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1.
J Cell Biochem ; 125(6): e30570, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38616697

RESUMEN

Runt-related transcription factor 1 (RUNX1) plays an important role in normal haematopoietic cell development and function, and its function is frequently disrupted in leukaemia. RUNX1 is widely recognised as a sequence-specific DNA binding factor that recognises the motif 5'-TG(T/C)GGT-3' in promoter and enhancer regions of its target genes. Moreover, RUNX1 fusion proteins, such as RUNX1-ETO formed by the t(8;21) translocation, retain the ability to recognise and bind to this sequence to elicit atypical gene regulatory effects on bona fide RUNX1 targets. However, our analysis of publicly available RUNX1 chromatin immunoprecipitation sequencing (ChIP-Seq) data has provided evidence challenging this dogma, revealing that this motif-specific model of RUNX1 recruitment and function is incomplete. Our analyses revealed that the majority of RUNX1 genomic localisation occurs outside of promoters, that 20% of RUNX1 binding sites lack consensus RUNX motifs, and that binding in the absence of a cognate binding site is more common in promoter regions compared to distal sites. Reporter assays demonstrate that RUNX1 can drive promoter activity in the absence of a recognised DNA binding motif, in contrast to RUNX1-ETO. RUNX1-ETO supresses activity when it is recruited to promoters containing a sequence specific motif, while interestingly, it binds but does not repress promoters devoid of a RUNX1 recognition site. These data suggest that RUNX1 regulation of target genes occurs through multiple mechanisms depending on genomic location, the type of regulatory element and mode of recruitment.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal , Regiones Promotoras Genéticas , Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Humanos , Sitios de Unión , Motivos de Nucleótidos , Unión Proteica , ADN/metabolismo , ADN/genética
2.
Br J Cancer ; 130(3): 347-357, 2024 02.
Artículo en Inglés | MEDLINE | ID: mdl-37945750

RESUMEN

Prostate cancer is one of the most commonly diagnosed cancers in men and unfortunately, disease will progress in up to a third of patients despite primary treatment. Currently, there is a significant lack of prognostic tests that accurately predict disease course; however, the acquisition of somatic chromosomal variation in the form of DNA copy number variants may help understand disease progression. Notably, studies have found that a higher burden of somatic copy number alterations (SCNA) correlates with more aggressive disease, recurrence after surgery and metastasis. Here we will review the literature surrounding SCNA formation, including the roles of key tumour suppressors and oncogenes (PTEN, BRCA2, NKX3.1, ERG and AR), and their potential to inform diagnostic and prognostic clinical testing to improve predictive value. Ultimately, SCNAs, or inherited germline alterations that predispose to SCNAs, could have significant clinical utility in diagnostic and prognostic tests, in addition to guiding therapeutic selection.


Asunto(s)
Variaciones en el Número de Copia de ADN , Neoplasias de la Próstata , Masculino , Humanos , Neoplasias de la Próstata/patología , Oncogenes , Pronóstico , Progresión de la Enfermedad
3.
Environ Res ; 243: 117808, 2024 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-38043901

RESUMEN

Pollen allergies pose a considerable global public health concern. Allergy risk can vary significantly within plant families, yet some key pollen allergens can only be identified to family level by current optical methods. Pollen information with greater taxonomic resolution is therefore required to best support allergy prevention and self-management. We used environmental DNA (eDNA) metabarcoding to deepen taxonomic insights into the seasonal composition of airborne pollen in cool temperate Australia, a region with high rates of allergic respiratory disease. In Hobart, Tasmania, we collected routine weekly air samples from December 2018 until October 2020 and sequenced the internal transcribed spacer 2 (ITS2) and chloroplastic tRNA-Leucine tRNA-Phenylalanine intergenic spacer (trnL-trnF) regions in order to address the following questions: a) What is the genus-level diversity of known and potential aeroallergens in Hobart, in particular, in the families Poaceae, Cupressaceae and Myrtaceae? b) How do the atmospheric concentrations of these taxa change over time, and c) Does trnL-trnF enhance resolution of biodiversity when used in addition to ITS2? Our results suggest that individuals in the region are exposed to temperate grasses including Poa and Bromus in the peak grass pollen season, however low levels of exposure to the subtropical grass Cynodon may occur in autumn and winter. Within Cupressaceae, both metabarcodes showed that exposure is predominantly to pollen from the introduced genera Cupressus and Juniperus. Only ITS2 detected the native genus, Callitris. Both metabarcodes detected Eucalyptus as the major Myrtaceae genus, with trnL-trnF exhibiting primer bias for this family. These findings help refine our understanding of allergy triggers in Tasmania and highlight the utility of multiple metabarcodes in aerobiome studies.


