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1.
Int J Mol Sci ; 24(4)2023 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-36835644

RESUMO

In vivo models of acute myeloid leukemia (AML) are low throughput, and standard liquid culture models fail to recapitulate the mechanical and biochemical properties of the extracellular matrix-rich protective bone marrow niche that contributes to drug resistance. Candidate drug discovery in AML requires advanced synthetic platforms to improve our understanding of the impact of mechanical cues on drug sensitivity in AML. By use of a synthetic, self-assembling peptide hydrogel (SAPH) of modifiable stiffness and composition, a 3D model of the bone marrow niche to screen repurposed FDA-approved drugs has been developed and utilized. AML cell proliferation was dependent on SAPH stiffness, which was optimized to facilitate colony growth. Three candidate FDA-approved drugs were initially screened against the THP-1 cell line and mAF9 primary cells in liquid culture, and EC50 values were used to inform drug sensitivity assays in the peptide hydrogel models. Salinomycin demonstrated efficacy in both an 'early-stage' model in which treatment was added shortly after initiation of AML cell encapsulation, and an 'established' model in which time-encapsulated cells had started to form colonies. Sensitivity to Vidofludimus treatment was not observed in the hydrogel models, and Atorvastatin demonstrated increased sensitivity in the 'established' compared to the 'early-stage' model. AML patient samples were equally sensitive to Salinomycin in the 3D hydrogels and partially sensitive to Atorvastatin. Together, this confirms that AML cell sensitivity is drug- and context-specific and that advanced synthetic platforms for higher throughput are valuable tools for pre-clinical evaluation of candidate anti-AML drugs.


Assuntos
Hidrogéis , Leucemia Mieloide Aguda , Humanos , Hidrogéis/uso terapêutico , Atorvastatina/uso terapêutico , Leucemia Mieloide Aguda/metabolismo , Medula Óssea/metabolismo , Peptídeos/uso terapêutico
2.
Sci Rep ; 12(1): 11553, 2022 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-35798820

RESUMO

Polymerase chain reaction (PCR) has proven to be the gold-standard for SARS-CoV-2 detection in clinical settings. The most common approaches rely on nasopharyngeal specimens obtained from swabs, followed by RNA extraction, reverse transcription and quantitative PCR. Although swab-based PCR is sensitive, swabbing is invasive and unpleasant to administer, reducing patient compliance for regular testing and resulting in an increased risk of improper sampling. To overcome these obstacles, we developed a non-invasive one-step RT-qPCR assay performed directly on saliva specimens. The University of Nottingham Asymptomatic Testing Service protocol simplifies sample collection and bypasses the need for RNA extraction, or additives, thus helping to encourage more regular testing and reducing processing time and costs. We have evaluated the assay against the performance criteria specified by the UK regulatory bodies and attained accreditation (BS EN ISO/IEC 17,025:2017) for SARS-CoV-2 diagnostic testing by the United Kingdom Accreditation Service. We observed a sensitivity of 1 viral copy per microlitre of saliva, and demonstrated a concordance of > 99.4% between our results and those of other accredited testing facilities. We concluded that saliva is a stable medium that allows for a highly precise, repeatable, and robust testing method.


Assuntos
COVID-19 , SARS-CoV-2 , COVID-19/diagnóstico , Teste para COVID-19 , Técnicas de Laboratório Clínico/métodos , Humanos , Nasofaringe , RNA Viral/análise , RNA Viral/genética , SARS-CoV-2/genética , Saliva/química , Sensibilidade e Especificidade , Manejo de Espécimes/métodos
3.
Front Oncol ; 12: 840046, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35707351

RESUMO

The protein kinase C (PKC) family of serine/threonine kinases are pleiotropic signaling regulators and are implicated in hematopoietic signaling and development. Only one isoform however, PKCϵ, has oncogenic properties in solid cancers where it is associated with poor outcomes. Here we show that PKCϵ protein is significantly overexpressed in acute myeloid leukemia (AML; 37% of patients). In addition, PKCϵ expression in AML was associated with a significant reduction in complete remission induction and disease-free survival. Examination of the functional consequences of PKCϵ overexpression in normal human hematopoiesis, showed that PKCϵ promotes myeloid differentiation, particularly of the monocytic lineage, and decreased colony formation, suggesting that PKCϵ does not act as an oncogene in hematopoietic cells. Rather, in AML cell lines, PKCϵ overexpression selectively conferred resistance to the chemotherapeutic agent, daunorubicin, by reducing intracellular concentrations of this agent. Mechanistic analysis showed that PKCϵ promoted the expression of the efflux pump, P-GP (ABCB1), and that drug efflux mediated by this transporter fully accounted for the daunorubicin resistance associated with PKCϵ overexpression. Analysis of AML patient samples also showed a link between PKCϵ and P-GP protein expression suggesting that PKCϵ expression drives treatment resistance in AML by upregulating P-GP expression.

