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1.
Clin Cancer Res ; 29(14): 2602-2611, 2023 07 14.
Artigo em Inglês | MEDLINE | ID: mdl-36799931

RESUMO

PURPOSE: A single maintenance course of a PARP inhibitor (PARPi) improves progression-free survival (PFS) in germline BRCA1/2-mutant high-grade serous ovarian cancer (gBRCAm-HGSOC). The feasibility of a second maintenance course of PARPi was unknown. PATIENTS AND METHODS: Phase II trial with two entry points (EP1, EP2). Patients were recruited prior to rechallenge platinum. Patients with relapsed, gBRCAm-HGSOC were enrolled at EP1 if they were PARPi-naïve. Patients enrolled at EP2 had received their first course of olaparib prior to trial entry. EP1 patients were retreated with olaparib after RECIST complete/partial response (CR/PR) to platinum. EP2 patients were retreated with olaparib ± cediranib after RECIST CR/PR/stable disease to platinum and according to the platinum-free interval. Co-primary outcomes were the proportion of patients who received a second course of olaparib and the proportion who received olaparib retreatment for ≥6 months. Functional homologous recombination deficiency (HRD), somatic copy-number alteration (SCNA), and BRCAm reversions were investigated in tumor and liquid biopsies. RESULTS: Twenty-seven patients were treated (EP1 = 17, EP2 = 10), and 19 were evaluable. Twelve patients (63%) received a second course of olaparib and 4 received olaparib retreatment for ≥6 months. Common grade ≥2 adverse events during olaparib retreatment were anemia, nausea, and fatigue. No cases of MDS/AML occurred. Mean duration of olaparib treatment and retreatment differed (12.1 months vs. 4.4 months; P < 0.001). Functional HRD and SCNA did not predict PFS. A BRCA2 reversion mutation was detected in a post-olaparib liquid biopsy. CONCLUSIONS: A second course of olaparib can be safely administered to women with gBRCAm-HGSOC but is only modestly efficacious. See related commentary by Gonzalez-Ochoa and Oza, p. 2563.


Assuntos
Antineoplásicos , Cistadenocarcinoma Seroso , Neoplasias Ovarianas , Humanos , Feminino , Inibidores de Poli(ADP-Ribose) Polimerases/efeitos adversos , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/patologia , Carcinoma Epitelial do Ovário/tratamento farmacológico , Carcinoma Epitelial do Ovário/genética , Antineoplásicos/uso terapêutico , Ftalazinas/efeitos adversos , Cistadenocarcinoma Seroso/tratamento farmacológico , Cistadenocarcinoma Seroso/genética , Recidiva Local de Neoplasia/tratamento farmacológico , Recidiva Local de Neoplasia/genética , Recidiva Local de Neoplasia/mortalidade
2.
Cancers (Basel) ; 15(3)2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36765687

RESUMO

Women diagnosed with non-mucinous high-grade epithelial ovarian cancer (EOC) in England are often reflex-tested for germline and tumour BRCA1/2 variants. The value of germline BRCA1/2 testing in women diagnosed aged ≥80 is questionable. We performed an observational study of all women diagnosed with non-mucinous high-grade EOC who underwent germline and tumour BRCA1/2 testing by the North West of England Genomic Laboratory Hub. A subgroup of women also underwent germline testing using a panel of homologous recombination repair (HRR) genes and/or tumour testing for homologous recombination deficiency (HRD) using Myriad's myChoice® companion diagnostic. Seven-hundred-two patients successfully underwent both germline and tumour BRCA1/2 testing. Of these, 48 were diagnosed with non-mucinous high-grade EOC aged ≥80. In this age group, somatic BRCA1/2 pathogenic/likely pathogenic variants (PV/LPVs) were detected nine times more often than germline BRCA1/2 PV/LPVs. The only germline PV reported in a patient aged ≥80 was detected in germline and tumour DNA (BRCA2 c.4478_4481del). No patient aged ≥80 had a germline PV/LPVs in a non-BRCA1/2 HRR gene. Thirty-eight percent of patients aged ≥80 had a tumour positive for HRD. Our data suggest that tumour BRCA1/2 and HRD testing is adequate for patients diagnosed with non-mucinous high-grade EOC aged ≥80, with germline BRCA1/2 testing reserved for women with a tumour BRCA1/2 PV/LPVs.

