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1.
Proteomics ; 24(11): e2300055, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38644352

RESUMO

Endometrial cancer, the most common gynaecological cancer worldwide, is closely linked to obesity and metabolic diseases, particularly in younger women. New circulating biomarkers have the potential to improve diagnosis and treatment selections, which could significantly improve outcomes. Our approach focuses on extracellular vesicle (EV) biomarker discovery by directly profiling the proteome of EVs enriched from frozen biobanked endometrial tumours. We analysed nine tissue samples to compare three clinical subgroups-low BMI (Body Mass Index) Endometrioid, high BMI Endometrioid, and Serous (any BMI)-identifying proteins related to histological subtype, BMI, and shared secreted proteins. Using collagenase digestion and size exclusion chromatography, we successfully enriched generous quantities of EVs (range 204.8-1291.0 µg protein: 1.38 × 1011-1.10 × 1012 particles), characterised by their size (∼150 nm), expression of EV markers (CD63/81), and proposed endometrial cancer markers (L1CAM, ANXA2). Mass spectrometry-based proteomic profiling identified 2075 proteins present in at least one of the 18 samples. Compared to cell lysates, EVs were successfully depleted for mitochondrial and blood proteins and enriched for common EV markers and large secreted proteins. Further analysis highlighted significant differences in EV protein profiles between the high BMI subgroup and others, underlining the impact of comorbidities on the EV secretome. Interestingly, proteins differentially abundant in tissue subgroups were largely not also differential in matched EVs. This research identified secreted proteins known to be involved in endometrial cancer pathophysiology and proposed novel diagnostic biomarkers (EIF6, MUC16, PROM1, SLC26A2).


Assuntos
Biomarcadores Tumorais , Neoplasias do Endométrio , Vesículas Extracelulares , Obesidade , Proteoma , Humanos , Feminino , Neoplasias do Endométrio/metabolismo , Neoplasias do Endométrio/patologia , Vesículas Extracelulares/metabolismo , Proteoma/metabolismo , Proteoma/análise , Obesidade/metabolismo , Obesidade/patologia , Biomarcadores Tumorais/metabolismo , Proteômica/métodos , Índice de Massa Corporal , Pessoa de Meia-Idade
2.
J Liposome Res ; 34(3): 489-506, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38269490

RESUMO

Breast cancer stem cells (BCSCs) play a key role in therapeutic resistance in breast cancer treatments and disease recurrence. This study aimed to develop a combination therapy loaded with pH-sensitive liposomes to kill both BCSCs and the okbulk cancer cells using trastuzumab-sensitive and resistant human epidermal growth factor receptor 2 positive (HER2+) breast cancer cell models. The anti-BCSCs effect and cytotoxicity of all-trans retinoic acid, salinomycin, and bufalin alone or in combination with doxorubicin were compared in HER2+ cell line BT-474 and a validated trastuzumab-resistant cell line, BT-474R. The most potent anti-BCSC agent was selected and loaded into a pH-sensitive liposome system. The effects of the liposomal combination on BCSCs and bulk cancer cells were assessed. Compared with BT-474, the aldehyde dehydrogenase positive BCSC population was elevated in BT-474R (3.9 vs. 23.1%). Bufalin was the most potent agent and suppressed tumorigenesis of BCSCs by ∼50%, and showed strong synergism with doxorubicin in both BT-474 and BT-474R cell lines. The liposomal combination of bufalin and doxorubicin significantly reduced the BCSC population size by 85%, and inhibited both tumorigenesis and self-renewal, although it had little effect on the migration and invasiveness. The cytotoxicity against the bulk cancer cells was also enhanced by the liposomal combination than either formulation alone in both cell lines (p < 0.001). The liposomal bufalin and doxorubicin combination therapy may effectively target both BCSCs and bulk cancer cells for a better outcome in trastuzumab-resistant HER2+ breast cancer.


Assuntos
Neoplasias da Mama , Bufanolídeos , Doxorrubicina , Resistencia a Medicamentos Antineoplásicos , Lipossomos , Células-Tronco Neoplásicas , Trastuzumab , Humanos , Doxorrubicina/farmacologia , Doxorrubicina/administração & dosagem , Bufanolídeos/farmacologia , Bufanolídeos/administração & dosagem , Bufanolídeos/química , Células-Tronco Neoplásicas/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Neoplasias da Mama/tratamento farmacológico , Neoplasias da Mama/patologia , Lipossomos/química , Feminino , Trastuzumab/farmacologia , Trastuzumab/administração & dosagem , Linhagem Celular Tumoral , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/administração & dosagem , Proliferação de Células/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Receptor ErbB-2/metabolismo , Sobrevivência Celular/efeitos dos fármacos
3.
Pharm Dev Technol ; 28(3-4): 288-298, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36912800

RESUMO

The anti-HER2 antibody trastuzumab has been proven to be an effective targeting ligand for drug delivery. This study investigates the structural integrity of trastuzumab under different stress factors in formulation development and its long-term stability. A validated size exclusion high performance liquid chromatographic (SEC-HPLC) method was first developed. The stability of trastuzumab (0.21-21 mg/ml) under stress conditions (mechanical, freeze-and-thaw, pH and temperature) and long-term storage in the presence of formulation excipients were monitored for up to 12 months, using both the SEC-HPLC method and sodium-dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The anti-proliferation activity of the reconstituted antibody stored at 4 °C against HER2+ BT-474 breast cells was also monitored over 12 months. The developed SEC-HPLC method was sensitive and accurate. Solutions of trastuzumab were resistant to mechanical stress and repeated freeze-and-thaw; but were unstable under acidic (pH 2.0 and 4.0) and alkaline (pH 10.0 and 12.0) environments. The samples degraded over 5 days at 60 °C, and within 24 h at 75 °C. Low temperature (-80 °C or 4 °C) and low concentration (0.21 mg/ml) favoured the long-term stability. The anti-proliferation activity was conserved at 4 °C for at least 12 months. This study provided valuable stability information in developing trastuzumab involved nano-formulation as well as in clinical settings.


