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Creighton CJ, Zhang F, Zhang Y, Castro P, Hu R, Islam M, Ghosh S, Ittmann M, Kwabi-Addo B. Comparative and integrative analysis of transcriptomic and epigenomic-wide DNA methylation changes in African American prostate cancer. Epigenetics 2023. [DOI: 10.1080/15592294.2023.2180585] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/24/2023] Open
Affiliation(s)
- Chad J. Creighton
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Flora Zhang
- Center for Women’s Studies, Colgate University, Hamilton, New York, USA
| | - Yiqun Zhang
- Dan L. Duncan Comprehensive Cancer Center, Baylor College of Medicine, Houston, TX, USA
| | - Patricia Castro
- Department of Pathology and Immunology, Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas, USA
| | - Rong Hu
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia, USA
| | - Md Islam
- Lombardi Comprehensive Cancer Center, Georgetown University, Washington, District of Columbia, USA
| | - Somiranjan Ghosh
- Department of Biology, Howard University, Washington, Columbia, USA
| | - Michael Ittmann
- Department of Pathology and Immunology, Michael E. DeBakey Veterans Affairs Medical Center, Houston, Texas, USA
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, Howard University, Washington, Columbia, USA
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Khan M, Hearn K, Parry C, Rasid M, Brim H, Ashktorab H, Kwabi-Addo B. Mechanism of Antitumor Effects of Saffron in Human Prostate Cancer Cells. Nutrients 2023; 16:114. [PMID: 38201944 PMCID: PMC10780623 DOI: 10.3390/nu16010114] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2023] [Revised: 12/26/2023] [Accepted: 12/27/2023] [Indexed: 01/12/2024] Open
Abstract
Prostate cancer is the most common cancer and the second leading cause of cancer deaths among men in the USA. Several studies have demonstrated the antitumor properties of saffron in different types of cancers, including prostate cancer. The oral administration of saffron extract has been reported to have antitumor effects on aggressive prostate-cancer-cell-line-derived xenografts in nude male mice. The objective of this study was to carry out in vitro studies of saffron-treated prostate cancer cells to ascertain the effects of saffron on key intermediates in prostate carcinogenesis. Our studies demonstrated the significant inhibition of cell proliferation for androgen-sensitive prostate cancer cell lines via apoptotic pathways. We also demonstrate the statistically significant down-regulation of DNA methyltransferases (COMT, MGMT, EHMT2, and SIRT1 deacetylase) in saffron-treated prostate cancer cells. In addition, saffron-treated prostate cancer cells displayed a statistically significant dysregulation of DNA repair intermediates (WRN, p53, RECQ5, MST1R, and WDR70) in a time-dependent manner. Furthermore, Western blot analysis demonstrated that saffron treatment induced changes in the expression of other key genes (DNMT1, DNMT3b, MBD2, CD44, HDAC3, c-Myc, NF-kB, TNFα, AR, N-RAS, and PTEN) in prostate cancer cells. Collectively, our findings demonstrate the important mechanisms by which saffron mediates anti-tumor properties in prostate cancer. These findings suggest that the use of saffron supplements alongside standard treatment protocols may yield beneficial effects for individuals with prostate cancer.
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Affiliation(s)
- Mohammad Khan
- Department of Biochemistry and Molecular Biology, Howard University, Washington, DC 20059, USA
| | - Kaitlyn Hearn
- Department of Life Sciences, Xavier University of Louisiana, New Orleans, LA 70125, USA;
| | - Christian Parry
- Department of Microbiology, Howard University, Washington, DC 20059, USA;
| | - Mudasir Rasid
- Cancer Center, Howard University, Washington, DC 20059, USA; (M.R.); (H.A.)
| | - Hassan Brim
- Department of Pathology, Howard University, Washington, DC 20059, USA;
| | - Hassan Ashktorab
- Cancer Center, Howard University, Washington, DC 20059, USA; (M.R.); (H.A.)
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, Howard University, Washington, DC 20059, USA
- Cancer Center, Howard University, Washington, DC 20059, USA; (M.R.); (H.A.)
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Mondal T, Smith CI, Loffredo CA, Quartey R, Moses G, Howell CD, Korba B, Kwabi-Addo B, Nunlee-Bland G, R. Rucker L, Johnson J, Ghosh S. Transcriptomics of MASLD Pathobiology in African American Patients in the Washington DC Area †. Int J Mol Sci 2023; 24:16654. [PMID: 38068980 PMCID: PMC10706626 DOI: 10.3390/ijms242316654] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 11/17/2023] [Accepted: 11/18/2023] [Indexed: 12/18/2023] Open
Abstract
Metabolic-dysfunction-associated steatotic liver disease (MASLD) is becoming the most common chronic liver disease worldwide and is of concern among African Americans (AA) in the United States. This pilot study evaluated the differential gene expressions and identified the signature genes in the disease pathways of AA individuals with MASLD. Blood samples were obtained from MASLD patients (n = 23) and non-MASLD controls (n = 24) along with their sociodemographic and medical details. Whole-blood transcriptomic analysis was carried out using Affymetrix Clarion-S Assay. A validation study was performed utilizing TaqMan Arrays coupled with Ingenuity Pathway Analysis (IPA) to identify the major disease pathways. Out of 21,448 genes in total, 535 genes (2.5%) were significantly (p < 0.05) and differentially expressed when we compared the cases and controls. A significant overlap in the predominant differentially expressed genes and pathways identified in previous studies using hepatic tissue was observed. Of note, TGFB1 and E2F1 genes were upregulated, and HMBS was downregulated significantly. Hepatic fibrosis signaling is the top canonical pathway, and its corresponding biofunction contributes to the development of hepatocellular carcinoma. The findings address the knowledge gaps regarding how signature genes and functional pathways can be detected in blood samples ('liquid biopsy') in AA MASLD patients, demonstrating the potential of the blood samples as an alternative non-invasive source of material for future studies.
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Affiliation(s)
- Tanmoy Mondal
- Department of Biology, Howard University, Washington, DC 20059, USA; (T.M.); (G.M.); (J.J.)
| | - Coleman I. Smith
- MedStar-Georgetown Transplantation Institute, Georgetown University School of Medicine, Washington, DC 20007, USA;
| | | | - Ruth Quartey
- Department of Internal Medicine, College of Medicine, Howard University, Washington, DC 20007, USA; (R.Q.); (C.D.H.)
| | - Gemeyel Moses
- Department of Biology, Howard University, Washington, DC 20059, USA; (T.M.); (G.M.); (J.J.)
| | - Charles D. Howell
- Department of Internal Medicine, College of Medicine, Howard University, Washington, DC 20007, USA; (R.Q.); (C.D.H.)
| | - Brent Korba
- Department of Microbiology & Immunology, Georgetown University, Washington, DC 20007, USA;
| | - Bernard Kwabi-Addo
- Department of Biochemistry, College of Medicine, Howard University, Washington, DC 20059, USA;
| | - Gail Nunlee-Bland
- Departments of Pediatrics and Child Health, College of Medicine, Howard University, Washington, DC 20059, USA;
| | - Leanna R. Rucker
- Department of Internal Medicine, MedStar Georgetown University Hospital, Washington, DC 20007, USA;
| | - Jheannelle Johnson
- Department of Biology, Howard University, Washington, DC 20059, USA; (T.M.); (G.M.); (J.J.)
| | - Somiranjan Ghosh
- Department of Biology, Howard University, Washington, DC 20059, USA; (T.M.); (G.M.); (J.J.)
- Departments of Pediatrics and Child Health, College of Medicine, Howard University, Washington, DC 20059, USA;
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Kwabi-Addo B, Ghosh S, Creighton C, Ittmann M. Abstract 5999: Comparative and integrative analysis of transcriptomic and epigenome wide DNA methylation changes in African American prostate cancer. Cancer Res 2023. [DOI: 10.1158/1538-7445.am2023-5999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/07/2023]
Abstract
Abstract
African American (AA) men have the highest incidence and mortality rate from Prostate cancer (PCa) than any other racial/ethnic group. To understand this racial disparity, molecular features of different types, including gene expression, DNA methylation and other genomic alterations, must be carried out in tumor samples from these 2 populations. To date, PCa genomic studies have largely under-represented tumor samples from AA men due to lack of inclusion of significant numbers in such studies. In this study we carried out genome-wide DNA methylation analysis in 63 clinically annotated fresh-frozen PCa and 50 normal prostate tissues from AA men using the Illumina Infunium 850K Human Methylation EPIC BeadChip array. mRNA expression database from a sub-set of the AA biospecimen were used to assess correlation of transcriptome and epigenomic datasets. Using bioinformatic analysis to integrate a comprehensive set of genomic datasets we identified probesets that were significant (p<0.01) and differentially methylated in AA PCa compared to normal prostate tissues and were significant (p<0.01) and inversely correlated with AA mRNA expression. GO analysis in this AA cohort showed significant differential methylation that were mostly hypermethylated genes with corresponding down-regulated mRNA expression for top genes associated with biological pathways in hemidesmosome assembly, mammary gland development, epidermis development, hormone biosynthetic process and cell communication. On the other hand, few significant differential top hypomethylated genes and corresponding up-regulated mRNA expression were identified in biological pathways of negative regulation of macrophage differentiation, cAMP-dependent protein kinase inhibitor activity, protein destabilization, transcription corepressor activity and fatty acid biosynthetic process. Furthermore, we identified significant and differential methylated genes in our AA PCa cohort that were associated with PCa progression when compared to the TCGA EA and AA dataset. These genes were AMIGO3, IER3, UPB1, GRM7, TFAP2C, TOX2, PLSCR2, ZNF292, ESR2, MIXL1, BOLL and FGF6. Overall, IPA of differential methylated promoter region are genes enriched for network involved in sex-steroid hormonal signals and tumor microenvironment signaling pathways. Our integrative analysis provides new candidate genes associated with prostate cancer progression in AA men as potential targets for improving prostate cancer treatment and addressing the racial disparity problem.
Citation Format: Bernard Kwabi-Addo, Somiranjan Ghosh, Chad Creighton, Michael Ittmann. Comparative and integrative analysis of transcriptomic and epigenome wide DNA methylation changes in African American prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2023; Part 1 (Regular and Invited Abstracts); 2023 Apr 14-19; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2023;83(7_Suppl):Abstract nr 5999.
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Saadatmand F, Abbas M, Apprey V, Tailor K, Kwabi-Addo B. Sex differences in saliva-based DNA methylation changes and environmental stressor in young African American adults. PLoS One 2022; 17:e0273717. [PMID: 36067197 PMCID: PMC9447871 DOI: 10.1371/journal.pone.0273717] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/20/2022] [Accepted: 08/02/2022] [Indexed: 11/21/2022] Open
Abstract
BACKGROUND Low socioeconomic status neighborhood exposure to stress and violence may be sources of negative stimuli that poses significant health risks for children, adolescents and throughout the life course of an individual. The study aims to investigate if aberrant epigenetic DNA methylation changes may be a potential mechanism for regulating neighborhood exposures and health outcomes. METHODS Exposure to environmental stressors identified in 98 young African American (AA) adults aged 18-25 years old from the Washington D.C., area were used in the study. We correlated the association between stress markers; cortisol, CRP, IgG, IGA, IgM, and self-reported exposure to violence and stress, with quantitative DNA methylation changes in a panel of gene-specific loci using saliva DNA. RESULTS In all participants studied, the exposure to violence was significant and negatively correlated with DNA methylation of MST1R loci (p = 0.032; r = -0.971) and nominally significant with NR3C1 loci (p = 0.053; r = -0.948). In addition, we observed significant and negative correlation of DNA methylation changes of LINE1 (p = 0.044; r = -0.248); NR3C1 (p = 0.017; r = -0.186); MSTR1 (p = 0.022; r = -0.192); and DRD2 (p = 0.056; r = -0.184; albeit nominal significant correlation) with IgA expression. On the other hand, we observed a significant and position correlation of DNA methylation changes in DRD2 (p = 0.037; r = 0.184) with IgG expression. When participants were stratified by sex, we observed in AA young male adults, significant DNA methylation changes of MST1R (p< 0.05) and association with exposure to violence and IgG level. We also observed significant DNA methylation levels of DRD2 (p< 0.05) and association with IgA, IgG, and cortisol level. Furthermore, we observed significant DNA methylation changes of NR3C1 (p< 0.05) with stress, IgA, and IgG in the male participants only. On the other hand, we only observed significant and a positive association of IgG with DNA methylation levels of ESR1 (p = 0.041) in the young AA female participants. CONCLUSION Our preliminary observation of significant DNA methylation changes in neuronal and immune genes in saliva samples supports our recently published genome-wide DNA methylations changes in blood samples from young AA male adults indicating that saliva offers a non-invasive means for DNA methylation prediction of exposure to environmental stressors in a gender-specific manner.