3.
Cancers (Basel) ; 16(1)2023 Dec 29.
Artigo em Inglês | MEDLINE | ID: mdl-38201604

RESUMO

Patients diagnosed with epithelial ovarian cancer may undergo reflex tumour BRCA1/2 testing followed by germline BRCA1/2 testing in patients with a positive tumour test result. This testing model relies on tumour BRCA1/2 tests being able to detect all types of pathogenic variant. We analysed germline and tumour BRCA1/2 test results from patients treated for epithelial ovarian cancer at our specialist oncological referral centre. Tumour BRCA1/2 testing was performed using the next-generation sequencing (NGS)-based myChoice® companion diagnostic (CDx; Myriad Genetics, Inc.). Germline BRCA1/2 testing was performed in the North West Genomic Laboratory Hub using NGS and multiplex ligation-dependent probe amplification. Between 11 April 2021 and 11 October 2023, 382 patients were successfully tested for tumour BRCA1 and BRCA2 variants. Of these, 367 (96.1%) patients were tested for germline BRCA1/2 variants. In those patients who underwent tumour and germline testing, 15.3% (56/367) had a BRCA1/2 pathogenic variant (36 germline and 20 somatic). All germline BRCA1/2 pathogenic small sequencing variants were detected in tumour DNA. By contrast, 3 out of 8 germline BRCA1/2 pathogenic large rearrangements were not reported in tumour DNA. The overall concordance of germline BRCA1/2 pathogenic variants detected in germline and tumour DNA was clinically acceptable at 91.7% (33/36). The myChoice® CDx was able to detect most germline BRCA1/2 pathogenic variants in tumour DNA, although a proportion of pathogenic large rearrangements were not reported. If Myriad's myChoice® CDx is used for tumour BRCA1/2 testing, our data supports a testing strategy of germline and tumour BRCA1/2 testing in all patients diagnosed with epithelial ovarian cancer aged < 79 years old, with germline BRCA1/2 testing only necessary for patients aged ≥ 80 years old with a tumour BRCA1/2 pathogenic variant.

4.
Artigo em Inglês | MEDLINE | ID: mdl-36313956

RESUMO

This study introduces an ability-based method for personalized keyboard generation, wherein an individual's own movement and human-computer interaction data are used to automatically compute a personalized virtual keyboard layout. Our approach integrates a multidirectional point-select task to characterize cursor control over time, distance, and direction. The characterization is automatically employed to develop a computationally efficient keyboard layout that prioritizes each user's movement abilities through capturing directional constraints and preferences. We evaluated our approach in a study involving 16 participants using inertial sensing and facial electromyography as an access method, resulting in significantly increased communication rates using the personalized keyboard (52.0 bits/min) when compared to a generically optimized keyboard (47.9 bits/min). Our results demonstrate the ability to effectively characterize an individual's movement abilities to design a personalized keyboard for improved communication. This work underscores the importance of integrating a user's motor abilities when designing virtual interfaces.

5.
Vibration ; 5(4): 692-710, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36299552

RESUMO

Silent speech interfaces (SSIs) enable speech recognition and synthesis in the absence of an acoustic signal. Yet, the archetypal SSI fails to convey the expressive attributes of prosody such as pitch and loudness, leading to lexical ambiguities. The aim of this study was to determine the efficacy of using surface electromyography (sEMG) as an approach for predicting continuous acoustic estimates of prosody. Ten participants performed a series of vocal tasks including sustained vowels, phrases, and monologues while acoustic data was recorded simultaneously with sEMG activity from muscles of the face and neck. A battery of time-, frequency-, and cepstral-domain features extracted from the sEMG signals were used to train deep regression neural networks to predict fundamental frequency and intensity contours from the acoustic signals. We achieved an average accuracy of 0.01 ST and precision of 0.56 ST for the estimation of fundamental frequency, and an average accuracy of 0.21 dB SPL and precision of 3.25 dB SPL for the estimation of intensity. This work highlights the importance of using sEMG as an alternative means of detecting prosody and shows promise for improving SSIs in future development.

