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1.
Cancers (Basel) ; 16(11)2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38893272

RESUMO

Sortilin is an important regulator with potential tumour-suppressor function by limiting EGFR signalling. In this study, we undertook a comprehensive expression analysis of sortilin transcript variants and the DNA methylation status of their corresponding promoters in human non-small cell carcinomas (NSCLCs). RNA/DNA was extracted from 81 NSCLC samples and paired normal tissue. mRNA expression was measured by qPCR and DNA methylation determined by pyrosequencing. BigDye-terminator sequencing was used to confirm exon-8 alternative splicing. Results demonstrated that both SORT1A and SORT1B variants were downregulated in lung tumours. The SORT1A/SORT1B expression ratio was higher in tumours compared to normal tissue. SORT1B promoter hypermethylation was detected in lung tumours compared to normal lung (median difference 14%, Mann-Whitney test p = 10-6). Interestingly, SORT1B is hypermethylated in white blood cells, but a small and very consistent drop in methylation (6%, p = 10-15) was observed in the lung cancer cases compared to control subjects. We demonstrate that the SORT1B exon-8 splice variation, reported in sequence databases, is also a feature of SORT1A. The significantly altered quantitative and qualitative characteristics of sortilin mRNA in NSCLC indicate a significant involvement in tumour pathogenesis and may have significant impact for its utility as a predictive marker in lung cancer management.

2.
Oncol Lett ; 27(5): 197, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38516679

RESUMO

Oral squamous cell carcinoma (OSCC) is a frequent human malignancy that demonstrates a range of genetic and epigenetic alterations. Histone deacetylases (HDACs) are key epigenetic regulators of cell-cycle progression, differentiation and apoptosis and their dysregulation is implicated in cancer development. HDACs are promising targets for anticancer therapy through the utilisation of HDAC inhibitors (HDACis). OSCC cells have been shown to have low levels of histone acetylation, suggesting that HDACis may produce beneficial effects in patients with OSCC. Valproic acid (VPA) is a class I and IIa HDACi and, therefore, may be useful in anticancer therapy. VPA has been reported as a chemo-preventive epigenetic agent in individuals with high-risk oral dysplasia (OD) and thus associated with a reduced risk of HNSCC. It is hypothesised that HDAC inhibition by VPA triggers a change in the expression levels of different HDAC family gene-members. The present review summarises the current literature on HDAC expression changes in response to VPA in oral cancer patients and in vitro studies in an effort to better understand the potential epigenetic impact of VPA treatment. The present review outlined the need for exploring supportive evidence of the chemo-preventive role played by VPA-based epigenetic modification in treating oral pre-cancerous lesions and, thus, providing a novel tolerable chemotherapeutic strategy for patients with oral cancer.

3.
J Mol Biol ; 436(4): 168434, 2024 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-38182103

RESUMO

Certain members of the ADP-ribosyltransferase superfamily (ARTD or PARP enzymes) catalyse ADP-ribosylation in response to cellular stress, DNA damage and viral infection and are upregulated in various tumours. PARP9, its binding partner DTX3L and PARP14 protein levels are significantly correlated in head and neck squamous cell carcinoma (HNSCC) and other tumour types though a mechanism where PARP9/DTX3L regulates PARP14 post-transcriptionally. Depleting PARP9, DTX3L or PARP14 expression in HNSCC or HeLa cell lines decreases cell survival through a reduction of proliferation and an increase in apoptosis. A partial rescue of survival was achieved by expressing a PARP14 truncation containing a predicted eukaryotic type I KH domain. KH-like domains were also found in PARP9 and in DTX3L and contributed to protein-protein interactions between PARP9-DTX3L and PARP14-DTX3L. Homodimerization of DTX3L was also coordinated by a KH-like domain and was disrupted by site-specific mutation. Although, cell survival promoted by PARP14 did not require ADP-ribosyltransferase activity, interaction of DTX3L in vitro suppressed PARP14 auto-ADP-ribosylation and promoted trans-ADP-ribosylation of PARP9 and DTX3L. In summary, we characterised PARP9-DTX3L-PARP14 interactions important to pro-survival signalling in HNSCC cells, albeit in PARP14 catalytically independent fashion.