Asunto(s)
Polen , Rinitis Alérgica Estacional , Humanos , Estaciones del Año , Alérgenos/análisis , Poaceae , Australia , ARN de Transferencia
4.
Am J Respir Crit Care Med ; 207(9): 1194-1202, 2023 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-36602845

RESUMEN

Rationale: Idiopathic pulmonary fibrosis (IPF) is a rare, irreversible, and progressive disease of the lungs. Common genetic variants, in addition to nongenetic factors, have been consistently associated with IPF. Rare variants identified by candidate gene, family-based, and exome studies have also been reported to associate with IPF. However, the extent to which rare variants, genome-wide, may contribute to the risk of IPF remains unknown. Objectives: We used whole-genome sequencing to investigate the role of rare variants, genome-wide, on IPF risk. Methods: As part of the Trans-Omics for Precision Medicine Program, we sequenced 2,180 cases of IPF. Association testing focused on the aggregated effect of rare variants (minor allele frequency ⩽0.01) within genes or regions. We also identified individual rare variants that are influential within genes and estimated the heritability of IPF on the basis of rare and common variants. Measurements and Main Results: Rare variants in both TERT and RTEL1 were significantly associated with IPF. A single rare variant in each of the TERT and RTEL1 genes was found to consistently influence the aggregated test statistics. There was no significant evidence of association with other previously reported rare variants. The SNP heritability of IPF was estimated to be 32% (SE = 3%). Conclusions: Rare variants within the TERT and RTEL1 genes and well-established common variants have the largest contribution to IPF risk overall. Efforts in risk profiling or the development of therapies for IPF that focus on TERT, RTEL1, common variants, and environmental risk factors are likely to have the largest impact on this complex disease.


Asunto(s)
Fibrosis Pulmonar Idiopática , Humanos , Fibrosis Pulmonar Idiopática/genética , Secuenciación Completa del Genoma , Exoma
5.
Genes Chromosomes Cancer ; 62(5): 247-255, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36520140

RESUMEN

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.


Asunto(s)
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/genética
6.
Genet Med ; 25(3): 100354, 2023 03.
Artículo en Inglés | MEDLINE | ID: mdl-36496180

RESUMEN

PURPOSE: Patients with an underlying telomere biology disorder (TBD) have variable clinical presentations, and they can be challenging to diagnose clinically. A genomic diagnosis for patients presenting with TBD is vital for optimal treatment. Unfortunately, many variants identified during diagnostic testing are variants of uncertain significance. This complicates management decisions, delays treatment, and risks nonuptake of potentially curative therapies. Improved application of functional genomic evidence may reduce variants of uncertain significance classifications. METHODS: We systematically searched the literature for published functional assays interrogating TBD gene variants. When possible, established likely benign/benign and likely pathogenic/pathogenic variants were used to estimate the assay sensitivity, specificity, positive predictive value, negative predictive value, and odds of pathogenicity. RESULTS: In total, 3131 articles were screened and 151 met inclusion criteria. Sufficient data to enable a PS3/BS3 recommendation were available for TERT variants only. We recommend that PS3 and BS3 can be applied at a moderate and supportive level, respectively. PS3/BS3 application was limited by a lack of assay standardization and limited inclusion of benign variants. CONCLUSION: Further assay standardization and assessment of benign variants are required for optimal use of the PS3/BS3 criterion for TBD gene variant classification.


