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1.
EMBO J ; 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38565949

RESUMO

The Hippo pathway effectors Yes-associated protein 1 (YAP) and its homolog TAZ are transcriptional coactivators that control gene expression by binding to TEA domain (TEAD) family transcription factors. The YAP/TAZ-TEAD complex is a key regulator of cancer-specific transcriptional programs, which promote tumor progression in diverse types of cancer, including breast cancer. Despite intensive efforts, the YAP/TAZ-TEAD complex in cancer has remained largely undruggable due to an incomplete mechanistic understanding. Here, we report that nuclear phosphoinositides function as cofactors that mediate the binding of YAP/TAZ to TEADs. The enzymatic products of phosphoinositide kinases PIPKIα and IPMK, including phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) and phosphatidylinositol 3,4,5-trisphosphate (P(I3,4,5)P3), bridge the binding of YAP/TAZ to TEAD. Inhibiting these kinases or the association of YAP/TAZ with PI(4,5)P2 and PI(3,4,5)P3 attenuates YAP/TAZ interaction with the TEADs, the expression of YAP/TAZ target genes, and breast cancer cell motility. Although we could not conclusively exclude the possibility that other enzymatic products of IPMK such as inositol phosphates play a role in the mechanism, our results point to a previously unrecognized role of nuclear phosphoinositide signaling in control of YAP/TAZ activity and implicate this pathway as a potential therapeutic target in YAP/TAZ-driven breast cancer.

2.
J Neuroendocrinol ; : e13371, 2024 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-38404024

RESUMO

The roles of initially kisspeptin and subsequently neurokinin B pathways in the regulation of human reproduction through the control of GnRH secretion were first identified 20 years ago, as essential for the onset of puberty in both boys and girls. Within that short time we already now have the first licence for clinical use for a neurokinin antagonist in a related indication, for menopausal vasomotor symptoms. Between these two markers of the start and end of the reproductive lifespan, it is clear that these pathways underlie many of the aspects of the hypothalamic regulation of reproduction which had hitherto been enigmatic. In this review, we describe the data currently available from studies designed to elucidate the roles of kisspeptin and neurokinin B in human ovarian function, specifically the regulation of follicle development leading up to ovulation, and in the control of the mid-cycle GnRH/LH surge that triggers ovulation. These studies, undertaken with only very limited pharmacological tools, provide evidence that the neurokinin B pathway is important in controlling the hypothalamic contribution to the precise gonadotropic drive to the ovary that is necessary for mono-ovulation, whereas the switch from negative to positive estrogenic feedback results in kisspeptin-mediated increased GnRH secretion. Potential therapeutic opportunities in conditions characterised by disordered hypothalamic/pituitary function, polycystic ovary syndrome, and functional hypothalamic amenorrhoea, and in the induced LH surge that is a necessary part of IVF treatment are discussed.

3.
Expert Opin Investig Drugs ; 33(1): 19-26, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38224099

RESUMO

INTRODUCTION: Menopausal vasomotor symptoms (VMS) are experienced by most women and are often debilitating and can last for years. While hormone replacement therapy is effective, it carries risks that have impacted its wider use, and it can be contraindicated. There is a large unmet need for a safe, effective non-hormonal therapy. AREAS COVERED: The importance of the neurokinin (NK) system in the hypothalamic regulation of the vasomotor center has become clear. NK antagonists, previously developed for other indications, have therefore been investigated for the treatment of VMS. Elinzanetant is a potent antagonist at both NK1 (endogenous ligand Substance P) and NK3 (neurokinin B) receptors, whereas other related drugs in development are selective NK3 antagonists. Elinzanetant has been investigated in 2 Phase II trials for menopausal VMS, demonstrating rapid onset and dose-dependant efficacy for the relief of VMS and improvement in quality of life for up to 12 weeks. Phase III trials are underway in women both with physiological menopause and after treatment for breast cancer. EXPERT OPINION: Elinzanetant is a very promising non-hormonal approach to a highly prevalent symptom constellation, with rapid onset and high efficacy. Wider indications are being explored in current Phase III trials.


