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1.
Int J Cancer ; 2020 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-32930401

RESUMO

In our study, we evaluated the effectiveness of upper gastrointestinal (GI) endoscopy as an instrument for early gastric cancer (GC) detection in Lynch syndrome (LS) patients by analyzing data from the registry of the German Consortium for Familial Intestinal Cancer. In a prospective, multicenter cohort study, 1128 out of 2009 registered individuals with confirmed LS underwent 5176 upper GI endoscopies. Compliance was good since 77.6% of upper GI endoscopies were completed within the recommended interval of 1 to 3 years. Forty-nine GC events were observed in 47 patients. MLH1 (n = 21) and MSH2 (n = 24) mutations were the most prevalent. GCs in patients undergoing regular surveillance were diagnosed significantly more often in an early-stage disease (UICC I) than GCs detected through symptoms (83% vs 25%; P = .0231). Thirty-two (68%) patients had a negative family history of GC. The median age at diagnosis was 51 years (range 28-66). Of all GC patients, 13 were diagnosed at an age younger than 45. Our study supports the recommendation of regular upper GI endoscopy surveillance for LS patients beginning no later than at the age of 30.

2.
Bone Joint J ; 102-B(10): 1405-1411, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32993326

RESUMO

AIMS: This exploratory randomized controlled trial (RCT) aimed to determine the splint-related outcomes when using the novel biodegradable wood-composite splint (Woodcast) compared to standard synthetic fibreglass (Dynacast) for the immobilization of undisplaced upper limb fractures in children. METHODS: An exploratory RCT was performed at a tertiary paediatric referral hospital between 1 June 2018 and 30 September 2019. The intention-to-treat population consisted of 170 patients (mean age 8.42 years (SD 3.42); Woodcast (WCG), n = 84, 57 male (67.9%); Dynacast (DNG), n = 86, 58 male (67.4%)). Patients with undisplaced upper limb fractures were randomly assigned to WCG or DNG treatment groups. Primary outcome was the stress stability of the splint material, defined as absence of any deformations or fractures within the splint during study period. Secondary outcomes included patient satisfaction and medical staff opinion. Additionally, biomechanical and chemical analysis of the splint samples was carried out. RESULTS: Of the initial 170 patients, 168 (98.8%) completed at least one follow-up, and were included for analysis of the primary endpoint. Both treatment groups were well-matched regarding to age, sex, and type and localization of the fracture. Splint breakage occurred in three patients (3.6%; 95% confidence interval (CI), 0.007% to 0.102%) in the WCG and in three children (3.5%, 95% CI 0.007% to 0.09%) in the DNG (p > 0.99). The incidence of splint-related adverse events did not differ between the WCG (n = 21; 25.0%) and DNG (n = 24; 27.9%; p = 0.720). Under experimental conditions, the maximal tensile strength of Dynacast samples was higher than those deriving from Woodcast (mean 15.37 N/mm² (SD 1.37) vs 10.75 N/mm² (SD 1.20); p = 0.002). Chemical analysis revealed detection of polyisocyanate-prepolymer in Dynacast and polyester in Woodcast samples. CONCLUSION: Splint-related adverse events appear similar between WCG and DNG treatment groups during the treatment of undisplaced forearm fractures. Cite this article: Bone Joint J 2020;102-B(10):1405-1411.


Assuntos
Traumatismos do Braço/terapia , Fraturas Ósseas/terapia , Contenções , Adolescente , Criança , Pré-Escolar , Feminino , Vidro , Humanos , Imobilização , Lactente , Análise de Intenção de Tratamento , Masculino , Desenho de Prótese , Madeira
3.
Death Stud ; : 1-10, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32972330

RESUMO

We evaluated 2,865 elderly people to investigate the prevalence of prolonged grief disorder (PGD), examine predictors and mental health correlates. The conditional prevalence of PGD varied between 0.8% and 5.2% (diagnostic algorithm vs. cut-off). PG-13 scores were related to depressive symptoms, sleep disturbances, reduced life satisfaction, and quality of life. Predictors were female gender, less time since death, more losses, having lost a child, partner, or sibling, and less social support. PGD is associated with adverse mental health consequences. Practitioners should pay special attention to elderly women who lost a close loved one and lack social support.

