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Marley AR, Ryder JR, Turcotte LM, Spector LG. Maternal obesity and acute lymphoblastic leukemia risk in offspring: A summary of trends, epidemiological evidence, and possible biological mechanisms. Leuk Res 2022; 121:106924. [PMID: 35939888 DOI: 10.1016/j.leukres.2022.106924] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2022] [Revised: 07/13/2022] [Accepted: 08/01/2022] [Indexed: 10/16/2022]
Abstract
Acute lymphoblastic leukemia, a heterogenous malignancy characterized by uncontrolled proliferation of lymphoid progenitors and generally initiated in utero, is the most common pediatric cancer. Although incidence of ALL has been steadily increasing in recent decades, no clear reason for this trend has been identified. Rising concurrently with ALL incidence, increasing maternal obesity rates may be partially contributing to increasing ALL prevelance. Epidemiological studies, including a recent meta-analysis, have found an association between maternal obesity and leukemogenesis in offspring, although mechanisms underlying this association remain unknown. Therefore, the purpose of this review is to propose possible mechanisms connecting maternal obesity to ALL risk in offspring, including changes to fetal/neonatal epigenetics, altered insulin-like growth factor profiles and insulin resistance, modified adipokine production and secretion, changes to immune cell populations, and impacts on birthweight and childhood obesity/adiposity. We describe how each proposed mechanism is biologically plausible due to their connection with maternal obesity, presence in neonatal and/or fetal tissue, observation in pediatric ALL patients at diagnosis, and association with leukemogenesis, A description of ALL and maternal obesity trends, a summary of epidemiological evidence, a discussion of the pathway from intrauterine environment to subsequent malignancy, and propositions for future directions are also presented.
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Affiliation(s)
- Andrew R Marley
- Division of Epidemiology and Clinical Research, Department of Pediatrics, University of Minnesota, 420 Delaware St SE MMC 715, Minneapolis, MN 55455, USA.
| | - Justin R Ryder
- Division of Epidemiology and Clinical Research, Department of Pediatrics, University of Minnesota, 420 Delaware St SE MMC 715, Minneapolis, MN 55455, USA; Center for Pediatric Obesity Medicine, Department of Pediatrics, University of Minnesota, 2450 Riverside Ave S AO-102, Minneapolis, MN 55454, USA
| | - Lucie M Turcotte
- Division of Hematology/Oncology, Department of Pediatrics, University of Minnesota, 420 Delaware St SE MMC 484, Minneapolis, MN 55455, USA; Masonic Cancer Center, University of Minnesota, 425 East River Parkway, Minneapolis, MN 55455, USA
| | - Logan G Spector
- Division of Epidemiology and Clinical Research, Department of Pediatrics, University of Minnesota, 420 Delaware St SE MMC 715, Minneapolis, MN 55455, USA; Masonic Cancer Center, University of Minnesota, 425 East River Parkway, Minneapolis, MN 55455, USA
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2
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Fang W, Xia Y. LncRNA HLA-F-AS1 attenuates the ovarian cancer development by targeting miR-21-3p/PEG3 axis. Anticancer Drugs 2022; 33:671-681. [PMID: 35276697 DOI: 10.1097/cad.0000000000001288] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Dysregulated long noncoding RNA (lncRNA) HLA-F-AS1 is depicted in numerous cancers. However, its function in ovarian cancer has yet to be clarified. LncRNA HLA-F-AS1, miR-21-3p, and PEG3 expressions in ovarian cancer tissues and cells were measured via reverse transcription quantitative PCR. Scratch and CCK8 assays were performed to evaluate the cells' migratory and proliferative abilities, respectively. To assess the expressions of the apoptosis-related proteins Bax and Bcl-2, Western blotting was conducted. Anti-AGO2 RNA immunoprecipitation (RIP) and dual-luciferase reporter assays were executed to study lncRNA HLA-F-AS1's and PEG3 3'UTR's interactions to miR-21-3p. Finally, the tumor growth in vivo was inspected by performing a xenograft experiment. Among the ovarian cancer tissues and cells, the expressions of PEG3 and lncRNA HLA-F-AS1 were depleted while an elevated miR-21-3p expression was observed. HLA-F-AS1's overexpression attenuated ovarian cancer development in vivo and in vitro . MiR-21-3p targeted PEG3 3'UTR while HLA-F-AS1 targeted miR-21-3p. HLA-F-AS1 overexpression mitigated the enhancement brought about by miR-21-3p mimic on ovarian cancer cells' proliferation and migration. Meanwhile, PEG3 overexpression abrogated miR-21-3p mimic's function as an oncogene in the progression of ovarian cancer. Ovarian cancer development is suppressed when lncRNA HLA-F-AS1 targets the miR-21-3p/PEG3 axis. This may possibly be a novel therapeutic target for ovarian cancer.
