RESUMEN
BACKGROUND: Current diagnostic tools are unable to distinguish low-grade indolent prostate cancer (PrCa) from that with a propensity to become metastatic and/or lethal. Recent evidence suggests that reprogramming of the transcriptome may drive the metastatic phenotype, and that this reprogramming is controlled, at least in part, by epigenetic changes to the DNA of cancer cells, including methylation. These changes, referred to as 'epigenetic drivers,' have previously been associated with cancer cell survival. METHODS: Here, using Illumina Methylation EPIC array data of paired primary PrCa and metastatic bone samples, we identified WNT5A as a putative epi-driver of PrCa metastasis to the bone, which was further validated in vitro. RESULTS: Significantly higher WNT5A methylation was observed in primary PrCa samples and 22Rv1 cells compared to metastatic bone samples and PC-3 cells. This higher methylation was associated with significantly lower WNT5A gene expression. CONCLUSION: Given the limited effective therapies available for metastatic cancer sufferers, particularly those whose disease has metastasised to the bone, WNT5A presents as a potential putative target for therapy.
Asunto(s)
Neoplasias Óseas , Metilación de ADN , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Neoplasias de la Próstata , Proteína Wnt-5a , Humanos , Proteína Wnt-5a/metabolismo , Proteína Wnt-5a/genética , Masculino , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/metabolismo , Neoplasias Óseas/secundario , Neoplasias Óseas/genética , Neoplasias Óseas/metabolismo , Línea Celular Tumoral , AncianoRESUMEN
Recurrent tumor copy number variations (CNVs) in prostate cancer (PrCa) have predominantly been discovered in sporadic tumor cohorts. Here, we examined familial prostate tumors for novel CNVs as prior studies suggest these harbor distinct CNVs. Array comparative genomic hybridization of 12 tumors from an Australian PrCa family, PcTas9, highlighted multiple recurrent CNVs, including amplification of EEF2 (19p13.3) in 100% of tumors. The EEF2 CNV was examined in a further 26 familial and seven sporadic tumors from the Australian cohort and in 494 tumors unselected for family history from The Cancer Genome Atlas (TCGA). EEF2 overexpression was observed in seven PcTas9 tumors, in addition to seven other predominantly familial tumors (ntotal = 34%). EEF2 amplification was only observed in 1.4% of TCGA tumors, however 7.5% harbored an EEF2 deletion. Analysis of genes co-expressed with EEF2 revealed significant upregulation of two genes, ZNF74 and ADSL, and downregulation of PLSCR1 in both EEF2 amplified familial tumors and EEF2 deleted TCGA tumors. Furthermore, in TCGA tumors, EEF2 amplification and deletion were significantly associated with a higher Gleason score. In summary, we identified a novel PrCa CNV that was predominantly amplified in familial tumors and deleted in unselected tumors. Our results provide further evidence that familial tumors harbor distinct CNVs, potentially due to an inherited predisposition, but also suggest that regardless of how EEF2 is dysregulated, a similar set of genes involved in key cancer pathways are impacted. Given the current lack of gene-based biomarkers and clinical targets in PrCa, further investigation of EEF2 is warranted.
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Síndromes Neoplásicos Hereditarios , Neoplasias de la Próstata , Humanos , Masculino , Australia , Hibridación Genómica Comparativa , Variaciones en el Número de Copia de ADN , Amplificación de Genes , Recurrencia Local de Neoplasia/genética , Síndromes Neoplásicos Hereditarios/genética , Neoplasias de la Próstata/genética , Factores de Elongación de Péptidos/genéticaRESUMEN
There is strong interest in the characterisation of gene fusions and their use to enhance clinical practices in prostate cancer (PrCa). Significantly, ~50% of prostate tumours harbour a gene fusion. Inherited factors are thought to predispose to these events but, to date, only one study has investigated gene fusions in a familial context. Here, we examined the prevalence and diversity of gene fusions in 14 tumours from a single large PrCa family, PcTas9, using the TruSight® RNA Fusion Panel and Sanger sequencing validation. These fusions were then explored in The Cancer Genome Atlas (TCGA) PrCa data set (n = 494). Overall, 64.3% of PcTas9 tumours harboured a gene fusion, including known erythroblast transformation-specific (ETS) fusions involving ERG and ETV1, and two novel gene fusions, C19orf48:ETV4 and RYBP:FOXP1. Although 3' ETS genes were overexpressed in PcTas9 and TCGA tumour samples, 3' fusion of FOXP1 did not appear to alter its expression. In addition, PcTas9 fusion carriers were more likely to have lower-grade disease than noncarriers (p = 0.02). Likewise, TCGA tumours with high-grade disease were less likely to harbour fusions (p = 0.03). Our study further implicates an inherited predisposition to PrCa gene fusion events, which are associated with less aggressive tumours. This knowledge could lead to clinical strategies to predict men at risk for fusion-positive PrCa and, thus, identify patients who are more or less at risk of aggressive disease and/or responsive to particular therapies.
