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1.
Clin Epigenetics ; 15(1): 176, 2023 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-37924108

RESUMO

Facial aging is the most visible manifestation of aging. People desire to look younger than others of the same chronological age. Hence, perceived age is often used as a visible marker of aging, while biological age, often estimated by methylation markers, is used as an objective measure of age. Multiple epigenetics-based clocks have been developed for accurate estimation of general biological age and the age of specific organs, including the skin. However, it is not clear whether the epigenetic biomarkers (CpGs) used in these clocks are drivers of aging processes or consequences of aging. In this proof-of-concept study, we integrate data from GWAS on perceived facial aging and EWAS on CpGs measured in blood. By running EW Mendelian randomization, we identify hundreds of putative CpGs that are potentially causal to perceived facial aging with similar numbers of damaging markers that causally drive or accelerate facial aging and protective methylation markers that causally slow down or protect from aging. We further demonstrate that while candidate causal CpGs have little overlap with known epigenetics-based clocks, they affect genes or proteins with known functions in skin aging, such as skin pigmentation, elastin, and collagen levels. Overall, our results suggest that blood methylation markers reflect facial aging processes, and thus can be used to quantify skin aging and develop anti-aging solutions that target the root causes of aging.


Assuntos
Metilação de DNA , Envelhecimento da Pele , Humanos , Envelhecimento/genética , Epigênese Genética , Envelhecimento da Pele/genética , Face
2.
J Pain ; 24(9): 1721-1730, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37187218

RESUMO

Catechol-O-methyltransferase (COMT) is the major enzyme involved in the catabolism of dopamine, a neurotransmitter in the brain's reward system. The common COMT polymorphism Val158Met (rs4680 G>A) modulates pain response to opioids through a reward-motivated mechanism; however, its role in nonpharmacological pain medicine has not been clinically characterized. We genotyped 325 participants from a randomized controlled trial of cancer survivors with chronic musculoskeletal pain. We found that carrying methionine at position 158 (158Met) of COMT, encoded by the A allele, significantly increased the analgesic response to electroacupuncture (74% vs 50%; odds ratio [OR]: 2.79; 95% confidence interval [CI]: 1.31, 6.05; P < .01), but not to auricular acupuncture (68% vs 60%; OR: 1.43; 95% CI: .65, 3.12; P = .37) or usual care (24% vs 18%; OR: 1.46; 95% CI: .38, 7.24; P = .61) compared to Val/Val. These findings raise the possibility that COMT Val158Met might be an important predictor of analgesic response to electroacupuncture, providing novel insights into precision nonpharmacologic pain management tailored to individual genetic backgrounds. PERSPECTIVE: This work suggests the modulating effects of the polymorphism in COMT Val158Met on the response to acupuncture. Further research needs to validate these findings, increase the mechanistic understanding of acupuncture, and guide further development of acupuncture as a precision pain management strategy.


Assuntos
Terapia por Acupuntura , Sobreviventes de Câncer , Dor Crônica , Neoplasias , Humanos , Catecol O-Metiltransferase/genética , Dor Crônica/genética , Dor Crônica/terapia , Genótipo , Analgésicos Opioides , Polimorfismo de Nucleotídeo Único/genética
3.
Front Immunol ; 13: 880959, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36505421

RESUMO

Response to immunotherapy across multiple cancer types is approximately 25%, with some tumor types showing increased response rates compared to others (i.e. response rates in melanoma and non-small cell lung cancer (NSCLC) are typically 30-60%). Patients whose tumors are resistant to immunotherapy often lack high levels of pre-existing inflammation in the tumor microenvironment. Increased tumor glycolysis, acting through glucose deprivation and lactic acid accumulation, has been shown to have pleiotropic immune suppressive effects using in-vitro and in-vivo models of disease. To determine whether the immune suppressive effect of tumor glycolysis is observed across human solid tumors, we analyzed glycolytic and immune gene expression patterns in multiple solid malignancies. We found that increased expression of a glycolytic signature was associated with decreased immune infiltration and a more aggressive disease across multiple tumor types. Radiologic and pathologic analysis of untreated estrogen receptor (ER)-negative breast cancers corroborated these observations, and demonstrated that protein expression of glycolytic enzymes correlates positively with glucose uptake and negatively with infiltration of CD3+ and CD8+ lymphocytes. This study reveals an inverse relationship between tumor glycolysis and immune infiltration in a large cohort of multiple solid tumor types.