6.
Artigo em Inglês | MEDLINE | ID: mdl-36287777

RESUMO

This study presents the evaluation of ability-based methods extended to keyboard generation for alternative communication in people with dexterity impairments due to motor disabilities. Our approach characterizes user-specific cursor control abilities from a multidirectional point-select task to configure letters on a virtual keyboard based on estimated time, distance, and direction of movement. These methods were evaluated in three individuals with motor disabilities against a generically optimized keyboard and the ubiquitous QWERTY keyboard. We highlight key observations relating to the heterogeneity of the manifestation of motor disabilities, perceived importance of communication technology, and quantitative improvements in communication performance when characterizing an individual's movement abilities to design personalized AAC interfaces.

7.
Br J Cancer ; 127(1): 163-167, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35260807

RESUMO

National guidelines recommend testing all cases of non-mucinous epithelial ovarian cancer (NMEOC) for germline (blood) and somatic (tumour) BRCA1/2 pathogenic variants (PVs). We performed paired germline and somatic BRCA1/2 testing in consecutive cases of NMEOC (n = 388) to validate guidelines. Thirty-four somatic BRCA1/2 (sBRCA) PVs (9.7%) were detected in 350 cases with germline BRCA1/2 (gBRCA) wild-type. All sBRCA PVs were detected in non-familial cases. By analysing our regional germline BRCA1/2 database there were 92/1114 (8.3%) gBRCA PVs detected in non-familial cases (only 3% ≥70 years old) and 245/641 (38.2%) in familial cases. Germline non-familial cases were dominated by BRCA2 in older women (8/271 ≥ 70 years old, all BRCA2). The ratio of sBRCA-to-gBRCA was ≤1.0 in women aged <70 years old, compared to 5.2 in women aged ≥70 years old (P = 0.005). The likelihood of missed germline BRCA1/2 PVs (copy-number variants missed on most somatic assays) by testing only tumour DNA was 0.4% in women aged ≥70 years old. We recommend reflex tumour BRCA1/2 testing in all NMEOC cases, and that gBRCA testing is not required for women aged ≥70 years old with no identifiable tumour BRCA1/2 PV and/or family history of breast, ovarian, prostate and/or pancreatic cancer.


Assuntos
Mutação em Linhagem Germinativa , Neoplasias Ovarianas , Idoso , Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Epitelial do Ovário/genética , Feminino , Testes Genéticos , Células Germinativas , Humanos , Neoplasias Ovarianas/genética
8.
Eur J Hum Genet ; 28(11): 1541-1547, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32651552

RESUMO

Poly(ADP-ribose) polymerase (PARP) inhibitors improve survival in BRCA-mutant high-grade serous ovarian carcinoma. As a result, germline and somatic BRCA1/2 testing has become standard practice in women diagnosed with ovarian cancer. We outline changes in testing and detection rates of germline BRCA1/2 pathogenic variants (PVs) in cases of non-mucinous epithelial ovarian cancer diagnosed during three eras, spanning 12 years, within the North West of England, and compare the uptake of cascade testing in families identified by oncology-led mainstreaming versus regional genetics clinics. Eras included: Period 1 (20% risk threshold for testing): between January 2007 and May 2013; Period 2 (10% risk threshold for testing): between June 2013 and October 2017 and; Period 3 (mainstream testing): between November 2017 and November 2019. A total of 1081 women underwent germline BRCA1/2 testing between January 2007 and November 2019 and 222 (20.5%) were found to have a PV. The monthly testing rate increased by 3.3-fold and 2.5-fold between Periods 1-2 and Periods 2-3, respectively. A similar incidence of germline BRCA1/2 PVs were detected in Period 2 (17.2%) and Period 3 (18.5%). Uptake of cascade testing from first-degree relatives was significantly lower in those women undergoing mainstream testing compared with those tested in regional genetics clinics (31.6% versus 47.3%, P = 0.038). Mainstream testing allows timely detection of germline BRCA1/2 status to select patients for PARP inhibitors, but shortfalls in the uptake of cascade testing in first-degree relatives requires optimisation to broaden benefits within families.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Epitelial do Ovário/genética , Testes Genéticos/métodos , Neoplasias Ovarianas/genética , Adulto , Idoso , Carcinoma Epitelial do Ovário/diagnóstico , Inglaterra , Feminino , Testes Genéticos/normas , Testes Genéticos/estatística & dados numéricos , Mutação em Linhagem Germinativa , Humanos , Pessoa de Meia-Idade , Neoplasias Ovarianas/diagnóstico
9.
J Med Genet ; 56(5): 301-307, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30683677

