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1.
Clin Endocrinol (Oxf) ; 98(4): 567-577, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36372988

RESUMEN

OBJECTIVE: Growth differentiation factor-9 (GDF9) and bone morphogenetic protein-15 (BMP15) are critical paracrine regulators of female fertility and are predominantly expressed by oocytes. However, it is unknown if serum concentrations reflect changes in ovarian function and/or reproductive endocrine disorders. This study aimed to determine if serum GDF9/BMP15 are associated with ovarian, pituitary, oestrogenic, androgenic and metabolic characteristics and the ovarian pathologies, polycystic ovarian morphology (PCOM) and polycystic ovary syndrome (PCOS). DESIGN: Women aged 21-45 years (n = 381) were included from a cross-sectional study at the National University Hospital, Singapore. PATIENTS: Participants were volunteers and patients with possible PCOS. MEASUREMENTS: Anthropometric measurements, transvaginal ultrasound scans and serum sampling were performed and a questionnairecompleted. Serum GDF9 and BMP15 concentrations were matched with menstrual cycle length, ovarian protein and steroid hormone production, pituitary hormone production and metabolic assessments in women with PCOM or PCOS and those with neither (control). RESULTS: Serum GDF9 and BMP15 were detectable in 40% and 41% of women, respectively and were positively correlated with each other (r = 0.08, p = 0.003). GDF9, but not BMP15, was positively correlated with ovarian volume (p = 0.02) and antral follicle count (AFC) (p = 0.004), but not with anti-Müllerian hormone (p = 0.05). However, serum GDF9 and BMP15 concentrations were not significantly different between control, PCOM and PCOS women, nor associated with androgenic or metabolic PCOS features. However, the relationship between GDF9 and AFC differed between control, PCOM and PCOS women (p = 0.02). CONCLUSIONS: Serum GDF9 and BMP15 concentrations somewhat reflect ovarian but not androgenic or metabolic characteristics of PCOS, with increased GDF9 reflecting high AFC as seen in PCOM/PCOS.


Asunto(s)
Síndrome del Ovario Poliquístico , Femenino , Humanos , Folículo Ovárico/patología , Estudios Transversales , Oocitos , Hormona Antimülleriana , Proteína Morfogenética Ósea 15/metabolismo , Factor 9 de Diferenciación de Crecimiento/metabolismo
2.
BMC Womens Health ; 21(1): 135, 2021 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-33794861

RESUMEN

BACKGROUND: A diagnosis of Polycystic Ovary Syndrome (PCOS) and its related phenotypic features including increased hair growth can affect a woman's social and emotional well-being. We aim to determine firstly, if excess body weight affects menstrual cycle length, excessive hair growth and other phenotypic features in healthy women without PCOS and secondly, whether having PCOS exacerbates the effects of high body mass index (BMI). METHODS: A prospective cross-sectional study involving healthy women (21-45 years) recruited at an annual health screen for hospital staff and volunteers from the university community, and PCOS cases referred to tertiary gynecological clinics in Singapore. To dissect the independent and/or combinatorial effects of PCOS and BMI on the phenotypic features, subjects were divided into four categories: non-PCOS (normal BMI), non-PCOS (high BMI), PCOS (normal BMI), and PCOS (high BMI). General linear modelling was performed to compare clinical, ovarian, hormonal and metabolic parameters across these four categories. RESULTS: Of 389 participants, 134 (34.4%) were classified as PCOS and the remaining 255 (65.6%), as the non-PCOS population. Overall 45.2% of women had high BMI (≥ 23). Compared to non-PCOS subjects, women with PCOS had a higher BMI (mean (SD): 25.14 ± 6.46 vs 23.08 ± 4.36, p < 0.001). Women with PCOS and high BMI had increased hair growth with modified Ferriman-Gallwey (mFG) scores that were 2.96-fold higher versus healthy-normal BMI women (mean difference; 1.85, 95% CI 0.80-2.90). Compared to healthy-high BMI women, PCOS women with high BMI had significantly higher mean differences in mFG scores (1.79, 95% CI 0.64-2.93). In PCOS women, having high BMI also significantly increased mFG scores by 1.85-fold (mean difference; 1.82. 95% CI 0.52-3.12). This effect was mirrored by the additive effect of BMI and PCOS on free androgen index. No independent effect of high BMI on rates of oligomenorrhoea, antral follicle count, ovarian volume or serum androgens were observed. CONCLUSIONS: We observed an additive effect of body weight to increase hair growth in women with PCOS. Maximum mFG scores were present in PCOS women with high BMI. Such increases in mFG score may affect the self-esteem of women with PCOS.