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Affiliation(s)
- Forough Saadatmand
- Department of Pediatrics, Howard University, Washington, D.C., United States of America
| | - Muneer Abbas
- Department of Microbiology & The National Human Genome Center, Howard University, Washington, D.C., United States of America
| | - Victor Apprey
- Department of Biochemistry and Molecular Biology, College of Medicine, Howard University, Washington, D.C., United States of America
| | - Krishma Tailor
- Department of Biochemistry and Molecular Biology, College of Medicine, Howard University, Washington, D.C., United States of America
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, College of Medicine, Howard University, Washington, D.C., United States of America
- * E-mail:
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Ngwa JS, Nwulia E, Ntekim O, Bedada FB, Kwabi-Addo B, Nadarajah S, Johnson S, Southerland WM, Kwagyan J, Obisesan TO. Aerobic Exercise Training-Induced Changes on DNA Methylation in Mild Cognitively Impaired Elderly African Americans: Gene, Exercise, and Memory Study - GEMS-I. Front Mol Neurosci 2022; 14:752403. [PMID: 35110995 PMCID: PMC8802631 DOI: 10.3389/fnmol.2021.752403] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Accepted: 12/16/2021] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND DNA methylation at CpG sites is a vital epigenetic modification of the human genome affecting gene expression, and potentially, health outcomes. However, evidence is just budding on the effects of aerobic exercise-induced adaptation on DNA methylation in older mild cognitively impaired (MCI) elderly African American (AAs). Therefore, we examined the effects of a 6-month aerobic exercise-intervention on genome-wide DNA methylation in elderly AA MCI volunteers. DESIGN Elderly AA volunteers confirmed MCI assigned into a 6-month program of aerobic exercise (eleven participants) underwent a 40-min supervised-training 3-times/week and controls (eight participants) performed stretch training. Participants had maximal oxygen consumption (VO2max) test and Genome-wide methylation levels at CpG sites using the Infinium HumanMethylation450 BeadChip assay at baseline and after a 6-month exercise program. We computed false discovery rates (FDR) using Sidak to account for multiplicity of tests and performed quantitative real-time polymerase chain-reaction (qRT-PCR) to confirm the effects of DNA methylations on expression levels of the top 5 genes among the aerobic participants. CpG sites identified from aerobic-exercise participants were similarly analyzed by the stretch group to quantify the effects of exercise-induced methylation changes among the group of stretch participants. RESULTS Eleven MCI participants (aerobic: 73% females; mean age 72.3 ± 6.6 years) and eight MCI participants (stretch: 75% female; mean age 70.6 ± 6.7 years) completed the training. Aerobic exercise-training was associated with increases in VO2max and with global hypo- and hypermethylation changes. The most notable finding was CpG hypomethylation within the body of the VPS52 gene (P = 5.4 × 10-26), a Golgi-associated protein, involved in intracellular protein trafficking including amyloid precursor protein. qRT-PCR confirmed a nearly twofold increased expression of VPS52. Other top findings with FDR q-value < 10-5, include hypomethylations of SCARB1 (8.8 × 10-25), ARTN (6.1 × 10-25), NR1H2 (2.1 × 10-18) and PPP2R5D (9.8 × 10-18). CONCLUSION We conclude that genome-wide DNA methylation patterns is associated with exercise training-induced methylation changes. Identification of methylation changes around genes previously shown to interact with amyloid biology, intracellular protein trafficking, and lipoprotein regulations provide further support to the likely protective effect of exercise in MCI. Future studies in larger samples are needed to confirm our findings.
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Affiliation(s)
- Julius S. Ngwa
- Division of Cardiovascular Medicine, Department of Internal Medicine, Howard University, Washington, DC, United States
| | - Evaristus Nwulia
- Department of Psychiatry and Behavioral Sciences, Howard University, Washington, DC, United States
| | - Oyonumo Ntekim
- Department of Nutritional Sciences, Howard University, Washington, DC, United States
| | - Fikru B. Bedada
- Department of Clinical Laboratory Sciences, Howard University, Washington, DC, United States
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, Howard University, Washington, DC, United States
| | - Sheeba Nadarajah
- Division of Nursing, Howard University, Washington, DC, United States,School of Nursing and Allied Health Sciences, Howard University, Washington, DC, United States,Department of Medicine, Howard University, Washington, DC, United States
| | - Steven Johnson
- Division of Geriatrics, Department of Medicine and Clinical/Translational Science Program, Howard University Hospital, Washington, DC, United States
| | - William M. Southerland
- Department of Biochemistry and Molecular Biology, Howard University, Washington, DC, United States
| | - John Kwagyan
- Georgetown-Howard U Center for Clinical and Translation Science (GHUCCTS), Howard University Hospital, Washington, DC, United States
| | - Thomas O. Obisesan
- Division of Geriatrics, Department of Medicine and Clinical/Translational Science Program, Howard University Hospital, Washington, DC, United States,*Correspondence: Thomas O. Obisesan,
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Tailor K, Paul J, Ghosh S, Kumari N, Kwabi-Addo B. RASAL2 suppresses the proliferative and invasive ability of PC3 prostate cancer cells. Oncotarget 2021; 12:2489-2499. [PMID: 34966481 PMCID: PMC8711570 DOI: 10.18632/oncotarget.28158] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 12/08/2021] [Indexed: 11/25/2022] Open
Abstract
The RAS protein activator like 2 (RASAL2) negatively regulates RAS proto-oncogene which is activated by high mutation rate in cancer. Thus, RASAL2 expression could potentially limit the function of RAS in prostate cancer (PCa). Genome-wide DNA methylation analysis demonstrated that RASAL2 is differentially hypermethylated in PCa tissues compared to benign prostate tissues. The PCR analysis of RASAL2 mRNA transcript showed differential expression in a panel of prostate cell lines with most PCa showing lower RASAL2 expression compared to benign prostatic epithelial cells. In PCa PC3 cells, the ectopic expression of RASAL2 significantly inhibited cell proliferation and invasion and induced an S phase plus G2/M phase cell cycle arrest. Ingenuity Pathway Analysis (IPA) demonstrated a cross talk between RASAL2 and TNFα, a key cytokine in immune signaling pathway that is relevant in PCa. Over-expression of RASAL2 downregulated TNFα expression whereas the knockdown of RASAL2 caused increased expression of TNFα. Taken together, our data demonstrates tumor suppressor role for RASAL2 in human PCa cells, despite increased RAS oncogenic activity. Our observation provides a new mechanistic insight of RASAL2 expression in aberrant Ras expression and immune signaling in PCa cells suggesting a potential novel therapeutic target for PCa.
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Affiliation(s)
- Krishma Tailor
- 1Department of Biochemistry and Molecular Biology, Howard University, Washington, DC 20059, USA
| | - Joseph Paul
- 1Department of Biochemistry and Molecular Biology, Howard University, Washington, DC 20059, USA
| | - Somiranjan Ghosh
- 2Department of Biology, Howard University, Washington, DC 20059, USA
| | - Namita Kumari
- 3Center for Sickle Cell Disease, Howard University, Washington, DC 20059, USA
| | - Bernard Kwabi-Addo
- 1Department of Biochemistry and Molecular Biology, Howard University, Washington, DC 20059, USA,Correspondence to:Bernard Kwabi-Addo, email:
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Saadatmand F, Gurdziel K, Jackson L, Kwabi-Addo B, Ruden DM. DNA methylation and exposure to violence among African American young adult males. Brain Behav Immun Health 2021; 14:100247. [PMID: 34589758 PMCID: PMC8474503 DOI: 10.1016/j.bbih.2021.100247] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2021] [Revised: 03/18/2021] [Accepted: 03/22/2021] [Indexed: 02/02/2023] Open
Abstract
Exposure to violence (ETV) has been linked to epigenomics mechanisms such as DNA methylation (DNAm). We used epigenetic profiling of blood collected from 32 African American young adult males who lived in Washington DC to determine if changes in DNAm at CpG sites affiliated with nervous and immune system were associated with exposure to violence. Pathway analysis of differentially methylated regions comparing high and low ETV groups revealed an enrichment of gene sets annotated to nervous system and immune ontologies. Many of these genes are known to interact with each other which suggests DNAm alters gene function in the nervous and immune system in response to ETV. Using data from a unique age group, young African American adult males, we provide evidence that lifetime ETV could impact DNA methylation in genes impacted at Central Nervous System and Immune Function sites. METHOD Methylation analysis was performed on DNA collected from the blood of participants classified with either high or low lifetime ETV. Illumina®MethylationEPIC Beadchips (~850k CpG sites) were processed on the iScan System to examine whole-genome methylation differences. Differentially methylated CpG-sites between high (n = 19) and low (n = 13) groups were identified using linear regression with violence and substance abuse as model covariates. Gene ontology analysis was used to identify enrichment categories from probes annotated to the nearest gene. RESULTS A total of 595 probes (279 hypermethylated; 316 hypomethylated) annotated to 383 genes were considered differentially methylated in association with ETV. Males with high ETV showed elevated methylation in several signaling pathways but were most impacted at Central Nervous System and Immune Function affiliated sites. Eight candidate genes were identified that play important biological roles in stress response to violence with HDAC4 (10%), NR4A3 (11%), NR4A2 (12%), DSCAML1(12%), and ELAVL3 (13%) exhibiting higher levels in the low ETV group and DLGAP1 (10%), SHANK2 (10%), and NRG1(11%) having increased methylation in the high ETV group. These findings suggest that individuals subjected to high ETV may be at risk for poor health outcomes that have not been reported previously.
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Affiliation(s)
- Forough Saadatmand
- Department of Pediatrics, College of Medicine, Howard University, Washington, DC, USA,Corresponding author.
| | - Katherine Gurdziel
- Office of the Vice President of Research, Wayne State University, Detroit, MI, USA
| | - Latifa Jackson
- Department of Pediatrics, College of Medicine, Howard University, Washington, DC, USA,W. Montague Cobb Research Laboratory, College of Arts and Sciences, Howard University, Washington, DC, USA
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, College of Medicine, Howard University, Washington, DC, USA
| | - Douglas M. Ruden
- Department of Ob/Gyn, CS Mott Center for Human Growth and Development, Wayne State University School of Medicine, Detroit, MI, USA,Institutes for Environmental Health Science, Wayne State University School of Medicine, Detroit, MI, USA
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Keith SW, Kwabi-Addo B, Zeigler-Johnson C. Interactions Between Obesity and One-Carbon Metabolism Genes in Predicting Prostate Cancer Outcomes Among White and Black Patients. J Racial Ethn Health Disparities 2021; 9:305-314. [PMID: 33432479 DOI: 10.1007/s40615-020-00958-6] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2020] [Revised: 12/26/2020] [Accepted: 12/28/2020] [Indexed: 12/31/2022]
Abstract
BACKGROUND One-carbon metabolism genes are linked to several cancers, but the association with prostate cancer (PCa) is less clear. Studies examining the relationship have not accounted for obesity, a risk factor for advanced PCa and altered methylation patterns. We hypothesized that obesity could moderate the association between one-carbon metabolism genes and PCa outcomes. METHODS We conducted secondary data analyses of the Study of Clinical Outcomes, Risk and Ethnicity. Obesity was included as a primary exposure and modifier (interacting with genetic polymorphisms) in the analytic models. We used logistic regression to determine associations of common one-carbon metabolism genotypes with odds of high stage (T3/T4) and high grade (Gleason score ≥ 7). We used Cox regression to examine associations of genotypes with biochemical recurrence. RESULTS There were 808 patients (632 White and 176 Black.) Among White men, we observed associations of TCN2_R259P with increased odds of high stage (OR = 0.64, 95% CI = 0.41-1.00), but no significant interactions with obesity. Among Black men, the SCL19A1_61bpdel and CBS_68bpINS variants were associated with high grade (OR = 2.61, 95% CI = 1.39-4.89 and OR = 0.29, 95% CI = 0.09-0.91, respectively.) Both the CBS_68bpINS and MTHFR_E429A variants interacted with obesity in Black men, where the highest risk for biochemical failure and odds of high grade, respectively, occurred among obese patients with variants. CONCLUSIONS We observed associations of one-carbon metabolism genes with different associations by race. We also observed interactions with obesity related to PCa outcomes in Black men only. Therefore, the involvement of one-carbon metabolism on PCa was dependent upon obesity status for Black men. These novel results could help identify patients that might benefit from effective weight management targeting one-carbon metabolism effects.