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Affiliation(s)
- Wenhong Fang
- Department of Gynecology and Obstetrics, Wuhan No.6 Hospital, Affiliated Hospital of Jianghan University, Wuhan, Hubei, China
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3
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PEG3 mutation is associated with elevated tumor mutation burden and poor prognosis in breast cancer. Biosci Rep 2021; 40:225944. [PMID: 32729618 PMCID: PMC7419805 DOI: 10.1042/bsr20201648] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2020] [Revised: 07/22/2020] [Accepted: 07/28/2020] [Indexed: 12/15/2022] Open
Abstract
Background: Breast cancer is the second most common malignancy in women and considered as a severe health burden. PEG3 mutations have been observed in several cancers. However, the associations of PEG3 mutation with tumor mutation burden (TMB) and prognosis in breast cancer have not been investigated. Methods: In our study, the somatic mutation data of 986 breast cancer patients from The Cancer Genome Atlas (TCGA) were analyzed. Results: It showed that PEG3 had a relatively high mutation rate (2%). After calculated the TMB in PEG3 mutant and PEG3 wild-type groups, we found the TMB value was significantly higher in PEG3 mutant samples than that in PEG3 wild-type samples (P = 5.6e-07), which was independent of the confounding factors including age, stage, mutations of BRCA1, BRCA2 and POLE (odd ratio, 0.45; 95% CI, 0.20–0.98; P=0.044). Survival analysis revealed that PEG3 mutant samples had inferior survival outcome compared with the PEG3 wild-type samples after adjusted for the confounding factors above (hazard ratio, 0.27; 95% CI: 0.12–0.57; P<0.001). Conclusion: These results illustrated that PEG3 mutation was associated with high TMB and inferior prognosis, suggesting PEG3 mutation might play a guiding role in prognosis prediction and immunotherapy selection in breast cancer.
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Lozano-Ureña A, Jiménez-Villalba E, Pinedo-Serrano A, Jordán-Pla A, Kirstein M, Ferrón SR. Aberrations of Genomic Imprinting in Glioblastoma Formation. Front Oncol 2021; 11:630482. [PMID: 33777782 PMCID: PMC7994891 DOI: 10.3389/fonc.2021.630482] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2020] [Accepted: 02/15/2021] [Indexed: 12/21/2022] Open
Abstract
In human glioblastoma (GBM), the presence of a small population of cells with stem cell characteristics, the glioma stem cells (GSCs), has been described. These cells have GBM potential and are responsible for the origin of the tumors. However, whether GSCs originate from normal neural stem cells (NSCs) as a consequence of genetic and epigenetic changes and/or dedifferentiation from somatic cells remains to be investigated. Genomic imprinting is an epigenetic marking process that causes genes to be expressed depending on their parental origin. The dysregulation of the imprinting pattern or the loss of genomic imprinting (LOI) have been described in different tumors including GBM, being one of the earliest and most common events that occurs in human cancers. Here we have gathered the current knowledge of the role of imprinted genes in normal NSCs function and how the imprinting process is altered in human GBM. We also review the changes at particular imprinted loci that might be involved in the development of the tumor. Understanding the mechanistic similarities in the regulation of genomic imprinting between normal NSCs and GBM cells will be helpful to identify molecular players that might be involved in the development of human GBM.
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Affiliation(s)
- Anna Lozano-Ureña
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Valencia, Spain.,Departamento de Biología Celular, Universidad de Valencia, Valencia, Spain
| | | | | | | | - Martina Kirstein
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Valencia, Spain.,Departamento de Biología Celular, Universidad de Valencia, Valencia, Spain
| | - Sacri R Ferrón
- Instituto de Biotecnología y Biomedicina (BIOTECMED), Valencia, Spain.,Departamento de Biología Celular, Universidad de Valencia, Valencia, Spain
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M2 bone marrow-derived macrophage-derived exosomes shuffle microRNA-21 to accelerate immune escape of glioma by modulating PEG3. Cancer Cell Int 2020; 20:93. [PMID: 32231463 PMCID: PMC7099792 DOI: 10.1186/s12935-020-1163-9] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/15/2020] [Accepted: 03/04/2020] [Indexed: 02/08/2023] Open
Abstract
Background Growing studies have focused on the role of microRNA-21 (miR-21) in glioma, thus our objective was to discuss the effect of M2 bone marrow-derived macrophage (BMDM)-derived exosomes (BMDM-Exos) shuffle miR-21 on biological functions of glioma cells by regulating paternally expressed gene 3 (PEG3). Methods Seventy-one cases of human glioma tissues and 30 cases of non-tumor normal brain tissues were collected and stored in liquid nitrogen. PEG3 and miR-21 expression in glioma tissues was tested. The fasting venous blood of glioma patients and healthy control was collected and centrifuged, and then the supernatant was stored at - 80 °C refrigerator. The contents of interferon (IFN)-γ and transforming growth factor-β1 (TGF-β1) in serum were tested by ELISA. Glioma cells and normal glial cells were cultured to screen the target cells for further in vitro experiments. BMDM-Exos was obtained by ultra-high speed centrifugation and then was identified. BMDM-Exos was co-cultured with U87 cells to detect the biological functions. The fasting venous blood of glioma patients was extracted and treated with ethylene diamine tetraacetic acid-K2 anti-freezing, and then CD8+T cells were isolated. CD8+T cells were co-cultured with U87 cells to detect the CD8+T proliferation, cell cytotoxic activity, U87 cell activity, as well as IFN-γ and TGF-β1 levels. Moreover, BALB/c-nu/nu mice was taken, and the human-nude mouse glioma orthotopic transplantation model was established with U87 cells, and then mice were grouped to test the trends in tumor growth. The brain of mice (fixed by 10% formaldehyde) was sliced to detect the expression of Ki67 and proliferating cell nuclear antigen (PCNA). The spleen of mice was taken to prepare single-cell suspension, and the percentage of T lymphocytes in spleen to CD8+T cells was detected. Results PEG3 expression was decreased and miR-21 expression was increased in glioma cells and tissues. Depleting miR-21 or restoring PEG3 suppressed growth, migration and invasion as well as accelerated apoptosis of glioma cells, also raised CD8+T proliferation, cell cytotoxic activity, and IFN-γ level as well as decreased U87 cell activity and TGF-β1 level. BMDM-Exos shuttle miR-21 promoted migration, proliferation and invasion as well as suppressed apoptosis of glioma cells by reducing PEG3. Exosomes enhanced the volume of tumor, Ki67 and PCNA expression, reduced the percentage of CD8+T cells in glioma mice. Conclusion BMDM-Exos shuffle miR-21 to facilitate invasion, proliferation and migration as well as inhibit apoptosis of glioma cells via inhibiting PEG3, furthermore, promoting immune escape of glioma cells.