RESUMO

INTRODUCTION: Poly(ADP-ribose) polymerase inhibitors significantly improve progression-free survival in platinum-sensitive high-grade serous and endometrioid ovarian carcinoma, with greatest benefits observed in women with a pathogenic BRCA1/2 variant. Consequently, the demand for germline BRCA1/2 testing in ovarian cancer has increased substantially, leading to the screening of unselected populations of patients. We aimed to determine the prevalence of pathogenic germline BRCA1/2 variants in women diagnosed with epithelial ovarian cancer, categorised according to the established risk factors for hereditary breast and ovarian cancer syndrome and the Manchester BRCA Score, to inform risk stratification. METHODS: A cohort of sequential epithelial ovarian cancer cases recruited between June 2013 and September 2018 underwent germline BRCA1/2 testing by next-generation sequencing and multiplex ligation-dependent probe amplification. RESULTS: Five hundred and fifty-seven patients were screened. Of these, 18% had inherited a pathogenic BRCA1/2 variant. The prevalence of pathogenic BRCA1/2 variants was >10% in women diagnosed with ovarian cancer earlier than 60 years of age (21%) and those diagnosed later than 60 years of age with a family history of breast and/or ovarian cancer (17%) or a medical history of breast cancer (34%). The prevalence of pathogenic BRCA1/2 variants was also >10% in women with a Manchester BRCA Score of ≥15 points (14%). DISCUSSION: Our study suggests that age at diagnosis, family history of breast and/or ovarian cancer, medical history of breast cancer or a Manchester BRCA Score of ≥15 points are associated with a >10% prevalence of germline pathogenic BRCA1/2 variants in epithelial ovarian cancer.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Carcinoma Epitelial do Ovário/epidemiologia , Carcinoma Epitelial do Ovário/genética , Mutação em Linhagem Germinativa , Neoplasias Ovarianas/epidemiologia , Neoplasias Ovarianas/genética , Adulto , Idoso , Biomarcadores Tumorais , Carcinoma Epitelial do Ovário/diagnóstico , Carcinoma Epitelial do Ovário/mortalidade , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Testes Genéticos , Humanos , Pessoa de Meia-Idade , Gradação de Tumores , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/mortalidade , Prevalência , Prognóstico , Fatores de Risco , Adulto Jovem
10.
S Afr Med J ; 103(12 Suppl 1): 970-3, 2013 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-24300640

RESUMO

BACKGROUND: Fanconi anaemia (FA) is an autosomal recessive, genetically heterogeneous disorder, characterised by interstrand crosslink-induced chromosome breaks, congenital abnormalities and predisposition to malignancies. It has a prevalence of about 1/40 000 in black South Africans (SAs). A founder mutation in the FANCG gene occurs in the homozygous state in 77.5% of southern African blacks. OBJECTIVE: To locate additional pathogenic mutations in the FANCG gene of black FA patients who were heterozygous for the founder mutation. Methods. Further mutation analysis of the FANCG gene was undertaken in 7 patients clinically suspected of having FA. The parents of two of the patients were tested for the presence of the founder mutation to determine true heterozygosity in the patients. To clarify whether or not previously unreported variants were pathogenic, 58 random black SA individuals were screened. RESULTS: Three novel single base pair deletions, resulting in frameshift mutations (c.247delA, c.179delT and c.899delT) were identified in 3/7 patients. A fourth patient was found to have a single base substitution resulting in a splice site mutation (c.1636+1G>A). The remaining three patients were not found to harbour any pathogenic mutations. Two non-pathogenic variants were also identified among the seven patients. CONCLUSION: The results of this small sample suggest that a second common mutation in the FANCG gene is unlikely in this population. However, FANCG sequencing should be performed on patients heterozygous for the common founder mutation to attempt to confirm their diagnosis.