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Affiliation(s)
- Scott W Keith
- Division of Biostatistics, Department of Pharmacology and Experimental Therapeutics, Thomas Jefferson University, Philadelphia, PA, USA
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, Howard University, Washington, DC, USA
| | - Charnita Zeigler-Johnson
- Division of Population Science, Department of Medical Oncology, Thomas Jefferson University, Suite 314, 834 Chestnut Street, Philadelphia, PA, 19107, USA.
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Wang S, Tailor K, Kwabi-Addo B. Androgen-induced Epigenetic Profiles of Polycomb and Trithorax Genes in Prostate Cancer Cells. Anticancer Res 2020; 40:2559-2565. [PMID: 32366400 DOI: 10.21873/anticanres.14226] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2020] [Revised: 04/13/2020] [Accepted: 04/14/2020] [Indexed: 11/10/2022]
Abstract
BACKGROUND/AIM Androgens are essential for the growth of most prostate cancers (PCa). As a result, androgen ablation is the mainstay of the treatment of PCa. Proteins of the polycomb and trithorax family are master epigenetic regulators of cell type specific gene expression including androgen receptor. MATERIALS AND METHODS We interrogated epigenetic changes of a 24-gene panel corresponding to polycomb and trithorax genes by PCR array and differential gene expression by quantitative real time-PCR on prostate cancer cell line (LNCaP) treated with the synthetic ligand R1881. RESULTS We observed the highest methylation for CBX2, PCGF6, PHC2, EZH2 and TRIM27 genes and the lowest methylation for CBX8 and PCGF2 (p<0.05), and a modest decrease in the expression of EZH2. CONCLUSION Differential methylation profiles of polycomb and trithorax genes may contribute to the dynamics of prostate carcinogenesis.
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Affiliation(s)
- Songping Wang
- Department of Biochemistry and Molecular Biology, Howard University College of Medicine, Washington, DC, U.S.A
| | - Krishma Tailor
- Department of Biochemistry and Molecular Biology, Howard University College of Medicine, Washington, DC, U.S.A
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, Howard University College of Medicine, Washington, DC, U.S.A.
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Apprey V, Wang S, Tang W, Kittles RA, Southerland WM, Ittmann M, Kwabi-Addo B. Association of Genetic Ancestry With DNA Methylation Changes in Prostate Cancer Disparity. Anticancer Res 2019; 39:5861-5866. [PMID: 31704810 DOI: 10.21873/anticanres.13790] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2019] [Revised: 09/25/2019] [Accepted: 10/02/2019] [Indexed: 11/10/2022]
Abstract
BACKGROUND We hypothesized that ancestry-mediated methylated DNA changes may drive racial and ethnic disparity in prostate cancer (PCa). To test this hypothesis, we analyzed genetic ancestry and association with DNA methylation changes in PCa disparity. MATERIALS AND METHODS Pyrosequencing and ancestry informative markers were used for DNA methylation and genetic ancestry testing, respectively. RESULTS Using Spearman rho rank correlation test, the data demonstrated significant (p<0.05) and variable association between African-American ancestry and DNA methylation for all genes investigated in prostate tissues. CONCLUSION Genetic ancestry influences DNA methylation and this modifying factor must be considered in epigenetic association studies in populations of admixed patients.
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Affiliation(s)
- Victor Apprey
- Department of Family Medicine, Howard University, Washington, DC, U.S.A
| | - Songping Wang
- Department of Biochemistry and Molecular Biology Howard University, Washington, DC, U.S.A
| | - Wei Tang
- Laboratory of Human Carcinogenesis, Division of Cancer Control and Population Sciences, National Cancer Institute, National Institutes of Health, Bethesda, MD, U.S.A
| | - Rick A Kittles
- Division of Health Equities, Department of Population Sciences, City of Hope, Duarte, CA, U.S.A
| | - William M Southerland
- Department of Biochemistry and Molecular Biology Howard University, Washington, DC, U.S.A
| | - Michael Ittmann
- Department of Pathology and Immunology, Baylor College of Medicine, Houston, TX, U.S.A
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology Howard University, Washington, DC, U.S.A.
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Moses-Fynn E, Tang W, Beyene D, Apprey V, Copeland R, Kanaan Y, Kwabi-Addo B. Correlating blood-based DNA methylation markers and prostate cancer risk in African-American men. PLoS One 2018; 13:e0203322. [PMID: 30204798 PMCID: PMC6133349 DOI: 10.1371/journal.pone.0203322] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 08/17/2018] [Indexed: 12/13/2022] Open
Abstract
The objective of this work was to investigate the clinical significance of promoter gene DNA methylation changes in whole blood from African-American (AA) men with prostate cancer (PCa). We used high throughput pyrosequencing analysis to quantify percentage DNA methylation levels in a panel of 8 genes (RARβ2, TIMP3, SPARC, CDH13, HIN1, LINE1, CYB5R2 and DRD2) in blood DNA obtained from PCa and non-cancerous controls cases. Correlations of methylation status and various clinicopathological features were evaluated. Six genes tested achieved significant difference in DNA methylation levels between the PCa compared to control cases (P < 0.05). The TIMP3 loci demonstrated significant correlation of DNA methylation with age for all cases analyzed (p < 0.05). We observed an inverse correlation between CDH13 methylation (p = 0.045; r = -0.21) and serum vitamin D level whereas TIMP3 methylation (p = 0.021; r = -0.24) and DRD2 methylation (p = 0.056; r = -0.201) showed inverse correlation with supplementary vitamin D in the cancer cases. We also observed a direct correlation between methylation of RARβ2 (p = 0.0036; r = 0.293) and SPARC (p = 0.0134; r = 0.20) loci with PSA level in the controls but not the cancer cases. In addition, alcohol cases significantly correlated with higher RARβ2 methylation (p = 0.0314) in comparison with non-alcohol cases. Furthermore, we observed an inverse correlation of DRD2 methylation (p = 0.0349; r = -0.343) and Gleason score. Our data suggests that promoter methylation occurred more frequently in the blood of AA PCa and is associated with various clinicopathological features in AA men with PCa.
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Affiliation(s)
- Emmanuel Moses-Fynn
- Department of Biomedical Sciences, University of Maine, Orono, Maine, United States of America
| | - Wei Tang
- Laboratory of Human Carcinogenesis, Center for Cancer Research, National Cancer Institute (NCI), National Institutes of Health (NIH), Bethesda, Maryland, United States of America
| | - Desta Beyene
- Department of Microbiology, Howard University, Washington, D.C., United States of America
| | - Victor Apprey
- Department of Microbiology, Howard University, Washington, D.C., United States of America
| | - Robert Copeland
- Department of Pharmacology, Howard University, Washington, D.C., United States of America
| | - Yasmine Kanaan
- Department of Microbiology, Howard University, Washington, D.C., United States of America
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, Howard University, Washington, D.C., United States of America
- * E-mail:
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Kwabi-Addo B, Moses-Fynn E, Tang W, Beyene D, Apprey V, Kanaan Y. Abstract 3327: Correlating blood-based DNA methylation markers and prostate cancer risk factors in African-American men. Cancer Res 2018. [DOI: 10.1158/1538-7445.am2018-3327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Detection of prostate cancer at an early stage is key for successful treatment and improvement of outcome. However, the limitations of PSA screening are well recognized and therefore novel approaches to prostate cancer screening are necessary. We have investigated the clinical significance of DNA methylation in the blood serum of African-American men with prostate cancer.
Method: We used pyrosequencing to examine the promoter methylation for a panel of 8 genes in blood samples extracted from 91 prostate cancer cases and 91 noncancerous control cases.
Results: Seven of the 8-gene panel–RARβ2, TIMP3, SPARC, CDH13, LINE1, CYB5R2 and DRD2–tested achieved significant difference between the cancer cases when compared to control cases. The RARβ2 and TIMP3 demonstrated significant association of DNA methylation with age for all cases analyzed. Associations of methylation status and various clinicopathologic features and patient survival were evaluated: we observed significant inverse association of serum vitamin D levels in the cancer cases and DNA methylation of CDH13 and also an inverse correlation between TIMP3 and DRD2 methylation with supplementary vitamin D in the cancer cases. On the other hand, we observed a direct correlation between HIN1 methylation and serum vitamin D level. In addition, we observed a direct correlation between RARβ2 and Sparc methylation with PSA level in the control but not the cancer cases.
Conclusion: Promoter methylation occurred more frequently in the serum of patients with prostate cancer than noncancerous cases, suggesting that epigenetic markers in serum have potential for diagnosis of prostate cancer in AA men.
Citation Format: Bernard Kwabi-Addo, Emmauel Moses-Fynn, Wei Tang, Desta Beyene, Victor Apprey, Yasmine Kanaan. Correlating blood-based DNA methylation markers and prostate cancer risk factors in African-American men [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3327.
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Affiliation(s)
| | | | - Wei Tang
- 3National Institute of Health, Bethesda, MD
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Wang S, Clarke PAG, Davis R, Mumuni S, Kwabi-Addo B. Sex steroid-induced DNA methylation changes and inflammation response in prostate cancer. Cytokine 2016; 86:110-118. [PMID: 27500645 DOI: 10.1016/j.cyto.2016.07.006] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2016] [Revised: 07/08/2016] [Accepted: 07/09/2016] [Indexed: 12/31/2022]
Abstract
BACKGROUND Sex steroid hormones have been reported to induce inflammation causing dysregulation of cytokines in prostate cancer cells. However, the underlying epigenetic mechanism has not well been studied. The objective of this study was to evaluate the effect of sex steroid hormones on epigenetic DNA methylation changes in prostate cancer cells using a signature PCR methylation array panel that correspond to 96 genes with biological function in the human inflammatory and autoimmune signals in prostate cancer. Of the 96-gene panel, 32 genes showed at least 10% differentially methylation level in response to hormonal treatment when compared to untreated cells. Genes that were hypomethylated included CXCL12, CXCL5, CCL25, IL1F8, IL13RAI, STAT5A, CXCR4 and TLR5; and genes that were hypermethylated included ELA2, TOLLIP, LAG3, CD276 and MALT1. Quantitative RT-PCR analysis of select genes represented in a cytokine expression array panel showed inverse association between DNA methylation and gene expression for TOLLIP, CXCL5, CCL18 and IL5 genes and treatment of prostate cancer cells with 5'-aza-2'-deoxycytidine with or without trichostatin A induced up-regulation of TOLLIP expression. Further analysis of relative gene expression of matched prostate cancer tissues when compared to benign tissues from individual patients with prostate cancer showed increased and significant expression for CCL18 (2.6-fold; p<0.001), a modest yet significant increase in IL5 expression (1.17-fold; p=0.015), and a modest increase in CXCL5 expression (1.4-fold; p=0.25). In conclusion, our studies demonstrate that sex steroid hormones can induce aberrant gene expression via differential methylation changes in prostate carcinogenesis.
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Affiliation(s)
- Songping Wang
- Department of Biochemistry and Molecular Biology, Howard University, 2041 Georgia Ave N.W., Washington, DC 20060, USA
| | - Pamela A G Clarke
- Department of Biochemistry and Molecular Biology, Howard University, 2041 Georgia Ave N.W., Washington, DC 20060, USA
| | - Roderick Davis
- Department of Biochemistry and Molecular Biology, Howard University, 2041 Georgia Ave N.W., Washington, DC 20060, USA
| | - Salma Mumuni
- Department of Biochemistry and Molecular Biology, Howard University, 2041 Georgia Ave N.W., Washington, DC 20060, USA
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Molecular Biology, Howard University, 2041 Georgia Ave N.W., Washington, DC 20060, USA.