Assuntos
Neoplasias de Cabeça e Pescoço , Proteínas de Neoplasias , Poli(ADP-Ribose) Polimerases , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ubiquitina-Proteína Ligases , Humanos , Sobrevivência Celular , Neoplasias de Cabeça e Pescoço/enzimologia , Neoplasias de Cabeça e Pescoço/patologia , Células HeLa , Proteínas de Neoplasias/química , Poli(ADP-Ribose) Polimerases/química , Carcinoma de Células Escamosas de Cabeça e Pescoço/enzimologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia , Ubiquitina-Proteína Ligases/química , Domínios Proteicos
4.
Colloids Surf B Biointerfaces ; 229: 113466, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37515959

RESUMO

Lung cancer is one of the most aggressive and deadliest health threats. There has been an increasing interest in non-coding RNA (ncRNA) recently, especially in the areas of carcinogenesis and tumour progression. However, ncRNA-directed therapies are still encountering obstacles on their way to the clinic. In the present article, we provide an overview on the potential of targeting ncRNA in the treatment of lung cancer. Then, we discuss the delivery challenges and recent approaches enabling the delivery of ncRNA-directed therapies to the lung cancer cells, where we illuminate some advanced technologies including chemically-modified oligonucleotides, nuclear targeting, and three-dimensional in vitro models. Furthermore, advanced non-viral delivery systems recruiting nanoparticles, biomimetic delivery systems, and extracellular vesicles are also highlighted. Lastly, the challenges limiting the clinical trials on the therapeutic targeting of ncRNAs in lung cancer and future directions to tackle them are explored.


Assuntos
Neoplasias Pulmonares , RNA não Traduzido , Humanos , RNA não Traduzido/genética , RNA não Traduzido/uso terapêutico , Neoplasias Pulmonares/terapia , Neoplasias Pulmonares/tratamento farmacológico , Carcinogênese , Terapia de Alvo Molecular/métodos
5.
EBioMedicine ; 93: 104686, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37379654

RESUMO

BACKGROUND: Individual plasma proteins have been identified as minimally invasive biomarkers for lung cancer diagnosis with potential utility in early detection. Plasma proteomes provide insight into contributing biological factors; we investigated their potential for future lung cancer prediction. METHODS: The Olink® Explore-3072 platform quantitated 2941 proteins in 496 Liverpool Lung Project plasma samples, including 131 cases taken 1-10 years prior to diagnosis, 237 controls, and 90 subjects at multiple times. 1112 proteins significantly associated with haemolysis were excluded. Feature selection with bootstrapping identified differentially expressed proteins, subsequently modelled for lung cancer prediction and validated in UK Biobank data. FINDINGS: For samples 1-3 years pre-diagnosis, 240 proteins were significantly different in cases; for 1-5 year samples, 117 of these and 150 further proteins were identified, mapping to significantly different pathways. Four machine learning algorithms gave median AUCs of 0.76-0.90 and 0.73-0.83 for the 1-3 year and 1-5 year proteins respectively. External validation gave AUCs of 0.75 (1-3 year) and 0.69 (1-5 year), with AUC 0.7 up to 12 years prior to diagnosis. The models were independent of age, smoking duration, cancer histology and the presence of COPD. INTERPRETATION: The plasma proteome provides biomarkers which may be used to identify those at greatest risk of lung cancer. The proteins and the pathways are different when lung cancer is more imminent, indicating that both biomarkers of inherent risk and biomarkers associated with presence of early lung cancer may be identified. FUNDING: Janssen Pharmaceuticals Research Collaboration Award; Roy Castle Lung Cancer Foundation.


Assuntos
Biomarcadores Tumorais , Neoplasias Pulmonares , Humanos , Biomarcadores Tumorais/metabolismo , Detecção Precoce de Câncer , Neoplasias Pulmonares/diagnóstico , Biomarcadores , Proteínas Sanguíneas , Fumar , Proteoma
6.
Front Cell Dev Biol ; 10: 1022422, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36313557

RESUMO

Genomic imprinting is an epigenetic process through which genes are expressed in a parent-of-origin specific manner resulting in mono-allelic or strongly biased expression of one allele. For some genes, imprinted expression may be tissue-specific and reliant on CTCF-influenced enhancer-promoter interactions. The Peg13 imprinting cluster is associated with neurodevelopmental disorders and comprises canonical imprinted genes, which are conserved between mouse and human, as well as brain-specific imprinted genes in mouse. The latter consist of Trappc9, Chrac1 and Ago2, which have a maternal allelic expression bias of ∼75% in brain. Findings of such allelic expression biases on the tissue level raise the question of how they are reflected in individual cells and whether there is variability and mosaicism in allelic expression between individual cells of the tissue. Here we show that Trappc9 and Ago2 are not imprinted in hippocampus-derived neural stem cells (neurospheres), while Peg13 retains its strong bias of paternal allele expression. Upon analysis of single neural stem cells and in vitro differentiated neurons, we find not uniform, but variable states of allelic expression, especially for Trappc9 and Ago2. These ranged from mono-allelic paternal to equal bi-allelic to mono-allelic maternal, including biased bi-allelic transcriptional states. Even Peg13 expression deviated from its expected paternal allele bias in a small number of cells. Although the cell populations consisted of a mosaic of cells with different allelic expression states, as a whole they reflected bulk tissue data. Furthermore, in an attempt to identify potential brain-specific regulatory elements across the Trappc9 locus, we demonstrate tissue-specific and general silencer activities, which might contribute to the regulation of its imprinted expression bias.