4.
Int J Cancer ; 147(10): 2801-2810, 2020 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-32875553

RESUMO

BRAF V600E mutations have been reported as a marker of sporadic microsatellite instability (MSI) colorectal cancer (CRC). Current international diagnostic guidelines recommend BRAF mutation testing in MSI CRC patients to predict low risk of Lynch syndrome (LS). We evaluated the age-specific performance of BRAF testing in LS diagnostics. We systematically compared the prevalence of BRAF mutations in LS-associated CRCs and unselected MSI CRCs in different age groups as available from published studies, databases and population-based patient cohorts. Sensitivity/specificity analysis of BRAF testing for exclusion of LS and cost calculations were performed. Among 969 MSI CRCs from LS carriers in the literature and German HNPCC Consortium, 15 (1.6%) harbored BRAF mutations. Six of seven LS patients with BRAF-mutant CRC and reported age were <50 years. Among 339 of 756 (44.8%) of BRAF mutations detected in unselected MSI CRC, only 2 of 339 (0.6%) BRAF mutations were detected in patients <50 years. The inclusion of BRAF testing led to high risk of missing LS patients and increased costs at age <50 years. BRAF testing in patients <50 years carries a high risk of missing a hereditary cancer predisposition and is cost-inefficient. We suggest direct referral of MSI CRC patients <50 years to genetic counseling without BRAF testing.

5.
Brain Sci ; 10(9)2020 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-32824904

RESUMO

The term fatigue is not only used to describe a sleepy state with a lack of drive, as observed in patients with chronic physical illnesses, but also a state with an inhibition of drive and central nervous system (CNS) hyperarousal, as frequently observed in patients with major depression. An electroencephalogram (EEG)-based algorithm has been developed to objectively assess CNS arousal and to disentangle these pathophysiologically heterogeneous forms of fatigue. The aim of this study was to test the hypothesis that fatigued patients with CNS hyperarousal score higher on depressive symptoms than those without this neurophysiological pattern. METHODS: Subjects with fatigue (Multidimensional Fatigue Inventory sum-score > 40) in the context of cancer, neuroinflammatory, or autoimmune diseases were drawn from the 60+ cohort of the Leipzig Research Center for Civilization Diseases. CNS arousal was assessed by automatic EEG-vigilance stage classification using the Vigilance Algorithm Leipzig (VIGALL 2.1) based on 20 min EEG recordings at rest with eyes closed. Depression was assessed by the Inventory of Depressive Symptomatology (IDS-SR). RESULTS: Sixty participants (33 female; median age: 67.5 years) were included in the analysis. As hypothesized, fatigued patients with CNS hyperarousal had higher IDS-SR scores than those without hyperarousal (F1,58 = 18.34; p < 0.0001, η2 = 0.240). CONCLUSION: hyperaroused fatigue in patients with chronic physical illness may be a sign of comorbid depression.