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Akinboye ES, Bamji ZD, Kwabi-Addo B, Ejeh D, Copeland RL, Denmeade SR, Bakare O. Design, synthesis and cytotoxicity studies of dithiocarbamate ester derivatives of emetine in prostate cancer cell lines. Bioorg Med Chem 2015; 23:5839-45. [PMID: 26187015 DOI: 10.1016/j.bmc.2015.06.072] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2015] [Revised: 06/22/2015] [Accepted: 06/30/2015] [Indexed: 11/28/2022]
Abstract
A small library of emetine dithiocarbamate ester derivatives were synthesized in 25-86% yield via derivatization of the N2'- position of emetine. Anticancer evaluation of these compounds in androgen receptor positive LNCaP and androgen receptor negative PC3 and DU145 prostate cancer cell lines revealed time dependent and dose-dependent cytotoxicity. With the exception of compound 4c, all the dithiocarbamate ester analogs in this study showed appreciable potency in all the prostate cancer cell lines (regardless of whether it is androgen receptor positive or negative) with a cytotoxicity IC50 value ranging from 1.312 ± 0.032 μM to 5.201 ± 0.125 μM by day 7 of treatment. Compared to the sodium dithiocarbamate salt 1, all the dithiocarbamate ester analogs (2 and 4a-4 g) displayed lower cytotoxicity than compound 1 (PC3, IC50 = 0.087 ± 0.005 μM; DU145, IC50 = 0.079 ± 0.003 μM and LNCaP, IC50 = 0.079 ± 0.003 μM) on day 7 of treatment. Consequently, it appears that S-alkylation of compound 1 leads to a more stable dithiocarbamate ester derivative that resulted in lower anticancer activity in the prostate cancer cell lines.
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Affiliation(s)
- Emmanuel S Akinboye
- Department of Chemistry, Howard University, 525 College St NW, Washington, DC 20059, USA; The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins School of Medicine, 1650 Orleans St, Baltimore, MD 21231, USA
| | - Zebalda D Bamji
- Department of Biochemistry and Cancer Center, Howard University, Washington, DC 20059, USA
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Cancer Center, Howard University, Washington, DC 20059, USA
| | - David Ejeh
- Archer Daniel Midland Company, James R Randall Research Center, Decatur, IL 62521, USA
| | - Robert L Copeland
- Department of Pharmacology, College of Medicine, Howard University, Adams Bldg., 520 W St NW, Washington, DC 20059, USA
| | - Samuel R Denmeade
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins School of Medicine, 1650 Orleans St, Baltimore, MD 21231, USA
| | - Oladapo Bakare
- Department of Chemistry, Howard University, 525 College St NW, Washington, DC 20059, USA.
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Devaney JM, Wang S, Furbert-Harris P, Apprey V, Ittmann M, Wang BD, Olender J, Lee NH, Kwabi-Addo B. Genome-wide differentially methylated genes in prostate cancer tissues from African-American and Caucasian men. Epigenetics 2015; 10:319-28. [PMID: 25864488 DOI: 10.1080/15592294.2015.1022019] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Increasing evidence suggests that aberrant DNA methylation changes may contribute to prostate cancer (PCa) ethnic disparity. To comprehensively identify DNA methylation alterations in PCa disparity, we used the Illumina 450K methylation platform to interrogate the methylation status of 485,577 CpG sites focusing on gene-associated regions of the human genome. Genomic DNA from African-American (AA; 7 normal and 3 cancers) and Caucasian (Cau; 8 normal and 3 cancers) was used in the analysis. Hierarchical clustering analysis identified probe-sets unique to AA and Cau samples, as well as common to both. We selected 25 promoter-associated novel CpG sites most differentially methylated by race (fold change > 1.5-fold; adjusted P < 0.05) and compared the β-value of these sites provided by the Illumina, Inc. array with quantitative methylation obtained by pyrosequencing in 7 prostate cell lines. We found very good concordance of the methylation levels between β-value and pyrosequencing. Gene expression analysis using qRT-PCR in a subset of 8 genes after treatment with 5-aza-2'-deoxycytidine and/or trichostatin showed up-regulation of gene expression in PCa cells. Quantitative analysis of 4 genes, SNRPN, SHANK2, MST1R, and ABCG5, in matched normal and PCa tissues derived from AA and Cau PCa patients demonstrated differential promoter methylation and concomitant differences in mRNA expression in prostate tissues from AA vs. Cau. Regression analysis in normal and PCa tissues as a function of race showed significantly higher methylation prevalence for SNRPN (P = 0.012), MST1R (P = 0.038), and ABCG5 (P < 0.0002) for AA vs. Cau samples. We selected the ABCG5 and SNRPN genes and verified their biological functions by Western blot analysis and siRNA gene knockout effects on cell proliferation and invasion in 4 PCa cell lines (2 AA and 2 Cau patients-derived lines). Knockdown of either ABCG5 or SNRPN resulted in a significant decrease in both invasion and proliferation in Cau PCa cell lines but we did not observe these remarkable loss-of-function effects in AA PCa cell lines. Our study demonstrates how differential genome-wide DNA methylation levels influence gene expression and biological functions in AA and Cau PCa.
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Affiliation(s)
- J M Devaney
- a Children's National Medical Center ; Center for Genetic Medicine Research ; Washington, DC USA
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Kwabi-Addo B, Wang S, Devaney J. Abstract 388: Epigenome-wide profiling identified significant differences in DNA methylation between African-American and European-American men with prostate cancer. Cancer Res 2014. [DOI: 10.1158/1538-7445.am2014-388] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: DNA methylation is a dynamic epigenetic mark that is essential for mammalian organismal development. For human prostate cancer (PCa), abundant evidence has accumulated to suggest that somatic epigenetic alterations may appear early during cancer development, as well as more commonly and consistently, than genetic changes. Several cancer-associated genes have been reported to show significant differences in DNA methylation pattern in prostate tissues from African-American (AA) and European-American men, but the genome-wide pattern and extent of these differences are largely unknown. The current study investigated genome-wide DNA methylation differences in AA and EA prostate tissue samples with the aim of assessing the variation of genome-wide patterns of DNA methylation.
Methods: To comprehensively examine the DNA methylation pattern in AA and EA samples, we used illumina 450 K methylation platform (Infunium Chip) to conduct genome-wide large scale analysis of DNA methylation changes in 7 normal and 3 PCa tissue samples from AA versus 8 normal and 3 PCa tissue samples from EA. This chip interrogates >485,000 CpG methylation sites per sample at single-nucleotide resolution and assigns each site an average beta value for quantitative methylation level.
Results: Pathway analysis of the genes with altered methylation patterns identified top canonical pathways for the involvement of cancer related network for genes involved in axonal guidance, antigen presentation, androgen signaling and protein ubiquitination pathways in prostate cancer tissues compared with normal prostate tissues obtained from AA men. On the other hand, the top canonical pathways identified in prostate cancer tissues compared with normal prostate tissues obtained from EA men are genes involved in epithelial-mesenchymal transition, p53 signaling, nucleotide sugars metabolism and germ cell-sertoli cell junction signaling pathways.
Conclusion: Using this quantitative sequencing-based approach, our work uncovers significant global DNA methylation alterations in AA versus EA prostate tissues and provides a mechanistic explanation for the disease disparity.
Citation Format: Bernard Kwabi-Addo, Songping Wang, Joseph Devaney. Epigenome-wide profiling identified significant differences in DNA methylation between African-American and European-American men with prostate cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 388. doi:10.1158/1538-7445.AM2014-388
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Devaney JM, Wang S, Funda S, Long J, Taghipour DJ, Tbaishat R, Furbert-Harris P, Ittmann M, Kwabi-Addo B. Erratum: Identification of novel DNA-methylated genes that correlate with human prostate cancer and high-grade prostatic intraepithelial neoplasia. Prostate Cancer Prostatic Dis 2014. [DOI: 10.1038/pcan.2013.58] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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Wing MR, Devaney JM, Joffe MM, Xie D, Feldman HI, Dominic EA, Guzman NJ, Ramezani A, Susztak K, Herman JG, Cope L, Harmon B, Kwabi-Addo B, Gordish-Dressman H, Go AS, He J, Lash JP, Kusek JW, Raj DS. DNA methylation profile associated with rapid decline in kidney function: findings from the CRIC study. Nephrol Dial Transplant 2014; 29:864-72. [PMID: 24516231 DOI: 10.1093/ndt/gft537] [Citation(s) in RCA: 105] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
BACKGROUND Epigenetic mechanisms may be important in the progression of chronic kidney disease (CKD). METHODS We studied the genome-wide DNA methylation pattern associated with rapid loss of kidney function using the Infinium HumanMethylation 450 K BeadChip in 40 Chronic Renal Insufficiency (CRIC) study participants (n = 3939) with the highest and lowest rates of decline in estimated glomerular filtration rate. RESULTS The mean eGFR slope was 2.2 (1.4) and -5.1 (1.2) mL/min/1.73 m(2) in the stable kidney function group and the rapid progression group, respectively. CpG islands in NPHP4, IQSEC1 and TCF3 were hypermethylated to a larger extent in subjects with stable kidney function (P-values of 7.8E-05 to 9.5E-05). These genes are involved in pathways known to promote the epithelial to mesenchymal transition and renal fibrosis. Other CKD-related genes that were differentially methylated are NOS3, NFKBIL2, CLU, NFKBIB, TGFB3 and TGFBI, which are involved in oxidative stress and inflammatory pathways (P-values of 4.5E-03 to 0.046). Pathway analysis using Ingenuity Pathway Analysis showed that gene networks related to cell signaling, carbohydrate metabolism and human behavior are epigenetically regulated in CKD. CONCLUSIONS Epigenetic modifications may be important in determining the rate of loss of kidney function in patients with established CKD.
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Affiliation(s)
- Maria R Wing
- Division of Renal Diseases and Hypertension, The George Washington University School of Medicine, Washington, DC, USA
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Devaney JM, Wang S, Funda S, Long J, Taghipour DJ, Tbaishat R, Furbert-Harris P, Ittmann M, Kwabi-Addo B. Identification of novel DNA-methylated genes that correlate with human prostate cancer and high-grade prostatic intraepithelial neoplasia. Prostate Cancer Prostatic Dis 2013; 16:292-300. [PMID: 23896626 DOI: 10.1038/pcan.2013.21] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2013] [Revised: 06/24/2013] [Accepted: 06/27/2013] [Indexed: 02/06/2023]
Abstract
BACKGROUND Prostate cancer (PCa) harbors a myriad of genomic and epigenetic defects. Cytosine methylation of CpG-rich promoter DNA is an important mechanism of epigenetic gene inactivation in PCa. There is considerable amount of data to suggest that DNA methylation-based biomarkers may be useful for the early detection and diagnosis of PCa. In addition, candidate gene-based studies have shown an association between specific gene methylation and alterations and clinicopathologic indicators of poor prognosis in PCa. METHODS To more comprehensively identify DNA methylation alterations in PCa initiation and progression, we examined the methylation status of 485 577 CpG sites from regions with a broad spectrum of CpG densities, interrogating both gene-associated and non-associated regions using the recently developed Illumina 450K methylation platform. RESULTS In all, we selected 33 promoter-associated novel CpG sites that were differentially methylated in high-grade prostatic intraepithelial neoplasia and PCa in comparison with benign prostate tissue samples (false discovery rate-adjusted P-value <0.05; β-value 0.2; fold change >1.5). Of the 33 genes, hierarchical clustering analysis demonstrated BNC1, FZD1, RPL39L, SYN2, LMX1B, CXXC5, ZNF783 and CYB5R2 as top candidate novel genes that are frequently methylated and whose methylation was associated with inactivation of gene expression in PCa cell lines. Pathway analysis of the genes with altered methylation patterns identified the involvement of a cancer-related network of genes whose activity may be regulated by TP53, MYC, TNF, IL1 and 6, IFN-γ and FOS in prostate pathogenesis. CONCLUSION Our genome-wide methylation profile shows epigenetic dysregulation of important regulatory signals in prostate carcinogenesis.
