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van Eijck CWF, Sabroso-Lasa S, Strijk GJ, Mustafa DAM, Fellah A, Koerkamp BG, Malats N, van Eijck CHJ. A liquid biomarker signature of inflammatory proteins accurately predicts early pancreatic cancer progression during FOLFIRINOX chemotherapy. Neoplasia 2024; 49:100975. [PMID: 38335839 PMCID: PMC10873733 DOI: 10.1016/j.neo.2024.100975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2024] [Accepted: 01/31/2024] [Indexed: 02/12/2024]
Abstract
BACKGROUND Pancreatic ductal adenocarcinoma (PDAC) is often treated with FOLFIRINOX, a chemotherapy associated with high toxicity rates and variable efficacy. Therefore, it is crucial to identify patients at risk of early progression during treatment. This study aims to explore the potential of a multi-omics biomarker for predicting early PDAC progression by employing an in-depth mathematical modeling approach. METHODS Blood samples were collected from 58 PDAC patients undergoing FOLFIRINOX before and after the first cycle. These samples underwent gene (GEP) and inflammatory protein expression profiling (IPEP). We explored the predictive potential of exclusively IPEP through Stepwise (Backward) Multivariate Logistic Regression modeling. Additionally, we integrated GEP and IPEP using Bayesian Kernel Regression modeling, aiming to enhance predictive performance. Ultimately, the FOLFIRINOX IPEP (FFX-IPEP) signature was developed. RESULTS Our findings revealed that proteins exhibited superior predictive accuracy than genes. Consequently, the FFX-IPEP signature consisted of six proteins: AMN, BANK1, IL1RL2, ITGB6, MYO9B, and PRSS8. The signature effectively identified patients transitioning from disease control to progression early during FOLFIRINOX, achieving remarkable predictive accuracy with an AUC of 0.89 in an independent test set. Importantly, the FFX-IPEP signature outperformed the conventional CA19-9 tumor marker. CONCLUSIONS Our six-protein FFX-IPEP signature holds solid potential as a liquid biomarker for the early prediction of PDAC progression during toxic FOLFIRINOX chemotherapy. Further validation in an external cohort is crucial to confirm the utility of the FFX-IPEP signature. Future studies should expand to predict progression under different chemotherapies to enhance the guidance of personalized treatment selection in PDAC.
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Affiliation(s)
- Casper W F van Eijck
- Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam, The Netherlands; Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center, Madrid, Spain.
| | - Sergio Sabroso-Lasa
- Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center, Madrid, Spain; Centro de Investigación Biomédica en Red-Cáncer (CIBERONC), Madrid, Spain
| | - Gaby J Strijk
- Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Dana A M Mustafa
- Department of Clinical Bioinformatics, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Amine Fellah
- Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Bas Groot Koerkamp
- Department of Surgery, Erasmus University Medical Center, Rotterdam, The Netherlands
| | - Núria Malats
- Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center, Madrid, Spain; Centro de Investigación Biomédica en Red-Cáncer (CIBERONC), Madrid, Spain
| | - Casper H J van Eijck
- Erasmus MC Cancer Institute, Erasmus University Medical Center, Rotterdam, The Netherlands; Genetic and Molecular Epidemiology Group, Spanish National Cancer Research Center, Madrid, Spain.
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2
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Tzani A, Haemmig S, Cheng HS, Perez-Cremades D, Augusto Heuschkel M, Jamaiyar A, Singh S, Aikawa M, Yu P, Wang T, Ye S, Feinberg MW, Plutzky J. FAM222A, Part of the BET-Regulated Basal Endothelial Transcriptome, Is a Novel Determinant of Endothelial Biology and Angiogenesis-Brief Report. Arterioscler Thromb Vasc Biol 2024; 44:143-155. [PMID: 37942611 PMCID: PMC10840377 DOI: 10.1161/atvbaha.123.319909] [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: 07/22/2023] [Accepted: 10/17/2023] [Indexed: 11/10/2023]
Abstract
BACKGROUND BETs (bromodomain and extraterminal domain-containing epigenetic reader proteins), including BRD4 (bromodomain-containing protein 4), orchestrate transcriptional programs induced by pathogenic stimuli, as intensively studied in cardiovascular disease and elsewhere. In endothelial cells (ECs), BRD4 directs induced proinflammatory, proatherosclerotic transcriptional responses; BET inhibitors, like JQ1, repress these effects and decrease atherosclerosis. While BET effects in pathogenic conditions have prompted therapeutic BET inhibitor development, BET action under basal conditions, including ECs, has remained understudied. To understand BET action in basal endothelial transcriptional programs, we first analyzed EC RNA-Seq data in the absence versus presence of JQ1 before using BET regulation to identify novel determinants of EC biology and function. METHODS RNA-Seq datasets of human umbilical vein ECs without and with JQ1 treatment were analyzed. After identifying C12orf34, also known as FAM222A (family with sequence similarity 222 member A), as a previously unreported, basally expressed, potently JQ1-induced EC gene, FAM222A was studied in endothelial and angiogenic responses in vitro using small-interference RNA silencing and lentiviral overexpression, in vitro, ex vivo and in vivo, including aortic sprouting, matrigel plug assays, and murine neonatal oxygen-induced retinopathy. RESULTS Resting EC RNA-Seq data indicate BETs direct transcriptional programs underlying core endothelial properties including migration, proliferation, and angiogenesis. BET inhibition in resting ECs also significantly induced a subset of mRNAs, including FAM222A-a unique BRD4-regulated gene with no reported EC role. Silencing endothelial FAM222A significantly decreased cellular proliferation, migration, network formation, aorta sprouting, and Matrigel plug vascularization through coordinated modulation of VEGF (vascular endothelial growth factor) and NOTCH mediator expression in vitro, ex vivo, in vivo; lentiviral FAM222A overexpression had opposite effects. In vivo, siFAM222A significantly repressed retinal revascularization in neonatal murine oxygen-induced retinopathy through similar angiogenic signaling modulation. CONCLUSIONS BET control over the basal endothelial transcriptome includes FAM222A, a novel, BRD4-regulated, key determinant of endothelial biology and angiogenesis.
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Affiliation(s)
- Aspasia Tzani
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Stefan Haemmig
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Henry S. Cheng
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Daniel Perez-Cremades
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Marina Augusto Heuschkel
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Anurag Jamaiyar
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Sasha Singh
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Masanori Aikawa
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Paul Yu
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Tianxi Wang
- Department of Ophthalmology, Boston Children’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Sun Ye
- Department of Ophthalmology, Boston Children’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Mark W. Feinberg
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
| | - Jorge Plutzky
- Division of Cardiovascular Medicine, Brigham and Women’s Hospital, Boston, MA 02115
- Harvard Medical School, Boston, MA 02115
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3
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Park S, Oh S, Kim N, Kim EK. HMBA ameliorates obesity by MYH9- and ACTG1-dependent regulation of hypothalamic neuropeptides. EMBO Mol Med 2023; 15:e18024. [PMID: 37984341 DOI: 10.15252/emmm.202318024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 10/19/2023] [Accepted: 10/27/2023] [Indexed: 11/22/2023] Open
Abstract
The global epidemic of obesity remains a daunting problem. Here, we report hexamethylene bisacetamide (HMBA) as a potent anti-obesity compound. Peripheral and central administration of HMBA to diet-induced obese mice regulated the expression of hypothalamic neuropeptides critical for energy balance, leading to beneficial metabolic effects such as anorexia and weight loss. We found that HMBA bound to MYH9 and ACTG1, which were required for the anti-obesity effects of HMBA in both NPY-expressing and POMC-expressing neurons. The binding of HMBA to MYH9 and ACTG1 elevated the expression of HEXIM1 and enhanced its interaction with MDM2, resulting in the dissociation of the HEXIM1-p53 complex in hypothalamic cells. Subsequently, the free HEXIM1 and p53 translocated to the nucleus, where they downregulated the transcription of orexigenic NPY, but p53 and acetylated histone 3 upregulated that of anorexigenic POMC. Our study points to a previously unappreciated efficacy of HMBA and reveals its mechanism of action in metabolic regulation, which may propose HMBA as a potential therapeutic strategy for obesity.
