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1.
Br J Biomed Sci ; 81: 12054, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38952614

RESUMO

The peer review process is a fundamental aspect of modern scientific paper publishing, underpinning essential quality control. First conceptualised in the 1700s, it is an iterative process that aims to elevate scientific literature to the highest standards whilst preventing publication of scientifically unsound, potentially misleading, and even plagiarised information. It is widely accepted that the peer review of scientific papers is an irreplaceable and fundamental aspect of the research process. However, the rapid growth of research and technology has led to a huge increase in the number of publications. This has led to increased pressure on the peer review system. There are several established peer review methodologies, ranging from single and double blind to open and transparent review, but their implementation across journals and research fields varies greatly. Some journals are testing entirely novel approaches (such as collaborative reviews), whilst others are piloting changes to established methods. Given the unprecedented growth in publication numbers, and the ensuing burden on journals, editors, and reviewers, it is imperative to improve the quality and efficiency of the peer review process. Herein we evaluate the peer review process, from its historical origins to current practice and future directions.


Assuntos
Revisão da Pesquisa por Pares , Humanos , Pesquisa Biomédica/tendências , Pesquisa Biomédica/normas , História do Século XXI , Revisão da Pesquisa por Pares/tendências , Revisão da Pesquisa por Pares/normas , Publicações Periódicas como Assunto , Editoração/normas , Editoração/tendências , Controle de Qualidade
2.
Transl Oncol ; 46: 102030, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38870677

RESUMO

Following infection or exposure to therapeutic agents, an aggressive immune response may result, termed cytokine storm (CS) or cytokine release syndrome. Here the innate immune system becomes uncontrolled, leading to serious consequences including possible death. Patients surviving CS are at greater risk for de novo tumorigenesis, but it is unclear if any specific cytokines are directly responsible for this outcome. De novo tumorigenesis has been observed in donated cells exposed to CS following haematopoietic stem cell transplant (HSCT). Modelling HSCT, we firstly demonstrated the release of CS levels from the HS-5 human bone marrow stromal cell line, post-exposure to chemotherapy. We then exposed the TK6 lymphoblast cell line to healthy and storm doses of IL-6 and measured increased genotoxicity via the micronucleus assay. During HSCT, haematopoietic cells are exposed to a complex mix of cytokines, so to determine if IL-6 was integral in a chemotherapy-induced bystander effect, we attempted to inhibit IL-6 from HS-5 cells using resatorvid or siRNA, treated with chlorambucil or mitoxantrone, and then co-cultured with bystander TK6 cells. Whilst resatorvid did not reduce IL-6 and did not reduce micronuclei in the bystander TK6 cells, siRNA inhibition reduced IL-6 to healthy in vivo levels, and micronuclei aligned with untreated controls. Our data suggests that exposure to high IL-6 (in the absence of inflammatory cells) has potential to induce genetic damage and may contribute to de novo tumorigenesis post-CS. We suggest that for individuals with a pro-inflammatory profile, anti-IL-6 therapy may be an appropriate intervention to prevent complications post-CS.

3.
Front Endocrinol (Lausanne) ; 15: 1422599, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38832352

RESUMO

RNA biology has revolutionized cancer understanding and treatment, especially in endocrine-related malignancies. This editorial highlights RNA's crucial role in cancer progression, emphasizing its influence on tumor heterogeneity and behavior. Processes like alternative splicing and noncoding RNA regulation shape cancer biology, with microRNAs, long noncoding RNAs, and circular RNAs orchestrating gene expression dynamics. Aberrant RNA signatures hold promise as diagnostic and prognostic biomarkers in endocrine-related cancers. Recent findings, such as aberrant PI3Kδ splice isoforms and epithelial-mesenchymal transition-related lncRNA signatures, unveil potential therapeutic targets for personalized treatments. Insights into m6A-associated lncRNA prognostic models and the function of lncRNA LINC00659 in gastric cancer represents ongoing research in this field. As understanding of RNA's role in cancer expands, personalized therapies offer transformative potential in managing endocrine-related malignancies. This signifies a significant stride towards precision oncology, fostering innovation for more effective cancer care.