7.
Eur J Med Res ; 27(1): 14, 2022 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-35101137

RESUMO

BACKGROUND: Aberrant Wnt signalling, regulating cell development and stemness, influences the development of many cancer types. The Aryl hydrocarbon receptor (AhR) mediates tumorigenesis of environmental pollutants. Complex interaction patterns of genes assigned to AhR/Wnt-signalling were recently associated with lung cancer susceptibility. AIM: To assess the association and predictive ability of AhR/Wnt-genes with lung cancer in cases and controls of European descent. METHODS: Odds ratios (OR) were estimated for genomic variants assigned to the Wnt agonist and the antagonistic genes DKK2, DKK3, DKK4, FRZB, SFRP4 and Axin2. Logistic regression models with variable selection were trained, validated and tested to predict lung cancer, at which other previously identified SNPs that have been robustly associated with lung cancer risk could also enter the model. Furthermore, decision trees were created to investigate variant × variant interaction. All analyses were performed for overall lung cancer and for subgroups. RESULTS: No genome-wide significant association of AhR/Wnt-genes with overall lung cancer was observed, but within the subgroups of ever smokers (e.g., maker rs2722278 SFRP4; OR = 1.20; 95% CI 1.13-1.27; p = 5.6 × 10-10) and never smokers (e.g., maker rs1133683 Axin2; OR = 1.27; 95% CI 1.19-1.35; p = 1.0 × 10-12). Although predictability is poor, AhR/Wnt-variants are unexpectedly overrepresented in optimized prediction scores for overall lung cancer and for small cell lung cancer. Remarkably, the score for never-smokers contained solely two AhR/Wnt-variants. The optimal decision tree for never smokers consists of 7 AhR/Wnt-variants and only two lung cancer variants. CONCLUSIONS: The role of variants belonging to Wnt/AhR-pathways in lung cancer susceptibility may be underrated in main-effects association analysis. Complex interaction patterns in individuals of European descent have moderate predictive capacity for lung cancer or subgroups thereof, especially in never smokers.


Assuntos
Fatores de Transcrição Hélice-Alça-Hélice Básicos/genética , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla/métodos , Neoplasias Pulmonares/genética , RNA Neoplásico/genética , Receptores de Hidrocarboneto Arílico/genética , Fatores de Transcrição Hélice-Alça-Hélice Básicos/metabolismo , Feminino , Genótipo , Humanos , Neoplasias Pulmonares/metabolismo , Masculino , Pessoa de Meia-Idade , Receptores de Hidrocarboneto Arílico/metabolismo , Via de Sinalização Wnt
8.
Radiother Oncol ; 165: 87-93, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34757119

RESUMO

BACKGROUND/AIM: Utilising radiotherapy in the management of head and neck cancer (HNC) often results in long term toxicities. Mandibular osteoradionecrosis (ORN) represents a late toxicity associated with significant morbidity. We aim to identify a panel of common genetic variants which can predict ORN to aid development of personalised radiotherapy protocols. METHOD: Single nucleotide polymorphism (SNP) arrays were applied to DNA samples from patients who had prior HNC radiotherapy and minimum two years follow-up. A case cohort of mandibular ORN was compared to a control group of participants recruited to CRUK HOPON clinical trial. Relevant clinical parameters influencing ORN risk (e.g. smoking/alcohol) were collected. Significant associations from array data were internally validated using polymerase chain reaction (PCR) and pyrosequencing. RESULTS: Following inclusion of 141 patients in the analysis (52 cases, 89 controls), a model predictive for ORN was developed; after controlling for alcohol consumption, smoking, and age, 4053 SNPs were identified as significant. This was reduced to a representative model of 18 SNPs achieving 92% accuracy. Following internal technical validation, a six SNP model (rs34798038, rs6011731, rs2348569, rs530752, rs7477958, rs1415848) was retained within multivariate regression analysis (ROC AUC 0.859). Of these, four SNPs (rs34798038 (A/G) (p 0.006), rs6011731 (C/T) (p 0.018), rs530752 (A/G) (p 0.046) and rs2348569 (G/G) (p 0.005)) were significantly associated with the absence of ORN. CONCLUSION: This is the first genome wide association study in HNC using ORN as the endpoint and offers new insight into ORN pathogenesis. Subject to validation, these variants may guide patient selection for personalised radiotherapy strategies.


