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1.
J Med Genet ; 60(3): 265-273, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36763037

RESUMO

BACKGROUND: Ashkenazi Jewish (AJ) people have a higher incidence of BRCA1/2 pathogenic variants (PVs) than unselected populations. Three BRCA-Jewish founder mutations (B-JFMs) comprise >90% of BRCA1/2 PVs in AJ people. Personal/family cancer history-based testing misses ≥50% of people with B-JFM. METHODS: We compared two population-based B-JFM screening programmes in Australia-using (1) an online tool (Sydney) and (2) in-person group sessions (Melbourne). RESULTS: Of 2167 Jewish people tested (Sydney n=594; Melbourne n=1573), 1.3% (n=28) have a B-JFM, only 2 of whom had a significant cancer family history (Manchester score ≥12). Pretest anxiety scores were normal (mean 9.9±3.5 (6-24)), with no significant post-result change (9.5±3.3). Decisional regret (mean 7.4±13.0 (0-100)), test-related distress (mean 0.8+/2.2 (0-30)) and positive experiences (reverse-scored) (mean 3.4±4.5 (1-20)) scores were low, with no significant differences between Sydney and Melbourne participants. Post-education knowledge was good overall (mean 11.8/15 (±2.9)) and significantly higher in Melbourne than Sydney. Post-result knowledge was the same (mean 11.7 (±2.4) vs 11.2 (±2.4)). Participants with a B-JFM had higher post-result anxiety and test-related distress and lower positive experiences, than those without a B-JFM, but scores were within the normal range. Family cancer history did not significantly affect knowledge or anxiety, or pretest perception of B-JFM or cancer risks. Most participants (93%) were satisfied/very satisfied with the programme. CONCLUSION: Both B-JFM screening programmes are highly acceptable to Australian Jewish communities. The programme enabled identification of several individuals who were previously unaware they have a B-JFM, many of whom would have been ineligible for current criteria-based testing in Australia.


Assuntos
Neoplasias da Mama , Neoplasias , Humanos , Feminino , Testes Genéticos/métodos , Judeus/genética , Predisposição Genética para Doença , Austrália , Proteína BRCA1/genética , Neoplasias/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Mutação
2.
Mod Pathol ; 34(1): 194-206, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-32724153

RESUMO

TP53 mutations are implicated in the progression of mucinous borderline tumors (MBOT) to mucinous ovarian carcinomas (MOC). Optimized immunohistochemistry (IHC) for TP53 has been established as a proxy for the TP53 mutation status in other ovarian tumor types. We aimed to confirm the ability of TP53 IHC to predict TP53 mutation status in ovarian mucinous tumors and to evaluate the association of TP53 mutation status with survival among patients with MBOT and MOC. Tumor tissue from an initial cohort of 113 women with MBOT/MOC was stained with optimized IHC for TP53 using tissue microarrays (75.2%) or full sections (24.8%) and interpreted using established criteria as normal or abnormal (overexpression, complete absence, or cytoplasmic). Cases were considered concordant if abnormal IHC staining predicted deleterious TP53 mutations. Discordant tissue microarray cases were re-evaluated on full sections and interpretational criteria were refined. The initial cohort was expanded to a total of 165 MBOT and 424 MOC for the examination of the association of survival with TP53 mutation status, assessed either by TP53 IHC and/or sequencing. Initially, 82/113 (72.6%) cases were concordant using the established criteria. Refined criteria for overexpression to account for intratumoral heterogeneity and terminal differentiation improved concordance to 93.8% (106/113). In the expanded cohort, 19.4% (32/165) of MBOT showed evidence for TP53 mutation and this was associated with a higher risk of recurrence, disease-specific death, and all-cause mortality (overall survival: HR = 4.6, 95% CI 1.5-14.3, p = 0.0087). Within MOC, 61.1% (259/424) harbored a TP53 mutation, but this was not associated with survival (overall survival, p = 0.77). TP53 IHC is an accurate proxy for TP53 mutation status with refined interpretation criteria accounting for intratumoral heterogeneity and terminal differentiation in ovarian mucinous tumors. TP53 mutation status is an important biomarker to identify MBOT with a higher risk of mortality.