Assuntos
Neoplasias da Mama , Fogachos , Humanos , Feminino , Fogachos/tratamento farmacológico , Pós-Menopausa/fisiologia , Qualidade de Vida , Menopausa/fisiologia
4.
Nat Rev Urol ; 21(2): 102-124, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-37828407

RESUMO

Currently, most men with infertility cannot be given an aetiology, which reflects a lack of knowledge around gamete production and how it is affected by genetics and the environment. A failure to recognize the burden of male infertility and its potential as a biomarker for systemic illness exists. The absence of such knowledge results in patients generally being treated as a uniform group, for whom the strategy is to bypass the causality using medically assisted reproduction (MAR) techniques. In doing so, opportunities to prevent co-morbidity are missed and the burden of MAR is shifted to the woman. To advance understanding of men's reproductive health, longitudinal and multi-national centres for data and sample collection are essential. Such programmes must enable an integrated view of the consequences of genetics, epigenetics and environmental factors on fertility and offspring health. Definition and possible amelioration of the consequences of MAR for conceived children are needed. Inherent in this statement is the necessity to promote fertility restoration and/or use the least invasive MAR strategy available. To achieve this aim, protocols must be rigorously tested and the move towards personalized medicine encouraged. Equally, education of the public, governments and clinicians on the frequency and consequences of infertility is needed. Health options, including male contraceptives, must be expanded, and the opportunities encompassed in such investment understood. The pressing questions related to male reproductive health, spanning the spectrum of andrology are identified in the Expert Recommendation.


Assuntos
Infertilidade Masculina , Humanos , Feminino , Criança , Masculino , Infertilidade Masculina/epidemiologia , Infertilidade Masculina/etiologia , Fertilidade , Técnicas de Reprodução Assistida , Saúde do Homem , Morbidade
5.
J Hazard Mater ; 465: 133080, 2024 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-38091799

RESUMO

Environmental pollution stands as one of the most critical challenges affecting human health, with an estimated mortality rate linked to pollution-induced non-communicable diseases projected to range from 20% to 25%. These pollutants not only disrupt immune responses but can also trigger immunotoxicity. Phosphoinositide signaling, a pivotal regulator of immune responses, plays a central role in the development of autoimmune diseases and exhibits high sensitivity to environmental stressors. Among these stressors, environmental pollutants have become increasingly prevalent in our society, contributing to the initiation and exacerbation of autoimmune conditions. In this review, we summarize the intricate interplay between phosphoinositide signaling and autoimmune diseases within the context of environmental pollutants and contaminants. We provide an up-to-date overview of stress-induced phosphoinositide signaling, discuss 14 selected examples categorized into three groups of environmental pollutants and their connections to immune diseases, and shed light on the associated phosphoinositide signaling pathways. Through these discussions, this review advances our understanding of how phosphoinositide signaling influences the coordinated immune response to environmental stressors at a biological level. Furthermore, it offers valuable insights into potential research directions and therapeutic targets aimed at mitigating the impact of environmental pollutants on the pathogenesis of autoimmune diseases. SYNOPSIS: Phosphoinositide signaling at the intersection of environmental pollutants and autoimmunity provides novel insights for managing autoimmune diseases aggravated by pollutants.


