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2.
Nat Cell Biol ; 26(4): 613-627, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38429478

RESUMO

The ability of tumour cells to thrive in harsh microenvironments depends on the utilization of nutrients available in the milieu. Here we show that pancreatic cancer-associated fibroblasts (CAFs) regulate tumour cell metabolism through the secretion of acetate, which can be blocked by silencing ATP citrate lyase (ACLY) in CAFs. We further show that acetyl-CoA synthetase short-chain family member 2 (ACSS2) channels the exogenous acetate to regulate the dynamic cancer epigenome and transcriptome, thereby facilitating cancer cell survival in an acidic microenvironment. Comparative H3K27ac ChIP-seq and RNA-seq analyses revealed alterations in polyamine homeostasis through regulation of SAT1 gene expression and enrichment of the SP1-responsive signature. We identified acetate/ACSS2-mediated acetylation of SP1 at the lysine 19 residue that increased SP1 protein stability and transcriptional activity. Genetic or pharmacologic inhibition of the ACSS2-SP1-SAT1 axis diminished the tumour burden in mouse models. These results reveal that the metabolic flexibility imparted by the stroma-derived acetate enabled cancer cell survival under acidosis via the ACSS2-SP1-SAT1 axis.


Assuntos
Fibroblastos Associados a Câncer , Neoplasias Pancreáticas , Animais , Camundongos , Fibroblastos Associados a Câncer/metabolismo , Linhagem Celular Tumoral , Acetatos/farmacologia , Acetatos/metabolismo , Neoplasias Pancreáticas/genética , Poliaminas , Microambiente Tumoral
3.
Dev Psychobiol ; 66(3): e22482, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38482889

RESUMO

Early life deprivation and stress can contribute to life-long, problematic consequences, including epigenetic variations related to behavior and health. Domestic dogs share human environments and social-cognitive traits, making them a promising comparative model to examine developmental plasticity. We examined 47 owner-dog dyads, including dogs rescued from abusive or neglectful environments, and matched control dogs for changes in DNA methylation of glucocorticoid (NR3C1) and oxytocin (OXTR) receptor genes previously shown to be affected by early life stress in other species including humans. We used an attachment paradigm, which included a separation event to examine cortisol levels and owner-dog attachment styles. Overall, dogs with adverse histories had different NR3C1 methylation patterns as a function of age and less OXTR methylation than comparison dogs. Dogs with adverse histories did not differ in their cortisol change from baseline to poststressor from comparison dogs, but the change in cortisol was associated with NR3C1 methylation. In addition, dogs with a history of early life stress had more insecure attachment styles; for every unit increase of OXTR methylation, the odds increased for insecure attachment style. This study demonstrates that adverse life histories lead to methylation differences, resulting in the hypothalamic-pituitary-adrenal (HPA) axis's dysregulation and differences in behavioral phenotypes.


Assuntos
Glucocorticoides , Receptores de Ocitocina , Humanos , Cães , Animais , Receptores de Ocitocina/genética , Ocitocina/metabolismo , Hidrocortisona , Receptores de Glucocorticoides/genética , Metilação de DNA
4.
Oncogene ; 41(30): 3747-3760, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35754042

RESUMO

Aberrant transcriptional activity of androgen receptor (AR) is one of the dominant mechanisms for developing of castration-resistant prostate cancer (CRPC). Analyzing AR-transcriptional complex related to CRPC is therefore important towards understanding the mechanism of therapy resistance. While studying its mechanism, we observed that a transmembrane protein called neuropilin-2 (NRP2) plays a contributory role in forming a novel AR-transcriptional complex containing nuclear pore proteins. Using immunogold electron microscopy, high-resolution confocal microscopy, chromatin immunoprecipitation, proteomics, and other biochemical techniques, we delineated the molecular mechanism of how a specific splice variant of NRP2 becomes sumoylated upon ligand stimulation and translocates to the inner nuclear membrane. This splice variant of NRP2 then stabilizes the complex between AR and nuclear pore proteins to promote CRPC specific gene expression. Both full-length and splice variants of AR have been identified in this specific transcriptional complex. In vitro cell line-based assays indicated that depletion of NRP2 not only destabilizes the AR-nuclear pore protein interaction but also inhibits the transcriptional activities of AR. Using an in vivo bone metastasis model, we showed that the inhibition of NRP2 led to the sensitization of CRPC cells toward established anti-AR therapies such as enzalutamide. Overall, our finding emphasize the importance of combinatorial inhibition of NRP2 and AR as an effective therapeutic strategy against treatment refractory prostate cancer.