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Huang M, Chen Y, Han D, Lei Z, Chu X. Role of the zinc finger and SCAN domain-containing transcription factors in cancer. Am J Cancer Res 2019; 9:816-836. [PMID: 31218096 PMCID: PMC6556609] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2019] [Accepted: 04/04/2019] [Indexed: 06/09/2023] Open
Abstract
Transcription factors are key determinants of gene expression that recognize and bind to short DNA sequence motifs, thereby regulating many biological processes including differentiation, development, and metabolism. Transcription factors are increasingly recognized for their roles in cancer progression. Here, we describe a subfamily of zinc finger transcription factors named zinc finger and SCAN domain containing (ZSCAN) transcription factors. In this review, we summarize the identified members of the ZSCAN family of transcription factors and their roles in cancer progression. Due to the complex regulation mechanisms, ZSCAN transcription factors may show promotive or prohibitive efforts in angiogenesis, cell apoptosis, cell differentiation, cell migration and invasion, cell proliferation, stem cell properties, and chemotherapy sensitivity. The upstream regulation mechanisms of their varied expression levels may include gene mutation, DNA methylation, alternative splicing, and miRNA regulation. What's more, to clarify their diverse functions, we summarize the modulation mechanisms of their activity in downstream genes transcription, including protein-protein interactions mediated by their SCAN box, recruitment of co-regulating molecules and post-translational modifications. A better understanding of the widespread regulatory mode of these transcription factors will provide further insight into the mechanism of transcriptional regulation and suggest novel therapeutic strategies against tumor progression.
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Affiliation(s)
- Mengxi Huang
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing UniversityNanjing, Jiangsu Province, People’s Republic of China
| | - Yanyan Chen
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing UniversityNanjing, Jiangsu Province, People’s Republic of China
| | - Dong Han
- Department of Medical Oncology, Jinling Hospital, Nanjing Clinical School of Southern Medical UniversityNanjing, Jiangsu Province, People’s Republic of China
| | - Zengjie Lei
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing UniversityNanjing, Jiangsu Province, People’s Republic of China
- Department of Medical Oncology, Jinling Hospital, Nanjing Clinical School of Southern Medical UniversityNanjing, Jiangsu Province, People’s Republic of China
| | - Xiaoyuan Chu
- Department of Medical Oncology, Jinling Hospital, School of Medicine, Nanjing UniversityNanjing, Jiangsu Province, People’s Republic of China
- Department of Medical Oncology, Jinling Hospital, Nanjing Clinical School of Southern Medical UniversityNanjing, Jiangsu Province, People’s Republic of China
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Tindula G, Murphy SK, Grenier C, Huang Z, Huen K, Escudero-Fung M, Bradman A, Eskenazi B, Hoyo C, Holland N. DNA methylation of imprinted genes in Mexican-American newborn children with prenatal phthalate exposure. Epigenomics 2018; 10:1011-1026. [PMID: 29957030 PMCID: PMC6088267 DOI: 10.2217/epi-2017-0178] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/31/2017] [Accepted: 03/28/2018] [Indexed: 02/06/2023] Open
Abstract
AIM Imprinted genes exhibit expression in a parent-of-origin-dependent manner and are critical for child development. Recent limited evidence suggests that prenatal exposure to phthalates, ubiquitous endocrine disruptors, can affect their epigenetic dysregulation. MATERIALS & METHODS We quantified DNA methylation of nine imprinted gene differentially methylated regions by pyrosequencing in 296 cord blood DNA samples in a Mexican-American cohort. Fetal exposure was estimated by phthalate metabolite concentrations in maternal urine samples during pregnancy. RESULTS Several differentially methylated regions of imprinted genes were associated with high molecular weight phthalates. The most consistent, positive, and false discovery rate significant associations were observed for MEG3. CONCLUSION Phthalate exposure in utero may affect methylation status of imprinted genes in newborn children.