Assuntos
Neoplasias , Humanos , Neoplasias/genética , Neoplasias/terapia , Regulação Neoplásica da Expressão Gênica , RNA Longo não Codificante/genética , Biomarcadores Tumorais/genética , MicroRNAs/genética , Medicina de Precisão/métodos , RNA/genética , RNA Circular/genética , Animais
4.
Int J Mol Sci ; 25(10)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38791418

RESUMO

In a screen of over 200 novel pyrazole compounds, ethyl 1-(2-hydroxypentyl)-5-(3-(3-(trifluoromethyl) phenyl)ureido)-1H-pyrazole-4-carboxylate (named GeGe-3) has emerged as a potential anticancer compound. GeGe-3 displays potent anti-angiogenic properties through the presumptive targeting of the protein kinase DMPK1 and the Ca2+-binding protein calreticulin. We further explored the anticancer potential of GeGe-3 on a range of established cancer cell lines, including PC3 (prostate adenocarcinoma), SKMEL-28 (cutaneous melanoma), SKOV-3 (ovarian adenocarcinoma), Hep-G2 (hepatocellular carcinoma), MDA-MB231, SKBR3, MCF7 (breast adenocarcinoma), A549 (lung carcinoma), and HeLa (cervix epithelioid carcinoma). At concentrations in the range of 10 µM, GeGe-3 significantly restricted cell proliferation and metabolism. GeGe-3 also reduced PC3 cell migration in a standard wound closure and trans-well assay. Together, these results confirm the anticancer potential of GeGe-3 and underline the need for more detailed pre-clinical investigations into its molecular targets and mechanisms of action.


Assuntos
Antineoplásicos , Movimento Celular , Proliferação de Células , Pirazóis , Humanos , Pirazóis/farmacologia , Pirazóis/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Ureia/farmacologia , Ureia/química , Ureia/análogos & derivados
5.
Oncogene ; 42(38): 2783-2800, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37587333

RESUMO

To date, thousands of highly abundant and conserved single-stranded RNA molecules shaped into ring structures (circRNAs) have been identified. CircRNAs are multifunctional molecules that have been shown to regulate gene expression transcriptionally and post-transcriptionally and exhibit distinct tissue- and development-specific expression patterns associated with a variety of normal and disease conditions, including cancer pathogenesis. Over the past years, due to their intrinsic stability and resistance to ribonucleases, particular attention has been drawn to their use as reliable diagnostic and prognostic biomarkers in cancer diagnosis, treatment, and prevention. However, there are some critical caveats to their utility in the clinic. Their circular shape limits their annotation and a complete functional elucidation is lacking. This makes their detection and biomedical application still challenging. Herein, we review the current knowledge of circRNA biogenesis and function, and of their involvement in tumorigenesis and potential utility in cancer-targeted therapy.


Assuntos
Neoplasias , RNA Circular , Humanos , RNA Circular/genética , Neoplasias/genética , Carcinogênese , RNA/genética , Transformação Celular Neoplásica
6.
Br J Biomed Sci ; 80: 11041, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36895328

RESUMO

Introduction: Dysregulated alternative splicing is a prominent feature of cancer. The inhibition and knockdown of the SR splice factor kinase SRPK1 reduces tumour growth in vivo. As a result several SPRK1 inhibitors are in development including SPHINX, a 3-(trifluoromethyl)anilide scaffold. The objective of this study was to treat two leukaemic cell lines with SPHINX in combination with the established cancer drugs azacitidine and imatinib. Materials and Methods: We selected two representative cell lines; Kasumi-1, acute myeloid leukaemia, and K562, BCR-ABL positive chronic myeloid leukaemia. Cells were treated with SPHINX concentrations up to 10µM, and in combination with azacitidine (up to 1.5 µg/ml, Kasumi-1 cells) and imatinib (up to 20 µg/ml, K562 cells). Cell viability was determined by counting the proportion of live cells and those undergoing apoptosis through the detection of activated caspase 3/7. SRPK1 was knocked down with siRNA to confirm SPHINX results. Results: The effects of SPHINX were first confirmed by observing reduced levels of phosphorylated SR proteins. SPHINX significantly reduced cell viability and increased apoptosis in Kasumi-1 cells, but less prominently in K562 cells. Knockdown of SRPK1 by RNA interference similarly reduced cell viability. Combining SPHINX with azacitidine augmented the effect of azacitidine in Kasumi-1 cells. In conclusion, SPHINX reduces cell viability and increases apoptosis in the acute myeloid leukaemia cell line Kasumi-1, but less convincingly in the chronic myeloid leukaemia cell line K562. Conclusion: We suggest that specific types of leukaemia may present an opportunity for the development of SRPK1-targeted therapies to be used in combination with established chemotherapeutic drugs.


