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1.
J Neurosci ; 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33785642

RESUMO

Sleep spindles are intermittent bursts of 11-15 Hz electroencephalogram (EEG) waves that occur during non-rapid eye movement (NREM) sleep. Spindles are believed to help maintain sleep and to play a role in sleep dependent memory consolidation. Here we applied an automated sleep spindle detection program to our large longitudinal sleep EEG dataset (98 human subjects, 6-18 y, >2000 uninterrupted nights) to evaluate maturational trends in spindle wave frequency, density, amplitude, and duration. This large dataset enabled us to apply non-linear as well as linear age models, thereby extending the findings of prior cross-sectional studies that used linear models. We found that spindle wave frequency increased with remarkable linearity across the age range. Central spindle density increased nonlinearly to a peak at age 15.1 years. Central spindle wave amplitude declined in a sigmoidal pattern with the age of fastest decline at 13.5 years. Spindle duration decreased linearly with age. Of the four measures, only spindle amplitude showed a sex difference in dynamics such that the age of most rapid decline in females preceded that in males by 1.4 years. This amplitude pattern, including the sex difference in timing, paralleled the maturational pattern for delta wave power. We interpret these age-related changes in spindle characteristics as indicators of maturation of thalamocortical circuits and changes in sleep depth. These robust age-effects could facilitate the search for cognitive-behavioral correlates of spindle waveforms and might also help guide basic research on EEG mechanisms and post-natal brain maturation.SIGNIFICANCE STATEMENT:The brain reorganization of adolescence produces massive changes in sleep electrophysiology (EEG). These changes include the morphology and abundance of sleep spindles, an EEG marker of NREM sleep believed to reflect offline memory processes and/or protection of the sleep state. We analyzed over 2000 nights of longitudinal sleep EEG from 98 subjects, age 6-18 y, to investigate maturational changes in spindle amplitude, frequency, density, and duration. The large dataset enabled us to detect non-linear as well as linear age changes. All measures showed robust age effects that we hypothesize reflect the maturation of thalamocortical circuits and decreasing sleep depth. These findings could guide further research into the cognitive-behavioral correlates of sleep spindles and their underlying brain mechanisms.

2.
Artigo em Inglês | MEDLINE | ID: mdl-33755789

RESUMO

PURPOSE: Irinotecan (IR) displays significant PK/PD variability. This study evaluated functional hepatic imaging (HNI) and extensive pharmacogenomics (PGs) to explore associations with IR PK and PD (toxicity and response). METHODS: Eligible patients (pts) suitable for Irinotecan-based therapy. At baseline: (i) PGs: blood analyzed by the Affymetrix-DMET™-Plus-Array (1936 variants: 1931 single nucleotide polymorphisms [SNPs] and 5 copy number variants in 225 genes, including 47 phase I, 80 phase II enzymes, and membrane transporters) and Sanger sequencing (variants in HNF1A, Topo-1, XRCC1, PARP1, TDP, CDC45L, NKFB1, and MTHFR), (ii) HNI: pts given IV 250 MBq-99mTc-IDA, data derived for hepatic extraction/excretion parameters (CLHNI, T1/2-HNI, 1hRET, HEF, Td1/2). In cycle 1, blood was taken for IR analysis and PK parameters were derived by non-compartmental methods. Associations were evaluated between HNI and PGs, with IR PK, toxicity, objective response rate (ORR) and progression-free survival (PFS). RESULTS: N = 31 pts. The two most significant associations between PK and PD with gene variants or HNI parameters (P < 0.05) included: (1) PK: SN38-Metabolic Ratio with CLHNI, 1hRET, (2) Grade 3+ diarrhea with SLC22A2 (rs 316019), GSTM5 (rs 1296954), (3) Grade 3+ neutropenia with CLHNI, 1hRET, SLC22A2 (rs 316019), CYP4F2 (rs2074900) (4) ORR with ALDH2 (rs 886205), MTHFR (rs 1801133). (5) PFS with T1/2-HNI, XDH (rs 207440), and ABCB11 (rs 4148777). CONCLUSIONS: Exploratory associations were observed between Irinotecan PK/PD with hepatic functional imaging and extensive pharmacogenomics. Further work is required to confirm and validate these findings in a larger cohort of patients. AUSTRALIAN NEW ZEALAND CLINICAL TRIALS REGISTRY (ANZCTR) NUMBER: ACTRN12610000897066, Date registered: 21/10/2010.