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Affiliation(s)
- Gwen Tindula
- Center for Environmental Research & Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Susan K Murphy
- Epigenetics Research Laboratory, Department of Obstetrics & Gynecology, Duke University Medical Center, Durham, NC 27708, USA
| | - Carole Grenier
- Epigenetics Research Laboratory, Department of Obstetrics & Gynecology, Duke University Medical Center, Durham, NC 27708, USA
| | - Zhiqing Huang
- Epigenetics Research Laboratory, Department of Obstetrics & Gynecology, Duke University Medical Center, Durham, NC 27708, USA
| | - Karen Huen
- Center for Environmental Research & Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Maria Escudero-Fung
- Center for Environmental Research & Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Asa Bradman
- Center for Environmental Research & Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Brenda Eskenazi
- Center for Environmental Research & Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA 94720, USA
| | - Cathrine Hoyo
- Epigenetics Research Laboratory, Department of Obstetrics & Gynecology, Duke University Medical Center, Durham, NC 27708, USA
- Department of Biological Sciences, Center for Human Health & the Environment, North Carolina State University (NCSU), Raleigh, NC 27606, USA
| | - Nina Holland
- Center for Environmental Research & Children's Health (CERCH), School of Public Health, University of California, Berkeley, CA 94720, USA
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Mai Q, Mai X, Huang X, Zhang D, Huang K, Zhou C. Imprinting Status in Two Human Parthenogenetic Embryonic Stem Cell Lines: Analysis of 63 Imprinted Gene Expression Levels in Undifferentiated and Early Differentiated Stages. Stem Cells Dev 2018; 27:430-439. [PMID: 29402175 DOI: 10.1089/scd.2017.0247] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Human parthenogenetic embryonic stem cells (hPESCs) represent a source of histocompatible tissues for transplantation and carry two copies of the maternal genome, but lack the paternal genome. In this study, we selected 63 known human imprinted genes to investigate the imprinting status of hPESC. The expression level of these genes, including 27 maternally and 36 paternally imprinted were illustrated in hPESC and human embryonic stem cells (hESCs) derived from fertilized embryo lines. The expression activity changes of these genes were analyzed in undifferentiated and early differentiated hPESC lines. In addition, the methylation status of four differentially methylated regions (DMRs) of the imprinted genes was analyzed in undifferentiated and early differentiated hPESC and hESC lines. As a result, we found that all the maternally imprinted genes were expressed at similar levels in the undifferentiated hPESC lines and the hESC lines, except ZNF264 and ATP10A. Twenty-one analyzed paternal imprinted genes were expressed at the same level in two separated hPESC lines as well as compared with the hESC lines, whereas 15 other paternal imprinted genes were significantly downregulated or inactivated in hPESC lines as compared with the hESC line. During prolonged passage, the expression levels of the majority of imprinted genes remained stable in two hPESC lines. The four DMRs, including PEG3/ZIM2 (DMRs), SNURF/SNRPN DMRs, and KVDMR1 DMRs are highly methylated in the genes of two undifferentiated hPESCs and its embryonic bodies (EBs), whereas the genes of the undifferentiated hESCs and its EBs are half methylated. During the early differentiation stage, the imprinted genes showed the same expression trend and the expression levels of H19, IGF2, SLC22A2, SLC22A3/SLC22A18, and CPA4 were significantly upregulated in both hPESC lines. As conclusion, hPESCs show a substantial degree of epigenetic stability with respect to some imprinted genes.
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Affiliation(s)
- Qingyun Mai
- 1 Reproductive Medical Center, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
| | - Xiuyun Mai
- 1 Reproductive Medical Center, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China .,2 Reproductive Medical Center , Guangzhou Women and Children's Medical Center, Guangzhou, China
| | - Xin Huang
- 1 Reproductive Medical Center, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
| | - Dan Zhang
- 1 Reproductive Medical Center, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
| | - Kejun Huang
- 1 Reproductive Medical Center, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
| | - Canquan Zhou
- 1 Reproductive Medical Center, The First Affiliated Hospital of Sun Yat-sen University , Guangzhou, China
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Lozano-Ureña A, Montalbán-Loro R, Ferguson-Smith AC, Ferrón SR. Genomic Imprinting and the Regulation of Postnatal Neurogenesis. Brain Plast 2017; 3:89-98. [PMID: 29765862 PMCID: PMC5928554 DOI: 10.3233/bpl-160041] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022] Open
Abstract
Most genes required for mammalian development are expressed from both maternally and paternally inherited chromosomal homologues. However, there are a small number of genes known as “imprinted genes” that only express a single allele from one parent, which is repressed on the gene from the other parent. Imprinted genes are dependent on epigenetic mechanisms such as DNA methylation and post-translational modifications of the DNA-associated histone proteins to establish and maintain their parental identity. In the brain, multiple transcripts have been identified which show parental origin-specific expression biases. However, the mechanistic relationship with canonical imprinting is unknown. Recent studies on the postnatal neurogenic niches raise many intriguing questions concerning the role of genomic imprinting and gene dosage during postnatal neurogenesis, including how imprinted genes operate in concert with signalling cues to contribute to newborn neurons’ formation during adulthood. Here we have gathered the current knowledge on the imprinting process in the neurogenic niches. We also review the phenotypes associated with genetic mutations at particular imprinted loci in order to consider the impact of imprinted genes in the maintenance and/or differentiation of the neural stem cell pool in vivo and during brain tumour formation.
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Affiliation(s)
- Anna Lozano-Ureña
- ERI BiotecMed Departamento de Biología Celular, Universidad de Valencia, Spain
| | | | | | - Sacri R Ferrón
- ERI BiotecMed Departamento de Biología Celular, Universidad de Valencia, Spain
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Sazhenova EA, Nikitina TV, Skryabin NA, Minaycheva LI, Ivanova TV, Nemtseva TN, Yuriev SY, Evtushenko ID, Lebedev IN. Epigenetic status of imprinted genes in placenta during recurrent pregnancy loss. RUSS J GENET+ 2017. [DOI: 10.1134/s1022795417020090] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Soubry A, Hoyo C, Butt CM, Fieuws S, Price TM, Murphy SK, Stapleton HM. Human exposure to flame-retardants is associated with aberrant DNA methylation at imprinted genes in sperm. ENVIRONMENTAL EPIGENETICS 2017; 3:dvx003. [PMID: 29492305 PMCID: PMC5804543 DOI: 10.1093/eep/dvx003] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2016] [Revised: 02/15/2017] [Accepted: 02/27/2017] [Indexed: 05/18/2023]
Abstract
Emerging evidence suggests that early exposure to endocrine disrupting chemicals has long-term consequences that can influence disease risk in offspring. During gametogenesis, imprinted genes are reasonable epigenetic targets with the ability to retain and transfer environmental messages. We hypothesized that exposures to organophosphate (OP) flame-retardants can alter DNA methylation in human sperm cells affecting offspring's health. Sperm and urine samples were collected from 67 men in North Carolina, USA. Urinary metabolites of a chlorinated OP, tris(1,3-dichloro-2-propyl) phosphate, and two non-chlorinated OPs, triphenyl phosphate and mono-isopropylphenyl diphenyl phosphate, were measured using liquid-chromatography tandem mass-spectrometry. Sperm DNA methylation at multiple CpG sites of the regulatory differentially methylated regions (DMRs) of imprinted genes GRB10, H19, IGF2, MEG3, NDN, NNAT, PEG1/MEST, PEG3, PLAGL1, SNRPN, and SGCE/PEG10 was quantified using bisulfite pyrosequencing. Regression models were used to determine potential associations between OP concentrations and DNA methylation. We found that men with higher concentrations of urinary OP metabolites, known to originate from flame-retardants, have a slightly higher fraction of sperm cells that are aberrantly methylated. After adjusting for age, obesity-status and multiple testing, exposure to mono-isopropylphenyl diphenyl phosphate was significantly related to hypermethylation at the MEG3, NDN, SNRPN DMRs. Exposure to triphenyl phosphate was associated with hypermethylation at the GRB10 DMR; and tris(1,3-dichloro-2-propyl) phosphate exposure was associated with altered methylation at the MEG3 and H19 DMRs. Although measured methylation differences were small, implications for public health can be substantial. Interestingly, our data indicated that a multiplicity of OPs in the human body is associated with increased DNA methylation aberrancies in sperm, compared to exposure to few OPs. Further research is required in larger study populations to determine if our findings can be generalized.