Assuntos
População Negra , Proteína do Grupo de Complementação G da Anemia de Fanconi/genética , Anemia de Fanconi/genética , Análise Mutacional de DNA , Mutação da Fase de Leitura , Heterozigoto , Humanos , África do Sul
11.
Int J Gynecol Cancer ; 21(1): 58-65, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21178570

RESUMO

BACKGROUND: Platinum-resistant and refractory cancers of the ovary, fallopian tube, and peritoneum have a poor prognosis, yet in some cases, they can respond to multiple lines of chemotherapy. Uncertainty remains over optimal drug choice and when therapeutic focus should be switched from active therapy to supportive care. METHODS: A retrospective case note review was performed on 274 women treated for platinum-resistant/refractory ovarian, fallopian tube, or peritoneal carcinoma at the Christie Hospital between 2004 and 2008. Baseline data at onset of platinum resistance and outcomes from subsequent lines of therapy were recorded. RESULTS: A total of 689 lines of therapy were administered with a median overall survival from initiation of first-line therapy for platinum-resistant disease of 61 weeks. Twenty-eight percent of women commenced cytotoxic therapy in the last 3 months of life. Treatment efficacy declined rapidly with successive lines of therapy particularly if disease progression occurred during first-line therapy. Factors independently associated with worse overall survival at recognition of platinum resistance were performance status, presence of stage IV disease, elevated cancer antigen 125, and platinum-refractory disease. CONCLUSIONS: A significant proportion of women who were treated received therapy within the last few months of life with little clinical benefit. Disease progression on 2 consecutive lines of therapy should be used as a guide to discontinue cytotoxic treatment. A subset of patients with poor prognosis at the onset of platinum resistance, who may have little gain from anticancer treatment, can be identified.


Assuntos
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Neoplasias das Tubas Uterinas/tratamento farmacológico , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Peritoneais/tratamento farmacológico , Adulto , Idoso , Idoso de 80 Anos ou mais , Hidrocarbonetos Aromáticos com Pontes/administração & dosagem , Antígeno Ca-125/sangue , Carcinoma/mortalidade , Carcinoma/radioterapia , Carcinoma Epitelial do Ovário , Cisplatino/administração & dosagem , Citotoxinas/administração & dosagem , Desoxicitidina/administração & dosagem , Desoxicitidina/análogos & derivados , Intervalo Livre de Doença , Doxorrubicina/administração & dosagem , Doxorrubicina/análogos & derivados , Etoposídeo/administração & dosagem , Neoplasias das Tubas Uterinas/mortalidade , Neoplasias das Tubas Uterinas/radioterapia , Feminino , Humanos , Estimativa de Kaplan-Meier , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neoplasias Epiteliais e Glandulares/tratamento farmacológico , Neoplasias Epiteliais e Glandulares/mortalidade , Neoplasias Epiteliais e Glandulares/radioterapia , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/radioterapia , Paclitaxel/administração & dosagem , Neoplasias Peritoneais/mortalidade , Neoplasias Peritoneais/radioterapia , Platina/administração & dosagem , Polietilenoglicóis/administração & dosagem , Prognóstico , Modelos de Riscos Proporcionais , Estudos Retrospectivos , Análise de Sobrevida , Taxoides/administração & dosagem , Resultado do Tratamento , Gencitabina
12.
Cancer Chemother Pharmacol ; 68(3): 631-41, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21120480