Assuntos
Neoplasias de Cabeça e Pescoço , Osteorradionecrose , Estudos de Coortes , Estudo de Associação Genômica Ampla , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/radioterapia , Humanos , Mandíbula , Osteorradionecrose/genética , Estudos Retrospectivos
9.
Trials ; 22(1): 428, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34225765

RESUMO

BACKGROUND: Sodium valproate (VPA) has been associated with a reduced risk of head and neck cancer development. The potential protective mechanism of action is believed to be via inhibition of histone deacetylase and subsequent epigenetic reprogramming. SAVER is a phase IIb open-label, randomised control trial of VPA as a chemopreventive agent in patients with high-risk oral epithelial dysplasia (OED). The aim of the trial is to gather preliminary evidence of the clinical and biological effects of VPA upon OED and assess the feasibility and acceptability of such a trial, with a view to inform a future definitive phase III study. METHODS: One hundred and ten patients with high-risk OED will be recruited from up to 10 secondary care sites in the UK and randomised into either VPA or observation only for 4 months. Women of childbearing potential will be excluded due to the teratogenic properties of VPA. Tissue and blood samples will be collected prior to randomisation and on the last day of the intervention/observation-only period (end of 4 months). Clinical measurement and additional safety bloods will be taken at multiple time points during the trial. The primary outcome will be a composite, surrogate endpoint of change in lesion size, change in grade of dysplasia and change in LOH profile at 8 key microsatellite regions. Feasibility outcomes will include recruitment targets, compliance with the study protocol and adverse effects. A qualitative sub-study will explore patient experience and perception of the trial. DISCUSSION: The current management options for patients with high-risk OED are limited and mostly include surgical resection and clinical surveillance. However, there remains little evidence whether surgery can effectively lead to a notable reduction in the risk of oral cancer development. Similarly, surveillance is associated with concerns regarding delayed diagnosis of OED progressing to malignancy. The SAVER trial provides an opportunity to investigate the effects of a repurposed, inexpensive and well-tolerated medication as a potential chemopreventive strategy for patients with high-risk OED. The clinical and biological findings of SAVER will inform the appropriateness, design and feasibility of a definitive phase III trial. TRIAL REGISTRATION: The trial is registered with the European Clinical Trials Database ( Eudra-CT 2018-000197-30 ). ( http://www.isrctn.com/ISRCTN12448611 ). The trial was prospectively registered on 24/04/2018.


Assuntos
COVID-19 , Ácido Valproico , Ensaios Clínicos Fase II como Assunto , Epigênese Genética , Feminino , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , SARS-CoV-2 , Resultado do Tratamento , Ácido Valproico/efeitos adversos
10.
J Immunol ; 207(1): 55-64, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-34135066

RESUMO

Effector CD4+ T lymphocytes contribute to inflammation and tissue damage in psoriasis, but the underlying molecular mechanisms remain poorly understood. The transcription factor CREMα controls effector T cell function in people with systemic autoimmune diseases. The inhibitory surface coreceptor PD-1 plays a key role in the control of effector T cell function and its therapeutic inhibition in patients with cancer can cause psoriasis. In this study, we show that CD4+ T cells from patients with psoriasis and psoriatic arthritis exhibit increased production of IL-17 but decreased expression of IL-2 and PD-1. In genetically modified mice and Jurkat T cells CREMα expression was linked to low PD-1 levels. We demonstrate that CREMα is recruited to the proximal promoter of PDCD1 in which it trans-represses gene expression and corecruits DNMT3a-mediating DNA methylation. As keratinocytes limit inflammation by PD-1 ligand expression and, in this study, reported reduced expression of PD-1 on CD4+ T cells is linked to low IL-2 and high IL-17A production, our studies reveal a molecular pathway in T cells from people with psoriasis that can deserve clinical exploitation.


Assuntos
Artrite Psoriásica/imunologia , Linfócitos T CD4-Positivos/imunologia , Modulador de Elemento de Resposta do AMP Cíclico/imunologia , Receptor de Morte Celular Programada 1/imunologia , Animais , Humanos , Camundongos , Camundongos Endogâmicos C57BL
11.
iScience ; 24(4): 102273, 2021 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-33851096

RESUMO

DNA methyl transferase-1 or DNMT1 maintains DNA methylation in the genome and is important for regulating gene expression in cells. Aberrant changes in DNMT1 activity and DNA methylation are commonly observed in cancers and many other diseases. Recently, a number of long intergenic non-protein-coding RNAs or lincRNAs have been shown to play a role in regulating DNMT1 activity. CCDC26 is a nuclear lincRNA that is frequently mutated in cancers and is a hotbed for disease-associated single nucleotide changes. However, the functional mechanism of CCDC26 is not understood. Here, we show that this lincRNA is concentrated on the nuclear periphery. Strikingly, in the absence of CCDC26 lincRNA, DNMT1 is mis-located in the cytoplasm, and the genomic DNA is significantly hypomethylated. This is accompanied by double-stranded DNA breaks and increased cell death. These results point to a previously unrecognized mechanism of lincRNA-mediated subcellular localization of DNMT1 and regulation of DNA methylation.