Assuntos
Doenças Autoimunes , Poluentes Ambientais , Humanos , Autoimunidade , Poluentes Ambientais/toxicidade , Doenças Autoimunes/etiologia , Doenças Autoimunes/patologia , Poluição Ambiental , Transdução de Sinais
6.
Hum Reprod ; 39(2): 382-392, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38070496

RESUMO

STUDY QUESTION: What are the effects of cyclophosphamide exposure on the human ovary and can anti-Mullerian hormone (AMH) and rapamycin protect against these? SUMMARY ANSWER: Exposure to cyclophosphamide compromises the health of primordial and transitional follicles in the human ovarian cortex and upregulates PI3K signalling, indicating both direct damage and increased follicular activation; AMH attenuates both of these chemotherapy-induced effects, while rapamycin attenuates only PI3K signalling upregulation. WHAT IS KNOWN ALREADY: Studies primarily in rodents demonstrate that cyclophosphamide causes direct damage to primordial follicles or that the primordial follicle pool is depleted primarily through excessive initiation of follicle growth. This increased follicular activation is mediated via upregulated PI3K signalling and/or reduced local levels of AMH production due to lost growing follicles. Furthermore, while rodent data show promise regarding the potential benefits of inhibitors/protectants alongside chemotherapy treatment to preserve female fertility, there is no information about the potential for this in humans. STUDY DESIGN, SIZE, DURATION: Fresh ovarian cortical biopsies were obtained from 17 healthy women aged 21-41 years (mean ± SD: 31.8 ± 4.9 years) at elective caesarean section. Biopsies were cut into small fragments and cultured for 24 h with either vehicle alone (DMSO), the active cyclophosphamide metabolite 4-hydroperoxycyclophosphamide (4-HC) alone, 4-HC + rapamycin or 4-HC+AMH. Two doses of 4-HC were investigated, 0.2 and 2 µM in separate experiments, using biopsies from seven women (aged 27-41) and six women (aged 21-34), respectively. Biopsies from four women (aged 28-38) were used to investigate the effect of rapamycin or AMH only. PARTICIPANTS/MATERIALS, SETTING, METHODS: Histological analysis of ovarian tissue was undertaken for follicle staging and health assessment. Western blotting and immunostaining were used to assess activation of PI3K signalling by measuring phosphorylation of AKT and phosphorylated FOXO3A staining intensity, respectively. MAIN RESULTS AND THE ROLE OF CHANCE: Exposure to either dose of 4-HC caused an increase in the proportion of unhealthy primordial (P < 0.0001, both doses) and transitional follicles (P < 0.01 for low dose and P < 0.01 for high dose) compared to vehicle. AMH significantly reduced follicle damage by approximately half in both of the investigated doses of 4-HC (P < 0.0001), while rapamycin had no protective effect on the health of the follicles. Culture with AMH or rapamycin alone had no effect on follicle health. Activation of PI3K signalling following 4-HC exposure was demonstrated by both Western blotting data showing that 4-HC increased in AKT phosphorylation and immunostaining showing increased phosphorylated FOXO3A staining of non-growing oocytes. Treatment with rapamycin reduced the activation of PI3K signalling in experiments with low doses of 4-HC while culture with AMH reduced PI3K activation (both AKT phosphorylation and phosphorylated FOXO3A staining intensity) across both doses investigated. LIMITATIONS, REASONS FOR CAUTION: These in vitro studies may not replicate in vivo exposures. Furthermore, longer experiment durations are needed to determine whether the effects observed translate into irreparable deficits of ovarian follicles. WIDER IMPLICATIONS OF THE FINDINGS: These data provide a solid foundation on which to explore the efficacy of AMH in protecting non-growing ovarian follicles from gonadotoxic chemotherapies. Future work will require consideration of the sustained effects of chemotherapy treatment and potential protectants to ensure these agents do not impair the developmental competence of oocytes or lead to the survival of oocytes with accumulated DNA damage, which could have adverse consequences for potential offspring. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by grants from TENOVUS Scotland, the Academy of Medical Sciences (to R.R.), the Medical Research Council (G1100357 to R.A.A., MR/N022556/1 to the MRC Centre for Reproductive Health), and Merck Serono UK (to R.A.A.). R.R., H.L.S., N.S., and E.E.T. declare no conflicts of interest. R.A.A. reports grants and personal fees from Roche Diagnostics and Ferring Pharmaceuticals, and personal fees from IBSA and Merck outside the submitted work. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Hormônio Antimülleriano , Ovário , Humanos , Feminino , Gravidez , Ovário/patologia , Hormônio Antimülleriano/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Sirolimo/farmacologia , Sirolimo/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Cesárea , Ciclofosfamida/efeitos adversos
7.
Curr Biol ; 34(1): 117-131.e5, 2024 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-38134935

