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2.
BMC Biol ; 20(1): 117, 2022 05 21.
Artigo em Inglês | MEDLINE | ID: mdl-35597990

RESUMO

BACKGROUND: The APOBEC3 (apolipoprotein B mRNA editing enzyme catalytic polypeptide 3) family of cytidine deaminases is responsible for two mutational signatures (SBS2 and SBS13) found in cancer genomes. APOBEC3 enzymes are activated in response to viral infection, and have been associated with increased mutation burden and TP53 mutation. In addition to this, it has been suggested that APOBEC3 activity may be responsible for mutations that do not fall into the classical APOBEC3 signatures (SBS2 and SBS13), through generation of double strand breaks.Previous work has mainly focused on the effects of APOBEC3 within individual tumour types using exome sequencing data. Here, we use whole genome sequencing data from 2451 primary tumours from 39 different tumour types in the Pan-Cancer Analysis of Whole Genomes (PCAWG) data set to investigate the relationship between APOBEC3 and genomic instability (GI). RESULTS AND CONCLUSIONS: We found that the number of classical APOBEC3 signature mutations correlates with increased mutation burden across different tumour types. In addition, the number of APOBEC3 mutations is a significant predictor for six different measures of GI. Two GI measures (INDELs attributed to INDEL signatures ID6 and ID8) strongly suggest the occurrence and error prone repair of double strand breaks, and the relationship between APOBEC3 mutations and GI remains when SNVs attributed to kataegis are excluded.We provide evidence that supports a model of cancer genome evolution in which APOBEC3 acts as a causative factor in the development of diverse and widespread genomic instability through the generation of double strand breaks. This has important implications for treatment approaches for cancers that carry APOBEC3 mutations, and challenges the view that APOBECs only act opportunistically at sites of single stranded DNA.


Assuntos
Desaminases APOBEC , Neoplasias , Desaminases APOBEC/genética , DNA de Cadeia Simples , Instabilidade Genômica , Humanos , Mutação , Neoplasias/genética
3.
Mol Cancer ; 21(1): 183, 2022 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-36131292

RESUMO

BACKGROUND: Up to 80% of cases of prostate cancer present with multifocal independent tumour lesions leading to the concept of a field effect present in the normal prostate predisposing to cancer development. In the present study we applied Whole Genome DNA Sequencing (WGS) to a group of morphologically normal tissue (n = 51), including benign prostatic hyperplasia (BPH) and non-BPH samples, from men with and men without prostate cancer. We assess whether the observed genetic changes in morphologically normal tissue are linked to the development of cancer in the prostate. RESULTS: Single nucleotide variants (P = 7.0 × 10-03, Wilcoxon rank sum test) and small insertions and deletions (indels, P = 8.7 × 10-06) were significantly higher in morphologically normal samples, including BPH, from men with prostate cancer compared to those without. The presence of subclonal expansions under selective pressure, supported by a high level of mutations, were significantly associated with samples from men with prostate cancer (P = 0.035, Fisher exact test). The clonal cell fraction of normal clones was always higher than the proportion of the prostate estimated as epithelial (P = 5.94 × 10-05, paired Wilcoxon signed rank test) which, along with analysis of primary fibroblasts prepared from BPH specimens, suggests a stromal origin. Constructed phylogenies revealed lineages associated with benign tissue that were completely distinct from adjacent tumour clones, but a common lineage between BPH and non-BPH morphologically normal tissues was often observed. Compared to tumours, normal samples have significantly less single nucleotide variants (P = 3.72 × 10-09, paired Wilcoxon signed rank test), have very few rearrangements and a complete lack of copy number alterations. CONCLUSIONS: Cells within regions of morphologically normal tissue (both BPH and non-BPH) can expand under selective pressure by mechanisms that are distinct from those occurring in adjacent cancer, but that are allied to the presence of cancer. Expansions, which are probably stromal in origin, are characterised by lack of recurrent driver mutations, by almost complete absence of structural variants/copy number alterations, and mutational processes similar to malignant tissue. Our findings have implications for treatment (focal therapy) and early detection approaches.


