conditions and display a propensity to proceed to the erythroid differentiation program.
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Nuclear factor-kappaB as a switch in regulation of resveratrol-mediated apoptosis and erythrocytic differentiation in human leukaemia cells. Food Chem 2012. [DOI: 10.1016/j.foodchem.2011.12.062] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
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15
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Perfluorooctanoic acid induces gene promoter hypermethylation of glutathione-S-transferase Pi in human liver L02 cells. Toxicology 2012; 296:48-55. [PMID: 22425687 DOI: 10.1016/j.tox.2012.03.003] [Citation(s) in RCA: 48] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2012] [Revised: 03/02/2012] [Accepted: 03/07/2012] [Indexed: 12/31/2022]
Abstract
Perfluorooctanoic acid (PFOA) is one of the most commonly used perfluorinated compounds. Being a persistent environmental pollutant, it can accumulate in human tissues via various exposure routes. PFOA may interfere in a toxic fashion on the immune system, liver, development, and endocrine systems. In utero human exposure had been associated with cord serum global DNA hypomethylation. In light of this, we investigated possible PFOA-induced DNA methylation alterations in L02 cells in order to shed light into its epigenetic-mediated mechanisms of toxicity in human liver. L02 cells were exposed to 5, 10, 25, 50 or 100 mg/L PFOA for 72h. Global DNA methylation levels were determined by LC/ESI-MS, glutathione-S-transferase Pi (GSTP) gene promoter DNA methylation was investigated by methylation-specific polymerase chain reaction (PCR) with bisulfite sequencing, and consequent mRNA expression levels were measured with quantitative real-time reverse transcriptase PCR. A dose-related increase of GSTP promoter methylation at the transcription factor specificity protein 1 (SP1) binding site was observed. However, PFOA did not significantly influence global DNA methylation; nor did it markedly alter the promoter gene methylation of p16 (cyclin-dependent kinase inhibitor 2A), ERα (estrogen receptor α) or PRB (progesterone receptor B). In addition, PFOA significantly elevated mRNA transcript levels of DNMT3A (which mediates de novo DNA methylation), Acox (lipid metabolism) and p16 (cell apoptosis). Considering the role of GSTP in detoxification, aberrant methylation may be pivotal in PFOA-mediated toxicity response via the inhibition of SP1 binding to GSTP promoter.
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16
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Romagosa C, Simonetti S, López-Vicente L, Mazo A, Lleonart ME, Castellvi J, Ramon y Cajal S. p16(Ink4a) overexpression in cancer: a tumor suppressor gene associated with senescence and high-grade tumors. Oncogene 2011; 30:2087-97. [PMID: 21297668 DOI: 10.1038/onc.2010.614] [Citation(s) in RCA: 319] [Impact Index Per Article: 24.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
p16(Ink4a) is a protein involved in regulation of the cell cycle. Currently, p16(Ink4a) is considered a tumor suppressor protein because of its physiological role and downregulated expression in a large number of tumors. Intriguingly, overexpression of p16(Ink4a) has also been described in several tumors. This review attempts to elucidate when and why p16(Ink4a) overexpression occurs, and to suggest possible implications of p16(Ink4a) in the diagnosis, prognosis and treatment of cancer.
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Affiliation(s)
- C Romagosa
- Pathology Department, Fundació Institut de Recerca, Hospital Universitari Vall d'Hebron, Universitat Autònoma de Barcelona, Barcelona, Spain
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Pradet-Balade B, Leberbauer C, Schweifer N, Boulmé F. Massive translational repression of gene expression during mouse erythroid differentiation. BIOCHIMICA ET BIOPHYSICA ACTA-GENE REGULATORY MECHANISMS 2010; 1799:630-41. [PMID: 20804875 DOI: 10.1016/j.bbagrm.2010.08.006] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/19/2010] [Revised: 08/06/2010] [Accepted: 08/18/2010] [Indexed: 12/15/2022]
Abstract
We took advantage of a mouse erythroid differentiation system to determine the relative contribution of transcriptional and translational control during this process. Comparison of expression data obtained with total cytoplasmic mRNAs or polysome-bound mRNAs (actively translated mRNAs) on Affymetrix high-density oligonucleotide microarrays revealed different characteristics of the two regulatory mechanisms. Indeed, mRNA expression from a vast majority of genes was affected, albeit most changes were relatively small and occurred at a low pace. Translational control, however, affected a smaller fraction of genes but was effective at earlier time-points. This analysis unravels six clusters of genes showing no significant variation in mRNA expression levels whereas they are submitted to translational regulation. Their involvement in terminal mouse erythropoiesis may prove to be highly relevant. Furthermore, the data from specific and functional categories of genes emphasize that translational control, not only reinforces the transcriptional effect, but allows the cell to increase the complexity in gene expression regulation patterns.