3.
Sleep ; 2021 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-33507305

RESUMO

STUDY OBJECTIVES: This report describes findings from an ongoing longitudinal study of the effects of varied sleep durations on wake and sleep electroencephalogram (EEG) and daytime function in adolescents. Here, we focus on the effects of age and time in bed (TIB) on total sleep time (TST) and nonrapid eye movement (NREM) and rapid eye movement (REM) EEG. METHODS: We studied 77 participants (41 male) ranging in age from 9.9 to 16.2 years over the 3 years of this study. Each year, participants adhered to each of three different sleep schedules: four consecutive nights of 7, 8.5, or 10 h TIB. RESULTS: Altering TIB successfully modified TST, which averaged 406, 472 and 530 min on the fourth night of 7, 8.5, and 10 h TIB, respectively. As predicted by homeostatic models, shorter sleep durations produced higher delta power in both NREM and REM although these effects were small. Restricted sleep more substantially reduced alpha power in both NREM and REM sleep. In NREM but not REM sleep, sleep restriction strongly reduced both the all-night accumulation of sigma EEG activity (11-15 Hz energy) and the rate of sigma production (11-15 Hz power). CONCLUSIONS: The EEG changes in response to TIB reduction are evidence of insufficient sleep recovery. The decrease in sigma activity presumably reflects depressed sleep spindle activity and suggests a manner by which sleep restriction reduces waking cognitive function in adolescents. Our results thus far demonstrate that relatively modest TIB manipulations provide a useful tool for investigating adolescent sleep biology.

4.
Histopathology ; 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33151585

RESUMO

Recently, genetic analyses of primary mucinous ovarian tumours (MOT) have considerably enhanced our understanding of the biology of such neoplasms, supporting a progressive model of carcinogenesis from benign/borderline tumours to carcinomas. Nevertheless, the histogenesis of these neoplasms remains a subject of discussion and several cell types of origin have been proposed; a proportion of these tumours are associated with Brenner (transitional cell) tumours, therefore some are believed to be derived from metaplastic mucinous epithelium lining cystic transitional cell nests (Walthard rests).

5.
J Pathol ; 2020 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-32901952

RESUMO

Low-grade serous ovarian carcinoma (LGSOC) is associated with a poor response to existing chemotherapy, highlighting the need to perform comprehensive genomic analysis and identify new therapeutic vulnerabilities. The data presented here represent the largest genetic study of LGSOCs to date (n = 71), analysing 127 candidate genes derived from whole exome sequencing cohorts to generate mutation and copy-number variation data. Additionally, immunohistochemistry was performed on our LGSOC cohort assessing oestrogen receptor, progesterone receptor, TP53, and CDKN2A status. Targeted sequencing identified 47% of cases with mutations in key RAS/RAF pathway genes (KRAS, BRAF, and NRAS), as well as mutations in putative novel driver genes including USP9X (27%), MACF1 (11%), ARID1A (9%), NF2 (4%), DOT1L (6%), and ASH1L (4%). Immunohistochemistry evaluation revealed frequent oestrogen/progesterone receptor positivity (85%), along with CDKN2A protein loss (10%) and CDKN2A protein overexpression (6%), which were linked to shorter disease outcomes. Indeed, 90% of LGSOC samples harboured at least one potentially actionable alteration, which in 19/71 (27%) cases were predictive of clinical benefit from a standard treatment, either in another cancer's indication or in LGSOC specifically. In addition, we validated ubiquitin-specific protease 9X (USP9X), which is a chromosome X-linked substrate-specific deubiquitinase and tumour suppressor, as a relevant therapeutic target for LGSOC. Our comprehensive genomic study highlighted that there is an addiction to a limited number of unique 'driver' aberrations that could be translated into improved therapeutic paths. © 2020 The Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