Assuntos
Hiperplasia Prostática , Neoplasias da Próstata , Células Clonais/patologia , Humanos , Masculino , Nucleotídeos , Próstata/patologia , Hiperplasia Prostática/genética , Hiperplasia Prostática/patologia , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia
4.
Nature ; 520(7547): 353-357, 2015 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-25830880

RESUMO

Cancers emerge from an ongoing Darwinian evolutionary process, often leading to multiple competing subclones within a single primary tumour. This evolutionary process culminates in the formation of metastases, which is the cause of 90% of cancer-related deaths. However, despite its clinical importance, little is known about the principles governing the dissemination of cancer cells to distant organs. Although the hypothesis that each metastasis originates from a single tumour cell is generally supported, recent studies using mouse models of cancer demonstrated the existence of polyclonal seeding from and interclonal cooperation between multiple subclones. Here we sought definitive evidence for the existence of polyclonal seeding in human malignancy and to establish the clonal relationship among different metastases in the context of androgen-deprived metastatic prostate cancer. Using whole-genome sequencing, we characterized multiple metastases arising from prostate tumours in ten patients. Integrated analyses of subclonal architecture revealed the patterns of metastatic spread in unprecedented detail. Metastasis-to-metastasis spread was found to be common, either through de novo monoclonal seeding of daughter metastases or, in five cases, through the transfer of multiple tumour clones between metastatic sites. Lesions affecting tumour suppressor genes usually occur as single events, whereas mutations in genes involved in androgen receptor signalling commonly involve multiple, convergent events in different metastases. Our results elucidate in detail the complex patterns of metastatic spread and further our understanding of the development of resistance to androgen-deprivation therapy in prostate cancer.


Assuntos
Linhagem da Célula , Metástase Neoplásica/patologia , Neoplasias da Próstata/patologia , Androgênios/deficiência , Linhagem da Célula/genética , Células Clonais/metabolismo , Células Clonais/patologia , Análise Mutacional de DNA , Progressão da Doença , Epigênese Genética , Genes Supressores de Tumor , Humanos , Masculino , Metástase Neoplásica/genética , Neoplasias da Próstata/genética , Neoplasias da Próstata/metabolismo , Receptores Androgênicos/metabolismo , Transdução de Sinais/genética
5.
Prostate ; 80(7): 547-558, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32153047

RESUMO

BACKGROUND: Prostate cancer exhibits severe clinical heterogeneity and there is a critical need for clinically implementable tools able to precisely and noninvasively identify patients that can either be safely removed from treatment pathways or those requiring further follow up. Our objectives were to develop a multivariable risk prediction model through the integration of clinical, urine-derived cell-free messenger RNA (cf-RNA) and urine cell DNA methylation data capable of noninvasively detecting significant prostate cancer in biopsy naïve patients. METHODS: Post-digital rectal examination urine samples previously analyzed separately for both cellular methylation and cf-RNA expression within the Movember GAP1 urine biomarker cohort were selected for a fully integrated analysis (n = 207). A robust feature selection framework, based on bootstrap resampling and permutation, was utilized to find the optimal combination of clinical and urinary markers in a random forest model, deemed ExoMeth. Out-of-bag predictions from ExoMeth were used for diagnostic evaluation in men with a clinical suspicion of prostate cancer (PSA ≥ 4 ng/mL, adverse digital rectal examination, age, or lower urinary tract symptoms). RESULTS: As ExoMeth risk score (range, 0-1) increased, the likelihood of high-grade disease being detected on biopsy was significantly greater (odds ratio = 2.04 per 0.1 ExoMeth increase, 95% confidence interval [CI]: 1.78-2.35). On an initial TRUS biopsy, ExoMeth accurately predicted the presence of Gleason score ≥3 + 4, area under the receiver-operator characteristic curve (AUC) = 0.89 (95% CI: 0.84-0.93) and was additionally capable of detecting any cancer on biopsy, AUC = 0.91 (95% CI: 0.87-0.95). Application of ExoMeth provided a net benefit over current standards of care and has the potential to reduce unnecessary biopsies by 66% when a risk threshold of 0.25 is accepted. CONCLUSION: Integration of urinary biomarkers across multiple assay methods has greater diagnostic ability than either method in isolation, providing superior predictive ability of biopsy outcomes. ExoMeth represents a more holistic view of urinary biomarkers and has the potential to result in substantial changes to how patients suspected of harboring prostate cancer are diagnosed.


Assuntos
Ácidos Nucleicos Livres/urina , Metilação de DNA , DNA/urina , Modelos Genéticos , Neoplasias da Próstata/genética , Neoplasias da Próstata/urina , Adulto , Biomarcadores Tumorais/genética , Biomarcadores Tumorais/urina , Ácidos Nucleicos Livres/genética , Estudos de Coortes , DNA/genética , Humanos , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Gradação de Tumores , Neoplasias da Próstata/patologia , Medição de Risco
6.
Br J Cancer ; 122(10): 1467-1476, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32203215