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Affiliation(s)
- J M Devaney
- Children's National Medical Center, Center for Genetic Medicine Research, Washington, DC, USA
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Tbaishat R, Wang S, Kwabi-Addo B. Abstract 1985: ZNF783, a novel zinc finger protein has tumor suppressor function in prostate cancer. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-1985] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
In the last decade hypermethylation of promoter regions has been accepted to be a prominent feature of human tumorigenesis by silencing tumor suppressor genes and other genes involved in cellular pathways. To study more in depth the involvement of aberrant methylation in prostate cancer tumorigenesis, we used a genome wide methylation array from
Illumina (Infunium) to identify novel hypermethylated genes that might contribute to prostate cancer progression. ZNF783 is one such candidate gene. ZNF783 is
Zinc-finger transcription factor that maps to human chromosome 7q33, a region implicated in prostate cancer tumorigenesis. We have observed significant hypermethylation of ZNF783 promoter CpG island in prostate cancer cell lines and prostate tumors when compared to match normal prostate tissue samples from radical prostatectomy patients. The treatment of prostate cancer cell lines with pharmacological demethylating agents restored ZNF783 gene expression indicating
a role for epigenetic DNA methylation in regulating ZNF783 expression in prostate cancer. The ZNF family of proteins has been identified to play essential roles in gene expression/regulation including inhibition of cell cycle proliferation, differentiation and apoptosis. The current study demonstrates a potential tumor suppressor role for ZNF783 in prostate cancer cells.
Citation Format: Rana Tbaishat, Songping Wang, Bernard Kwabi-Addo. ZNF783, a novel zinc finger protein has tumor suppressor function in prostate cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1985. doi:10.1158/1538-7445.AM2013-1985
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Kwabi-Addo B, Wang S, Furbert-Harris P, Yegnasubramanian S, Devaney J. Abstract 1974: Functional characterization of Basonuclin 1 (BNC1): a novel tumor suppressor gene commonly downregulated in human prostate cancer. Cancer Res 2013. [DOI: 10.1158/1538-7445.am2013-1974] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Prostate cancer (PCa) harbors a myriad of aberrant genomic and epigenetic alterations. Epigenetic inactivation of genes in PCa is largely based on transcriptional silencing by aberrant CpG methylation of CpG rich promoter regions. To better understand the role of aberrant methylation changes and to identify biological pathways likely to be affected in PCa, we used a genome-wide methylation array from Illumina (Infunium) to identify novel methylated genes associated to PCa. We identified several candidate genes including BNC1 as novel genes which are frequently methylated and whose methylation closely related to inactivation of gene expression in prostate cancer cell lines. Basonuclin1 is a zinc finger transcription factor that interacts with a subset of promoters of genes transcribed by both RNA polymerase-I and -II and has roles in maintaining ribosomal biogenesis and the proliferative potential of immature epithelial cells. We found that the expression of BNC1 negatively correlated with the degree of methylation at the CpG island in prostate tumor samples compared to benign prostate tissues. The forced-expression of BNC1 significantly decreased prostate cancer cell proliferation whereas the siRNA mediated BNC1 knock-down increased prostate cancer cell proliferation. Overall, our data suggest a potential tumor suppressor role for BNC1 that includes regulation of cell proliferation and cell-cell interaction in prostate carcinogenesis.
Citation Format: Bernard Kwabi-Addo, Songping Wang, Paulett Furbert-Harris, Srinivasan Yegnasubramanian, Joseph Devaney. Functional characterization of Basonuclin 1 (BNC1): a novel tumor suppressor gene commonly downregulated in human prostate cancer. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 1974. doi:10.1158/1538-7445.AM2013-1974
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Akinboye ES, Rosen MD, Denmeade SR, Kwabi-Addo B, Bakare O. Design, synthesis, and evaluation of pH-dependent hydrolyzable emetine analogues as treatment for prostate cancer. J Med Chem 2012; 55:7450-9. [PMID: 22867001 PMCID: PMC3654864 DOI: 10.1021/jm300426q] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
The N-2' position of the natural product emetine has been derivatized to thiourea, urea, sulfonamide, dithiocarbamate, carbamate, and pH responsive hydrolyzable amide analogues. In vitro studies of these analogues in PC3 and LNCaP prostate cancer cell lines showed that the analogues are generally less cytotoxic (average IC(50) ranging from 0.079 to 10 μM) than emetine (IC(50) ranging from 0.0237 to 0.0329 μM). The pH sensitive sodium dithiocarbamate salt 13 and the amide analogues 21, 22, 26 (obtained from maleic and citraconic anhydrides) showed the most promise as acid-activatable prodrugs under mildly acidic conditions found in the cancer microenvironment. These prodrugs released 12-83% of emetine at pH 6.5 and 41-95% emetine at pH 5.5. Compounds 13 and 26 were further shown to exhibit increased cytotoxicity in PC3 cell culture medium that was already below pH 7.0 at the time of treatment.
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Affiliation(s)
- Emmanuel S. Akinboye
- Department of Chemistry, Howard University, 525 College Street NW, Washington DC, 20059, USA
| | - Marc D. Rosen
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University School of Medicine, Baltimore, MD, 21239, USA
| | - Samuel R. Denmeade
- The Sidney Kimmel Comprehensive Cancer Center at Johns Hopkins, The Johns Hopkins University School of Medicine, Baltimore, MD, 21239, USA
| | - Bernard Kwabi-Addo
- Department of Biochemistry and Cancer Center, Howard University, Washington DC 20059
| | - Oladapo Bakare
- Department of Chemistry, Howard University, 525 College Street NW, Washington DC, 20059, USA
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Kwabi-Addo B, Wang S, Lee NH, Ittmann M, Suer F, Devaney J. Abstract 4999: Genome-wide methylation array of human prostate tissues using illumina infunium 450K bead chip reveals distinct DNA methylation signatures with potential as clinical predictors. Cancer Res 2012. [DOI: 10.1158/1538-7445.am2012-4999] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Prostate cancer (PCa) harbors a myriad of aberrant genomic and epigenetic alterations. Epigenetic inactivation of genes in PCa is largely based on transcriptional silencing by aberrant CpG methylation of CpG rich promoter regions. Candidate gene-based studies have identified a handful of aberrant CpG DNA methylation events in PCa. To better understand the role of aberrant epigenetic alterations and identify biological pathways likely to be affected by methylation mediated alterations in gene expression in PCa, we have examined the methylation status of 450,000 (450K) cytosine microarray (illumina). The 450K microarray includes CpG islands/shores/shelves/open sea, non-coding RNA and sites surrounding the transcription start sites for coding genes, but also for the corresponding gene bodies and the 3′-UTR. We demonstrate that the 450k DNA methylation array can significantly detect CpG methylation changes in radical prostatectomy prostate tissue samples. Cluster analysis revealed distinct DNA methylation profiles for prostate cancer tissues in comparison with non-malignant tissues. A total of 225 CpG loci (p > 0.00049) showed differential methylation in the cancer tissues in comparison with non-malignant tissues. Each of the 225 CpG locus was validated in silico using an independent, publicly available methylome dataset from the Cancer Genome Atlas. The majority of these loci were informative particularly in the prostate cancer. Overall, cluster analysis showed gene set enriched in pathways including transcriptional modifications, apoptosis/autophagy, chromatin assembly, growth factor signaling, cell cycle regulation and oxidative-redox reaction. This study shows that CpG locus methylation arrays could reveal important biological differences in the epigenome between prostate cancer and non-malignant tissues and provide potential markers for disease detection and/or progression.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4999. doi:1538-7445.AM2012-4999
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Affiliation(s)
| | | | - Norman H. Lee
- 2The George Washington University Medical Center, Washington, DC
| | | | - Funda Suer
- 4George Washington University School of Medicine and Health Sciences, Washington, DC
| | - Joseph Devaney
- 4George Washington University School of Medicine and Health Sciences, Washington, DC
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Vaughn MP, Biswal Shinohara D, Castagna N, Hicks JL, Netto G, De Marzo AM, Speed TJ, Reichert ZR, Kwabi-Addo B, Henderson CJ, Wolf CR, Yegnasubramanian S, Nelson WG. Humanizing π-class glutathione S-transferase regulation in a mouse model alters liver toxicity in response to acetaminophen overdose. PLoS One 2011; 6:e25707. [PMID: 22022436 PMCID: PMC3191143 DOI: 10.1371/journal.pone.0025707] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/22/2011] [Accepted: 09/08/2011] [Indexed: 12/31/2022] Open
Abstract
Background Glutathione S-transferases (GSTs) metabolize drugs and xenobiotics. Yet despite high protein sequence homology, expression of π-class GSTs, the most abundant of the enzymes, varies significantly between species. In mouse liver, hepatocytes exhibit high mGstp expression, while in human liver, hepatocytes contain little or no hGSTP1 mRNA or hGSTP1 protein. π-class GSTs are known to be critical determinants of liver responses to drugs and toxins: when treated with high doses of acetaminophen, mGstp1/2+/+ mice suffer marked liver damage, while mGstp1/2−/− mice escape liver injury. Methodology/Principal Findings To more faithfully model the contribution of π-class GSTs to human liver toxicology, we introduced hGSTP1, with its exons, introns, and flanking sequences, into the germline of mice carrying disrupted mGstp genes. In the resultant hGSTP1+mGstp1/2−/− strain, π-class GSTs were regulated differently than in wild-type mice. In the liver, enzyme expression was restricted to bile duct cells, Kupffer cells, macrophages, and endothelial cells, reminiscent of human liver, while in the prostate, enzyme production was limited to basal epithelial cells, reminiscent of human prostate. The human patterns of hGSTP1 transgene regulation were accompanied by human patterns of DNA methylation, with bisulfite genomic sequencing revealing establishment of an unmethylated CpG island sequence encompassing the gene promoter. Unlike wild-type or mGstp1/2−/− mice, when hGSTP1+mGstp1/2−/− mice were overdosed with acetaminophen, liver tissues showed limited centrilobular necrosis, suggesting that π-class GSTs may be critical determinants of toxin-induced hepatocyte injury even when not expressed by hepatocytes. Conclusions By recapitulating human π-class GST expression, hGSTP1+mGstp1/2−/− mice may better model human drug and xenobiotic toxicology.
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Affiliation(s)
- Matthew P. Vaughn
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Debika Biswal Shinohara
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
- Department of Environmental Health Sciences, Bloomberg School of Public Health, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Nicole Castagna
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Jessica L. Hicks
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - George Netto
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Angelo M. De Marzo
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Traci J. Speed
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Zachery R. Reichert
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
| | - Bernard Kwabi-Addo
- Howard University Cancer Center, Howard University, Washington, District of Columbia, United States of America
| | - Colin J. Henderson
- Cancer Research United Kingdom Molecular Pharmacology Unit, Biomedical Research Institute, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - C. Roland Wolf
- Cancer Research United Kingdom Molecular Pharmacology Unit, Biomedical Research Institute, Ninewells Hospital and Medical School, Dundee, United Kingdom
| | - Srinivasan Yegnasubramanian
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail: (SY); (WN)
| | - William G. Nelson
- Sidney Kimmel Comprehensive Cancer Center, Johns Hopkins University, Baltimore, Maryland, United States of America
- * E-mail: (SY); (WN)
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Devaney JM, Suer F, Kwabi-Addo B. Abstract ED03-03: Tools for analysis of genome-wide methylation data: An application to prostate cancer. Cancer Epidemiol Biomarkers Prev 2011. [DOI: 10.1158/1055-9965.disp-11-ed03-03] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
One of the major obstacles to effect treatment of cancer is tumor heterogeneity. Identification of markers that dictate avenues of treatment would be powerful tools in the fight against cancer. One potential marker that could be used is epigenetics. New analysis methods for epigenetic include genome-wide chips covering over 450,000 methylation sites located throughout the genome. This talk will focus on different methods of analysis for genome-wide methylation data from prostate cancer, and samples from healthy prostate samples. In addition, integration of methylation data with genetic data and additional molecular data (RNA profiling) will be discussed.
Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):ED03-03.