4.
Methods Protoc ; 5(2)2022 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-35314662

RESUMO

Since mid-2020 there have been complexities and difficulties in the standardisation and administration of nasopharyngeal swabs. Coupled with the variable and/or poor accuracy of lateral flow devices, this has led to increased societal 'testing fatigue' and reduced confidence in test results. Consequently, asymptomatic individuals have developed reluctance towards repeat testing, which remains the best way to monitor COVID-19 cases in the wider population. On the other hand, saliva-based PCR, a non-invasive, highly sensitive, and accurate test suitable for everyone, is gaining momentum as a straightforward and reliable means of detecting SARS-CoV-2 in symptomatic and asymptomatic individuals. Here, we provide an itemised list of the equipment and reagents involved in the process of sample submission, inactivation and analysis, as well as a detailed description of how each of these steps is performed.

5.
J Med Microbiol ; 70(3)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33734960

RESUMO

Introduction. The COVID-19 pandemic, which began in 2020 is testing economic resilience and surge capacity of healthcare providers worldwide. At the time of writing, positive detection of the SARS-CoV-2 virus remains the only method for diagnosing COVID-19 infection. Rapid upscaling of national SARS-CoV-2 genome testing presented challenges: (1) Unpredictable supply chains of reagents and kits for virus inactivation, RNA extraction and PCR-detection of viral genomes. (2) Rapid time to result of <24 h is required in order to facilitate timely infection control measures.Hypothesis. Extraction-free sample processing would impact commercially available SARS-CoV-2 genome detection methods.Aim. We evaluated whether alternative commercially available kits provided sensitivity and accuracy of SARS-CoV-2 genome detection comparable to those used by regional National Healthcare Services (NHS).Methodology. We tested several detection methods and tested whether detection was altered by heat inactivation, an approach for rapid one-step viral inactivation and RNA extraction without chemicals or kits.Results. Using purified RNA, we found the CerTest VIASURE kit to be comparable to the Altona RealStar system currently in use, and further showed that both diagnostic kits performed similarly in the BioRad CFX96 and Roche LightCycler 480 II machines. Additionally, both kits were comparable to a third alternative using a combination of Quantabio qScript one-step Quantitative Reverse Transcription Polymerase Chain Reaction (qRT-PCR) mix and Centre for Disease Control and Prevention (CDC)-accredited N1 and N2 primer/probes when looking specifically at borderline samples. Importantly, when using the kits in an extraction-free protocol, following heat inactivation, we saw differing results, with the combined Quantabio-CDC assay showing superior accuracy and sensitivity. In particular, detection using the CDC N2 probe following the extraction-free protocol was highly correlated to results generated with the same probe following RNA extraction and reported clinically (n=127; R2=0.9259).Conclusion. Our results demonstrate that sample treatment can greatly affect the downstream performance of SARS-CoV-2 diagnostic kits, with varying impact depending on the kit. We also showed that one-step heat-inactivation methods could reduce time from swab receipt to outcome of test result. Combined, these findings present alternatives to the protocols in use and can serve to alleviate any arising supply-chain issues at different points in the workflow, whilst accelerating testing, and reducing cost and environmental impact.


Assuntos
Teste de Ácido Nucleico para COVID-19 , COVID-19/diagnóstico , SARS-CoV-2/isolamento & purificação , Manejo de Espécimes/métodos , Meios de Cultura , Temperatura Alta , Humanos , RNA Viral/genética , RNA Viral/isolamento & purificação , Kit de Reagentes para Diagnóstico , SARS-CoV-2/genética , Sensibilidade e Especificidade , Inativação de Vírus
6.
EJHaem ; 2(1): 40-47, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35846088

RESUMO

Recent advances in treatment options for multiple myeloma (MM) have positive impact on patient survival. However, there is a short fall of rapid and reliable assays that can predict patient response to novel agents. The anti-apoptotic proteins B-cell lymphoma-2 (BCL-2) and myeloid cell leukaemia-1 (MCL-1), are necessary for MM survival, although most myelomas are more dependent on MCL-1. BCL-2 inhibition alone yields significant cytotoxicity in only a minority of cases, therefore targeting both proteins simultaneously, is a therapeutic option. Venetoclax and S63845 are BCL-2 and MCL-1 targeting BH3-mimetics which have demonstrated apoptotic synergy in MM. We investigated whether a novel short-term flow cytometric cytochrome c release assay could predict response to dual BH3-mimetic targeting in MM cells. Six human myeloma cell lines (HMCL) and seven primary samples were treated with venetoclax and S63845 alone or in combination. The 4-hour assay confirmed the drug combination was synergistic in all HMCL tested. Annexin-V data at 48 hours corresponded with 4-hour response verifying the assay as a predictor of drug sensitivity. All primary samples responded to the drug combination, including samples with 1q gain and t(4;14) translocation. Normal stem cells were unaffected by the drug combination. We have developed a novel assay with the potential to predict response to therapy in MM cells.