RESUMO

BACKGROUND: Cediranib (RECENTIN™) is an oral, highly potent VEGF inhibitor. This study evaluated the effect of food on the pharmacokinetics of cediranib and compared the administration of continual cediranib via two dosing strategies using this as a platform to investigate pharmacodynamic imaging biomarkers. METHODS: Sixty patients were randomised to receive two single doses of cediranib in either fed/fasted or fasted/fed state (Part A). In continual dosage phase (Part B), patients were randomised to a fixed-dose or dose-escalation arm. Exploratory pharmacodynamic assessments were performed using DCE-MRI and CT enhancing fraction (EnF). RESULTS: In part A, plasma AUC and C (max) of cediranib were lower in the presence of food by a mean of 24 and 33%, respectively (94% CI: AUC, 12-34% and C (max), 20-43%), indicating food reduces cediranib plasma exposure. In part B, cediranib 30 mg/day appeared to be the most sustainable for chronic dosing. Continuous cediranib therapy was associated with sustained antivascular effects up to 16 weeks, with significant reductions in DCE-MRI parameters and CT EnF. CONCLUSIONS: It is recommended that cediranib be administered at least 1 h before or 2 h after food. Evidence of antitumour activity was observed, with significant sustained effects upon imaging vascular parameters.


Assuntos
Neoplasias/tratamento farmacológico , Quinazolinas/farmacocinética , Quinazolinas/uso terapêutico , Adulto , Idoso , Área Sob a Curva , Estudos Cross-Over , Relação Dose-Resposta a Droga , Eletrocardiografia/efeitos dos fármacos , Jejum/metabolismo , Feminino , Interações Alimento-Droga , Humanos , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Neoplasias/patologia , Quinazolinas/efeitos adversos , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Adulto Jovem
13.
Clin Cancer Res ; 15(21): 6674-82, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19861458

RESUMO

PURPOSE: Little is known concerning the onset, duration, and magnitude of direct therapeutic effects of anti-vascular endothelial growth factor (VEGF) therapies. Such knowledge would help guide the rational development of targeted therapeutics from bench to bedside and optimize use of imaging technologies that quantify tumor function in early-phase clinical trials. EXPERIMENTAL DESIGN: Preclinical studies were done using ex vivo microcomputed tomography and in vivo ultrasound imaging to characterize tumor vasculature in a human HM-7 colorectal xenograft model treated with the anti-VEGF antibody G6-31. Clinical evaluation was by quantitative magnetic resonance imaging in 10 patients with metastatic colorectal cancer treated with bevacizumab. RESULTS: Microcomputed tomography experiments showed reduction in perfused vessels within 24 to 48 h of G6-31 drug administration (P

Assuntos
Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Neoplasias Colorretais/irrigação sanguínea , Neoplasias Colorretais/tratamento farmacológico , Diagnóstico por Imagem , Fator A de Crescimento do Endotélio Vascular/imunologia , Adolescente , Animais , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais Humanizados , Bevacizumab , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Feminino , Humanos , Camundongos , Camundongos Nus , Neovascularização Patológica/tratamento farmacológico , Ensaios Antitumorais Modelo de Xenoenxerto
14.
Int J Radiat Oncol Biol Phys ; 75(4): 1209-15, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19327904

RESUMO

PURPOSE: There is considerable interest in developing non-invasive methods of mapping tumor hypoxia. Changes in tissue oxygen concentration produce proportional changes in the magnetic resonance imaging (MRI) longitudinal relaxation rate (R(1)). This technique has been used previously to evaluate oxygen delivery to healthy tissues and is distinct from blood oxygenation level-dependent (BOLD) imaging. Here we report application of this method to detect alteration in tumor oxygenation status. METHODS AND MATERIALS: Ten patients with advanced cancer of the abdomen and pelvis underwent serial measurement of tumor R(1) while breathing medical air (21% oxygen) followed by 100% oxygen (oxygen-enhanced MRI). Gadolinium-based dynamic contrast-enhanced MRI was then performed to compare the spatial distribution of perfusion with that of oxygen-induced DeltaR(1). RESULTS: DeltaR(1) showed significant increases of 0.021 to 0.058 s(-1) in eight patients with either locally recurrent tumor from cervical and hepatocellular carcinomas or metastases from ovarian and colorectal carcinomas. In general, there was congruency between perfusion and oxygen concentration. However, regional mismatch was observed in some tumor cores. Here, moderate gadolinium uptake (consistent with moderate perfusion) was associated with low area under the DeltaR(1) curve (consistent with minimal increase in oxygen concentration). CONCLUSIONS: These results provide evidence that oxygen-enhanced longitudinal relaxation can monitor changes in tumor oxygen concentration. The technique shows promise in identifying hypoxic regions within tumors and may enable spatial mapping of change in tumor oxygen concentration.