7.
JAMA Oncol ; 6(8): 1218-1230, 2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32614418

RESUMO

Importance: The limited data on cancer phenotypes in men with germline BRCA1 and BRCA2 pathogenic variants (PVs) have hampered the development of evidence-based recommendations for early cancer detection and risk reduction in this population. Objective: To compare the cancer spectrum and frequencies between male BRCA1 and BRCA2 PV carriers. Design, Setting, and Participants: Retrospective cohort study of 6902 men, including 3651 BRCA1 and 3251 BRCA2 PV carriers, older than 18 years recruited from cancer genetics clinics from 1966 to 2017 by 53 study groups in 33 countries worldwide collaborating through the Consortium of Investigators of Modifiers of BRCA1/2 (CIMBA). Clinical data and pathologic characteristics were collected. Main Outcomes and Measures: BRCA1/2 status was the outcome in a logistic regression, and cancer diagnoses were the independent predictors. All odds ratios (ORs) were adjusted for age, country of origin, and calendar year of the first interview. Results: Among the 6902 men in the study (median [range] age, 51.6 [18-100] years), 1634 cancers were diagnosed in 1376 men (19.9%), the majority (922 of 1,376 [67%]) being BRCA2 PV carriers. Being affected by any cancer was associated with a higher probability of being a BRCA2, rather than a BRCA1, PV carrier (OR, 3.23; 95% CI, 2.81-3.70; P < .001), as well as developing 2 (OR, 7.97; 95% CI, 5.47-11.60; P < .001) and 3 (OR, 19.60; 95% CI, 4.64-82.89; P < .001) primary tumors. A higher frequency of breast (OR, 5.47; 95% CI, 4.06-7.37; P < .001) and prostate (OR, 1.39; 95% CI, 1.09-1.78; P = .008) cancers was associated with a higher probability of being a BRCA2 PV carrier. Among cancers other than breast and prostate, pancreatic cancer was associated with a higher probability (OR, 3.00; 95% CI, 1.55-5.81; P = .001) and colorectal cancer with a lower probability (OR, 0.47; 95% CI, 0.29-0.78; P = .003) of being a BRCA2 PV carrier. Conclusions and Relevance: Significant differences in the cancer spectrum were observed in male BRCA2, compared with BRCA1, PV carriers. These data may inform future recommendations for surveillance of BRCA1/2-associated cancers and guide future prospective studies for estimating cancer risks in men with BRCA1/2 PVs.

8.
J Clin Med ; 9(7)2020 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-32708519

RESUMO

PURPOSE: To survey risk-reducing hysterectomy and bilateral salpingo-oophorectomy (BSO) practice and advice regarding hormone replacement therapy (HRT) in women with Lynch syndrome. METHODS: We conducted a survey in 31 contributing centers from the Prospective Lynch Syndrome Database (PLSD), which incorporates 18 countries worldwide. The survey covered local policies for risk-reducing hysterectomy and BSO in Lynch syndrome, the timing when these measures are offered, the involvement of stakeholders and advice regarding HRT. RESULTS: Risk-reducing hysterectomy and BSO are offered to path_MLH1 and path_MSH2 carriers in 20/21 (95%) contributing centers, to path_MSH6 carriers in 19/21 (91%) and to path_PMS2 carriers in 14/21 (67%). Regarding the involvement of stakeholders, there is global agreement (~90%) that risk-reducing surgery should be offered to women, and that this discussion may involve gynecologists, genetic counselors and/or medical geneticists. Prescription of estrogen-only HRT is offered by 15/21 (71%) centers to women of variable age range (35-55 years). CONCLUSIONS: Most centers offer risk-reducing gynecological surgery to carriers of path_MLH1, path_MSH2 and path_MSH6 variants but less so for path_PMS2 carriers. There is wide variation in how, when and to whom this is offered. The Manchester International Consensus Group developed recommendations to harmonize clinical practice across centers, but there is a clear need for more research.

9.
Int J Cancer ; 2020 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-32683684

RESUMO

Individuals with Lynch syndrome (LS), one of the most common inherited cancer syndromes, are at increased risk of developing malignancies, in particular colorectal cancer (CRC). Regular colonoscopy with polypectomy is recommended to reduce CRC risk in LS individuals. However, recent independent studies demonstrated that a substantial proportion of LS individuals develop CRC despite regular colonoscopy. The reasons for this surprising observation confirmed by large prospective studies are a matter of debate. In this review, we collect existing evidence from clinical, epidemiological and molecular studies and interpret them with regard to the origins and progression of LS-associated CRC. Alongside with hypotheses addressing colonoscopy quality and pace of progression from adenoma to cancer, we discuss the role of alternative precursors and immune system in LS-associated CRC. We also identify gaps in current knowledge and make suggestions for future studies aiming at improved CRC prevention for LS individuals.