6.
NPJ Breast Cancer ; 6: 34, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32802943

RESUMO

Mammographic density (MD) influences breast cancer risk, but how this is mediated is unknown. Molecular differences between breast cancers arising in the context of the lowest and highest quintiles of mammographic density may identify the mechanism through which MD drives breast cancer development. Women diagnosed with invasive or in situ breast cancer where MD measurement was also available (n = 842) were identified from the Lifepool cohort of >54,000 women participating in population-based mammographic screening. This group included 142 carcinomas in the lowest quintile of MD and 119 carcinomas in the highest quintile. Clinico-pathological and family history information were recorded. Tumor DNA was collected where available (n = 56) and sequenced for breast cancer predisposition and driver gene mutations, including copy number alterations. Compared to carcinomas from low-MD breasts, those from high-MD breasts were significantly associated with a younger age at diagnosis and features associated with poor prognosis. Low- and high-MD carcinomas matched for grade, histological subtype, and hormone receptor status were compared for somatic genetic features. Low-MD carcinomas had a significantly increased frequency of TP53 mutations, higher homologous recombination deficiency, higher fraction of the genome altered, and more copy number gains on chromosome 1q and losses on 17p. While high-MD carcinomas showed enrichment of tumor-infiltrating lymphocytes in the stroma. The data demonstrate that when tumors were matched for confounding clinico-pathological features, a proportion in the lowest quintile of MD appear biologically distinct, reflective of microenvironment differences between the lowest and highest quintiles of MD.

7.
BMC Res Notes ; 13(1): 349, 2020 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-32698852

RESUMO

OBJECTIVE: Ovarian fibromas and adenofibromas are rare ovarian tumours. They are benign tumours composed of spindle-like stromal cells (pure fibroma) or a mixture of fibroblast and epithelial components (adenofibroma). We have previously shown that 40% of benign serous ovarian tumours are likely primary fibromas due to the neoplastic alterations being restricted to the stromal compartment of these tumours. We further explore this finding by comparing benign serous tumours to pure fibromas. RESULTS: Performing copy number aberration (CNA) analysis on the stromal component of 45 benign serous tumours and 8 pure fibromas, we have again shown that trisomy of chromosome 12 is the most common aberration in ovarian fibromas. CNAs were more frequent in the pure fibromas than the benign serous tumours (88% vs 33%), however pure fibromas more frequently harboured more than one CNA event compared with benign serous tumours. As these extra CNA events observed in the pure fibromas were unique to this subset our data indicates a unique tumour evolution. Gene expression analysis on the two cohorts was unable to show gene expression changes that differed based on tumour subtype. Exome analysis did not reveal any recurrently mutated genes.

8.
J Med Genet ; 2020 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-32546565

RESUMO

PURPOSE: The known epithelial ovarian cancer (EOC) susceptibility genes account for less than 50% of the heritable risk of ovarian cancer suggesting that other susceptibility genes exist. The aim of this study was to evaluate the contribution to ovarian cancer susceptibility of rare deleterious germline variants in a set of candidate genes. METHODS: We sequenced the coding region of 54 candidate genes in 6385 invasive EOC cases and 6115 controls of broad European ancestry. Genes with an increased frequency of putative deleterious variants in cases versus controls were further examined in an independent set of 14 135 EOC cases and 28 655 controls from the Ovarian Cancer Association Consortium and the UK Biobank. For each gene, we estimated the EOC risks and evaluated associations between germline variant status and clinical characteristics. RESULTS: The ORs associated for high-grade serous ovarian cancer were 3.01 for PALB2 (95% CI 1.59 to 5.68; p=0.00068), 1.99 for POLK (95% CI 1.15 to 3.43; p=0.014) and 4.07 for SLX4 (95% CI 1.34 to 12.4; p=0.013). Deleterious mutations in FBXO10 were associated with a reduced risk of disease (OR 0.27, 95% CI 0.07 to 1.00, p=0.049). However, based on the Bayes false discovery probability, only the association for PALB2 in high-grade serous ovarian cancer is likely to represent a true positive. CONCLUSIONS: We have found strong evidence that carriers of PALB2 deleterious mutations are at increased risk of high-grade serous ovarian cancer. Whether the magnitude of risk is sufficiently high to warrant the inclusion of PALB2 in cancer gene panels for ovarian cancer risk testing is unclear; much larger sample sizes will be needed to provide sufficiently precise estimates for clinical counselling.