Assuntos
Neoplasias de Próstata Resistentes à Castração , Androgênios/farmacologia , Linhagem Celular Tumoral , Humanos , Masculino , Neuropilina-2/genética , Neoplasias de Próstata Resistentes à Castração/metabolismo , Receptores Androgênicos/genética , Receptores Androgênicos/metabolismo , Transdução de Sinais
5.
J Biol Chem ; 298(5): 101890, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35378132

RESUMO

The unfolded protein response (UPR) is an adaptation mechanism activated to resolve transient accumulation of unfolded/misfolded proteins in the endoplasmic reticulum. Failure to resolve the transient accumulation of such proteins results in UPR-mediated programmed cell death. Loss of tumor suppressor gene or oncogene addiction in cancer cells can result in sustained higher basal UPR levels; however, it is not clear if these higher basal UPR levels in cancer cells can be exploited as a therapeutic strategy. We hypothesized that covalent modification of surface-exposed cysteine (SEC) residues could simulate unfolded/misfolded proteins to activate the UPR, and that higher basal UPR levels in cancer cells would provide the necessary therapeutic window. To test this hypothesis, here we synthesized analogs that can covalently modify multiple SEC residues and evaluated them as UPR activators. We identified a spirocyclic dimer, SpiD7, and evaluated its effects on UPR activation signals, that is, XBP1 splicing, phosphorylation of eIF2α, and a decrease in ATF 6 levels, in normal and cancer cells, which were further confirmed by RNA-Seq analyses. We found that SpiD7 selectively induced caspase-mediated apoptosis in cancer cells, whereas normal cells exhibited robust XBP1 splicing, indicating adaptation to stress. Furthermore, SpiD7 inhibited the growth of high-grade serous carcinoma cell lines ~3-15-fold more potently than immortalized fallopian tube epithelial (paired normal control) cells and reduced clonogenic growth of high-grade serous carcinoma cell lines. Our results suggest that induction of the UPR by covalent modification of SEC residues represents a cancer cell vulnerability and can be exploited to discover novel therapeutics.


Assuntos
Apoptose , Carcinoma , Resposta a Proteínas não Dobradas , Carcinoma/tratamento farmacológico , Carcinoma/metabolismo , Linhagem Celular Tumoral , Descoberta de Drogas , Retículo Endoplasmático/metabolismo , Estresse do Retículo Endoplasmático , Fator de Iniciação 2 em Eucariotos/metabolismo , Humanos
6.
RSC Chem Biol ; 3(1): 32-36, 2022 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-35128406

RESUMO

Tumor necrosis factor (TNF) α-induced nuclear translocation of the NF-κB subunit RELA has been implicated in several pathological conditions. Here we report the discovery of a spirocyclic dimer (SpiD7) that covalently modifies RELA to inhibit TNFα-induced nuclear translocation. This is a previously unexplored strategy to inhibit TNFα-induced NF-κB activation.

7.
Acta Neuropathol Commun ; 9(1): 195, 2021 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-34922631

RESUMO

Haploinsufficiency of chromosome 17p and c-Myc amplification distinguish group 3 medulloblastomas which are associated with early metastasis, rapid recurrence, and swift mortality. Tumor suppressor genes on this locus have not been adequately characterized. We elucidated the role of miR-212-3p in the pathophysiology of group 3 tumors. First, we learned that miR-212-3p undergoes epigenetic silencing by histone modifications in group 3 tumors. Restoring its expression reduced cancer cell proliferation, migration, colony formation, and wound healing in vitro and attenuated tumor burden and improved survival in vivo. MiR-212-3p also triggered c-Myc destabilization and degradation, leading to elevated apoptosis. We then isolated an oncogenic target of miR-212-3p, i.e. NFIB, a nuclear transcription factor implicated in metastasis and recurrence in various cancers. Increased expression of NFIB was confirmed in group 3 tumors and associated with poor survival. NFIB silencing reduced cancer cell proliferation, migration, and invasion. Concurrently, reduced medullosphere formation and stem cell markers (Nanog, Oct4, Sox2, CD133) were noted. These results substantiate the tumor-suppressive role of miR-212-3p in group 3 MB and identify a novel oncogenic target implicated in metastasis and tumor recurrence.