Assuntos
Nanomedicina , Trastuzumab/farmacologia , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Eletroforese em Gel de Poliacrilamida
4.
Diabetologia ; 61(7): 1603-1613, 2018 07.
Artigo em Inglês | MEDLINE | ID: mdl-29721634

RESUMO

AIMS/HYPOTHESIS: The A (minor) allele of CREBRF rs373863828 has been associated with increased BMI and reduced risk of type 2 diabetes in the Samoan populations of Samoa and American Samoa. Our aim was to test rs373863828 for associations with BMI and the odds of type 2 diabetes, gout and chronic kidney disease (CKD) in Maori and Pacific (Polynesian) people living in Aotearoa/New Zealand. METHODS: Linear and logistic regression models were used to analyse the association of the A allele of CREBRF rs373863828 with BMI, log-transformed BMI, waist circumference, type 2 diabetes, gout and CKD in 2286 adults. The primary analyses were adjusted for age, sex, the first four genome-wide principal components and (where appropriate) BMI, waist circumference and type 2 diabetes. The primary analysis was conducted in ancestrally defined groups and association effects were combined using meta-analysis. RESULTS: For the A allele of rs373863828, the effect size was 0.038 (95% CI 0.022, 0.055, p = 4.8 × 10-6) for log-transformed BMI, with OR 0.59 (95% CI 0.47, 0.73, p = 1.9 × 10-6) for type 2 diabetes. There was no evidence for an association of genotype with variance in BMI (p = 0.13), and nor was there evidence for associations with serum urate (ß = 0.012 mmol/l, pcorrected = 0.10), gout (OR 1.00, p = 0.98) or CKD (OR 0.91, p = 0.59). CONCLUSIONS/INTERPRETATION: Our results in New Zealand Polynesian adults replicate, with very similar effect sizes, the association of the A allele of rs373863828 with higher BMI but lower odds of type 2 diabetes among Samoan adults living in Samoa and American Samoa.


Assuntos
Índice de Massa Corporal , Diabetes Mellitus Tipo 2/prevenção & controle , Havaiano Nativo ou Outro Ilhéu do Pacífico/genética , Obesidade/genética , Polimorfismo de Nucleotídeo Único , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/etnologia , Diabetes Mellitus Tipo 2/genética , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Obesidade/diagnóstico , Obesidade/etnologia , Fenótipo , Polinésia/etnologia , Fatores de Proteção , Fatores de Risco
5.
Pediatr Exerc Sci ; 30(1): 69-80, 2018 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-28661716

RESUMO

PURPOSE: The decline of physical activity in children is considered an important determinant to explain the rising rates of obesity. However, this risk may be augmented in children who are genetically susceptible to increased weight gain. We hypothesized that a sedentary lifestyle and moderate activity will interact with genetic loci, resulting in differential effects in relation to obesity risk. METHODS: We recruited 643 European children born to participants in the New Zealand-based Screening for Pregnancy Endpoints (SCOPE) study. Seventy gene variants were evaluated by the Sequenom assay. Interaction analyses were performed between the genetic variants and the activity type derived from actigraphy, in relation to percentage body fat. RESULTS: We found a statistically significant association between increased proportions of sedentary activity with increased percentage body fat scores (P = .012). The OLFM4-9568856 (P = .01) and GNPDA2-rs10938397 (P = .044) gene variants showed genotype differences with proportions of sedentary activity. Similarly, the OLFM4-9568856 (P = .021), CLOCK-rs4864548 (P = .029), and LEPR-1045895 (P = .047) showed genotype differences with proportions of moderate activity. We found evidence for unadjusted gene-by-activity interactions of SPACA3/SPRASA-rs16967845, PFKP-rs6602024, and SH2B1-rs7498665 on percentage body fat scores. CONCLUSIONS: These findings indicate a differential effect of physical activity in relation to obesity risk, suggesting that children genetically predisposed to increased weight gain may benefit from higher levels of moderate activity.