10.
Oncol Res Treat ; 43(9): 414-427, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32580190

RESUMO

BACKGROUND: Venous thromboembolism (VTE) is a common complication of cancer. This study aimed to evaluate immature platelet fraction (IPF), mean platelet volume (MPV), P-selectin, D-dimer, and thrombin generation (TG) as predictive biomarkers for VTE and further the improvement of existing risk assessment models (RAMs). METHODS: A prospective, observational, exploratory study was conducted on ambulatory cancer patients with indication for systemic chemotherapy. Baseline RAMs included the Khorana-, Vienna Cancer, Thrombosis-, Protecht-, ONKOTEV-, and Catscore. IPF, MPV, P-selectin, D-dimer, and TG were analysed at baseline and 3-month follow-up. RESULTS: We enrolled 100 patients, of whom 89 completed the follow-up. Frequent tumour types were breast (30%), gastric (14%), gynaecological (14%), and colorectal (14%) cancer. Ten of the 89 patients (11.2%) developed VTE. The highest VTE rate was observed in patients with cholangiocarcinoma (3/5; 60%). Baseline D-dimer levels but not IPF, MPV, or P-selectin were associated with the risk of developing VTE (HR 6.9; p = 0.021). None of the RAMs showed statistical significance in predicting VTE. Peak thrombin and endogenous thrombin potential were lower in patients who developed VTE. Biomarker changes between baseline and follow-up were not associated with VTE risk. CONCLUSIONS: VTE risk was well predicted by baseline D-dimer levels. Adding D-dimer could improve existing RAMs to better identify patients who may benefit from primary VTE prophylaxis. The VTE risk among patients with cholangiocarcinoma should be further evaluated.

11.
Nat Commun ; 11(1): 2828, 2020 06 05.
Artigo em Inglês | MEDLINE | ID: mdl-32504003

RESUMO

The TATA-binding protein (TBP) and a transcription factor (TF) IIB-like factor are important constituents of all eukaryotic initiation complexes. The reason for the emergence and strict requirement of the additional initiation factor Bdp1 in the RNA polymerase (RNAP) III system, however, remained elusive. A poorly studied aspect in this context is the effect of DNA strain arising from DNA compaction and transcriptional activity on initiation complex formation. We made use of a DNA origami-based force clamp to follow the assembly of human initiation complexes in the RNAP II and RNAP III systems at the single-molecule level under piconewton forces. We demonstrate that TBP-DNA complexes are force-sensitive and TFIIB is sufficient to stabilise TBP on a strained promoter. In contrast, Bdp1 is the pivotal component that ensures stable anchoring of initiation factors, and thus the polymerase itself, in the RNAP III system. Thereby, we offer an explanation for the crucial role of Bdp1 for the high transcriptional output of RNAP III.


Assuntos
DNA de Cadeia Simples/metabolismo , RNA Polimerase III/metabolismo , Imagem Individual de Molécula/métodos , Fator de Transcrição TFIIIB/metabolismo , Transcrição Genética , DNA de Cadeia Simples/química , DNA de Cadeia Simples/ultraestrutura , Transferência Ressonante de Energia de Fluorescência , Cinética , Microscopia Confocal , Microscopia Eletrônica de Transmissão , Sondas Moleculares/química , Sondas Moleculares/metabolismo , Sondas Moleculares/ultraestrutura , Conformação de Ácido Nucleico , Regiões Promotoras Genéticas , Estabilidade Proteica , RNA Polimerase III/química , Proteínas Recombinantes/metabolismo , Proteína de Ligação a TATA-Box/metabolismo
12.
PLoS One ; 15(5): e0233016, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32413055