Assuntos
Neoplasias da Mama , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Feminino , Imunoterapia , Glicólise , Microambiente Tumoral
4.
J Pers Med ; 12(11)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36579561

RESUMO

Preeclampsia and gestational hypertensive disorders (GHD) are common complications of pregnancy that adversely affect maternal and offspring health, often with long-term consequences. High BMI, advanced age, and pre-existing conditions are known risk factors for GHD. Yet, assessing a woman's risk of GHD based on only these characteristics needs to be reevaluated in order to identify at-risk women, facilitate early diagnosis, and implement lifestyle recommendations. This study demonstrates that a risk score developed with machine learning from the case-control genetics dataset can be used as an early screening test for GHD. We further confirm BMI as a risk factor for GHD and investigate a relationship between GHD and genetically constructed anthropometric measures and biomarkers. Our results show that polygenic risk score can be used as an early screening tool that, together with other known risk factors and medical history, would assist in identifying women at higher risk of GHD before its onset to enable stratification of patients into low-risk and high-risk groups for monitoring and preventative programs to mitigate the risks.

5.
J Pers Med ; 12(9)2022 Aug 26.
Artigo em Inglês | MEDLINE | ID: mdl-36143166

RESUMO

Gestational diabetes mellitus (GDM) is a common complication of pregnancy that adversely affects maternal and offspring health. A variety of risk factors, such as BMI and age, have been associated with increased risks of gestational diabetes. However, in many cases, gestational diabetes occurs in healthy nulliparous women with no obvious risk factors. Emerging data suggest that the tendency to develop gestational diabetes has genetic and environmental components. Here we develop a polygenic risk score for GDM and investigate relationships between its genetic architecture and genetically constructed risk factors and biomarkers. Our results demonstrate that the polygenic risk score can be used as an early screening tool that identifies women at higher risk of GDM before its onset allowing comprehensive monitoring and preventative programs to mitigate the risks.

6.
Cancer Biother Radiopharm ; 35(6): 459-473, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32013538

RESUMO

An α particle-emitting nanodrug that is a potent and specific antitumor agent and also prompts significant remodeling of local immunity in the tumor microenvironment (TME) has been developed and may impact the treatment of melanoma. Biocompatible ultrasmall fluorescent core-shell silica nanoparticles (C' dots, diameter ∼6.0 nm) have been engineered to target the melanocortin-1 receptor expressed on melanoma through α melanocyte-stimulating hormone peptides attached to the C' dot surface. Actinium-225 is also bound to the nanoparticle to deliver a densely ionizing dose of high-energy α particles to cancer. Nanodrug pharmacokinetic properties are optimal for targeted radionuclide therapy as they exhibit rapid blood clearance, tumor-specific accumulation, minimal off-target localization, and renal elimination. Potent and specific tumor control, arising from the α particles, was observed in a syngeneic animal model of melanoma. Surprisingly, the C' dot component of this drug initiates a favorable pseudopathogenic response in the TME generating distinct changes in the fractions of naive and activated CD8 T cells, Th1 and regulatory T cells, immature dendritic cells, monocytes, MΦ and M1 macrophages, and activated natural killer cells. Concomitant upregulation of the inflammatory cytokine genome and adaptive immune pathways each describes a macrophage-initiated pseudoresponse to a viral-shaped pathogen. This study suggests that therapeutic α-particle irradiation of melanoma using ultrasmall functionalized core-shell silica nanoparticles potently kills tumor cells, and at the same time initiates a distinct immune response in the TME.