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Affiliation(s)
- Seokjae Park
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea
- Neurometabolomics Research Center, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea
| | - Sungjoon Oh
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea
- Neurometabolomics Research Center, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea
| | - Nayoun Kim
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea
| | - Eun-Kyoung Kim
- Department of Brain Sciences, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea
- Neurometabolomics Research Center, Daegu Gyeongbuk Institute of Science and Technology, Daegu, Korea
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Flavopiridol Mitigates the Progression of Monocrotaline-Induced Pulmonary Hypertension in Rats by Targeting Cyclin-Dependent Kinase 9. Cardiovasc Drugs Ther 2022; 37:449-460. [PMID: 35088192 PMCID: PMC10164032 DOI: 10.1007/s10557-021-07285-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 10/28/2021] [Indexed: 11/03/2022]
Abstract
PURPOSE To investigate the role of cyclin-dependent kinase 9 (CDK9) and the therapeutic potential of a CDK9 inhibitor (flavopiridol) in monocrotaline (MCT)-induced pulmonary hypertension (PH). METHODS For the in vivo experiments, rats with PH were established by a single intraperitoneal injection of MCT (60 mg/kg). After 2 weeks of MCT injection, rats were then treated with flavopiridol (5 mg/kg, i.p., twice a week) or vehicle for 2 weeks. For the in vitro experiments, human pulmonary artery smooth muscle cells (HPASMCs) were treated with flavopiridol (0.025-1 μM) or vehicle under hypoxic conditions. Hemodynamic recording, right ventricle histology, lung histology, and pulmonary arterial tissue isolation were performed. The expression levels of CDK9, RNA polymerase II, c-Myc, Mcl-1, and survivin were determined by qRT-PCR and western blotting, and the proliferation and apoptosis of rat pulmonary arterial tissues and/or HPASMCs were also assayed. RESULTS Compared to the control group, CDK9 was upregulated in pulmonary arterial tissues from MCT-induced PH rats and hypoxic cultured HPASMCs. Upregulation of CDK9 was associated with enhanced phosphorylation of the C-terminal domain (CTD) of RNA polymerase II (RNA pol II) at serine-2 (Ser-2), promoting the expression of prosurvival and antiapoptotic proteins (c-Myc, Mcl-1, and survivin). Furthermore, treatment with flavopiridol (5 mg/kg) significantly alleviated pulmonary artery remodeling and partially reversed the progression of MCT-induced PH. Consistently, flavopiridol (0.5 μM) treatment decreased the proliferation and induced the apoptosis of cultured HPASMCs under hypoxic conditions. As a result of CDK9 inhibition and subsequent inhibition of RNA pol II CTD phosphorylation at Ser-2, flavopiridol decreased c-Myc, Mcl-1, and survivin expression in isolated pulmonary small arteries, leading to cell growth inhibition and apoptosis. CONCLUSION Flavopiridol mitigates the progression of MCT-induced PH in rats by targeting CDK9.
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5
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Alam M, Ali S, Ashraf GM, Bilgrami AL, Yadav DK, Hassan MI. Epigallocatechin 3-gallate: From green tea to cancer therapeutics. Food Chem 2022; 379:132135. [PMID: 35063850 DOI: 10.1016/j.foodchem.2022.132135] [Citation(s) in RCA: 93] [Impact Index Per Article: 46.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Revised: 12/22/2021] [Accepted: 01/09/2022] [Indexed: 12/13/2022]
Abstract
Epigallocatechin 3-gallate (EGCG) possesses various biological functions, including anti-cancer and anti-inflammatory properties. EGCG is an abundant polyphenolic component originating from green tea extract that has exhibited versatile bioactivities in combating several cancers. This review highlights the pharmacological features of EGCG and its therapeutic implications in cancer and other metabolic diseases. It modulates numerous signaling pathways, regulating cells' undesired survival and proliferation, thus imparting strong tumor chemopreventive and therapeutic effects. EGCG initiates cell death through the intrinsic pathway and causes inhibition of EGFR, STAT3, and ERK pathways in several cancers. EGCG alters and inhibits ERK1/2, NF-κB, and Akt-mediated signaling, altering the Bcl-2 family proteins ratio and activating caspases in tumor cells. This review focuses on anti-cancer, anti-oxidant, anti-inflammatory, anti-angiogenesis, and apoptotic effects of EGCG. We further highlighted the potential of EGCG in different types of cancer, emphasizing clinical trials formulations that further improve our understanding of the therapeutic management of cancer and inflammatory diseases.
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Affiliation(s)
- Manzar Alam
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Sabeeha Ali
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India
| | - Ghulam Md Ashraf
- Pre-Clinical Research Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Anwar L Bilgrami
- Deanship of Scientific Research, King Abdulaziz University, Jeddah, Saudi Arabia
| | - Dharmendra Kumar Yadav
- College of Pharmacy, Gachon University of Medicine and Science, Hambakmoeiro, Yeonsu-gu, Incheon City 21924, South Korea.
| | - Md Imtaiyaz Hassan
- Centre for Interdisciplinary Research in Basic Sciences, Jamia Millia Islamia, New Delhi 110025, India.
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Mozar F, Sharma V, Gorityala S, Albert JM, Xu Y, Montano MM. Downregulation of Dihydrotestosterone and Estradiol Levels by HEXIM1. Endocrinology 2022; 163:bqab236. [PMID: 34864989 PMCID: PMC8645165 DOI: 10.1210/endocr/bqab236] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/02/2021] [Indexed: 11/19/2022]
Abstract
We have previously reported that hexamethylene bis-acetamide inducible protein 1 (HEXIM1) inhibits the activity of ligand-bound estrogen receptor α (ERα) and the androgen receptor (AR) by disrupting the interaction between these receptors and positive transcriptional elongation factor b (P-TEFb) and attenuating RNA polymerase II (RNAPII) phosphorylation at serine 2. Functional consequences of the inhibition of transcriptional activity of ERα and AR by HEXIM1 include the inhibition of ERα- and AR-dependent gene expression, respectively, and the resulting attenuation of breast cancer (BCa) and prostate cancer (PCa) cell proliferation and growth. In our present study, we determined that HEXIM1 inhibited AKR1C3 expression in BCa and PCa cells. AKR1C3, also known as 17β-hydroxysteroid dehydrogenase (17β-HSD) type 5, is a key enzyme involved in the synthesis of 17β-estradiol (E2) and 5-dihydrotestosterone (DHT). Downregulation of AKR1C3 by HEXIM1 influenced E2 and DHT production, estrogen- and androgen-dependent gene expression, and cell proliferation. Our studies indicate that HEXIM1 has the unique ability to inhibit both the transcriptional activity of the ER and AR and the synthesis of the endogenous ligands of these receptors.
