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1.
Autophagy ; 20(6): 1383-1397, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38436206

RESUMO

BRAFV600E is the most prevalent mutation in thyroid cancer and correlates with poor prognosis and therapy resistance. Although selective inhibitors of BRAFV600E have been developed, more advanced tumors such as anaplastic thyroid carcinomas show a poor response in clinical trials. Therefore, the study of alternative survival mechanisms is needed. Since metabolic changes have been related to malignant progression, in this work we explore metabolic dependencies of thyroid tumor cells to exploit them therapeutically. Our results show that respiration of thyroid carcinoma cells is highly dependent on fatty acid oxidation and, in turn, fatty acid mitochondrial availability is regulated through macroautophagy/autophagy. Furthermore, we show that both lysosomal inhibition and the knockout of the essential autophagy gene, ATG7, lead to enhanced lipolysis; although this effect is not essential for survival of thyroid carcinoma cells. We also demonstrate that following inhibition of either autophagy or fatty acid oxidation, thyroid tumor cells compensate oxidative phosphorylation deficiency with an increase in glycolysis. In contrast to lipolysis induction, upon autophagy inhibition, glycolytic boost in autophagy-deficient cells is essential for survival and, importantly, correlates with a higher sensitivity to the BRAFV600E selective inhibitor, vemurafenib. In agreement, downregulation of the glycolytic pathway results in enhanced mitochondrial respiration and vemurafenib resistance. Our work provides new insights into the role of autophagy in thyroid cancer metabolism and supports mitochondrial targeting in combination with vemurafenib to eliminate BRAFV600E-positive thyroid carcinoma cells.Abbreviations: AMP: adenosine monophosphate; ATC: anaplastic thyroid carcinoma; ATG: autophagy related; ATP: adenosine triphosphate; BRAF: B-Raf proto-oncogene, serine/threonine kinase; Cas9: CRISPR-associated protein; CREB: cAMP responsive element binding protein; CRISPR: clustered regularly interspaced short palindromic repeats; 2DG: 2-deoxyglucose; FA: fatty acid; FAO: fatty acid oxidation; FASN: fatty acid synthase; FCCP: trifluoromethoxy carbonyl cyanide phenylhydrazone; LAMP1: lysosomal associated membrane protein 1; LIPE/HSL: lipase E, hormone sensitive type; MAP1LC3/LC3: microtubule associated protein 1 light chain 3; OCR: oxygen consumption rate; OXPHOS: oxidative phosphorylation; PRKA/PKA: protein kinase cAMP-activated; PTC: papillary thyroid carcinoma; SREBF1/SREBP1: sterol regulatory element binding transcription factor 1.


Assuntos
Autofagia , Resistencia a Medicamentos Antineoplásicos , Mitocôndrias , Proteínas Proto-Oncogênicas B-raf , Neoplasias da Glândula Tireoide , Humanos , Autofagia/efeitos dos fármacos , Autofagia/genética , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/genética , Neoplasias da Glândula Tireoide/metabolismo , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Linhagem Celular Tumoral , Proteínas Proto-Oncogênicas B-raf/metabolismo , Proteínas Proto-Oncogênicas B-raf/genética , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Resistencia a Medicamentos Antineoplásicos/genética , Ácidos Graxos/metabolismo , Glicólise/efeitos dos fármacos , Proto-Oncogene Mas , Vemurafenib/farmacologia , Lipólise/efeitos dos fármacos , Respiração Celular/efeitos dos fármacos , Proteína 7 Relacionada à Autofagia/metabolismo , Proteína 7 Relacionada à Autofagia/genética , Sulfonamidas/farmacologia , Fosforilação Oxidativa/efeitos dos fármacos , Lisossomos/metabolismo , Lisossomos/efeitos dos fármacos , Indóis/farmacologia
2.
Clin Transl Oncol ; 26(5): 1129-1138, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-37872422