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Proteínas de Unión al ADN , Neoplasias de la Próstata , Proteínas de Unión al ADN/genética , Factores de Transcripción Forkhead/genética , Fusión Génica , Predisposición Genética a la Enfermedad , Humanos , Masculino , Proteínas de Fusión Oncogénica/genética , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Proteínas Represoras/genética , Factores de Transcripción/genéticaAsunto(s)
Proteínas de Unión al ADN/genética , Predisposición Genética a la Enfermedad/genética , Neoplasias de la Próstata/genética , Femenino , Estudio de Asociación del Genoma Completo , Genotipo , Heterocigoto , Secuenciación de Nucleótidos de Alto Rendimiento , Humanos , Masculino , Mutación/genética , Linaje , Análisis de Secuencia de ADNRESUMEN
Prostate cancer (PrCa) is highly heritable, and although rare variants contribute significantly to PrCa risk, few have been identified to date. Herein, whole-genome sequencing was performed in a large PrCa family featuring multiple affected relatives spanning several generations. A rare, predicted splice site EZH2 variant, rs78589034 (G > A), was identified as segregating with disease in all but two individuals in the family, one of whom was affected with lymphoma and bowel cancer and a female relative. This variant was significantly associated with disease risk in combined familial and sporadic PrCa datasets (n = 1551; odds ratio [OR] = 3.55, P = 1.20 × 10-5 ). Transcriptome analysis was performed on prostate tumour needle biopsies available for two rare variant carriers and two wild-type cases. Although no allele-dependent differences were detected in EZH2 transcripts, a distinct differential gene expression signature was observed when comparing prostate tissue from the rare variant carriers with the wild-type samples. The gene expression signature comprised known downstream targets of EZH2 and included the top-ranked genes, DUSP1, FOS, JUNB and EGR1, which were subsequently validated by qPCR. These data provide evidence that rs78589034 is associated with increased PrCa risk in Tasmanian men and further, that this variant may be associated with perturbed EZH2 function in prostate tissue. Disrupted EZH2 function is a driver of tumourigenesis in several cancers, including prostate, and is of significant interest as a therapeutic target.
Asunto(s)
Biomarcadores de Tumor/genética , Proteína Potenciadora del Homólogo Zeste 2/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Neoplasias de la Próstata/epidemiología , Transcriptoma , Anciano , Anciano de 80 o más Años , Estudios de Seguimiento , Regulación Neoplásica de la Expresión Génica , Humanos , Masculino , Persona de Mediana Edad , Pronóstico , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Factores de Riesgo , Tasmania/epidemiología , Células Tumorales Cultivadas , Estados Unidos/epidemiologíaRESUMEN
BACKGROUND: Examination of epigenetic changes at the ITGB4 gene promoter reveals altered methylation at different stages of prostate tumour progression and these changes may, in part, explain the complex patterns of gene expression of this integrin observed. Transcriptional re-programming perturbs expression of cell adhesion molecules and underpins metastatic tumour cell behaviour. Decreasing expression of the cell adhesion molecule ITGB4, which encodes the beta subunit of the integrin, alpha6 beta4 (α6ß4), has been correlated with increased tumour aggressiveness and metastasis in multiple tumour types including prostate cancer. Paradoxically, in vitro studies in tumour cell models demonstrate that ITGB4 mediates cell mobility and invasion. Herein we examined whether transcriptional re-programming by methylation influenced ITGB4 gene expression at different stages of prostate cancer progression. Bisulphite sequencing of a large CpG island in the ITGB4 gene promoter identified differentially methylated regions in prostate cancer cell lines representing a localised tumour (22Rv1), lymph node metastasis (LNCaP), and a bone metastasis (PC-3). The highest levels of methylation were observed in the CpG island surrounding the ITGB4 transcription start site in PC-3 cells, and this observation also correlated with higher gene expression of ITGB4 in these cells. Furthermore, PC-3 cells expressed two distinct transcripts, using an alternate transcription start site, which was not detected in other cell lines. In prostate tumour biopsy samples, patterns of methylation across the ITGB4 promoter were similar overall in matched primary and metastatic samples (n = 4 pairs), with a trend toward loss of methylation at specific sites in metastatic lesions.