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Affiliation(s)
- Bérengère Pradet-Balade
- Department of Immunology and Oncology, Centro Nacional de Biotecnologia CNB-CSIC, Campus de Cantoblanco, Madrid, Spain
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18
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Depletion of L3MBTL1 promotes the erythroid differentiation of human hematopoietic progenitor cells: possible role in 20q- polycythemia vera. Blood 2010; 116:2812-21. [PMID: 20585043 DOI: 10.1182/blood-2010-02-270611] [Citation(s) in RCA: 44] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
L3MBTL1, the human homolog of the Drosophila L(3)MBT polycomb group tumor suppressor gene, is located on chromosome 20q12, within the common deleted region identified in patients with 20q deletion-associated polycythemia vera, myelodysplastic syndrome, and acute myeloid leukemia. L3MBTL1 is expressed within hematopoietic CD34(+) cells; thus, it may contribute to the pathogenesis of these disorders. To define its role in hematopoiesis, we knocked down L3MBTL1 expression in primary hematopoietic stem/progenitor (ie, CD34(+)) cells isolated from human cord blood (using short hairpin RNAs) and observed an enhanced commitment to and acceleration of erythroid differentiation. Consistent with this effect, overexpression of L3MBTL1 in primary hematopoietic CD34(+) cells as well as in 20q- cell lines restricted erythroid differentiation. Furthermore, L3MBTL1 levels decrease during hemin-induced erythroid differentiation or erythropoietin exposure, suggesting a specific role for L3MBTL1 down-regulation in enforcing cell fate decisions toward the erythroid lineage. Indeed, L3MBTL1 knockdown enhanced the sensitivity of hematopoietic stem/progenitor cells to erythropoietin (Epo), with increased Epo-induced phosphorylation of STAT5, AKT, and MAPK as well as detectable phosphorylation in the absence of Epo. Our data suggest that haploinsufficiency of L3MBTL1 contributes to some (20q-) myeloproliferative neoplasms, especially polycythemia vera, by promoting erythroid differentiation.
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Churdchomjan W, Kheolamai P, Manochantr S, Tapanadechopone P, Tantrawatpan C, U-pratya Y, Issaragrisil S. Comparison of endothelial progenitor cell function in type 2 diabetes with good and poor glycemic control. BMC Endocr Disord 2010; 10:5. [PMID: 20374643 PMCID: PMC2858721 DOI: 10.1186/1472-6823-10-5] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/28/2009] [Accepted: 04/07/2010] [Indexed: 01/31/2023] Open
Abstract
BACKGROUND Endothelial progenitor cells (EPCs) play an important role in vascular repair and a decrease in the number of EPCs is observed in type 2 diabetes. However, there is no report on the change of EPCs after glycemic control. This study therefore aimed to investigate the EPC number and function in patients with good and poor glycemic control. METHODS The number of EPCs was studied using flow cytometry by co-expression of CD34 and VEGFR2. The EPCs were cultured and characterized by the expression of UEA-I, CD34, VEGFR2, vWF and Dil-Ac-LDL engulfment, as well as the ability to form capillary-like structures. An in vitro study on the effect of hyperglycemia on the proliferation and viability of the cultured EPCs was also performed. RESULTS The number of EPCs in type 2 diabetes was significantly decreased compared with healthy controls and there was an inverse correlation between the EPC numbers and plasma glucose, as well as HbA1C. The number and function of EPCs in patients with good glycemic control were recovered compared with those with poor glycemic control. When glucose was supplemented in the culture in vitro, there was a negative effect on the proliferation and viability of EPCs, in a dose-dependent manner, whereas the enhancement of apoptosis was observed. CONCLUSION There was EPC dysfunction in type 2 diabetes which might be improved by strict glycemic control. However, the circulating EPC number and proliferative function in patients with good glycemic control did not reach the level in healthy controls.