9.
BMC Cancer ; 20(1): 369, 2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32357859

RESUMO

BACKGROUND: Familial cases of appendiceal mucinous tumours (AMTs) are extremely rare and the underlying genetic aetiology uncertain. We identified potential predisposing germline genetic variants in a father and daughter with AMTs presenting with pseudomyxoma peritonei (PMP) and correlated these with regions of loss of heterozygosity (LOH) in the tumours. METHODS: Through germline whole exome sequencing, we identified novel heterozygous loss-of-function (LoF) (i.e. nonsense, frameshift and essential splice site mutations) and missense variants shared between father and daughter, and validated all LoF variants, and missense variants with a Combined Annotation Dependent Depletion (CADD) scaled score of ≥10. Genome-wide copy number analysis was performed on tumour tissue from both individuals to identify regions of LOH. RESULTS: Fifteen novel variants in 15 genes were shared by the father and daughter, including a nonsense mutation in REEP5. None of these germline variants were located in tumour regions of LOH shared by the father and daughter. Four genes (EXOG, RANBP2, RANBP6 and TNFRSF1B) harboured missense variants that fell in a region of LOH in the tumour from the father only, but none showed somatic loss of the wild type allele in the tumour. The REEP5 gene was sequenced in 23 individuals with presumed sporadic AMTs or PMP; no LoF or rare missense germline variants were identified. CONCLUSION: Germline exome sequencing of a father and daughter with AMTs identified novel candidate predisposing genes. Further studies are required to clarify the role of these genes in familial AMTs.

10.
Nat Commun ; 11(1): 1640, 2020 04 02.
Artigo em Inglês | MEDLINE | ID: mdl-32242007

RESUMO

High-grade serous ovarian carcinoma (HGSOC) has a significant hereditary component, approximately half of which cannot be explained by known genes. To discover genes, we analyse germline exome sequencing data from 516 BRCA1/2-negative women with HGSOC, focusing on genes enriched with rare, protein-coding loss-of-function (LoF) variants. Overall, there is a significant enrichment of rare protein-coding LoF variants in the cases (p < 0.0001, chi-squared test). Only thirty-four (6.6%) have a pathogenic variant in a known or proposed predisposition gene. Few genes have LoF mutations in more than four individuals and the majority are detected in one individual only. Forty-three highly-ranked genes are identified with three or more LoF variants that are enriched by three-fold or more compared to GnomAD. These genes represent diverse functional pathways with relatively few involved in DNA repair, suggesting that much of the remaining heritability is explained by previously under-explored genes and pathways.


Assuntos
Cistadenocarcinoma Seroso/genética , Exoma , Heterogeneidade Genética , Predisposição Genética para Doença , Neoplasias Ovarianas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Coortes , Cistadenocarcinoma Seroso/patologia , Feminino , Humanos , Mutação com Perda de Função , Pessoa de Meia-Idade , Neoplasias Ovarianas/patologia , Sequenciamento Completo do Exoma , Adulto Jovem
11.
NPJ Breast Cancer ; 6: 9, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32195332

RESUMO

Intraductal papillomas (IDP) are challenging breast findings because of their variable risk of progression to malignancy. The molecular events driving IDP development and genomic features of malignant progression are poorly understood. In this study, genome-wide CNA and/or targeted mutation analysis was performed on 44 cases of IDP, of which 20 cases had coexisting ductal carcinoma in situ (DCIS), papillary DCIS or invasive ductal carcinoma (IDC). CNA were rare in pure IDP, but 69% carried an activating PIK3CA mutation. Among the synchronous IDP cases, 55% (11/20) were clonally related to the synchronous DCIS and/or IDC, only one of which had papillary histology. In contrast to pure IDP, PIK3CA mutations were absent from clonal cases. CNAs in any of chromosomes 1, 16 or 11 were significantly enriched in clonal IDP lesions compared to pure and non-clonal IDP. The observation that 55% of IDP are clonal to DCIS/IDC indicates that IDP can be a direct precursor for breast carcinoma, not limited to the papillary type. The absence of PIK3CA mutations and presence of CNAs in IDP could be used clinically to identify patients at high risk of progression to carcinoma.