RESUMO

PURPOSE: Currently, 15% of gynaecological and 9% of haematological malignancies are diagnosed before the age of 40. The increased survival rates of cancer patients who are candidates for gonadotoxic treatments, the delay in childbearing to older ages, and the optimization of in vitro fertilisation techniques have all contributed to an increased interest in fertility preservation (FP) treatments. This study reviews the experience of the Fertility Preservation Programme (FPP) of a tertiary public hospital with a multidisciplinary approach. METHODS: This retrospective study included all the available (FP) treatments, performed in patients of childbearing age between 2006 and 2022. RESULTS: 1556 patients were referred to the FPP: 332 oocyte vitrification cycles, 115 ovarian cortex cryopreservation with 11 orthotopic autotransplantations, 175 gonadotropin-releasing hormone (GnRH) agonist treatments, 109 fertility-sparing treatments for gynaecological cancer, and 576 sperm cryopreservation were performed. Malignancy was the main indication for FP (the main indications being breast cancer in women and haematological malignancies in men), although non-oncological pathologies, such as endometriosis and autoimmune diseases, have increased in recent years. Currently, the most widely used FP technique is oocyte vitrification, the increase of which has been associated with a decrease in the use of cortex CP and GnRH agonists. CONCLUSIONS: The increase in FP treatment reflects the implementation of reproductive counselling in oncology programmes. A multidisciplinary approach in a tertiary public hospital allows individualised FP treatment for each patient. In recent years, there has been a change in trend with the introduction of new indications for FP and a change in techniques due to their optimisation.

3.
J Assist Reprod Genet ; 39(2): 527-541, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35098405

RESUMO

PURPOSE: The use of fertility preservation (FP) techniques has significantly increased in recent years in the assigned female at birth (AFAB) transgender population. Oocyte cryopreservation is the established method for FP, but ovarian tissue cryopreservation may be considered an alternative option, especially during gender-affirming surgery (GAS). The slow freezing (SF) cryopreservation technique is the standard method for human ovarian tissue, but recently, several studies have shown good results with the vitrification (VT) technique. The objective of this study was to compare the effectiveness of VT and SF techniques in ovarian tissue from AFAB transgender people. METHODS: This was a prospective study including 18 AFAB transgender people after GAS. Ovarian tissue pieces from each ovary were cryopreserved by SF and VT and compared with fresh tissue. Study by light microscopy (LM) assessed follicular morphology and density. The percentage of surviving and degenerated follicles was studied with the tissue viability test. Oocytes, granulosa cells and stroma were analysed separately by transmission electron microscopy. RESULTS: The VT technique preserves follicle and stromal tissue as well as the SF method, but with some differences. Evaluation by LM showed better follicle preservation with VT, but the ultrastructural study showed the presence of minor damage with both techniques compared to fresh tissue. CONCLUSION: Both cryopreservation techniques are accurate for maintaining the follicular population and stromal tissue. Further studies are needed to determine the impact of VT on ovarian tissue and the subsequent follicular activation mechanisms in AFAB ovarian tissue.


Assuntos
Pessoas Transgênero , Vitrificação , Criopreservação/métodos , Feminino , Congelamento , Humanos , Estudos Prospectivos , Testosterona
4.
Reprod Biomed Online ; 40(5): 700-710, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32444165

RESUMO

RESEARCH QUESTION: Do alterations of human sperm protein profile affect embryo quality? DESIGN: Sperm proteins from 27 infertile couples undergoing intracytoplasmic sperm injection (ICSI) were extracted and digested. The resulting peptides were labelled using tandem mass tags, separated by two-dimensional liquid chromatography, and identified and quantified using tandem mass spectrometry. Subsequently, sperm protein and peptide abundance were statistically analysed for correlation with ICSI-derived embryo quality in the subset of idiopathic infertile couples. Detected correlations were further assessed in the subset of infertile patients with a known factor. RESULTS: The abundance of 18 individual sperm proteins was found to correlate with embryo quality after ICSI. Of note, a high percentage of poor-quality ICSI-derived embryos was associated with alterations in several components of the eight-membered chaperonin-containing T-complex, which plays an important role in the folding of many essential proteins. Additionally, the abundance of sperm proteins with known functions in embryogenesis, such as RUBVL1, also correlated with early embryo quality (r = -0.547; P = 0.028). Some of the correlations found in this study were validated using either proteomic data from infertile patients with a known factor or data from similar published studies. Analysis at the peptide level revealed the association of some correlations with specific post-translational modifications or isoforms. CONCLUSIONS: Our results support the hypothesis that the sperm proteome plays a role in early embryogenesis. Moreover, several sperm proteins have emerged as potential biomarkers that could predict the outcome of in-vitro assisted reproductive technologies, leading to the possibility of improved diagnosis of couples with idiopathic infertility.


