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1.
BMJ Open ; 14(3): e078926, 2024 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-38458809

RESUMO

INTRODUCTION: Glioblastoma (GBM) is the most common adult primary malignant brain tumour. The condition is incurable and, despite aggressive treatment at first presentation, almost all tumours recur after a median of 7 months. The aim of treatment at recurrence is to prolong survival and maintain health-related quality of life (HRQoL). Chemotherapy is typically employed for recurrent GBM, often using nitrosourea-based regimens. However, efficacy is limited, with reported median survivals between 5 and 9 months from recurrence. Although less commonly used in the UK, there is growing evidence that re-irradiation may produce survival outcomes at least similar to nitrosourea-based chemotherapy. However, there remains uncertainty as to the optimum approach and there is a paucity of available data, especially with regards to HRQoL. Brain Re-Irradiation Or Chemotherapy (BRIOChe) aims to assess re-irradiation, as an acceptable treatment option for recurrent IDH-wild-type GBM. METHODS AND ANALYSIS: BRIOChe is a phase II, multi-centre, open-label, randomised trial in patients with recurrent GBM. The trial uses Sargent's three-outcome design and will recruit approximately 55 participants from 10 to 15 UK radiotherapy sites, allocated (2:1) to receive re-irradiation (35 Gy in 10 daily fractions) or nitrosourea-based chemotherapy (up to six, 6-weekly cycles). The primary endpoint is overall survival rate for re-irradiation patients at 9 months. There will be no formal statistical comparison between treatment arms for the decision-making primary analysis. The chemotherapy arm will be used for calibration purposes, to collect concurrent data to aid interpretation of results. Secondary outcomes include HRQoL, dexamethasone requirement, anti-epileptic drug requirement, radiological response, treatment compliance, acute and late toxicities, progression-free survival. ETHICS AND DISSEMINATION: BRIOChe obtained ethical approval from Office for Research Ethics Committees Northern Ireland (reference no. 20/NI/0070). Final trial results will be published in peer-reviewed journals and adhere to the ICMJE guidelines. TRIAL REGISTRATION NUMBER: ISRCTN60524.


Assuntos
Glioblastoma , Reirradiação , Adulto , Humanos , Glioblastoma/tratamento farmacológico , Glioblastoma/radioterapia , Qualidade de Vida , Recidiva Local de Neoplasia/tratamento farmacológico , Encéfalo , Ensaios Clínicos Controlados Aleatórios como Assunto , Estudos Multicêntricos como Assunto , Ensaios Clínicos Fase II como Assunto
2.
Artigo em Inglês | MEDLINE | ID: mdl-38072326

RESUMO

PURPOSE: Tumor hypoxia is an adverse prognostic factor in head and neck squamous cell carcinoma (HNSCC). We assessed whether patients with hypoxic HNSCC benefited from the addition of nimorazole to definitive intensity modulated radiation therapy (IMRT). METHODS AND MATERIALS: NIMRAD was a phase 3, multicenter, placebo-controlled, double-anonymized trial of patients with HNSCC unsuitable for concurrent platinum chemotherapy or cetuximab with definitive IMRT (NCT01950689). Patients were randomized 1:1 to receive IMRT (65 Gy in 30 fractions over 6 weeks) plus nimorazole (1.2 g/m2 daily, before IMRT) or placebo. The primary endpoint was freedom from locoregional progression (FFLRP) in patients with hypoxic tumors, defined as greater than or equal to the median tumor hypoxia score of the first 50 patients analyzed (≥0.079), using a validated 26-gene signature. The planned sample size was 340 patients, allowing for signature generation in 85% and an assumed hazard ratio (HR) of 0.50 for nimorazole effectiveness in the hypoxic group and requiring 66 locoregional failures to have 80% power in a 2-tail log-rank test at the 5% significance level. RESULTS: Three hundred thirty-eight patients were randomized by 19 centers in the United Kingdom from May 2014 to May 2019, with a median follow-up of 3.1 years (95% CI, 2.9-3.4). Hypoxia scores were available for 286 (85%). The median patient age was 73 years (range, 44-88; IQR, 70-76). There were 36 (25.9%) locoregional failures in the hypoxic group, in which nimorazole + IMRT did not improve FFLRP (adjusted HR, 0.72; 95% CI, 0.36-1.44; P = .35) or overall survival (adjusted HR, 0.96; 95% CI, 0.53-1.72; P = .88) compared with placebo + IMRT. Similarly, nimorazole + IMRT did not improve FFLRP or overall survival in the whole population. In total (N = 338), 73% of patients allocated nimorazole adhered to the drug for ≥50% of IMRT fractions. Nimorazole + IMRT caused more acute nausea compared with placebo + IMRT (Common Terminology Criteria for Adverse Events version 4.0 G1+2: 56.6% vs 42.4%, G3: 10.1% vs 5.3%, respectively; P < .05). CONCLUSIONS: Addition of the hypoxia modifier nimorazole to IMRT for locally advanced HNSCC in older and less fit patients did not improve locoregional control or survival.