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Affiliation(s)
- Worachat Churdchomjan
- Division of Cell Biology, Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani 12120, Thailand
| | - Pakpoom Kheolamai
- Division of Cell Biology, Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani 12120, Thailand
| | - Sirikul Manochantr
- Division of Cell Biology, Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani 12120, Thailand
| | - Pirath Tapanadechopone
- Division of Cell Biology, Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani 12120, Thailand
| | - Chairat Tantrawatpan
- Division of Cell Biology, Department of Preclinical Sciences, Faculty of Medicine, Thammasat University, Pathumthani 12120, Thailand
| | - Yaowalak U-pratya
- Division of Hematology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
| | - Surapol Issaragrisil
- Division of Hematology, Department of Medicine, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok 10700, Thailand
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20
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Finnberg N, Wambi C, Ware JH, Kennedy AR, El-Deiry WS. Gamma-radiation (GR) triggers a unique gene expression profile associated with cell death compared to proton radiation (PR) in mice in vivo. Cancer Biol Ther 2008; 7:2023-33. [PMID: 19106632 DOI: 10.4161/cbt.7.12.7417] [Citation(s) in RCA: 47] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
Proton radiation (PR) therapy offers a number of potential advantages over conventional (photon) gamma-radiation (GR) therapy for cancer, due to a more localized delivery of the radiation dose. However, the pathophysiological effects following PR-exposure are less well characterized than those of GR-exposure and the molecular changes associated with the acute apoptotic effects in mice in vivo following PR have not been elucidated. Previous studies have estimated the RBE of protons for various in vivo and in vitro endpoints at between 1.1 and 1.3. We assumed an RBE of 1.1 for the endpoints to be evaluated in these studies. Based on this assumption, ICR mice were treated with whole-body doses of GR (1.1 and 7.0 Gy) and PR (1.0 and 6.4 Gy) that were expected to represent RBE-weighted doses. The bone marrow, thymus, spleen and GI-tract were isolated and processed for histology and immunohistochemistry. The apoptotic responses varied greatly between GR and PR in a tissue- and dose-dependent manner. Surprisingly,cell death in the splenic white pulp was consistently lower in PR-treated animals compared to animals treated with GR. This was in spite of an increased presence of damaged DNA following PR as determined by staining for gammaH2AX and phospho-ATM. Interestingly, both PR and GR triggered nuclear accumulation of p53 and no significant differences were found in the majority of the known pro-apoptotic p53-target genes in the spleens of treated mice. However, GR uniquely triggered a pro-apoptotic expression profile including expression of the pro-apoptotic, p53- and interferon stimulated target gene Bcl-G. In contrast to PR, GR may, in a cell type specific manner, trigger a more diverse non-random stress-response that mediates apoptosis partially independent of the extent of DNA damage.
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Affiliation(s)
- Niklas Finnberg
- Laboratory of Molecular Oncology and Cell Cycle Regulation, The Institute for Translational Medicine and Therapeutics, The Abramson Comprehensive Cancer Center, University of Pennsylvania School of Medicine, Philadelphia, Pennsylvania, USA
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21
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Expression of anion exchanger 1 sequestrates p16 in the cytoplasm in gastric and colonic adenocarcinoma. Neoplasia 2007; 9:812-9. [PMID: 17971901 DOI: 10.1593/neo.07403] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2007] [Revised: 08/14/2007] [Accepted: 08/14/2007] [Indexed: 01/29/2023] Open
Abstract
p16(INK4A) (p16) binds to cyclin-dependent kinase 4/6 and negatively regulates cell growth. Recent studies have led to an understanding of additional biologic functions for p16; however, the detailed mechanisms involved are still elusive. In this article, we show an unexpected expression of anion exchanger 1 (AE1) in the cytoplasm in poorly and moderately differentiated gastric and colonic adenocarcinoma cells and in its interaction with p16, thereby sequestrating the protein in the cytoplasm. Genetic alterations of p16 and AE1 were not detectable. Forced expression of AE1 in these cells sequestrated more p16 in the cytoplasm, whereas small interfering RNA-mediated silencing of AE1 in the cells induced the release of p16 from the cytoplasm to the nucleus, leading to cell death and growth inhibition of tumor cells. By analyzing tissue samples obtained from patients with gastric and colonic cancers, we found that 83.33% of gastric cancers and 56.52% of colonic cancers coexpressed AE1 and p16 in the cytoplasm. We conclude that AE1 plays a crucial role in the pathogenesis of gastric and colonic adenocarcinoma and that p16 dysfunction is a novel pathway of carcinogenesis.