RESUMO

Aneuploid human eggs (oocytes) are a major cause of infertility, miscarriage, and chromosomal disorders. Such aneuploidies increase greatly as women age, with defective linkages between sister chromatids (cohesion) in meiosis as a common cause. We found that loss of a specific pool of the cohesin protector protein, shugoshin 2 (SGO2), may contribute to this phenomenon. Our data indicate that SGO2 preserves sister chromatid cohesion in meiosis by protecting a "cohesin bridge" between sister chromatids. In human oocytes, SGO2 localizes to both sub-centromere cups and the pericentromeric bridge, which spans the sister chromatid junction. SGO2 normally colocalizes with cohesin; however, in meiosis II oocytes from older women, SGO2 is frequently lost from the pericentromeric bridge and sister chromatid cohesion is weakened. MPS1 and BUB1 kinase activities maintain SGO2 at sub-centromeres and the pericentromeric bridge. Removal of SGO2 throughout meiosis I by MPS1 inhibition reduces cohesion protection, increasing the incidence of single chromatids at meiosis II. Therefore, SGO2 deficiency in human oocytes can exacerbate the effects of maternal age by rendering residual cohesin at pericentromeres vulnerable to loss in anaphase I. Our data show that impaired SGO2 localization weakens cohesion integrity and may contribute to the increased incidence of aneuploidy observed in human oocytes with advanced maternal age.


Assuntos
Proteínas de Ciclo Celular , Oócitos , Humanos , Feminino , Idoso , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Oócitos/metabolismo , 60634 , Meiose , Centrômero/metabolismo , Cromátides/metabolismo , Segregação de Cromossomos
8.
bioRxiv ; 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-38076785

RESUMO

With age, people tend to accumulate body fat and reduce energy expenditure 1 . Brown (BAT) and beige adipose tissue dissipate heat and increase energy expenditure via the activity of the uncoupling protein UCP1 and other thermogenic futile cycles 2,3 . The activity of brown and beige depots inversely correlates with BMI and age 4-11 , suggesting that promoting thermogenesis may be an effective approach for combating age-related metabolic disease 12-15 . Heme is an enzyme cofactor and signaling molecule that we recently showed to regulate BAT function 16 . Here, we show that heme biosynthesis is the primary contributor to intracellular heme levels in brown adipocytes. Inhibition of heme biosynthesis leads to mitochondrial dysfunction and reduction in UCP1. Although supplementing heme can restore mitochondrial function in heme-synthesis-deficient cells, the downregulation of UCP1 persists due to the accumulation of the heme precursors, particularly propionyl-CoA, which is a product of branched-chain amino acids (BCAA) catabolism. Cold exposure promotes BCAA uptake in BAT, and defects in BCAA catabolism in this tissue hinder thermogenesis 17 . However, BCAAs' contribution to the TCA cycle in BAT and WAT never exceeds 2% of total TCA flux 18 . Our work offers a way to integrate current literature by describing heme biosynthesis as an important metabolic sink for BCAAs.

