6 research outputs found

    Upregulation of MAPK pathway is associated with survival in castrate-resistant prostate cancer

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    BACKGROUND: Recent evidence has implicated the MAP kinase (MAPK) pathway with the development of castrate-resistant prostate cancer (CRPC). We have previously reported gene amplification of critical members of this pathway with the development of castrate-resistant disease. In addition, we have shown that rising Raf-1 expression, with the development of CRPC, influences time to biochemical relapse. We therefore sought to further analyse the role of both Raf-1 and its downstream target MAPK in the molecular pathogenesis of CRPC. METHODS: Protein expression of Raf-1 and MAPK, including their activation status, was analysed using immunohistochemistry in a database of 65 paired tumour specimens obtained before and after the development of CRPC and correlated with other members of the pathway. RESULTS: Patients whose nuclear expression of MAPK rose with the development of CRPC had a significantly shorter median time to death following biochemical relapse (1.40 vs 3.00 years, P=0.0255) as well as reduced disease-specific survival when compared with those whose expression fell or remained unchanged (1.16 vs 2.62 years, P=0.0005). Significant correlations were observed between protein expression of Raf-1 and MAPK with the type 1 receptor tyrosine kinases, Her2 and epidermal growth factor receptor, as well as the transcription factor AP-1 in CRPC tumours. CONCLUSION: We conclude that the Her2/Raf-1/MAPK/AP-1 axis may promote the development of CRPC, leading to early relapse, and reduced disease-specific survival. In addition, members of the pathway may act as novel therapeutic and/or diagnostic targets for prostate cancer. British Journal of Cancer (2011) 104, 1920-1928. doi:10.1038/bjc.2011.163 www.bjcancer.com Published online 10 May 2011 (C) 2011 Cancer Research U

    Twin Town in South Brazil: A Nazi's Experiment or a Genetic Founder Effect?

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    Cândido Godói (CG) is a small municipality in South Brazil with approximately 6,000 inhabitants. It is known as the “Twins' Town” due to its high rate of twin births. Recently it was claimed that such high frequency of twinning would be connected to experiments performed by the German Nazi doctor Joseph Mengele. It is known, however, that this town was founded by a small number of families and therefore a genetic founder effect may represent an alternatively explanation for the high twinning prevalence in CG. In this study, we tested specific predictions of the “Nazi's experiment” and of the “founder effect” hypotheses. We surveyed a total of 6,262 baptism records from 1959–2008 in CG catholic churches, and identified 91 twin pairs and one triplet. Contrary to the “Nazi's experiment hypothesis”, there is no spurt in twinning between the years (1964–1968) when Mengele allegedly was in CG (P = 0.482). Moreover, there is no temporal trend for a declining rate of twinning since the 1960s (P = 0.351), and no difference in twinning among CG districts considering two different periods: 1927–1958 and 1959–2008 (P = 0.638). On the other hand, the “founder effect hypothesis” is supported by an isonymy analysis that shows that women who gave birth to twins have a higher inbreeding coefficient when compared to women who never had twins (0.0148, 0.0081, respectively, P = 0.019). In summary, our results show no evidence for the “Nazi's experiment hypothesis” and strongly suggest that the “founder effect hypothesis” is a much more likely alternative for explaining the high prevalence of twinning in CG. If this hypothesis is correct, then this community represents a valuable population where genetic factors linked to twinning may be identified

    Biological versus chronological ovarian age:implications for assisted reproductive technology

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    <p>Abstract</p> <p>Background</p> <p>Women have been able to delay childbearing since effective contraception became available in the 1960s. However, fertility decreases with increasing maternal age. A slow but steady decrease in fertility is observed in women aged between 30 and 35 years, which is followed by an accelerated decline among women aged over 35 years. A combination of delayed childbearing and reduced fecundity with increasing age has resulted in an increased number and proportion of women of greater than or equal to 35 years of age seeking assisted reproductive technology (ART) treatment.</p> <p>Methods</p> <p>Literature searches supplemented with the authors' knowledge.</p> <p>Results</p> <p>Despite major advances in medical technology, there is currently no ART treatment strategy that can fully compensate for the natural decline in fertility with increasing female age. Although chronological age is the most important predictor of ovarian response to follicle-stimulating hormone, the rate of reproductive ageing and ovarian sensitivity to gonadotrophins varies considerably among individuals. Both environmental and genetic factors contribute to depletion of the ovarian oocyte pool and reduction in oocyte quality. Thus, biological and chronological ovarian age are not always equivalent. Furthermore, biological age is more important than chronological age in predicting the outcome of ART. As older patients present increasingly for ART treatment, it will become more important to critically assess prognosis, counsel appropriately and optimize treatment strategies. Several genetic markers and biomarkers (such as anti-Müllerian hormone and the antral follicle count) are emerging that can identify women with accelerated biological ovarian ageing. Potential strategies for improving ovarian response include the use of luteinizing hormone (LH) and growth hormone (GH). When endogenous LH levels are heavily suppressed by gonadotrophin-releasing hormone analogues, LH supplementation may help to optimize treatment outcomes for women with biologically older ovaries. Exogenous GH may improve oocyte development and counteract the age-related decline of oocyte quality. The effects of GH may be mediated by insulin-like growth factor-I, which works synergistically with follicle-stimulating hormone on granulosa and theca cells.</p> <p>Conclusion</p> <p>Patients with biologically older ovaries may benefit from a tailored approach based on individual patient characteristics. Among the most promising adjuvant therapies for improving ART outcomes in women of advanced reproductive age are the administration of exogenous LH or GH.</p