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22
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Wang X, Pan L, Feng Y, Wang Y, Han Q, Han L, Han S, Guo J, Huang B, Lu J. P300 plays a role in p16(INK4a) expression and cell cycle arrest. Oncogene 2007; 27:1894-904. [PMID: 17906698 DOI: 10.1038/sj.onc.1210821] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
As a cyclin-dependent kinase inhibitor, p16(INK4a) plays a key role in cell cycle progression and cellular differentiation, and its expression is frequently altered in human cancers through epigenetically mediated transcriptional silencing. In this report, we demonstrate that p300 was able to induce cell cycle arrest, and this process was reversed by p16(INK4a) silencing by RNA interference in HeLa cells. We also show that p300 was involved in activation of p16(INK4a) expression in 293T cells. Specifically, p300 cooperated with Sp1 to stimulate both p16(INK4a) promoter activity and mRNA expression. Co-immunoprecipitation and mammalian two-hybrid assays revealed that p300 and Sp1 formed a complex through interaction between the Q domain of p300 and the N-terminal domain of Sp1. The chromatin immunoprecipitation assays verified that p300 was recruited to p16(INK4a) promoter, and the histone acetyltransferase domain of p300 participated in p16(INK4a) activation through inducing hyperacetylation of histone H4 at p16(INK4a) gene. These data suggest that p300 plays a critical role in transcriptional regulation of p16(INK4a) and in cell cycle arrest.
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Affiliation(s)
- X Wang
- Institute of Genetics and Cytology, Northeast Normal University, Changchun, China
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23
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Xie L, Qin WX, Li JJ, He XH, Shu HQ, Yao GF, Wan DF, Gu JR. cDNA expression array analysis of gene expression in human hepatocarcinoma Hep3B cells induced by BNIPL-1. Acta Biochim Biophys Sin (Shanghai) 2005; 37:618-24. [PMID: 16143817 DOI: 10.1111/j.1745-7270.2005.00086.x] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
Bcl-2/adenovirus E1B 19 kDa interacting protein 2 like-1 (BNIPL-1) is a novel human protein identified in our laboratory, which can interact with Bcl-2 and Cdc42GAP and induce apoptosis via the BNIP-2 and Cdc42GAP homology (BCH) domain. In the present study, we established the Hep3B-Tet-on stable cell line in which expression of BNIPL-1 can be induced by doxycycline. The cell proliferation activity assay showed that the overexpression of BNIPL-1 suppresses Hep3B cell growth in vitro. The differential expression profiles of 588 known genes from BNIPL-1-transfected Hep3B-Tet-on and vector control cells were determined using the Atlas human cDNA expression array. Fifteen genes were differentially expressed between these two cell lines, among which seven genes were up-regulated and eight genes were down-regulated by BINPL-1. Furthermore, the differential expression result was confirmed by semiquantitative RT-PCR. Among these differentially expressed genes, p16INK4, IL-12, TRAIL and the lymphotoxin beta gene involved in growth suppression or cell apoptosis were up-regulated, and PTEN involved in cell proliferation was down-regulated by BNIPL-1. These results suggest that BNIPL-1 might inhibit cell growth though cell cycle arrest and/or apoptotic cell death pathway(s).