RESUMO

BACKGROUND: Unsupervised learning methods, such as Hierarchical Cluster Analysis, are commonly used for the analysis of genomic platform data. Unfortunately, such approaches ignore the well-documented heterogeneous composition of prostate cancer samples. Our aim is to use more sophisticated analytical approaches to deconvolute the structure of prostate cancer transcriptome data, providing novel clinically actionable information for this disease. METHODS: We apply an unsupervised model called Latent Process Decomposition (LPD), which can handle heterogeneity within individual cancer samples, to genome-wide expression data from eight prostate cancer clinical series, including 1,785 malignant samples with the clinical endpoints of PSA failure and metastasis. RESULTS: We show that PSA failure is correlated with the level of an expression signature called DESNT (HR = 1.52, 95% CI = [1.36, 1.7], P = 9.0 × 10-14, Cox model), and that patients with a majority DESNT signature have an increased metastatic risk (X2 test, P = 0.0017, and P = 0.0019). In addition, we develop a stratification framework that incorporates DESNT and identifies three novel molecular subtypes of prostate cancer. CONCLUSIONS: These results highlight the importance of using more complex approaches for the analysis of genomic data, may assist drug targeting, and have allowed the construction of a nomogram combining DESNT with other clinical factors for use in clinical management.


Assuntos
Biomarcadores Tumorais/sangue , Perfilação da Expressão Gênica/estatística & dados numéricos , Neoplasias da Próstata/genética , Transcriptoma/genética , Regulação Neoplásica da Expressão Gênica/genética , Genômica/estatística & dados numéricos , Humanos , Estimativa de Kaplan-Meier , Masculino , Pessoa de Meia-Idade , Prognóstico , Intervalo Livre de Progressão , Modelos de Riscos Proporcionais , Antígeno Prostático Específico/sangue , Neoplasias da Próstata/sangue , Neoplasias da Próstata/patologia , Medição de Risco , Fatores de Risco
7.
BJU Int ; 124(4): 609-620, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31106513

RESUMO

OBJECTIVES: To develop a risk classifier using urine-derived extracellular vesicle (EV)-RNA capable of providing diagnostic information on disease status prior to biopsy, and prognostic information for men on active surveillance (AS). PATIENTS AND METHODS: Post-digital rectal examination urine-derived EV-RNA expression profiles (n = 535, multiple centres) were interrogated with a curated NanoString panel. A LASSO-based continuation ratio model was built to generate four prostate urine risk (PUR) signatures for predicting the probability of normal tissue (PUR-1), D'Amico low-risk (PUR-2), intermediate-risk (PUR-3), and high-risk (PUR-4) prostate cancer. This model was applied to a test cohort (n = 177) for diagnostic evaluation, and to an AS sub-cohort (n = 87) for prognostic evaluation. RESULTS: Each PUR signature was significantly associated with its corresponding clinical category (P < 0.001). PUR-4 status predicted the presence of clinically significant intermediate- or high-risk disease (area under the curve = 0.77, 95% confidence interval [CI] 0.70-0.84). Application of PUR provided a net benefit over current clinical practice. In an AS sub-cohort (n = 87), groups defined by PUR status and proportion of PUR-4 had a significant association with time to progression (interquartile range hazard ratio [HR] 2.86, 95% CI 1.83-4.47; P < 0.001). PUR-4, when used continuously, dichotomized patient groups with differential progression rates of 10% and 60% 5 years after urine collection (HR 8.23, 95% CI 3.26-20.81; P < 0.001). CONCLUSION: Urine-derived EV-RNA can provide diagnostic information on aggressive prostate cancer prior to biopsy, and prognostic information for men on AS. PUR represents a new and versatile biomarker that could result in substantial alterations to current treatment of patients with prostate cancer.

8.
Hum Mol Genet ; 25(24): 5490-5499, 2016 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-27798103

RESUMO

Molecular and epidemiological differences have been described between TMPRSS2:ERG fusion-positive and fusion-negative prostate cancer (PrCa). Assuming two molecularly distinct subtypes, we have examined 27 common PrCa risk variants, previously identified in genome-wide association studies, for subtype specific associations in a total of 1221 TMPRSS2:ERG phenotyped PrCa cases. In meta-analyses of a discovery set of 552 cases with TMPRSS2:ERG data and 7650 unaffected men from five centers we have found support for the hypothesis that several common risk variants are associated with one particular subtype rather than with PrCa in general. Risk variants were analyzed in case-case comparisons (296 TMPRSS2:ERG fusion-positive versus 256 fusion-negative cases) and an independent set of 669 cases with TMPRSS2:ERG data was established to replicate the top five candidates. Significant differences (P < 0.00185) between the two subtypes were observed for rs16901979 (8q24) and rs1859962 (17q24), which were enriched in TMPRSS2:ERG fusion-negative (OR = 0.53, P = 0.0007) and TMPRSS2:ERG fusion-positive PrCa (OR = 1.30, P = 0.0016), respectively. Expression quantitative trait locus analysis was performed to investigate mechanistic links between risk variants, fusion status and target gene mRNA levels. For rs1859962 at 17q24, genotype dependent expression was observed for the candidate target gene SOX9 in TMPRSS2:ERG fusion-positive PrCa, which was not evident in TMPRSS2:ERG negative tumors. The present study established evidence for the first two common PrCa risk variants differentially associated with TMPRSS2:ERG fusion status. TMPRSS2:ERG phenotyping of larger studies is required to determine comprehensive sets of variants with subtype-specific roles in PrCa.