Assuntos
Partículas alfa/uso terapêutico , Portadores de Fármacos/química , Melanoma Experimental/radioterapia , Compostos Radiofarmacêuticos/administração & dosagem , Neoplasias Cutâneas/radioterapia , Microambiente Tumoral/efeitos da radiação , Actínio/administração & dosagem , Actínio/farmacocinética , Animais , Linhagem Celular Tumoral/transplante , Biologia Computacional , Modelos Animais de Doenças , Relação Dose-Resposta à Radiação , Feminino , Regulação Neoplásica da Expressão Gênica/imunologia , Regulação Neoplásica da Expressão Gênica/efeitos da radiação , Humanos , Imunidade Celular/genética , Imunidade Celular/efeitos da radiação , Masculino , Dose Máxima Tolerável , Melanoma Experimental/genética , Melanoma Experimental/imunologia , Melanoma Experimental/patologia , Camundongos , Terapia de Alvo Molecular/métodos , Nanopartículas/química , RNA-Seq , Compostos Radiofarmacêuticos/farmacocinética , Receptor Tipo 1 de Melanocortina/antagonistas & inibidores , Receptor Tipo 1 de Melanocortina/metabolismo , Dióxido de Silício/química , Neoplasias Cutâneas/genética , Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/patologia , Distribuição Tecidual , Microambiente Tumoral/genética , Microambiente Tumoral/imunologia
7.
PLoS One ; 13(9): e0203965, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30248111

RESUMO

Previous studies show that LDH-A knockdown reduces orthotopic 4T1 breast tumor lactate and delays tumor growth and the development of metastases in nude mice. Here, we report significant changes in the tumor microenvironment (TME) and a more robust anti-tumor response in immune competent BALB/c mice. 4T1 murine breast cancer cells were transfected with shRNA plasmids directed against LDH-A (KD) or a scrambled control plasmid (NC). Cells were also transduced with dual luciferase-based reporter systems to monitor HIF-1 activity and the development of metastases by bioluminescence imaging, using HRE-sensitive and constitutive promoters, respectively. The growth and metastatic profile of orthotopic 4T1 tumors developed from these cell lines were compared and a primary tumor resection model was studied to simulate the clinical management of breast cancer. Primary tumor growth, metastasis formation and TME phenotype were significantly different in LDH-A KD tumors compared with controls. In LDH-A KD cells, HIF-1 activity, hexokinase 1 and 2 expression and VEGF secretion were reduced. Differences in the TME included lower HIF-1α expression that correlated with lower vascularity and pimonidazole staining, higher infiltration of CD3+ and CD4+ T cells and less infiltration of TAMs. These changes resulted in a greater delay in metastases formation and 40% long-term survivors (>20 weeks) in the LDH-A KD cohort following surgical resection of the primary tumor. We show for the first time that LDH-depletion inhibits the formation of metastases and prolongs survival of mice through changes in tumor microenvironment that modulate the immune response. We attribute these effects to diminished HIF-1 activity, vascularization, necrosis formation and immune suppression in immune competent animals. Gene-expression analyses from four human breast cancer datasets are consistent with these results, and further demonstrate the link between glycolysis and immune suppression in breast cancer.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , L-Lactato Desidrogenase/metabolismo , Neoplasias Mamárias Experimentais/imunologia , Neoplasias Mamárias Experimentais/metabolismo , Microambiente Tumoral/imunologia , Microambiente Tumoral/fisiologia , Animais , Neoplasias da Mama/metabolismo , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Feminino , Técnicas de Silenciamento de Genes , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , L-Lactato Desidrogenase/antagonistas & inibidores , L-Lactato Desidrogenase/genética , Lactato Desidrogenase 5 , Ácido Láctico/metabolismo , Neoplasias Mamárias Experimentais/patologia , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Nus , Metástase Neoplásica/imunologia , Metástase Neoplásica/patologia , Neovascularização Patológica , Transdução de Sinais
8.
PLoS One ; 12(5): e0176562, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28486549