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Affiliation(s)
- Adelheid Soubry
- Epidemiology Research Unit, Faculty of Medicine, Department of Public Health and Primary Care, KU Leuven, Kapucijnenvoer 35, Blok D, Box 7001, University of Leuven, Leuven, Belgium
| | - Cathrine Hoyo
- Department of Biological Sciences, Center for Human Health and the Environment, North Carolina State University, Campus Box 7633, Raleigh, NC 27633, USA
| | - Craig M. Butt
- Nicholas School of the Environment, Duke University, Box 90328, 450 Research Drive, Durham, NC 27708, USA
| | - Steffen Fieuws
- L-Biostat, Faculty of Medicine, Department of Public Health and Primary Care, KU Leuven - University of Leuven, Kapucijnenvoer 35, Leuven, Belgium
| | - Thomas M. Price
- Division of Reproductive Endocrinology and Infertility, Department of Obstetrics and Gynecology, Duke University Medical Center, Box 3143, Durham, NC 27713, USA
| | - Susan K. Murphy
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Duke University Medical Center, Box 91012, B223 LSRC, 450 Research Drive, Durham, NC 27708, USA
| | - Heather M. Stapleton
- Nicholas School of the Environment, Duke University, Box 90328, 450 Research Drive, Durham, NC 27708, USA
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12
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Cirillo A, Di Salle A, Petillo O, Melone MAB, Grimaldi G, Bellotti A, Torelli G, De' Santi MS, Cantatore G, Marinelli A, Galderisi U, Peluso G. High grade glioblastoma is associated with aberrant expression of ZFP57, a protein involved in gene imprinting, and of CPT1A and CPT1C that regulate fatty acid metabolism. Cancer Biol Ther 2014; 15:735-41. [PMID: 24618825 DOI: 10.4161/cbt.28408] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023] Open
Abstract
The diagnosis of glioblastoma is still based on tumor histology, but emerging molecular diagnosis is becoming an important part of glioblastoma classification. Besides the well-known cell cycle-related circuitries that are associated with glioblastoma onset and development, new insights may be derived by looking at pathways involved in regulation of epigenetic phenomena and cellular metabolism, which may both be highly deregulated in cancer cells. We evaluated if in glioblastoma patients the high grade of malignancy could be associated with aberrant expression of some genes involved in regulation of epigenetic phenomena and lipid metabolism. We measured the mRNA levels of ZFP57, TRIM28, CPT1A, CPT1B, and CPT1C in a cohort of 80 patients divided in two groups: grade II and grade IV. We evidenced that high grade glioblastoma is associated with increased level of ZFP57, a protein involved in gene imprinting, and aberrant expression of CPT1A and CPT1C, regulators of fatty acid oxidation. Our study may pave the way to identify new markers that could be potentially useful for diagnosis and/or prognosis of glioblastoma.
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Affiliation(s)
| | - Anna Di Salle
- Institute of Biomedicine and Bioresources; CNR; Naples, Italy
| | | | - Mariarosa A B Melone
- Institute of Biomedicine and Bioresources; CNR; Naples, Italy; Department of Clinical and Experimental Medicine; Second University of Naples; Naples, Italy
| | - Giovanna Grimaldi
- Institute of Genetics and Biophysics "Adriano Buzzati-Traverso"; CNR; Naples, Italy
| | | | | | | | - Giovanna Cantatore
- PO "Santa Maria di Loreto Mare"; Napoli, Italy; UO of Neurosurgery; AOU "San Giovanni di Dio e Ruggi di Aragona"; Salerno, Italy
| | - Alfredo Marinelli
- Department of Endocrinology and Clinical and Molecular Oncology; University "Federico II"; Naples, Italy
| | - Umberto Galderisi
- Institute of Biomedicine and Bioresources; CNR; Naples, Italy; Department of Experimental Medicine; Second University of Naples; Naples, Italy
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Soubry A, Murphy SK, Wang F, Huang Z, Vidal AC, Fuemmeler BF, Kurtzberg J, Murtha A, Jirtle RL, Schildkraut JM, Hoyo C. Newborns of obese parents have altered DNA methylation patterns at imprinted genes. Int J Obes (Lond) 2013; 39:650-7. [PMID: 24158121 PMCID: PMC4048324 DOI: 10.1038/ijo.2013.193] [Citation(s) in RCA: 214] [Impact Index Per Article: 19.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/04/2013] [Revised: 09/25/2013] [Accepted: 10/06/2013] [Indexed: 12/14/2022]
Abstract
Background: Several epidemiologic studies have demonstrated associations between periconceptional environmental exposures and health status of the offspring in later life. Although these environmentally related effects have been attributed to epigenetic changes, such as DNA methylation shifts at imprinted genes, little is known about the potential effects of maternal and paternal preconceptional overnutrition or obesity. Objective: We examined parental preconceptional obesity in relation to DNA methylation profiles at multiple human imprinted genes important in normal growth and development, such as: maternally expressed gene 3 (MEG3), mesoderm-specific transcript (MEST), paternally expressed gene 3 (PEG3), pleiomorphic adenoma gene-like 1 (PLAGL1), epsilon sarcoglycan and paternally expressed gene 10 (SGCE/PEG10) and neuronatin (NNAT). Methods: We measured methylation percentages at the differentially methylated regions (DMRs) by bisulfite pyrosequencing in DNA extracted from umbilical cord blood leukocytes of 92 newborns. Preconceptional obesity, defined as BMI ⩾30 kg m−2, was ascertained through standardized questionnaires. Results: After adjusting for potential confounders and cluster effects, paternal obesity was significantly associated with lower methylation levels at the MEST (β=−2.57; s.e.