Assuntos
Exercício Físico , Predisposição Genética para Doença , Genótipo , Obesidade Infantil/genética , Comportamento Sedentário , Actigrafia , Adiposidade , Criança , Feminino , Humanos , Masculino , Nova Zelândia , Polimorfismo de Nucleotídeo Único , População Branca
6.
Int J Cancer ; 139(5): 1157-70, 2016 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-27072400

RESUMO

Chemotherapy with taxanes such as paclitaxel (PTX) is a key component of triple negative breast cancer (TNBC) treatment. PTX is used in combination with other drugs in both the adjuvant setting and in advanced breast cancer. Because a proportion of patients respond poorly to PTX or relapse after its use, a greater understanding of the mechanisms conferring resistance to PTX is required. One protein shown to be involved in drug resistance is Y-box binding protein 1 (YB-1). High levels of YB-1 have previously been associated with resistance to PTX in TNBCs. In this study, we aimed to determine mechanisms by which YB-1 confers PTX resistance. We generated isogenic TNBC cell lines that differed by YB-1 levels and treated these with PTX. Using microarray analysis, we identified EGR1 as a potential target of YB-1. We found that low EGR1 mRNA levels are associated with poor breast cancer patient prognosis, and that EGR1 and YBX1 mRNA expression was inversely correlated in a TNBC line and in a proportion of TNBC tumours. Reducing the levels of EGR1 caused TNBC cells to become more resistant to PTX. Given that PTX targets cycling cells, we propose a model whereby high YB-1 levels in some TNBC cells can lead to reduced levels of EGR1, which in turn promotes slow cell cycling and resistance to PTX. Therefore YB-1 and EGR1 levels are biologically linked and may provide a biomarker for TNBC response to PTX.


Assuntos
Antineoplásicos Fitogênicos/farmacologia , Resistencia a Medicamentos Antineoplásicos , Proteína 1 de Resposta de Crescimento Precoce/metabolismo , Paclitaxel/farmacologia , Neoplasias de Mama Triplo Negativas/metabolismo , Proteína 1 de Ligação a Y-Box/metabolismo , Linhagem Celular Tumoral , Resistencia a Medicamentos Antineoplásicos/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Feminino , Expressão Gênica , Perfilação da Expressão Gênica , Humanos , Estimativa de Kaplan-Meier , Prognóstico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Neoplasias de Mama Triplo Negativas/tratamento farmacológico , Neoplasias de Mama Triplo Negativas/genética , Neoplasias de Mama Triplo Negativas/mortalidade , Proteína 1 de Ligação a Y-Box/genética
7.
Mol Hum Reprod ; 22(4): 261-71, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26792869

RESUMO

STUDY HYPOTHESIS: Maternal ageing and ovarian stimulation result in the accumulation of mitochondrial DNA (mtDNA) deletions and heteroplasmy in individual oocytes from a novel bovine model for human assisted reproductive technology (ART). STUDY FINDING: The levels of mtDNA deletions detected in oocytes increased with ovarian ageing. Low levels of mtDNA heteroplasmy were apparent across oocytes and no relationship was identified with respect to ovarian ageing or ovarian stimulation. WHAT IS KNOWN ALREADY: Oocyte quality decreases with ovarian ageing and it is postulated that the mtDNA may have a role in this decline. The impact of ovarian stimulation on oocyte quality is poorly understood. Human studies investigating these effects are often limited by the use of low quality oocytes and embryos, variation in age and ovarian stimulation regimens within the patients studied, as well as genetic and environmental variability. Further, no study has investigated mtDNA heteroplasmy in individual oocytes using next-generation sequencing (NGS), and little is known about whether the oocyte accumulates heteroplasmic mtDNA mutations following ageing or ovarian stimulation. STUDY DESIGN, SAMPLES/MATERIALS, METHODS: A novel bovine model for the effect of stimulation and age in human ART was undertaken using cows generated by somatic cell nuclear transfer (SCNT) from one founder, to produce a homogeneous population with reduced genetic and environmental variability. Oocytes and somatic tissues were collected from young (3 years of age; n = 4 females) and old (10 years of age; n = 5 females) cow clones following multiple natural ovarian cycles, as well as oocytes following multiple mild (FSH only) and standard (based on human a long GnRH agonist protocol) ovarian stimulation cycles. In addition, oocytes were recovered in a natural cycle from naturally conceived cows aged 4-13.5 years (n = 10) to provide a heterogeneous cohort for mtDNA deletion studies. The presence or absence of mtDNA deletions were investigated using long-range PCR in individual oocytes (n = 62). To determine the detection threshold for mtDNA heteroplasmy levels in individual oocytes, a novel NGS methodology was validated; artificial mixtures of the Bos taurus and Bos indicus mitochondrial genome were generated at 1, 2, 5, 15 and 50% ratios to experimentally mimic different levels of heteroplasmy. This NGS methodology was then employed to determine mtDNA heteroplasmy levels in single oocytes (n = 24). Oocyte mtDNA deletion and heteroplasmy data were analysed by binary logistic regression with respect to the effects of ovarian ageing and ovarian stimulation regimens. MAIN RESULTS AND THE ROLE OF CHANCE: Ovarian ageing, but not ovarian stimulation, increased the number of oocytes exhibiting mtDNA deletions (P = 0.04). A minimum mtDNA heteroplasmy level of 2% was validated as a sensitive (97-100%) threshold for variant detection in individual oocytes using NGS. Few mtDNA heteroplasmies were detected across the individual oocytes, with only 15 oocyte-specific variants confined to two of the 24 oocytes studied. There was no relationship (P > 0.05) evident between ovarian ageing or ovarian stimulation and the presence of mtDNA heteroplasmies. LIMITATIONS, REASON FOR CAUTION: The low number of oocytes collected from the natural ovarian cycles limited the analysis. Fertilization and developmental potential of the oocytes was not assessed as the oocytes were destroyed for mtDNA deletion and heteroplasmy analysis. WIDER IMPLICATIONS OF THE FINDINGS: If the findings of this model apply to the human, this study suggests that the incidence of mtDNA deletions increases with age, but not with degree of ovarian stimulation, while the frequency of mtDNA heteroplasmies may be low regardless of ovarian ageing or level of ovarian stimulation. STUDY FUNDING AND COMPETING INTERESTS: Funding was provided by Fertility Associates, the Nurture Foundation for Reproductive Research, the Fertility Society of Australia, and the Auckland Medical Research Foundation. J.C.P. is a shareholder of Fertility Associates and M.P.G. received a fellowship from Fertility Associates. The other authors of this manuscript declare no conflict of interest that could be perceived as prejudicing the impartiality of the reported research.