Asunto(s)
Pruebas Genéticas , Variación Genética , Humanos , Variación Genética/genética , Genoma Humano , Genómica , Telómero/genética
7.
Prostate ; 82(5): 540-550, 2022 04.
Artículo en Inglés | MEDLINE | ID: mdl-34994974

RESUMEN

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.


Asunto(s)
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/genética
8.
Breast Cancer Res Treat ; 192(1): 89-100, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35098437

RESUMEN

PURPOSE: ITGA2 encodes the integrin, α2 which mediates metastatic progression, and is a predictor of poor prognosis and chemoresistance in breast cancer. Decreased ITGA2 promoter methylation is implicated as a driver of increased gene expression in aggressive prostate and pancreatic tumours, however the contribution of altered methylation to ITGA2 expression changes in breast tumours has not been examined. METHODS: ITGA2 gene methylation and gene expression was examined in publicly available breast cancer datasets, and ITGA2 promoter methylation was mapped by targeted bisulphite sequencing analysis in breast tumour cell lines. The expression of a putative regulatory long noncoding RNA (lncRNA) was examined by qPCR and its' functionality was investigated using gene knockdown (antisense oligonucleotides) and over expression in breast cancer cell lines. RESULTS: In breast tumours and breast cancer cell lines the ITGA2 promoter is largely unmethylated, with gene expression variable in tumour subtypes, irrespective of promoter methylation. A novel lncRNA (AC025180.1;ENSG00000249899), named herein I2ALR, was identified at the ITGA2 gene locus, and was variably expressed in breast tumours and breast cancer cell subtypes. I2LAR knockdown resulted in upregulation of ITGA2 gene expression, whilst over-expression of I2ALR resulted in downregulation of ITGA2 mRNA. Further, examination of two downstream targets of ITGA2 associated with breast tumor stemness and metastasis (CCND1 and ACLY), revealed concomitant gene expression changes in response to I2ALR modulation. CONCLUSION: I2ALR represents a novel regulatory molecule targeting ITGA2 expression in breast tumours; a finding of significant and topical interest to the development of therapeutics targeting this integrin.


Asunto(s)
Neoplasias de la Mama , ARN Largo no Codificante , Neoplasias de la Mama/genética , Línea Celular Tumoral , Metilación de ADN , Regulación Neoplásica de la Expresión Génica , Humanos , Integrina alfa2/genética , Integrina alfa2/metabolismo , Integrinas , Masculino , ARN Largo no Codificante/genética
9.
Int J Cancer ; 149(5): 1089-1099, 2021 09 01.
Artículo en Inglés | MEDLINE | ID: mdl-33821477

RESUMEN

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/epidemiología
10.
Int J Equity Health ; 20(1): 29, 2021 01 10.
Artículo en Inglés | MEDLINE | ID: mdl-33423682

RESUMEN

BACKGROUND: Despite high level of health care need amongst people experiencing homelessness, poor access is a major concern. This is sometimes due to organisational and bureaucratic barriers, but also because they often feel stigmatised and treated badly when they do seek health care. The COVID-19 pandemic and the required social distancing measures have caused unprecedented disruption and change for the organisation of primary care, particularly for people experiencing homelessness. Against this backdrop there are many questions to address regarding whether the recent changes required to deliver services to people experiencing homelessness in the context of COVID-19 will help to address or compound problems in accessing care and inequalities in health outcomes. METHODS: An action led and participatory research methodology will be employed to address the study objectives. Interviews with people experiencing homelessness were will be conducted by a researcher with lived experience of homelessness. Researchers with lived experience are able to engage with vulnerable communities in an empathetic, non-judgemental way as their shared experience promotes a sense of trust and integrity, which in turn encourages participation in research and may help people speak more openly about their experience. The experiences of health professionals and stakeholders delivering and facilitating care for people experiencing homelessness during the pandemic will also be explored. DISCUSSION: It is important to explore whether recent changes to the delivery of primary care in response to the COVID-19 pandemic compromise the safety of people experiencing homelessness and exacerbate health inequalities. This could have implications for how primary healthcare is delivered to those experiencing homelessness not only for the duration of the pandemic but in the future.