9.
bioRxiv ; 2023 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-37961303

RESUMO

Reactive oxygen species (ROS) are generated by aerobic metabolism, and their deleterious effects are buffered by the cellular antioxidant response, which prevents oxidative stress. The nuclear factor erythroid 2-related factor 2 (NRF2) is a master transcriptional regulator of the antioxidant response. Basal levels of NRF2 are kept low by ubiquitin-dependent degradation of NRF2 by E3 ligases, including the Kelch-like ECH-associated protein 1 (KEAP1). Here, we show that the stability and function of NRF2 is regulated by the type I phosphatidylinositol phosphate kinase g (PIPKIg), which binds NRF2 and transfers its product phosphatidylinositol 4,5-bisphosphate (PtdIns(4,5)P 2 ) to NRF2. PtdIns(4,5)P 2 binding recruits the small heat shock protein HSP27 to the complex. Silencing PIPKIg or HSP27 destabilizes NRF2, reduces expression of its target gene HO-1, and sensitizes cells to oxidative stress. These data demonstrate an unexpected role of phosphoinositides and HSP27 in regulating NRF2 and point to PIPKIg and HSP27 as drug targets to destabilize NRF2 in cancer. In brief: Phosphoinositides are coupled to NRF2 by PIPKIγ, and HSP27 is recruited and stabilizes NRF2, promoting stress-resistance.

10.
Biomolecules ; 13(10)2023 09 22.
Artigo em Inglês | MEDLINE | ID: mdl-37892112

RESUMO

The capacity for cancer cells to metastasize to distant organs depends on their ability to execute the carefully choreographed processes of cell adhesion and migration. As most human cancers are of epithelial origin (carcinoma), the transcriptional downregulation of adherent/tight junction proteins (e.g., E-cadherin, Claudin and Occludin) with the concomitant gain of adhesive and migratory phenotypes has been extensively studied. Most research and reviews on cell adhesion and migration focus on the actin cytoskeleton and its reorganization. However, metastasizing cancer cells undergo the extensive reorganization of their cytoskeletal system, specifically in originating/nucleation sites of microtubules and their orientation (e.g., from non-centrosomal to centrosomal microtubule organizing centers). The precise mechanisms by which the spatial and temporal reorganization of microtubules are linked functionally with the acquisition of an adhesive and migratory phenotype as epithelial cells reversibly transition into mesenchymal cells during metastasis remains poorly understood. In this Special Issue of "Molecular Mechanisms Underlying Cell Adhesion and Migration", we highlight cell adhesion and migration from the perspectives of microtubule cytoskeletal reorganization, cell polarity and phosphoinositide signaling.


Assuntos
Polaridade Celular , Fosfatidilinositóis , Humanos , Adesão Celular/fisiologia , Fosfatidilinositóis/metabolismo , Movimento Celular/fisiologia , Citoesqueleto/metabolismo , Microtúbulos/metabolismo
11.
Reprod Fertil ; 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37869895

RESUMO

In the context of a cancer diagnosis, fertility preservation interventions are used to mitigate the potential impact of gonadotoxic cancer treatment upon fertility. They provide patients with cancer the option to freeze their reproductive material to have their own biological child following treatment. The evidence suggests some clinicians are less likely to have fertility preservation discussions with patients who have an aggressive or metastatic cancer which has a poor prognosis. Although this is contrary to current policy recommendations, there is a lack of guidance relating to offering fertility preservation in the context of a poor prognosis to support clinicians. Controversy surrounds posthumous reproduction, and whether the wishes of the cancer patient, when living and deceased should take precedence over others' wellbeing. We consider the question of whether cancer patients with a poor prognosis should be offered FP from an ethics perspective. We structure the paper around key arguments to which multiple ethical principles might pertain, first establishing a central argument in favour of offering fertility preservation based on respect for autonomy, before exploring counterarguments. We conclude by proposing that a defeasible assumption should be adopted in favour of offering fertility preservation to all cancer patients who might benefit from it. It is important to recognise that patients could benefit from fertility preservation in many ways, and these are not limited to having a parenting experience. The burden of proof rests on the clinician in collaboration with their multi-disciplinary team, to show that there are good grounds for withholding the offer.