3.
Clin Transl Radiat Oncol ; 38: 147-154, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36452431

RESUMO

•There is a lack of prospective level I evidence for the use of PBT for most adult cancers including oropharyngeal squamous cell carcinoma (OPSCC).•TORPEdO is the UK's first PBT clinical trial and aims to determine the benefits of PBT for OPSCC.•Training and support has been provided before and during the trial to reduce variations of contouring and radiotherapy planning.•There is a strong translational component within TORPEdO. Imaging and physics data along with blood, tissue collection will inform future studies in refining patient selection for IMPT.

5.
Reprod Biol Endocrinol ; 6: 4, 2008 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-18230131

RESUMO

BACKGROUND: The hypogonadal (hpg) mouse is widely used as an animal model with which to investigate the endocrine regulation of spermatogenesis. Chronic treatment of these GnRH-deficient mice with estradiol is known to induce testicular maturation and restore qualitatively normal spermatogenesis. The aim of the current studies was to investigate whether these effects of estradiol are direct effects in the testis, or indirect actions via paradoxical stimulation of FSH secretion from the pituitary gland. METHODS: Initially, Western blot and immunohistochemistry were used to analyse tissues from hpg mice to identify potential sites of action of estradiol. In the main study, hpg mice were treated for 50 days with either an estradiol implant or daily injections of recombinant human FSH, or a combination of both, to determine whether estradiol would have an additive or synergistic effect with FSH on testis development, as assessed by histological analysis and stereological quantification of Leydig, Sertoli and germ cell proliferation. RESULTS: Western blot analysis revealed ERalpha immunoreactive bands of appropriate molecular weight in extracts of testis and pituitary glands from hpg mice, and immunohistochemical studies confirmed ERalpha in nuclei of anterior pituitary cells and Leydig and peritubular cells in hpg mice. Histological and morphometric analyses revealed that estradiol treatment alone was as effective as FSH in promoting Sertoli cell production and proliferation of the seminiferous epithelium, resulting in the production of elongating spermatids. Combined estradiol and FSH treatment did not produce a greater effect than either treatment alone, though an increased dose of FSH significantly increased seminiferous tubule volume and testis weight and increase Sertoli cell numbers further within the same time frame. In contrast, estradiol caused substantial increases in the wet weight of the seminal vesicles, whereas FSH was without effect on this tissue, and did not augment the actions of estradiol. CONCLUSION: As ERalpha receptor is abundantly expressed in the pituitary gland of hpg mice, and estradiol did not exert effects on testis development over and above those of FSH, we conclude that the action of estradiol on testis development in hpg mice is predominantly via the stimulation of pituitary FSH release.


Assuntos
Estradiol/farmacologia , Hormônio Foliculoestimulante/farmacologia , Hipogonadismo/fisiopatologia , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento , Animais , Western Blotting , Proliferação de Células/efeitos dos fármacos , Sinergismo Farmacológico , Receptor alfa de Estrogênio/metabolismo , Hormônio Foliculoestimulante/sangue , Humanos , Imuno-Histoquímica , Células Intersticiais do Testículo/metabolismo , Masculino , Camundongos , Tamanho do Órgão/efeitos dos fármacos , Hipófise/metabolismo , Adeno-Hipófise/metabolismo , Adeno-Hipófise/patologia , Proteínas Recombinantes/farmacologia , Glândulas Seminais/patologia , Epitélio Seminífero/metabolismo , Epitélio Seminífero/patologia , Células de Sertoli/metabolismo , Espermátides/patologia , Espermatogênese/efeitos dos fármacos , Testículo/metabolismo , Testículo/patologia
6.
Hum Fertil (Camb) ; 9(3): 127-35, 2006 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17008264