Assuntos
Neoplasias Cerebelares/metabolismo , Regulação Neoplásica da Expressão Gênica/genética , Meduloblastoma/metabolismo , MicroRNAs/metabolismo , Fatores de Transcrição NFI/metabolismo , Animais , Células Cultivadas , Neoplasias Cerebelares/genética , Modelos Animais de Doenças , Humanos , Meduloblastoma/genética , Camundongos , MicroRNAs/genética , Fatores de Transcrição NFI/genética
8.
Nat Microbiol ; 5(10): 1271-1284, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32661313

RESUMO

Staphylococcus aureus is a leading cause of biofilm-associated prosthetic joint infection (PJI), resulting in considerable disability and prolonged treatment. It is known that host leukocyte IL-10 production is required for S. aureus biofilm persistence in PJI. An S. aureus bursa aurealis Tn library consisting of 1,952 non-essential genes was screened for mutants that failed to induce IL-10 in myeloid-derived suppressor cells (MDSCs), which identified a critical role for bacterial lactic acid biosynthesis. We generated an S. aureus ddh/ldh1/ldh2 triple Tn mutant that cannot produce D- or L-lactate. Co-culture of MDSCs or macrophages with ddh/ldh1/ldh2 mutant biofilm produced substantially less IL-10 compared with wild-type S. aureus, which was also observed in a mouse model of PJI and led to reduced biofilm burden. Using MDSCs recovered from the mouse PJI model and in vitro leukocyte-biofilm co-cultures, we show that bacterial-derived lactate inhibits histone deacetylase 11, causing unchecked HDAC6 activity and increased histone 3 acetylation at the Il-10 promoter, resulting in enhanced Il-10 transcription in MDSCs and macrophages. Finally, we show that synovial fluid of patients with PJI contains elevated amounts of D-lactate and IL-10 compared with control subjects, and bacterial lactate increases IL-10 production by human monocyte-derived macrophages.


Assuntos
Biofilmes , Histona Desacetilases/metabolismo , Interações Hospedeiro-Patógeno/imunologia , Ácido Láctico/metabolismo , Infecções Estafilocócicas/imunologia , Infecções Estafilocócicas/microbiologia , Staphylococcus aureus/fisiologia , Biomarcadores , Vias Biossintéticas , Citocinas/metabolismo , Mediadores da Inflamação/metabolismo , Macrófagos/imunologia , Macrófagos/metabolismo , Células Supressoras Mieloides/imunologia , Células Supressoras Mieloides/metabolismo , Infecções Estafilocócicas/metabolismo
9.
Epigenetics ; 15(12): 1325-1335, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32508251

RESUMO

Superoxide dismutase 3 (SOD3) is a secreted antioxidant enzyme that regulates reactive oxygen species in the microenvironment. It is also a potential tumour suppressor gene that is significantly downregulated in breast cancer. We have previously shown that its mRNA expression is inversely correlated with relapse free survival in breast cancer patients. This study aimed to investigate the correlation of SOD3 promoter DNA methylation with its expression in different molecular subtypes of breast carcinoma. We found that SOD3 expression was significantly reduced in breast carcinoma samples compared to normal tissues with the lowest levels observed in Luminal B subtype. Pyrosequencing analysis showed significant increase in methylation levels in the SOD3 promoter region (-108 and -19 from the TSS) in tumours vs normal tissues (53.6% vs 25.2%). The highest degree of correlation between methylation and SOD3 expression levels was observed in Luminal B subtype (Spearman's R = -0.540, P < 0.00093). In this subtype, the -78 CpG position is the most significantly methylated site. The Spearman's coefficient analysis also indicated the most significant correlation of DNA methylation at this site with SOD3 gene expression levels in tumours vs. normal tissues (R = -0.5816, P < 6.9E-12). Moreover, copy number variation analysis of TCGA database revealed that the more aggressive Triple Negative and Her2+ subtypes had higher levels of SOD3 gene deletion. The predominantly down-regulated expression pattern of SOD3 and the various genetic and epigenetic deregulations of its expression suggest that loss of this antioxidant promotes an advantageous tumour-promoting microenvironment in breast cancer.