7.
Leuk Lymphoma ; 62(2): 281-290, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33021411

RESUMO

Mutations in the highly similar genes B-cell translocation gene 1 (BTG1) and BTG2 are identified in approximately 10-15% of non-Hodgkin lymphoma cases, which may suggest a direct involvement of BTG1 and BTG2 in malignant transformation. However, it is unclear whether or how disease-associated mutations impair the function of these genes. Therefore, we selected 16 BTG1 variants based on in silico analysis. We then evaluated (i) the ability of these variants to interact with the known protein-binding partners CNOT7 and CNOT8, which encode the Caf1 catalytic subunit of the Ccr4-Not deadenylase complex; (ii) the activity of the variant proteins in cell cycle progression; (iii) translational repression; and (iv) mRNA degradation. Based on these analyses, we conclude that mutations in BTG1 may contribute to malignant transformation and tumor cell proliferation by interfering with its anti-proliferative activity and ability to interact with CNOT7 and CNOT8.


Assuntos
Proteínas Imediatamente Precoces , Linfoma não Hodgkin , Proliferação de Células , Exorribonucleases , Humanos , Linfoma não Hodgkin/genética , Proteínas de Neoplasias/genética , Proteínas de Neoplasias/metabolismo , Ligação Proteica , Receptores CCR4 , Proteínas Repressoras , Fatores de Transcrição , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo
8.
BMC Cancer ; 20(1): 629, 2020 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-32635894

RESUMO

BACKGROUND: Acute myeloid leukemia (AML) is a heterogenous hematological malignancy with poor long-term survival. New drugs which improve the outcome of AML patients are urgently required. In this work, the activity and mechanism of action of the cytotoxic indole alkaloid Jerantinine B (JB), was examined in AML cells. METHODS: We used a combination of proliferation and apoptosis assays to assess the effect of JB on AML cell lines and patient samples, with BH3 profiling being performed to identify early effects of the drug (4 h). Phosphokinase arrays were adopted to identify potential driver proteins in the cellular response to JB, the results of which were confirmed and extended using western blotting and inhibitor assays and measuring levels of reactive oxygen species. RESULTS: AML cell growth was significantly impaired following JB exposure in a dose-dependent manner; potent colony inhibition of primary patient cells was also observed. An apoptotic mode of death was demonstrated using Annexin V and upregulation of apoptotic biomarkers (active caspase 3 and cleaved PARP). Using BH3 profiling, JB was shown to prime cells to apoptosis at an early time point (4 h) and phospho-kinase arrays demonstrated this to be associated with a strong upregulation and activation of both total and phosphorylated c-Jun (S63). The mechanism of c-Jun activation was probed and significant induction of reactive oxygen species (ROS) was demonstrated which resulted in an increase in the DNA damage response marker γH2AX. This was further verified by the loss of JB-induced C-Jun activation and maintenance of cell viability when using the ROS scavenger N-acetyl-L-cysteine (NAC). CONCLUSIONS: This work provides the first evidence of cytotoxicity of JB against AML cells and identifies ROS-induced c-Jun activation as the major mechanism of action.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Alcaloides Indólicos/farmacologia , Leucemia Mieloide Aguda/tratamento farmacológico , Proteínas Proto-Oncogênicas c-jun/agonistas , Acetilcisteína/farmacologia , Antineoplásicos Fitogênicos/uso terapêutico , Apoptose/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Dano ao DNA/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Sequestradores de Radicais Livres/farmacologia , Humanos , Alcaloides Indólicos/uso terapêutico , Leucemia Mieloide Aguda/patologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-jun/metabolismo , Espécies Reativas de Oxigênio/antagonistas & inibidores , Espécies Reativas de Oxigênio/metabolismo
9.
Int J Mol Sci ; 20(11)2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31167387

RESUMO

Acute myeloid leukaemia (AML) is a heterogeneous clonal malignancy of hematopoietic progenitor cells. The Wnt pathway and its downstream targets are tightly regulated by ß-catenin. We recently discovered a new protein, FLYWCH1, which can directly bind nuclear ß-catenin. Herein, we studied the FLYWCH1/ß-catenin pathway in AML cells using qRT-PCR, Western blot, and immunofluorescence assays. In addition, the stemness activity and cell cycle were analysed by the colony-forming unit (CFU) using methylcellulose-based and Propidium iodide/flow cytometry assays. We found that FLYWCH1 mRNA and protein were differentially expressed in the AML cell lines. C-Myc, cyclin D1, and c-Jun expression decreased in the presence of higher FLYWCH1 expression, and vice versa. There appeared to be the loss of FLYWCH1 expression in dividing cells. The sub-G0 phase was prolonged and shortened in the low and high FLYWCH1 expression cell lines, respectively. The G0/G1 arrest correlated with FLYWCH1-expression, and these cell lines also formed colonies, whereas the low FLYWCH1 expression cell lines could not. Thus, FLYWCH1 functions as a negative regulator of the Wnt/ß-catenin pathway in AML.