Asunto(s)
Síndrome del Ovario Poliquístico , Índice de Masa Corporal , Estudios Transversales , Femenino , Humanos , Síndrome del Ovario Poliquístico/complicaciones , Síndrome del Ovario Poliquístico/epidemiología , Estudios Prospectivos , Singapur/epidemiología
3.
Clin Endocrinol (Oxf) ; 89(2): 202-211, 2018 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29851127

RESUMEN

OBJECTIVES: Although the Rotterdam 2003 polycystic ovarian syndrome (PCOS) diagnostic criteria is widely used, the need to consider multiple variables makes it unwieldy in clinical practice. We propose a simplified PCOS criteria wherein diagnosis is made if two of the following three items were present: (i) oligomenorrhoea, (ii) anti-mullerian hormone (AMH) above threshold and/or (iii) hyperandrogenism defined as either testosterone above threshold and/or the presence of hirsutism. DESIGN SETTING AND PARTICIPANTS: This prospective cross-sectional study consists of healthy women (n = 157) recruited at an annual hospital health screen for staff and volunteers from the university community, and a patient cohort (n = 174) comprising women referred for suspected PCOS. MAIN OUTCOME MEASURES: We used the healthy cohort to establish threshold values for serum testosterone, antral follicle counts (AFC), ovarian volume (OV) and AMH. Women from the patient cohort, classified as PCOS by simplified PCOS criteria, AMH alone and Rotterdam 2003, were compared with respect to prevalence of oligomenorrhoea, hyperandrogenism and metabolic indices. RESULTS: In healthy women, testosterone ≥1.89 nmol/L, AFC ≥22 follicles and OV ≥8.44 mL, best predicted oligomenorrhoea and were used as threshold values for PCOS criteria. An AMH level ≥37.0 pmol/L best predicted polycystic ovarian morphology. AMH alone as a single biomarker demonstrated poor specificity (58.9%) for PCOS compared to Rotterdam 2003. In contrast, there was a 94% overlap in women selected as PCOS by the simplified PCOS criteria and Rotterdam 2003. The population characteristics of these two groups of PCOS women showed no significant mean differences in androgenic, ovarian, AMH and metabolic (BMI, HOMA-IR) variables. CONCLUSIONS: Our data recommend the simplified PCOS criteria with population-specific thresholds for diagnosis of PCOS. Its ability to replace ovarian ultrasound biometry with the highly correlated variable AMH, and use of testosterone as a single marker for hyperandrogenaemia alongside the key symptoms of oligomenorrhoea and hirsutism confers significant clinical potential for the diagnosis of PCOS.

4.
Carcinogenesis ; 36(7): 757-68, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25908644

RESUMEN

Persistent androgen receptor (AR) signaling is the key driving force behind progression and development of castration-resistant prostate cancer (CRPC). In many patients, AR COOH-terminal truncated splice variants (ARvs) play a critical role in contributing to the resistance against androgen depletion therapy. Unfortunately, clinically used antiandrogens like bicalutamide (BIC) and enzalutamide (MDV), which target the ligand binding domain, have failed to suppress these AR variants. Here, we report for the first time that a natural prenylflavonoid, icaritin (ICT), can co-target both persistent AR and ARvs. ICT was found to inhibit transcription of key AR-regulated genes, such as KLK3 [prostate-specific antigen (PSA)] and ARvs-regulated genes, such as UBE2C and induce apoptosis in AR-positive prostate cancer (PC) cells. Mechanistically, ICT promoted the degradation of both AR and ARvs by binding to arylhydrocarbon-receptor (AhR) to mediate ubiquitin-proteasomal degradation. Therefore, ICT impaired AR transactivation in PC cells. Knockdown of AhR gene restored AR stability and partially prevented ICT-induced growth suppression. In clinically relevant murine models orthotopically implanted with androgen-sensitive and CRPC cells, ICT was able to target AR and ARvs, to inhibit AR signaling and tumor growth with no apparent toxicity. Our results provide a mechanistic framework for the development of ICT, as a novel lead compound for AR-positive PC therapeutics, especially for those bearing AR splice variants.


Asunto(s)
Antineoplásicos/farmacología , Flavonoides/farmacología , Neoplasias de la Próstata/tratamiento farmacológico , Receptores Androgénicos/metabolismo , Receptores de Hidrocarburo de Aril/metabolismo , Animales , Apoptosis/efectos de los fármacos , Apoptosis/genética , Línea Celular Tumoral/efectos de los fármacos , Regulación Neoplásica de la Expresión Génica/efectos de los fármacos , Humanos , Calicreínas/genética , Calicreínas/metabolismo , Masculino , Ratones Endogámicos NOD , Terapia Molecular Dirigida , Antígeno Prostático Específico/genética , Antígeno Prostático Específico/metabolismo , Neoplasias de la Próstata/metabolismo , Neoplasias de la Próstata/patología , Estabilidad Proteica/efectos de los fármacos , Empalme del ARN , Receptores Androgénicos/genética , Receptores de Hidrocarburo de Aril/genética , Transducción de Señal/efectos de los fármacos , Ubiquitina/metabolismo , Enzimas Ubiquitina-Conjugadoras/genética , Enzimas Ubiquitina-Conjugadoras/metabolismo , Ensayos Antitumor por Modelo de Xenoinjerto
5.
Biochim Biophys Acta ; 1807(6): 735-45, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21453675

RESUMEN

Defective or inefficient apoptosis is an acquired hallmark of cancer cells. Thus, a thorough understanding of apoptotic signaling pathways and insights into apoptosis resistance mechanisms are imperative to unravel novel drug targets for the design of more effective and target selective therapeutic strategies. This review aims at providing an overview of the recent understanding of apoptotic signaling pathways, the main mechanisms by which cancer cells resist apoptotic insults, and discusses some recent attempts to target the mitochondrion for restoring efficient cell death signaling in cancer cells.