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Affiliation(s)
- Fitya Mozar
- Department of Pharmacology; Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Vikas Sharma
- Department of Pharmacology; Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Shashank Gorityala
- Department of Chemistry, Cleveland State University, Cleveland, OH 44115, USA
| | - Jeffrey M Albert
- Department of Population and Quantitative Health Sciences, Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
| | - Yan Xu
- Department of Chemistry, Cleveland State University, Cleveland, OH 44115, USA
| | - Monica M Montano
- Department of Pharmacology; Case Western Reserve University School of Medicine, Cleveland, Ohio 44106, USA
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7
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Yang Y, Yeung KF, Liu J. CoMM-S 4: A Collaborative Mixed Model Using Summary-Level eQTL and GWAS Datasets in Transcriptome-Wide Association Studies. Front Genet 2021; 12:704538. [PMID: 34616426 PMCID: PMC8488198 DOI: 10.3389/fgene.2021.704538] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2021] [Accepted: 09/03/2021] [Indexed: 11/13/2022] Open
Abstract
Motivation: Genome-wide association studies (GWAS) have achieved remarkable success in identifying SNP-trait associations in the last decade. However, it is challenging to identify the mechanisms that connect the genetic variants with complex traits as the majority of GWAS associations are in non-coding regions. Methods that integrate genomic and transcriptomic data allow us to investigate how genetic variants may affect a trait through their effect on gene expression. These include CoMM and CoMM-S2, likelihood-ratio-based methods that integrate GWAS and eQTL studies to assess expression-trait association. However, their reliance on individual-level eQTL data render them inapplicable when only summary-level eQTL results, such as those from large-scale eQTL analyses, are available. Result: We develop an efficient probabilistic model, CoMM-S4, to explore the expression-trait association using summary-level eQTL and GWAS datasets. Compared with CoMM-S2, which uses individual-level eQTL data, CoMM-S4 requires only summary-level eQTL data. To test expression-trait association, an efficient variational Bayesian EM algorithm and a likelihood ratio test were constructed. We applied CoMM-S4 to both simulated and real data. The simulation results demonstrate that CoMM-S4 can perform as well as CoMM-S2 and S-PrediXcan, and analyses using GWAS summary statistics from Biobank Japan and eQTL summary statistics from eQTLGen and GTEx suggest novel susceptibility loci for cardiovascular diseases and osteoporosis. Availability and implementation: The developed R package is available at https://github.com/gordonliu810822/CoMM.
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Affiliation(s)
- Yi Yang
- Centre for Quantitative Medicine, Program in Health Services and Systems Research, Duke-NUS Medical School, Singapore, Singapore
| | - Kar-Fu Yeung
- Centre for Quantitative Medicine, Program in Health Services and Systems Research, Duke-NUS Medical School, Singapore, Singapore
| | - Jin Liu
- Centre for Quantitative Medicine, Program in Health Services and Systems Research, Duke-NUS Medical School, Singapore, Singapore
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8
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Ma Z, Wang LZ, Cheng JT, Lam WST, Ma X, Xiang X, Wong ALA, Goh BC, Gong Q, Sethi G, Wang L. Targeting Hypoxia-Inducible Factor-1-Mediated Metastasis for Cancer Therapy. Antioxid Redox Signal 2021; 34:1484-1497. [PMID: 33198508 DOI: 10.1089/ars.2019.7935] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Abstract
Significance: Hypoxia is emerging as a crucial regulator of the tumor microenvironment; it governs the metastatic potential of multiple primary cancers. It is also potentially involved in the regulation of tumorigenesis, tumor metabolism, and proangiogenic activity. Recent Advances: A wealth of clinical data across a wide range of cancer types has revealed strong correlations between hypoxia or the overexpression of hypoxia-inducible transcription factors and the rates of distant metastases and poor prognoses. Hypoxia-inducible factor (HIF)-1α, one of the key regulatory molecules of the HIF-1 signaling pathways, is involved in multiple crucial steps in the metastatic cascade. Critical Issues: Here, we present recent findings on the roles of the HIF-1 complex in tumor metastasis and highlight the potential of HIF-1α as a target for abrogating tumor metastasis. Moreover, we systematically describe the regulatory role of HIF-1 at each step of the metastatic cascade. Finally, we present the most recent advances in potential pharmacological interventions and the development of specific HIF-1 inhibitors for blocking tumor metastasis. Future Directions: Well-designed clinical trials are urgently needed to validate the anti-metastatic activity of HIF-1 inhibitors discovered in preclinical models. Antioxid. Redox Signal. 34, 1484-1497.
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Affiliation(s)
- Zhaowu Ma
- Department of Immunology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, China.,The First School of Clinical Medicine, Health Science Center, Yangtze University, Nanhuan Road, Jingzhou, China
| | - Louis Zizhao Wang
- SingHealth Internal Medicine Residency Programme, Singapore General Hospital, Singapore, Singapore
| | - Jun-Ting Cheng
- Department of Immunology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, China.,The First School of Clinical Medicine, Health Science Center, Yangtze University, Nanhuan Road, Jingzhou, China
| | - Walter Sze Tung Lam
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Xiang Ma
- School of Pharmacy, Tongji Medical College, Huazhong University of Science and Technology, Wuhan, China
| | - Xiaoqiang Xiang
- Department of Clinical Pharmacy, School of Pharmacy, Fudan University, Shanghai, P.R. China
| | - Andrea Li-Ann Wong
- Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.,Department of Haematology-Oncology, National University Cancer Institute, Singapore, Singapore
| | - Boon Cher Goh
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore.,Department of Haematology-Oncology, National University Cancer Institute, Singapore, Singapore
| | - Quan Gong
- Department of Immunology, School of Basic Medicine, Health Science Center, Yangtze University, Jingzhou, China.,The First School of Clinical Medicine, Health Science Center, Yangtze University, Nanhuan Road, Jingzhou, China
| | - Gautam Sethi
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore
| | - Lingzhi Wang
- Department of Pharmacology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore, Singapore.,Cancer Science Institute of Singapore, National University of Singapore, Singapore, Singapore
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9
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Sharma V, Montano MM. Non-epigenetic induction of HEXIM1 by DNMT1 inhibitors and functional relevance. Sci Rep 2020; 10:21015. [PMID: 33273553 PMCID: PMC7713402 DOI: 10.1038/s41598-020-78058-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2020] [Accepted: 11/17/2020] [Indexed: 11/09/2022] Open
Abstract
We have been studying the role of Hexamethylene bisacetamide (HMBA) Induced Protein 1 (HEXIM1) as a tumor suppressor whose expression is decreased in breast and prostate cancer. The anti-cancer actions of HEXIM1 in melanomas and AML have been reported by other groups. Previous studies have shown that 5-Aza-2'deoxycytidine (5-AzadC), a DNMT1 inhibitor, induces re-expression of tumor suppressor genes by removing/erasing methylation marks from their promoters. Our studies highlighted another mechanism wherein 5-AzadC induced DNA damage, which then resulted in enhanced occupancy of NF-ĸB, P-TEFb, and serine 2 phosphorylated RNA Polymerase II on the HEXIM1 gene. As a consequence, 5-AzadC induced HEXIM1 expression in prostate cancer cell lines and triple negative breast cancers. 5-AzadC-induced DNA damage enhanced P-TEFb occupancy via a mechanism that involved activation of ATR and ATM and induction of NF-ĸB recruitment to the HEXIM1 promoter. Downregulation of NF-ĸB attenuated 5-AzadC-induced HEXIM1 expression in prostate and breast cancer cells. The functional relevance of 5-AzadC-induced HEXIM1 expression is revealed by studies showing the HEXIM1 is required for the induction of apoptosis. Collectively, our findings support a non-epigenetic mechanism for 5-AzadC-induced re-expression of HEXIM1 protein, and may contribute to the clinical efficacy of 5-AzadC.