Assuntos
Proteínas de Ligação a DNA/genética , Regulação Leucêmica da Expressão Gênica , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/metabolismo , Proteínas Wnt/metabolismo , beta Catenina/metabolismo , Ciclo Celular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/metabolismo , Imunofluorescência , Humanos , Células-Tronco Neoplásicas/metabolismo , RNA Mensageiro/genética , Via de Sinalização Wnt
11.
Cancer Res ; 78(24): 6818-6827, 2018 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-30297533

RESUMO

: Targeting PARP1 for synthetic lethality is a new strategy for breast cancers harboring germline mutations in BRCA. However, these mutations are rare, and reactivation of BRCA-mediated pathways may result in eventual resistance to PARP1 inhibitor therapy. Alternative synthetic lethality approaches targeting more common sporadic breast cancers and preinvasive ductal carcinoma in situ (DCIS) are desirable. Here we show that downregulation of XRCC1, which interacts with PARP1 and coordinates base excision repair, is an early event in human breast cancer pathogenesis. XRCC1-deficient DCIS were aggressive and associated with increased risk of local recurrence. Human invasive breast cancers deficient in XRCC1 and expressing high PARP1 levels also manifested aggressive features and poor outcome. The PARP1 inhibitor olaparib was synthetically lethal in XRCC1-deficient DCIS and invasive breast cancer cells. We conclude that targeting PARP1 is an attractive strategy for synthetic lethality and chemoprevention in XRCC1-deficient breast cancers, including preinvasive DCIS. SIGNIFICANCE: These findings show that loss of XRCC1, which is associated with more malignant DCIS, can be exploited by PARP inhibition, suggesting its application as a promising therapeutic and chemoprevention strategy in XRCC1-deficient tumor cells.


Assuntos
Neoplasias da Mama/metabolismo , Carcinoma Intraductal não Infiltrante/metabolismo , Poli(ADP-Ribose) Polimerase-1/metabolismo , Proteína 1 Complementadora Cruzada de Reparo de Raio-X/metabolismo , Apoptose , Sistemas CRISPR-Cas , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Quimioprevenção , Quebras de DNA de Cadeia Dupla , Reparo do DNA/efeitos dos fármacos , Feminino , Mutação em Linhagem Germinativa , Células HeLa , Humanos , Indazóis/farmacologia , Invasividade Neoplásica , Recidiva Local de Neoplasia , Ftalazinas/farmacologia , Piperazinas/farmacologia , Piperidinas/farmacologia , Inibidores de Poli(ADP-Ribose) Polimerases/farmacologia , Esferoides Celulares , Mutações Sintéticas Letais
12.
Leuk Lymphoma ; 59(10): 2447-2453, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29431553

RESUMO

Cells from patients with acute myeloid leukemia (AML) that remain dormant and protected by stromal cells may escape effects of chemotherapy. We modeled dormancy in vitro and investigated the ability of Bcl-2 inhibitors ABT-199 and ABT-737 to overcome chemoprotection of dormant cells. CD34-enriched primary AML cells with aberrant leukemia-associated phenotypes (LAPs) were cultured on stromal cells. The chemosensitivity of dormant (PKH26high), CD34+, LAP+ cells was ascertained by 5-colour flow cytometric counting after 12 d. The PKH26high, CD34+, LAP + subset retained clonogenic capacity. The dormant fraction was completely resistant to Ara-C (p = .007). However, ABT-199 and ABT-737 were able to reduce the dormant fraction by 84% and 80%, respectively, of their effects on proliferating counterparts. In conclusion, we have elaborated a system for quantifying chemosensitivity in LAP+ dormant leukemia cells, thought to contribute to disease relapse, and shown sensitivity of dormant LAP+ cells to ABT-199 and ABT-737 in this system.


Assuntos
Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Proliferação de Células/efeitos dos fármacos , Leucemia Mieloide Aguda/tratamento farmacológico , Recidiva Local de Neoplasia/prevenção & controle , Nitrofenóis/farmacologia , Sulfonamidas/farmacologia , Animais , Antineoplásicos/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Medula Óssea/patologia , Compostos Bicíclicos Heterocíclicos com Pontes/uso terapêutico , Linhagem Celular , Técnicas de Cocultura , Progressão da Doença , Ensaios de Seleção de Medicamentos Antitumorais , Humanos , Leucemia Mieloide Aguda/sangue , Leucemia Mieloide Aguda/patologia , Leucócitos Mononucleares , Camundongos , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Nitrofenóis/uso terapêutico , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Cultura Primária de Células , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Células Estromais , Sulfonamidas/uso terapêutico , Células Tumorais Cultivadas
13.
PLoS One ; 13(1): e0190682, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29298347