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Affiliation(s)
| | - Funda Suer
- 1Children's National Medical Center, Washington, DC,
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Kwabi-Addo B. Abstract ED03-01: Validation and quantitation of DNA methylation changes. Cancer Epidemiol Biomarkers Prev 2011. [DOI: 10.1158/1055-9965.disp-11-ed03-01] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
Advances in the molecular mechanisms underlying prostate cancer demonstrates that prostate cancer cells carry a myriad of genomic defects including both genetic and epigenetic alterations such as DNA methylation. Underlying this aberrant DNA methylation is the accumulating body of data hinting that normal prostate cells may be subjected to a relentless barrage of genome-damaging stresses due to both exogenous and endogenous carcinogens, with damage accumulating over time and age. There are increasing numbers of genes that show aberrant DNA methylation changes in human prostate cancer. In addition, recent reports indicate widespread methylation changes that correlate with a broad range of clinical behavior in prostate cancer patients. Thus aberrant DNA methylation changes may represent the integration of environmental or lifestyle exposures and genetic predisposition to prostate cancer. Such events may differ between individuals belonging the same ethnic group or individuals belonging to different ethnic groups. We hypothesize that differential methylation patterns maybe associated with ethnicity and could potentially contribute to the incidence and mortality of prostate cancer. Our research studies validate and quantify selected regions of genes from a genome-wide methylation analysis in a large sample number from African American and Caucasian male patients with prostate cancer. Our preferred method for studying DNA methylation is pyrosequencing over other methods of methylation analysis in that it is processive and quantitative. The principle of pyrosequencing is the real-time detection of pyro-phosphate (PPi), released after each incorporation of a specific nucleotide, initiated by simple primer extension on a PCR product template. Pyrosequencing has both qualitative and quantitative applications, and is optimal for allele quantification, DNA methylation estimation, and for regions that contain multiple polymorphisms (SNPs, IN/DELs) adjacent or in close proximity. Using this approach, we have observed significant differences in the methylation pattern for several genes in prostate tissue samples from African American and Caucasian men. Such alterations can contribute to the biological differences underlying prostate cancer disparity.
Citation Information: Cancer Epidemiol Biomarkers Prev 2011;20(10 Suppl):ED03-01.
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Abstract
Abstract
Background: Prostate cancer (PCa) is a common malignancy and a leading cause of cancer deaths among men in the United States. Abundant evidence has accumulated to suggest that epigenetic DNA methylation changes may appear earlier during PCa development than genetic changes, as well as more commonly and consistently suggesting that DNA methylated genes can be explored as DNA-based biomarker for PCa disease detection. Recently, we have identified NKX2-5 as a novel that is hypermethylated in prostate cancer. However, there is little information about the biological significance of this gene in prostate carcinogenesis. We hypothesize that NKX2-5 is a potential tumor suppressor gene that is frequently inactivated in prostate cancer. Methods: We carried out gain-and-loss functional studies of NKX2-5 in prostate cancer cell lines and validated expression at the RNA transcript level using quantitative RT-PCR. Protein expression was analyzed by western blotting and cell cycle analysis investigated by flow cytometer. Results: Over-expression of NKX2-5 was detrimental to prostate cancer cell proliferation as evidenced by significant inhibition of prostate cancer cell proliferation in comparison to control (vector only transfection) and this was due to cell arrest in Go/G1 phase and increase apoptosis. In contract, successful knockdown of NKX2-5 by shRNA transfection increased prostate cancer cell proliferation. Western blot analysis demonstrated that NKX2-5 plays a key regulatory role in the expression of several genes including p53, PTEN, Histone H1 and the androgen receptor. Conclusion: Our observation suggests that NKX2-5, a member of the homeobox gene family of plays an important tumor suppressor activity in prostate carcinogenesis. Because this gene plays important role in several signal transduction pathways, this gene can be exploited as potential biomarker for the early detection of prostate cancer and could be an attractive target to explore for drug investigation or gene therapies of prostate cancer.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3033. doi:10.1158/1538-7445.AM2011-3033
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Kwabi-Addo B, Wang S, Yegnasubramanian S. Abstract B62: Epigenetic DNA methylation changes may underlie racial differences and susceptibility to prostate cancer. Cancer Epidemiol Biomarkers Prev 2010. [DOI: 10.1158/1055-9965.disp-10-b62] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022] Open
Abstract
Abstract
Prostate cancer (PCa) is a common malignancy and a leading cause of cancer deaths among men in the United States. African American (AA) men have both a higher incidence and significantly higher mortality rates than Caucasian (Cau) men. Abundant evidence has accumulated to suggest that epigenetic DNA methylation changes may appear earlier during PCa development than genetic changes, as well as more commonly and consistently. Most studies have emphasized DNA hypermethylation as an important mechanism for inactivation of key regulatory genes in prostate cancers. Thus methylated genes can serve as biomarkers for the detection of cancer from clinical specimens such as tissue biopsies or body fluids. We used pyrosequencing to quantitatively measure methylation status of GSTP1, AR, RAR 2, SPARC, TIMP3 and NKX2-5 in prostate tissue specimen from AA and Cau men. Statistical analysis showed significantly higher methylation in the prostate cancer tissue samples in comparison with matched normal samples. Overall, we observed significant differences (p < 0.05) in the methylation level for all genes (except GSTP1) in the AA samples in comparison to the Cau samples. Furthermore, regression analysis revealed significantly higher methylation for NKX2-5 (p = 0.008) and TIMP3 (p = 0.039) in normal prostate tissue samples from AA in comparison with Cau, and a statistically significant association of methylation with age for NKX2-5 (p = 0.03) in AA in comparison with Cau. In conclusion, we observed higher prevalence of DNA methylation changes in prostate tissue samples from AA in comparison to Cau men. The DNA methylation differences in AA in comparison to Cau men may potentially contribute to racial disparity associated with prostate cancer. Gene specific DNA methylation changes could potentially lead to the identification of “ethnic sensitive” biomarker for PCa detection.
Citation Information: Cancer Epidemiol Biomarkers Prev 2010;19(10 Suppl):B62.
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Kwabi-Addo B, Wang S, Chung W, Jelinek J, Patierno SR, Wang BD, Andrawis R, Lee NH, Apprey V, Issa JP, Ittmann M. Identification of differentially methylated genes in normal prostate tissues from African American and Caucasian men. Clin Cancer Res 2010; 16:3539-47. [PMID: 20606036 DOI: 10.1158/1078-0432.ccr-09-3342] [Citation(s) in RCA: 96] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
PURPOSE Aberrant DNA methylation changes are common somatic alterations in prostate carcinogenesis. We examined the methylation status of six genes in prostate tissue specimens from African American (AA) and Caucasian (Cau) males. EXPERIMENTAL DESIGN We used pyrosequencing to quantitatively measure the methylation status of GSTP1, AR, RARbeta2, SPARC, TIMP3, and NKX2-5. Real-time PCR was used to determine gene expression, and gene reactivation was analyzed by 5-aza-2'-deoxycytidine and/or trichostatin A treatment. RESULTS Statistical analysis showed significantly higher methylation in the prostate cancer tissue samples in comparison with matched normal samples for GSTP1 (P = 0.0001 for AA; P = 0.0008 for Cau), RARbeta2 (P < 0.001 for AA and Cau), SPARC (P < 0.0001 for AA and Cau), TIMP3 (P < 0.0001 for AA and Cau), and NKX2-5 (P < 0.0001 for AA; P = 0.003 for Cau). Overall, we observed significant differences (P < 0.05) in the methylation level for all genes, except GSTP1, in the AA samples in comparison with the Cau samples. Furthermore, regression analysis revealed significantly higher methylation for NKX2-5 (P = 0.008) and TIMP3 (P = 0.039) in normal prostate tissue samples from AA in comparison with Cau, and a statistically significant association of methylation with age for NKX2-5 (P = 0.03) after adjusting for race. CONCLUSION Our findings show higher methylation of several genes in prostate tissue samples from AA in comparison with Cau and may potentially contribute to the racial differences that are observed in prostate cancer pathogenesis.
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Affiliation(s)
- Bernard Kwabi-Addo
- Department of Medicine, Cancer Center, Howard University College of Medicine, Washington, District of Columbia 20060, USA.
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Kwabi-Addo B, Wang S, Lee NH, Estecio MR, Jelinek J, Chung W, Ittmann MM. Abstract 167: Identification of differentially methylated genes in normal prostate tissues from African American and Caucasian men. Cancer Res 2010. [DOI: 10.1158/1538-7445.am10-167] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
BACKGROUND. Prostate cancer (PCa) is a common malignancy and a leading cause of cancer deaths among men in the United States. African American men have both a higher incidence and significantly higher mortality rates than Caucasian men. Abundant evidence has accumulated to suggest that epigenetic DNA methylation changes may appear earlier during PCa development than genetic changes, as well as more commonly and consistently. Most studies have emphasized DNA hypermethylation as an important mechanism for inactivation of key regulatory genes in prostate cancers. Thus methylated genes can serve as biomarkers for the detection of cancer from clinical specimens such as tissue biopsies or body fluids. However, very few studies have investigated differences in DNA methylation pattern in different ethnic groups or their application as ethnic sensitive biomarkers for disease detection. We hypothesize that differential methylation patterns maybe associated with ethnicity and could potentially contribute to the incidence and mortality of prostate cancer. METHODS. We have identified several genes to be differentially methylated in human prostate cancer cell line using methylated CpG island amplification coupled with CpG promoter microarray. Pyrosequencing was used to quantitatively measure the methylation levels of CDH11, FOXN4, PAX9, TIMP3, RPRM, SPARC, TCF3,CYP27B1, RARβ2, AR, GSTP1, NKX2-5, RASSF1A and TIMP3 genes in prostate cell lines, matched pairs of benign and prostate cancer tissues from individual prostate cancer patients, and normal prostate biopsies from African American and Caucasian men. Real time PCR was used to determine gene expression at the RNA transcript level. RESULTS. DNA hypermethylation was observed for NKX2-5, FOXN4, TIMP3, RPRM, TCF, SPARC, GSTP1, RASSF1A, RARβ2 and SPARC in prostate cancer cells and prostate cancer tissues samples. Higher frequency of methylation was observed for several genes including NKX2-5, GSTP1, RASSF1A, and RARβ2 genes in punch biopsies of normal prostate samples obtained from African American men in comparison to samples from Caucasian men. CONCLUSION. Our observations suggest a genome wide differential methylation patterns in prostate tissue samples obtained from African American men versus Caucasian men. Such alterations could account for some of the biological differences underlying prostate cancer disparity.
Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 167.
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Affiliation(s)
| | | | | | | | | | - Woonbok Chung
- 3University of Texas M.D. Anderson Cancer Ctr, Houston, TX
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Kondo Y, Shen L, Cheng AS, Ahmed S, Boumber Y, Charo C, Yamochi T, Urano T, Furukawa K, Kwabi-Addo B, Gold DL, Sekido Y, Huang THM, Issa JPJ. Gene silencing in cancer by histone H3 lysine 27 trimethylation independent of promoter DNA methylation. Nat Genet 2008; 40:741-50. [PMID: 18488029 DOI: 10.1038/ng.159] [Citation(s) in RCA: 466] [Impact Index Per Article: 29.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2007] [Accepted: 03/19/2008] [Indexed: 12/16/2022]
Abstract
Epigenetic silencing in cancer cells is mediated by at least two distinct histone modifications, polycomb-based histone H3 lysine 27 trimethylation (H3K27triM) and H3K9 dimethylation. The relationship between DNA hypermethylation and these histone modifications is not completely understood. Using chromatin immunoprecipitation microarrays (ChIP-chip) in prostate cancer cells compared to normal prostate, we found that up to 5% of promoters (16% CpG islands and 84% non-CpG islands) were enriched with H3K27triM. These genes were silenced specifically in prostate cancer, and those CpG islands affected showed low levels of DNA methylation. Downregulation of the EZH2 histone methyltransferase restored expression of the H3K27triM target genes alone or in synergy with histone deacetylase inhibition, without affecting promoter DNA methylation, and with no effect on the expression of genes silenced by DNA hypermethylation. These data establish EZH2-mediated H3K27triM as a mechanism of tumor-suppressor gene silencing in cancer that is potentially independent of promoter DNA methylation.