Assuntos
Neoplasias da Mama/genética , Carcinoma/genética , Metilação de DNA , Superóxido Dismutase/genética , Neoplasias da Mama/metabolismo , Regulação para Baixo , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , História Medieval , Humanos , Regiões Promotoras Genéticas , Superóxido Dismutase/metabolismo
10.
PLoS Genet ; 16(6): e1008808, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32497036

RESUMO

Metastasis is responsible for 90% of human cancer mortality, yet it remains a challenge to model human cancer metastasis in vivo. Here we describe mouse models of high-grade serous ovarian cancer, also known as high-grade serous carcinoma (HGSC), the most common and deadliest human ovarian cancer type. Mice genetically engineered to harbor Dicer1 and Pten inactivation and mutant p53 robustly replicate the peritoneal metastases of human HGSC with complete penetrance. Arising from the fallopian tube, tumors spread to the ovary and metastasize throughout the pelvic and peritoneal cavities, invariably inducing hemorrhagic ascites. Widespread and abundant peritoneal metastases ultimately cause mouse deaths (100%). Besides the phenotypic and histopathological similarities, mouse HGSCs also display marked chromosomal instability, impaired DNA repair, and chemosensitivity. Faithfully recapitulating the clinical metastases as well as molecular and genomic features of human HGSC, this murine model will be valuable for elucidating the mechanisms underlying the development and progression of metastatic ovarian cancer and also for evaluating potential therapies.


Assuntos
Antineoplásicos/farmacologia , Cistadenocarcinoma Seroso/genética , Neoplasias Ovarianas/patologia , Neoplasias Peritoneais/genética , Animais , Antineoplásicos/uso terapêutico , Linhagem Celular Tumoral , Instabilidade Cromossômica , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/secundário , RNA Helicases DEAD-box/genética , Reparo do DNA , Modelos Animais de Doenças , Resistencia a Medicamentos Antineoplásicos/genética , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Estudos de Viabilidade , Feminino , Humanos , Camundongos , Camundongos Knockout , Mutação , Gradação de Tumores , Metástase Neoplásica/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , PTEN Fosfo-Hidrolase/genética , Neoplasias Peritoneais/tratamento farmacológico , Neoplasias Peritoneais/secundário , Cultura Primária de Células , Ribonuclease III/genética , Proteína Supressora de Tumor p53/genética
11.
Proc Natl Acad Sci U S A ; 117(21): 11409-11420, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32404420

RESUMO

Formation of G-quadruplex (G4) DNA structures in key regulatory regions in the genome has emerged as a secondary structure-based epigenetic mechanism for regulating multiple biological processes including transcription, replication, and telomere maintenance. G4 formation (folding), stabilization, and unfolding must be regulated to coordinate G4-mediated biological functions; however, how cells regulate the spatiotemporal formation of G4 structures in the genome is largely unknown. Here, we demonstrate that endogenous oxidized guanine bases in G4 sequences and the subsequent activation of the base excision repair (BER) pathway drive the spatiotemporal formation of G4 structures in the genome. Genome-wide mapping of occurrence of Apurinic/apyrimidinic (AP) site damage, binding of BER proteins, and G4 structures revealed that oxidized base-derived AP site damage and binding of OGG1 and APE1 are predominant in G4 sequences. Loss of APE1 abrogated G4 structure formation in cells, which suggests an essential role of APE1 in regulating the formation of G4 structures in the genome. Binding of APE1 to G4 sequences promotes G4 folding, and acetylation of APE1, which enhances its residence time, stabilizes G4 structures in cells. APE1 subsequently facilitates transcription factor loading to the promoter, providing mechanistic insight into the role of APE1 in G4-mediated gene expression. Our study unravels a role of endogenous oxidized DNA bases and APE1 in controlling the formation of higher-order DNA secondary structures to regulate transcription beyond its well-established role in safeguarding the genomic integrity.