RESUMO

The BH3-only apoptosis agonists BAD and NOXA target BCL-2 and MCL-1 respectively and co-operate to induce apoptosis. On this basis, therapeutic drugs targeting BCL-2 and MCL-1 might have enhanced activity if used in combination. We identified anti-leukaemic drugs sensitising to BCL-2 antagonism and drugs sensitising to MCL-1 antagonism using the technique of dynamic BH3 profiling, whereby cells were primed with drugs to discover whether this would elicit mitochondrial outer membrane permeabilisation in response to BCL-2-targeting BAD-BH3 peptide or MCL-1-targeting MS1-BH3 peptide. We found that a broad range of anti-leukaemic agents-notably MCL-1 inhibitors, DNA damaging agents and FLT3 inhibitors-sensitise leukaemia cells to BAD-BH3. We further analysed the BCL-2 inhibitors ABT-199 and JQ1, the MCL-1 inhibitors pladienolide B and torin1, the FLT3 inhibitor AC220 and the DNA double-strand break inducer etoposide to correlate priming responses with co-operative induction of apoptosis. ABT-199 in combination with pladienolide B, torin1, etoposide or AC220 strongly induced apoptosis within 4 hours, but the MCL-1 inhibitors did not co-operate with etoposide or AC220. In keeping with the long half-life of BCL-2, the BET domain inhibitor JQ1 was found to downregulate BCL-2 and to prime cells to respond to MS1-BH3 at 48, but not at 4 hours: prolonged priming with JQ1 was then shown to induce rapid cytochrome C release when pladienolide B, torin1, etoposide or AC220 were added. In conclusion, dynamic BH3 profiling is a useful mechanism-based tool for understanding and predicting co-operative lethality between drugs sensitising to BCL-2 antagonism and drugs sensitising to MCL-1 antagonism. A plethora of agents sensitised cells to BAD-BH3-mediated mitochondrial outer membrane permeabilisation in the dynamic BH3 profiling assay and this was associated with effective co-operation with the BCL-2 inhibitory compounds ABT-199 or JQ1.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Leucemia/patologia , Azepinas/farmacologia , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Linhagem Celular Tumoral , Combinação de Medicamentos , Humanos , Indóis/farmacologia , Proteína de Sequência 1 de Leucemia de Células Mieloides/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Sulfonamidas/farmacologia , Triazóis/farmacologia
14.
Oncotarget ; 9(102): 37777-37789, 2018 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-30701031

RESUMO

Acute myeloid leukaemia (AML) cells often up-regulate pro-survival members of the BCL-2 protein family, such as BCL-2 and MCL-1, to avoid apoptosis. Venetoclax (ABT-199) targets BCL-2 and has shown promising efficacy in AML but over-expression of MCL-1 can cause resistance. A co-operative approach, targeting both BCL-2 and MCL-1 may therefore prove beneficial. This study investigated the potential synergistic relationship between Venetoclax and the MCL-1 inhibitor S63845 in AML cells. We treated MV4-11 cells and primary AML samples for 4 hours with Venetoclax, S63845 or the combination. We used a short-term flow cytometric technique to assess synergy using cytochrome C release as a read out of response. The combination of Venetoclax and S63845 produced a synergistic apoptotic response in MV4-11 cells and primary samples, including the leukaemia re-populating leukaemic stem cell (LSC) population, in 92% of the samples. Known molecular biomarkers of response to BCL-2 and MCL-1 targeting agents were corroborated, and augmented, with the short-term functional assay. The assay also predicted potential biomarkers of response to the combination of BCL-2 and MCL-1 targeting agents. Primary samples with an IDH2_140 mutation were more sensitive to Venetoclax as a single agent whereas samples with a FLT3-ITD mutation were more resistant. This resistance could be reversed when combined with S63845. All FLT3-ITD and NPM1 mutated samples were sensitive to the combination of drugs. We report that co-operatively targeting BCL-2 and MCL-1 may be beneficial in AML and a short-term in vitro assay can identify patients who might best respond to this combination.