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Affiliation(s)
- Vikas Sharma
- Department of Pharmacology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH, 44106, USA
| | - Monica M Montano
- Department of Pharmacology, School of Medicine, Case Western Reserve University, 10900 Euclid Ave., Cleveland, OH, 44106, USA.
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10
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Shao H, Zhu Q, Lu H, Chang A, Gao C, Zhou Q, Luo K. HEXIM1 controls P-TEFb processing and regulates drug sensitivity in triple-negative breast cancer. Mol Biol Cell 2020; 31:1867-1878. [PMID: 32520633 PMCID: PMC7525814 DOI: 10.1091/mbc.e19-12-0704] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2019] [Revised: 05/28/2020] [Accepted: 06/02/2020] [Indexed: 11/16/2022] Open
Abstract
The positive transcription elongation factor b (P-TEFb), composed of CDK9 and cyclin T, stimulates transcriptional elongation by RNA polymerase (Pol) II and regulates cell growth and differentiation. Recently, we demonstrated that P-TEFb also controls the expression of EMT regulators to promote breast cancer progression. In the nucleus, more than half of P-TEFb are sequestered in the inactive-state 7SK snRNP complex. Here, we show that the assembly of the 7SK snRNP is preceded by an intermediate complex between HEXIM1 and P-TEFb that allows transfer of the kinase active P-TEFb from Hsp90 to 7SK snRNP for its suppression. Down-regulation of HEXIM1 locks P-TEFb in the Hsp90 complex, keeping it in the active state to enhance breast cancer progression, but also rendering the cells highly sensitive to Hsp90 inhibition. Because HEXIM1 is often down-regulated in human triple-negative breast cancer (TNBC), these cells are particularly sensitive to Hsp90 inhibition. Our study provides a mechanistic explanation for the increased sensitivity of TNBC to Hsp90 inhibition.
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Affiliation(s)
- Hengyi Shao
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Qingwei Zhu
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Huasong Lu
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Amanda Chang
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Carol Gao
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Qiang Zhou
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
| | - Kunxin Luo
- Department of Molecular and Cell Biology, University of California, Berkeley, CA 94720
- Life Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720
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11
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(-)-Epigallocatechin-3-gallate (EGCG) attenuates salt-induced hypertension and renal injury in Dahl salt-sensitive rats. Sci Rep 2020; 10:4783. [PMID: 32179848 PMCID: PMC7075996 DOI: 10.1038/s41598-020-61794-6] [Citation(s) in RCA: 18] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2019] [Accepted: 03/03/2020] [Indexed: 12/23/2022] Open
Abstract
Epigallocatechin-3-gallate (EGCG), a main active catechin in green tea, was reported to attenuate renal injury and hypertension. However, its effects on salt-induced hypertension and renal injury remain unclear. In the present study, we explored its effects on hypertension and renal damage in Dahl rats with salt-sensitive hypertension. We found that EGCG could lower blood pressure after 6 weeks of oral administration, reduce 24 h urine protein levels and decrease creatinine clearance, and attenuate renal fibrosis, indicating that it could attenuate hypertension by protecting against renal damage. Furthermore, we studied the renal protective mechanisms of EGCG, revealing that it could lower malondialdehyde levels, reduce the numbers of infiltrated macrophages and T cells, and induce the apoptosis of NRK-49F cells. Considering that the 67 kD laminin receptor (67LR) binds to EGCG, its role in EGCG-induced fibroblast apoptosis was also investigated. The results showed that an anti-67LR antibody partially abrogated the apoptosis-inducing effects of EGCG on NRK-49F cells. In summary, EGCG may attenuate renal damage and salt-sensitive hypertension via exerting anti-oxidant, anti-inflammatory, and apoptosis-inducing effects on fibroblasts; the last effect is partially mediated by 67LR, suggesting that EGCG represents a potential strategy for treating salt-sensitive hypertension.
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Bowry A, Piberger AL, Rojas P, Saponaro M, Petermann E. BET Inhibition Induces HEXIM1- and RAD51-Dependent Conflicts between Transcription and Replication. Cell Rep 2019; 25:2061-2069.e4. [PMID: 30463005 PMCID: PMC6280123 DOI: 10.1016/j.celrep.2018.10.079] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Revised: 09/27/2018] [Accepted: 10/19/2018] [Indexed: 12/21/2022] Open
Abstract
BET bromodomain proteins are required for oncogenic transcription activities, and BET inhibitors have been rapidly advanced into clinical trials. Understanding the effects of BET inhibition on processes such as DNA replication will be important for future clinical applications. Here, we show that BET inhibition, and specifically inhibition of BRD4, causes replication stress through a rapid overall increase in RNA synthesis. We provide evidence that BET inhibition acts by releasing P-TEFb from its inhibitor HEXIM1, promoting interference between transcription and replication. Unusually, these transcription-replication conflicts do not activate the ATM/ATR-dependent DNA damage response but recruit the homologous recombination factor RAD51. Both HEXIM1 and RAD51 promote BET inhibitor-induced fork slowing but also prevent a DNA damage response. Our data suggest that BET inhibitors slow replication through concerted action of transcription and recombination machineries and shed light on the importance of replication stress in the action of this class of experimental cancer drugs.
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Affiliation(s)
- Akhil Bowry
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Ann Liza Piberger
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Patricia Rojas
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Marco Saponaro
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK
| | - Eva Petermann
- Institute of Cancer and Genomic Sciences, College of Medical and Dental Sciences, University of Birmingham, Birmingham B15 2TT, UK.