Asunto(s)
COVID-19 , Accesibilidad a los Servicios de Salud/organización & administración , Personas con Mala Vivienda/psicología , Atención Primaria de Salud/organización & administración , Disparidades en el Estado de Salud , Humanos , Seguridad del Paciente , Investigación Cualitativa , Calidad de la Atención de Salud , Consulta Remota/organización & administración , Proyectos de Investigación
11.
Exp Cell Res ; 392(2): 112055, 2020 07 15.
Artículo en Inglés | MEDLINE | ID: mdl-32376286

RESUMEN

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.


Asunto(s)
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 Cultivadas
12.
Aust N Z J Obstet Gynaecol ; 60(2): 231-237, 2020 04.
Artículo en Inglés | MEDLINE | ID: mdl-31603537

RESUMEN

BACKGROUND: Vulvar cancer is rare and, as a result, is understudied. Treatment is predominantly surgery, irrespective of the type of vulvar cancer, and is associated with physical, emotional and sexual complications. A cluster of human papillomavirus (HPV)-dependent vulvar cancer patients was identified in Arnhem Land Northern Territory (NT), Australia, in which young Indigenous women were diagnosed at 70 times the national incidence rate. AIMS: To assess whether women from the Arnhem Land cluster differ from women with vulvar squamous cell carcinoma (VSCC) and vulvar intraepithelial neoplasia (VIN) resident elsewhere in the NT in recurrence after treatment, disease progression and mortality. MATERIALS AND METHODS: A retrospective cohort study of NT-resident women diagnosed with VIN or invasive vulvar cancer (VSCC) between 1 January 1993 and 30 June 2015 was undertaken. Time to recurrence was assessed using cumulative incidence plots and Fine and Gray competing risk regression models. Mean cumulative count was used to estimate the burden of recurrent events. RESULTS: Indigenous women from Arnhem Land experienced more recurrences after treatment than non-Indigenous women, the cancers recurred faster, and Indigenous women have worse survival at five years. CONCLUSIONS: In characterising the epidemiological features of this cluster, we have identified a particularly aggressive form of vulvar cancer. This provides a unique opportunity for elucidating the aetiopathological pathways driving vulvar cancer development that may ultimately lead to preventive and therapeutic targets for this neglected malignancy. Further, these findings have important implications for clinical practice and HPV vaccination policy in the affected population.


Asunto(s)
Carcinoma in Situ/epidemiología , Carcinoma de Células Escamosas/epidemiología , Pueblos Indígenas/estadística & datos numéricos , Recurrencia Local de Neoplasia/epidemiología , Papillomaviridae/patogenicidad , Neoplasias de la Vulva/epidemiología , Adulto , Estudios de Cohortes , Progresión de la Enfermedad , Femenino , Humanos , Incidencia , Persona de Mediana Edad , Northern Territory/epidemiología , Infecciones por Papillomavirus/complicaciones , Estudios Retrospectivos , Adulto Joven
14.
J Cell Physiol ; 233(4): 3439-3453, 2018 04.
Artículo en Inglés | MEDLINE | ID: mdl-28926098