15.
Acta Obstet Gynecol Scand ; 96(5): 556-562, 2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28176325

RESUMO

INTRODUCTION: Women with polycystic ovary syndrome have a three-fold higher risk of endometrial cancer. Insulin resistance and hyperlipidemia may be pertinent factors in the pathogenesis of both conditions. The aim of this study was to investigate endometrial sterol regulatory element binding protein-1 gene expression in polycystic ovary syndrome and endometrial cancer endometrium, and to correlate endometrial sterol regulatory element binding protein-1 gene expression with serum lipid profiles. MATERIAL AND METHODS: A cross-sectional study was performed at Nottingham University Hospital, UK. A total of 102 women (polycystic ovary syndrome, endometrial cancer and controls; 34 participants in each group) were recruited. Clinical and biochemical assessments were performed before endometrial biopsies were obtained from all participants. Taqman real-time polymerase chain reaction for endometrial sterol regulatory element binding protein-1 gene and its systemic protein expression were analyzed. RESULTS: The body mass indices of women with polycystic ovary syndrome (29.28 ± 2.91 kg/m2 ) and controls (28.58 ± 2.62 kg/m2 ) were not significantly different. Women with endometrial cancer had a higher mean body mass index (32.22 ± 5.70 kg/m2 ). Sterol regulatory element binding protein-1 gene expression was significantly increased in polycystic ovary syndrome and endometrial cancer endometrium compared with controls (p < 0.0001). Sterol regulatory element binding protein-1 gene expression was positively correlated with body mass index (r = 0.017, p = 0.921) and waist-hip ratio (r = 0.023, p = 0.544) in polycystic ovary syndrome, but this was not statistically significant. Similarly, statistically insignificant positive correlations were found between endometrial sterol regulatory element binding protein-1 gene expression and body mass index in endometrial cancer (r = 0.643, p = 0.06) and waist-hip ratio (r = 0.096, p = 0.073). Sterol regulatory element binding protein-1 gene expression was significantly positively correlated with triglyceride in both polycystic ovary syndrome and endometrial cancer (p = 0.028 and p = 0.027, respectively). Quantitative serum sterol regulatory element binding protein-1 gene correlated with endometrial gene expression (p < 0.05). CONCLUSIONS: Sterol regulatory element binding protein-1 gene expression is significantly increased in the endometrium of women with polycystic ovary syndrome and women with endometrial cancer compared with controls and positively correlates with serum triglyceride in both polycystic ovary syndrome and endometrial cancer.


Assuntos
Neoplasias do Endométrio/genética , Síndrome do Ovário Policístico/genética , Proteína de Ligação a Elemento Regulador de Esterol 1/genética , Adulto , Estudos de Casos e Controles , Estudos Transversais , Neoplasias do Endométrio/sangue , Neoplasias do Endométrio/metabolismo , Endométrio/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Lipídeos/sangue , Pessoa de Meia-Idade , Síndrome do Ovário Policístico/sangue , Síndrome do Ovário Policístico/metabolismo , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo
16.
Oncotarget ; 8(67): 111405-111418, 2017 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-29340063

RESUMO

Dormant leukaemia initiating cells in the bone marrow niche are a crucial therapeutic target for total eradication of acute myeloid leukaemia. To study this cellular subset we created and validated an in vitro model employing the cell line TF-1a, treated with Transforming Growth Factor ß1 (TGFß1) and a mammalian target of rapamycin inhibitor. The treated cells showed decreases in total RNA, Ki-67 and CD71, increased aldehyde dehydrogenase activity, forkhead box 03A (FOX03A) nuclear translocation and growth inhibition, with no evidence of apoptosis or differentiation. Using human genome gene expression profiling we identified a signature enriched for genes involved in adhesion, stemness/inhibition of differentiation and tumour suppression as well as canonical cell cycle regulation. The most upregulated gene was the osteopontin-coding gene SPP1. Dormant cells also demonstrated significantly upregulated beta 3 integrin (ITGB3) and CD44, as well as increased adhesion to their ligands vitronectin and hyaluronic acid as well as to bone marrow stromal cells. Immunocytochemistry of bone marrow biopsies of AML patients confirmed the positive expression of osteopontin in blasts near the para-trabecular bone marrow, whereas osteopontin was rarely detected in mononuclear cell isolates. Unsupervised hierarchical clustering of the dormancy gene signature in primary acute myeloid leukaemia samples from the Cancer Genome Atlas identified a cluster enriched for dormancy genes associated with poor overall survival.

17.
Oncotarget ; 8(10): 16220-16232, 2017 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-27092880

RESUMO

Direct co-operation between sensitiser molecules BAD and NOXA in mediating apoptosis suggests that therapeutic agents which sensitise to BAD may complement agents which sensitise to NOXA. Dynamic BH3 profiling is a novel methodology that we have applied to the measurement of complementarity between sensitiser BH3 peptide mimetics and therapeutic agents. Using dynamic BH3 profiling, we show that the agent TG02, which downregulates MCL-1, sensitises to the BCL-2-inhibitory BAD-BH3 peptide, whereas the BCL-2 antagonist ABT-199 sensitises to MCL-1 inhibitory NOXA-BH3 peptide in acute myeloid leukaemia (AML) cells. At the concentrations used, the peptides did not trigger mitochondrial outer membrane permeabilisation in their own right, but primed cells to release Cytochrome C in the presence of an appropriate trigger of a complementary pathway. In KG-1a cells TG02 and ABT-199 synergised to induce apoptosis. In heterogeneous AML patient samples we noted a range of sensitivities to the two agents. Although some individual samples markedly favoured one agent or the other, in the group as a whole the combination of TG02 + ABT-199 was significantly more cytotoxic than either agent individually. We conclude that dynamic NOXA and BAD BH3 profiling is a sensitive methodology for investigating molecular pathways of drug action and complementary mechanisms of chemoresponsiveness.