Assuntos
Antineoplásicos , Leucemia Mielogênica Crônica BCR-ABL Positiva , Leucemia Mieloide Aguda , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/uso terapêutico , Apoptose/genética , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Resistencia a Medicamentos Antineoplásicos/genética , Mesilato de Imatinib/farmacologia , Mesilato de Imatinib/uso terapêutico , Leucemia Mielogênica Crônica BCR-ABL Positiva/tratamento farmacológico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/patologia , Leucemia Mieloide Aguda/tratamento farmacológico , Leucemia Mieloide Aguda/genética , Proteínas Serina-Treonina Quinases/farmacologia , Proteínas Serina-Treonina Quinases/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica
7.
Noncoding RNA ; 7(2)2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-33946639

RESUMO

The discovery of thousands of non-coding RNAs (ncRNAs) pervasively transcribed from the eukaryotic genome has revolutionized the "central dogma" of biology and shifted the attention on the role of RNAs as regulatory molecules, more than simply traditional mediators of genomic information [...].

8.
Noncoding RNA ; 7(1)2021 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-33799493

RESUMO

Alternative splicing is a highly fine-tuned regulated process and one of the main drivers of proteomic diversity across eukaryotes. The vast majority of human multi-exon genes is alternatively spliced in a cell type- and tissue-specific manner, and defects in alternative splicing can dramatically alter RNA and protein functions and lead to disease. The eukaryotic genome is also intensively transcribed into long and short non-coding RNAs which account for up to 90% of the entire transcriptome. Over the years, lncRNAs have received considerable attention as important players in the regulation of cellular processes including alternative splicing. In this review, we focus on recent discoveries that show how lncRNAs contribute significantly to the regulation of alternative splicing and explore how they are able to shape the expression of a diverse set of splice isoforms through several mechanisms. With the increasing number of lncRNAs being discovered and characterized, the contribution of lncRNAs to the regulation of alternative splicing is likely to grow significantly.

9.
Sci Rep ; 11(1): 7963, 2021 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-33846420

RESUMO

Dysregulation of alternative splicing is a feature of cancer, both in aetiology and progression. It occurs because of mutations in splice sites or sites that regulate splicing, or because of the altered expression and activity of splice factors and of splice factor kinases that regulate splice factor activity. Recently the CDC2-like kinases (CLKs) have attracted attention due to their increasing involvement in cancer. We measured the effect of the CLK inhibitor, the benzothiazole TG003, on two prostate cancer cell lines. TG003 reduced cell proliferation and increased apoptosis in PC3 and DU145 cells. Conversely, the overexpression of CLK1 in PC3 cells prevented TG003 from reducing cell proliferation. TG003 slowed scratch closure and reduced cell migration and invasion in a transwell assay. TG003 decisively inhibited the growth of a PC3 cell line xenograft in nude mice. We performed a transcriptomic analysis of cells treated with TG003. We report widespread and consistent changes in alternative splicing of cancer-associated genes including CENPE, ESCO2, CKAP2, MELK, ASPH and CD164 in both HeLa and PC3 cells. Together these findings suggest that targeting CLKs will provide novel therapeutic opportunities in prostate cancer.


