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1.
Br J Haematol ; 204(6): 2264-2274, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38659295

RESUMO

The interaction of acute myeloid leukaemic (AML) blasts with the bone marrow (BM) microenvironment is a major determinant governing disease progression and resistance to treatment. The constitutive expression of E-selectin in the vascular compartment of BM, a key endothelial cell factor, directly mediates chemoresistance via E-selectin ligand/receptors. Despite the success of hypomethylating agent (HMA)-containing regimens to induce remissions in older AML patients, the development of primary or secondary resistance is common. We report that following treatment with 5-azacitidine, promoter regions regulating the biosynthesis of the E-selectin ligands, sialyl Lewis X, become further hypomethylated. The resultant upregulation of these gene products, in particular α(1,3)-fucosyltransferase VII (FUT7) and α(2,3)-sialyltransferase IV (ST3GAL4), likely causes functional E-selectin binding. When combined with the E-selectin antagonist uproleselan, the adhesion to E-selectin is reversed and the survival of mice transplanted with AML cells is prolonged. Finally, we present clinical evidence showing that BM myeloid cells from higher risk MDS and AML patients have the potential to bind E-selectin, and these cells are more abundant in 5-azacitidine-non-responsive patients. The collective data provide a strong rationale to evaluate 5-azacitidine in combination with the E-selectin antagonist, uproleselan, in this patient population.


Assuntos
Azacitidina , Selectina E , Leucemia Mieloide Aguda , Síndromes Mielodisplásicas , Humanos , Selectina E/metabolismo , Leucemia Mieloide Aguda/tratamento farmacológico , Animais , Síndromes Mielodisplásicas/tratamento farmacológico , Camundongos , Azacitidina/farmacologia , Azacitidina/uso terapêutico , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Feminino , Antígeno Sialil Lewis X , Masculino , Fucosiltransferases , Pessoa de Meia-Idade
2.
Clin Epigenetics ; 15(1): 150, 2023 09 13.
Artigo em Inglês | MEDLINE | ID: mdl-37705055

RESUMO

BACKGROUND: Acute myeloid leukaemia (AML) is a deadly disease characterised by the uncontrolled proliferation of immature myeloid cells within the bone marrow. Altered regulation of DNA methylation is an important epigenetic driver of AML, where the hypoxic bone marrow microenvironment can help facilitate leukaemogenesis. Thus, interactions between epigenetic regulation and hypoxia signalling will have important implications for AML development and treatment. MAIN BODY: This review summarises the importance of DNA methylation and the hypoxic bone marrow microenvironment in the development, progression, and treatment of AML. Here, we focus on the role hypoxia plays on signalling and the subsequent regulation of DNA methylation. Hypoxia is likely to influence DNA methylation through altered metabolic pathways, transcriptional control of epigenetic regulators, and direct effects on the enzymatic activity of epigenetic modifiers. DNA methylation may also prevent activation of hypoxia-responsive genes, demonstrating bidirectional crosstalk between epigenetic regulation and the hypoxic microenvironment. Finally, we consider the clinical implications of these interactions, suggesting that reduced cell cycling within the hypoxic bone marrow may decrease the efficacy of hypomethylating agents. CONCLUSION: Hypoxia is likely to influence AML progression through complex interactions with DNA methylation, where the therapeutic efficacy of hypomethylating agents may be limited within the hypoxic bone marrow. To achieve optimal outcomes for AML patients, future studies should therefore consider co-treatments that can promote cycling of AML cells within the bone marrow or encourage their dissociation from the bone marrow.


Assuntos
Metilação de DNA , Leucemia Mieloide Aguda , Humanos , Epigênese Genética , Leucemia Mieloide Aguda/genética , Transdução de Sinais , Hipóxia/genética , Microambiente Tumoral
3.
Sci Rep ; 12(1): 5776, 2022 04 06.
Artigo em Inglês | MEDLINE | ID: mdl-35388081

RESUMO

Global changes in DNA methylation are observed in development and disease, and single-cell analyses are highlighting the heterogeneous regulation of these processes. However, technical challenges associated with single-cell analysis of DNA methylation limit these studies. We present single-cell transposable element methylation sequencing (scTEM-seq) for cost-effective estimation of average DNA methylation levels. By targeting high-copy SINE Alu elements, we achieve amplicon bisulphite sequencing with thousands of loci covered in each scTEM-seq library. Parallel transcriptome analysis is also performed to link global DNA methylation estimates with gene expression. We apply scTEM-seq to KG1a acute myeloid leukaemia (AML) cells, and primary AML cells. Our method reveals global DNA methylation heterogeneity induced by decitabine treatment of KG1a cells associated with altered expression of immune process genes. We also compare global DNA methylation estimates to expression of transposable elements and find a predominance of negative correlations. Finally, we observe co-ordinated upregulation of many transposable elements in a sub-set of decitabine treated cells. By linking global DNA methylation heterogeneity with transcription, scTEM-seq will refine our understanding of epigenetic regulation in cancer and beyond.