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Affiliation(s)
- Li Xie
- Shanghai Medical College, Fudan University, Shanghai 200032, China
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24
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Sung YH, Park J, Choi B, Kim J, Cheong C, Choi YS, Yang EY, Lee M, Han JS, Park SC, Han TH, Kim TJ, Song J, Rhee K, Lee HW. Hematopoietic malignancies associated with increased Stat5 and Bcl-xL expressions in Ink4a/Arf-deficient mice. Mech Ageing Dev 2005; 126:732-9. [PMID: 15888328 DOI: 10.1016/j.mad.2005.01.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
The INK4a/ARF locus, which encodes the two distinct proteins p16(INK4a) and p14(ARF), is frequently altered in various hematological malignancies as well as in other types of cancers in humans. In this study, we surveyed tumors that had spontaneously developed in Ink4a/Arf-deficient mice with an inbred FVB/NJ genetic background. We found that an Ink4a/Arf-deficiency exerted more severe effects on the induction of hematopoietic malignancies in mice with an inbred FVB/NJ genetic background than in mice with a mixed genetic background. We also provided the evidence that this prevalence of hematopoietic malignancies in Ink4a/Arf-deficient mice is associated with the upregulated expressions of Stat5 and its transcriptional target, Bcl-x(L), both of which are involved in the regulation of hematopoiesis. These results suggest a possible implication of the Ink4a/Arf locus in the control of hematopoietic pathways by negatively regulating the Stat5-signalling pathways.
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Affiliation(s)
- Young Hoon Sung
- Department of Molecular Cell Biology, Samsung Biomedical Research Institute, Sungkyunkwan University School of Medicine, Suwon, Republic of Korea
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Fu GH, Wang Y, Xi YH, Shen WW, Pan XY, Shen WZ, Jiang XS, Chen GQ. Direct interaction and cooperative role of tumor suppressor p16 with band 3 (AE1). FEBS Lett 2005; 579:2105-10. [PMID: 15811326 DOI: 10.1016/j.febslet.2005.02.063] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2004] [Revised: 02/07/2005] [Accepted: 02/17/2005] [Indexed: 10/25/2022]
Abstract
By using the C-terminal 112-residue of band 3 to screen the K562 cDNA library, we find that the p16 interacts with band 3, which was confirmed both in yeast and in mammalian cells. Functional experiments show that p16 facilitates the movement of band 3 to plasma membrane with increased anion transport activity in 293t cells. Moreover, expression of endogenous p16 in 293t cells was increased at 24 and 36 h after transfection with band 3. Our findings provide a novel regulation pathway for both band 3 and p16.
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Affiliation(s)
- Guo-Hui Fu
- Department of Pathophysiology, Shanghai Institute of Hematology, Rui-Jin Hospital, Shanghai Second Medical University (SSMU), Shanghai 200025, PR China.
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Muñoz-Alonso MJ, Acosta JC, Richard C, Delgado MD, Sedivy J, León J. p21Cip1 and p27Kip1 Induce Distinct Cell Cycle Effects and Differentiation Programs in Myeloid Leukemia Cells. J Biol Chem 2005; 280:18120-9. [PMID: 15746092 DOI: 10.1074/jbc.m500758200] [Citation(s) in RCA: 77] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The cyclin-dependent kinase (Cdk) inhibitors p21(Cip1) and p27(Kip1) have been proposed to exert redundant functions in cell cycle progression and differentiation programs, although nonoverlapping functions have also been described. To gain further insights into the relevant mechanisms and to detect possible functional differences between both proteins, we conditionally expressed p21(Cip1) and p27(Kip1) in K562, a multipotent human leukemia cell line. Temporal ectopic expression of either p21(Cip1) or p27(Kip1) arrested proliferation, inhibited Cdk2 and Cdk4 activities, and suppressed retinoblastoma phosphorylation. However, whereas p21(Cip1) arrested cells in both G(1) and G(2) cell cycle phases, p27(Kip1) blocked the G(1)/S-phase transition. Furthermore, although both p21(Cip1) and p27(Kip1) associated with Cdk6, only p27(Kip1) significantly inhibited its activity. Most importantly, each protein promoted differentiation along a distinct pathway; p21(Cip1) triggered megakaryocytic maturation, whereas p27(Kip1) resulted in the expression of erythroid markers. Consistently, p21(Cip1) and p27(Kip1) were rapid and transiently up-regulated when K562 cells are differentiated into megakaryocytic and erythroid lineages, respectively. These findings demonstrate distinct functions of p21(Cip1) and p27(Kip1) in cell cycle regulation and differentiation and indicate that these two highly related proteins possess unique biological activities and are not functionally interchangeable.