RESUMO

Tunneled central venous catheters (TCVCs) provide prolonged intravenous access for pediatric patients with severe primary immunodeficiency disease (PID) undergoing hematopoietic stem cell transplantation (HSCT). However, little is known about the epidemiology and clinical significance of TCVC-related morbidity in this particular patient group. We conducted the retrospective analysis of patients with severe PID who received percutaneous landmark-guided TCVC implantation prior to HSCT. We analyzed 92 consecutive TCVC implantations in 69 patients (median [interquartile range] age 3.0 [0-11] years) with severe combined immune deficiency (n = 39, 42.4%), chronic granulomatous disease (n = 17, 18.4%), and other rare PID syndromes (n = 36, 39.2%). The median length of TCVC observation was 144.1 (85.5-194.6) days with a total of 14,040 catheter days at risk (cdr). The overall rate of adverse events during catheter insertion was 17.4% (n = 16) and 25.0% during catheter dwell period (n = 23, catheter risk [CR] per 1000 cdr = 1.64). The most common complication was TCVC-related infection with an overall prevalence of 9.8% (n = 9, CR = 0.64), followed by late dislocation (n = 6, 6.5%, CR = 0.43), early dislocation (n = 4, 4.3%) and catheter dysfunction (n = 4, 4.3%, CR = 0.28). TCVCs are safe in children with severe PID undergoing HSCT with relatively low rates of TCVC-related infection.


Assuntos
Cateteres Venosos Centrais/efeitos adversos , Transplante de Células-Tronco Hematopoéticas , Doenças da Imunodeficiência Primária/terapia , Infecções Relacionadas a Cateter/epidemiologia , Infecções Relacionadas a Cateter/etiologia , Cateterismo Venoso Central/efeitos adversos , Cateterismo Venoso Central/métodos , Criança , Pré-Escolar , Feminino , Alemanha/epidemiologia , Doença Granulomatosa Crônica/terapia , Humanos , Lactente , Recém-Nascido , Masculino , Morbidade , Estudos Retrospectivos , Fatores de Risco , Segurança , Imunodeficiência Combinada Severa/terapia
13.
BMC Cancer ; 20(1): 460, 2020 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-32448342

RESUMO

BACKGROUND: Individuals with pathogenic germline variants in DNA mismatch repair (MMR) genes are at increased risk of developing colorectal, endometrial and other cancers (Lynch syndrome, LS). While previous studies have extensively described cancer risks in LS, cancer risks in individuals from families without detectable MMR gene defects despite MMR deficiency (Lynch-like syndrome, LLS), and in individuals from families fulfilling the Amsterdam-II criteria without any signs of MMR deficiency (familial colorectal cancer type X, FCCX) are less well studied. The aim of this prospective study was to characterise the risk for different cancer types in LS, LLS, and FCCX, and to compare these with the cancer risks in the general population. METHODS: Data was taken from the registry of the German Consortium for Familial Intestinal Cancer, where individuals were followed up prospectively within the framework of an intensified surveillance programme at recommended annual examination intervals. A total of 1120 LS, 594 LLS, and 116 FCCX individuals were analysed. From this total sample, eight different cohorts were defined, in which age-dependent cumulative risks and standardised incidence ratios were calculated regarding the first incident occurrence of any, colorectal, stomach, small bowel, urothelial, female breast, ovarian, and endometrial cancer, separately for LS, LLS, and FCCX. RESULTS: The number of individuals at risk for first incident cancer ranged from 322 to 1102 in LS, 120 to 586 in LLS, and 40 to 116 in FCCX, depending on the cancer type of interest. For most cancer types, higher risks were observed in LS compared to LLS, FCCX, and the general population. Risks for any, colorectal, stomach, urothelial, and endometrial cancer were significantly higher in LLS compared to the general population. No significantly increased risks could be detected in FCCX compared to LLS patients, and the general population. Colorectal and endometrial cancer risks tended to be higher in LLS than in FCCX. CONCLUSIONS: The characterisation of cancer risks in patients with LLS and FCCX is important to develop appropriate surveillance programmes for these specific intermediate risk groups. Larger prospective studies are needed to obtain more precise risk estimates.