12.
Lancet Oncol ; 24(10): e415-e423, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37797647

RESUMO

Anticancer agents can impair ovarian function, resulting in premature menopause and associated long-term health effects. Ovarian toxicity is not usually adequately assessed in trials of anticancer agents, leaving an important information gap for patients facing therapy choices. This American Society of Clinical Oncology (ASCO) statement provides information about the incorporation of ovarian toxicity measures in trial design. ASCO recommends: (1) measurement of ovarian toxicity in relevant clinical trials of anticancer agents that enrol post-pubertal, pre-menopausal patients; (2) collection of ovarian function measures at baseline and at 12-24 months after anticancer agent cessation, as a minimum, and later in line with the trial schedule; and (3) assessment of both clinical measures and biomarkers of ovarian function. ASCO recognises that routine measurement of ovarian toxicity and function in cancer clinical trials will add additional complexity and burden to trial resources but asserts that this issue is of such importance to patients that it cannot continue to be overlooked.


Assuntos
Antineoplásicos , Neoplasias , Feminino , Humanos , Estados Unidos , Neoplasias/terapia , Antineoplásicos/efeitos adversos , Ovário , Oncologia
13.
Development ; 150(23)2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-37840454

RESUMO

The emergence of definitive human haematopoietic stem cells (HSCs) from Carnegie Stage (CS) 14 to CS17 in the aorta-gonad-mesonephros (AGM) region is a tightly regulated process. Previously, we conducted spatial transcriptomic analysis of the human AGM region at the end of this period (CS16/CS17) and identified secreted factors involved in HSC development. Here, we extend our analysis to investigate the progression of dorso-ventral polarised signalling around the dorsal aorta over the entire period of HSC emergence. Our results reveal a dramatic increase in ventral signalling complexity from the CS13-CS14 transition, coinciding with the first appearance of definitive HSCs. We further observe stage-specific changes in signalling up to CS17, which may underpin the step-wise maturation of HSCs described in the mouse model. The data-rich resource is also presented in an online interface enabling in silico analysis of molecular interactions between spatially defined domains of the AGM region. This resource will be of particular interest for researchers studying mechanisms underlying human HSC development as well as those developing in vitro methods for the generation of clinically relevant HSCs from pluripotent stem cells.


Assuntos
Células-Tronco Hematopoéticas , Transdução de Sinais , Camundongos , Animais , Humanos , Transdução de Sinais/genética , Comunicação Celular , Perfilação da Expressão Gênica , Aorta , Mesonefro , Gônadas , Hematopoese/genética
14.
Biomolecules ; 13(9)2023 08 24.
Artigo em Inglês | MEDLINE | ID: mdl-37759697

RESUMO

Cytoplasmic phosphoinositides (PI) are critical regulators of the membrane-cytosol interface that control a myriad of cellular functions despite their low abundance among phospholipids. The metabolic cycle that generates different PI species is crucial to their regulatory role, controlling membrane dynamics, vesicular trafficking, signal transduction, and other key cellular events. The synthesis of phosphatidylinositol (3,4,5)-triphosphate (PI3,4,5P3) in the cytoplamic PI3K/Akt pathway is central to the life and death of a cell. This review will focus on the emerging evidence that scaffold proteins regulate the PI3K/Akt pathway in distinct membrane structures in response to diverse stimuli, challenging the belief that the plasma membrane is the predominant site for PI3k/Akt signaling. In addition, we will discuss how PIs regulate the recruitment of specific scaffolding complexes to membrane structures to coordinate vesicle formation, fusion, and reformation during autophagy as well as a novel lysosome repair pathway.


Assuntos
Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Proteínas Proto-Oncogênicas c-akt/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Transdução de Sinais/fisiologia , Membrana Celular/metabolismo , Fosfatidilinositóis/metabolismo
15.
Front Endocrinol (Lausanne) ; 14: 1146476, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37404308