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13
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Montano MM, Yeh IJ, Chen Y, Hernandez C, Kiselar JG, de la Fuente M, Lawes AM, Nieman MT, Kiser PD, Jacobberger J, Exner AA, Lawes MC. Inhibition of the histone demethylase, KDM5B, directly induces re-expression of tumor suppressor protein HEXIM1 in cancer cells. Breast Cancer Res 2019; 21:138. [PMID: 31805991 PMCID: PMC6896798 DOI: 10.1186/s13058-019-1228-7] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2019] [Accepted: 11/14/2019] [Indexed: 01/07/2023] Open
Abstract
Background The tumor suppressor actions of hexamethylene bis-acetamide (HMBA)-inducible protein 1 (HEXIM1) in the breast, prostate, melanomas, and AML have been reported by our group and others. Increased HEXIM1 expression caused differentiation and inhibited proliferation and metastasis of cancer cells. Historically, HEXIM1 has been experimentally induced with the hybrid polar compound HMBA, but HMBA is a poor clinical candidate due to lack of a known target, poor pharmacological properties, and unfavorable ADMETox characteristics. Thus, HEXIM1 induction is an intriguing therapeutic approach to cancer treatment, but requires better chemical tools than HMBA. Methods We identified and verified KDM5B as a target of HEXIM1 inducers using a chemical proteomics approach, biotin–NeutrAvidin pull-down assays, surface plasmon resonance, and molecular docking. The regulation of HEXIM1 by KDM5B and KDM5B inhibitors was assessed using chromatin immunoprecipitation assays, RT-PCR, western blotting, and depletion of KDM5B with shRNAs. The regulation of breast cancer cell phenotype by KDM5B inhibitors was assessed using western blots, differentiation assays, proliferation assays, and a mouse model of breast cancer metastasis. The relative role of HEXIM1 in the action of KDM5B inhibitors was determined by depleting HEXIM1 using shRNAs followed by western blots, differentiation assays, and proliferation assays. Results We have identified a highly druggable target, KDM5B, which is inhibited by small molecule inducers of HEXIM1. RNAi knockdown of KDM5B induced HEXIM1 expression, thus validating the specific negative regulation of tumor suppressor HEXIM1 by the H3K4me3/2 demethylase KDM5B. Known inhibitors of KDM5B were also able to induce HEXIM1 expression, inhibit cell proliferation, induce differentiation, potentiate sensitivity to cancer chemotherapy, and inhibit breast tumor metastasis. Conclusion HMBA and 4a1 induce HEXIM1 expression by inhibiting KDM5B. Upregulation of HEXIM1 expression levels plays a critical role in the inhibition of proliferation of breast cancer cells using KDM5B inhibitors. Based on the novel molecular scaffolds that we identified which more potently induced HEXIM1 expression and data in support that KDM5B is a target of these compounds, we have opened up new lead discovery and optimization directions.
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Affiliation(s)
- Monica M Montano
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA. .,Oncostatyx, 11000 Cedar Avenue Suite 26, Cleveland, OH, 44106, USA.
| | - I-Ju Yeh
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Yinghua Chen
- Department of Physiology and Biophysics, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Chris Hernandez
- General Medical Sciences, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Janna G Kiselar
- Department of Radiology, and Center for Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Maria de la Fuente
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Adriane M Lawes
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Marvin T Nieman
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Philip D Kiser
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - James Jacobberger
- General Medical Sciences, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Agata A Exner
- Department of Radiology, and Center for Proteomics and Bioinformatics, Case Western Reserve University School of Medicine, 10900 Euclid Avenue, Cleveland, OH, 44106, USA
| | - Matthew C Lawes
- Oncostatyx, 11000 Cedar Avenue Suite 26, Cleveland, OH, 44106, USA
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Ho PL, Ong HK, Teo J, Ow DSW, Chao SH. HEXIM1 Peptide Exhibits Antimicrobial Activity Against Antibiotic Resistant Bacteria Through Guidance of Cell Penetrating Peptide. Front Microbiol 2019; 10:203. [PMID: 30800117 PMCID: PMC6376162 DOI: 10.3389/fmicb.2019.00203] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2018] [Accepted: 01/24/2019] [Indexed: 12/16/2022] Open
Abstract
The emergence of antibiotic resistant bacteria is one of the biggest threats to human health worldwide. In 2017, World Health Organization listed the world’s most dangerous antibiotic-resistant bacteria or “superbugs,” such as carbapenem-resistant Pseudomonas aeruginosa and Escherichia coli, indicating the highest priority needs for new antibiotics. The possibility that such infectious diseases may soon be untreatable, due to decreased antibiotic efficacy, creates an urgent need for novel and alternative antimicrobials. Antimicrobial peptides are naturally occurring small molecules found in the innate immunity of mammals, plants and bacteria, and are potentially therapeutic candidates against drug-resistant bacteria. In this study, we examine the antimicrobial activities of the cytotoxic peptides derived from the basic region (BR) of the human hexamethylene bisacetamide-inducible protein 1 (HEXIM1). We found that, when fused with a cell penetrating peptide, the HEXIM1 BR peptide and its derivative, BR-RRR12, exhibited inhibitory activities against selected “superbugs.” Negligible effects on the viability of human keratinocyte cell line were observed when the bactericidal dosages of HEXIM1 BR peptides were used. Different killing kinetics were observed between the membrane permeabilizing antimicrobial peptides and HEXIM1 BR peptides, suggesting that a different antimicrobial mechanism might be utilized by the HEXIM1 BR peptides. Using an in vitro translation system based on E. coli lysates, we found that HEXIM1 BR peptides blocked bacterial translation. Taken together, we identify the HEXIM1 BR peptide as a novel antimicrobial peptide with potent inhibitory activity against antibiotic-resistant “superbugs.”
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Affiliation(s)
- Pooi Leng Ho
- Microbial Cells, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore, Singapore
| | - Han Kee Ong
- Expression Engineering Groups, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore, Singapore
| | - Jeanette Teo
- Department of Laboratory Medicine, National University Hospital, Singapore, Singapore
| | - Dave Siak-Wei Ow
- Microbial Cells, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore, Singapore
| | - Sheng-Hao Chao
- Expression Engineering Groups, Bioprocessing Technology Institute, Agency for Science, Technology and Research, Singapore, Singapore.,Department of Microbiology and Immunology, National University of Singapore, Singapore, Singapore
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Molecular Targets of Epigallocatechin-Gallate (EGCG): A Special Focus on Signal Transduction and Cancer. Nutrients 2018; 10:nu10121936. [PMID: 30563268 PMCID: PMC6315581 DOI: 10.3390/nu10121936] [Citation(s) in RCA: 159] [Impact Index Per Article: 26.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/07/2018] [Revised: 11/30/2018] [Accepted: 12/04/2018] [Indexed: 12/15/2022] Open
Abstract
Green tea is a beverage that is widely consumed worldwide and is believed to exert effects on different diseases, including cancer. The major components of green tea are catechins, a family of polyphenols. Among them, epigallocatechin-gallate (EGCG) is the most abundant and biologically active. EGCG is widely studied for its anti-cancer properties. However, the cellular and molecular mechanisms explaining its action have not been completely understood, yet. EGCG is effective in vivo at micromolar concentrations, suggesting that its action is mediated by interaction with specific targets that are involved in the regulation of crucial steps of cell proliferation, survival, and metastatic spread. Recently, several proteins have been identified as EGCG direct interactors. Among them, the trans-membrane receptor 67LR has been identified as a high affinity EGCG receptor. 67LR is a master regulator of many pathways affecting cell proliferation or apoptosis, also regulating cancer stem cells (CSCs) activity. EGCG was also found to be interacting directly with Pin1, TGFR-II, and metalloproteinases (MMPs) (mainly MMP2 and MMP9), which respectively regulate EGCG-dependent inhibition of NF-kB, epithelial-mesenchimal transaction (EMT) and cellular invasion. EGCG interacts with DNA methyltransferases (DNMTs) and histone deacetylases (HDACs), which modulates epigenetic changes. The bulk of this novel knowledge provides information about the mechanisms of action of EGCG and may explain its onco-suppressive function. The identification of crucial signalling pathways that are related to cancer onset and progression whose master regulators interacts with EGCG may disclose intriguing pharmacological targets, and eventually lead to novel combined treatments in which EGCG acts synergistically with known drugs.