14.
J Voice ; 2020 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-32402662

RESUMO

OBJECTIVES: The voice range profile (VRP) is composed of the speaking VRP (spVRP) and the singing VRP (siVRP). Different examination methods of VRP and effects of interobserver variability were evaluated to define a standard operating procedure (SOP) suitable for the specific use in epidemiological studies. Subsequently the feasibility of the SOP was investigated in a larger number of participants. STUDY DESIGN: Cross-sectional study. METHODS: In a first phase both the spVRP and the siVRP of 51 female students were measured by four differently experienced examiners. Using a cross-over study design the effects of two different recording methods (manual vs automatic) and three different types of instructions given by the examiner (none vs before vs during recording) were investigated. In a second phase, the SOP for VRP recording was tested in the framework of a feasibility study in 110 (55 female and 55 male) participants. RESULTS: The average total investigation time was significantly (P = 0.001) higher for the manual recording method (6.1 minutes ± 1.0) in comparison to the automated (5.5 minutes ± 0.7) recording method. The manual recording method led to significantly lower values of minimum frequency (F0min) (P = 0.013) and minimum intensity (SPLmin) (P < 0.001) and higher values of the maximum frequency (F0max) (P = 0.005) of the siVRP. The maximum phonation time, F0max, SPLmax of the siVRP and the frequency and intensity of the shouting voice (Level IV) of the spVRP showed significantly (P < 0.001) higher values when the examiner was allowed to give instructions and advise during the recording. Voice parameters of the siVRP did not show significant associations with the experience of the examiner. CONCLUSIONS: Standardization of VRP measurements is important to obtain correct and reproducible data in a reasonable examination time. The SOP proposed here proved to be feasible in the setting of an epidemiological study.

15.
Nat Commun ; 11(1): 1206, 2020 03 05.
Artigo em Inglês | MEDLINE | ID: mdl-32139698

RESUMO

Transcription of the ribosomal RNA precursor by RNA polymerase (Pol) I is a prerequisite for the biosynthesis of ribosomes in eukaryotes. Compared to Pols II and III, the mechanisms underlying promoter recognition, initiation complex formation and DNA melting by Pol I substantially diverge. Here, we report the high-resolution cryo-EM reconstruction of a Pol I early initiation intermediate assembled on a double-stranded promoter scaffold that prevents the establishment of downstream DNA contacts. Our analyses demonstrate how efficient promoter-backbone interaction is achieved by combined re-arrangements of flexible regions in the 'core factor' subunits Rrn7 and Rrn11. Furthermore, structure-function analysis illustrates how destabilization of the melted DNA region correlates with contraction of the polymerase cleft upon transcription activation, thereby combining promoter recruitment with DNA-melting. This suggests that molecular mechanisms and structural features of Pol I initiation have co-evolved to support the efficient melting, initial transcription and promoter clearance required for high-level rRNA synthesis.


Assuntos
Regiões Promotoras Genéticas , RNA Polimerase I/metabolismo , Saccharomyces cerevisiae/genética , Iniciação da Transcrição Genética , Sequência de Aminoácidos , DNA/química , DNA/ultraestrutura , Modelos Moleculares , Estrutura Secundária de Proteína , Subunidades Proteicas/metabolismo , RNA Polimerase I/química , RNA Polimerase I/ultraestrutura , Fator de Transcrição TFIIB/metabolismo
17.
J Natl Cancer Inst ; 2020 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-32107557