Assuntos
Quinases Ciclina-Dependentes/antagonistas & inibidores , Terapia de Alvo Molecular , Neoplasias da Próstata/tratamento farmacológico , Inibidores de Proteínas Quinases/uso terapêutico , Processamento Alternativo/genética , Animais , Apoptose/efeitos dos fármacos , Benzotiazóis/farmacologia , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Proliferação de Células/efeitos dos fármacos , Quinases Ciclina-Dependentes/química , Quinases Ciclina-Dependentes/genética , Quinases Ciclina-Dependentes/metabolismo , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Técnicas de Silenciamento de Genes , Humanos , Masculino , Camundongos Nus , Invasividade Neoplásica , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Inibidores de Proteínas Quinases/farmacologia , RNA-Seq , Tiazóis/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
10.
Cancer Inform ; 19: 1176935120972383, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33239858

RESUMO

Aberrant activation of the WNT/CTNNB1 pathway is notorious in colorectal cancer (CRC). Here, we demonstrate that the expression of specific and crucial WNT signaling pathway genes is linked to disease progression in colonic adenomatous (AP) and hyperplastic (HP) polyps in an Iranian patient population. Thus, we highlight potential gene expression profiles as candidate novel biomarkers for the early detection of CRC. From a 12-month study (2016-2017), 44 biopsy samples were collected during colonoscopy from the patients with colorectal polyps and 10 healthy subjects for normalization. Clinical and demographic data were collected in all cases, and mRNA expression of APC, CTNNB1, CDH1, AXIN1, and AXIN2 genes was investigated using real-time polymerase chain reaction (PCR). CTNNB1 and CDH1 expression levels were unaltered in AP and HP subjects, whereas mRNA expression of APC was decreased in AP contrasted with HP subjects, with a significant association between APC downregulation and polyp size. Although AXIN1 showed no changes between AP and HP groups, a significant association between AXIN1 and dysplasia grade was found. Also, significant upregulation of AXIN2 in both AP and HP subjects was detected. In summary, we have shown increased expression of AXIN2 and decreased expression of APC correlating with grade of dysplasia and polyp size. Hence, AXIN2 and APC should be explored as biomarker candidates for early detection of AP and HP polyps in CRC.

11.
Biochim Biophys Acta Gene Regul Mech ; 1863(12): 194642, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33017668

RESUMO

Dysregulated alternative splicing plays a prominent role in all hallmarks of cancer. The splice factor kinase SRPK1 drives the activity of oncogenic splice factors such as SRSF1. SRSF1 in turn promotes the expression of splice isoforms that favour tumour growth, including proangiogenic VEGF. Knockdown (with siRNA) or chemical inhibition (using SPHINX) of SRPK1 in K562 leukemia and PC3 prostate cancer cell lines reduced cell proliferation, invasion and migration. In glomerular podocytes, the Wilms tumour suppressor zinc-finger transcription factor WT1 represses SRPK1 transcription. Here we show that in cancer cells WT1 activates SRPK1 transcription, unless a canonical WT1 binding site adjacent to the transcription start site is mutated. The ability of WT1 to activate SRPK1 transcription was reversed by the transcriptional corepressor BASP1, and both WT1 and BASP1 co-precipitated with the SRPK1 promoter. BASP1 significantly increased the expression of the antiangiogenic VEGF165b splice isoform. We propose that by upregulating SRPK1 transcription WT1 can direct an alternative splicing landscape that facilitates tumour growth.


Assuntos
Proteínas de Membrana/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Proteínas WT1/metabolismo , Sítios de Ligação , Movimento Celular , Proliferação de Células , Regulação Neoplásica da Expressão Gênica , Humanos , Células K562 , Masculino , Células PC-3 , Regiões Promotoras Genéticas , Isoformas de Proteínas/metabolismo , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Proteínas Serina-Treonina Quinases/genética , Interferência de RNA , Fator A de Crescimento do Endotélio Vascular/metabolismo , Proteínas WT1/antagonistas & inibidores , Proteínas WT1/genética
12.
Br J Cancer ; 123(6): 1024-1032, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32581342