RESUMO

Fibrolamellar hepatocellular carcinoma (FL-HCC) is a rare variant of HCC that most frequently affects young adults. Because of its rarity and an absence of preclinical models, our understanding of FL-HCC is limited. Our objective was to analyze chromosomal alterations and dysregulated gene expression in tumor specimens collected at a single center during two decades of experience with FL-HCC. We analyzed 38 specimens from 26 patients by array comparative genomic hybridiziation (aCGH) and 35 specimens from 15 patients by transcriptome sequencing (RNA-seq). All tumor specimens exhibited genomic instability, with a higher frequency of genomic amplifications or deletions in metastatic tumors. The regions encoding 71 microRNAs (miRs) were deleted in at least 25% of tumor specimens. Five of these recurrently deleted miRs targeted the insulin-like growth factor 2 mRNA-binding protein 1 (IGF2BP1) gene product, and a correlating 100-fold upregulation of IGF2BP1 mRNA was seen in tumor specimens. Transcriptome analysis demonstrated intrapatient tumor similarity, independent of recurrence site or time. The p53 tumor suppressor pathway was downregulated as demonstrated by both aCGH and RNA-seq analysis. Notch, EGFR, NRAS, and RB1 pathways were also significantly dysregulated in tumors compared with normal liver tissue. The findings illuminate the genomic and transcriptomic landscape of this rare disease and provide insight into dysregulated oncogenic pathways and potential therapeutic targets in FL-HCC.


Assuntos
Carcinoma Hepatocelular/genética , Perfilação da Expressão Gênica , Genes p53 , Genoma Humano , Proteínas de Ligação a RNA/genética , Transcriptoma , Adolescente , Adulto , Feminino , Humanos , Adulto Jovem
9.
J Clin Oncol ; 35(15): 1650-1659, 2017 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-28296584

RESUMO

Purpose The major causes of mortality after allogeneic hematopoietic-cell transplantation (allo-HCT) are relapse, graft-versus-host disease (GVHD), and infection. We have reported previously that alterations in the intestinal flora are associated with GVHD, bacteremia, and reduced overall survival after allo-HCT. Because intestinal bacteria are potent modulators of systemic immune responses, including antitumor effects, we hypothesized that components of the intestinal flora could be associated with relapse after allo-HCT. Methods The intestinal microbiota of 541 patients admitted for allo-HCT was profiled by means of 16S ribosomal sequencing of prospectively collected stool samples. We examined the relationship between abundance of microbiota species or groups of related species and relapse/progression of disease during 2 years of follow-up time after allo-HCT by using cause-specific proportional hazards in a retrospective discovery-validation cohort study. Results Higher abundance of a bacterial group composed mostly of Eubacterium limosum in the validation set was associated with a decreased risk of relapse/progression of disease (hazard ratio [HR], 0.82 per 10-fold increase in abundance; 95% CI, 0.71 to 0.95; P = .009). When the patients were categorized according to presence or absence of this bacterial group, presence also was associated with less relapse/progression of disease (HR, 0.52; 95% CI, 0.31 to 0.87; P = .01). The 2-year cumulative incidences of relapse/progression among patients with and without this group of bacteria were 19.8% and 33.8%, respectively. These associations remained significant in multivariable models and were strongest among recipients of T-cell-replete allografts. Conclusion We found associations between the abundance of a group of bacteria in the intestinal flora and relapse/progression of disease after allo-HCT. These might serve as potential biomarkers or therapeutic targets to prevent relapse and improve survival after allo-HCT.


Assuntos
Microbioma Gastrointestinal/fisiologia , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Neoplasias/microbiologia , Neoplasias/cirurgia , Biomarcadores Tumorais/metabolismo , Fezes/microbiologia , Feminino , Doença Enxerto-Hospedeiro/microbiologia , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/metabolismo , Estudos Retrospectivos , Transplante Homólogo
10.
Oncotarget ; 7(41): 66906-66921, 2016 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-27602498

RESUMO

The last decade has seen a marked rise in the use of cancer tissues obtained from research autopsies. Such resources have been invaluable for studying cancer evolution or the mechanisms of therapeutic resistance to targeted therapies. Degradation of biomolecules is a potential challenge to usage of cancer tissues obtained in the post-mortem setting and remains incompletely studied. We analysed the nucleic acid quality in 371 different frozen tissue samples collected from 80 patients who underwent a research autopsy, including eight normal tissue types, primary and metastatic tumors. Our results indicate that RNA integrity number (RIN) of normal tissues decline with the elongation of post-mortem interval (PMI) in a tissue-type specific manner. Unlike normal tissues, the RNA quality of cancer tissues is highly variable with respect to post-mortem interval. The kinetics of DNA damage also has tissue type-specific features. Moreover, while DNA degradation is an indicator of low RNA quality, the converse is not true. Finally, we show that despite RIN values as low as 5.0, robust data can be obtained by RNA sequencing that reliably discriminates expression signatures.