RESUMO

BACKGROUND: The purpose of this study was to estimate precise age-specific tubo-ovarian carcinoma (TOC) and breast cancer (BC) risks for carriers of pathogenic variants in RAD51C and RAD51D. METHODS: We analysed data from 6178 families, 125 with pathogenic variants in RAD51C; and 6690 families, 60 with pathogenic variants in RAD51D. TOC and BC relative and cumulative risks were estimated using complex segregation analysis to model the cancer inheritance patterns in families, while adjusting for the mode of ascertainment of each family. All statistical tests were two-sided. RESULTS: Pathogenic variants in both RAD51C and RAD51D were associated with TOC (RAD51C RR = 7.55, 95%CI:5.60-10.19, p = 5 × 10-40; RAD51D RR = 7.60, 95%CI:5.61-10.30, p = 5 × 10-39) and BC (RAD51C RR = 1.99, 95%CI:1.39-2.85, p = 1.55 × 10-4; RAD51D RR = 1.83, 95%CI:1.24-2.72, p = 0.002). For both RAD51C and RAD51D, there was a suggestion that the TOC RRs increased with age until around age 60 years and decreased thereafter. The estimated cumulative risks of developing TOC to age 80 were 11% (95%CI:6-21%) for RAD51C and 13% (95%CI:7-23%) for RAD51D pathogenic variant carriers. The estimated cumulative risks of developing BC to 80 were 21% (95%CI:15-29%) for RAD51C and 20% (95%CI:14-28%) for RAD51D pathogenic variant carriers. Both TOC and BC risks for RAD51C/D pathogenic variant carriers varied by cancer family history, and could be as high as 32-36% for TOC, for carriers with two first degree relatives diagnosed with TOC; or 44-46% for BC, for carriers with two first degree relatives diagnosed with BC. CONCLUSIONS: These estimates will facilitate the genetic counselling of RAD51C and RAD51D pathogenic variant carriers and justify the incorporation of RAD51C and RAD51D into cancer risk prediction models.

18.
J Biol Chem ; 295(15): 4782-4795, 2020 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-32060094

RESUMO

RNA polymerase I (Pol I) is a highly efficient enzyme specialized in synthesizing most ribosomal RNAs. After nucleosome deposition at each round of rDNA replication, the Pol I transcription machinery has to deal with nucleosomal barriers. It has been suggested that Pol I-associated factors facilitate chromatin transcription, but it is unknown whether Pol I has an intrinsic capacity to transcribe through nucleosomes. Here, we used in vitro transcription assays to study purified WT and mutant Pol I variants from the yeast Saccharomyces cerevisiae and compare their abilities to pass a nucleosomal barrier with those of yeast Pol II and Pol III. Under identical conditions, purified Pol I and Pol III, but not Pol II, could transcribe nucleosomal templates. Pol I mutants lacking either the heterodimeric subunit Rpa34.5/Rpa49 or the C-terminal part of the specific subunit Rpa12.2 showed a lower processivity on naked DNA templates, which was even more reduced in the presence of a nucleosome. Our findings suggest that the lobe-binding subunits Rpa34.5/Rpa49 and Rpa12.2 facilitate passage through nucleosomes, suggesting possible cooperation among these subunits. We discuss the contribution of Pol I-specific subunit domains to efficient Pol I passage through nucleosomes in the context of transcription rate and processivity.

19.
Gastroenterology ; 158(5): 1326-1333, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-31926173

RESUMO

BACKGROUND & AIMS: Lynch syndrome is caused by variants in DNA mismatch repair (MMR) genes and associated with an increased risk of colorectal cancer (CRC). In patients with Lynch syndrome, CRCs can develop via different pathways. We studied associations between Lynch syndrome-associated variants in MMR genes and risks of adenoma and CRC and somatic mutations in APC and CTNNB1 in tumors in an international cohort of patients. METHODS: We combined clinical and molecular data from 3 studies. We obtained clinical data from 2747 patients with Lynch syndrome associated with variants in MLH1, MSH2, or MSH6 from Germany, the Netherlands, and Finland who received at least 2 surveillance colonoscopies and were followed for a median time of 7.8 years for development of adenomas or CRC. We performed DNA sequence analyses of 48 colorectal tumors (from 16 patients with mutations in MLH1, 29 patients with mutations in MSH2, and 3 with mutations in MSH6) for somatic mutations in APC and CTNNB1. RESULTS: Risk of advanced adenoma in 10 years was 17.8% in patients with pathogenic variants in MSH2 vs 7.7% in MLH1 (P < .001). Higher proportions of patients with pathogenic variants in MLH1 or MSH2 developed CRC in 10 years (11.3% and 11.4%) than patients with pathogenic variants in MSH6 (4.7%) (P = .001 and P = .003 for MLH1 and MSH2 vs MSH6, respectively). Somatic mutations in APC were found in 75% of tumors from patients with pathogenic variants in MSH2 vs 11% in MLH1 (P = .015). Somatic mutations in CTNNB1 were found in 50% of tumors from patients with pathogenic variants in MLH1 vs 7% in MSH2 (P = .002). None of the 3 tumors with pathogenic variants in MSH6 had a mutation in CTNNB1, but all had mutations in APC. CONCLUSIONS: In an analysis of clinical and DNA sequence data from patients with Lynch syndrome from 3 countries, we associated pathogenic variants in MMR genes with risk of adenoma and CRC, and somatic mutations in APC and CTNNB1 in colorectal tumors. If these findings are confirmed, surveillance guidelines might be adjusted based on MMR gene variants.