RESUMO

BACKGROUND: The ERG oncogene, a member of the ETS family of transcription factor encoding genes, is a genetic driver of prostate cancer. It is activated through a fusion with the androgen-responsive TMPRSS2 promoter in 50% of cases. There is therefore significant interest in developing novel therapeutic agents that target ERG. We have taken an antisense approach and designed morpholino-based oligonucleotides that target ERG by inducing skipping of its constitutive exon 4. METHODS: We designed antisense morpholino oligonucleotides (splice-switching oligonucleotides, SSOs) that target both the 5' and 3' splice sites of ERG's exon 4. We tested their efficacy in terms of inducing exon 4 skipping in two ERG-positive cell lines, VCaP prostate cancer cells and MG63 osteosarcoma cells. We measured their effect on cell proliferation, migration and apoptosis. We also tested their effect on xenograft tumour growth in mice and on ERG protein expression in a human prostate cancer radical prostatectomy sample ex vivo. RESULTS: In VCaP cells, both SSOs were effective at inducing exon 4 skipping, which resulted in a reduction of overall ERG protein levels up to 96 h following a single transfection. SSO-induced ERG reduction decreased cell proliferation, cell migration and significantly increased apoptosis. We observed a concomitant reduction in protein levels for cyclin D1, c-Myc and the Wnt signalling pathway member ß-catenin as well as a marker of activated Wnt signalling, p-LRP6. We tested the 3' splice site SSO in MG63 xenografts in mice and observed a reduction in tumour growth. We also demonstrated that the 3' splice site SSO caused a reduction in ERG expression in a patient-derived prostate tumour tissue cultured ex vivo. CONCLUSIONS: We have successfully designed and tested morpholino-based SSOs that cause a marked reduction in ERG expression, resulting in decreased cell proliferation, a reduced migratory phenotype and increased apoptosis. Our initial tests on mouse xenografts and a human prostate cancer radical prostatectomy specimen indicate that SSOs can be effective for oncogene targeting in vivo. As such, this study encourages further in vivo therapeutic studies using SSOs targeting the ERG oncogene.


Assuntos
Oligonucleotídeos Antissenso/uso terapêutico , Oncogenes , Neoplasias da Próstata/tratamento farmacológico , Animais , Linhagem Celular Tumoral , Éxons , Masculino , Camundongos , Neoplasias da Próstata/patologia , Serina Endopeptidases/genética , Regulador Transcricional ERG/análise , Regulador Transcricional ERG/antagonistas & inibidores , Regulador Transcricional ERG/genética , Via de Sinalização Wnt , Ensaios Antitumorais Modelo de Xenoenxerto
13.
Cell Oncol (Dordr) ; 42(6): 815-828, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31376137

RESUMO

PURPOSE: Isothiocyanates elicit anticancer effects by targeting cancer stem cells (CSCs). Here, we tested the antitumor activity of phenethyl-isothiocyanate (PEITC), either alone or in combination with trastuzumab, in HER2-positive tumor models. METHODS: We assessed the in vitro anticancer activity of PEITC, alone or combined with trastuzumab, in HER2-positive BT474, SKBR3, HCC1954 and SKOV3 cancer cells by measuring their sphere forming efficiency (SFE). The expression of the human/rodent CSC biomarkers aldehyde-dehydrogenase (ALDH) and CD29High/CD24+/Sca1Low was evaluated by cytofluorimetric analysis. The expression of wild type HER2 (WTHER2), its splice variant d16HER2 and NOTCH was analysed by quantitative RT-PCR and Western blotting. The in vivo activity of PEITC and trastuzumab was evaluated in mice orthotopically implanted with MI6 tumor cells transgenic for the human d16HER2 splice isoform. Magnetic resonance imaging/spectroscopy and immunohistochemistry were used to assess morpho-functional and metabolic profiles of treated versus untreated mice. RESULTS: We found that PEITC significantly impaired the SFE of HER2-positive human cancer cells by decreasing their ALDH-positive compartments. The anti-CSC activity of PEITC was demonstrated by a reduced expression/activation of established cancer-stemness biomarkers. Similar results were obtained with MI6 cells, where PEITC, alone or in combination with trastuzumab, significantly inhibited their SFE. We also found that PEITC hampered the in vivo growth of MI6 nodules by inducing hemorrhagic and necrotic intra-tumor areas and, in combination with trastuzumab, by significantly reducing spontaneous tumor development in d16HER2 transgenic mice. CONCLUSIONS: Our results indicate that PEITC targets HER2-positive CSCs and that its combination with trastuzumab may pave the way for a novel therapeutic strategy for HER2-positive tumors.