RESUMO

Background: Fertility preservation is an important healthcare focus in the paediatric and adolescent population when gonadotoxic treatments are required. Ovarian stimulation (OS) resulting in oocyte cryopreservation is a well-established fertility preservation option in the adult population. It's utility, however, is little known in young patients. The purpose of this review was to synthesise the available literature on OS in patients ≤18 years old, to identify gaps in current research and provide suggestions for future research directions. Methods: Using PRISMA guidelines, a systematic review of the literature was performed for all relevant full-text articles published in English in Medline, Embase, the Cochrane Library and Google Scholar databases. The search strategy used a combination of subject headings and generic terms related to the study topic and population. Two reviewers independently screened studies for eligibility, extracted data and assessed the risk of bias. Characteristics of the studies, objectives and key findings were extracted and summarised in a narrative synthesis. Results: Database search and manual review identified 922 studies, 899 were eliminated based on defined exclusion criteria. Twenty-three studies were included and comprised 468 participants aged ≤18 years who underwent OS (median 15.2, range 7-18 years old). Only three patients were premenarchal, and four patients were on treatment to suppress puberty. Patients had OS for a broad range of indications including oncology treatment, transgender care and Turner syndrome. A total of 488 cycles of OS were completed, with all but 18 of these cycles (96.3%) successfully resulting in cryopreserved mature oocytes (median 10 oocytes, range 0-35). Fifty-three cycles (9.8%) were cancelled. Complications were rare (<1%). One pregnancy was reported from a female who had OS aged 17 years old. Conclusion: This systematic review demonstrates that OS and oocyte cryopreservation is achievable in young females however there are only a few cases in the literature describing OS in premenarcheal children or those who have suppressed puberty. There is little proof that OS can lead to pregnancy in adolescents, and no proof that this can be achieved in premenarchal girls. Therefore it should be regarded as an innovative procedure for adolescents and experimental for premenarcheal girls. Systematic review registration: https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=265705, identifier CRD42021265705.


Assuntos
Pessoas Transgênero , Gravidez , Feminino , Masculino , Humanos , Maturidade Sexual , Criopreservação/métodos , Oócitos/fisiologia , Indução da Ovulação/métodos
16.
Pediatr Blood Cancer ; 70 Suppl 5: e28854, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37381152

RESUMO

In the survivorship setting, adolescent and young adult (AYA) cancer survivors frequently demonstrate little knowledge of infertility risk, are unclear regarding their fertility status, and may under- or overestimate their treatment-related risk for infertility. In female AYA survivors, ovarian function usually parallels fertility, and can be assessed with serum hormone levels and ultrasonography. Posttreatment fertility preservation may be appropriate for survivors at risk for primary ovarian insufficiency. In male AYA survivors, fertility and gonadal function are not always equally affected, and can be assessed with a semen analysis and serum hormones, respectively. As reproductive health issues are commonly cited as an important concern by survivors of AYA cancer, multidisciplinary care teams including oncology, endocrinology, psychology, and reproductive medicine are advocated, with the aim of optimal provision of fertility advice and care for AYA cancer survivors.


Assuntos
Sobreviventes de Câncer , Preservação da Fertilidade , Infertilidade , Neoplasias , Humanos , Masculino , Feminino , Adulto Jovem , Adolescente , Sobreviventes de Câncer/psicologia , Fertilidade , Sobreviventes/psicologia , Preservação da Fertilidade/psicologia , Neoplasias/complicações , Neoplasias/terapia , Neoplasias/psicologia
18.
Physiol Rev ; 103(4): 2623-2677, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37171807

RESUMO

Mammalian eggs (oocytes) are formed during fetal life and establish associations with somatic cells to form primordial follicles that create a store of germ cells (the primordial pool). The size of this pool is influenced by key events during the formation of germ cells and by factors that influence the subsequent activation of follicle growth. These regulatory pathways must ensure that the reserve of oocytes within primordial follicles in humans lasts for up to 50 years, yet only approximately 0.1% will ever be ovulated with the rest undergoing degeneration. This review outlines the mechanisms and regulatory pathways that govern the processes of oocyte and follicle formation and later growth, within the ovarian stroma, through to ovulation with particular reference to human oocytes/follicles. In addition, the effects of aging on female reproductive capacity through changes in oocyte number and quality are emphasized, with both the cellular mechanisms and clinical implications discussed. Finally, the details of current developments in culture systems that support all stages of follicle growth to generate mature oocytes in vitro and emerging prospects for making new oocytes from stem cells are outlined.