Assuntos
Elementos de DNA Transponíveis , Leucemia Mieloide Aguda , Metilação de DNA , Elementos de DNA Transponíveis/genética , Decitabina/farmacologia , Epigênese Genética , Humanos , Leucemia Mieloide Aguda/genética , Análise de Célula Única
4.
Cancers (Basel) ; 12(11)2020 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-33114584

RESUMO

Myelodysplastic syndrome (MDS) is a malignancy that disrupts normal blood cell production and commonly affects our ageing population. MDS patients are diagnosed using an invasive bone marrow biopsy and high-risk MDS patients are treated with hypomethylating agents (HMAs) such as decitabine and azacytidine. However, these therapies are only effective in 50% of patients, and many develop resistance to therapy, often resulting in bone marrow failure or leukemic transformation. Therefore, there is a strong need for less invasive, diagnostic tests for MDS, novel markers that can predict response to therapy and/or patient prognosis to aid treatment stratification, as well as new and effective therapeutics to enhance patient quality of life and survival. Epigenetic modifiers such as DNA methylation, long non-coding RNAs (lncRNAs) and micro-RNAs (miRNAs) are perturbed in MDS blasts and the bone marrow micro-environment, influencing disease progression and response to therapy. This review focusses on the potential utility of epigenetic modifiers in aiding diagnosis, prognosis, and predicting treatment response in MDS, and touches on the need for extensive and collaborative research using single-cell technologies and multi-omics to test the clinical utility of epigenetic markers for MDS patients in the future.

5.
Epigenomics ; 12(13): 1139-1151, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32790506

RESUMO

Cancer is a disease of global epigenetic dysregulation. Mutations in epigenetic regulators are common events in multiple cancer types and epigenetic therapies are emerging as a treatment option in several malignancies. A major challenge for the clinical management of cancer is the heterogeneous nature of this disease. Cancers are composed of numerous cell types and evolve over time. This heterogeneity confounds decisions regarding treatment and promotes disease relapse. The emergence of single-cell epigenomic technologies has introduced the exciting possibility of linking genetic and transcriptional heterogeneity in the context of cancer biology. The next challenge is to leverage these tools for improved patient outcomes. Here we consider how single-cell epigenomic technologies may address the current challenges faced by cancer clinicians.


Assuntos
Epigênese Genética , Epigenômica , Regulação Neoplásica da Expressão Gênica , Neoplasias/genética , Análise de Célula Única , Epigenoma , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Metástase Neoplásica , Neoplasias/terapia
6.
Cancers (Basel) ; 12(4)2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-32224917

RESUMO

Breast cancer is the most commonly diagnosed and the second leading cause of cancer-related mortality among women worldwide. miR-518f-5p has been shown to modulate the expression of the metastasis suppressor CD9 in prostate cancer. However, the role of miR-518f-5p and CD9 in breast cancer is unknown. Therefore, this study aimed to elucidate the role of miR-518f-5p and the mechanisms responsible for decreased CD9 expression in breast cancer, as well as the role of CD9 in de novo tumor formation and metastasis. miR-518f-5p function was assessed using migration, adhesion, and proliferation assays. miR-518f-5p was overexpressed in breast cancer cell lines that displayed significantly lower CD9 expression as well as less endogenous CD9 3'UTR activity, as assessed using qPCR and dual luciferase assays. Transfection of miR-518f-5p significantly decreased CD9 protein expression and increased breast cell migration in vitro. Cd9 deletion in the MMTV/PyMT mouse model impaired tumor growth, but had no effect on tumor initiation or metastasis. Therefore, inhibition of miR-518f-5p may restore CD9 expression and aid in the treatment of breast cancer metastasis.