Assuntos
Dano ao DNA , Reparo do DNA/fisiologia , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/metabolismo , Quadruplex G , Células A549 , Acetilação , DNA Liase (Sítios Apurínicos ou Apirimidínicos)/genética , Expressão Gênica , Genes myc , Genoma Humano , Guanina/química , Guanina/metabolismo , Células HCT116 , Humanos , Oxirredução , Estresse Oxidativo/genética , Regiões Promotoras Genéticas , Proteínas Proto-Oncogênicas p21(ras)/genética , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo
12.
Cancers (Basel) ; 12(3)2020 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-32213861

RESUMO

A hallmark of human cancer is global DNA hypomethylation (GDHO), but the mechanisms accounting for this defect and its pathological consequences have not been investigated in human epithelial ovarian cancer (EOC). In EOC, GDHO was associated with advanced disease and reduced overall and disease-free survival. GDHO (+) EOC tumors displayed a proliferative gene expression signature, including FOXM1 and CCNE1 overexpression. Furthermore, DNA hypomethylation in these tumors was enriched within genomic blocks (hypomethylated blocks) that overlapped late-replicating regions, lamina-associated domains, PRC2 binding sites, and the H3K27me3 histone mark. Increased proliferation coupled with hypomethylated blocks at late-replicating regions suggests a passive hypomethylation mechanism. This hypothesis was further supported by our observation that cytosine DNA methyltransferases (DNMTs) and UHRF1 showed significantly reduced expression in GDHO (+) EOC after normalization to canonical proliferation markers, including MKI67. Finally, GDHO (+) EOC tumors had elevated chromosomal instability (CIN), and copy number alterations (CNA) were enriched at the DNA hypomethylated blocks. Together, these findings implicate a passive DNA demethylation mechanism in ovarian cancer that is associated with genomic instability and poor prognosis.

13.
Brain Pathol ; 30(4): 732-745, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32145124

RESUMO

Of the four primary subgroups of medulloblastoma, the most frequent cytogenetic abnormality, i17q, distinguishes Groups 3 and 4 which carry the highest mortality; haploinsufficiency of 17p13.3 is a marker for particularly poor prognosis. At the terminal end of this locus lies miR-1253, a brain-enriched microRNA that regulates bone morphogenic proteins during cerebellar development. We hypothesized miR-1253 confers novel tumor-suppressive properties in medulloblastoma. Using two different cohorts of medulloblastoma samples, we first studied the expression and methylation profiles of miR-1253. We then explored the anti-tumorigenic properties of miR-1253, in parallel with a biochemical analysis of apoptosis and proliferation, and isolated oncogenic targets using high-throughput screening. Deregulation of miR-1253 expression was noted, both in medulloblastoma clinical samples and cell lines, by epigenetic silencing via hypermethylation; specific de-methylation of miR-1253 not only resulted in rapid recovery of expression but also a sharp decline in tumor cell proliferation and target gene expression. Expression restoration also led to a reduction in tumor cell virulence, concomitant with activation of apoptotic pathways, cell cycle arrest and reduction of markers of proliferation. We identified two oncogenic targets of miR-1253, CDK6 and CD276, whose silencing replicated the negative trophic effects of miR-1253. These data reveal novel tumor-suppressive properties for miR-1253, i.e., (i) loss of expression via epigenetic silencing; (ii) negative trophic effects on tumor aggressiveness; and (iii) downregulation of oncogenic targets.