    Recombinant LH supplementation to a standard GnRH antagonist protocol in women of 35 years or older undergoing IVF/ICSI: a randomized controlled multicentre study

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    Study question: Does the addition of exogenous LH to an IVF/ICSI stimulation protocol with recombinant FSH (r-FSH) and a GnRH antagonist improve the ovarian response and pregnancy rates in women of 35 years and older? Summary answer: Supplementation of LH during the second half of the follicular phase has no effect on pregnancy rates, implantation rates or on ovarian response in women of 35 years and older undergoing GnRH antagonist IVF/ICSI cycles. What is known already: In IVF/ICSI stimulation protocols GnRH agonists or antagonists are administered to prevent a premature pituitary LH surge, which can have a detrimental effect on the IVF/ICSI procedure. In effect, GnRH analogues cause the levels of both gonadotrophins to drop. In order to allow follicle growth FSH is administered exogenously, whereas LH is usually not supplemented. Although GnRH analogues prevent LH surges, there is evidence that, particularly in older women, administration of GnRH analogues may cause endogenous LH levels to decrease excessively. Several studies have been performed to investigate whether the addition of recombinant LH (r-LH) to r-FSH improves cycle outcome. Only a fewstudies have analysed this issue in theGnRHantagonist protocol and the results of these trials obtained in older women (.35 years old) are conflicting. Study design, size, duration: AmulticentreRCTwas performed between 2004 and 2010 in 253 couples whowere undergoing IVF or ICSI.Women were 35 years or older and received ovarian stimulation in a protocol with r-FSH (Gonal-F 225 IU/day) starting from cycle day 3 and GnRH antagonist (Cetrotide 0.25 mg/day) from stimulation day 6. Randomization took place on stimulation day 6 to receive both r-FSH and r-LH (Luveris 150 IU/day) or continue with FSH alone. Randomization for r-LH supplementation was performed centrally by serially numbered, opaque, sealed envelopes, stratified by centre. Participants/materials, setting, methods: Of 253 subjects randomized, 125 received both r-FSH and r-LH and 128 received r-FSH only. Patients were recruited from the Division of Reproductive Medicine of the Obstetrics and Gynaecology department of four hospitals in the Netherlands. Main results and the role of chance: Therewere no demographic or clinical differences between the groups. The intentionto-treat analysis revealed that of those receiving both r-FSH and r-LH, 35 (28.0%) had a clinical pregnancy, compared with 38 (29.7%) receiving only r-FSH (mean difference 21.5%; 95% confidence interval (CI) 29.4 to 12.7, P ¼ 0.9). Ongoing pregnancy rates were 25 (20%) versus 28 (21.9%) (mean difference 21.9%; 95% CI 28.2 to 11.9, P ¼ 0.9) and implantation rates 18.8 versus 20.7% (mean difference 21.9%; 95% CI 28.0 to 11.7, P ¼ 0.6) in the ‘r-FSH and r-LH’ and ‘r-FSH only’ groups respectively. Limitations, reasons for caution: A limitation of our study is its early closure. This was done because the interim analysis after randomization of 250 patients indicated no benefit in any aspect of the experiment. Wider implications of the findings: Given previous data, including a Cochrane review, and our own results the evidence indicates that LH supplementation has no benefit on ongoing pregnancy rates in women of 35 years or older. Study funding/competing interest(s): Merck Serono Netherlands, an affiliate of Merck Serono SA- Geneva, an affiliate of Merck KGaA, Darmstadt, Germany has donated the r-LH (Luverisw). No conflict of interest to declare
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