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Affiliation(s)
- Yutaka Kondo
- Department of Leukemia, University of Texas M. D. Anderson Cancer Center, 1515 Holcombe Boulevard, Houston, Texas 77030, USA
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Abstract
PURPOSE Prostate cancer is a leading cause of cancer death among the aging male population but the mechanism underlying this association is unclear. Aberrant methylation of promoter CpG islands is associated with silencing of genes and age-dependent methylation of several genes has been proposed as a risk factor for sporadic cancer. We examined the extent of gene methylation in pathologically normal human prostate as a function of age. EXPERIMENTAL DESIGN We used pyrosequencing to quantitatively analyze the methylation status of nine CpG islands in normal prostate tissue DNA from 45 organ donors and 45 patients who had undergone cystoprostatectomy for bladder cancer. We also analyzed 12 pairs of matched benign and prostate cancer tissue DNA from patients with prostate cancer. RESULTS Linear regression analysis revealed a significant increase in promoter methylation levels correlating with age for CpG islands at RARbeta2 (r = 0.4; P < 0.0001), RASSF1A (r = 0.27; P = 0.01), GSTP1 (r = 0.59; P < 0.0001), NKX2-5 (r = 0.27; P = 0.008), and ESR1 (r = 0.244; P = 0.023) in the normal prostate tissue samples studied. A calculated average methylation (z score) at all nine CpG loci analyzed in the normal prostate tissues showed a strong correlation with age (r = 0.6; P < 0.001). Comparison of the methylation level for the matched benign and prostate cancer tissues from individual patients with prostate cancer showed significantly higher methylation in the prostate cancer tissue samples for RARbeta2 (P < 0.001), RASSF1A (P = 0.005), GSTP1 (P < 0.001), NKX2-5 (P = 0.003), ESR1 (P = 0.016), and CLSTN1 (P = 0.01). CONCLUSIONS Our findings show aberrant hypermethylation as a function of age in the normal prostate tissues. Such age-related methylation may precede and predispose to full-blown malignancy.
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Affiliation(s)
- Bernard Kwabi-Addo
- Department of Pathology, Baylor College of Medicine, The University of Texas M. D. Anderson Cancer Center, Houston, Texas, USA.
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Abstract
PURPOSE To understand the role of relaxin peptide in prostate cancer, we analyzed the expression of relaxin and its receptor in human prostate cancer samples, the effects of relaxin signaling on cancer cell phenotype in vitro, and the effects of increased serum relaxin concentrations on cancer progression in vivo. EXPERIMENTAL DESIGN The relaxin and its receptor leucine-rich repeat containing G protein-coupled receptor 7 (LGR7) expression were studied by quantitative reverse transcription-PCR (11 benign and 44 cancer tissue samples) and by relaxin immunohistochemistry using tissue microarrays containing 10 normal and 69 cancer samples. The effects of relaxin treatment and endogenous relaxin/LGR7 suppression via short interfering RNA in PC-3 and LNCaP cells were analyzed in vitro. The effect of transgenic relaxin overexpression [Tg(Rln1)] on cancer growth and survival was evaluated in autochthonous transgenic adenocarcinoma of the mouse prostate (TRAMP). RESULTS The relaxin mRNA expression was significantly higher in recurrent prostate cancer samples. In tissue microarrays of the 10 normal tissues, 8 had low staining in epithelial cells, whereas only 1 of 9 high-grade prostatic intraepithelial neoplasia lesions had low expression (P = 0.005) and only 29 of 65 cancers had low expression (P = 0.047). Stimulation with relaxin increased cell proliferation, invasiveness, and adhesion in vitro. The suppression of relaxin/LGR7 via short interfering RNAs decreased cell invasiveness by 90% to 95% and growth by 10% to 25% and increased cell apoptosis 0.6 to 2.2 times. The Tg(Rln1) TRAMP males had shorter median survival time, associated with the decreased apoptosis of tumor cells, compared with non-Tg(Rln1) TRAMP animals. CONCLUSIONS Relaxin signaling plays a role in prostate cancer progression.
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Affiliation(s)
- Shu Feng
- Department of Obstetrics and Gynecology, Molecular and Cellular Biology, and Pathology, Baylor College of Medicine, Houston, TX 77030, USA
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Abstract
PURPOSE Alterations of fibroblast growth factors (FGFs) and their receptors contribute to prostate cancer progression by enhancing cellular proliferation, survival, and motility. The Sprouty gene family negatively regulates FGF signaling and may limit the ability of FGFs to enhance tumor progression. Sprouty1 is down regulated in human prostate cancers and Sprouty1 expression can markedly inhibit prostate cancer proliferation in vitro. Sprouty4 has been shown to negatively regulate both proliferation and cell migration in other systems. We therefore examined whether Sprouty4 expression was altered in prostate cancer. EXPERIMENTAL DESIGN Expression of Sprouty4 was examined by in situ hybridization and quantitative RT-PCR. Methylation of the Sprouty4 gene promoter was assessed using bisulfite modification and sequencing. The effect of Sprouty4 expression on cell migration was determined using an in vitro wounding assay. RESULTS By in situ hybridization Sprouty4 is expressed in normal prostatic epithelial cells and is decreased in a subset of prostate cancers. Quantitative RT-PCR confirms that Sprouty4 expression is decreased in approximately one half of prostate cancers. Analysis of the 5'-regulatory region revealed a CpG island approximately 1 kb upstream of the transcription initiation site, the proximal portion of which was preferentially methylated in prostate cancer tissues. More than one half of all prostate cancer DNAs were methylated in this region and methylation was significantly correlated with decreased Sprouty4 expression as determined by quantitative RT-PCR. When overexpressed in prostate cancer cell lines, Sprouty4 did not inhibit cell proliferation but did inhibit cell migration. CONCLUSIONS Sprouty4 expression is down regulated in human prostate cancer by DNA methylation and this decreased expression may contribute to increased cell migration.
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Affiliation(s)
- Jianghua Wang
- Department of Pathology, Baylor College of Medicine and Michael E. DeBakey, Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA
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Rosa AL, Wu YQ, Kwabi-Addo B, Coveler KJ, Reid Sutton V, Shaffer LG. Allele-specific methylation of a functional CTCF binding site upstream of MEG3 in the human imprinted domain of 14q32. Chromosome Res 2005; 13:809-18. [PMID: 16331412 DOI: 10.1007/s10577-005-1015-4] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2005] [Revised: 10/28/2005] [Indexed: 10/25/2022]
Abstract
The gene MEG3 is located in the imprinted human chromosomal region on 14q32. Imprinting of a structurally homologous region IGF2/H19 on 11p15 is mediated through cytosine methylation-controlled binding of the protein CTCF to target sites upstream of H19. We identified five new CTCF binding sites around the promoter of MEG3. Using an electrophoretic mobility shift assay, we showed that these sites bind CTCF in vitro. Using one of these sites, chromatin immunoprecipitation (ChIP) analysis confirmed CTCF binding in-vivo, and differential allele-specific methylation was demonstrated in seven individuals with either maternal or paternal uniparental disomy 14 (UPD14). The site was unmethylated on the maternally inherited chromosomes 14 and methylated on the paternally inherited chromosomes 14, suggesting parent-specific methylation of sequences upstream of MEG3. We speculate that this CTCF-binding region may provide a mechanism for the transcriptional regulation of MEG3 and DLK1.
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Affiliation(s)
- Alberto L Rosa
- Health Research and Education Center, Washington State University, Spokane, WA 99210-1495, USA
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Abstract
Prostate cancer is the most common malignancy in men in the USA and the second leading cause of cancer deaths. Fibroblast growth factors (FGFs), including FGF1 (acidic FGF), FGF2 (basic FGF), FGF6 and FGF8 are all expressed at increased levels in prostate cancer as paracrine and/or autocrine growth factors for the prostate cancer cells. In addition, increased mobilization of FGFs from the extracellular matrix in cancer tissues can increase the availability of FGFs to cancer cells. Prostate cancer epithelial cells express all four types of FGF receptors (FGFR-1 to -4) at variable frequencies. Expression of FGFR-1 and FGFR-4 is most closely linked to prostate cancer progression, while the role of FGFR-2 remains controversial. Activation of FGF receptors can activate multiple signal transduction pathways including the phospholipase Cgamma, phosphatidyl inositol 3-kinase, mitogen-activated protein kinase and signal transducers and activators of transcription (STAT) pathways, all of which play a role in prostate cancer progression. Sprouty proteins can negatively regulate FGF signal transduction, potentially limiting the impact of FGF signaling in prostate cancer, but in a significant fraction of prostate cancers there is decreased expression of Sprouty1 mRNA and protein. The effects of increased FGF receptor signaling are wide ranging and involve both the cancer cells and surrounding stroma, including the vasculature. The net result of increased FGF signaling includes enhanced proliferation, resistance to cell death, increased motility and invasiveness, increased angiogenesis, enhanced metastasis, resistance to chemotherapy and radiation and androgen independence, all of which can enhance tumor progression and clinical aggressiveness. For this reason, the FGF signaling system it is an attractive therapeutic target, particularly since therapies targeting FGF receptors and/or FGF signaling can affect both the tumor cells directly and tumor angiogenesis. A number of approaches that could target FGF receptors and/or FGF receptor signaling in prostate cancer are currently being developed.
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Affiliation(s)
- B Kwabi-Addo
- Department of Pathology, Baylor College of Medicine and Michael E DeBakey Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA.
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Kwabi-Addo B, Wang J, Erdem H, Vaid A, Castro P, Ayala G, Ittmann M. The expression of Sprouty1, an inhibitor of fibroblast growth factor signal transduction, is decreased in human prostate cancer. Cancer Res 2004; 64:4728-35. [PMID: 15256439 DOI: 10.1158/0008-5472.can-03-3759] [Citation(s) in RCA: 97] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
A considerable body of evidence indicates that alterations of fibroblast growth factors (FGFs) and their receptors contribute to prostate cancer progression. Recently, a new family of regulators of FGF activity has been identified. The Sprouty gene family negatively regulates FGF signaling in a variety of systems and could potentially limit the biological activity of FGFs in prostate cancer. Immunohistochemical analysis of normal and neoplastic prostate tissues using tissue microarrays revealed that Sprouty1 protein is down-regulated in approximately 40% of prostate cancers when compared with matched normal prostate. By quantitative real-time PCR analysis, we found that Sprouty1 mRNA levels were significantly decreased in prostate cancers in vivo in comparison with normal prostate. In prostate cancer cell lines, there is loss of the normal up-regulation of Sprouty1 mRNA and protein in response to FGFs. The decrease in Sprouty1 expression in the human prostate cancer, despite elevated levels of FGF ligands and FGF receptors, implies a loss of an important growth regulatory mechanism in prostate cancers that may potentiate the effects of increased FGF and FGF receptor expression in prostate cancer.
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Abstract
BACKGROUND Fibroblast growth factors (FGFs) are known to play an important role in the growth of prostatic epithelial cells. Benign prostatic hyperplasia (BPH) is characterized by increased epithelial and stromal proliferation within the transition zone of the prostate. FGF2, FGF7, and FGF9 are expressed in BPH tissue but expression of FGF17 has not been previously characterized in human prostate tissue. METHODS Expression of FGF17 in human prostate tissue and primary cultures of prostatic epithelial and stromal cells was determined by reverse-transcriptase polymerase chain reaction (RT-PCR). Growth response to FGF17 was assessed by addition of recombinant FGF17 to immortalized normal and neoplastic epithelial cell lines and primary cultures of prostatic stromal cells in the presence of insulin. Quantitative analysis of expression of FGF17 relative to keratin 18 and/or beta-actin in normal and hyperplastic prostate and prostate carcinoma was carried out by real-time quantitative RT-PCR. RESULTS FGF17 is expressed by prostatic epithelial cells and can act as an autocrine growth factor for immortalized and neoplastic prostatic epithelial cells. It can also promote stromal proliferation, although only at higher concentrations. Expression of FGF17 per epithelial cell was increased 2-fold in BPH. CONCLUSIONS FGF17 is expressed by normal, hyperplastic, and neoplastic prostatic epithelial cells and can promote epithelial proliferation in an autocrine manner. FGF17 expression is increased 2-fold in BPH and may contribute to the increased epithelial proliferation seen in this disease.