Assuntos
Desenvolvimento Embrionário/fisiologia , Proteoma , Injeções de Esperma Intracitoplásmicas , Espermatozoides/metabolismo , Adulto , Fragmentação do DNA , Transferência Embrionária , Feminino , Fertilização in vitro , Humanos , Masculino , Gravidez , Taxa de Gravidez , Proteômica
5.
Reprod Biomed Online ; 40(2): 254-260, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31956062

RESUMO

RESEARCH QUESTION: Could in-vitro action of follicles and fresh tissue autotransplantation without tissue culture (drug-free IVA) be useful in patients with primary ovarian insufficiency (POI)? DESIGN: Prospective observational cohort study in a tertiary university hospital. Drug-Free IVA was carried out in 14 women with POI with a median age of 33 years (29-36 years), median length of amenorrhoea of 1.5 years (1-11 years), median FSH levels 69.2 mIU/ml (36.9-82.8 mIU/ml) and anti-Müllerian hormone of 0.02 ng/ml (0.01-0.1 ng/ml). The surgical procedure included laparoscopic removal of ovarian cortex, fragmentation of tissue and autografting. Human menopausal gonadotrophin (HMG) was started immediately after surgery. RESULTS: Follicle development was detected in seven out of the 14 patients, and five women achieved successful oocyte retrieval. In six women, HCG was administered in 10 cycles. Six embryo transfers were carried out in five women resulting in four pregnancies; a clinical pregnancy rate of four in seven oocyte retrievals and four in six embryo transfers. CONCLUSIONS: Drug-free IVA could be a useful therapeutic option for patients with POI, leading to successful IVF outcomes.


Assuntos
Recuperação de Oócitos , Ovário/transplante , Indução da Ovulação/métodos , Insuficiência Ovariana Primária/terapia , Transplante Autólogo/métodos , Adulto , Hormônio Antimülleriano/sangue , Transferência Embrionária , Feminino , Hormônio Foliculoestimulante/sangue , Humanos , Gravidez , Taxa de Gravidez , Insuficiência Ovariana Primária/sangue
6.
Front Endocrinol (Lausanne) ; 11: 617704, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33716954

RESUMO

Usually poor ovarian response (POR) to gonadotropins reflects a diminished ovarian reserve (DOR) that gives place to few recruitable follicles despite aggressive stimulation. The reduction in the quantity and quality of the oocytes with advanced age is physiological. However, some women experience DOR much earlier and become prematurely infertile, producing an accelerated follicular depletion towards primary ovarian insufficiency (POI). Up to now, egg donation has been commonly used to treat their infertility. In the last thirty years, specialists in assisted reproduction have focused their attention on the final stages of folliculogenesis, those that depend on the action of gonadotrophins. Nevertheless, recently novel aspects have been known to act in the initial phases, with activating and inhibiting elements. In vitro activation (IVA) combining the in vitro stimulation of the ovarian Akt signaling pathway in ovarian cortex fragments with a method named Hippo-signaling disruption. Later, a simplification of the technique designated Drug-Free IVA have shown encouraging results in patients with POI. Another innovative therapeutic option in these patients is the infusion of bone marrow-derived stem cells (BMDSC) in order to supply an adequate ovarian niche to maintain and/or promote follicular rescue in patients with impaired or aged ovarian reserves. In this review, for the first time, both therapeutic options are addressed together in a common clinical setting. The aim of this review is to analyze the physiological aspects on which these innovative techniques are based; the preliminary results obtained up to now; and the possible therapeutic role that they may have in the future with DOR and POI patients.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Folículo Ovariano/metabolismo , Reserva Ovariana/fisiologia , Insuficiência Ovariana Primária/metabolismo , Insuficiência Ovariana Primária/terapia , Animais , Feminino , Humanos , Transplante de Células-Tronco Mesenquimais/tendências , Células-Tronco Mesenquimais/metabolismo , Transplante de Células-Tronco/métodos , Transplante de Células-Tronco/tendências
7.
Fertil Steril ; 81(5): 1366-70, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15136103

RESUMO

OBJECTIVE: To investigate the effect on embryo transfer (ET) success of air loaded into the transfer catheter to bracket the embryo-containing medium. DESIGN: Prospective, randomized study. SETTING: University teaching hospital. PATIENT(S): One hundred two consecutive patients undergoing ET after IVF. INTERVENTION(S): In group 1 (n = 52), embryos were loaded as follows: 200 microL of air in the syringe, 100-125 microL of air in the proximal part of the catheter, 20-25 microL of medium containing the embryos to be transferred, and 10 microL of air at the tip of the catheter. In group 2 (n = 50), the syringe and the entire catheter were filled with medium and the embryo-containing medium (20-25 microL) was aspirated without being bracketed by air spaces. MAIN OUTCOME MEASURE(S): Implantation and pregnancy rates. RESULT(S): No differences were found between groups 1 and 2 with respect to implantation and pregnancy rates. CONCLUSION(S): The air loaded into the transfer catheter to bracket the embryo-containing medium has no negative effect on ET success.