12.
Gynecol Oncol ; 156(3): 552-560, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31902686

RESUMO

OBJECTIVE: Mucinous ovarian carcinoma (MOC) is an uncommon ovarian cancer histotype that responds poorly to conventional chemotherapy regimens. Although long overall survival outcomes can occur with early detection and optimal surgical resection, recurrent and advanced disease are associated with extremely poor survival. There are no current guidelines specifically for the systemic management of recurrent MOC. We analyzed data from a large cohort of women with MOC to evaluate the potential for clinical utility from a range of systemic agents. METHODS: We analyzed gene copy number (n = 191) and DNA sequencing data (n = 184) from primary MOC to evaluate signatures of mismatch repair deficiency and homologous recombination deficiency, and other genetic events. Immunohistochemistry data were collated for ER, CK7, CK20, CDX2, HER2, PAX8 and p16 (n = 117-166). RESULTS: Molecular aberrations noted in MOC that suggest a match with current targeted therapies include amplification of ERBB2 (26.7%) and BRAF mutation (9%). Observed genetic events that suggest potential efficacy for agents currently in clinical trials include: KRAS/NRAS mutations (66%), TP53 missense mutation (49%), RNF43 mutation (11%), ARID1A mutation (10%), and PIK3CA/PTEN mutation (9%). Therapies exploiting homologous recombination deficiency (HRD) may not be effective in MOC, as only 1/191 had a high HRD score. Mismatch repair deficiency was similarly rare (1/184). CONCLUSIONS: Although genetically diverse, MOC has several potential therapeutic targets. Importantly, the lack of response to platinum-based therapy observed clinically corresponds to the lack of a genomic signature associated with HRD, and MOC are thus also unlikely to respond to PARP inhibition.


Assuntos
Adenocarcinoma Mucinoso/genética , Adenocarcinoma Mucinoso/terapia , Neoplasias Ovarianas/genética , Neoplasias Ovarianas/terapia , Adenocarcinoma Mucinoso/metabolismo , Adenocarcinoma Mucinoso/patologia , Idoso , Estudos de Coortes , Reparo de Erro de Pareamento de DNA , Feminino , Recombinação Homóloga , Humanos , Imuno-Histoquímica , Mutação , Estadiamento de Neoplasias , Neoplasias Ovarianas/metabolismo , Neoplasias Ovarianas/patologia , Receptor ErbB-2/genética , Receptor ErbB-3/genética
13.
Cancer Res ; 80(3): 624-638, 2020 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-31723001

RESUMO

Pathogenic sequence variants (PSV) in BRCA1 or BRCA2 (BRCA1/2) are associated with increased risk and severity of prostate cancer. We evaluated whether PSVs in BRCA1/2 were associated with risk of overall prostate cancer or high grade (Gleason 8+) prostate cancer using an international sample of 65 BRCA1 and 171 BRCA2 male PSV carriers with prostate cancer, and 3,388 BRCA1 and 2,880 BRCA2 male PSV carriers without prostate cancer. PSVs in the 3' region of BRCA2 (c.7914+) were significantly associated with elevated risk of prostate cancer compared with reference bin c.1001-c.7913 [HR = 1.78; 95% confidence interval (CI), 1.25-2.52; P = 0.001], as well as elevated risk of Gleason 8+ prostate cancer (HR = 3.11; 95% CI, 1.63-5.95; P = 0.001). c.756-c.1000 was also associated with elevated prostate cancer risk (HR = 2.83; 95% CI, 1.71-4.68; P = 0.00004) and elevated risk of Gleason 8+ prostate cancer (HR = 4.95; 95% CI, 2.12-11.54; P = 0.0002). No genotype-phenotype associations were detected for PSVs in BRCA1. These results demonstrate that specific BRCA2 PSVs may be associated with elevated risk of developing aggressive prostate cancer. SIGNIFICANCE: Aggressive prostate cancer risk in BRCA2 mutation carriers may vary according to the specific BRCA2 mutation inherited by the at-risk individual.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Predisposição Genética para Doença , Genômica/métodos , Mutação , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Estudos de Associação Genética , Heterozigoto , Humanos , Masculino , Pessoa de Meia-Idade , Prognóstico , Fatores de Risco , Adulto Jovem
14.
J Natl Cancer Inst ; 111(12): 1332-1338, 2019 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-30949688