Assuntos
Adenoma/epidemiologia , Neoplasias Colorretais Hereditárias sem Polipose/epidemiologia , Proteínas de Ligação a DNA/genética , Proteína 1 Homóloga a MutL/genética , Proteína 2 Homóloga a MutS/genética , Adenoma/diagnóstico , Adenoma/genética , Proteína da Polipose Adenomatosa do Colo/genética , Adulto , Colonoscopia , Neoplasias Colorretais Hereditárias sem Polipose/diagnóstico , Neoplasias Colorretais Hereditárias sem Polipose/genética , Reparo de Erro de Pareamento de DNA , Análise Mutacional de DNA , Feminino , Finlândia/epidemiologia , Alemanha/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Mutação , Países Baixos/epidemiologia , Estudos Prospectivos , beta Catenina/genética
20.
Breast Cancer Res ; 22(1): 8, 2020 01 16.
Artigo em Inglês | MEDLINE | ID: mdl-31948486

RESUMO

BACKGROUND: The effect of risk-reducing salpingo-oophorectomy (RRSO) on breast cancer risk for BRCA1 and BRCA2 mutation carriers is uncertain. Retrospective analyses have suggested a protective effect but may be substantially biased. Prospective studies have had limited power, particularly for BRCA2 mutation carriers. Further, previous studies have not considered the effect of RRSO in the context of natural menopause. METHODS: A multi-centre prospective cohort of 2272 BRCA1 and 1605 BRCA2 mutation carriers was followed for a mean of 5.4 and 4.9 years, respectively; 426 women developed incident breast cancer. RRSO was modelled as a time-dependent covariate in Cox regression, and its effect assessed in premenopausal and postmenopausal women. RESULTS: There was no association between RRSO and breast cancer for BRCA1 (HR = 1.23; 95% CI 0.94-1.61) or BRCA2 (HR = 0.88; 95% CI 0.62-1.24) mutation carriers. For BRCA2 mutation carriers, HRs were 0.68 (95% CI 0.40-1.15) and 1.07 (95% CI 0.69-1.64) for RRSO carried out before or after age 45 years, respectively. The HR for BRCA2 mutation carriers decreased with increasing time since RRSO (HR = 0.51; 95% CI 0.26-0.99 for 5 years or longer after RRSO). Estimates for premenopausal women were similar. CONCLUSION: We found no evidence that RRSO reduces breast cancer risk for BRCA1 mutation carriers. A potentially beneficial effect for BRCA2 mutation carriers was observed, particularly after 5 years following RRSO. These results may inform counselling and management of carriers with respect to RRSO.


Assuntos
Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/epidemiologia , Mutação , Salpingo-Ooforectomia/métodos , Adulto , Neoplasias da Mama/genética , Neoplasias da Mama/patologia , Neoplasias da Mama/cirurgia , Estudos de Coortes , Feminino , Humanos , Incidência , Agências Internacionais , Menopausa , Pessoa de Meia-Idade , Estudos Prospectivos , Comportamento de Redução do Risco
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