Assuntos
Proteínas de Fusão Oncogênica/genética , Neoplasias da Próstata/genética , Serina Endopeptidases/genética , Regulação Neoplásica da Expressão Gênica/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Genótipo , Humanos , Hibridização in Situ Fluorescente , Masculino , Neoplasias da Próstata/patologia , Locos de Características Quantitativas/genética , Regulador Transcricional ERG/genética
9.
Genome Res ; 25(6): 814-24, 2015 06.
Artigo em Inglês | MEDLINE | ID: mdl-25963125

RESUMO

Mitochondrial genomes are separated from the nuclear genome for most of the cell cycle by the nuclear double membrane, intervening cytoplasm, and the mitochondrial double membrane. Despite these physical barriers, we show that somatically acquired mitochondrial-nuclear genome fusion sequences are present in cancer cells. Most occur in conjunction with intranuclear genomic rearrangements, and the features of the fusion fragments indicate that nonhomologous end joining and/or replication-dependent DNA double-strand break repair are the dominant mechanisms involved. Remarkably, mitochondrial-nuclear genome fusions occur at a similar rate per base pair of DNA as interchromosomal nuclear rearrangements, indicating the presence of a high frequency of contact between mitochondrial and nuclear DNA in some somatic cells. Transmission of mitochondrial DNA to the nuclear genome occurs in neoplastically transformed cells, but we do not exclude the possibility that some mitochondrial-nuclear DNA fusions observed in cancer occurred years earlier in normal somatic cells.


Assuntos
DNA Mitocondrial/genética , Genoma Humano , Genoma Mitocondrial/genética , Neoplasias/genética , Sequência de Aminoácidos , Linhagem Celular Tumoral , Núcleo Celular/genética , Cromossomos/genética , Variações do Número de Cópias de DNA , Reparo do DNA por Junção de Extremidades , Replicação do DNA , Células HeLa , Humanos , Hibridização in Situ Fluorescente , Mitocôndrias/genética , Dados de Sequência Molecular , Reprodutibilidade dos Testes , Análise de Sequência de DNA
10.
J Orthop Traumatol ; 19(1): 12, 2018 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-30132086

RESUMO

BACKGROUND: Limited data exists in analyzing open reduction and internal fixation (ORIF) and arthroplasty in the management of open proximal humerus fractures. We analyzed differences in hospital course between these procedures, patient demographics, complication rate, length of stay, hospital charges, and mortality rate. MATERIALS AND METHODS: This is a retrospective review of the Nationwide Inpatient Sample database. ICD-9 codes identified patients hospitalized for open proximal humerus fractures from 1998 to 2013 who underwent ORIF or shoulder arthroplasty (hemi-, total, or reverse). Demographics and in-hospital complications were compared. Logistic regression controlling for age, gender, and Deyo index tested the impact of ORIF vs ARTH on any complications. RESULTS: Seven hundred thirty patients were included (ORIF, n = 662 vs ARTH, n = 68). ORIF patients were younger (p < 0.001), more likely to be males (p < 0.001), and had a lower Deyo score (p = 0.012). Both groups had comparable complication rates (21.4% vs 18.0%, p = 0.535), lengths of stay (7.86 days vs 7.44 days, p = 0.833), hospital charges ($76,998 vs $64,133, p = 0.360), and mortality rates (0.2% vs 0%, p = 0.761). Type of surgery was not a predictor of any complications (OR = 0.67 [95% CI 0.33-1.35], p = 0.266), extended length of stay (OR = 1.01 [95% CI 0.58-1.78], p = 0.967), or high hospital charges (OR = 1.39 [95% CI 0.68-2.86], p = 0.366). CONCLUSION: We revealed no differences in hospital course between ORIF and arthroplasty for management of open proximal humerus fractures. Although differences in demographics existed, no differences in complication rates, length of stay, hospital charges and mortality rates were noted. Future studies can evaluate the long-term outcomes of these procedures. LEVEL OF EVIDENCE: Level III.