RESUMEN

Integrins are transmembrane adhesion receptors that play an important role in hematopoiesis by facilitating interactions between hematopoietic cells and extracellular matrix components of the bone marrow and hematopoietic tissues. These interactions are important in regulating the function, proliferation, and differentiation of hematopoietic cells, as well as their homing and mobilization in the bone marrow. Not surprisingly altered expression and function of integrins plays a key role in the development and progression of cancer including leukemias. However, the regulation of integrin gene expression is not well characterized and the mechanisms by which integrin genes are disrupted in cancer remain unclear. Here we demonstrate for the first time that a key regulator of hematopoiesis, RUNX1, binds to and regulates the promoters of both the ITGA6 and ITGB4 genes in myeloid cells. The ITGA6 and ITGB4 integrin genes form the α6ß4 integrin receptor. However, our data indicate that RUNX1 functions differently at these two promoters. RUNX1 regulates ITGA6 through a consensus RUNX1 binding motif in its promoter. In contrast, although the ITGB4 promoter is also activated by RUNX1, it does so in the absence of a recognized consensus RUNX1 binding motif. Furthermore, our data suggest that regulation of ITGB4 may involve interactions between the promoter and upstream regulatory elements.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Regulación del Desarrollo de la Expresión Génica/genética , Integrina alfa6/metabolismo , Integrina beta4/metabolismo , Células Mieloides/metabolismo , Diferenciación Celular/genética , Embrión de Mamíferos/metabolismo , Hematopoyesis/genética , Células Madre Hematopoyéticas/metabolismo , Humanos , Mutación/genética , Regiones Promotoras Genéticas/genética
15.
Mamm Genome ; 29(11-12): 817-830, 2018 12.
Artículo en Inglés | MEDLINE | ID: mdl-30206651

RESUMEN

A low level of inflammation is an integral part of the balance between the immune system and the microbiota in the high antigen environment of the gastrointestinal tract and maintains homeostasis. A failure of this balance can lead to chronic intestinal inflammation and increase the chances to develop colorectal cancer significantly. The underlying mechanisms that link inflammation and carcinogenesis are not clear but the molecular platforms of the inflammasomes have been implicated. Inflammasomes are molecule complexes that are assembled in response to microbial components or cellular danger signals and facilitate the production of bioactive pro-inflammatory cytokines. One inflammasome in particular, NLRP3, has been analysed extensively in its contribution to colitis and has been shown to be associated with the development of colitis-associated colorectal cancer. This review will summarise the role of NLRP3 in intestinal inflammation, discuss some of the triggers of inflammation in the gastrointestinal tract such as diet and introduce some opportunities to use this inflammasome as therapeutic target for the treatment of colitis and colitis-associated colorectal cancer.


Asunto(s)
Colitis/inmunología , Neoplasias Colorrectales/etiología , Sistema Inmunológico/inmunología , Inflamasomas/inmunología , Inflamación/inmunología , Proteína con Dominio Pirina 3 de la Familia NLR/inmunología , Animales , Colitis/complicaciones , Neoplasias Colorrectales/patología , Humanos
16.
J Cell Physiol ; 231(3): 688-97, 2016 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-26241708

RESUMEN

Fucoidan, a natural component of seaweeds, is reported to have immunomodulatory and anti-tumor effects. The mechanisms underpinning these activities remain poorly understood. In this study, the cytotoxicity and anti-tumor activities of fucoidan were investigated in acute myeloid leukemia (AML) cells. The human AML cell lines NB4, KG1a, HL60, and K562 were treated with fucoidan and cell cycle, cell proliferation, and expression of apoptotic pathways molecules were analyzed. Fucoidan suppressed the proliferation and induced apoptosis through the intrinsic and extrinsic pathways in the acute promyelocytic leukemia (APL) cell lines NB4 and HL60, but not in KG1a and K562 cells. In NB4 cells, apoptosis was caspase-dependent as it was significantly attenuated by pre-treatment with a pan-caspase inhibitor. P21/WAF1/CIP1 was significantly up-regulated leading to cell cycle arrest. Fucoidan decreased the activation of ERK1/2 and down-regulated the activation of AKT through hypo-phosphorylation of Thr(308) residue but not Ser(473). In vivo, a xenograft model using the NB4 cells was employed. Mice were fed with fucoidan and tumor growth was measured following inoculation with NB4 cells. Subsequently, splenic natural killer (NK) cell cytotoxic activity was also examined. Oral doses of fucoidan significantly delayed tumor growth in the xenograft model and increased cytolytic activity of NK cells. Taken together, these data suggest that the selective inhibitory effect of fucoidan on APL cells and its protective effect against APL development in mice warrant further investigation of fucoidan as a useful agent in treatment of certain types of leukemia.