12.
NPJ Precis Oncol ; 5(1): 12, 2021 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-33594163

RESUMO

Recent studies suggest that rare variants exhibit stronger effect sizes and might play a crucial role in the etiology of lung cancers (LC). Whole exome plus targeted sequencing of germline DNA was performed on 1045 LC cases and 885 controls in the discovery set. To unveil the inherited causal variants, we focused on rare and predicted deleterious variants and small indels enriched in cases or controls. Promising candidates were further validated in a series of 26,803 LCs and 555,107 controls. During discovery, we identified 25 rare deleterious variants associated with LC susceptibility, including 13 reported in ClinVar. Of the five validated candidates, we discovered two pathogenic variants in known LC susceptibility loci, ATM p.V2716A (Odds Ratio [OR] 19.55, 95%CI 5.04-75.6) and MPZL2 p.I24M frameshift deletion (OR 3.88, 95%CI 1.71-8.8); and three in novel LC susceptibility genes, POMC c.*28delT at 3' UTR (OR 4.33, 95%CI 2.03-9.24), STAU2 p.N364M frameshift deletion (OR 4.48, 95%CI 1.73-11.55), and MLNR p.Q334V frameshift deletion (OR 2.69, 95%CI 1.33-5.43). The potential cancer-promoting role of selected candidate genes and variants was further supported by endogenous DNA damage assays. Our analyses led to the identification of new rare deleterious variants with LC susceptibility. However, in-depth mechanistic studies are still needed to evaluate the pathogenic effects of these specific alleles.

13.
Blood ; 137(22): 3064-3078, 2021 06 03.
Artigo em Inglês | MEDLINE | ID: mdl-33512408

RESUMO

Chronic lymphocytic leukemia (CLL) remains incurable despite B-cell receptor-targeted inhibitors revolutionizing treatment. This suggests that other signaling molecules are involved in disease escape mechanisms and resistance. Toll-like receptor 9 (TLR9) is a promising candidate that is activated by unmethylated cytosine guanine dinucleotide-DNA. Here, we show that plasma from patients with CLL contains significantly more unmethylated DNA than plasma from healthy control subjects (P < .0001) and that cell-free DNA levels correlate with the prognostic markers CD38, ß2-microglobulin, and lymphocyte doubling time. Furthermore, elevated cell-free DNA was associated with shorter time to first treatment (hazard ratio, 4.0; P = .003). We also show that TLR9 expression was associated with in vitro CLL cell migration (P < .001), and intracellular endosomal TLR9 strongly correlated with aberrant surface expression (sTLR9; r = 0.9). In addition, lymph node-derived CLL cells exhibited increased sTLR9 (P = .016), and RNA-sequencing of paired sTLR9hi and sTLR9lo CLL cells revealed differential transcription of genes involved in TLR signaling, adhesion, motility, and inflammation in sTLR9hi cells. Mechanistically, a TLR9 agonist, ODN2006, promoted CLL cell migration (P < .001) that was mediated by p65 NF-κB and STAT3 transcription factor activation. Importantly, autologous plasma induced the same effects, which were reversed by a TLR9 antagonist. Furthermore, high TLR9 expression promoted engraftment and rapid disease progression in a NOD/Shi-scid/IL-2Rγnull mouse xenograft model. Finally, we showed that dual targeting of TLR9 and Bruton's tyrosine kinase (BTK) was strongly synergistic (median combination index, 0.2 at half maximal effective dose), which highlights the distinct role for TLR9 signaling in CLL and the potential for combined targeting of TLR9 and BTK as a more effective treatment strategy in this incurable disease.


Assuntos
Movimento Celular/efeitos dos fármacos , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Leucemia Linfocítica Crônica de Células B , Proteínas de Neoplasias , Oligodesoxirribonucleotídeos/farmacologia , Receptor Toll-Like 9 , Animais , Feminino , Humanos , Leucemia Linfocítica Crônica de Células B/tratamento farmacológico , Leucemia Linfocítica Crônica de Células B/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos NOD , Camundongos SCID , Proteínas de Neoplasias/agonistas , Proteínas de Neoplasias/metabolismo , Transdução de Sinais/efeitos dos fármacos , Receptor Toll-Like 9/agonistas , Receptor Toll-Like 9/metabolismo , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Breast Cancer Res ; 22(1): 126, 2020 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-33198803