Assuntos
Artroplastia/métodos , Fixação Interna de Fraturas/métodos , Fraturas Expostas/cirurgia , Fraturas do Úmero/cirurgia , Úmero/cirurgia , Pacientes Internados/estatística & dados numéricos , Bases de Dados Factuais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos
11.
Prostate ; 77(9): 990-999, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28419548

RESUMO

BACKGROUND: The measurement of gene expression in post-digital rectal examination (DRE) urine specimens provides a non-invasive method to determine a patient's risk of prostate cancer. Many currently available assays use whole urine or cell pellets for the analysis of prostate cancer-associated genes, although the use of extracellular vesicles (EVs) has also recently been of interest. We investigated the expression of prostate-, kidney-, and bladder-specific transcripts and known prostate cancer biomarkers in urine EVs. METHODS: Cell pellets and EVs were recovered from post-DRE urine specimens, with the total RNA yield and quality determined by Bioanalyzer. The levels of prostate, kidney, and bladder-associated transcripts in EVs were assessed by TaqMan qPCR and targeted sequencing. RESULTS: RNA was more consistently recovered from the urine EV specimens, with over 80% of the patients demonstrating higher RNA yields in the EV fraction as compared to urine cell pellets. The median EV RNA yield of 36.4 ng was significantly higher than the median urine cell pellet RNA yield of 4.8 ng. Analysis of the post-DRE urine EVs indicated that prostate-specific transcripts were more abundant than kidney- or bladder-specific transcripts. Additionally, patients with prostate cancer had significantly higher levels of the prostate cancer-associated genes PCA3 and ERG. CONCLUSIONS: Post-DRE urine EVs are a viable source of prostate-derived RNAs for biomarker discovery and prostate cancer status can be distinguished from analysis of these specimens. Continued analysis of urine EVs offers the potential discovery of novel biomarkers for pre-biopsy prostate cancer detection.


Assuntos
Antígenos de Neoplasias , Exame Retal Digital/métodos , Vesículas Extracelulares , Próstata , Neoplasias da Próstata , Urinálise/métodos , Adulto , Idoso , Antígenos de Neoplasias/genética , Antígenos de Neoplasias/urina , Biomarcadores Tumorais/urina , Detecção Precoce de Câncer/métodos , Vesículas Extracelulares/metabolismo , Vesículas Extracelulares/patologia , Perfilação da Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Próstata/metabolismo , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/urina , Reprodutibilidade dos Testes , Regulador Transcricional ERG/genética , Regulador Transcricional ERG/urina
12.
Breast Cancer Res Treat ; 165(3): 531-543, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28695300

RESUMO

PURPOSE: Combining molecular therapies with chemotherapy may offer an improved clinical outcome for chemoresistant tumours. Sphingosine-1-phosphate (S1P) receptor antagonist and sphingosine kinase 1 (SK1) inhibitor FTY720 (FTY) has promising anticancer properties, however, it causes systemic lymphopenia which impairs its use in cancer patients. In this study, we developed a nanoparticle (NP) combining docetaxel (DTX) and FTY for enhanced anticancer effect, targeted tumour delivery and reduced systemic toxicity. METHODS: Docetaxel, FTY and glucosamine were covalently conjugated to poly(lactic-co-glycolic acid) (PLGA). NPs were characterised by dynamic light scattering and electron microscopy. The cellular uptake, cytotoxicity and in vivo antitumor efficacy of CNPs were evaluated. RESULTS: We show for the first time that in triple negative breast cancer cells FTY provides chemosensitisation to DTX, allowing a four-fold reduction in the effective dose. We have encapsulated both drugs in PLGA complex NPs (CNPs), with narrow size distribution of ~ 100 nm and excellent cancer cell uptake providing sequential, sustained release of FTY and DTX. In triple negative breast cancer cells and mouse breast cancer models, CNPs had similar efficacy to systemic free therapies, but allowed an effective drug dose reduction. Application of CNPs has significantly reversed chemotherapy side effects such as weight loss, liver toxicity and, most notably, lymphopenia. CONCLUSIONS: We show for the first time the DTX chemosensitising effects of FTY in triple negative breast cancer. We further demonstrate that encapsulation of free drugs in CNPs can improve targeting, provide low off-target toxicity and most importantly reduce FTY-induced lymphopenia, offering potential therapeutic use of FTY in clinical cancer treatment.