Assuntos
Autopsia , Neoplasias , Desnaturação de Ácido Nucleico , Ácidos Nucleicos/química , Patologia Clínica/normas , Humanos , Neoplasias/metabolismo , Estabilidade de RNA
11.
Nat Commun ; 7: 10391, 2016 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-26837003

RESUMO

The composition of the intestinal microbiota influences the development of inflammatory disorders. However, associating inflammatory diseases with specific microbial members of the microbiota is challenging, because clinically detectable inflammation and its treatment can alter the microbiota's composition. Immunologic checkpoint blockade with ipilimumab, a monoclonal antibody that blocks cytotoxic T-lymphocyte-associated antigen-4 (CTLA-4) signalling, is associated with new-onset, immune-mediated colitis. Here we conduct a prospective study of patients with metastatic melanoma undergoing ipilimumab treatment and correlate the pre-inflammation faecal microbiota and microbiome composition with subsequent colitis development. We demonstrate that increased representation of bacteria belonging to the Bacteroidetes phylum is correlated with resistance to the development of checkpoint-blockade-induced colitis. Furthermore, a paucity of genetic pathways involved in polyamine transport and B vitamin biosynthesis is associated with an increased risk of colitis. Identification of these biomarkers may enable interventions to reduce the risk of inflammatory complications following cancer immunotherapy.


Assuntos
Anticorpos Monoclonais/efeitos adversos , Colite/microbiologia , Microbioma Gastrointestinal/genética , Melanoma/tratamento farmacológico , RNA Ribossômico 16S/genética , Neoplasias Cutâneas/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Bacteroidaceae , Bacteroidetes/genética , Bacteroidetes/isolamento & purificação , Colite/induzido quimicamente , Feminino , Humanos , Ipilimumab , Masculino , Melanoma/secundário , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Análise de Sequência de RNA , Neoplasias Cutâneas/patologia
14.
Stem Cell Reports ; 4(4): 658-69, 2015 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-25754204

RESUMO

Epigenetic regulation of key transcriptional programs is a critical mechanism that controls hematopoietic development, and, thus, aberrant expression patterns or mutations in epigenetic regulators occur frequently in hematologic malignancies. We demonstrate that the Polycomb protein L3MBTL1, which is monoallelically deleted in 20q- myeloid malignancies, represses the ability of stem cells to drive hematopoietic-specific transcriptional programs by regulating the expression of SMAD5 and impairing its recruitment to target regulatory regions. Indeed, knockdown of L3MBTL1 promotes the development of hematopoiesis and impairs neural cell fate in human pluripotent stem cells. We also found a role for L3MBTL1 in regulating SMAD5 target gene expression in mature hematopoietic cell populations, thereby affecting erythroid differentiation. Taken together, we have identified epigenetic priming of hematopoietic-specific transcriptional networks, which may assist in the development of therapeutic approaches for patients with anemia.


Assuntos
Diferenciação Celular/genética , Proteínas Cromossômicas não Histona/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Hematopoese/genética , Células-Tronco Pluripotentes/citologia , Células-Tronco Pluripotentes/metabolismo , Proteína Smad5/metabolismo , Transcrição Gênica , Regulação para Baixo , Células Precursoras Eritroides/citologia , Células Precursoras Eritroides/metabolismo , Humanos , Imunofenotipagem , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Proteínas Repressoras , Proteína Smad5/genética , Proteínas Supressoras de Tumor
15.
J Natl Cancer Inst ; 106(9)2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25190728