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Metilación de ADN , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Integrina beta4/genética , Regiones Promotoras Genéticas , Neoplasias de la Próstata/genética , Neoplasias de la Próstata/patología , Apoptosis , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Proliferación Celular , Islas de CpG , Humanos , Integrina beta4/metabolismo , Masculino , Células Tumorales CultivadasRESUMEN
Introduction: Various pressures exist for curricular change, including economic forces, burgeoning knowledge, broadening learning outcomes, and improving quality and outcomes of learning experiences. In an Australian 5-year undergraduate medical course, staff were asked to reduce teaching hours by 20% to alleviate perceived overcrowded preclinical curriculum, achieve operating efficiencies and liberate time for students' self-directed learning.Methods: A case study design with mixed methods was used to evaluate outcomes.Results: Teaching hours were reduced by 198 hours (14%) overall, lectures by 153 hours (19%) and other learning activities by 45 hours (7%). Summative assessment scores did not change significantly after the reductions: 0.4% increase, 1.5% decrease and 1.7% increase in Years 1, 2 and 3, respectively. The percentage of students successfully completing their academic year did not change significantly: 94.4% before and 93.3% after the reductions. Student evaluations from eVALUate surveys changed little, except workload was perceived to be more reasonable.Conclusions: Teaching hours, particularly lectures, can be moderately reduced with little impact on student learning outcomes or satisfaction with an undergraduate medical course.
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Educación de Pregrado en Medicina/métodos , Docentes Médicos/estadística & datos numéricos , Aprendizaje , Admisión y Programación de Personal/estadística & datos numéricos , Actitud del Personal de Salud , Australia , Humanos , Estudios de Casos Organizacionales , Estudiantes de Medicina/psicología , Encuestas y Cuestionarios , Carga de TrabajoRESUMEN
The HOXB13 G84E variant is associated with risk of prostate cancer (PCa), however the role this variant plays in PCa development is unknown. This study examined 751 cases, 450 relatives and 355 controls to determine the contribution of this variant to PCa risk in Tasmania and investigated HOXB13 gene and protein expression in tumours from nine G84E heterozygote variant and 13 wild-type carriers. Quantitative PCR and immunohistochemistry showed that HOXB13 gene and protein expression did not differ between tumour samples from variant and wild-type carriers. Allele-specific transcription revealed that two of seven G84E carriers transcribed both the variant and wild-type allele, while five carriers transcribed the wild-type allele. Methylation of surrounding CpG sites was lower in the variant compared to the wild-type allele, however overall methylation across the region was very low. Notably, tumour characteristics were less aggressive in the two variant carriers that transcribed the variant allele compared to the five that did not. This study has shown that HOXB13 expression does not differ between tumour tissue of G84E variant carriers and non-carriers. Intriguingly, the G84E variant allele was rarely transcribed in carriers, suggesting that HOXB13 expression may be driven by the wild-type allele in the majority of carriers.
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Expresión Génica/genética , Predisposición Genética a la Enfermedad/genética , Variación Genética/genética , Proteínas de Homeodominio/genética , Neoplasias de la Próstata/genética , Alelos , Estudios de Casos y Controles , Estudios de Cohortes , Metilación de ADN/genética , Formaldehído/farmacología , Genotipo , Heterocigoto , Humanos , Masculino , Adhesión en Parafina/métodos , Factores de Riesgo , Tasmania , Transcripción Genética/genéticaRESUMEN
Devil facial tumour disease (DFTD) is a transmissible cancer devastating the Tasmanian devil (Sarcophilus harrisii) population. The cancer cell is the 'infectious' agent transmitted as an allograft by biting. Animals usually die within a few months with no evidence of antibody or immune cell responses against the DFTD allograft. This lack of anti-tumour immunity is attributed to an absence of cell surface major histocompatibility complex (MHC)-I molecule expression. While the endangerment of the devil population precludes experimentation on large experimental groups, those examined in our study indicated that immunisation and immunotherapy with DFTD cells expressing surface MHC-I corresponded with effective anti-tumour responses. Tumour engraftment did not occur in one of the five immunised Tasmanian devils, and regression followed therapy of experimentally induced DFTD tumours in three Tasmanian devils. Regression correlated with immune cell infiltration and antibody responses against DFTD cells. These data support the concept that immunisation of devils with DFTD cancer cells can successfully induce humoral responses against DFTD and trigger immune-mediated regression of established tumours. Our findings support the feasibility of a protective DFTD vaccine and ultimately the preservation of the species.
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Neoplasias Faciales/inmunología , Inmunización/métodos , Inmunoterapia/métodos , Marsupiales/inmunología , Animales , Formación de Anticuerpos/inmunología , Neoplasias Faciales/terapia , Neoplasias Faciales/veterinaria , Femenino , Antígenos de Histocompatibilidad Clase I/inmunología , Inmunidad Humoral/inmunología , Masculino , Resultado del TratamientoRESUMEN
Pandoraea species are considered as emerging pathogens in people with cystic fibrosis (CF). The contribution of these organisms to disease progression in CF patients is not fully understood owing in large measure to the scant reports in clinical and research literature describing their colonization of CF patients and their associated virulence determinants. In an effort to increase awareness and evidence for Pandoraea spp. infection in people with CF, and to stimulate research aimed at unraveling the pathogenic properties of Pandoraea, we report a case of a 26-year-old Australian (Tasmanian) man with CF who was chronically infected with Pandoraea pnomenusa for at least one year prior to his death from respiratory failure. In addition, we describe for the first time evidence suggesting that this bacterium is a facultative anaerobe and report on the availability of a whole genome sequence for this organism. To the best of our knowledge, this report represents only the second clinical case study of P. pnomenusa infection in the world, and the first in an Australian CF patient.