Assuntos
Neoplasias da Mama/complicações , Neoplasias da Mama/patologia , Cloridrato de Fingolimode/administração & dosagem , Linfopenia/induzido quimicamente , Nanopartículas , Taxoides/administração & dosagem , Animais , Neoplasias da Mama/tratamento farmacológico , Linhagem Celular Tumoral , Modelos Animais de Doenças , Docetaxel , Feminino , Cloridrato de Fingolimode/efeitos adversos , Humanos , Camundongos , Metástase Neoplásica , Estadiamento de Neoplasias , Carga Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto
13.
BJU Int ; 117(4): 686-96, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26471473

RESUMO

OBJECTIVES: To evaluate the immunocytochemical detection of ERG protein in exfoliated cells as a means of identifying patients with prostate cancer (PCa) before prostate biopsy. MATERIALS AND METHODS: Urine samples (30 mL) were collected after digital rectal examination (DRE) from 159 patients with an elevated age-specific prostate-specific antigen (PSA) and/or an abnormal DRE who underwent prostate biopsy. In all cases, exfoliated urinary cells from half of the urine sample underwent immunocytochemical assessment for ERG protein expression. Exfoliated cells in the remaining half underwent assessment of TMPRSS2:ERG status using either nested reverse-transcriptase (RT)-PCR (151 cases) or fluorescence in situ hybridization (FISH; eight cases). Corresponding tissue samples were evaluated using FISH to determine chromosomal gene fusion tissue status and immunohistochemistry (IHC) to determine ERG protein expression. Results were correlated with clinicopathological variables. RESULTS: The sensitivity and specificity of urinary ERG immunocytochemistry (ICC) for PCa were 22.7 and 100%, respectively. ERG ICC results correlated with advanced tumour grade, stage and higher serum PSA. In comparison, urine TMPRSS2:ERG transcript analysis had 27% sensitivity and 98% specificity for PCa detection. On tissue IHC, ERG staining was highly specific for PCa. In all, 52% of cancers harboured foci of ERG staining; however, only 46% of cancers that were found to have ERG overexpression were positive on urine ICC. The ERG ICC results showed strong concordance with urinary RT-PCR and FISH, and tissue IHC and FISH. CONCLUSION: This is the first study to show that cytological gene fusion detection using ICC is feasible and identifies patients with adverse disease markers. ERG ICC was highly specific, but this technique was less sensitive than RT-PCR.


Assuntos
Adenocarcinoma/diagnóstico , Próstata/patologia , Neoplasias da Próstata/diagnóstico , Neoplasias da Próstata/patologia , Transativadores/metabolismo , Biópsia com Agulha de Grande Calibre , Detecção Precoce de Câncer , Humanos , Imuno-Histoquímica , Hibridização in Situ Fluorescente , Masculino , Antígeno Prostático Específico/metabolismo , Neoplasias da Próstata/urina , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Serina Endopeptidases/metabolismo , Regulador Transcricional ERG
14.
Breast Cancer Res Treat ; 149(1): 59-67, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25481644

RESUMO

Obesity is a known risk factor for breast cancer. We have recently identified that adipokine leptin regulates the expression of a proto-oncogenic enzyme sphingosine kinase 1 (SK1). Signal transducer and activator of transcription 3 (STAT3) has been linked to breast cancer progression and here we investigate the mechanism of leptin-induced STAT3 activation in ER-negative breast cancer. Gene and protein expression in human primary and secondary breast cancer tissues was analysed using quantitative real-time polymerase chain reaction (qRT-PCR) assay and immunofluorescence. Leptin-induced signalling was analysed in human ER-negative breast cancer cells using Western blotting, qRT-PCR and radiolabelling assays. Gene expression and receptor signalling was modified using small interfering RNA and neutralising antibodies. In human ER-negative breast tumours and lymph node metastases, the expression of leptin receptor significantly correlated with SK1. In ER-negative breast cancer cells, SK1 knockdown led to a significant reduction in leptin-induced STAT3 phosphorylation. Knockdown of another known activator of STAT3 signalling, gp130 also resulted in a significant decrease in leptin-induced STAT3 phosphorylation. ELISA assay showed that leptin produces a significant amount of IL-6 in an SK1-dependent manner. IL-6 neutralising antibodies significantly reduced p-STAT3. Immunofluorescent staining of human primary and secondary breast tumours showed significant correlation between SK1 and IL-6 (P < 0.001), SK1 and p-STAT3 (P < 0.01) and IL-6 and p-STAT3 (P < 0.01). Our findings demonstrate that leptin-induced STAT3 is partially cross activated through SK1-mediated IL6 secretion and gp130 activation. Positive correlations in human tissues suggest the potential significance of this pathway in ER-negative breast cancer.