Assuntos
Envelhecimento/genética , DNA Mitocondrial/genética , Ciclo Menstrual/genética , Mitocôndrias/genética , Oócitos/metabolismo , Adulto , Envelhecimento/patologia , Animais , Bovinos , Feminino , Hormônio Foliculoestimulante/farmacologia , Hormônio Liberador de Gonadotropina/farmacologia , Humanos , Modelos Logísticos , Ciclo Menstrual/efeitos dos fármacos , Pessoa de Meia-Idade , Mitocôndrias/patologia , Modelos Biológicos , Técnicas de Transferência Nuclear , Oócitos/efeitos dos fármacos , Oócitos/patologia , Indução da Ovulação
8.
Hum Reprod ; 31(8): 1653-61, 2016 08.
Artigo em Inglês | MEDLINE | ID: mdl-27270971

RESUMO

The ability to screen embryos for aneuploidy or inherited disorders in a minimally invasive manner may represent a major advancement for the future of embryo viability assessment. Recent studies have demonstrated that both blastocoele fluid and embryo culture medium contain genetic material, which can be isolated and subjected to downstream genetic analysis. The blastocoele fluid may represent an alternative source of nuclear DNA for aneuploidy testing, although the degree to which the isolated genetic material is solely representative of the developing embryo is currently unclear. In addition to nuclear DNA, mitochondrial DNA (mtDNA) can be detected in the embryo culture medium. Currently, the origin of this nuclear and mtDNA has not been fully evaluated and there are several potential sources of contamination that may contribute to the genetic material detected in the culture medium. There is however evidence that the mtDNA content of the culture medium is related to embryo fragmentation levels and its presence is predictive of blastulation, indicating that embryo development may influence the levels of genetic material detected. If the levels of genetic material are strongly related to aspects of embryo quality, then this may be a novel biomarker of embryo viability. If the genetic material does have an embryo origin, the mechanisms by which DNA may be released into the blastocoele fluid and embryo culture medium are unknown, although apoptosis may play a role. While the presence of this genetic material is an exciting discovery, the DNA in the blastocoele fluid and embryo culture medium appears to be of low yield and integrity, which makes it challenging to study. Further research aimed at assessing the methodologies used for both isolating and analysing this genetic material, as well as tracing its origin, are needed in order to evaluate its potential for clinical use. Should such methodologies prove to be routinely successful and the DNA recovered demonstrated to be embryonic in origin, then they may be used in a minimally invasive and less technical methodology for genetic analysis and embryo viability assessment than those currently available.


Assuntos
Meios de Cultura/química , DNA/análise , Técnicas de Cultura Embrionária , Testes Genéticos/métodos , Diagnóstico Pré-Implantação/métodos , Aneuploidia , Blastocisto/metabolismo , DNA Mitocondrial/análise , Humanos
9.
J Cardiovasc Electrophysiol ; 26(12): 1346-51, 2015 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-26332198

RESUMO

INTRODUCTION: The accurate prediction of the risk of sudden cardiac death (SCD) in hypertrophic cardiomyopathy (HCM) remains elusive. Corrected QT interval (QTc) duration is a known risk factor in various cardiac conditions. Single nucleotide polymorphisms (SNPs) have been linked to QTc length, and to SCD. Here we investigated the role of 21 candidate SNPs in QTc duration and SCD events in patients with HCM. METHODS AND RESULTS: This HCM registry-based study included patients with an ECG, medical history, first SCD event data, and DNA available. Each individual SNP was assessed using logistic regression for associations with 2 outcomes: a prolonged QTc ( ≥440 milliseconds), and first SCD event (SCD, resuscitated cardiac arrest, and appropriate implantable cardioverter defibrillator (ICD) shock for ventricular fibrillation/ventricular tachycardia (VF/VT). In 272 HCM patients, there were 31 SCD events (8 SCD, 9 resuscitated cardiac arrest, 14 ICD shocks for VF/VT; 11%). A QTc ≥ 500 milliseconds was associated with SCD events on multivariate analysis (odds ratio [OR] = 4.0, 95% confidence interval [CI], 1.19-12.02, P = 0.016). In 228 Caucasian patients, 2 SNPs in the NOS1AP gene (rs10494366 and rs12143842) were associated with a prolonged QTc after correction for multiple testing. This remained significant after adjustment for current age, sex, and ≥1 SCD risk factor (OR 1.59 per copy of the minor allele, 95% CI 1.08-2.39, P = 0.022, and OR 1.63, 95% CI 1.09-2.49, P = 0.020, respectively). No SNPs were directly associated with SCD events. CONCLUSION: SNPs in the NOS1AP gene influence QTc interval duration but we have not demonstrated a direct association with the risk of SCD.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Cardiomiopatia Hipertrófica/genética , Cardiomiopatia Hipertrófica/fisiopatologia , Parada Cardíaca/etiologia , Parada Cardíaca/genética , Síndrome do QT Longo/genética , Síndrome do QT Longo/fisiopatologia , Idoso , Cardiomiopatia Hipertrófica/epidemiologia , Estudos de Coortes , DNA/genética , Morte Súbita Cardíaca , Desfibriladores Implantáveis , Eletrocardiografia , Feminino , Parada Cardíaca/epidemiologia , Humanos , Síndrome do QT Longo/epidemiologia , Masculino , Pessoa de Meia-Idade , Nova Zelândia/epidemiologia , Polimorfismo de Nucleotídeo Único , Risco , Resultado do Tratamento
10.
Hum Reprod ; 30(8): 1850-60, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26040474