Assuntos
Neoplasias Abdominais/metabolismo , Hipóxia Celular/fisiologia , Imageamento por Ressonância Magnética/métodos , Oxigênio/metabolismo , Adenocarcinoma/metabolismo , Adulto , Idoso , Idoso de 80 Anos ou mais , Área Sob a Curva , Carcinoma Hepatocelular/metabolismo , Carcinoma de Células Escamosas/metabolismo , Meios de Contraste , Feminino , Gadolínio , Humanos , Neoplasias Hepáticas/metabolismo , Masculino , Pessoa de Meia-Idade , Omento , Neoplasias Ovarianas , Oxigênio/administração & dosagem , Neoplasias Pélvicas/metabolismo , Neoplasias Peritoneais/metabolismo
15.
Clin Cancer Res ; 13(20): 6130-5, 2007 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-17947478

RESUMO

PURPOSE: To define a simple radiologic biomarker of prognosis in patients with advanced epithelial ovarian carcinoma on first-line chemotherapy. EXPERIMENTAL DESIGN: Twenty-seven patients receiving platinum-based chemotherapy with >2 cm residual disease [International Federation of Gynecology and Obstetrics (FIGO) stages IIIC or IV] after surgery were identified. The proportion of enhancing tumor tissue--the enhancing fraction--was calculated on pre-chemotherapy computed tomography scans at four Hounsfield unit (HU) thresholds and assessed for correlation with CA125 response, Response Evaluation Criteria in Solid Tumors (RECIST) radiologic response, and time to progression. Discriminative power was assessed by leave-one-out discriminant analysis. RESULTS: Pre-chemotherapy residual tumor volume did not correlate with clinical outcome. Pre-chemotherapy enhancing fraction at all thresholds significantly correlated with CA125 response (P < 0.001, rho = 0.553 for 50 HU; P < 0.001, rho = 0.565 for 60 HU; P < 0.001, rho = 0.553 for 70 HU; P = 0.001, rho = 0.516 for 80 HU). Significant correlations were also shown for radiologic response at all thresholds. Enhancing fraction predicted CA125 response with 81.9% to 86.4% specificity and Response Evaluation Criteria in Solid Tumors response with 74.9% to 76.8% specificity at 95% sensitivity (dependent on threshold). Enhancing fraction correlated with time to progression at the 60 HU (P = 0.045, rho = 0.336) and 70 HU (P = 0.042; rho = 0.340) thresholds. CONCLUSION: Pre-chemotherapy enhancing fraction is a simple quantitative radiologic measure. Further evaluation in larger trials is required to confirm the potential of enhancing fraction as a predictive factor, particularly for patients who may benefit from the addition of antiangiogenic therapy.


Assuntos
Antineoplásicos/farmacologia , Biomarcadores Tumorais , Carcinoma/genética , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Inibidores da Angiogênese/farmacologia , Protocolos de Quimioterapia Combinada Antineoplásica/farmacologia , Reações Falso-Positivas , Feminino , Humanos , Pessoa de Meia-Idade , Modelos Biológicos , Prognóstico , Sensibilidade e Especificidade , Resultado do Tratamento
16.
Proc Natl Acad Sci U S A ; 100(12): 7045-50, 2003 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-12764225