7.
Mol Biol Rep ; 47(3): 2073-2084, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32065323

RESUMO

Treatment options for pancreatic cancer (PC) are severely limited due to late diagnosis, early metastasis and the inadequacy of chemotherapy and radiotherapy to combat the aggressive biology of the disease. In recent years, plant-derived bioactive compounds have emerged as a source of novel, anti-cancer agents. Used in traditional medicine worldwide, Elaeocarpus species have reported anti-inflammatory, antioxidant and anti-cancer properties. This study aimed to isolate and identify potential anti-PC compounds in the fruit of Elaeocarpus reticulatus Sm. A 50% acetone crude extract significantly decreased the viability of four pancreatic cell lines (≥ 10 µg/mL for BxPC-3 cells) and induced apoptosis in BxPC-3 and HPDE cells. Analysis by HPLC identified the triterpenoid Cucurbitacin I as a likely component of the extract. Furthermore, treatment with Cucurbitacin I significantly reduced the viability of HPDE and BxPC-3 cells, with results comparable to the same concentration of gemcitabine. Interestingly, attempts to isolate bioactive compounds revealed that the crude extract was more effective at reducing PC-cell viability than the fractionated extracts. This study provides initial insight into the bioactive constituents of E. reticulatus fruits.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Apoptose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Elaeocarpaceae/química , Frutas/química , Extratos Vegetais/farmacologia , Antineoplásicos Fitogênicos/química , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Cromatografia Líquida de Alta Pressão , Relação Dose-Resposta a Droga , Humanos , Neoplasias Pancreáticas , Extratos Vegetais/química , Triterpenos/química , Triterpenos/farmacologia
8.
Molecules ; 24(3)2019 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-30709047

RESUMO

Pancreatic cancer (PC) is a complex, heterogeneous disease with a dismal prognosis. Current therapies have failed to improve survival outcomes, urging the need for discovery of novel targeted treatments. Bispidinone derivatives have yet to be investigated as cytotoxic agents against PC cells. The cytotoxic effect of four bispidinone derivatives (BisP1: 1,5-diphenyl-3,7-bis(2-hydroxyethyl)-3,7-diazabicyclo[3.3.1]nonan-9-one; BisP2: 3,7-bis-(2-(S)-amino-4-methylsulfanylbutyryl)-1,5-diphenyl-3,7-diazabicyclo[3.3.1]nonan-9-one dihydrochloride; BisP3: [2-{7-[2-(S)-tert-butoxycarbonylamino-3-(1H-indol-3-yl)-propionyl]-9-oxo-1,5-diphenyl-3,7-diazabicyclo[3.3.1]non-3-yl}-1-(S)-(1H-indol-3-ylmethyl)-2-oxoethyl]-carbamic acid tertbutyl ester; BisP4: 3,7-bis-[2-(S)-amino-3-(1H-indol-3-yl)-propionyl]-1,5-diphenyl-3,7-diazabicyclo[3.3.1]nonan-9-one dihydrochloride) was assessed against PC cell lines (MiaPaca-2, CFPAC-1 and BxPC-3). Cell viability was assessed using a Cell Counting Kit-8 (CCK-8) colorimetric assay, while apoptotic cell death was confirmed using fluorescence microscopy and flow cytometry. Initial viability screening revealed significant cytotoxic activity from BisP4 treatment (1 µM⁻100 µM) on all three cell lines, with IC50 values for MiaPaca-2, BxPC-3, and CFPAC-1 16.9 µM, 23.7 µM, and 36.3 µM, respectively. Cytotoxic treatment time-response (4 h, 24 h, and 48 h) revealed a 24 h treatment time was sufficient to produce a cytotoxic effect on all cell lines. Light microscopy evaluation (DAPI staining) of BisP4 treated MiaPaca-2 PC cells revealed dose-dependent characteristic apoptotic morphological changes. In addition, flow cytometry confirmed BisP4 induced apoptotic cell death induction of activated caspase-3/-7. The bispidinone derivative BisP4 induced an apoptosis-mediated cytotoxic effect on MiaPaca-2 cell lines and significant cytotoxicity on CFPAC-1 and BxPC-3 cell lines. Further investigations into the precise cellular mechanisms of action of this class of compounds are necessary for potential development into pre-clinical trials.