Assuntos
Oócitos , Folículo Ovariano , Animais , Humanos , Feminino , Oócitos/fisiologia , Folículo Ovariano/metabolismo , Ovário/metabolismo , Oogênese/fisiologia , Mamíferos/fisiologia , Envelhecimento
19.
bioRxiv ; 2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37214930

RESUMO

The membrane-localized phosphatidylinositol (PI) 3-kinase (PI3K)/Akt pathway regulates cell growth and is aberrantly activated in cancer. Recent studies reveal a distinct nuclear PI3K/Akt pathway involving PI phosphate (PIP) kinases that bind the tumor suppressor protein p53 (wild-type and mutant) to generate nuclear p53-polyphosphoinositide (PIP n ) complexes that activate Akt. In the membrane pathway, PI transfer proteins (PITPs) transport PI, the precursor of PIP n s, to endomembranes to enable PIP n synthesis. In contrast, nuclear PIP n signaling relies on poorly characterized non-membranous PIP n pools. Here we show that PITPs accumulate in the non-membranous nucleoplasm in response to stress and are necessary to generate nuclear PIP n pools. Class I PITPα/ß bind p53 to form p53-PIP n complexes that activate nuclear Akt in response to stress, which inhibits apoptosis. These findings demonstrate an unexpected function for PITPα/ß in nuclear PIP n signaling by generating membrane-free, protein-linked PIP n pools that are modified by PIP kinases/phosphatases to regulate protein function. In brief: Phosphatidylinositol transfer proteins initiate the nuclear protein-associated PIP n network in membrane-free regions.

20.
Front Endocrinol (Lausanne) ; 14: 1149473, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37223019

RESUMO

Background: Polycystic ovary syndrome (PCOS) is a heterogeneous disorder, affecting around 10% of women of reproductive age, with infertility, depression or anxiety, obesity, insulin resistance and type 2 diabetes as risk factors. The cause of PCOS is not known but there is a predisposition to developing PCOS in adult life that arises during fetal or perinatal life. PCOS also has a genetic predisposition and a number of genetic loci associated with PCOS have been identified. These loci contain 25 candidate genes which are currently being studied to define the syndrome. Although the name PCOS suggests a syndrome of the ovary, PCOS has also been associated with the central nervous system and other organ systems in the body due to the wide variety of symptoms it presents. Methods: Here, we examined the expression patterns of PCOS candidate genes in gonadal (ovary and testis), metabolic (heart, liver and kidney) and brain (brain and cerebellum) tissues during the first half of human fetal development and postnatally until adulthood using public RNA sequencing data. This study is an initial step for more comprehensive and translational studies to define PCOS. Results: We found that the genes were dynamically expressed in the fetal tissues studied. Some genes were significantly expressed in gonadal tissues, whilst others were expressed in metabolic or brain tissues at different time points prenatally and/or postnatally. HMGA2, FBN3 and TOX3 were highly expressed during the early stages of fetal development in all tissues but least during adulthood. Interestingly, correlation between expression of HMGA2/YAP1 and RAD50/YAP1 were significant in at least 5 of the 7 fetal tissues studied. Notably, DENND1A, THADA, MAPRE1, RAB5B, ARL14EP, KRR1, NEIL2 and RAD50 were dynamically expressed in all postnatal tissues studied. Conclusions: These findings suggest that these genes have tissue- or development-specific roles in multiple organs, possibly resulting in the various symptoms associated with PCOS. Thus the fetal origin of a predisposition to PCOS in adulthood could arise via the effects of PCOS candidate genes in the development of multiple organs.


Assuntos
Diabetes Mellitus Tipo 2 , Síndrome do Ovário Policístico , Adulto , Gravidez , Masculino , Humanos , Feminino , Síndrome do Ovário Policístico/genética , Gônadas , Feto , Encéfalo
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