RESUMO

The architectural transcription factor SRY (sex-determining region of the Y chromosome) plays a key role in sex determination as indicated by the fact that mutations in SRY are responsible for XY gonadal dysgenesis in humans. Although many SRY mutations reduce DNA-binding/bending activity, it is not clear how SRY mutations that do not affect interaction with DNA contribute to disease. The SRY high-mobility group domain harbors two nuclear localization signals (NLSs), and here we examine SRY from four XY females with missense mutations in these signals. In all cases, mutant SRY protein is partly localized to the cytoplasm, whereas wild-type SRY is strictly nuclear. Each NLS can independently direct nuclear transport of a carrier protein in vitro and in vivo, with mutations in either affecting the rate and extent of nuclear accumulation. The N-terminal NLS function is independent of the conventional NLS-binding importins (IMPs) and requires unidentified cytoplasmic transport factors, whereas the C-terminal NLS is recognized by IMPbeta. The SRY-R133W mutant shows reduced IMPbeta binding as a direct consequence of the sex-reversing C-terminal NLS mutation. Of the N-terminal NLS mutants examined, SRY-R62G unexpectedly shows a marked reduction in IMPbeta binding, whereas SRY-R75N and SRY-R76P show normal IMPbeta binding, suggesting defects in the IMP-independent pathway. We conclude that SRY normally requires the two distinct NLS-dependent nuclear import pathways to reach sufficient levels in the nucleus for sex determination. This study documents cases of human disease being explained, at a molecular level, by the impaired ability of a protein to accumulate in the nucleus.


Assuntos
Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Transtornos do Desenvolvimento Sexual , Disgenesia Gonadal 46 XY/genética , Disgenesia Gonadal 46 XY/metabolismo , Mutação de Sentido Incorreto , Proteínas Nucleares , Fatores de Transcrição , beta Carioferinas/metabolismo , Transporte Ativo do Núcleo Celular , Sequência de Aminoácidos , Sequência de Bases , Sítios de Ligação/genética , DNA/genética , DNA/metabolismo , Proteínas de Ligação a DNA/química , Feminino , Genes sry , Humanos , Masculino , Modelos Biológicos , Modelos Moleculares , Dados de Sequência Molecular , Sinais de Localização Nuclear/química , Sinais de Localização Nuclear/genética , Sinais de Localização Nuclear/metabolismo , Homologia de Sequência de Aminoácidos , Processos de Determinação Sexual , Proteína da Região Y Determinante do Sexo
17.
Mol Genet Metab ; 77(3): 217-25, 2002 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-12409269

RESUMO

Sex determining Region of the Y chromosome (SRY) is the Y-borne gene required for male sex determination. Many XY females with complete gonadal dysgenesis carry SRY mutations. We describe here the effects of eight clinically isolated point mutations on the DNA-binding and -bending functions of SRY. We found that the seven mutations in the HMG domain affected the protein's DNA-binding and -bending activities to varying degrees, although all cause complete gonadal dysgenesis. DNA binding was abolished by the R75N and L94P mutations, severely disrupted by the F67V mutation and reduced by the M64R (6-fold), R76P (4-fold), A113T (3-fold), and M78T (1.7-fold) mutations. Of these, variant M64R showed no DNA-bending activity, while M78T caused a mild reduction in DNA bending. The S18N mutation, a familial mutation that lies outside the HMG domain and caused partial gonadal dysgenesis in one patient, had minimal effect on DNA binding and bending. Analysis of the NMR solution structure of the SRY HMG domain bound to DNA suggests that mutations disrupt the protein's conformation (helicity, packing), or interactions at the DNA interface. The degree to which mutations causing complete gonadal dysgenesis affect the DNA-binding activity varies. We propose that there is a threshold level of SRY activity or expression required for testis determination, as we observe that familial mutations have the least effect on SRY activity.


Assuntos
Proteínas de Ligação a DNA/genética , Disgenesia Gonadal 46 XY/genética , Mutação de Sentido Incorreto , Proteínas Nucleares , Fatores de Transcrição , Sequência de Aminoácidos , DNA/metabolismo , Proteínas de Ligação a DNA/metabolismo , Feminino , Disgenesia Gonadal 46 XY/etiologia , Disgenesia Gonadal 46 XY/metabolismo , Humanos , Masculino , Dados de Sequência Molecular , Ligação Proteica/fisiologia , Processos de Determinação Sexual , Proteína da Região Y Determinante do Sexo
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