RESUMO

BACKGROUND: Loss-of-function variants in RAD51C are associated with familial ovarian cancer, but its role in hereditary breast cancer remains unclear. The aim of this study was to couple breast tumor sequencing with case-control data to clarify the contribution of RAD51C to hereditary breast cancer. METHODS: RAD51C was sequenced in 3080 breast cancer index cases that were negative in BRCA1/2 clinical tests and 4840 population-matched cancer-free controls. Pedigree and pathology data were analyzed. Nine breast cancers and one ovarian cancer from RAD51C variant carriers were sequenced to identify biallelic inactivation of RAD51C, copy number variation, mutational signatures, and the spectrum of somatic mutations in breast cancer driver genes. The promoter of RAD51C was analyzed for DNA methylation. RESULTS: A statistically significant excess of loss-of-function variants was identified in 3080 cases (0.4%) compared with 2 among 4840 controls (0.04%; odds ratio = 8.67, 95% confidence interval = 1.89 to 80.52, P< .001), with more than half of the carriers having no personal or family history of ovarian cancer. In addition, the association was highly statistically significant among cases with estrogen-negative (P <. 001) or triple-negative cancer (P < .001), but not in estrogen-positive cases. Tumor sequencing from carriers confirmed bi-allelic inactivation in all the triple-negative cases and was associated with high homologous recombination deficiency scores and mutational signature 3 indicating homologous recombination repair deficiency. CONCLUSIONS: This study provides evidence that germline loss-of-function variants of RAD51C are associated with hereditary breast cancer, particularly triple-negative type. RAD51C-null breast cancers possess similar genomic and clinical features to BRCA1-null cancers and may also be vulnerable to DNA double-strand break inducing chemotherapies and poly ADP-ribose polymerase inhibitors.


Assuntos
Neoplasias da Mama/genética , Carcinoma Ductal de Mama/genética , Proteínas de Ligação a DNA/genética , Inativação Gênica , Mutação em Linhagem Germinativa , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias da Mama/química , Estudos de Casos e Controles , Metilação de DNA , Feminino , Dosagem de Genes , Instabilidade Genômica , Humanos , Pessoa de Meia-Idade , Mutação , Neoplasias Ovarianas/genética , Regiões Promotoras Genéticas , Receptores Estrogênicos , Análise de Sequência de DNA , Neoplasias de Mama Triplo Negativas/genética , Adulto Jovem
15.
Cancer Prev Res (Phila) ; 12(6): 383-390, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31003994

RESUMO

Individualized screening is our logical next step to improve population breast cancer screening in Australia. To explore breast screening participants' views of the current program in Victoria, Australia, examine their openness to change, and attitudes toward an individualized screening model, this qualitative work was performed from a population-based breast screening cohort. This work was designed to inform the development of a decision aid to facilitate women's decisions about participating in individualized screening, and to elicit Australian consumer perspectives on the international movement toward individualized breast screening. A total of 52 women participated in one of four focus groups, and were experienced with screening with 90% of participants having had more than three mammograms. Focus group discussion was facilitated following three main themes: (i) experience of breast screening; (ii) breast cancer risk perception, and (iii) views on individualized screening. Participants had strong, positive, emotional ties to breast screening in its current structure but were supportive, with some reservations, of the idea of individualized screening. There was good understanding about the factors contributing to personalized risk and a wide range of opinions about the inclusion of genetic testing with genetic testing being considered a foreign and evolving domain. Individualized breast screening that takes account of risk factors such as mammographic density, lifestyle, and genetic factors would be acceptable to a population of women who are invested in the current system. The communication and implementation of a new program would be critical to its acceptance and potential success. Reservations may be had in regards to uptake of genetic testing, motivations behind the change, and management of the women allocated to a lower risk category.


Assuntos
Neoplasias da Mama/diagnóstico , Neoplasias da Mama/psicologia , Tomada de Decisões , Detecção Precoce de Câncer/psicologia , Conhecimentos, Atitudes e Prática em Saúde , Mamografia/psicologia , Aceitação pelo Paciente de Cuidados de Saúde , Idoso , Progressão da Doença , Feminino , Seguimentos , Humanos , Pessoa de Meia-Idade , Prognóstico
16.
J Pathol ; 248(3): 326-338, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30843206

RESUMO

The current model for breast cancer progression proposes independent 'low grade (LG)-like' and 'high grade (HG)-like' pathways but lacks a known precursor to HG cancer. We applied low-coverage whole-genome sequencing to atypical ductal hyperplasia (ADH) with and without carcinoma to shed light on breast cancer progression. Fourteen out of twenty isolated ADH cases harboured at least one copy number alteration (CNA), but had fewer aberrations than LG or HG ductal carcinoma in situ (DCIS). ADH carried more HG-like CNA than LG DCIS (e.g. 8q gain). Correspondingly, 64% (7/11) of ADH cases with synchronous HG carcinoma were clonally related, similar to LG carcinoma (67%, 6/9). This study represents a significant shift in our understanding of breast cancer progression, with ADH as a common precursor lesion to the independent 'low grade-like' and 'high grade-like' pathways. These data suggest that ADH can be a precursor of HG breast cancer and that LG and HG carcinomas can evolve from a similar ancestor lesion. We propose that although LG DCIS may be committed to a LG molecular pathway, ADH may remain multipotent, progressing to either LG or HG carcinoma. This multipotent nature suggests that some ADH cases could be more clinically significant than LG DCIS, requiring biomarkers for personalising management. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Neoplasias da Mama/patologia , Carcinoma Ductal de Mama/patologia , Carcinoma Intraductal não Infiltrante/patologia , Hiperplasia/patologia , Mama/patologia , Carcinoma de Mama in situ/patologia , Carcinoma in Situ/patologia , Feminino , Humanos , Lesões Pré-Cancerosas/patologia
17.
Exp Physiol ; 104(6): 920-931, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30919515