RESUMO

STUDY QUESTION: Are there associations between early time-lapse parameters, expression of candidate embryo viability genes in cumulus cells and embryo quality on Day 5? SUMMARY ANSWER: Early time-lapse parameters correlate to the expression levels of candidate embryo viability genes in cumulus cells but a combined analysis including both time-lapse and candidate gene expression did not identify significant predictors of embryo quality on Day 5. WHAT IS KNOWN ALREADY: Recent evidence suggests that early time-lapse parameters are predictive of blastocyst development. Similarly, a number of candidate genes in cumulus cells have been identified as potential markers of embryo viability. Relationships between time-lapse parameters and candidate gene expression in cumulus cells have not been investigated, and a combined analysis of these markers has not been attempted in relation to embryo quality. STUDY DESIGN, SIZE, DURATION: A total of 78 embryos obtained by ICSI from 22 patients were studied by time-lapse and measurement of cumulus cell gene expression of known markers of embryo viability. Time-lapse and cumulus cell gene expression data were assessed in relation to embryo quality on Day 5. PARTICIPANTS/MATERIALS, SETTING, METHODS: All women, aged 32-40 years, underwent ICSI treatment for male infertility. Embryos with annotatable time to pronuclear breakdown (tPNB), division to two cells (t2C), three cells (t3C), four cells (t4C) and five cells (t5C) were included in the study. Expression levels of 27 candidate genes for embryo viability were measured in 78 associated cumulus cell masses using quantitative real-time PCR. MAIN RESULTS AND THE ROLE OF CHANCE: Cumulus cell expression of 11 candidate genes involved in energy metabolism (ATPase, H+ transporting, lysosomal 70 kDa, V1 subunit A (ATP6V1A), NADH dehydrogenase (ubiquinone) 1 alpha subcomplex, 1, 7.5 kDa (NDUFA1), lactate dehydrogenase A (LDHA), phosphofructokinase platelet (PFKP) and solute carrier family 2 member 4 (SLC2A4), mitochondrial biogenesis (DNA directed RNA polymerase, mitochondrial (POLRMT) and transcription factor A, mitochondrial (TFAM), signalling (prostaglandin-endoperoxide synthase 2), steroidogenesis (cytochrome P450, family 11, subfamily A, polypeptide 1 (CYP11A1) and cell stress (heat shock 70 kDa protein 5 (HSPA5) and peroxiredoxin 3 (PRDX3)) correlated to time-lapse parameters of the developing embryo, largely for t3C onwards (all P < 0.05). Expression of ATP synthase, H+ transporting, mitochondrial Fo complex, subunit E (ATP51), HSPA5, PFKP, PRDX3 and versican (VCAN) and the parameter t4C were also related to embryo quality on Day 5 (all P < 0.05). Ordinal logistic regression, where gene expression and time-lapse parameters were combined, did not identify any significant predictors of embryo quality on Day 5. LIMITATIONS AND REASON FOR CAUTION: Data are from a preliminary study, limited by a small sample size and using more than one ovarian stimulation protocol. A possible limitation is that each follicle was treated as an independent observation, although a considerable fraction of embryos were from the same patient. WIDER IMPLICATIONS OF THE FINDINGS: Results presented in this study suggest that some of the variation of time-lapse parameters may be related to cumulus cell gene expression and thus the ovarian microenvironment in which the oocyte developed. Although the current study did not identify significant predictors of embryo quality on Day 5, investigation in a larger cohort may determine whether cumulus cell gene expression and time-lapse parameters can be combined to predict embryo quality. STUDY FUNDING/COMPETING INTERESTS: Funding was provided by Fertility Associates Ltd, the Auckland Medical Research Foundation and the University of Auckland. J.C.P. has a 0.5% shareholding in Fertility Associates. All other authors of this manuscript have nothing to declare and no conflict of interest that could be perceived as prejudicing the impartiality of the research reported.