Assuntos
Neoplasias da Mama/genética , Receptor gp130 de Citocina/biossíntese , Interleucina-6/biossíntese , Leptina/genética , Fosfotransferases (Aceptor do Grupo Álcool)/biossíntese , Fator de Transcrição STAT3/biossíntese , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Interleucina-6/genética , Metástase Linfática , Fosforilação , Fosfotransferases (Aceptor do Grupo Álcool)/genética , Receptores de Estrogênio/genética , Receptores para Leptina/genética , Fator de Transcrição STAT3/genética , Transdução de Sinais , Ativação Transcricional/genética
15.
Adv Exp Med Biol ; 883: 295-315, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26621474

RESUMO

Surface polysaccharides are an often essential component of the outer surface of bacteria. They may serve to protect organisms from harsh environmental conditions and to increase virulence. The focus of this review will be to introduce polysaccharide biosynthesis and export from the cell, and the associated techniques used to determine these glycostructures. Protein interactions and proteomics will then be discussed while introducing systems biology approaches used to determine protein-protein and protein-polysaccharide interactions. The final section will address related screening methods used to study gene regulation in bacteria relating to polysaccharide gene clusters and their associated regulators. The goal of this review will be to highlight key studies that have increased our knowledge of glycobiology and discuss novel methods that examine this field at the cellular level using systems biology.


Assuntos
Polissacarídeos Bacterianos/química , Biologia de Sistemas , Glicosiltransferases , Polissacarídeos Bacterianos/biossíntese , Polissacarídeos Bacterianos/genética , Análise de Sequência de RNA , Técnicas do Sistema de Duplo-Híbrido
16.
Lancet Oncol ; 15(13): 1521-1532, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25456371

RESUMO

BACKGROUND: Clinical prognostic groupings for localised prostate cancers are imprecise, with 30-50% of patients recurring after image-guided radiotherapy or radical prostatectomy. We aimed to test combined genomic and microenvironmental indices in prostate cancer to improve risk stratification and complement clinical prognostic factors. METHODS: We used DNA-based indices alone or in combination with intra-prostatic hypoxia measurements to develop four prognostic indices in 126 low-risk to intermediate-risk patients (Toronto cohort) who will receive image-guided radiotherapy. We validated these indices in two independent cohorts of 154 (Memorial Sloan Kettering Cancer Center cohort [MSKCC] cohort) and 117 (Cambridge cohort) radical prostatectomy specimens from low-risk to high-risk patients. We applied unsupervised and supervised machine learning techniques to the copy-number profiles of 126 pre-image-guided radiotherapy diagnostic biopsies to develop prognostic signatures. Our primary endpoint was the development of a set of prognostic measures capable of stratifying patients for risk of biochemical relapse 5 years after primary treatment. FINDINGS: Biochemical relapse was associated with indices of tumour hypoxia, genomic instability, and genomic subtypes based on multivariate analyses. We identified four genomic subtypes for prostate cancer, which had different 5-year biochemical relapse-free survival. Genomic instability is prognostic for relapse in both image-guided radiotherapy (multivariate analysis hazard ratio [HR] 4·5 [95% CI 2·1-9·8]; p=0·00013; area under the receiver operator curve [AUC] 0·70 [95% CI 0·65-0·76]) and radical prostatectomy (4·0 [1·6-9·7]; p=0·0024; AUC 0·57 [0·52-0·61]) patients with prostate cancer, and its effect is magnified by intratumoral hypoxia (3·8 [1·2-12]; p=0·019; AUC 0·67 [0·61-0·73]). A novel 100-loci DNA signature accurately classified treatment outcome in the MSKCC low-risk to intermediate-risk cohort (multivariate analysis HR 6·1 [95% CI 2·0-19]; p=0·0015; AUC 0·74 [95% CI 0·65-0·83]). In the independent MSKCC and Cambridge cohorts, this signature identified low-risk to high-risk patients who were most likely to fail treatment within 18 months (combined cohorts multivariate analysis HR 2·9 [95% CI 1·4-6·0]; p=0·0039; AUC 0·68 [95% CI 0·63-0·73]), and was better at predicting biochemical relapse than 23 previously published RNA signatures. INTERPRETATION: This is the first study of cancer outcome to integrate DNA-based and microenvironment-based failure indices to predict patient outcome. Patients exhibiting these aggressive features after biopsy should be entered into treatment intensification trials. FUNDING: Movember Foundation, Prostate Cancer Canada, Ontario Institute for Cancer Research, Canadian Institute for Health Research, NIHR Cambridge Biomedical Research Centre, The University of Cambridge, Cancer Research UK, Cambridge Cancer Charity, Prostate Cancer UK, Hutchison Whampoa Limited, Terry Fox Research Institute, Princess Margaret Cancer Centre Foundation, PMH-Radiation Medicine Program Academic Enrichment Fund, Motorcycle Ride for Dad (Durham), Canadian Cancer Society.