RESUMO

NEW FINDINGS: What is the central question of this study? To what extent are the mechanical-ventilatory responses to upper-body exercise influenced by task-specific locomotor mechanics? What is the main finding and its importance? When compared with lower-body exercise performed at similar ventilations, upper-body exercise was characterized by tidal volume constraint, dynamic lung hyperinflation and an increased propensity towards neuromechanical uncoupling of the respiratory system. Importantly, these responses were independent of respiratory dysfunction and flow limitation. Thus, the mechanical ventilatory responses to upper-body exercise are attributable, in part, to task-specific locomotor mechanics (i.e. non-respiratory loading of the thorax). ABSTRACT: The aim of this study was to determine the extent to which the mechanical ventilatory responses to upper-body exercise are influenced by task-specific locomotor mechanics. Eight healthy men (mean ± SD: age, 24 ± 5 years; mass, 74 ± 11 kg; and stature, 1.79 ± 0.07 m) completed two maximal exercise tests, on separate days, comprising 4 min stepwise increments of 15 W during upper-body exercise (arm-cranking) or 30 W during lower-body exercise (leg-cycling). The tests were repeated at work rates calculated to elicit 20, 40, 60, 80 and 100% of the peak ventilation achieved during arm-cranking ( V ̇ E , UBE ). Exercise measures included pulmonary ventilation and gas exchange, oesophageal pressure-derived indices of respiratory mechanics, operating lung volumes and expiratory flow limitation. Subjects exhibited normal resting pulmonary function. Arm-crank exercise elicited significantly lower peak values for work rate, O2 uptake, CO2 output, minute ventilation and tidal volume (p < 0.05). At matched ventilations, arm-crank exercise restricted tidal volume expansion relative to leg-cycling exercise at 60% V ̇ E , UBE (1.74 ± 0.61 versus 2.27 ± 0.68 l, p < 0.001), 80% V ̇ E , UBE (2.07 ± 0.70 versus 2.52 ± 0.67 l, p < 0.001) and 100% V ̇ E , UBE (1.97 ± 0.85 versus 2.55 ± 0.72 l, p = 0.002). Despite minimal evidence of expiratory flow limitation, expiratory reserve volume was significantly higher during arm-cranking versus leg-cycling exercise at 100% V ̇ E , UBE (39 ± 8 versus 29 ± 8% of vital capacity, p = 0.002). At any given ventilation, arm-cranking elicited greater inspiratory effort (oesophageal pressure) relative to thoracic displacement (tidal volume). Arm-cranking exercise is sufficient to provoke respiratory mechanical derangements (restricted tidal volume expansion, dynamic hyperinflation and neuromechanical uncoupling) in subjects with normal pulmonary function and expiratory flow reserve. These responses are likely to be attributable to task-specific locomotor mechanics (i.e. non-respiratory loading of the thorax).


Assuntos
Exercício Físico/fisiologia , Pulmão/fisiologia , Ventilação Pulmonar/fisiologia , Adulto , Teste de Esforço , Humanos , Masculino , Consumo de Oxigênio/fisiologia , Testes de Função Respiratória , Adulto Jovem
18.
J Pathol ; 248(2): 243-252, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-30746706