Assuntos
Apoptose/efeitos dos fármacos , Compostos Bicíclicos Heterocíclicos com Pontes/farmacologia , Compostos Heterocíclicos de 4 ou mais Anéis/farmacologia , Leucemia Mieloide/tratamento farmacológico , Sulfonamidas/farmacologia , Doença Aguda , Antineoplásicos/farmacologia , Apoptose/genética , Materiais Biomiméticos/farmacologia , Western Blotting , Linhagem Celular Tumoral , Ciclina D1/antagonistas & inibidores , Ciclina D1/genética , Ciclina D1/metabolismo , Citocromos c/metabolismo , Sinergismo Farmacológico , Regulação Leucêmica da Expressão Gênica/efeitos dos fármacos , Humanos , Leucemia Mieloide/genética , Leucemia Mieloide/metabolismo , Proteína de Sequência 1 de Leucemia de Células Mieloides/genética , Proteína de Sequência 1 de Leucemia de Células Mieloides/metabolismo , Fragmentos de Peptídeos/farmacologia , Proteínas Proto-Oncogênicas/farmacologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa
18.
Mol Cell Endocrinol ; 424: 94-101, 2016 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-26802879

RESUMO

BACKGROUND: Endometrial cancer (EC) is the most common gynaecological cancer amongst women in the UK. Although previous studies have found that women with polycystic ovary syndrome (PCOS) have at least a three-fold increase in endometrial cancer (EC) risk compared to women without PCOS, the precise molecular mechanisms which link between PCOS and EC remain unclear. It has been suggested that insulin resistance may contribute to the increased risk of EC in PCOS. The specific expression of genes related to the insulin-signalling pathway including the IGF system in the endometrium of women with PCOS has however never been measured and compared to that in women with EC without PCOS and control women without EC or PCOS. . OBJECTIVES: To test the hypothesis that insulin signalling plays a key role in the development of EC in women with PCOS by measuring and comparing the expression of three key genes involved in the insulin signalling pathway (IGF1, PTEN and IGFBP1) in endometrial tissue obtained from three groups of women; PCOS without EC, women with EC without PCOS and non-PCOS women without EC (controls). We also aimed to determine the correlation between the gene expressions to various clinical variables among participants. METHODS: This was a cross-sectional study of 102 women in 3 groups (PCOS, EC and controls) at a University teaching hospital in the United Kingdom. Clinical assessment (blood pressure, body mass index (BMI) and waist-hip-circumference ratio), venepuntures (fasting blood sugar, insulin, lipid profile, hormones) and endometrial tissue biopsies were taken in all participants. Endometrial tissue RNA extraction was performed before real time polymerase-chain-reaction for the genes of interest (IGF1, IGFBP1 and PTEN) was carried out. To compare the baseline characteristics of the study population, One-Way-ANOVA test or the Independent t-test was used. For variables that were not normally distributed, the Spearman correlation test was used to calculate the r value. A "p" value of <0.05 was considered statistically significant. RESULTS: IGF1, IGFBP1 and PTEN gene expression were significantly up-regulated in the endometrium of PCOS and EC women compared to controls. However there was no significant difference in the expression of these genes in PCOS compared to EC endometrium. The BMI of women with PCOS and controls, were not significantly different (29.28 (± 2.91) vs 28.58 (± 2.62) kg/m(2)) respectively, women with EC however had a higher mean BMI (32.22 (± 5.70) kg/m(2)). PCOS women were younger (31.8 (± 5.97) years) than women with EC (63.44 (± 10.07) years) and controls (43.68 (± 13.12) years). The changes in gene expression were independent of BMI, waist hip ratio, estradiol and androgen levels. Protein validation test in the serum samples in the three groups were consistent with the gene findings. CONCLUSION: Women with PCOS and EC have an increased endometrial expression of genes (IGF1, IGFBP1 and PTEN) involved in the insulin signalling pathway compared with control women. This may explain the increased risk of EC in PCOS women. This study provides a strong basis for clinical trials aiming to prevent EC in women with PCOS by investigating drugs targeting the insulin signalling pathway. This panel of genes may also serve as clinically useful early biomarkers which predict which women with PCOS will go on to develop EC.


Assuntos
Neoplasias do Endométrio/genética , Fator de Crescimento Insulin-Like I/genética , Peptídeos e Proteínas de Sinalização Intracelular/genética , PTEN Fosfo-Hidrolase/genética , Síndrome do Ovário Policístico/genética , Regulação para Cima , Proteínas Adaptadoras de Transdução de Sinal , Adulto , Idoso , Índice de Massa Corporal , Estudos Transversais , Feminino , Predisposição Genética para Doença , Humanos , Insulina/metabolismo , Pessoa de Meia-Idade , Chaperonas Moleculares , Transdução de Sinais
19.
Mol Oncol ; 9(1): 204-17, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25205036