=0.95; P=0.008), PEG3 (β=−1.71; s.e.=0.61; P=0.005) and NNAT (β=−3.59; s.e.=1.76; P=0.04) DMRs. Changes related to maternal obesity detected at other loci were as follows: β-coefficient was +2.58 (s.e.=1.00; P=0.01) at the PLAGL1 DMR and −3.42 (s.e.=1.69; P=0.04) at the MEG3 DMR. Conclusion: We found altered methylation outcomes at multiple imprint regulatory regions in children born to obese parents, compared with children born to non-obese parents. In spite of the small sample size, our data suggest a preconceptional influence of parental life-style or overnutrition on the (re)programming of imprint marks during gametogenesis and early development. More specifically, the significant and independent association between paternal obesity and the offspring's methylation status suggests the susceptibility of the developing sperm for environmental insults. The acquired imprint instability may be carried onto the next generation and increase the risk for chronic diseases in adulthood.
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Affiliation(s)
- A Soubry
- 1] Duke Cancer Institute, Duke University Medical Center, Durham, NC, USA [2] Epidemiology Research Group, Department of Public Health and Primary Care, Faculty of Medicine, KULeuven, Leuven, Belgium
| | - S K Murphy
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Duke University Medical Center, Durham, NC, USA
| | - F Wang
- Duke Cancer Institute, Duke University Medical Center, Durham, NC, USA
| | - Z Huang
- Department of Obstetrics and Gynecology, Division of Gynecologic Oncology, Duke University Medical Center, Durham, NC, USA
| | - A C Vidal
- Department of Obstetrics and Gynecology, Division of Clinical and Epidemiologic Research and Cancer Prevention, Duke University Medical Center, Durham, NC, USA
| | - B F Fuemmeler
- Department of Community and Family Medicine, Duke University Medical Center, Durham, NC, USA
| | - J Kurtzberg
- Carolinas Cord Blood Bank, Robertson Cell and Translational Therapy Program, Duke Translational Research Institute, Duke University Medical Center, Durham, NC, USA
| | - A Murtha
- Department of Obstetrics and Gynecology, Division of Maternal and Fetal Medicine, Duke University Medical Center, Durham, NC, USA
| | - R L Jirtle
- Department of Oncology, McArdle Laboratory for Cancer Research, University of Wisconsin, Madison, WI, USA
| | - J M Schildkraut
- 1] Duke Cancer Institute, Duke University Medical Center, Durham, NC, USA [2] Department of Community and Family Medicine, Duke University Medical Center, Durham, NC, USA
| | - C Hoyo
- Department of Obstetrics and Gynecology, Division of Clinical and Epidemiologic Research and Cancer Prevention, Duke University Medical Center, Durham, NC, USA
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14
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Nye MD, Hoyo C, Huang Z, Vidal AC, Wang F, Overcash F, Smith JS, Vasquez B, Hernandez B, Swai B, Oneko O, Mlay P, Obure J, Gammon MD, Bartlett JA, Murphy SK. Associations between methylation of paternally expressed gene 3 (PEG3), cervical intraepithelial neoplasia and invasive cervical cancer. PLoS One 2013; 8:e56325. [PMID: 23418553 PMCID: PMC3571954 DOI: 10.1371/journal.pone.0056325] [Citation(s) in RCA: 63] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2012] [Accepted: 01/08/2013] [Indexed: 11/18/2022] Open
Abstract
Cytology-based screening for invasive cervical cancer (ICC) lacks sensitivity and specificity to discriminate between cervical intraepithelial neoplasia (CIN) likely to persist or progress from cases likely to resolve. Genome-wide approaches have been used to identify DNA methylation marks associated with CIN persistence or progression. However, associations between DNA methylation marks and CIN or ICC remain weak and inconsistent. Between 2008-2009, we conducted a hospital-based, case-control study among 213 Tanzania women with CIN 1/2/3 or ICC. We collected questionnaire data, biopsies, peripheral blood, cervical scrapes, Human papillomavirus (HPV) and HIV-1 infection status. We assessed PEG3 methylation status by bisulfite pyrosequencing. Multinomial logistic regression was used to estimate odds ratios (OR) and confidence intervals (CI 95%) for associations between PEG3 methylation status and CIN or ICC. After adjusting for age, gravidity, hormonal contraceptive use and HPV infection, a 5% increase in PEG3 DNA methylation was associated with increased risk for ICC (OR = 1.6; 95% CI 1.2-2.1). HPV infection was associated with a higher risk of CIN1-3 (OR = 15.7; 95% CI 5.7-48.6) and ICC (OR = 29.5, 95% CI 6.3-38.4). Infection with high risk HPV was correlated with mean PEG3 differentially methylated regions (DMRs) methylation (r = 0.34 p<0.0001), while the correlation with low risk HPV infection was weaker (r = 0.16 p = 0.047). Although small sample size limits inference, these data support that PEG3 methylation status has potential as a molecular target for inclusion in CIN screening to improve prediction of progression. Impact statement: We present the first evidence that aberrant methylation of the PEG3 DMR is an important co-factor in the development of Invasive cervical carcinoma (ICC), especially among women infected with high risk HPV. Our results show that a five percent increase in DNA methylation of PEG3 is associated with a 1.6-fold increase ICC risk. Suggesting PEG3 methylation status may be useful as a molecular marker for CIN screening to improve prediction of cases likely to progress.