Assuntos
Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/química , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Antineoplásicos/síntese química , Compostos Bicíclicos Heterocíclicos com Pontes/síntese química , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Células Cultivadas , Humanos , Estrutura Molecular , Neoplasias Pancreáticas
9.
Lipids Health Dis ; 17(1): 211, 2018 Sep 08.
Artigo em Inglês | MEDLINE | ID: mdl-30193584

RESUMO

BACKGROUND: Extracellular vesicles (EVs) are produced and secreted from most cells of the body and can be recovered in biological fluids. Although there has been extensive characterisation of the protein and nucleic acid component of EVs, their lipidome has received little attention and may represent a unique and untapped source of biomarkers for prostate cancer diagnosis and prognosis. METHODS: EVs were isolated from non-tumourigenic (RWPE1), tumourigenic (NB26) and metastatic (PC-3) prostate cell lines. Lipids were extracted and subsequently used for targeted lipidomics analysis for the quantitation of molecular lipid species. RESULTS: A total of 187 molecular lipid species were quantitatively identified in EV samples showing differential abundance between RWPE1, NB26 and PC-3 EV samples. Fatty acids, glycerolipids and prenol lipids were more highly abundant in EVs from non-tumourigenic cells, whereas sterol lipids, sphingolipids and glycerophospholipids were more highly abundant in EVs from tumourigenic or metastatic cells. CONCLUSIONS: This study identified differences in the molecular lipid species of prostate cell-derived EVs, increasing our understanding of the changes that occur to the EV lipidome during prostate cancer progression. These differences highlight the importance of characterising the EV lipidome, which may lead to improved diagnostic and prognostic biomarkers for prostate cancer.


Assuntos
Biomarcadores Tumorais/genética , Vesículas Extracelulares/genética , Lipídeos/genética , Neoplasias da Próstata/genética , Biomarcadores Tumorais/metabolismo , Linhagem Celular Tumoral , Vesículas Extracelulares/metabolismo , Humanos , Masculino , Metástase Neoplásica , Prognóstico , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/patologia
10.
Mol Biol Rep ; 45(6): 2125-2133, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30209740

RESUMO

Helicteres hirsuta Lour. (H. hirsuta) has been considered as a herbal medicine for the treatment of malaria and diabetes but limited studies have been conducted on its anticancer and antibacterial properties. In this study, the in vitro antibacterial and anticancer properties of the leaf and stem extracts and their two sub-fractions (aqueous and saponin-enriched butanol fractions) prepared from H. hirsuta were elucidated. MTT and CCK-8 assays were employed to assess their in vitro anticancer properties against various cancer cell lines. The antibacterial activity was assessed using the disc diffusion method and minimum inhibitory concentration (MIC) values were determined. The results revealed that the saponin-enriched fractions from H. hirsuta leaves and stems showed the highest antibacterial activity against E. coli (MIC values of 2.50 and 5.00 mg/mL, respectively) and S. lugdunensis (MIC values of 0.35 and 0.50 mg/mL, respectively). Importantly, these saponin-enriched fractions possessed strong anticancer activity in vitro towards a range of cancer cell lines including MIA PaCa-2 (pancreas); A2780 (ovarian); H460 (lung); A431 (skin); Du145 (prostate); HT29 (colon); MCF-7 (breast); SJ-G2, U87, SMA (glioblastoma) and BE2-C (neuroblastoma) at low doses (GI50 values of 0.36-11.17 µg/mL). They especially revealed potent anti-pancreatic cancer activity in vitro against MIA PaCa-2, BxPC-3 and CFPAC-1 cells with IC50 values of 1.80-6.43 µg/mL. This finding provides scientific evidence of the cytotoxic activity of the extracts prepared from H. hirsuta leaves and stems, and suggests further studies to isolate active compounds for development of new anticancer agents from these plant extracts.


Assuntos
Linhagem Celular Tumoral/efeitos dos fármacos , Malvaceae/química , Malvaceae/metabolismo , Extratos Vegetais/uso terapêutico , Antibacterianos , Anticarcinógenos , Antioxidantes , Escherichia coli/efeitos dos fármacos , Humanos , Malvaceae/genética , Testes de Sensibilidade Microbiana , Fitoterapia/métodos , Folhas de Planta , Caules de Planta , Plantas Medicinais/química , Staphylococcus lugdunensis/efeitos dos fármacos
11.
Int J Mol Sci ; 19(7)2018 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-30004416