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Affiliation(s)
- María J Muñoz-Alonso
- Grupo de Biología Molecular del Cáncer, Departamento de Biología Molecular y Unidad de Biomedicina-Consejo Superior de Investigaciones Científicas, Universidad de Cantabria, 39011 Santander, Spain
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Kränkel N, Adams V, Linke A, Gielen S, Erbs S, Lenk K, Schuler G, Hambrecht R. Hyperglycemia reduces survival and impairs function of circulating blood-derived progenitor cells. Arterioscler Thromb Vasc Biol 2005; 25:698-703. [PMID: 15662022 DOI: 10.1161/01.atv.0000156401.04325.8f] [Citation(s) in RCA: 166] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
OBJECTIVE Function and availability of circulating progenitor cells (CPC) have been shown to be impaired in patients with diabetes mellitus (DM). Therefore, the aim of the present study was to analyze possible mechanisms leading to the reduction of CPC amount and function. METHODS AND RESULTS Peripheral blood mononuclear cells (MNCs) of healthy donors (n=15) were cultivated under hyperglycemia (HG) conditions (12 mmol/L D-Glucose) or in osmotic control medium (Con) (5 mmol/L D-Glucose plus 7 mmol/L L-Glucose) for 7 days. CPC amount was determined by uptake of acetylated low-density lipoprotein and lectin binding. On the functional level, cell cycle status, nitric oxide (NO) production, and migrational and integrative capacity of CPCs were assessed. HG conditions caused a significant decrease in CPC amount derived from healthy MNCs. Furthermore, HG conditions led to a functional impairment, reflected in a decreased NO production and matrix metalloproteinase (MMP)-9 activity, as well as an impairment of the migrational and integrative capacities. CONCLUSIONS HG, a main feature of DM, affects important functional characteristics of CPCs. These results may provide further insight into the pathomechanism of endothelial dysfunction in HG.
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Affiliation(s)
- Nicolle Kränkel
- Department of Internal Medicine/Cardiology, Heart Center Leipzig, University of Leipzig, Germany
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28
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Zhang H, Rosdahl I. Expression profiles of Id1 and p16 proteins in all-trans-retinoic acid-induced apoptosis and cell cycle re-distribution in melanoma. Cancer Lett 2005; 217:33-41. [PMID: 15596294 DOI: 10.1016/j.canlet.2004.07.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2004] [Revised: 07/08/2004] [Accepted: 07/09/2004] [Indexed: 10/26/2022]
Abstract
All-trans-retinoic acid (atRA) exerts its effects via apoptosis and cell cycle re-distribution. However, the mechanisms behind the effects have not been fully understood. In this study, we used a model system of matched primary and metastatic melanoma cells to investigate whether expression of Id1 and p16 proteins were involved in atRA-induced apoptosis and cell cycle re-distribution. Melanoma cells were exposed to 0.1 or 10 microM atRA for 1-96 h. Apoptosis and cell cycle were measured by flow cytometry. Expression of Id1 and p16 proteins was examined by Western blotting and immunocytochemistry. After exposure to atRA we found a marked increase in apoptosis and cell cycle re-distribution in both primary and metastatic melanoma cells. Expression level of Id1 protein was decreased and the p16 was increased in a dose- and time-dependent (P<0.05) manner after treatment with atRA. Alterations of these proteins were more pronounced in the primary melanoma cells than the matched metastases (P<0.05). These data suggested that the alterations of Id1 and/or p16 proteins were involved in atRA-induced apoptosis and cell cycle re-distribution in melanoma. These expression profiles of Id1 and p16 proteins may provide molecular evidence for better chemotherapy primarily for early stages of melanoma.
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Affiliation(s)
- Hong Zhang
- Division of Dermatology, Clinical Research Centre, Department of Biomedicine and Surgery, Linköping University, SE-581 85 Linköping, Sweden.