RESUMO

BACKGROUND: Activating transcription factor-2 (ATF2), a member of the leucine zipper family of DNA binding proteins, has been implicated as a tumour suppressor in breast cancer. However, its exact role in breast cancer endocrine resistance is still unclear. We have previously shown that silencing of ATF2 leads to a loss in the growth-inhibitory effects of tamoxifen in the oestrogen receptor (ER)-positive, tamoxifen-sensitive MCF7 cell line and highlighted that this multi-faceted transcription factor is key to the effects of tamoxifen in an endocrine sensitive model. In this work, we explored further the in vitro role of ATF2 in defining the resistance to endocrine treatment. MATERIALS AND METHODS: We knocked down ATF2 in TAMR, LCC2 and LCC9 tamoxifen-resistant breast cancer cell lines as well as the parental tamoxifen sensitive MCF7 cell line and investigated the effects on growth, colony formation and cell migration. We also performed a microarray gene expression profiling (Illumina Human HT12_v4) to explore alterations in gene expression between MCF7 and TAMRs after ATF2 silencing and confirmed gene expression changes by quantitative RT-PCR. RESULTS: By silencing ATF2, we observed a significant growth reduction of TAMR, LCC2 and LCC9 with no such effect observed with the parental MCF7 cells. ATF2 silencing was also associated with a significant inhibition of TAMR, LCC2 and LCC9 cell migration and colony formation. Interestingly, knockdown of ATF2 enhanced the levels of ER and ER-regulated genes, TFF1, GREB1, NCOA3 and PGR, in TAMR cells both at RNA and protein levels. Microarray gene expression identified a number of genes known to mediate tamoxifen resistance, to be differentially regulated by ATF2 in TAMR in relation to the parental MCF7 cells. Moreover, differential pathway analysis confirmed enhanced ER activity after ATF2 knockdown in TAMR cells. CONCLUSION: These data demonstrate that ATF2 silencing may overcome endocrine resistance and highlights further the dual role of this transcription factor that can mediate endocrine sensitivity and resistance by modulating ER expression and activity.


Assuntos
Fator 2 Ativador da Transcrição/metabolismo , Antineoplásicos Hormonais/farmacologia , Neoplasias da Mama/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos/genética , Regulação Neoplásica da Expressão Gênica/genética , Fator 2 Ativador da Transcrição/genética , Antineoplásicos Hormonais/uso terapêutico , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Movimento Celular/genética , Feminino , Perfilação da Expressão Gênica , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Células MCF-7 , Análise de Sequência com Séries de Oligonucleotídeos , Receptores de Estrogênio/análise , Receptores de Estrogênio/antagonistas & inibidores , Receptores de Estrogênio/genética , Receptores de Estrogênio/metabolismo , Tamoxifeno/farmacologia , Tamoxifeno/uso terapêutico
15.
Biochim Biophys Acta Rev Cancer ; 1874(2): 188429, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32956766

RESUMO

Neurotensin receptor-3 or sortilin is a vacuolar protein sorting 10 protein domain (Vps10p) has been firstly discovered in the human brain, it acts as receptor or co-receptor of the cell and traffics different proteins within the cell. Sortilin deregulation contributes to the development of several diseases, including neurological diseases and cancer. On the other hand, neurotrophins which are a family of proteins essential for the nervous system development, function and plasticity. The first discovered member is the nerve growth factor; other members are brain-derived growth factor, neurotrophin-3 and neurotrophin-4. Nerve growth factor and brain-derived growth factor are the common neurotrophins that have a role in cancer. Neurotrophins initiate their signals through interaction with tyrosine receptor kinases TrkA, TrkB, and TrkC; each member has an affinity for a specific receptor to stimulate cell survival, while the interaction with p75NTR initiates cell apoptosis pathway by forming a complex with sortilin and neurotrophin precursors. A number of therapeutic approaches are emerging to target the neurotrophins pathway as well as sortilin.


Assuntos
Proteínas Adaptadoras de Transporte Vesicular/metabolismo , Neoplasias/metabolismo , Fatores de Crescimento Neural/metabolismo , Doenças do Sistema Nervoso/metabolismo , Regulação da Expressão Gênica , Humanos , Transporte Proteico , Receptores Proteína Tirosina Quinases/metabolismo , Transdução de Sinais
16.
FASEB J ; 34(9): 11844-11859, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32652768