RESUMO

Current chemotherapy drugs for pancreatic cancer only offer an increase in survival of up to six months. Additionally, they are highly toxic to normal tissues, drastically affecting the quality of life of patients. Therefore, the search for novel agents, which induce apoptosis in cancer cells while displaying limited toxicity towards normal cells, is paramount. The olive biophenols, oleuropein, hydroxytyrosol and tyrosol, have displayed cytotoxicity towards cancer cells without affecting non-tumorigenic cells in cancers of the breast and prostate. However, their activity in pancreatic cancer has not been investigated. Therefore, the aim of this study was to determine the anti-pancreatic cancer potential of oleuropein, hydroxytyrosol and tyrosol. Pancreatic cancer cells (MIA PaCa-2, BxPC-3, and CFPAC-1) and non-tumorigenic pancreas cells (HPDE) were treated with oleuropein, hydroxytyrosol and tyrosol to determine their effect on cell viability. Oleuropein displayed selective toxicity towards MIA PaCa-2 cells and hydroxytyrosol towards MIA PaCa-2 and HPDE cells. Subsequent analysis of Bcl-2 family proteins and caspase 3/7 activation determined that oleuropein and hydroxytyrosol induced apoptosis in MIA PaCa-2 cells, while oleuropein displayed a protective effect on HPDE cells. Gene expression analysis revealed putative mechanisms of action, which suggested that c-Jun and c-Fos are involved in oleuropein and hydroxytyrosol induced apoptosis of MIA PaCa-2 cells.


Assuntos
Apoptose/efeitos dos fármacos , Ciclo Celular/efeitos dos fármacos , Iridoides/farmacologia , Olea/química , Neoplasias Pancreáticas/tratamento farmacológico , Álcool Feniletílico/análogos & derivados , Proteínas Reguladoras de Apoptose/metabolismo , Linhagem Celular Tumoral , Humanos , Glucosídeos Iridoides , Iridoides/química , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Álcool Feniletílico/química , Álcool Feniletílico/farmacologia
12.
Sci Rep ; 8(1): 8822, 2018 06 11.
Artigo em Inglês | MEDLINE | ID: mdl-29891991

RESUMO

To facilitate intercellular communication, cells release nano-sized, extracellular vesicles (EVs) to transfer biological cargo to both local and distant sites. EVs are enriched in tetraspanins, two of which (CD9 and CD151) have altered expression patterns in many solid tumours, including prostate cancer, as they advance toward metastasis. We aimed to determine whether EVs from prostate cells with altered CD9 and CD151 expression could influence cellular behaviour and increase the metastatic capabilities of non-tumourigenic prostate cells. EVs were isolated by ultrafiltration and characterised for their tetraspanin expression and size distribution. iTRAQ was used to identify differences between RWPE1 and tetraspanin-modified RWPE1 EV proteomes, showing an enrichment in protein degradation pathways. Addition of EVs from RWPE1 cells with reduced CD9 or increased CD151 abundance resulted in increased invasion of RWPE1 cells, and increased migration in the case of high CD151 abundance. We have been able to show that alteration of CD9 and CD151 on prostate cells alters the proteome of their resultant EVs, and that these EVs can enhance the migratory and invasive capabilities of a non-tumourigenic prostate cellular population. This work suggests that cellular tetraspanin levels can alter EVs, potentially acting as a driver of metastasis in prostate cancer.


Assuntos
Movimento Celular , Vesículas Extracelulares/química , Próstata/citologia , Tetraspanina 24/análise , Tetraspanina 29/análise , Linhagem Celular , Humanos , Masculino , Proteoma/análise
13.
Biomed Pharmacother ; 105: 449-460, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29879629