Asunto(s)
Antineoplásicos/uso terapéutico , Apoptosis/fisiología , Resistencia a Antineoplásicos/fisiología , Mitocondrias/fisiología , Neoplasias/tratamiento farmacológico , Animales , Apoptosis/genética , Resistencia a Antineoplásicos/genética , Humanos , Oncología Médica/tendencias , Mitocondrias/genética , Mitocondrias/metabolismo , Modelos Biológicos , Neoplasias/genética , Neoplasias/metabolismo , Investigación/tendencias
6.
Endocrinol Diabetes Metab ; 2(3): e00047, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-31294078

RESUMEN

OBJECTIVE: Firstly, to investigate whether polycystic ovary syndrome (PCOS) shows a continuum of severity with increasing number of phenotypic features comprising the Rotterdam criteria for PCOS and secondly, to explore relationships of these phenotypes to the circadian biomarkers, cortisol and melatonin. BACKGROUND: Studies characterizing the spectrum of PCOS subphenotypes give little emphasis to the distinction among women who manifest zero, one or two of the three phenotypic features comprising the Rotterdam criteria. The relationship of circadian biomarkers to PCOS phenotypes is unclear. DESIGN: Cross-sectional study of 321 participants from 2011 to 2016 conducted at the National University Hospital (NUH), Singapore. PARTICIPANTS: Participants included women who attended a health screen for NUH staff, volunteers from the university community, and women referred for possible PCOS from gynaecological clinics at NUH and KK Women's and Children's Hospital (Singapore). METHODS: All participants underwent a physical examination, ovarian ultrasound scan and follicular-phase blood testing, and completed a health and lifestyle questionnaire. RESULTS: A significant positive linear trend in all clinical and biochemical characteristics of PCOS with increasing number of phenotypic features comprising the Rotterdam criteria. We observed a similar trend in serum cortisol and melatonin, two biomarkers of the circadian rhythm. CONCLUSION: PCOS may not be an "all-or-none" condition, but rather a continuous spectrum. The positive relationship between number of PCOS criteria with melatonin and cortisol merits further investigation on the role of circadian biorhythms in the pathogenesis of PCOS.

7.
Cancer Res ; 71(1): 266-76, 2011 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-21071633

RESUMEN

The human telomerase reverse transcriptase (hTERT) is the catalytic subunit of the telomerase holoenzyme. Evidence is accumulating to link hTERT to activities other than telomere maintenance and immortalization. Here, we show that hTERT overexpression not only reduces the basal cellular reactive oxygen species (ROS) levels but also inhibits endogenous ROS production in response to stimuli that induce intracellular ROS generation. Conversely, siRNA-mediated gene silencing of hTERT potentiated the increase in cellular ROS levels following exposure to oxidative stress. This antioxidant effect of hTERT is mediated via a significant increase in the ratio of reduced to oxidized glutathione (GSH:GSSG) as well as efficient recovery of the oxidized peroxiredoxin to its nonoxidized form. Our data also provide evidence for mitochondrial localization of hTERT, and a significantly higher activity of cytochrome C oxidase, the rate-limiting enzyme in the mitochondrial electron transport chain, in hTERT overexpressing cells. To ascertain whether the improved mitochondrial function and antioxidant effect of hTERT could provide cancer cells with a survival advantage, the effect of oxidative stress on mitochondrial apoptosis was evaluated. Indeed, hTERT overexpressing cells inhibited cytosolic acidification, translocation of Bax, the drop in mitochondrial transmembrane potential, the release of cytochrome C to the cytosol, and cell death. Taken together, these data demonstrate a hitherto undefined role of hTERT in alleviating cellular ROS levels by way of potentiating the cellular antioxidant defense systems, and in doing so endowing cancer cells with the ability to evade death stimuli.


Asunto(s)
Apoptosis/genética , Neoplasias/patología , Especies Reactivas de Oxígeno/metabolismo , Telomerasa/genética , Complejo IV de Transporte de Electrones/metabolismo , Citometría de Flujo , Disulfuro de Glutatión/metabolismo , Glutatión Peroxidasa/metabolismo , Glutatión Reductasa/metabolismo , Células HeLa , Humanos , Neoplasias/metabolismo , Oxidación-Reducción
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