Assuntos
Biomarcadores Tumorais/genética , Perfilação da Expressão Gênica , Recidiva Local de Neoplasia/diagnóstico , Recidiva Local de Neoplasia/genética , Neoplasias da Próstata/genética , Microambiente Tumoral/genética , DNA de Neoplasias/genética , Seguimentos , Genômica , Humanos , Masculino , Análise de Sequência com Séries de Oligonucleotídeos , Prognóstico , Estudos Retrospectivos , Fatores de Tempo
17.
BMC Genomics ; 15: 880, 2014 Oct 08.
Artigo em Inglês | MEDLINE | ID: mdl-25297811

RESUMO

BACKGROUND: Gene expression changes induced by carcinogens may identify differences in molecular function between target and non-target organs. Target organs for benzo[a]pyrene (BaP) carcinogenicity in mice (lung, spleen and forestomach) and three non-target organs (liver, colon and glandular stomach) were investigated for DNA adducts by 32P-postlabelling, for gene expression changes by cDNA microarray and for miRNA expression changes by miRNA microarray after exposure of animals to BaP. RESULTS: BaP-DNA adduct formation occurred in all six organs at levels that did not distinguish between target and non-target. cDNA microarray analysis showed a variety of genes modulated significantly by BaP in the six organs and the overall gene expression patterns were tissue specific. Gene ontology analysis also revealed that BaP-induced bioactivities were tissue specific; eight genes (Tubb5, Fos, Cdh1, Cyp1a1, Apc, Myc, Ctnnb1 and Cav) showed significant expression difference between three target and three non-target organs. Additionally, several gene expression changes, such as in Trp53 activation and Stat3 activity suggested some similarities in molecular mechanisms in two target organs (lung and spleen), which were not found in the other four organs. Changes in miRNA expression were generally tissue specific, involving, in total, 21/54 miRNAs significantly up- or down-regulated. CONCLUSIONS: Altogether, these findings showed that DNA adduct levels and early gene expression changes did not fully distinguish target from non-target organs. However, mechanisms related to early changes in p53, Stat3 and Wnt/ß-catenin pathways may play roles in defining BaP organotropism.


Assuntos
Benzo(a)pireno/farmacologia , Adutos de DNA/análise , Dano ao DNA/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Animais , Benzo(a)pireno/análise , Carcinogênese , Feminino , Redes Reguladoras de Genes , Masculino , Camundongos , Camundongos Endogâmicos BALB C , MicroRNAs/metabolismo , Análise de Sequência com Séries de Oligonucleotídeos , Fator de Transcrição STAT3/genética , Fator de Transcrição STAT3/metabolismo , Transcriptoma , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
19.
PLoS Pathog ; 8(6): e1002773, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22761574

RESUMO

Bacterial pathogens often manipulate host immune pathways to establish acute and chronic infection. Many Gram-negative bacteria do this by secreting effector proteins through a type III secretion system that alter the host response to the pathogen. In this study, we determined that the phage-encoded GogB effector protein in Salmonella targets the host SCF E3 type ubiquitin ligase through an interaction with Skp1 and the human F-box only 22 (FBXO22) protein. Domain mapping and functional knockdown studies indicated that GogB-containing bacteria inhibited IκB degradation and NFκB activation in macrophages, which required Skp1 and a eukaryotic-like F-box motif in the C-terminal domain of GogB. GogB-deficient Salmonella were unable to limit NFκB activation, which lead to increased proinflammatory responses in infected mice accompanied by extensive tissue damage and enhanced colonization in the gut during long-term chronic infections. We conclude that GogB is an anti-inflammatory effector that helps regulate inflammation-enhanced colonization by limiting tissue damage during infection.


Assuntos
Proteínas de Bactérias/metabolismo , Proteínas F-Box/metabolismo , Interações Hospedeiro-Parasita/imunologia , Receptores Citoplasmáticos e Nucleares/metabolismo , Proteínas Quinases Associadas a Fase S/metabolismo , Infecções por Salmonella/metabolismo , Animais , Proteínas de Bactérias/imunologia , Western Blotting , Proteínas F-Box/imunologia , Feminino , Técnicas de Silenciamento de Genes , Transferência Genética Horizontal , Humanos , Imunoprecipitação , Camundongos , Camundongos Endogâmicos C57BL , NF-kappa B/imunologia , NF-kappa B/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Receptores Citoplasmáticos e Nucleares/imunologia , Proteínas Quinases Associadas a Fase S/imunologia , Infecções por Salmonella/imunologia
20.
Nat Genet ; 37(6): 590-2, 2005 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15908952

RESUMO

We examined the coding sequence of 518 protein kinases, approximately 1.3 Mb of DNA per sample, in 25 breast cancers. In many tumors, we detected no somatic mutations. But a few had numerous somatic mutations with distinctive patterns indicative of either a mutator phenotype or a past exposure.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Mutação , Proteínas Quinases/genética , Idoso , Análise Mutacional de DNA , Feminino , Humanos , Família Multigênica
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