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16
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Manmuan S, Sakunrangsit N, Ketchart W. Salinomycin overcomes acquired tamoxifen resistance through AIB1 and inhibits cancer cell invasion in endocrine resistant breast cancer. Clin Exp Pharmacol Physiol 2017; 44:1042-1052. [PMID: 28656701 DOI: 10.1111/1440-1681.12806] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2017] [Revised: 06/21/2017] [Accepted: 06/22/2017] [Indexed: 01/09/2023]
Abstract
Salinomycin is a monocarboxylic polyether ionophore isolated from Streptomyces albus. It has been widely used as an antibiotic in veterinary medicine in poultry. A recent study demonstrated that salinomycin selectively inhibits human breast cancer stem cells; one possible mechanism of tamoxifen resistance. Our results show that salinomycin is effective in inhibiting MCF-7/LCC2 and MCF-7/LCC9 cell lines which are well-established endocrine resistant cells and has a synergistic effect in combination with tamoxifen using MTT proliferation assay. The inhibitory effect of salinomycin on the reduction of critical ER co-activator; amplified breast 1 (AIB1) mRNA and protein expression is overcoming tamoxifen resistance. Moreover, salinomycin significantly inhibits cell invasion in Matrigel invasion assay. The effect was mediated at least in part by the decrease of matrix metalopeptidase 9 (MMP-9) which is one critical enzyme facilitated in the cell invasion process. In conclusion, salinomycin should be developed as a novel agent used alone or in combination for endocrine-resistant breast cancer.
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Affiliation(s)
- Suwisit Manmuan
- Department of Pharmacology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Nithidol Sakunrangsit
- Department of Pharmacology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
| | - Wannarasmi Ketchart
- Department of Pharmacology, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand
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17
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Lama R, Gan C, Idippily N, Bobba V, Danielpour D, Montano M, Su B. HMBA is a putative HSP70 activator stimulating HEXIM1 expression that is down-regulated by estrogen. J Steroid Biochem Mol Biol 2017; 168:91-101. [PMID: 28213333 PMCID: PMC5699885 DOI: 10.1016/j.jsbmb.2017.02.008] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/29/2016] [Revised: 02/10/2017] [Accepted: 02/12/2017] [Indexed: 12/27/2022]
Abstract
Hexamethylene bis-acetamide inducible protein 1 (HEXIM1) is identified as a novel inhibitor of estrogen stimulated breast cell growth, and it suppresses estrogen receptor-α transcriptional activity. HEXIM1 protein level has been found to be downregulated by estrogens. Recently, HEXIM1 has been found to inhibit androgen receptor transcriptional activity as well. Researchers have used Hexamethylene bis-acetamide (HMBA) for decades to stimulate HEXIM1 expression, which also inhibit estrogen stimulated breast cancer cell gene activation and androgen stimulated prostate cancer gene activation. However, the direct molecular targets of HMBA that modulate the induction of HEXIM1 expression in mammalian cells have not been identified. Based on HMBA and its more potent analog 4a1, we designed molecular probes to pull down the binding proteins of these compounds. Via proteomic approach and biological assays, we demonstrate that HMBA and 4a1 are actually heat shock protein 70 (HSP70) binders. The known HSP70 activator showed similar activity as HMBA and 4a1 to induce HEXIM1 expression, suggesting that HMBA and 4a1 might be putative HSP70 activators. Molecular target identification of HMBA and 4a1 could lead to further structural optimization of the parental compound to generate more potent derivatives to stimulate HEXIM1 expression, which could be a novel approach for hormone dependent breast cancer and prostate cancer treatment.
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Affiliation(s)
- Rati Lama
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH, 44115, USA
| | - Chunfang Gan
- College of Chemistry and Material Science, Key Laboratory of Beibu Gulf Environment Change and Resources Utilization, Guangxi Teachers Education University, Nanning 530001, China
| | - Nethrie Idippily
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH, 44115, USA
| | - Viharika Bobba
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH, 44115, USA
| | - David Danielpour
- Division of General Medical Science-Oncology, Case Comprehensive Cancer Center, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Monica Montano
- Department of Pharmacology, Case Western Reserve University, Cleveland, OH 44106, USA
| | - Bin Su
- Department of Chemistry, Center for Gene Regulation in Health and Disease, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH, 44115, USA.
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18
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Tan JL, Fogley RD, Flynn RA, Ablain J, Yang S, Saint-André V, Fan ZP, Do BT, Laga AC, Fujinaga K, Santoriello C, Greer CB, Kim YJ, Clohessy JG, Bothmer A, Pandell N, Avagyan S, Brogie JE, van Rooijen E, Hagedorn EJ, Shyh-Chang N, White RM, Price DH, Pandolfi PP, Peterlin BM, Zhou Y, Kim TH, Asara JM, Chang HY, Young RA, Zon LI. Stress from Nucleotide Depletion Activates the Transcriptional Regulator HEXIM1 to Suppress Melanoma. Mol Cell 2016; 62:34-46. [PMID: 27058786 DOI: 10.1016/j.molcel.2016.03.013] [Citation(s) in RCA: 58] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2015] [Revised: 02/02/2016] [Accepted: 03/10/2016] [Indexed: 12/29/2022]
Abstract
Studying cancer metabolism gives insight into tumorigenic survival mechanisms and susceptibilities. In melanoma, we identify HEXIM1, a transcription elongation regulator, as a melanoma tumor suppressor that responds to nucleotide stress. HEXIM1 expression is low in melanoma. Its overexpression in a zebrafish melanoma model suppresses cancer formation, while its inactivation accelerates tumor onset in vivo. Knockdown of HEXIM1 rescues zebrafish neural crest defects and human melanoma proliferation defects that arise from nucleotide depletion. Under nucleotide stress, HEXIM1 is induced to form an inhibitory complex with P-TEFb, the kinase that initiates transcription elongation, to inhibit elongation at tumorigenic genes. The resulting alteration in gene expression also causes anti-tumorigenic RNAs to bind to and be stabilized by HEXIM1. HEXIM1 plays an important role in inhibiting cancer cell-specific gene transcription while also facilitating anti-cancer gene expression. Our study reveals an important role for HEXIM1 in coupling nucleotide metabolism with transcriptional regulation in melanoma.