RESUMO

Lactation-induced bone loss occurs due to high calcium requirements for fetal growth but skeletal recovery is normally achieved promptly postweaning. Dietary protein is vital for fetus and mother but the effects of protein undernutrition on the maternal skeleton and skeletal muscles are largely unknown. We used mouse dams fed with normal (N, 20%) or low (L, 8%) protein diet during gestation and lactation and maintained on the same diets (NN, LL) or switched from low to normal (LN) during a 28 d skeletal restoration period post lactation. Skeletal muscle morphology and neuromuscular junction integrity was not different between any of the groups. However, dams fed the low protein diet showed extensive bone loss by the end of lactation, followed by full skeletal recovery in NN dams, partial recovery in LN and poor bone recovery in LL dams. Primary osteoblasts from low protein diet fed mice showed decreased in vitro bone formation and decreased osteogenic marker gene expression; promoter methylation analysis by pyrosequencing showed no differences in Bmpr1a, Ptch1, Sirt1, Osx, and Igf1r osteoregulators, while miR-26a, -34a, and -125b expression was found altered in low protein fed mice. Therefore, normal protein diet is indispensable for maternal musculoskeletal health during the reproductive period.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal/fisiologia , Doenças Ósseas Metabólicas/fisiopatologia , Dieta com Restrição de Proteínas , Lactação/fisiologia , Músculo Esquelético/fisiologia , Reprodução/fisiologia , Animais , Animais Recém-Nascidos , Peso Corporal , Doenças Ósseas Metabólicas/genética , Doenças Ósseas Metabólicas/metabolismo , Feminino , Perfilação da Expressão Gênica , Humanos , Camundongos Transgênicos , MicroRNAs/genética , Músculo Esquelético/metabolismo , Osteoblastos/metabolismo , Osteogênese/genética , Desmame
17.
Cancer Res ; 80(13): 2861-2873, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32393661

RESUMO

Although fibrotic stroma forms an integral component of pancreatic diseases, whether fibroblasts programmed by different types of pancreatic diseases are phenotypically distinct remains unknown. Here, we show that fibroblasts isolated from patients with pancreatic ductal adenocarcinoma (PDAC), chronic pancreatitis (CP), periampullary tumors, and adjacent normal (NA) tissue (N = 34) have distinct mRNA and miRNA profiles. Compared with NA fibroblasts, PDAC-associated fibroblasts were generally less sensitive to an antifibrotic stimulus (NPPB) and more responsive to positive regulators of activation such as TGFß1 and WNT. Of the disease-associated fibroblasts examined, PDAC- and CP-derived fibroblasts shared greatest similarity, yet PDAC-associated fibroblasts expressed higher levels of tenascin C (TNC), a finding attributable to miR-137, a novel regulator of TNC. TNC protein and transcript levels were higher in PDAC tissue versus CP tissue and were associated with greater levels of stromal activation, and conditioned media from TNC-depleted PDAC-associated fibroblasts modestly increased both PDAC cell proliferation and PDAC cell migration, indicating that stromal TNC may have inhibitory effects on PDAC cells. Finally, circulating TNC levels were higher in patients with PDAC compared with CP. Our characterization of pancreatic fibroblast programming as disease-specific has consequences for therapeutic targeting and for the manner in which fibroblasts are used in research. SIGNIFICANCE: Primary fibroblasts derived from various types of pancreatic diseases possess and retain distinct molecular and functional characteristics in culture, providing a series of cellular models for treatment development and disease-specific research.


Assuntos
Adenocarcinoma/patologia , Carcinoma Ductal Pancreático/patologia , Fibroblastos/patologia , Regulação Neoplásica da Expressão Gênica , MicroRNAs/genética , Neoplasias Pancreáticas/patologia , Adenocarcinoma/genética , Adenocarcinoma/metabolismo , Carcinoma Ductal Pancreático/genética , Carcinoma Ductal Pancreático/metabolismo , Movimento Celular , Proliferação de Células , Fibroblastos/metabolismo , Humanos , Neoplasias Pancreáticas/genética , Neoplasias Pancreáticas/metabolismo , Tenascina/genética , Tenascina/metabolismo , Fator de Crescimento Transformador beta1/genética , Fator de Crescimento Transformador beta1/metabolismo , Células Tumorais Cultivadas , Neoplasias Pancreáticas
18.
Oncol Lett ; 19(3): 2502-2507, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32194751

RESUMO

HURP gene encodes the hepatoma upregulated protein (HURP), a microtubule associated protein regulating mitotic spindle dynamics, which promotes chromosomal congression and alignment during mitosis, with a potential role in tumorigenesis. In the present study, HURP mRNA expression was investigated by reverse transcription-quantitative PCR in oropharyngeal squamous cell carcinoma (OPSCC). Primary OPSCC tumors from 107 patients and 48 adjacent normal tissues, as well as 12 respiratory tract cancer cell lines (9 head and neck squamous cell carcinoma, 2 lung cancer and 1 normal bronchial) were utilised in the present study. mRNA expression levels of HURP were higher in malignant OPSCC tissues compared with in normal mucosa (P<1×10-5) and significantly associated with sex and smoking status (P<0.0001). Vinorelbine in vitro toxicity at half-maximal inhibitory concentration (IC50) was measured in the 11 cancer cell lines using an MTT assay. Sensitivity to vinorelbine was significantly correlated with HURP expression (r=0.636; P=0.035). The data indicated that HURP overexpression is frequent in OPSCC tissues and associated with smoking. The correlation between HURP mRNA expression and vinorelbine in vitro response suggests that HURP is a potential modulator of vinorelbine response; therefore, it should be explored for its possible predictive value for the efficiency of vinorelbine treatment in this type of cancer.