RESUMO

BACKGROUND: There are conflicting reports on the impact of soy on breast carcinogenesis. This study examines the effects of soy supplementation on breast cancer-related genes and pathways. METHODS: Women (n = 140) with early-stage breast cancer were randomly assigned to soy protein supplementation (n = 70) or placebo (n = 70) for 7 to 30 days, from diagnosis until surgery. Adherence was determined by plasma isoflavones: genistein and daidzein. Gene expression changes were evaluated by NanoString in pre- and posttreatment tumor tissue. Genome-wide expression analysis was performed on posttreatment tissue. Proliferation (Ki67) and apoptosis (Cas3) were assessed by immunohistochemistry. RESULTS: Plasma isoflavones rose in the soy group (two-sided Wilcoxon rank-sum test, P < .001) and did not change in the placebo group. In paired analysis of pre- and posttreatment samples, 21 genes (out of 202) showed altered expression (two-sided Student's t-test, P < .05). Several genes including FANCC and UGT2A1 revealed different magnitude and direction of expression changes between the two groups (two-sided Student's t-test, P < .05). A high-genistein signature consisting of 126 differentially expressed genes was identified from microarray analysis of tumors. This signature was characterized by overexpression (>2-fold) of cell cycle transcripts, including those that promote cell proliferation, such as FGFR2, E2F5, BUB1, CCNB2, MYBL2, CDK1, and CDC20 (P < .01). Soy intake did not result in statistically significant changes in Ki67 or Cas3. CONCLUSIONS: Gene expression associated with soy intake and high plasma genistein defines a signature characterized by overexpression of FGFR2 and genes that drive cell cycle and proliferation pathways. These findings raise the concerns that in a subset of women soy could adversely affect gene expression in breast cancer.


Assuntos
Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/metabolismo , Carcinoma Ductal de Mama/tratamento farmacológico , Carcinoma Ductal de Mama/metabolismo , Suplementos Nutricionais/efeitos adversos , Genisteína/sangue , Receptor Tipo 2 de Fator de Crescimento de Fibroblastos/metabolismo , Proteínas de Soja/administração & dosagem , Proteínas de Soja/efeitos adversos , Adulto , Idoso , Apoptose/efeitos dos fármacos , Biomarcadores/sangue , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/sangue , Carcinoma Ductal de Mama/patologia , Caspase 3/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Isoflavonas/sangue , Antígeno Ki-67/metabolismo , Pessoa de Meia-Idade , Análise Serial de Tecidos , Regulação para Cima
16.
Mol Cancer Ther ; 13(8): 2073-80, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24899684

RESUMO

The majority of uveal melanomas carry oncogenic mutations in the G proteins GNAQ and GNA11, with consequent activation of the MAPK pathway. Selective MEK inhibitors, such as selumetinib, have shown clinical benefit in uveal melanoma. However, mechanisms of drug resistance limit their efficacy in some patients. Analysis of MEK inhibitor-resistant uveal melanoma cell lines revealed the induction of RAS protein expression and activity. This effect was mediated by the RNA helicase DDX43, which was remarkably overexpressed in these cells. Depletion of DDX43 in MEK inhibitor-resistant cells decreased RAS proteins and inhibited ERK and AKT pathways. On the contrary, ectopic expression of DDX43 in parental uveal melanoma cells induced RAS protein levels and rendered cells resistant to MEK inhibition. Similar to DDX43 depletion, downregulation of KRAS, HRAS, and NRAS inhibited downstream pathways in the resistant cells, overcoming mutant GNAQ signaling. We also analyzed the expression of DDX43 in liver metastases of patients with uveal melanoma by RT-PCR, and found a significant overexpression of DDX43 in patients who did not benefit from selumetinib therapy. In conclusion, DDX43 induces RAS protein expression and signaling, mediating a novel mechanism of MEK inhibitor resistance. The detection of DDX43 in patients with uveal melanoma could lead to more targeted therapies for this disease.


Assuntos
Antineoplásicos/farmacologia , Benzimidazóis/farmacologia , RNA Helicases DEAD-box/metabolismo , Neoplasias Hepáticas/enzimologia , Melanoma/enzimologia , Proteínas de Neoplasias/metabolismo , Neoplasias Uveais/enzimologia , Proteínas ras/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , RNA Helicases DEAD-box/genética , Resistencia a Medicamentos Antineoplásicos , Expressão Gênica , Humanos , Neoplasias Hepáticas/secundário , MAP Quinase Quinase Quinases/antagonistas & inibidores , MAP Quinase Quinase Quinases/metabolismo , Melanoma/secundário , Proteínas de Neoplasias/genética , Proteínas Proto-Oncogênicas c-akt/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-akt/metabolismo , Regulação para Cima , Neoplasias Uveais/patologia , Proteínas ras/genética
17.
Eur Urol ; 65(6): 1191-7, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23954088