Assuntos
Neoplasias da Mama/patologia , Isotiocianatos/farmacologia , Células-Tronco Neoplásicas/patologia , Neoplasias Ovarianas/patologia , Receptor ErbB-2/metabolismo , Animais , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Feminino , Humanos , Camundongos Transgênicos , Proteínas de Neoplasias/metabolismo , Células-Tronco Neoplásicas/efeitos dos fármacos , Neoplasias Ovarianas/metabolismo , Transdução de Sinais/efeitos dos fármacos , Trastuzumab/farmacologia
14.
Sci Rep ; 9(1): 12063, 2019 08 19.
Artigo em Inglês | MEDLINE | ID: mdl-31427663

RESUMO

The phytohormone abscisic acid (ABA) plays a role in stresses that alter plant water status and may also regulate root gravitropism and hydrotropism. ABA also exists in the aquatic algal progenitors of land plants, but other than its involvement in stress responses, its physiological role in these microorganisms remains elusive. We show that exogenous ABA significantly altered the HCO3- uptake of Chamydomonas reinhardtii in a light-intensity-dependent manner. In high light ABA enhanced HCO3- uptake, while under low light uptake was diminished. In the dark, ABA induced a negative geotropic movement of the algae to an extent dependent on the time of sampling during the light/dark cycle. The algae also showed a differential, light-dependent directional taxis response to a fixed ABA source, moving horizontally towards the source in the light and away in the dark. We conclude that light and ABA signal competitively in order for algae to position themselves in the water column to minimise photo-oxidative stress and optimise photosynthetic efficiency. We suggest that the development of this response mechanism in motile algae may have been an important step in the evolution of terrestrial plants and that its retention therein strongly implicates ABA in the regulation of their relevant tropisms.


Assuntos
Ácido Abscísico/metabolismo , Chlamydomonas reinhardtii/metabolismo , Gravitropismo/fisiologia , Reguladores de Crescimento de Plantas/metabolismo , Arabidopsis/metabolismo , Arabidopsis/fisiologia , Chlamydomonas reinhardtii/fisiologia , Clorófitas/metabolismo , Clorófitas/fisiologia , Luz , Fotoperíodo , Transdução de Sinais/genética , Estresse Fisiológico/fisiologia , Água/química
15.
Cancers (Basel) ; 11(7)2019 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-31261614

RESUMO

Human epidermal growth factor receptor 2 (ERBB2 or HER2) amplification/overexpression is associated with a particularly aggressive molecular subtype of breast cancer (BC), characterized by a poor prognosis, increased metastatic potential, and disease recurrence. As only approximately 50% of HER2-positive patients respond to HER2-targeted therapies, greater knowledge of the biology of HER2 and the mechanisms that underlie drug susceptibility is needed to improve cure rates. Evidence suggests that the coexistence of full-length, wild-type HER2 (wtHER2) and altered forms of HER2-such as carboxy-terminus-truncated fragments, activating mutations, and splice variants-significantly increases the heterogeneity of HER2-positive disease, affecting its biology, clinical course, and treatment response. In particular, expression of the d16HER2 splice variant in human HER2-positive BC has a crucial pathobiological function, wherein the absence of sixteen amino acids from the extracellular domain induces the formation of stable and constitutively active HER2 homodimers on the tumor cell surface. Notably, the d16HER2 variant significantly influences the initiation and aggressiveness of tumors, cancer stem cell properties, epithelial-mesenchymal transition (EMT), and the susceptibility of HER2-positive BC cells to trastuzumab compared with its wtHER2 counterpart, thus constituting a novel and potentially clinically useful biomarker. The aims of this review are to summarize the existing evidence regarding the pathobiological functions of the d16HER2 variant and discuss its current and future value with regard to risk assessment and treatment choices in HER2-positive disease.