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Affiliation(s)
- Justin L Tan
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Rachel D Fogley
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Ryan A Flynn
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Julien Ablain
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Song Yang
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Violaine Saint-André
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Zi Peng Fan
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Brian T Do
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Alvaro C Laga
- Department of Pathology, Brigham & Women's Hospital, Boston, MA 02215, USA
| | - Koh Fujinaga
- Departments of Medicine, Microbiology, and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Cristina Santoriello
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Celeste B Greer
- Department of Pharmacology, School of Medicine, Yale University, New Haven, CT 06520, USA
| | - Yoon Jung Kim
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX 75080, USA
| | - John G Clohessy
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, and Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA; Preclinical Murine Pharmacogenetics Facility, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Anne Bothmer
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, and Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Nicole Pandell
- Preclinical Murine Pharmacogenetics Facility, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - Serine Avagyan
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - John E Brogie
- Department of Biochemistry, University of Iowa, Iowa City, IA 52242, USA
| | - Ellen van Rooijen
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Elliott J Hagedorn
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Ng Shyh-Chang
- Genome Institute of Singapore, 60 Biopolis Street, Singapore 138672, Singapore
| | - Richard M White
- Memorial Sloan Kettering Cancer Center and Weill Cornell Medical College, New York, NY 10065, USA
| | - David H Price
- Department of Biochemistry, University of Iowa, Iowa City, IA 52242, USA
| | - Pier Paolo Pandolfi
- Cancer Research Institute, Beth Israel Deaconess Cancer Center, and Department of Medicine and Pathology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02115, USA
| | - B Matija Peterlin
- Departments of Medicine, Microbiology, and Immunology, University of California, San Francisco, San Francisco, CA 94143, USA
| | - Yi Zhou
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA
| | - Tae Hoon Kim
- Department of Biological Sciences, The University of Texas at Dallas, Richardson, TX 75080, USA
| | - John M Asara
- Division of Signal Transduction, Department of Medicine, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA 02215, USA
| | - Howard Y Chang
- Center for Personal Dynamic Regulomes, Stanford University School of Medicine, Stanford, CA 94305, USA
| | - Richard A Young
- Whitehead Institute for Biomedical Research and Department of Biology, Massachusetts Institute of Technology, Cambridge, MA 02142, USA
| | - Leonard I Zon
- Howard Hughes Medical Institute, Stem Cell Program and Division of Pediatric Hematology/Oncology, Boston Children's Hospital, Dana-Farber Cancer Institute, Harvard Medical School, Boston, MA 02115, USA; Department of Stem Cell and Regenerative Biology, Harvard Stem Cell Institute, Cambridge, MA 02138, USA.
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Induction of HEXIM1 activities by HMBA derivative 4a1: Functional consequences and mechanism. Cancer Lett 2016; 379:60-9. [PMID: 27238569 DOI: 10.1016/j.canlet.2016.05.029] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2016] [Revised: 05/23/2016] [Accepted: 05/25/2016] [Indexed: 12/16/2022]
Abstract
We have been studying the role of Hexamethylene bisacetamide (HMBA) Induced Protein 1 (HEXIM1) as a tumor suppressor whose expression is decreased in tamoxifen resistant and metastatic breast cancer. HMBA was considered the most potent and specific inducer for HMBA inducible protein 1 (HEXIM1) prior to our studies. Moreover, the ability of HMBA to induce differentiation is advantageous for its therapeutic use when compared to cytotoxic agents. However, HMBA induced HEXIM1 expression required at mM concentrations and induced dose limiting toxicity, thrombocytopenia. Thus we structurally optimized HMBA and identified a more potent inducer of HEXIM1 expression, 4a1. The studies reported herein tested the ability of 4a1 to induce HEXIM1 activities using a combination of biochemical, cell phenotypic, and in vivo assays. 4a1 induced breast cell differentiation, including the stem cell fraction in triple negative breast cancer cells. Clinically relevant HEXIM1 activities that are also induced by 4a1 include enhancement of the inhibitory effects of tamoxifen and inhibition of breast tumor metastasis. We also provide mechanistic basis for the phenotypic effects of 4a1. Our results support the potential of an unsymmetrical HMBA derivative, such as 4a1, as lead compound for further drug development.
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20
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DiGiacomo V, Meruelo D. Looking into laminin receptor: critical discussion regarding the non-integrin 37/67-kDa laminin receptor/RPSA protein. Biol Rev Camb Philos Soc 2015; 91:288-310. [PMID: 25630983 DOI: 10.1111/brv.12170] [Citation(s) in RCA: 94] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2013] [Revised: 12/04/2014] [Accepted: 12/08/2014] [Indexed: 02/06/2023]
Abstract
The 37/67-kDa laminin receptor (LAMR/RPSA) was originally identified as a 67-kDa binding protein for laminin, an extracellular matrix glycoprotein that provides cellular adhesion to the basement membrane. LAMR has evolutionary origins, however, as a 37-kDa RPS2 family ribosomal component. Expressed in all domains of life, RPS2 proteins have been shown to have remarkably diverse physiological roles that vary across species. Contributing to laminin binding, ribosome biogenesis, cytoskeletal organization, and nuclear functions, this protein governs critical cellular processes including growth, survival, migration, protein synthesis, development, and differentiation. Unsurprisingly given its purview, LAMR has been associated with metastatic cancer, neurodegenerative disease and developmental abnormalities. Functioning in a receptor capacity, this protein also confers susceptibility to bacterial and viral infection. LAMR is clearly a molecule of consequence in human disease, directly mediating pathological events that make it a prime target for therapeutic interventions. Despite decades of research, there are still a large number of open questions regarding the cellular biology of LAMR, the nature of its ability to bind laminin, the function of its intrinsically disordered C-terminal region and its conversion from 37 to 67 kDa. This review attempts to convey an in-depth description of the complexity surrounding this multifaceted protein across functional, structural and pathological aspects.
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Affiliation(s)
- Vincent DiGiacomo
- Department of Pathology, New York University School of Medicine, 180 Varick Street, New York, NY 10014, U.S.A
| | - Daniel Meruelo
- Department of Pathology, New York University School of Medicine, 180 Varick Street, New York, NY 10014, U.S.A.,NYU Cancer Institute, 550 First Avenue, New York, NY 10016, U.S.A.,NYU Gene Therapy Center, 550 First Avenue, New York, NY 10016, U.S.A
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21
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HEXIM1 plays a critical role in the inhibition of the androgen receptor by anti-androgens. Biochem J 2014; 462:315-27. [PMID: 24844355 DOI: 10.1042/bj20140174] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
We show that HEXIM1 (hexamethylene bis-acetamide inducible 1) functions as an AR (androgen receptor) co-repressor as it physically interacts with the AR and is required for the ability of anti-androgens to inhibit androgen-induced target gene expression and cell proliferation. Oncomine™ database and IHC (immunohistochemistry) analyses of human prostate tissues revealed that expression of HEXIM1 mRNA and protein are down-regulated during the development and progression of prostate cancer. Enforced down-regulation of HEXIM1 in parental hormone-dependent LNCaP cells results in resistance to the inhibitory action of anti-androgens. Conversely, ectopic expression of HEXIM1 in the CRPC (castration-resistant prostate cancer) cell line, C4-2, enhances their sensitivity to the repressive effects of the anti-androgen bicalutamide. Novel insight into the mechanistic basis for HEXIM1 inhibition of AR activity is provided by the present studies showing that HEXIM1 induces expression of the histone demethylase KDM5B (lysine-specific demethylase 5B) and inhibits histone methylation, resulting in the inhibition of FOXA1 (forkhead box A1) licensing activity. This is a new mechanism of action attributed to HEXIM1, and distinct from what has been reported so far to be involved in HEXIM1 regulation of other nuclear hormone receptors, including the oestrogen receptor.