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Affiliation(s)
- Monica D. Nye
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Duke University School of Medicine, Durham, North Carolina, United States of America
- Lineberger Comprehensive Cancer Center, University of North Carolina at Chapel Hill, North Carolina, United States of America
| | - Cathrine Hoyo
- Department of Obstetrics and Gynecology, Program of Cancer Detection, Prevention and Control, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Zhiqing Huang
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Adriana C. Vidal
- Department of Obstetrics and Gynecology, Program of Cancer Detection, Prevention and Control, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Frances Wang
- Duke Comprehensive Cancer Center, Duke University Medical Center, Durham, North Carolina, United States of America
| | - Francine Overcash
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Jennifer S. Smith
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - Brandi Vasquez
- Kilmanjaro Christian Medical Center, Moshi, Tanzania
- Duke Women's Health Collaboration, Durham, North Carolina, United States of America
| | - Brenda Hernandez
- Cancer Research Center of Hawaii, University of Hawaii, Honolulu, Hawaii, United States of America
| | - Britta Swai
- Department of Pathology, Kilimanjaro Christian Medical Centre, Tumaini University, Moshi, Tanzania
| | - Olola Oneko
- Department of Obstetrics and Gynecology, Kilimanjaro Christian Medical Centre, Tumaini University, Moshi, Tanzania
| | - Pendo Mlay
- Department of Obstetrics and Gynecology, Kilimanjaro Christian Medical Centre, Tumaini University, Moshi, Tanzania
| | - Joseph Obure
- Department of Obstetrics and Gynecology, Kilimanjaro Christian Medical Centre, Tumaini University, Moshi, Tanzania
| | - Marilie D. Gammon
- Department of Epidemiology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina, United States of America
| | - John A. Bartlett
- Division of Infectious Diseases, Department of Medicine and Duke Global Health Institute, Duke University School of Medicine, Durham, North Carolina, United States of America
| | - Susan K. Murphy
- Division of Gynecologic Oncology, Department of Obstetrics and Gynecology, Duke University School of Medicine, Durham, North Carolina, United States of America
- * E-mail:
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15
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Thiaville MM, Kim J. Oncogenic potential of yin yang 1 mediated through control of imprinted genes. Crit Rev Oncog 2012; 16:199-209. [PMID: 22248054 DOI: 10.1615/critrevoncog.v16.i3-4.40] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
The transcription factor Yin Yang (YY) 1 is one of the most evolutionarily well-conserved DNA binding proteins that is ubiquitously expressed among different tissue types. YY1 functions as a critical regulator for a diverse set of genes, making its role in the cancerous environment elusive. Recent studies have demonstrated that clusters of YY1 binding sites are overrepresented in imprinted gene loci. These clustered binding sites may function as a molecular rheostat with respect to YY1 protein levels. YY1 levels were documented to be altered in various tumor tissues in conjunction with the transcriptional levels of the imprinted genes it regulates. This review highlights the unexplored mechanism through which fluctuations in YY1 protein levels alter the transcriptional status of imprinted genes containing clustered YY1 binding sites, which potentially could affect cancer development and/or progression.
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Affiliation(s)
- Michelle M Thiaville
- Department of Biological Sciences, Louisiana State University, Baton Rouge, Louisiana 70803, USA
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16
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Specific changes in the expression of imprinted genes in prostate cancer--implications for cancer progression and epigenetic regulation. Asian J Androl 2012; 14:436-50. [PMID: 22367183 DOI: 10.1038/aja.2011.160] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022] Open
Abstract
Epigenetic dysregulation comprising DNA hypermethylation and hypomethylation, enhancer of zeste homologue 2 (EZH2) overexpression and altered patterns of histone modifications is associated with the progression of prostate cancer. DNA methylation, EZH2 and histone modifications also ensure the parental-specific monoallelic expression of at least 62 imprinted genes. Although it is therefore tempting to speculate that epigenetic dysregulation may extend to imprinted genes, expression changes in cancerous prostates are only well documented for insulin-like growth factor 2 (IGF2). A literature and database survey on imprinted genes in prostate cancer suggests that the expression of most imprinted genes remains unchanged despite global disturbances in epigenetic mechanisms. Instead, selective genetic and epigenetic changes appear to lead to the inactivation of a sub-network of imprinted genes, which might function in the prostate to limit cell growth induced via the PI3K/Akt pathway, modulate androgen responses and regulate differentiation. Whereas dysregulation of IGF2 may constitute an early change in prostate carcinogenesis, inactivation of this imprinted gene network is rather associated with cancer progression.