Asunto(s)
Apoptosis/efectos de los fármacos , Ciclo Celular/efectos de los fármacos , Diferenciación Celular/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Leucemia Promielocítica Aguda/patología , Polisacáridos/farmacología , Animales , Línea Celular Tumoral , Humanos , Leucemia Promielocítica Aguda/tratamiento farmacológico , Leucemia Promielocítica Aguda/metabolismo , Ratones Endogámicos BALB C
17.
J Cell Biochem ; 117(1): 49-58, 2016 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-26060100

RESUMEN

Activation of cytokine signaling via the leukemia inhibitory factor receptor (LIFR) plays an integral role in hematopoiesis, osteogenesis, and placental development, along with mediating neurotrophic mechanisms. However, the regulatory control of the LIFR gene has remained largely unexplored. Here, we characterize the LIFR gene as a novel target of the RUNX1 transcription factor. The RUNX1 transcription factor is an essential regulator of hematopoiesis and is a frequent target of point mutations and chromosomal alterations in leukemia. RUNX1 regulates hematopoiesis through its control of genes important for hematopoietic cell growth, proliferation, and differentiation, including a number of cytokines and cytokine receptors. LIFR is regulated by two alternate promoters: a placental-specific and a ubiquitously active general promoter. We show that both of these promoters are regulated by RUNX1. However, in myeloid cells LIFR expression is driven solely by the general LIFR promoter with our data indicating that the placental promoter is epigenetically silenced in these cells. While RUNX1 activates the LIFR general promoter, the oncogenic RUNX1-ETO fusion protein generated by the t(8;21) translocation commonly associated with acute myeloid leukemia represses promoter activity. The data presented here establish LIFR as a transcriptional target of RUNX1 and suggest that disruption of RUNX1 activity in myeloid cells may result in altered LIFR signaling in these cells.


Asunto(s)
Subunidad alfa 2 del Factor de Unión al Sitio Principal/metabolismo , Receptores OSM-LIF/metabolismo , Western Blotting , Diferenciación Celular/genética , Diferenciación Celular/fisiología , Línea Celular Tumoral , Proliferación Celular/genética , Proliferación Celular/fisiología , Inmunoprecipitación de Cromatina , Aberraciones Cromosómicas , Subunidad alfa 2 del Factor de Unión al Sitio Principal/genética , Humanos , Células Mieloides/metabolismo , Mutación Puntual/genética , Regiones Promotoras Genéticas/genética , Unión Proteica/genética , Unión Proteica/fisiología , Receptores de Citocinas/genética , Receptores de Citocinas/metabolismo , Receptores OSM-LIF/genética
18.
Hum Mol Genet ; 22(2): 408-15, 2013 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-23065704

RESUMEN

Genome-wide association studies (GWAS) have identified multiple common genetic variants associated with an increased risk of prostate cancer (PrCa), but these explain less than one-third of the heritability. To identify further susceptibility alleles, we conducted a meta-analysis of four GWAS including 5953 cases of aggressive PrCa and 11 463 controls (men without PrCa). We computed association tests for approximately 2.6 million SNPs and followed up the most significant SNPs by genotyping 49 121 samples in 29 studies through the international PRACTICAL and BPC3 consortia. We not only confirmed the association of a PrCa susceptibility locus, rs11672691 on chromosome 19, but also showed an association with aggressive PrCa [odds ratio = 1.12 (95% confidence interval 1.03-1.21), P = 1.4 × 10(-8)]. This report describes a genetic variant which is associated with aggressive PrCa, which is a type of PrCa associated with a poorer prognosis.