Assuntos
Antígenos B7/genética , Neoplasias Cerebelares/patologia , Quinase 6 Dependente de Ciclina/genética , Regulação Neoplásica da Expressão Gênica/genética , Meduloblastoma/patologia , MicroRNAs/genética , Proliferação de Células/genética , Neoplasias Cerebelares/genética , Humanos , Meduloblastoma/genética
14.
Sci Bull (Beijing) ; 65(15): 1281-1296, 2020 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34888112

RESUMO

Understanding the cell-of-origin of ovarian high grade serous cancer (HGSC) is the prerequisite for efficient prevention and early diagnosis of this most lethal gynecological cancer. Recently, a mesenchymal type of ovarian HGSC with the poorest prognosis among ovarian cancers was identified by both TCGA and AOCS studies. The cell-of-origin of this subtype of ovarian cancer is unknown. While pursuing studies to understand the role of the Hippo pathway in ovarian granulosa cell physiology and pathology, we unexpectedly found that the Yes-associated protein 1 (YAP1), the major effector of the Hippo signaling pathway, induced dedifferentiation and reprogramming of the ovarian granulosa cells, a unique type of ovarian follicular cells with mesenchymal lineage and high plasticity, leading to the development of high grade ovarian cancer with serous features. Our research results unveil a potential cell-of-origin for a subtype of HGSC with mesenchymal features.

15.
J Circadian Rhythms ; 17: 6, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31303884

RESUMO

INTRODUCTION: Women diagnosed with breast cancer (BC) are at increased risk of sleep deficiency. Approximately 30-60% of these women report poor sleep during and following surgery, chemotherapy, radiation therapy, and anti-estrogen therapy. The purpose of this study was to examine the relationship between genetic variation in circadian rhythm genes and self-reported sleep quality in women with BC. METHODS: This cross-sectional study recruited women with a first diagnosis of breast cancer at five sites in Nebraska and South Dakota. Sixty women were included in the study. Twenty-six circadian genes were selected for exome sequencing using the Nextera Rapid Capture Expanded Exome kit. 414 variants had a minor allele frequency of ≥5% and were included in the exploratory analysis. The association between Pittsburgh Sleep Quality Index (PSQI) score and genetic variants was determined by two-sample t-test or ANOVA. RESULTS: Twenty-five variants were associated with the PSQI score at p < 0.10, of which 19 were significant at p<0.05, although the associations did not reach statistical significance after adjustment for multiple comparisons. Variants associated with PSQI were from genes CSNK1D & E, SKP1, BHLHE40 & 41, NPAS2, ARNTL, MYRIP, KLHL30, TIMELESS, FBXL3, CUL1, PER1&2, RORB. Two genetic variants were synonymous or missense variants in the BHLHE40 and TIMELESS genes, respectively. CONCLUSIONS: These exploratory results demonstrate an association of genetic variants in circadian rhythm pathways with self-reported sleep in women with BC. Testing this association is warranted in a larger replication population.

16.
Epigenetics ; 14(2): 185-197, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30764732

RESUMO

The POTE gene family consists of 14 homologous genes localized to autosomal pericentromeres, and a sub-set of POTEs are cancer-testis antigen (CTA) genes. POTEs are over-expressed in epithelial ovarian cancer (EOC), including the high-grade serous subtype (HGSC), and expression of individual POTEs correlates with chemoresistance and reduced survival in HGSC. The mechanisms driving POTE overexpression in EOC and other cancers is unknown. Here, we investigated the role of epigenetics in regulating POTE expression, with a focus on DNA hypomethylation. Consistent with their pericentromeric localization, Pan-POTE expression in EOC correlated with expression of the pericentromeric repeat NBL2, which was not the case for non-pericentromeric CTAs. POTE genomic regions contain LINE-1 (L1) sequences, and Pan-POTE expression correlated with both global and POTE-specific L1 hypomethylation in EOC. Analysis of individual POTEs using RNA-seq and DNA methylome data from fallopian tube epithelia (FTE) and HGSC revealed that POTEs C, E, and F have increased expression in HGSC in conjunction with DNA hypomethylation at 5' promoter or enhancer regions. Moreover, POTEs C/E/F showed additional increased expression in recurrent HGSC in conjunction with 5' hypomethylation, using patient-matched samples. Experiments using decitabine treatment and DNMT knockout cell lines verified a functional contribution of DNA methylation to POTE repression, and epigenetic drug combinations targeting histone deacetylases (HDACs) and histone methyltransferases (HMTs) in combination with decitabine further increased POTE expression. In summary, several alterations of the cancer epigenome, including pericentromeric activation, global and locus-specific L1 hypomethylation, and locus-specific 5' CpG hypomethylation, converge to promote POTE expression in ovarian cancer.