Assuntos
Transferência Embrionária , Ar , Feminino , Fertilização in vitro , Humanos , Masculino , Estudos Prospectivos , Injeções de Esperma Intracitoplásmicas
8.
J Assist Reprod Genet ; 20(12): 521-6, 2003 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-15035553

RESUMO

PURPOSE: To investigate the relative power of HCG, estradiol, and progesterone determinations in the prediction of pregnancy outcome after IVF. These prognostic hormonal factors were studied as single and combined predictors. METHODS: Serum concentrations of beta-HCG, progesterone, and estradiol were measured 12-13 days after embryo transfer (study point 1) and 7 days later (study point 2) in a series of 20 consecutive infertile patients having a first-trimester spontaneous clinical abortion after an IVF-embryo transfer cycle. As a control group (n = 60), the next three IVF-embryo transfer cycles resulting in an ongoing pregnancy after each miscarried IVF cycle in our assisted reproduction program was used. The discrimination attained between the two study groups (ongoing pregnancies and miscarriages) was evaluated by logistic regression and receiver operating characteristic (ROC) curve analysis. RESULTS: Mean hormone concentrations at study points 1 and 2 were higher in the ongoing pregnancy than in the abortion group. Regarding pregnancy outcome the percentage increment of HCG serum levels (> or = 1321%), with an accuracy (predictive value of pregnancy outcome) of 81.2% (sensitivity 98%, specificity 50%), had the best prognostic reliability but no significant differences were found when this parameter was compared with the predictive value of HCG concentration (> or = 72 IU/l) at study point 1 (diagnostic accuracy 80.5%; sensitivity 70%; specificity 80%). When ROC analysis was used, the best predictor of ongoing pregnancy according to the AUC(ROC) was HCG concentration at study point 2 but again no significant differences were found when this parameter was compared with the predictive value of HCG serum levels at study point 1. A multiple marker strategy did not help distinguish viable from nonviable pregnancies. CONCLUSION: A single, early (days 12-13 after embryo transfer) HCG quantitative serum measurement in IVF cycles not only is diagnostic but also has good predictive value for pregnancy outcome.


Assuntos
Gonadotropina Coriônica/sangue , Estradiol/sangue , Resultado da Gravidez , Progesterona/sangue , Adulto , Biomarcadores , Transferência Embrionária , Feminino , Fertilização in vitro , Humanos , Gravidez , Fatores de Tempo
9.
Am J Reprod Immunol ; 50(5): 420-6, 2003 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-14750701

RESUMO

PROBLEM: The majority of women with recurrent miscarriage have no discernible cause but it has been postulated that immunologic aberrations may be the cause in most of such cases. Also, it has been stressed that deliberate modification of the maternal host defense system can improve the chances of success. We tested the hypothesis that it is possible to potentiate maternal immune functions so as to improve reproductive performance by replacing several embryos into the uterus, thus favoring the recognition of fetal antigens. METHOD OF STUDY: A total of 57 couples with three or more (mean 5.52; range 3-12) consecutive first-trimester spontaneous clinical abortions of unknown etiology were treated with in vitro fertilization (IVF) and embryo transfer for a total of 84 cycles. Patients underwent IVF after combined gonadotropin-releasing hormone agonist/gonadotropin treatment for ovarian stimulation, and up to four embryos were replaced into the uterus. RESULTS: There were 32 pregnancies (three of them after frozen-thawed embryo transfers) and 26 (81%) of them were viable gestations. Overall, patients had a previous obstetric history of 315 pregnancy losses and 15 live-born babies. Thus, the probability of having a live baby before treatment was 4.54% (95% CI, 2.78-7.36) a figure significantly lower (P < 0.0001) than that observed under IVF treatment (81%; 95% CI, 64.53-91.01). None of selected variables potentially related with the outcome of pregnancy after IVF and embryo transfer in recurrent aborters (including pre-implantation genetic diagnosis) was found to be associated with miscarriage. CONCLUSIONS: This study shows that replacement of several embryos after IVF is a useful treatment in the prevention of unexplained recurrent spontaneous abortion thus providing further evidence for immunologically modifiable pregnancy loss.


Assuntos
Aborto Habitual/imunologia , Aborto Habitual/terapia , Transferência Embrionária , Fertilização in vitro , Adulto , Humanos
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