Asunto(s)
Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Neoplasias de la Próstata/genética , Sitios de Carácter Cuantitativo , Estudios de Casos y Controles , Progresión de la Enfermedad , Humanos , Masculino , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Reproducibilidad de los Resultados
19.
Prostate ; 75(7): 723-34, 2015 May.
Artículo en Inglés | MEDLINE | ID: mdl-25662931

RESUMEN

BACKGROUND: Integrin alpha2 beta1 (α2 ß1 ) plays an integral role in tumour cell invasion, metastasis and angiogenesis, and altered expression of the receptor has been linked to tumour prognosis in several solid tumours. However, the relationship is complex, with both increased and decreased expression associated with different stages of tumour metastases in several tumour types. The ITGA2 gene, which codes for the α2 subunit, was examined to investigate whether a large CpG island associated with its promoter region is involved in the differential expression of ITGA2 observed in prostate cancer. METHODS: Bisulphite sequencing of the ITGA2 promoter was used to assess methylation in formalin-fixed paraffin-embedded (FFPE) prostate tumour specimens and prostate cancer cell lines, PC3, 22Rv1 and LNCaP. Changes in ITGA2 mRNA expression were measured using quantitative PCR. ITGA2 functionality was interrogated using cell migration scratch assays and siRNA knockdown experiments. RESULTS: Bisulphite sequencing revealed strikingly decreased methylation at key CpG sites within the promoter of tumour samples, when compared with normal prostate tissue. Altered methylation of this CpG island is also associated with differences in expression in the non-invasive LNCaP, and the highly metastatic PC3 and 22Rv1 prostate cancer cell lines. Further bisulphite sequencing confirmed that selected CpGs were highly methylated in LNCaP cells, whilst only low levels of methylation were observed in PC3 and 22Rv1 cells, correlating with ITGA2 transcript levels. Examination of the increased expression of ITGA2 was shown to influence migratory potential via scratch assay in PC3, 22Rv1 and LNCaP cells, and was confirmed by siRNA knockdown experiments. CONCLUSIONS: Taken together, our data supports the assertion that epigenetic modification of the ITGA2 promoter is a mechanism by which ITGA2 expression is regulated.


Asunto(s)
Integrina alfa5beta1/genética , Neoplasias de la Próstata/genética , Anciano , Anciano de 80 o más Años , Línea Celular Tumoral , Movimiento Celular/genética , Metilación de ADN , Epigénesis Genética , Regulación Neoplásica de la Expresión Génica , Humanos , Integrina alfa5beta1/biosíntesis , Masculino , Persona de Mediana Edad , Regiones Promotoras Genéticas , Neoplasias de la Próstata/metabolismo , ARN Mensajero/química , ARN Mensajero/genética , ARN Interferente Pequeño/administración & dosificación , ARN Interferente Pequeño/genética , Reacción en Cadena en Tiempo Real de la Polimerasa , Análisis de Secuencia de ADN
20.
Mol Med ; 21: 400-9, 2015 Mar 26.
Artículo en Inglés | MEDLINE | ID: mdl-25822796

RESUMEN

The field of epigenetics and our understanding of the mechanisms that regulate the establishment, maintenance and heritability of epigenetic patterns continue to grow at a remarkable rate. This information is providing increased understanding of the role of epigenetic changes in disease, insight into the underlying causes of these epigenetic changes and revealing new avenues for therapeutic intervention. Epigenetic modifiers are increasingly being pursued as therapeutic targets in a range of diseases, with a number of agents targeting epigenetic modifications already proving effective in diseases such as cancer. Although it is well established that DNA mutations and aberrant expression of epigenetic modifiers play a key role in disease, attention is now turning to the interplay between genetic and epigenetic factors in complex disease etiology. The role of genetic variability in determining epigenetic profiles, which can then be modified by environmental and stochastic factors, is becoming more apparent. Understanding the interplay between genetic and epigenetic factors is likely to aid in identifying individuals most likely to benefit from epigenetic therapies. This goal is coming closer to realization because of continual advances in laboratory and statistical tools enabling improvements in the integration of genomic, epigenomic and phenotypic data.


Asunto(s)
Metilación de ADN/genética , Epigénesis Genética , ARN no Traducido/genética , Eucromatina/genética , Terapia Genética , Genoma Humano , Heterocromatina/genética , Histonas/genética , Humanos , Mutación
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