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Abstract
Genomic imprinting is an epigenetic marking of genes in the parental germline that ensures the stable transmission of monoallelic gene expression patterns in a parent-of-origin-specific manner. Epigenetic marking systems are thus able to regulate gene activity independently of the underlying DNA sequence. Several imprinted gene products regulate cell proliferation and fetal growth; loss of their imprinted state, which effectively alters their dosage, might promote or suppress tumourigenic processes. Conversely, global epigenetic changes that underlie tumourigenesis might affect imprinted gene expression. Here, we review imprinted genes with regard to their roles in epigenetic predisposition to cancer, and discuss acquired epigenetic changes (DNA methylation, histone modifications and chromatin conformation) either as a result of cancer or as an early event in neoplasia. We also address recent work showing the potential role of noncoding RNA in modifying chromatin and affecting imprinted gene expression, and summarise the effects of loss of imprinting in cancer with regard to the roles that imprinted genes play in regulating growth signalling cascades. Finally, we speculate on the clinical applications of epigenetic drugs in cancer.
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18
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Laffaire J, Everhard S, Idbaih A, Crinière E, Marie Y, de Reyniès A, Schiappa R, Mokhtari K, Hoang-Xuan K, Sanson M, Delattre JY, Thillet J, Ducray F. Methylation profiling identifies 2 groups of gliomas according to their tumorigenesis. Neuro Oncol 2010; 13:84-98. [PMID: 20926426 DOI: 10.1093/neuonc/noq110] [Citation(s) in RCA: 101] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023] Open
Abstract
Extensive genomic and gene expression studies have been performed in gliomas, but the epigenetic alterations that characterize different subtypes of gliomas remain largely unknown. Here, we analyzed the methylation patterns of 807 genes (1536 CpGs) in a series of 33 low-grade gliomas (LGGs), 36 glioblastomas (GBMs), 8 paired initial and recurrent gliomas, and 9 controls. This analysis was performed with Illumina's Golden Gate Bead methylation arrays and was correlated with clinical, histological, genomic, gene expression, and genotyping data, including IDH1 mutations. Unsupervised hierarchical clustering resulted in 2 groups of gliomas: a group corresponding to de novo GBMs and a group consisting of LGGs, recurrent anaplastic gliomas, and secondary GBMs. When compared with de novo GBMs and controls, this latter group was characterized by a very high frequency of IDH1 mutations and by a hypermethylated profile similar to the recently described glioma CpG island methylator phenotype. MGMT methylation was more frequent in this group. Among the LGG cluster, 1p19q codeleted LGG displayed a distinct methylation profile. A study of paired initial and recurrent gliomas demonstrated that methylation profiles were remarkably stable across glioma evolution, even during anaplastic transformation, suggesting that epigenetic alterations occur early during gliomagenesis. Using the Cancer Genome Atlas data set, we demonstrated that GBM samples that had an LGG-like hypermethylated profile had a high rate of IDH1 mutations and a better outcome. Finally, we identified several hypermethylated and downregulated genes that may be associated with LGG and GBM oncogenesis, LGG oncogenesis, 1p19q codeleted LGG oncogenesis, and GBM oncogenesis.
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Affiliation(s)
- Julien Laffaire
- Université Pierre et Marie Curie-Paris 6, Centre de Recherche de l'Institut du Cerveau et de la Moëlle épinière (CRICM) UMR-S975, 75013 Paris, France.
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Sukumaran S, Xue B, Jusko WJ, Dubois DC, Almon RR. Circadian variations in gene expression in rat abdominal adipose tissue and relationship to physiology. Physiol Genomics 2010; 42A:141-52. [PMID: 20682845 DOI: 10.1152/physiolgenomics.00106.2010] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Circadian rhythms occur in all levels of organization from expression of genes to complex physiological processes. Although much is known about the mechanism of the central clock in the suprachiasmatic nucleus, the regulation of clocks present in peripheral tissues as well as the genes regulated by those clocks is still unclear. In this study, the circadian regulation of gene expression was examined in rat adipose tissue. A rich time series involving 54 animals euthanized at 18 time points within the 24-h cycle (12:12 h light-dark) was performed. mRNA expression was examined with Affymetrix gene array chips and quantitative real-time PCR, along with selected physiological measurements. Transcription factors involved in the regulation of central rhythms were examined, and 13 showed circadian oscillations. Mining of microarray data identified 190 probe sets that showed robust circadian oscillations. Circadian regulated probe sets were further parsed into seven distinct temporal clusters, with >70% of the genes showing maximum expression during the active/dark period. These genes were grouped into eight functional categories, which were examined within the context of their temporal expression. Circadian oscillations were also observed in plasma leptin, corticosterone, insulin, glucose, triglycerides, free fatty acids, and LDL cholesterol. Circadian oscillation in these physiological measurements along with the functional categorization of these genes suggests an important role for circadian rhythms in controlling various functions in white adipose tissue including adipogenesis, energy metabolism, and immune regulation.
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Affiliation(s)
- Siddharth Sukumaran
- Department of Biological Sciences, State University of New York at Buffalo, Buffalo, NY 14260, USA
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20
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Abstract
Epigenetic mechanisms involving DNA methylation, histone modifications and noncoding RNAs regulate and maintain gene-expression states. Similar to genetic mutations, alterations in epigenetic regulation can lead to uncontrolled cell division, tumor initiation and growth, invasiveness and metastasis. Research in brain cancer, particularly gliomas, has uncovered global and gene-specific DNA hypomethylation, local DNA hypermethylation of gene promoters and the de-regulation of microRNA expression. Understanding epigenetic dysregulation in brain cancers has provided new tools for prognostication, as well as suggesting new approaches to therapy. There is significant interest in new sequencing-based technologies that map genetic and epigenetic alterations comprehensively and at high resolution. These methods are being applied to brain tumors, and will better define the contribution of epigenetic defects to tumorigenesis.
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Affiliation(s)
- Shaun D Fouse
- Brain Tumor Research Center, Department of Neurosurgery, Helen Diller Family Comprehensive Cancer Center, University of California San Francisco, San Francisco, CA 94158, USA
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