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Asari S, Sakamoto A, Okada S, Ohkubo Y, Arima M, Hatano M, Kuroda Y, Tokuhisa T. Abnormal erythroid differentiation in neonatal bcl-6-deficient mice. Exp Hematol 2005; 33:26-34. [PMID: 15661395 DOI: 10.1016/j.exphem.2004.10.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2004] [Revised: 10/01/2004] [Accepted: 10/04/2004] [Indexed: 10/25/2022]
Abstract
OBJECTIVE The bcl-6 proto-oncogene is ubiquitously expressed in various tissues. Since we found out the smaller number of TER119(+) cells in the spleen of neonatal bcl-6-deficient (bcl-6(-/-)) mice compared with that of control (bcl-6(+/+)) littermates, we studied functions of bcl-6 in differentiation of erythroid lineage cells. MATERIALS AND METHODS Erythroblasts in the definitive erythropoiesis were separated into four subsets using anti-TER119 and anti-CD71 mAbs. The cell number and property of these four subsets in spleens of neonatal bcl-6(+/+) and bcl-6(-/-) mice were examined using a flow cytometry. RESULTS bcl-6 mRNA expression was detected in the TER119(high)CD71(high) subset, which is morphologically equivalent to basophilic erythroblasts, by reverse-transcribed polymerase chain reaction. High percentages of cells in the TER119(low)CD71(high) and TER119(high)CD71(high) subsets were in the cell cycle. The cell number of the TER119(high)CD71(high) subset in the spleen and the percentage of reticulocytes in the peripheral blood of neonatal bcl-6(-/-) mice were significantly lower than those of neonatal bcl-6(+/+) mice. However, the percentage of apoptotic cells and that of cells in the cell cycle in the TER119(high)CD71(high) subset of bcl-6(-/-) mice were similar to those of bcl-6(+/+) mice. CONCLUSION bcl-6 detected in the TER119(high)CD71(high) subset of erythroblasts in the spleen of neonatal mice may be required to retain the erythroblasts in the cell proliferation stage.
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Affiliation(s)
- Sadaki Asari
- Department of Developmental Genetics (H2), Graduate School of Medicine, Chiba University, Chiba, Japan
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Nilsson K, Svensson S, Landberg G. Retinoblastoma protein function and p16INK4a expression in actinic keratosis, squamous cell carcinoma in situ and invasive squamous cell carcinoma of the skin and links between p16INK4a expression and infiltrative behavior. Mod Pathol 2004; 17:1464-74. [PMID: 15257310 DOI: 10.1038/modpathol.3800220] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
p16INK4a is involved in many important regulatory events in the cell and the expression and function is closely associated with the retinoblastoma protein (Rb). Earlier, we have in colorectal cancer and in basal cell carcinoma showed that p16INK4a is upregulated at the invasive front causing cell cycle arrest in infiltrative tumor cells via a functional Rb. This role for p16INK4a as a regulator of proliferation when tumor cells infiltrate might besides a general cyclin-dependent kinase (cdk) inhibitory effect explain why p16INK4a is deregulated in many tumor forms. The expression pattern of p16INK4a in relation to Rb-function in squamous cancer and precancerous forms of the skin has not been fully detailed. We therefore characterized the expression of p16INK4a, Rb-phosphorylation and proliferation in actinic keratosis, squamous cell carcinoma in situ and invasive squamous cell carcinoma with special reference to infiltrative behavior. The expression of p16INK4a varied between the lesions, with weak and cytoplasmic p16INK4a expression and functional Rb in actinic keratosis. Strong nuclear and cytoplasmic p16INK4a expression was observed in all carcinomas in situ in parallel with lack of Rb-phosphorylation but high proliferation indicating a nonfunctional Rb. Invasive squamous carcinoma showed a mixed p16INK4a expression pattern where some tumors had strong cytoplasmic p16INK4a expression, large fraction of Rb-phosphorylated cells and high proliferation. Interestingly, despite this disability of p16INK4a to inhibit proliferation there was an upregulation of cytoplasmic p16INK4a in infiltrative cells compared to tumor cells towards the tumor center. A similar scenario but strong and combined nuclear and cytoplasmic p16INK4a expression in infiltrative cells, was observed in other invasive squamous cancers. This suggests that the p16INK4a upregulation in infiltrative cells is governed independently of the subcellular localization or of the potential to affect proliferation via Rb, and suggests a potentially proliferation independent function for p16INK4a in infiltrative behavior.
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Affiliation(s)
- Kristina Nilsson
- Department of Laboratory Medicine, Division of Pathology, Lund University, Malmö University Hospital, Malmö, Sweden
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