19.
Br J Cancer ; 122(7): 1050-1058, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32020063

RESUMO

BACKGROUND: Long non-coding RNAs compose an important level of epigenetic regulation in normal physiology and disease. Despite the plethora of publications of lncRNAs in human cancer, the landscape is still unclear. METHODS: Microarray analysis in 44 NSCLC paired specimens was followed by qPCR-based validation in 29 (technical) and 38 (independent) tissue pairs. Cross-validation of the selected targets was achieved in 850 NSCLC tumours from TCGA datasets. RESULTS: Twelve targets were successfully validated by qPCR (upregulated: FEZF1-AS1, LINC01214, LINC00673, PCAT6, NUTM2A-AS1, LINC01929; downregulated: PCAT19, FENDRR, SVIL-AS1, LANCL1-AS1, ADAMTS9-AS2 and LINC00968). All of them were successfully cross validated in the TCGA datasets. Abnormal DNA methylation was observed in the promoters of FENDRR, FEZF1-AS1 and SVIL-AS1. FEZF1-AS1 and LINC01929 were associated with survival in the TCGA set. CONCLUSIONS: Our study provides through multiple levels of internal and external validation, a comprehensive list of dysregulated lncRNAs in NSCLC. We therefore envisage this dataset to serve as an important source for the lung cancer research community assisting future investigations on the involvement of lncRNAs in the pathogenesis of the disease and providing novel biomarkers for diagnosis, prognosis and therapeutic stratification.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/genética , Neoplasias Pulmonares/genética , RNA Longo não Codificante/genética , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/patologia , Prognóstico
20.
Sci Rep ; 9(1): 11992, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427592

RESUMO

We report changes in the genomic landscape in the development of head and neck squamous cell carcinomas HNSCC from potentially premalignant lesions (PPOLS) to malignancy and lymph node metastases. Likely pathological mutations predominantly involved a relatively small set of genes reported previously (TP53, KMT2D, CDKN2A, PIK3CA, NOTCH1 and FAT1) but also other predicted cancer drivers (MGA, PABPC3, NR4A2, NCOR1 and MACF1). Notably, all these mutations arise early and are present in PPOLs. The most frequent genetic changes, which follow acquisition of immortality and loss of senescence, are of consistent somatic copy number alterations (SCNAs) involving chromosomal regions enriched for genes in known and previously unreported cancer-related pathways. We mapped the evolution of SCNAs in HNSCC progression. One of the earliest SCNAs involved deletions of CSMD1 (8p23.2). CSMD1 deletions or promoter hypermethylation were present in all of the immortal PPOLs and occurred at high frequency in the immortal HNSCC cell lines. Modulation of CSMD1 in cell lines revealed significant suppression of proliferation and invasion by forced expression, and significant stimulation of invasion by knockdown of expression. Known cancer drivers NOTCH1, PPP6C, RAC1, EIF4G1, PIK3CA showed significant increase in frequency of SCNA in transition from PPOLs to HNSCC that correlated with their expression. In the later stages of progression, HNSCC with and without nodal metastases showed some clear differences including high copy number gains of CCND1, hsa-miR-548k and TP63 in the metastases group.


Assuntos
Transformação Celular Neoplásica , Neoplasias de Cabeça e Pescoço/etiologia , Neoplasias de Cabeça e Pescoço/patologia , Biomarcadores , Transformação Celular Neoplásica/genética , Transformação Celular Neoplásica/metabolismo , Senescência Celular/genética , Mapeamento Cromossômico , Biologia Computacional/métodos , Variações do Número de Cópias de DNA , Progressão da Doença , Suscetibilidade a Doenças , Perfilação da Expressão Gênica , Instabilidade Genômica , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Queratinócitos/metabolismo , Queratinócitos/patologia , Mutação , Estadiamento de Neoplasias , Carcinoma de Células Escamosas de Cabeça e Pescoço/etiologia , Carcinoma de Células Escamosas de Cabeça e Pescoço/metabolismo , Carcinoma de Células Escamosas de Cabeça e Pescoço/patologia
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