16.
Methods Mol Biol ; 1990: 27-42, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148060

RESUMO

The modification of proteins is a key way to alter their activity and function. Often thiols, cysteine residues, on proteins are attractive targets for such modification. Assuming that the thiol group is accessible then reactions may take place with a range of chemicals found in cells. These may include reactive oxygen species (ROS), such as hydrogen peroxide (H2O2), reactive nitrogen species such as nitric oxide (NO), hydrogen sulfide (H2S), or glutathione. Such modifications often are instrumental to important cellular signaling processes, which ultimately result in modification of physiology of the organism. Therefore, there is a need to be able to identify such modifications. There are a variety of techniques to find proteins which may be altered in this way but here the focus is on two approaches: firstly, the use of fluorescent thiol derivatives and the subsequent use of mass spectrometry to identify the thiols involved; secondly the confirmation of such changes using biochemical assays and genetic mutants. The discussion will be based on the use of two model organisms: firstly the plant Arabidopsis thaliana (both as cell cultures and whole plants) and secondly the nematode worm Caenorhabditis elegans. However, these tools, as described, may be used in a much wider range of biological systems, including human and human tissue cultures.


Assuntos
Proteínas de Arabidopsis/química , Arabidopsis/metabolismo , Proteínas de Caenorhabditis elegans/química , Caenorhabditis elegans/metabolismo , Sulfeto de Hidrogênio/farmacologia , Espécies Reativas de Nitrogênio/farmacologia , Espécies Reativas de Oxigênio/farmacologia , Poluentes Atmosféricos/farmacologia , Animais , Arabidopsis/efeitos dos fármacos , Arabidopsis/crescimento & desenvolvimento , Proteínas de Arabidopsis/metabolismo , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/crescimento & desenvolvimento , Proteínas de Caenorhabditis elegans/metabolismo , Processamento de Proteína Pós-Traducional , Compostos de Sulfidrila/química
17.
Methods Mol Biol ; 1990: 109-133, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31148067

RESUMO

A hypoxic environment can be defined as a region of the body or the whole body that is deprived of oxygen. Hypoxia is a feature of many diseases, such as cardiovascular disease, tissue trauma, stroke, and solid cancers. A loss of oxygen supply usually results in cell death; however, when cells gradually become hypoxic, they may survive and continue to thrive as described for conditions that promote metastatic growth. The role of hypoxia in these pathogenic pathways is therefore of great interest, and understanding the effect of hypoxia in regulating these mechanisms is fundamentally important. This chapter gives an extensive overview of these mechanisms. Moreover, given the challenges posed by tumor hypoxia we describe the current methods to simulate and detect hypoxic conditions followed by a discussion on current and experimental therapies that target hypoxic cells.


Assuntos
Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Hipóxia/fisiopatologia , Neoplasias/patologia , Oxigênio/análise , Espécies Reativas de Oxigênio/metabolismo , Biomarcadores Tumorais/metabolismo , Humanos , Neoplasias/metabolismo , Neoplasias/terapia , Oxigênio/metabolismo
18.
Cells ; 8(1)2019 01 11.
Artigo em Inglês | MEDLINE | ID: mdl-30641926

RESUMO

Angiogenesis is one hallmark of cancer. Vascular endothelial growth factor (VEGF) is a known inducer of angiogenesis. Many patients benefit from antiangiogenic therapies, which however have limitations. Although VEGF is overexpressed in most tumors, different VEGF isoforms with distinct angiogenic properties are produced through alternative splicing. In podocytes, the Wilms' tumor suppressor 1 (WT1) suppresses the Serine/arginine-rich protein-specific splicing factor kinase (SRPK1), and indirectly Serine/arginine-rich splicing factor 1 (Srsf1) activity, and alters VEGF splicing. We analyzed VEGF isoforms, Wt1, Srpk1, and Srsf1 in normal and tumor endothelium. Wt1, Srpk1, Srsf1, and the angiogenic VEGF164a isoform were highly expressed in tumor endothelium compared to normal lung endothelium. Nuclear expression of Srsf1 was detectable in the endothelium of various tumor types, but not in healthy tissues. Inducible conditional vessel-specific knockout of Wt1 reduced Wt1, Srpk1, and Srsf1 expression in endothelial cells and induced a shift towards the antiangiogenic VEGF120 isoform. Wt1(-KTS) directly binds and activates both the promoters of Srpk1 and Srsf1 in endothelial cells. In conclusion, Wt1 activates Srpk1 and Srsf1 and induces expression of angiogenic VEGF isoforms in tumor endothelium.