RESUMO

The hypogonadal (hpg) mouse is an excellent animal model in which to investigate the mechanism of action of estrogens on spermatogenesis because it has arrested reproductive development without the need for surgical, endocrine, pharmacological or immunological intervention. Hpg mice are hypogonadotrophic and fail to show normal postnatal testicular development due to the congenital inability to synthesize gonadotropin-releasing hormone in the hypothalamus. The hpg testis remains responsive to gonadotropins and androgens in that fertility can be induced by treatment with these hormones. Surprisingly, chronic treatment with low concentrations of estradiol alone induces qualitatively normal spermatogenesis. The induction of testicular development by estradiol in hpg mice is accompanied by a paradoxical increase in FSH production. The actions of estradiol in hpg mice appear to be via genomic estrogen receptors, as concurrent treatment with estrogen-receptor antagonist ICI182,780 completely blocks these pituitary and testis responses. Concurrent treatment with the androgen receptor antagonist bicalutamide does not affect the estradiol-induced increase in pituitary FSH content, but markedly attenuates the estradiol-induced increase in testicular weight. Western blot analyses and immunohistochemistry provide evidence for estrogen-receptor alpha and beta expression in both pituitary gland and testis of the hpg mouse. Estradiol may therefore exert direct actions within the testes and/or indirect neuroendocrine actions via the release of FSH or other hormones from the pituitary gland, but its actions are dependent upon the availability of low levels of androgen within the testis.


Assuntos
Estrogênios/fisiologia , Hipogonadismo , Modelos Animais , Espermatogênese/fisiologia , Animais , Estradiol/farmacologia , Hormônio Foliculoestimulante/biossíntese , Hormônio Foliculoestimulante/metabolismo , Humanos , Hipogonadismo/genética , Masculino , Camundongos , Camundongos Mutantes , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Receptores de Estrogênio/fisiologia , Células de Sertoli/fisiologia , Espermatogênese/efeitos dos fármacos , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento
7.
Reproduction ; 130(5): 643-54, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16264094

RESUMO

Testicular development is arrested in the hypogonadal (hpg) mouse due to a congenital deficiency of hypothalamic gonadotropin-releasing hormone synthesis. Previous studies have demonstrated that chronic treatment of these mice with estradiol induces testicular maturation and qualitatively normal spermatogenesis, but it is not known whether these are direct effects via estrogen receptors expressed in the testis, or indirect actions via the pituitary gland. The aim of the current studies was to determine whether the actions of estradiol require the presence of androgens. Sensitive assays revealed that chronic estradiol treatment produced time-dependent increases in pituitary FSH production but no increases in pituitary LH or testicular testosterone content could be detected. As a functional test of androgen dependence, hpg mice were treated for 70 days with estradiol plus Casodex (bicalutamide), an androgen receptor antagonist. Casodex treatment markedly attenuated both the estradiol-induced increase in testicular weight and the proliferation of the seminiferous epithelium, as revealed by morphometric analysis. However, it did not affect the estradiol-induced increase in pituitary FSH content, nor did it affect estradiol-induced increases in the weight of the seminal vesicles and epididymides. We conclude that increased FSH production is not sufficient to explain the increase in testicular development induced by estradiol in hpg mice; there is a requirement for functional androgen receptors for induction of testicular growth.


Assuntos
Androgênios/metabolismo , Estradiol/farmacologia , Hipogonadismo/metabolismo , Espermatogênese/efeitos dos fármacos , Testículo/metabolismo , Antagonistas de Androgênios/farmacologia , Anilidas/farmacologia , Animais , Estradiol/análogos & derivados , Feminino , Hormônio Foliculoestimulante/sangue , Fulvestranto , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Mutantes , Nitrilas , Hipófise/efeitos dos fármacos , Hipófise/metabolismo , Receptores Androgênicos/metabolismo , Epitélio Seminífero/efeitos dos fármacos , Epitélio Seminífero/crescimento & desenvolvimento , Epitélio Seminífero/metabolismo , Testículo/efeitos dos fármacos , Testículo/crescimento & desenvolvimento , Compostos de Tosil , Útero/efeitos dos fármacos
8.
Reprod Biol Endocrinol ; 3: 48, 2005 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-16176578