RESUMO

New therapeutic strategies such as the development of novel drugs and combinatorial therapies with existing chemotherapeutic agents are urgently needed to improve the clinical prognosis of pancreatic cancer. We have previously reported the antiproliferative properties of aqueous crude Eucalyptus microcorys extract against pancreatic cancer cell lines. In this study, bioassay-guided fractionation of the aqueous crude E. microcorys extract using RP-HPLC and subsequent assessment of the resultant fractions (F1-F5) for their antioxidant activity and cytotoxicity against pancreatic cancer cell lines were performed. The molecular mechanisms associated with the cytotoxicity was characterised by studying the effects of the most potent fraction-1 (F1) on apoptosis and cell cycle profiles as well as its phytochemical constituents by LC-ESI/MS/MS. F1 displayed significantly greater antioxidant activity in three different assays (p < 0.05). Moreover, F1 exhibited significantly greater antiproliferative activity (IC50 = 93.11 ±â€¯3.43 µg/mL) against MIA PaCa-2 cells compared to the other four fractions (p < 0.05). F1 induced apoptosis by regulating key apoptotic proteins- Bcl-2, Bak, Bax, cleaved PARP, procaspase-3 and cleaved caspase-3 in MIA PaCa-2 cells, suggesting the involvement of intrinsic mitochondrial apoptotic pathway and arrested cells at G2/M phase. A combination of gemcitabine and F1 exerted a greater effect on apoptosis and cell cycle arrest than F1 or gemcitabine alone (p < 0.05). LC-ESI/MS/MS revealed the tentative identities of phytochemicals present in F1 and their similarities with the phenolic compounds previously reported in Eucalyptus with antipancreatic cancer activity. Our study shows that the polyphenol and antioxidant-rich fraction of E. microcorys extract is a promising candidate for developing mono or combination therapies against pancreatic cancer.


Assuntos
Apoptose , Pontos de Checagem do Ciclo Celular , Eucalyptus/química , Neoplasias Pancreáticas/patologia , Extratos Vegetais/química , Folhas de Planta/química , Antioxidantes/farmacologia , Apoptose/efeitos dos fármacos , Proteínas Reguladoras de Apoptose/metabolismo , Ciclo Celular/efeitos dos fármacos , Pontos de Checagem do Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Cromatografia de Fase Reversa , Humanos
14.
Oncotarget ; 9(2): 1980-1991, 2018 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-29416746

RESUMO

Tetraspanin CD9 is generally considered to be a metastasis suppressor, with decreased levels associated with progression and metastasis in many advanced stage cancers. Little is known about the cause of CD9 dysregulation in prostate cancer, however there are several miRNA-binding sites in the 3´UTR of the transcript suggesting it could be post-transcriptionally regulated. Using microarrays and luciferase assays in tumourigenic and non-tumourigenic prostate cell lines we identified miR-518f-5p as a regulator of the CD9 3'UTR gene expression, and decreased expression of endogenous CD9 in non-tumorigenic prostate RWPE1 and prostate cancer DU145 cells. This resulted in differential functional effects, in which RWPE1 cells showed increased migration and decreased adhesion to extracellular matrix substrates, whereas DU145 cells showed decreased migration and increased adhesion. Moreover, overexpression of miR-518f-5p significantly increased proliferation between 48h and 72h in normal RWPE1 cells, with no effect on tumourigenic DU145 cell proliferation. These results show that tetraspanin CD9 is regulated by miRNAs in prostate cell lines and that due to differential functional effects in non-tumourigenic versus tumourigenic prostate cells, miR-518f-5p may be an effective biomarker and/or therapeutic target for prostate cancer progression.

15.
Sci Rep ; 7(1): 15987, 2017 11 22.
Artigo em Inglês | MEDLINE | ID: mdl-29167507

RESUMO

In humans and FVB/N mice, loss of functional tetraspanin CD151 is associated with glomerular disease characterised by early onset proteinuria and ultrastructural thickening and splitting of the glomerular basement membrane (GBM). To gain insight into the molecular mechanisms associated with disease development, we characterised the glomerular gene expression profile at an early stage of disease progression in FVB/N Cd151 -/- mice compared to Cd151 +/+ controls. This study identified 72 up-regulated and 183 down-regulated genes in FVB/N Cd151 -/- compared to Cd151 +/+ glomeruli (p < 0.05). Further analysis highlighted induction of the matrix metalloprotease MMP-10 and the extracellular matrix protein mindin (encoded by Spon2) in the diseased FVB/N Cd151 -/- GBM that did not occur in the C57BL/6 diseased-resistant strain. Interestingly, mindin was also detected in urinary samples of FVB/N Cd151 -/- mice, underlining its potential value as a biomarker for glomerular diseases associated with GBM alterations. Gene set enrichment and pathway analysis of the microarray dataset showed enrichment in axon guidance and actin cytoskeleton signalling pathways as well as activation of inflammatory pathways. Given the known function of mindin, its early expression in the diseased GBM could represent a trigger of both further podocyte cytoskeletal changes and inflammation, thereby playing a key role in the mechanisms of disease progression.