RESUMEN
Neonates have a developing immune response, with a predisposition towards induction of tolerance. As the immune system develops, immunity rather than tolerance is induced, with this development of immunity occurring in response to external factors such as the environment. As ultraviolet radiation (UVR) suppresses immunity, it is likely that the effect of UVR on the neonatal immune system would be augmentation of the suppressive response. In support, childhood exposure to UVR has been linked with an increased incidence of melanoma; consistent with an increase in suppression. To address this, phenotypic and functional immune system studies were undertaken at 8 weeks after one single exposure of solar-simulated UVR to mice, when mice had reached adulthood. Subtle changes were observed in cell populations resident in the skin-draining lymph nodes (LNs) and there also appeared to be a subtle, but not statistically significant, increase in the production of interleukin-10 and interferon-γ. Importantly, these changes also corresponded with significant suppression of the contact hypersensitivity response in irradiated mice compared with their control counterparts. This suppression was apparent when antigen sensitisation occurred during the neonatal or adult period, and thus did not appear to be analogous to UVR-induced suppression in adults. Although the percentage of T regulatory cells was increased in the skin-draining LNs, they were induced in a different manner to those induced following adult UVR exposure, with no increase in function on a per-cell basis. It therefore appears that one single neonatal exposure to UVR alters development of the immune system, leading to long-term implications for induction of immunity.
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Sistema Inmunológico/efectos de la radiación , Tolerancia Inmunológica/efectos de la radiación , Ganglios Linfáticos/efectos de la radiación , Piel/inmunología , Piel/efectos de la radiación , Linfocitos T Reguladores/efectos de la radiación , Rayos Ultravioleta/efectos adversos , Animales , Animales Recién Nacidos/inmunología , Proliferación Celular/efectos de la radiación , Células Cultivadas , Dermatitis por Contacto/inmunología , Femenino , Hipersensibilidad , Interferón gamma/biosíntesis , Interleucina-10/biosíntesis , Ganglios Linfáticos/citología , Activación de Linfocitos/efectos de la radiación , Masculino , Ratones , Ratones Endogámicos BALB C , Oxazolona/inmunologíaRESUMEN
The neonatal immune environment and the events that occur during this time have profound effects for the adult period. While protective immune responses can develop, the neonatal immune system, particularly the skin immune system (SIS), tends to promote tolerance. With this information we undertook a number of studies to identify unique aspects of skin during the neonatal period. Proteomics revealed proteins uniquely expressed in neonatal, but not adult, skin (e.g. Stefin A, peroxiredoxins) and these may have implications in the development of SIS. Vitamin D was found to have a modulating role on SIS and this was apparent from the early neonatal period. Exposure of the neonatal skin to UV radiation altered the microenvironment resulting in the generation of regulatory T cells, which persisted in adult life. As the development of UV radiation-induced melanoma can occur following a single high dose (equivalent to burning in adults) to transgenic mice (hepatocyte growth factor/scatter factor or TPras) during the neonatal period, the early modulating events which lead to suppression may be relevant for the development of UV radiation-induced human melanoma. Any attempt to produce effective melanoma immunotherapy has to accommodate and overcome these barriers. Margaret Kripke's pioneering work on UV-induced immunosuppression still remains central to the understanding of the development of melanoma and how it frequently escapes the immune system.
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Sistema Inmunológico/inmunología , Sistema Inmunológico/efectos de la radiación , Melanoma/inmunología , Neoplasias Cutáneas/inmunología , Rayos Ultravioleta , Animales , Animales Recién Nacidos , Antígenos/inmunología , Humanos , Recién Nacido , Melanoma/patología , Neoplasias Cutáneas/patologíaRESUMEN
The Skin Immune System (SIS) is a relatively new concept central to the issue of cutaneous tumour surveillance. The Langerhans cell (LC) is a key component of SIS. Skin cancer causing agents such as ultraviolet B (UV-B) irradiation and chemical carcinogens like dimethylbenz(a)anthracene (DMBA) alter LC function, resulting in immunosuppression and the promotional phase of tumour development. Once tumours, such as melanoma, are established they may show evidence of tumour regression due to immune reaction but frequently escape immune attack and metastasise. This article explores our knowledge of LC and SIS in these responses. For tumour immunosurveillance to be an effective reality at the clinical level, experiments are required to provide a more precise base for immunotherapy.