Assuntos
Carcinoma Epitelial do Ovário/genética , Metilação de DNA , Neoplasias Ovarianas/genética , Proteínas/genética , Regulação para Cima , Linhagem Celular Tumoral , Epigênese Genética , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Elementos Nucleotídeos Longos e Dispersos , Regiões Promotoras Genéticas
17.
Sci Rep ; 8(1): 17136, 2018 11 20.
Artigo em Inglês | MEDLINE | ID: mdl-30459449

RESUMO

The POTE family includes 14 genes in three phylogenetic groups. We determined POTE mRNA expression in normal tissues, epithelial ovarian and high-grade serous ovarian cancer (EOC, HGSC), and pan-cancer, and determined the relationship of POTE expression to ovarian cancer clinicopathology. Groups 1 & 2 POTEs showed testis-specific expression in normal tissues, consistent with assignment as cancer-testis antigens (CTAs), while Group 3 POTEs were expressed in several normal tissues, indicating they are not CTAs. Pan-POTE and individual POTEs showed significantly elevated expression in EOC and HGSC compared to normal controls. Pan-POTE correlated with increased stage, grade, and the HGSC subtype. Select individual POTEs showed increased expression in recurrent HGSC, and POTEE specifically associated with reduced HGSC OS. Consistent with tumors, EOC cell lines had significantly elevated Pan-POTE compared to OSE and FTE cells. Notably, Group 1 & 2 POTEs (POTEs A/B/B2/C/D), Group 3 POTE-actin genes (POTEs E/F/I/J/KP), and other Group 3 POTEs (POTEs G/H/M) show within-group correlated expression, and pan-cancer analyses of tumors and cell lines confirmed this relationship. Based on their restricted expression in normal tissues and increased expression and association with poor prognosis in ovarian cancer, POTEs are potential oncogenes and therapeutic targets in this malignancy.


Assuntos
Antígenos de Neoplasias/genética , Neoplasias Ovarianas/genética , Proteínas Reguladoras de Apoptose/genética , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Família Multigênica , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Análise de Sobrevida
18.
Cell Signal ; 52: 137-146, 2018 12.
Artigo em Inglês | MEDLINE | ID: mdl-30223016

RESUMO

YES is a member of the SRC family kinase (SFK) group of non-receptor tyrosine kinases, which are implicated in multiple key cellular processes involved in oncogenesis. Antitubulin agents have been widely used as chemotherapeutics for cancer patients and these drugs arrest cells in mitosis, leading to subsequent cell death. In the present study, we define a mechanism for phospho-regulation of YES that is critical for its role in response to antitubulin agents. Specifically, we found that YES is phosphorylated at multiple sites on its N-terminal unique domain by the cell cycle kinase CDK1 during antitubulin drug-induced mitotic arrest. Phosphorylation of YES occurs during normal mitosis. Deletion of YES causes arrest in prometaphase and polyploidy in a p53-independent manner. We further show that YES regulates antitubulin chemosensitivity. Importantly, mitotic phosphorylation is essential for these effects. In support of our findings, we found that YES expression is high in recurrent ovarian cancer patients. Finally, through expression profiling, we documented that YES phosphorylation affects expression of multiple cell cycle regulators. Collectively, our results reveal a previously unrecognized mechanism for controlling the activity of YES during antitubulin chemotherapeutic treatment and suggest YES as a potential target for the treatment of antitubulin-resistant cancer.