Assuntos
Células do Cúmulo/metabolismo , Desenvolvimento Embrionário/genética , Expressão Gênica , Infertilidade Masculina/terapia , Injeções de Esperma Intracitoplásmicas , Adulto , Biomarcadores/metabolismo , Chaperona BiP do Retículo Endoplasmático , Feminino , Humanos , Masculino , Imagem com Lapso de Tempo
11.
Hum Reprod ; 30(6): 1410-20, 2015 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25820694

RESUMO

STUDY QUESTION: Does maternal ageing and ovarian stimulation alter mitochondrial DNA (mtDNA) copy number and gene expression of oocytes and cumulus cells from a novel bovine model for human IVF? SUMMARY ANSWER: Oocytes collected from females with identical nuclear genetics show decreased mtDNA copy number and increased expression of an endoplasmic reticulum (ER) stress gene with repect to ovarian stimulation, whilst differences in the expression of genes involved in mitochondrial function, antioxidant protection and apoptosis were evident in relation to maternal ageing and the degree of ovarian stimulation in cumulus cells. WHAT IS KNOWN ALREADY: Oocyte quality declines with advancing maternal age; however, the underlying mechanism, as well as the effects of ovarian stimulation are poorly understood. Human studies investigating these effects are often limited by differences in age and ovarian stimulation regimens within a patient cohort, as well as genetic and environmental variability. STUDY DESIGN, SIZE, DURATION: A novel bovine cross-sectional maternal age model for human IVF was undertaken. Follicles were aspirated from young (3 years of age; n = 7 females) and old (10 years of age; n = 5 females) Holstein Freisian clones following multiple unstimulated, mild and standard ovarian stimulation cycles. These bovine cloned females were generated by the process of somatic cell nuclear transfer (SCNT) from the same founder and represent a homogeneous population with reduced genetic and environmental variability. Maternal age and ovarian stimulation effects were investigated in relation to mtDNA copy number, and the expression of 19 genes involved in mitochondrial function, antioxidant protection, oocyte-cumulus cell signalling and follicle development in both oocytes and cumulus cells. MATERIALS, SETTING, METHODS: Young (3 years of age; n = 7 females) and old (10 years of age; n = 5 females) Holstein Freisian bovine clones were maintained as one herd. Stimulation cycles were based on the long GnRH agonist down-regulation regimen used in human fertility clinics. Follicle growth rates, numbers and diameters were monitored by ultrasonography and aspirated when the lead follicles were >14 mm in diameter. Follicle characteristics were analysed using a mixed model procedure. Quantitative PCR (qPCR) was used to determine mtDNA copy number and reverse transcriptase-qPCR (RT-qPCR) was used to measure gene expression in oocytes and cumulus cells. MAIN RESULTS AND THE ROLE OF CHANCE: Method of ovarian stimulation (P = 0.04), but not maternal age (P > 0.1), was associated with a lower mtDNA copy number in oocytes. Neither factor affected mtDNA copy number in cumulus cells. In oocytes, maternal age had no effect on gene expression; however, ovarian stimulation in older females increased the expression of GRP78 (P = 0.02), a gene involved in ER stress. In cumulus cells, increasing maternal age was associated with the higher expression of genes involved in mitochondrial maintenance (TXN2 P = 0.008 and TFAM P = 0.03), whereas ovarian stimulation decreased the expression of genes involved in mitochondrial oxidative stress and apoptosis (TXN2 P = 0.002, PRDX3 P = 0.03 and BAX P = 0.03). LIMITATIONS, REASON FOR CAUTION: The low number of oocyte and cumulus cell samples collected from the unstimulated cycles limited the analysis. Fertilization and developmental potential of the oocytes was not assessed because these were used for mtDNA and gene expression quantification. WIDER IMPLICATIONS OF THE FINDINGS: Delineation of the independent effects of maternal age and ovarian stimulation regimen on mtDNA copy number gene expression in oocytes and cumulus cells was enabled by the removal of genetic and environmental variability in this bovine model for human IVF. Therefore, these extend upon previous knowledge and findings provide relevant insights that are applicable for improving human ovarian stimulation regimens. STUDY FUNDING/COMPETING INTERESTS: Funding was provided by Fertility Associates and the University of Auckland. J.C.P. is a shareholder of Fertility Associates and M.P.G. received a fellowship from Fertility Associates. The other authors of this manuscript declare no conflict of interest that could be perceived as prejudicing the impartiality of the reported research.


Assuntos
Células do Cúmulo/metabolismo , DNA Mitocondrial/genética , Regulação da Expressão Gênica no Desenvolvimento , Idade Materna , Indução da Ovulação , Animais , Bovinos , Clonagem de Organismos , Estudos Transversais , Variações do Número de Cópias de DNA , Retículo Endoplasmático/metabolismo , Chaperona BiP do Retículo Endoplasmático , Feminino , Fertilização in vitro , Folículo Ovariano/crescimento & desenvolvimento
12.
Gynecol Oncol ; 133(2): 382-7, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24342437

RESUMO

OBJECTIVE: It has been four years since the discovery of the FOXL2 402C>G mutation in adult ovarian granulosa cell tumours. Yet to date, there have been few studies which have investigated the precise role of the mutation in tumour pathogenesis. This review aims to summarise the research in this area, proposes a mechanism of action for the mutation, and explores the implications for clinical practice and future therapeutics. METHODS: A literature search was performed with the keywords 'granulosa cell tumour' and 'FOXL2' on PubMed. RESULTS: Although the search returned 52 articles, of these only nine publications investigate the pathogenic effect of the mutant FOXL2 allele. Mutant FOXL2 maintains some of the transcriptional activity of the wildtype allele, but there is a subtle alteration of the expression in a unique suite of cancer-related genes. The mutation appears to deregulate the anti-proliferative transforming growth factor beta (TGF-ß) pathway and this may contribute to the pathogenesis of adult GCTs. The inability of mutant FOXL2 to elicit an effective apoptotic signalling cascade may also be important in GCT pathogenesis. CONCLUSION: The 402C>G mutation in FOXL2 is central to the development of adult granulosa cell tumours. Based on the evidence, we suggest that FOXL2 is an oncogene or tumour suppressor depending on the genetic context that is the GCT subtype.