RESUMO

Breast cancer (BC) diagnosed after a negative mammogram but prior to the next screening episode is termed an 'interval BC' (IBC). Understanding the molecular differences between IBC and screen-detected BCs (SDBC) could improve mammographic screening and management options. Therefore, we assessed both germline and somatic genomic aberrations in a prospective cohort. Utilising the Lifepool cohort of >54 000 women attending mammographic screening programs, 930 BC cases with screening status were identified (726 SDBC and 204 IBC). Clinico-pathological and family history information were recorded. Germline and tumour DNA were collected where available and sequenced for BC predisposition and driver gene mutations. Compared to SDBC, IBCs were significantly associated with a younger age at diagnosis and tumour characteristics associated with worse prognosis. Germline DNA assessment of BC cases that developed post-enrolment (276 SDBCs and 77 IBCs) for pathogenic mutations in 12 hereditary BC predisposition genes identified 8 carriers (2.27%). The germline mutation frequency was higher in IBC versus SDBC, although not statistically significant (3.90% versus 1.81%, p = 0.174). Comparing somatic genetic features of IBC and SDBC matched for grade, histological subtype and hormone receptor revealed no significant differences, with the exception of higher homologous recombination deficiency scores in IBC, and copy number changes on chromosome Xq in triple negative SDBCs. Our data demonstrates that while IBCs are clinically more aggressive than SDBC, when matched for confounding clinico-pathological features they do not represent a unique molecular class of invasive BC, but could be a consequence of timing of tumour initiation and mammographic screening. Copyright © 2019 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Biomarcadores Tumorais/genética , Neoplasias da Mama/diagnóstico por imagem , Neoplasias da Mama/genética , Detecção Precoce de Câncer/métodos , Mutação em Linhagem Germinativa , Mamografia , Adulto , Idoso , Idoso de 80 Anos ou mais , Variações do Número de Cópias de DNA , Feminino , Dosagem de Genes , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Taxa de Mutação , Fenótipo , Valor Preditivo dos Testes , Prognóstico , Estudos Prospectivos , Sistema de Registros , Vitória
19.
Cancer Cell ; 35(2): 256-266.e5, 2019 02 11.
Artigo em Inglês | MEDLINE | ID: mdl-30753826

RESUMO

Biallelic germline mutations affecting NTHL1 predispose carriers to adenomatous polyposis and colorectal cancer, but the complete phenotype is unknown. We describe 29 individuals carrying biallelic germline NTHL1 mutations from 17 families, of which 26 developed one (n = 10) or multiple (n = 16) malignancies in 14 different tissues. An unexpected high breast cancer incidence was observed in female carriers (60%). Mutational signature analysis of 14 tumors from 7 organs revealed that NTHL1 deficiency underlies the main mutational process in all but one of the tumors (93%). These results reveal NTHL1 as a multi-tumor predisposition gene with a high lifetime risk for extracolonic cancers and a typical mutational signature observed across tumor types, which can assist in the recognition of this syndrome.


Assuntos
Biomarcadores Tumorais/genética , Análise Mutacional de DNA , Desoxirribonuclease (Dímero de Pirimidina)/genética , Perfilação da Expressão Gênica , Mutação em Linhagem Germinativa , Síndromes Neoplásicas Hereditárias/genética , Transcriptoma , Adulto , Idoso , Biomarcadores Tumorais/deficiência , Reparo do DNA/genética , Desoxirribonuclease (Dímero de Pirimidina)/deficiência , Europa (Continente) , Feminino , Regulação Neoplásica da Expressão Gênica , Predisposição Genética para Doença , Hereditariedade , Humanos , Masculino , Pessoa de Meia-Idade , Síndromes Neoplásicas Hereditárias/enzimologia , Síndromes Neoplásicas Hereditárias/patologia , Linhagem , Fenótipo , Medição de Risco , Fatores de Risco , Adulto Jovem
20.
PLoS One ; 14(1): e0210649, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30668606

RESUMO

Despite sleep's recognized biological importance, it has been remarkably difficult to demonstrate changes in brain physiology with reduced sleep durations. In a study of adolescents, we varied sleep durations by restricting time in bed for four nights of either 10, 8.5 or 7 h. Shorter sleep durations significantly decreased waking electroencephalogram (EEG) power in a wide range of frequencies with both eyes closed and eyes open in central and occipital leads. These findings suggest new research directions and raise the possibility that waking EEG power density could provide a non-invasive test for biologically sufficient sleep.


Assuntos
Eletroencefalografia/métodos , Sono/fisiologia , Vigília/fisiologia , Adolescente , Encéfalo/fisiologia , Criança , Feminino , Humanos , Estudos Longitudinais , Masculino , Fases do Sono/fisiologia , Sono REM/fisiologia
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