Assuntos
Apoptose/efeitos dos fármacos , Proteína Quinase CDC2/metabolismo , Resistencia a Medicamentos Antineoplásicos , Mitose/efeitos dos fármacos , Nocodazol/farmacologia , Paclitaxel/farmacologia , Proteínas Proto-Oncogênicas c-yes/metabolismo , Moduladores de Tubulina/farmacologia , Antineoplásicos Fitogênicos/farmacologia , Células HCT116 , Células HEK293 , Células HeLa , Humanos , Nocodazol/uso terapêutico , Paclitaxel/uso terapêutico , Fosforilação , Proteínas Proto-Oncogênicas c-yes/genética , Moduladores de Tubulina/uso terapêutico
19.
J Matern Fetal Neonatal Med ; 31(4): 530-541, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28282769

RESUMO

OBJECTIVE: Preterm birth (PTB) is one of the leading causes of neonatal mortality and morbidity around the world. Epigenetic alterations of the human placenta may be involved in the causal chain of adverse pregnancy outcomes specifically PTB. In this systematic review, we investigated whether epigenetic dysregulation of the human placenta is associated with PTB. METHODS: We searched MEDLINE and EMBASE and systematically reviewed all relevant studies on epigenetic placental modifications in PTB. Two independent reviewers selected controlled human studies published in any language, evaluated their quality, and graded them using the Newcastle-Ottawa Quality Assessment Scale. We resolved disagreements by consensus with a third reviewer. RESULTS: Eleven observational studies of low to moderate quality met the eligibility criteria out of 60 unique studies. Most studies reported an association between placental epigenetic changes (methylation, mRNA and miRNA) and PTB, although research methods were highly heterogeneous. CONCLUSIONS: Studies reported various associations between specific epigenetic findings and PTB, although methodological concerns limited results' validity. Additional high quality studies are needed to assess the repeatability of these findings. The STROBE guidelines can be used to improve the quality of reporting.


Assuntos
Epigênese Genética , Placenta/metabolismo , Nascimento Prematuro/genética , Estudos de Casos e Controles , Feminino , Humanos , Metilação , MicroRNAs/metabolismo , Estudos Observacionais como Assunto , Gravidez , Nascimento Prematuro/etiologia , RNA Mensageiro/metabolismo
20.
FASEB J ; 31(12): 5371-5383, 2017 12.
Artigo em Inglês | MEDLINE | ID: mdl-28794174

RESUMO

Prenatal overnutrition affects development into adulthood and influences risk of obesity. We assessed the transgenerational effect of maternal Western diet (WD) consumption on offspring physical activity. Voluntary wheel running was increased in juvenile (4-7 wk of age), but decreased in adult (16-19 wk of age), F1 female WD offspring In contrast, no wheel-running differences in F1 male offspring were observed. Increased wheel running in juvenile female WD offspring was associated with up-regulated dopamine receptor (DRD)-1 and -2 in the nucleus accumbens (NAc) and with down-regulated Lepr in the ventral tegmental area (VTA). Conversely, decreased wheel running by adult female WD offspring was associated with down-regulated DRD1 in the NAc and with up-regulated Lepr in the VTA. Body fat, leptin, and insulin were increased in male, but not in female, F1 WD offspring. Recombinant virus (rAAV) leptin antagonism in the VTA decreased wheel running in standard diet but not in WD F1 female offspring. Analysis of F2 offspring found no differences in wheel running or adiposity in male or female offspring, suggesting that changes in the F1 generation were related to in utero somatic reprogramming. Our findings indicate prenatal WD exposure leads to age-specific changes in voluntary physical activity in female offspring that are differentially influenced by VTA leptin antagonism.-Ruegsegger, G. N., Grigsby, K. B., Kelty, T. J., Zidon, T. M., Childs, T. E., Vieira-Potter, V. J., Klinkebiel, D. L., Matheny, M., Scarpace, P. J., Booth, F. W. Maternal Western diet age-specifically alters female offspring voluntary physical activity and dopamine- and leptin-related gene expression.


Assuntos
Dieta Ocidental , Atividade Motora/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Pré-Natal , Receptores de Dopamina D1/metabolismo , Receptores de Dopamina D2/metabolismo , Receptores para Leptina/metabolismo , Animais , Composição Corporal , Regulação para Baixo , Feminino , Regulação da Expressão Gênica/efeitos dos fármacos , Leptina/genética , Leptina/metabolismo , Masculino , Atividade Motora/fisiologia , Núcleo Accumbens/metabolismo , Gravidez , Ratos , Receptores de Dopamina D1/genética , Receptores de Dopamina D2/genética , Receptores para Leptina/genética , Fatores Sexuais , Tegmento Mesencefálico/metabolismo , Regulação para Cima
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