Assuntos
Fatores de Transcrição Forkhead/genética , Tumor de Células da Granulosa/genética , Neoplasias Ovarianas/genética , Transdução de Sinais , Adulto , Apoptose , Feminino , Proteína Forkhead Box L2 , Humanos , Mutação , Fator de Crescimento Transformador beta
14.
Gynecol Oncol ; 131(2): 325-9, 2013 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-24007948

RESUMO

OBJECTIVES: The aim of this research was to use nucleic acids isolated from formalin-fixed paraffin-embedded (FFPE) tissue to investigate the diagnostic potential and prognostic significance of FOXL2 in adult-type GCTs, particularly as a marker of identifying early stage patients that are likely to relapse. METHODS: We performed a retrospective review of GCT patients referred to the Auckland Gynae-Oncology Multidisciplinary Team from 1955 to 2012. Baseline characteristics, clinical course, histopathology and survival data was recorded. Using nucleic acids extracted from FFPE tumour blocks, FOXL2 mutation status and expression was determined by DNA sequencing and RT-qPCR, respectively, and correlated with clinical data. RESULTS: 57 adult GCT patients were identified, however FFPE tumour blocks were available for only 37 of these patients. Sequencing results confirmed the presence of the FOXL2 mutation in 70% of patients. FOXL2 mutation positive adult tumours showed a trend towards higher FOXL2 expression than wildtype adult tumours, particularly in stage I patients (p=0.051). In addition, patients with homozygous FOXL2 mutations had a significantly higher relapse rate (p=0.04). There was no significant correlation between FOXL2 mutation status or FOXL2 expression and any other clinical variables. CONCLUSIONS: FFPE tumour blocks are a valuable resource of molecular information, especially when studying rare tumours such as GCTs. The FOXL2 mutation appears to have some diagnostic potential, however additional work in a larger cohort needs to be completed to confirm the prognostic significance of this gene mutation, and its expression.


Assuntos
Fatores de Transcrição Forkhead/genética , Tumor de Células da Granulosa/genética , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/biossíntese , Biomarcadores Tumorais/genética , Análise Mutacional de DNA , Intervalo Livre de Doença , Feminino , Proteína Forkhead Box L2 , Fatores de Transcrição Forkhead/biossíntese , Formaldeído , Tumor de Células da Granulosa/metabolismo , Tumor de Células da Granulosa/patologia , Humanos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Inclusão em Parafina , RNA Mensageiro/biossíntese , RNA Mensageiro/genética , Estudos Retrospectivos , Fixação de Tecidos , Adulto Jovem
15.
Reprod Biomed Online ; 26(4): 396-9, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23419799

RESUMO

FSH receptor (FSHR) gene variants have been associated with premature ovarian failure (POF). Genomic DNA from New Zealand women with POF (n=80) and control women (n=80) was screened for variants in FSHR exons 7 and 10. FSHR exon 7 variants, including the c.566C>T Finnish founder mutation (p.Ala189Val), were not detected. Previously reported FSHR exon 10 polymorphisms were identified in both groups with similar allelic distributions. A novel heterozygous FSHR exon 10 variant c.1411A>T, p.Ile471Phe was observed in one woman with a family history of POF, but not her affected siblings. It is concluded that variants in exons 7 and 10 of FSHR are not frequently associated with the development of POF in the New Zealand population.


Assuntos
Variação Genética , Insuficiência Ovariana Primária/genética , Receptores do FSH/genética , Éxons , Feminino , Humanos , Nova Zelândia
16.
Antioxidants (Basel) ; 12(8)2023 Aug 11.
Artigo em Inglês | MEDLINE | ID: mdl-37627595

RESUMO

Premature ovarian insufficiency (POI) is a condition that arises from dysfunction or early depletion of the ovarian follicle pool accompanied by an earlier-than-normal loss of fertility in young women. Oxidative stress has been suggested as an important factor in the decline of fertility in women and POI. In this review, we discuss the mechanisms of oxidative stress implicated in ovarian ageing and dysfunction in relation to POI, in particular mitochondrial dysfunction, apoptosis and inflammation. Genetic defects, autoimmunity and chemotherapy, are some of the reviewed hallmarks of POI that can lead to increased oxidative stress. Additionally, we highlight lifestyle factors, including diet, low energy availability and BMI, that can increase the risk of POI. The final section of this review discusses dietary factors associated with POI, including consumption of oily fish, mitochondria nutrient therapy, melatonin, dairy and vitamins that can be targeted as potential interventions, especially for at-risk women and in combination with personalised nutrition. Understanding the impact of lifestyle and its implications for POI and oxidative stress holds great promise in reducing the burden of this condition.