RESUMO

BACKGROUND: Biomarkers based on detecting prostate cancer (PCa)-specific transcripts in blood are associated with inferior outcomes, but their validation in a clinical context is lacking. OBJECTIVE: To determine whether detecting enhanced transcripts for PCa in whole blood using an analytically valid assay has prognostic significance relative to circulating tumor cell (CTC) enumeration. DESIGN, SETTING, AND PARTICIPANTS: The detection of KLK3, KLK2, HOXB13, GRHL2, and FOXA1 in whole blood by reverse transcription polymerase chain reaction (RT-PCR) was studied in 97 men with metastatic castration-resistant PCa (mCRPC) as a prognostic factor for overall survival. INTERVENTION: The 2.5 ml of blood was collected in PAXgene tubes for total RNA extraction and 7.5 ml for CTC enumeration from patients with progressive mCRPC. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: PCa-enriched genes were detected using a sensitive RT-PCR assay in whole blood from patients with mCRPC. Analytical validity of the assay was established in a clinical laboratory environment. The frequency of detecting transcripts was compared to CTC enumeration using CellSearch in an independent data set and survival associations were explored by concordance probability estimate (CPE). RESULTS AND LIMITATIONS: Two or more genes were detected by PCR in 53% of patients (51 of 97; 95% confidence interval [CI], 43-63%), and unfavorable CTC counts (five of more cells) were seen in 46% (45 of 97; 95% CI, 36-56%). Importantly, transcripts were detectable in 11 of 52 patients with favorable CTC counts (21%; 95% CI, 8-35%). Transcript detection predicted overall survival in a proportional hazards model. Significantly, the predictive accuracy of RT-PCR detection in combination with CTC enumeration had a CPE of 0.752 (standard error: 0.038), although this was limited by the number of patients evaluated. CONCLUSIONS: This validated RT-PCR assay detecting prostate-specific RNA in whole blood is prognostic for survival and may assess patient risk in tandem with CellSearch CTC enumeration. Its clinical utility is being prospectively explored.


Assuntos
Biomarcadores Tumorais/sangue , Células Neoplásicas Circulantes , Neoplasias de Próstata Resistentes à Castração/genética , Neoplasias de Próstata Resistentes à Castração/patologia , RNA Mensageiro/sangue , Idoso , Idoso de 80 Anos ou mais , Proteínas de Ligação a DNA/genética , Fator 3-alfa Nuclear de Hepatócito/genética , Proteínas de Homeodomínio/genética , Humanos , Calicreínas/genética , Masculino , Pessoa de Meia-Idade , Metástase Neoplásica , Prognóstico , Antígeno Prostático Específico/genética , Neoplasias de Próstata Resistentes à Castração/sangue , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Taxa de Sobrevida , Calicreínas Teciduais/genética , Fatores de Transcrição/genética
18.
Genes Dev ; 27(18): 1986-98, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-24065766

RESUMO

More than 50% of patients with chondrosarcomas exhibit gain-of-function mutations in either isocitrate dehydrogenase 1 (IDH1) or IDH2. In this study, we performed genome-wide CpG methylation sequencing of chondrosarcoma biopsies and found that IDH mutations were associated with DNA hypermethylation at CpG islands but not other genomic regions. Regions of CpG island hypermethylation were enriched for genes implicated in stem cell maintenance/differentiation and lineage specification. In murine 10T1/2 mesenchymal progenitor cells, expression of mutant IDH2 led to DNA hypermethylation and an impairment in differentiation that could be reversed by treatment with DNA-hypomethylating agents. Introduction of mutant IDH2 also induced loss of contact inhibition and generated undifferentiated sarcomas in vivo. The oncogenic potential of mutant IDH2 correlated with the ability to produce 2-hydroxyglutarate. Together, these data demonstrate that neomorphic IDH2 mutations can be oncogenic in mesenchymal cells.