RESUMO

BRCA1, a key factor in homologous recombination (HR) repair may also regulate base excision repair (BER). Targeting BRCA1-BER deficient cells by blockade of ATM and DNA-PKcs could be a promising strategy in breast cancer. We investigated BRCA1, XRCC1 and pol ß protein expression in two cohorts (n = 1602 sporadic and n = 50 germ-line BRCA1 mutated) and mRNA expression in two cohorts (n = 1952 and n = 249). Artificial neural network analysis for BRCA1-DNA repair interacting genes was conducted in 249 tumours. Pre-clinically, BRCA1 proficient and deficient cells were DNA repair expression profiled and evaluated for synthetic lethality using ATM and DNA-PKcs inhibitors either alone or in combination with cisplatin. In human tumours, BRCA1 negativity was strongly associated with low XRCC1, and low pol ß at mRNA and protein levels (p < 0.0001). In patients with BRCA1 negative tumours, low XRCC1 or low pol ß expression was significantly associated with poor survival in univariate and multivariate analysis compared to high XRCC1 or high pol ß expressing BRCA1 negative tumours (ps < 0.05). Pre-clinically, BRCA1 negative cancer cells exhibit low mRNA and low protein expression of XRCC1 and pol ß. BRCA1-BER deficient cells were sensitive to ATM and DNA-PKcs inhibitor treatment either alone or in combination with cisplatin and synthetic lethality was evidenced by DNA double strand breaks accumulation, cell cycle arrest and apoptosis. We conclude that XRCC1 and pol ß expression status in BRCA1 negative tumours may have prognostic significance. BRCA1-BER deficient cells could be targeted by ATM or DNA-PKcs inhibitors for personalized therapy.


Assuntos
Proteínas Mutadas de Ataxia Telangiectasia/antagonistas & inibidores , Proteína BRCA1/metabolismo , Neoplasias da Mama/tratamento farmacológico , Cisplatino/farmacologia , Reparo do DNA , Proteína Quinase Ativada por DNA/antagonistas & inibidores , Proteínas Nucleares/antagonistas & inibidores , Medicina de Precisão , Inibidores de Proteínas Quinases/farmacologia , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteínas Mutadas de Ataxia Telangiectasia/metabolismo , Proteína BRCA1/genética , Neoplasias da Mama/enzimologia , Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Linhagem Celular Tumoral , Estudos de Coortes , Quebras de DNA de Cadeia Dupla , Proteína Quinase Ativada por DNA/genética , Proteína Quinase Ativada por DNA/metabolismo , Intervalo Livre de Doença , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Taxa de Sobrevida
20.
Gynecol Endocrinol ; 31(4): 286-90, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25495168

RESUMO

The aim of this proof-of-concept study was to determine the effects of three-month Metformin therapy on the expression of tumor-regulatory genes (p53, cyclin D2 and BCL-2) in the endometrium of women with polycystic ovary syndrome (PCOS). A total of 40 women, aged between 21 and 45 years with PCOS (Rotterdam criteria) were recruited. The participants were assessed at pre- and 3-month-post-Metformin therapy for the menstrual regularities, weight reduction, Ferriman Galway scores, fasting blood glucose (FBG), total cholesterol, LDL, HDL and p53, BCL-2 and cyclin D2 gene expression. Five participants conceived spontaneously after the initial recruitment. Majority (68%) resumed regular menstrual cycles after Metformin. There were significant reduction in BMI (p = 0.001), weight (p = 0.001) and Ferriman Galway scores (p = 0.001). A significant improvement was seen in mean FBG (p = 0.002), total cholesterol (p = 0.001), LDL (p = 0.003) and HDL cholesterol levels (p = 0.015). Tumor suppressor gene (p53) was significantly up-regulated after Metformin (10 out of 14 women), with p value 0.016. BCL-2 and cyclin D2 (oncogenes) were slightly up-regulated without significant difference (p = 0.119 and 0.155, respectively). In conclusion, Metformin therapy improved clinical and metabolic parameters in women with PCOS and up-regulated p53 tumor suppressor gene significantly. Further studies are however required to independently validate our findings.


Assuntos
Endométrio/efeitos dos fármacos , Hipoglicemiantes/uso terapêutico , Metformina/uso terapêutico , Sobrepeso/prevenção & controle , Síndrome do Ovário Policístico/tratamento farmacológico , Proteína Supressora de Tumor p53/agonistas , Regulação para Cima/efeitos dos fármacos , Adulto , Biópsia , Índice de Massa Corporal , Estudos de Coortes , Ciclina D2/agonistas , Ciclina D2/genética , Ciclina D2/metabolismo , Neoplasias do Endométrio/complicações , Neoplasias do Endométrio/epidemiologia , Neoplasias do Endométrio/prevenção & controle , Endométrio/metabolismo , Endométrio/patologia , Feminino , Fase Folicular/metabolismo , Humanos , Hipoglicemiantes/efeitos adversos , Malásia/epidemiologia , Metformina/efeitos adversos , Sobrepeso/complicações , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/metabolismo , Síndrome do Ovário Policístico/patologia , Estudos Prospectivos , Proteínas Proto-Oncogênicas c-bcl-2/agonistas , Proteínas Proto-Oncogênicas c-bcl-2/genética , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Risco , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Redução de Peso/efeitos dos fármacos , Adulto Jovem
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