Assuntos
Proteínas da Matriz Extracelular/metabolismo , Glomérulos Renais/metabolismo , Metaloproteinase 10 da Matriz/metabolismo , Tetraspanina 24/deficiência , Animais , Western Blotting , Proteínas da Matriz Extracelular/genética , Masculino , Metaloproteinase 10 da Matriz/genética , Camundongos , Camundongos Endogâmicos C57BL , Reação em Cadeia da Polimerase em Tempo Real , Tetraspanina 24/genética
16.
In Vitro Cell Dev Biol Anim ; 53(7): 604-615, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28452004

RESUMO

In spite of the recent advancements in oncology, the overall survival rate for pancreatic cancer has not improved over the last five decades. Eucalypts have been linked with cytotoxic and anticancer properties in various studies; however, there is very little scientific evidence that supports the direct role of eucalypts in the treatment of pancreatic cancer. This study assessed the anticancer properties of aqueous and ethanolic extracts of four Eucalyptus species using an MTT assay. The most promising extracts were further evaluated using a CCK-8 assay. Apoptotic studies were performed using a caspase 3/7 assay in MIA PaCa-2 cells. The aqueous extract of Eucalyptus microcorys leaf and the ethanolic extract of Eucalyptus microcorys fruit inhibited the growth of glioblastoma, neuroblastoma, lung and pancreatic cancer cells by more than 80% at 100 µg/mL. The E. microcorys and Eucalyptus saligna extracts showed lower GI50 values than the ethanolic Eucalyptus robusta extract in MIA PaCa-2 cells. Aqueous E. microcorys leaf and fruit extracts at 100 µg/mL exerted significantly higher cell growth inhibition in MIA PaCa-2 cells than other extracts (p < 0.05). Statistically similar IC50 values (p > 0.05) were observed in aqueous E. microcorys leaf (86.05 ± 4.75 µg/mL) and fruit (64.66 ± 15.97 µg/mL) and ethanolic E. microcorys leaf (79.30 ± 29.45 µg/mL) extracts in MIA PaCa-2 cells using the CCK-8 assay. Caspase 3/7-mediated apoptosis and morphological changes of cells were also witnessed in MIA PaCa-2 cells after 24 h of treatment with the extracts. This study highlighted the significance of E. microcorys as an important source of phytochemicals with efficacy against pancreatic cancer cells. Further studies are warranted to purify and structurally identify individual compounds and elucidate their mechanisms of action for the development of more potent and specific chemotherapeutic agents for pancreatic cancer.


Assuntos
Antineoplásicos/farmacologia , Eucalyptus/química , Extratos Vegetais/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Forma Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Desoxicitidina/análogos & derivados , Desoxicitidina/farmacologia , Humanos , Concentração Inibidora 50 , Gencitabina
17.
Chem Biodivers ; 14(3)2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27935659

RESUMO

While the pharmacological and toxicological properties of eucalypts are well known in indigenous Australian medicinal practice, investigations of the bioactivity of eucalypt extracts against high mortality diseases such as pancreatic cancer in Western medicine have to date been limited, particularly amongst the genera Corymbia and Angophora. Four Angophora and Corymbia species were evaluated for their phytochemical profile and efficacy against both primary and secondary pancreatic cancer cell lines. The aqueous leaf extract of Angophora hispida exhibited statistically higher total phenolic content (107.85 ± 1.46 mg of gallic acid equiv. per g) and total flavonoid content (57.96 ± 1.93 mg rutin equiv. per g) and antioxidant capacity compared to the other tested eucalypts (P < 0.05). Both A. hispida and A. floribunda aqueous extracts showed statistically similar saponin contents. Angophora floribunda extract exerted significantly greater cell growth inhibition of 77.91 ± 4.93% followed by A. hispida with 62.04 ± 7.47% (P < 0.05) at 100 µg/ml in MIA PaCa-2 cells with IC50 values of 75.58 and 87.28 µg/ml, respectively. More studies are required to isolate and identify the bioactive compounds from these two Angophora species and to determine their mode of action against pancreatic malignancies.


Assuntos
Myrtaceae/química , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Antineoplásicos Fitogênicos/química , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Antioxidantes/química , Austrália , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Humanos , Myrtaceae/metabolismo , Neoplasias Pancreáticas/metabolismo , Neoplasias Pancreáticas/patologia , Compostos Fitoquímicos/isolamento & purificação , Extratos Vegetais/química , Folhas de Planta/química , Folhas de Planta/metabolismo , Saponinas/análise
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