Assuntos
Neoplasias Pulmonares/irrigação sanguínea , Neoplasias Pulmonares/metabolismo , Neovascularização Patológica/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Repressoras/metabolismo , Fatores de Processamento de Serina-Arginina/metabolismo , Fator A de Crescimento do Endotélio Vascular/metabolismo , Processamento Alternativo , Animais , Linhagem Celular Tumoral , Endotélio Vascular/metabolismo , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Serina-Treonina Quinases/genética , Proteínas Repressoras/genética , Fatores de Processamento de Serina-Arginina/genética , Fator A de Crescimento do Endotélio Vascular/genética , Proteínas WT1 , Tumor de Wilms/genética , Tumor de Wilms/metabolismo
19.
Transl Oncol ; 12(1): 134-142, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30296658

RESUMO

The oncogene ERG encodes an ETS family transcription factor and is implicated in blood, vascular, and bone development and in prostate, blood, and bone cancer. The ERG gene is alternatively spliced; of particular interest is its cassette exon 7b which adds 24 amino acids, in frame, to the transcriptional activation domain. Higher exon 7b inclusion rates are associated with increased cell proliferation and advanced prostate cancer. The 24 amino acids encoded by exon 7b show evolutionary conservation from humans to echinoderms, highlighting their functional importance. Throughout evolution, these 24 amino acids are encoded by a distinct short exon. Splice-switching oligonucleotides based on morpholino chemistry were designed to induce skipping of ERG exon 7b in MG63 osteosarcoma and VCaP prostate cancer cells. Induction of exon 7b skipping reduced cell proliferation and invasion, increased apoptosis in vitro, and reduced xenograft growth in vivo. We also show that ERG's exon 7b is required for the induction of tissue nonspecific alkaline phosphatase. Together, these findings show that the evolutionarily conserved cassette exon 7b is central to ERG's oncogenic properties.

20.
Gene ; 670: 46-54, 2018 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-29802995

RESUMO

Alternative splicing is a key process required for the regulation of gene expression in normal development and physiology. It is regulated by splice factors whose activities are in turn regulated by splice factor kinases and phosphatases. The CDC-like protein kinases are a widespread family of splice factor kinases involved in normal physiology and in several diseases including cancer. In humans they include the CLK1, CLK2, CLK3 and CLK4 genes. The expression of CLK1 is regulated through alternative splicing producing both full-length catalytically active and truncated catalytically inactive isoforms, CLKT1 (arising from exon 4 skipping) and CLKT2 (arising from intron 4 retention). We examined CLK1 alternative splicing in a range of cancer cell lines, and report widespread and highly variable rates of exon 4 skipping and intron 4 retention. We also examined the effect of severe environmental stress including heat shock, osmotic shock, and exposure to the alkaloid drug harmine on CLK1 alternative splicing in DU145 prostate cancer cells. All treatments rapidly reduced exon 4 skipping and intron 4 retention, shifting the balance towards full-length CLK1 expression. We also found that the inhibition of CLK1 with the benzothiazole TG003 reduced exon 4 skipping and intron 4 retention suggesting an autoregulatory mechanism. CLK1 inhibition with TG003 also resulted in modified alternative splicing of five cancer-associated genes.


Assuntos
Processamento Alternativo , Neoplasias/genética , Proteínas Serina-Treonina Quinases/genética , Proteínas Tirosina Quinases/genética , Estresse Fisiológico , Tiazóis/farmacologia , Processamento Alternativo/efeitos dos fármacos , Linhagem Celular Tumoral , Éxons , Regulação da Expressão Gênica , Células HL-60 , Harmina/farmacologia , Homeostase , Temperatura Alta , Humanos , Íntrons , Pressão Osmótica
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