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Affiliation(s)
- Nathaniel Polnaszek
- Department of Pathology, Baylor College of Medicine and Houston Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA
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Polnaszek N, Kwabi-Addo B, Peterson LE, Ozen M, Greenberg NM, Ortega S, Basilico C, Ittmann M. Fibroblast growth factor 2 promotes tumor progression in an autochthonous mouse model of prostate cancer. Cancer Res 2003; 63:5754-60. [PMID: 14522896] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/27/2023]
Abstract
Fibroblast growth factor (FGF) 2 (or basic FGF) is expressed at increased levels in human prostate cancer. FGF2 can promote cell motility and proliferation, increase tumor angiogenesis, and inhibit apoptosis, all of which play an important role in tumor progression. To determine whether FGF2 plays a critical role in prostate cancer progression, we have used the transgenic adenocarcinoma of the mouse prostate (TRAMP) model system. A high percentage of TRAMP mice develop metastatic prostate cancer, and thus the TRAMP model is useful for evaluating cancer progression. TRAMP mice were crossed with FGF2 knockout (FGF2(-/-)) mice, and tumor progression in TRAMP mice that were either hemi- or homozygous for inactivation of the FGF2 allele was compared with progression in wild-type TRAMP mice. Inactivation of even one FGF2 allele resulted in increased survival, a decrease in metastasis, and inhibition of progression to the poorly differentiated phenotype in primary prostatic tumors. When compared with wild-type mice, poorly differentiated tumors arising in FGF(+/-) and FGF(-/-) mice expressed higher levels of vascular endothelial growth factor and, in some cases, increased levels of acidic FGF intracellular binding protein, a nuclear FGF1-binding protein. These findings suggest that both FGF2-mediated angiogenesis and intranuclear FGF2 activities may promote tumor progression and support the hypothesis that FGF2 plays a significant role in prostate cancer progression in vivo.
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Affiliation(s)
- Nathaniel Polnaszek
- Department of Pathology, Baylor College of Medicine and Houston Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA
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Abstract
Tumor cells are more sensitive to methionine restriction than normal tissues, a phenomenon known as methionine auxotrophy. Previous studies showed that 5-fluorouracil and methionine restriction act synergistically against a variety of tumors. The purpose of the current studies was to determine the molecular mechanism(s) underlying this synergy. 5-Fluorouracil is known to inhibit thymidylate synthase (TS), a key enzyme that transfers a methyl group from 5,10-methylene-tetrahydrofolate to dUMP during nucleotide biosynthesis. We found that methionine restriction reduced 5,10-methylene-tetrahydrofolate levels by 75% and selectively inhibited TS activity in PC-3 human prostate cancer cells within 24hr, whereas it did not in normal prostate epithelial cells. The observed fall in TS activity was accompanied by a commensurate reduction in TS protein levels as determined by western blot analysis. In contrast, 5-fluorouracil inhibited TS activity by >90% but increased TS protein levels. This increase was abrogated by methionine restriction. Surprisingly, methionine restriction increased 3H-leucine incorporation in PC-3 cells over the first 24hr, suggesting that reduction of TS levels was not simply due to global protein synthesis inhibition. Methionine restriction also significantly reduced the ratio of dUMP to dTTP in PC-3 cells, creating an imbalanced nucleotide pool. These results suggest that synergy between methionine restriction and 5-fluorouracil is attributable to multiple factors, including depletion of reduced folates, selective inhibition of TS, and creation of an imbalanced nucleotide pool. Dietary and/or enzymatic methionine restriction combined with 5-fluoruracil has great promise as a novel treatment for advanced cancer.
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Affiliation(s)
- Shan Lu
- Department of Medicine, VA Medical Center, Baylor College of Medicine, Medical Service (111H), 2002 Holcombe Blvd., Houston, TX 77030, USA
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Kwabi-Addo B, Giri D, Schmidt K, Podsypanina K, Parsons R, Greenberg N, Ittmann M. Haploinsufficiency of the Pten tumor suppressor gene promotes prostate cancer progression. Proc Natl Acad Sci U S A 2001; 98:11563-8. [PMID: 11553783 PMCID: PMC58769 DOI: 10.1073/pnas.201167798] [Citation(s) in RCA: 259] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
The PTEN gene encodes a lipid phosphatase that negatively regulates the phosphatidylinositol 3-kinase pathway and is inactivated in a wide variety of malignant neoplasms. High rates of loss of heterozygosity are observed at the 10q23.3 region containing the human PTEN gene in prostate cancer and other human malignancies, but the demonstrated rate of biallelic inactivation of the PTEN gene by mutation or homozygous deletion is significantly lower than the rate of loss of heterozygosity. The transgenic adenocarcinoma of mouse prostate model is a well characterized animal model of prostate cancer. Analysis of prostate cancer progression in transgenic adenocarcinoma of mouse prostate mice bred to Pten(+/-) heterozygous mice, coupled with analysis of the Pten gene and protein in the resulting tumors, reveals that haploinsufficiency of the Pten gene promotes the progression of prostate cancer in this model system. This observation provides a potential explanation for the discordance in rates of loss of heterozygosity at 10q23 and biallelic PTEN inactivation observed in prostate cancer and many human malignancies.
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Affiliation(s)
- B Kwabi-Addo
- Department of Pathology and Cell Biology, Baylor College of Medicine, One Baylor Plaza, Houston, TX 77030, USA
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Abstract
BACKGROUND Fibroblast growth factors (FGFs) are known to play an important role in the growth of normal prostatic epithelial cells and may promote proliferation of neoplastic prostatic epithelial cells via autocrine or paracrine mechanisms. The affinity of FGFs for FGF receptors 1-3 is critically dependent on an alternative splicing event involving the coding region for the carboxy terminal portion of the third extracellular immunoglobulin-like domain that leads to two different isoforms of each receptor (IIIb and IIIc). We therefore sought to determine whether changes in alternative splicing of FGF receptors occur in human prostate cancer. METHODS RNAs from normal prostate and clinically localized or metastatic prostate cancers were analyzed by reverse transcriptase polymerase chain reaction (RT-PCR) followed by digestion of products with restriction enzymes specific for each FGF receptor isoform and quantitation of the relative amounts of each isoform after electrophoresis. For FGFR-2, this was correlated with immunohistochemistry to determine the localization of the protein product. RESULTS FGFR-1 is expressed exclusively as the IIIc isoform in prostate cancer while FGFR-3 is expressed predominantly as the IIIb isoform, similar to the expression pattern in normal prostatic epithelial cells. In contrast, there was variable expression of the FGFR-2 IIIb and IIIc isoforms. In the majority of cases the FGFR-2 IIIb isoform was the predominant or exclusive isoform expressed, similar to normal epithelial cells, but in a subset of cases the IIIc isoform was increased, indicating a change in alternative splicing of FGFR-2 in some cases. CONCLUSIONS In most cases of prostate cancer there are no changes in alternative splicing of FGF receptors, but in a subgroup there is increased expression of the FGFR-2 IIIc isoform. Given that the affinity of FGFs is highly dependent on the isoform of FGF receptor expressed, this information is critical in understanding the effects of FGFs on prostate cancer cells in vivo.
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Affiliation(s)
- B Kwabi-Addo
- Department of Pathology, Baylor College of Medicine, Houston Department of Veterans Affairs Medical Center, 2002 Holcombe Blvd., Houston, TX 77030, USA
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Abstract
BACKGROUND Fibroblast growth factors (FGFs) are known to play an important role in the growth of normal prostatic epithelial cells. FGF-10 is a secreted growth factor that binds to FGF receptor-2 IIIb, which is expressed in prostatic epithelial cells and thus can potentially act as a growth factor for these cells. Prior work has indicated that FGF10 may play an important role in the development of the rat prostate, but its role in the adult human prostate is unclear. METHODS Expression of FGF10 in human prostate tissue and primary cultures of prostatic epithelial and stromal cells was assessed by reverse-transcriptase PCR (RT-PCR) and Northern blotting. Growth response to FGF10 was assessed by the addition of recombinant FGF-10 to primary cultures of prostatic epithelial and stromal cells. RESULTS FGF10 is expressed at levels detectable by RT-PCR and can act as a growth factor for prostatic epithelial cells, but is not active as a growth factor for stromal cells. However, FGF10 is expressed at extremely low levels relative to FGF7, which has a similar biological activity. CONCLUSIONS While FGF10 may play a role in prostatic development, it is unlikely to play a major role in prostate growth in normal or hyperplastic adult human prostate, due to its extremely low expression compared to FGF7.
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Affiliation(s)
- F Ropiquet
- Department of Pathology, Baylor College of Medicine and Houston Department of Veterans Affairs Medical Center, TX 77030, USA
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Ropiquet F, Giri D, Kwabi-Addo B, Mansukhani A, Ittmann M. Increased expression of fibroblast growth factor 6 in human prostatic intraepithelial neoplasia and prostate cancer. Cancer Res 2000; 60:4245-50. [PMID: 10945637] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/17/2023]
Abstract
Fibroblast growth factors (FGFs) are known to play an important role in the growth of normal prostatic epithelial cells. In addition to their effects on proliferation, FGFs can promote cell motility, increase tumor angiogenesis, and inhibit apoptosis, all of which play an important role in tumor progression. To determine whether FGFs are overexpressed in human prostate cancers, we analyzed 26 prostate cancer RNAs by reverse transcription-PCR for expression of FGF3, FGF4, and FGF6, which cannot be detected in normal prostate tissue by this technique. Fourteen of 26 prostate cancers expressed FGF6 mRNA. No expression of FGF3 or FGF4 was detected. An ELISA of tissue extracts of normal prostate, high-grade prostatic intraepithelial neoplasia (PIN), and prostate cancer for FGF6 showed that this growth factor was undetectable in normal prostate but was present at elevated levels in 4 of 9 PIN lesions and in 15 of 24 prostate cancers. Immunohistochemical analysis with anti-FGF6 antibody revealed weak staining of prostatic basal cells in normal prostate that was markedly elevated in PIN. In the prostate cancers, the majority of cases revealed expression of FGF6 by the prostate cancer cells themselves. In two cases, expression was present in prostatic stromal cells. Exogenous FGF6 was able to stimulate proliferation of primary prostatic epithelial and stromal cells, immortalized prostatic epithelial cells, and prostate cancer cell lines in tissue culture. FGF receptor 4, which is the most potent FGF receptor for FGF6, is expressed in the human prostate in vivo and in all of the cultured cell lines. Thus, FGF6 is increased in PIN and prostate cancer and can promote the proliferation of the transformed prostatic epithelial cells via paracrine and autocrine mechanisms.
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Affiliation(s)
- F Ropiquet
- Department of Pathology, Baylor College of Medicine and Department of Veterans Affairs Medical Center, Houston, Texas 77030, USA
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Abstract
The PTEN gene encodes a phosphatase that acts as a tumor-suppressor gene and is mutated in a variety of human cancers. Alterations of the PTEN gene in these tumor samples were identified using exon-by-exon analysis of the gene using single-stranded conformational polymorphism or direct sequencing of PTEN cDNA. However, in humans, mutational analysis of a PTEN cDNA template can produce false results because of a highly conserved PTEN processed pseudogene that shares more than 98% homology with the coding region of functional PTEN. PTEN-knockout mice develop tumors, suggesting that mouse tumor models are useful in vivo model systems to study PTEN function. Any mutational analysis of mouse PTEN cDNA may also produce false results if mice contain a highly conserved PTEN pseudogene. In this paper, we demonstrate the absence of any PTEN pseudogene in the mouse and discuss the significance of this observation for the mutational studies of the PTEN gene in mouse tumor models.
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Affiliation(s)
- B Kwabi-Addo
- Department of Pathology, Baylor College of Medicine and Houston Department of Veterans Affairs Medical Center, Texas, USA
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Smith AJ, De Sousa MA, Kwabi-Addo B, Heppell-Parton A, Impey H, Rabbitts P. A site-directed chromosomal translocation induced in embryonic stem cells by Cre-loxP recombination. Nat Genet 1995; 9:376-85. [PMID: 7795643 DOI: 10.1038/ng0495-376] [Citation(s) in RCA: 196] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
Abstract
We have developed a strategy for chromosome engineering in embryonic stem (ES) cells that relies on sequential gene targeting and Cre-loxP site-specific recombination. Gene targeting was first used to integrate loxP sites at the desired positions in the genome. Transient expression of Cre recombinase was then used to mediate the chromosomal rearrangement. A genetic selection relying on reconstruction of a selectable marker from sequences co-integrated with the loxP sites allowed detection of cells containing the Cre-mediated rearrangement. A programmed translocation between the c-myc and immunoglobulin heavy chain genes on chromosomes 15 and 12 was created by this method. This strategy will allow the design of a variety of chromosome rearrangements that can be selected and verified in ES cells or activated in ES cell-derived mice.
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Affiliation(s)
- A J Smith
- MRC Laboratory of Molecular Biology, MRC Centre, Cambridge, England, UK
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