17.
BMC Cancer ; 12: 141, 2012 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-22475322

RESUMO

BACKGROUND: The phosphatidylinositol-3-kinase (PI3K-PKB), mitogen activated protein kinase (MEK-ERK) and the mammalian target of rapamycin (mTOR- p70S6K), are thought to regulate many aspects of tumour cell proliferation and survival. We have examined the utilisation of these three signalling pathways in a number of cell lines derived from patients with metastatic malignant melanoma of known PIK3CA, PTEN, NRAS and BRAF mutational status. METHODS: Western blotting was used to compare the phosphorylation status of components of the PI3K-PKB, MEK-ERK and mTOR-p70S6K signalling pathways, as indices of pathway utilisation. RESULTS: Normal melanocytes could not be distinguished from melanoma cells on the basis of pathway utilisation when grown in the presence of serum, but could be distinguished upon serum starvation, where signalling protein phosphorylation was generally abrogated. Surprisingly, the differential utilisation of individual pathways was not consistently associated with the presence of an oncogenic or tumour suppressor mutation of genes in these pathways. CONCLUSION: Utilisation of the PI3K-PKB, MEK-ERK and mTOR-p70S6K signalling pathways in melanoma, as determined by phosphorylation of signalling components, varies widely across a series of cell lines, and does not directly reflect mutation of genes coding these components. The main difference between cultured normal melanocytes and melanoma cells is not the pathway utilisation itself, but rather in the serum dependence of pathway utilisation.


Assuntos
Melanócitos/metabolismo , Melanoma/metabolismo , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Fosfatidilinositol 3-Quinase/metabolismo , Transdução de Sinais/fisiologia , Serina-Treonina Quinases TOR/metabolismo , Western Blotting , Linhagem Celular Tumoral , Classe I de Fosfatidilinositol 3-Quinases , Genes ras/genética , Humanos , PTEN Fosfo-Hidrolase/genética , Fosfatidilinositol 3-Quinases/genética , Fosforilação , Proteínas Proto-Oncogênicas B-raf/genética
18.
J Biomed Biotechnol ; 2012: 350352, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22500088

RESUMO

The zebrafish (Danio rerio) has become an attractive model for human disease modeling as there are a large number of orthologous genes that encode similar proteins to those found in humans. The number of tools available to manipulate the zebrafish genome is limited and many currently used techniques are only effective during early development (such as morpholino-based antisense technology) or it is phenotypically driven and does not offer targeted gene knockdown (such as chemical mutagenesis). The use of RNA interference has been met with controversy as off-target effects can make interpreting phenotypic outcomes difficult; however, this has been resolved by creating zebrafish lines that contain stably integrated miRNA constructs that target the desired gene of interest. In this study, we show that a commercially available miRNA vector system with a mouse-derived miRNA backbone is functional in zebrafish and is effective in causing eGFP knockdown in a transient in vivo eGFP sensor assay system. We chose to apply this system to the knockdown of transcripts that are implicated in the human cardiac disorder, Long QT syndrome.


Assuntos
Técnicas de Silenciamento de Genes/métodos , MicroRNAs/genética , Proteínas de Peixe-Zebra/genética , Análise de Variância , Animais , Modelos Animais de Doenças , Embrião não Mamífero , Canais de Potássio Éter-A-Go-Go/genética , Canais de Potássio Éter-A-Go-Go/metabolismo , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Humanos , Síndrome do QT Longo , Camundongos , MicroRNAs/química , Interferência de RNA , Peixe-Zebra , Proteínas de Peixe-Zebra/metabolismo
19.
J Fam Plann Reprod Health Care ; 38(4): 239-45, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22241766

RESUMO

OBJECTIVES: Little is known about the ethnic differences in disease presentation of uterine cancer in New Zealand women. The objectives of this study were two-fold: (1) to estimate the incidence and mortality of uterine cancer among women in New Zealand and (2) to examine the association of ethnicity and socioeconomic status with tumour stage and grade, at presentation of uterine cancer. METHODS: Retrospective survey of cancer cases identified from the New Zealand Cancer Registry. The authors analysed all 3203 uterine cancer cases registered with the New Zealand Cancer Registry during the period 1 January 1997 to 31 December 2006. Ethnic groups were defined based on the self-identified ethnicity recorded on the cancer registry: Ma-ori, Pacific and non-Maori non-Pacific women. Socioeconomic status was categorised as quintiles of the New Zealand Deprivation Index 2006. The mortality to incidence ratio was used as a measure of prognosis. Logistic regression was used to estimate age, ethnic and deprivation adjusted odds ratios (ORs) and 95% confidence intervals (CIs). RESULTS: Pacific and Maori women have higher incidence (32.4 and 17.7 per 100 000 women, respectively) and mortality rates of uterine cancer (12.1 and 7.4 per 100 000 women, respectively). Women in the most deprived areas are more likely to present with an advanced stage of uterine cancer (OR 1.64, 95% CI 1.09-2.48). Maori and Pacific women are less likely to present with well-differentiated tumours (OR 0.69, 95% CI 0.52-0.92 and OR 0.72, 95% CI 0.52-0.99, respectively). CONCLUSIONS: Maori and Pacific women, and those from lower socioeconomic areas, are more likely to present with advanced uterine cancer.


Assuntos
Havaiano Nativo ou Outro Ilhéu do Pacífico , Neoplasias Uterinas/etnologia , Neoplasias Uterinas/mortalidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Incidência , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Nova Zelândia/epidemiologia , Nova Zelândia/etnologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Fatores Socioeconômicos , Neoplasias Uterinas/patologia , Adulto Jovem
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