Assuntos
Neoplasias Ósseas/enzimologia , Neoplasias Ósseas/genética , Condrossarcoma/enzimologia , Condrossarcoma/genética , Isocitrato Desidrogenase/genética , Isocitrato Desidrogenase/metabolismo , Mutação , Animais , Neoplasias Ósseas/fisiopatologia , Diferenciação Celular , Linhagem Celular , Condrossarcoma/fisiopatologia , Ilhas de CpG/genética , Metilação de DNA , Feminino , Regulação Neoplásica da Expressão Gênica , Genoma , Glutaratos/metabolismo , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/enzimologia , Camundongos , Camundongos Nus , Transplante Heterólogo
19.
Genome Biol ; 14(9): R95, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-24020486

RESUMO

A large number of computational methods have been developed for analyzing differential gene expression in RNA-seq data. We describe a comprehensive evaluation of common methods using the SEQC benchmark dataset and ENCODE data. We consider a number of key features, including normalization, accuracy of differential expression detection and differential expression analysis when one condition has no detectable expression. We find significant differences among the methods, but note that array-based methods adapted to RNA-seq data perform comparably to methods designed for RNA-seq. Our results demonstrate that increasing the number of replicate samples significantly improves detection power over increased sequencing depth.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala/estatística & dados numéricos , Proteínas do Tecido Nervoso/genética , RNA/genética , Análise de Sequência de RNA/estatística & dados numéricos , Software , Química Encefálica , Linhagem Celular , Conjuntos de Dados como Assunto , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Sequência de RNA/métodos , Razão Sinal-Ruído
20.
Clin Cancer Res ; 19(18): 5158-69, 2013 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-23833310

RESUMO

PURPOSE: To investigate the relationship between lactate dehydrogenase A (LDH-A) expression, lactate concentration, cell metabolism, and metastases in murine 4T1 breast tumors. EXPERIMENTAL DESIGN: Inhibition of LDH-A expression and protein levels were achieved in a metastatic breast cancer cell line (4T1) using short hairpin RNA (shRNA) technology. The relationship between tumor LDH-A protein levels and lactate concentration (measured by magnetic resonance spectroscopic imaging, MRSI) and metastases was assessed. RESULTS: LDH-A knockdown cells (KD9) showed a significant reduction in LDH-A protein and LDH activity, less acid production, decreased transwell migration and invasion, lower proliferation, reduced glucose consumption and glycolysis, and increase in oxygen consumption, reactive oxygen species (ROS), and cellular ATP levels, compared with control (NC) cells cultured in 25 mmol/L glucose. In vivo studies showed lower lactate levels in KD9, KD5, and KD317 tumors than in NC or 4T1 wild-type tumors (P < 0.01), and a linear relationship between tumor LDH-A protein expression and lactate concentration. Metastases were delayed and primary tumor growth rate decreased. CONCLUSIONS: We show for the first time that LDH-A knockdown inhibited the formation of metastases, and was accompanied by in vivo changes in tumor cell metabolism. Lactate MRSI can be used as a surrogate to monitor targeted inhibition of LDH-A in a preclinical setting and provides a noninvasive imaging strategy to monitor LDH-A-targeted therapy. This imaging strategy can be translated to the clinic to identify and monitor patients who are at high risk of developing metastatic disease.


Assuntos
Neoplasias da Mama/patologia , L-Lactato Desidrogenase/metabolismo , Ácido Láctico/metabolismo , Neoplasias Pulmonares/secundário , Trifosfato de Adenosina/metabolismo , Animais , Neoplasias da Mama/metabolismo , Adesão Celular , Movimento Celular , Proliferação de Células , Feminino , Glucose/metabolismo , Glicólise , Humanos , Isoenzimas/antagonistas & inibidores , Isoenzimas/genética , Isoenzimas/metabolismo , L-Lactato Desidrogenase/antagonistas & inibidores , L-Lactato Desidrogenase/genética , Lactato Desidrogenase 5 , Neoplasias Pulmonares/metabolismo , Camundongos , Consumo de Oxigênio , RNA Interferente Pequeno/genética , Espécies Reativas de Oxigênio , Células Tumorais Cultivadas
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