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22
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Yoshikawa N, Shimizu N, Ojima H, Kobayashi H, Hosono O, Tanaka H. Down-regulation of hypoxia-inducible factor-1 alpha and vascular endothelial growth factor by HEXIM1 attenuates myocardial angiogenesis in hypoxic mice. Biochem Biophys Res Commun 2014; 453:600-5. [DOI: 10.1016/j.bbrc.2014.09.135] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2014] [Accepted: 09/30/2014] [Indexed: 11/29/2022]
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23
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Brd4 and HEXIM1: multiple roles in P-TEFb regulation and cancer. BIOMED RESEARCH INTERNATIONAL 2014; 2014:232870. [PMID: 24592384 PMCID: PMC3925632 DOI: 10.1155/2014/232870] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/06/2013] [Accepted: 12/19/2013] [Indexed: 12/31/2022]
Abstract
Bromodomain-containing protein 4 (Brd4) and hexamethylene bisacetamide (HMBA) inducible protein 1 (HEXIM1) are two opposing regulators of the positive transcription elongation factor b (P-TEFb), which is the master modulator of RNA polymerase II during transcriptional elongation. While Brd4 recruits P-TEFb to promoter-proximal chromatins to activate transcription, HEXIM1 sequesters P-TEFb into an inactive complex containing the 7SK small nuclear RNA. Besides regulating P-TEFb's transcriptional activity, recent evidence demonstrates that both Brd4 and HEXIM1 also play novel roles in cell cycle progression and tumorigenesis. Here we will discuss the current knowledge on Brd4 and HEXIM1 and their implication as novel therapeutic options against cancer.
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Zhong B, Lama R, Ketchart W, Montano MM, Su B. Lead optimization of HMBA to develop potent HEXIM1 inducers. Bioorg Med Chem Lett 2014; 24:1410-3. [PMID: 24503105 DOI: 10.1016/j.bmcl.2014.01.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2013] [Revised: 01/07/2014] [Accepted: 01/09/2014] [Indexed: 12/20/2022]
Abstract
The potency of a series of Hexamethylene bis-acetamide (HMBA) derivatives inducing Hexamethylene bis-acetamide inducible protein 1 (HEXIM1) was determined in LNCaP prostate cancer cells. Several compounds with unsymmetrical structures showed significantly improved activity. Distinct from HMBA, these analogs have increased hydrophobicity and can improve the short half-life of HMBA, which is one of the factors that have limited the application of HMBA in clinics. The unsymmetrical scaffolds of the new analogs provide the basis for further lead optimization of the compounds using combinatorial chemistry strategy.
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Affiliation(s)
- Bo Zhong
- Department of Chemistry, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH 44115, USA
| | - Rati Lama
- Department of Chemistry, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH 44115, USA
| | - Wannarasmi Ketchart
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106, USA
| | - Monica M Montano
- Department of Pharmacology, Case Western Reserve University School of Medicine, 10900 Euclid Ave., Cleveland, OH 44106, USA.
| | - Bin Su
- Department of Chemistry, College of Sciences and Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH 44115, USA; Center for Gene Regulation in Health and Disease, College of Sciences & Health Professions, Cleveland State University, 2121 Euclid Ave., Cleveland, OH 44115, USA.
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25
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Abstract
We have previously reported on the inhibition of HIF-1α (hypoxia-inducible factor α)-regulated pathways by HEXIM1 [HMBA (hexamethylene-bis-acetamide)-inducible protein 1]. Disruption of HEXIM1 activity in a knock-in mouse model expressing a mutant HEXIM1 protein resulted in increased susceptibility to the development of mammary tumours, partly by up-regulation of VEGF (vascular endothelial growth factor) expression, HIF-1α expression and aberrant vascularization. We now report on the mechanistic basis for HEXIM1 regulation of HIF-1α. We observed direct interaction between HIF-1α and HEXIM1, and HEXIM1 up-regulated hydroxylation of HIF-1α, resulting in the induction of the interaction of HIF-1α with pVHL (von Hippel-Lindau protein) and ubiquitination of HIF-1α. The up-regulation of hydroxylation involves HEXIM1-mediated induction of PHD3 (prolyl hydroxylase 3) expression and interaction of PHD3 with HIF-1α. Acetylation of HIF-1α has been proposed to result in increased interaction of HIF-1α with pVHL and induced pVHL-mediated ubiquitination, which leads to the proteasomal degradation of HIF-1α. HEXIM1 also attenuated the interaction of HIF-1α with HDAC1 (histone deacetylase 1), resulting in acetylation of HIF-1α. The consequence of HEXIM1 down-regulation of HIF-1α protein expression is attenuated expression of HIF-1α target genes in addition to VEGF and inhibition of HIF-1α-regulated cell invasion.
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26
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Affiliation(s)
- Jiannan Guo
- Biochemistry Department, University of Iowa , Iowa City, Iowa 52242, United States
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27
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Kim Y, Wu Q, Hamerlik P, Hitomi M, Sloan AE, Barnett GH, Weil RJ, Leahy P, Hjelmeland AB, Rich JN. Aptamer identification of brain tumor-initiating cells. Cancer Res 2013; 73:4923-36. [PMID: 23796560 DOI: 10.1158/0008-5472.can-12-4556] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Glioblastomas display cellular hierarchies with self-renewing tumor-initiating cells (TIC), also known as cancer stem cells, at the apex. Although the TIC hypothesis remains controversial and the functional assays to define the TIC phenotype are evolving, we and others have shown that TICs may contribute to therapeutic resistance, tumor spread, and angiogenesis. The identification of TICs has been informed by the use of markers characterized in normal stem cells, but this approach has an inherent limitation to selectively identify TICs. To develop reagents that enrich TICs but not matched non-TICs or tissue-specific stem cells, we adopted Cell-Systematic Evolution of Ligands by Exponential Enrichment (Cell-SELEX) to identify glioblastoma TIC-specific nucleic acid probes-aptamers-that specifically bind TICs. In this study, using Cell-SELEX with positive selection for TICs and negative selection for non-TICs and human neural progenitor cells, we identified TIC aptamers that specifically bind to TICs with excellent dissociation constants (Kd). These aptamers select and internalize into glioblastoma cells that self-renew, proliferate, and initiate tumors. As aptamers can be modified to deliver payloads, aptamers may represent novel agents that could selectively target or facilitate imaging of TICs.
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Affiliation(s)
- Youngmi Kim
- Department of Stem Cell Biology & Regenerative Medicine, Lerner Research Institute, Cleveland Clinic, 9500 Euclid Ave., NE3-301, Cleveland, OH 44195, USA
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