RESUMO

BACKGROUND: Testicular development is arrested in the hypogonadal (hpg) mouse due to a congenital deficiency in hypothalamic gonadotropin-releasing hormone (GnRH) synthesis. Chronic treatment of male hpg mice with estradiol induces FSH synthesis and secretion, and causes testicular maturation and qualitatively normal spermatogenesis. As estradiol negative feedback normally inhibits FSH production in the male, this study tested whether this paradoxical response to estradiol in the male hpg mouse might be due to inadequate masculinisation or incomplete defeminization in the neonatal period. Previous studies have demonstrated that treatment of hpg mice with testosterone propionate in the immediate neonatal period is necessary to allow full reproductive behaviors to be expressed following suitable endocrine stimulation at adult ages. METHODS: Hpg mice were treated with 100 mug testosterone propionate or vehicle on postnatal day 2. At 35 days of age, subgroups of these mice were treated with silastic implants containing estradiol or cholesterol. Reproductive behavior was scored in tests with steroid-primed female mice, then testicular development was assessed histologically, and measures of pituitary FSH content made at 85 days of age. RESULTS: The neonatal testosterone propionate treatment successfully defeminized female litter mates, as revealed by impaired vaginal opening and deficiencies in lordosis behavior, and it allowed appropriate male reproductive behavior to be expressed in a proportion of the hpg males when tested at an adult age. However, neonatal androgen supplementation did not block or even reduce the subsequent actions of estradiol in increasing pituitary FSH content, nor did it affect the ability of estradiol to induce qualitatively normal spermatogenesis. CONCLUSION: The ability of the hpg male to show a "female" neuroendocrine response to estradiol is not a result of inadequate androgenization during neonatal development, and thus the actions of estradiol revealed in this rodent model are not an artefact of incomplete sexual differentiation, but reflect a physiological role of estradiol occurring during a specific early temporal window of male reproductive development.


Assuntos
Androgênios/farmacologia , Estradiol/farmacologia , Hormônio Foliculoestimulante/biossíntese , Hipogonadismo/fisiopatologia , Espermatogênese/efeitos dos fármacos , Propionato de Testosterona/farmacologia , Animais , Animais Recém-Nascidos , Colesterol/farmacologia , Feminino , Masculino , Camundongos , Camundongos Endogâmicos C3H , Camundongos Mutantes , Tamanho do Órgão/efeitos dos fármacos , Comportamento Sexual Animal , Testículo/anatomia & histologia , Testículo/efeitos dos fármacos
9.
Cancer Cell ; 6(3): 229-40, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15380514

RESUMO

Medulloblastoma is the most common malignant pediatric brain tumor. Current treatment is associated with major long-term side effects; therefore, new nontoxic therapies, targeting specific molecular defects in this cancer, need to be developed. We use a mouse model of medulloblastoma to show that inhibition of the Sonic Hedgehog (Shh) pathway provides a novel therapy for medulloblastoma. A small molecule inhibitor of the Shh pathway, HhAntag, blocked the function of Smoothened in mice with medulloblastoma. This resulted in suppression of several genes highly expressed in medulloblastoma, inhibition of cell proliferation, increase in cell death and, at the highest dose, complete eradication of tumors. Long-term treatment with HhAntag prolonged medulloblastoma-free survival. These findings support the development of Shh antagonists for the treatment of medulloblastoma.


Assuntos
Neoplasias Encefálicas/metabolismo , Meduloblastoma/metabolismo , Transativadores/antagonistas & inibidores , Animais , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/patologia , Divisão Celular , Intervalo Livre de Doença , Relação Dose-Resposta a Droga , Proteínas Hedgehog , Fatores de Transcrição Kruppel-Like , Meduloblastoma/tratamento farmacológico , Meduloblastoma/patologia , Camundongos , Camundongos Transgênicos , Receptores Acoplados a Proteínas G/metabolismo , Transdução de Sinais , Receptor Smoothened , Fatores de Transcrição/metabolismo , Células Tumorais Cultivadas , Proteína GLI1 em Dedos de Zinco
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