Assuntos
Biomarcadores Tumorais/genética , Análise Mutacional de DNA , Imuno-Histoquímica , Mutação , Neoplasias Císticas, Mucinosas e Serosas/genética , Neoplasias Ovarianas/genética , Proteína Supressora de Tumor p53/genética , Adulto , Austrália , Feminino , Humanos , Pessoa de Meia-Idade , Neoplasias Císticas, Mucinosas e Serosas/mortalidade , Neoplasias Císticas, Mucinosas e Serosas/patologia , Neoplasias Císticas, Mucinosas e Serosas/terapia , América do Norte , Variações Dependentes do Observador , Neoplasias Ovarianas/mortalidade , Neoplasias Ovarianas/patologia , Neoplasias Ovarianas/terapia , Valor Preditivo dos Testes , Prognóstico , Reprodutibilidade dos Testes , Medição de Risco , Fatores de Risco , Análise Serial de Tecidos , Reino Unido
3.
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
4.
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
5.
Genet Med ; 21(4): 913-922, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30254378

RESUMO

PURPOSE: The identification of carriers of hereditary breast and ovarian cancer (HBOC) gene variants through family cancer history alone is suboptimal, and most population-based genetic testing studies have been limited to founder mutations in high-risk populations. Here, we determine the clinical utility of identifying actionable variants in a healthy cohort of women. METHODS: Germline DNA from a subset of healthy Australian women participating in the lifepool project was screened using an 11-gene custom sequencing panel. Women with clinically actionable results were invited to attend a familial cancer clinic (FCC) for post-test genetic counseling and confirmatory testing. Outcomes measured included the prevalence of pathogenic variants, and the uptake rate of genetic counseling, risk reduction surgery, and cascade testing. RESULTS: Thirty-eight of 5908 women (0.64%) carried a clinically actionable pathogenic variant. Forty-two percent of pathogenic variant carriers did not have a first-degree relative with breast or ovarian cancer and 89% pursued referral to an FCC. Forty-six percent (6/13) of eligible women pursued risk reduction surgery, and the uptake rate of cascade testing averaged 3.3 family members per index case. CONCLUSION: Within our cohort, HBOC genetic testing was well accepted, and the majority of high-risk gene carriers identified would not meet eligibility criteria for genetic testing based on their existing family history.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Síndrome Hereditária de Câncer de Mama e Ovário/genética , Neoplasias Ovarianas/genética , Idoso , Austrália , Neoplasias da Mama/patologia , Feminino , Aconselhamento Genético , Genética Populacional , Mutação em Linhagem Germinativa/genética , Síndrome Hereditária de Câncer de Mama e Ovário/patologia , Heterozigoto , Humanos , Pessoa de Meia-Idade , Mutação , Neoplasias Ovarianas/patologia
6.
J Pathol ; 245(1): 53-60, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29431189

RESUMO

PALB2 is established as the most clinically important moderate to high penetrance breast cancer predisposition gene after BRCA1 and BRCA2. Mutations in classical familial cancer predisposition genes are presumed to be recessive at the cellular level and therefore a second inactivating somatic mutation is required in the tumour tissue. However, from the limited data that exist, PALB2 may be an example of a cancer predisposition gene that does not conform to Knudson's 'two hit' paradigm. We conducted genome-wide copy number analysis and targeted sequencing of PALB2 and other breast cancer driver genes in 15 invasive breast cancers from individuals carrying pathogenic germline mutations in PALB2. The majority of cancers showed clear evidence of bi-allelic inactivation of PALB2 (10/15) either as loss of heterozygosity involving the wild-type allele (six tumours) or as somatic point mutations (four tumours). All PALB2-null cancers had high homologous recombination deficiency (HRD) scores consistent with a homologous recombination repair deficiency. Interestingly, all but one of the PALB2 heterozygous cancers also had high HRD scores, suggesting that alternative mechanisms of PALB2 functional loss might be operating in these cancers. Our findings demonstrate that PALB2 does undergo bi-allelic inactivation in the majority of breast cancers from PALB2 germline mutation carriers. This feature has implications for the discovery of new moderate to high penetrance breast cancer predisposition genes as it supports using the existence of a 'second hit' and mutation signatures as important search criteria. Copyright © 2018 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.


Assuntos
Neoplasias da Mama/patologia , Proteína do Grupo de Complementação N da Anemia de Fanconi/genética , Predisposição Genética para Doença , Mutação em Linhagem Germinativa/genética , Mutação/genética , Proteína BRCA2/genética , Neoplasias da Mama/genética , Humanos , Reparo de DNA por Recombinação/genética , Proteínas Supressoras de Tumor/genética
7.
Breast Cancer Res ; 20(1): 3, 2018 01 09.
Artigo em Inglês | MEDLINE | ID: mdl-29316957

RESUMO

BACKGROUND: Genome-wide association studies (GWASs) have identified numerous single-nucleotide polymorphisms (SNPs) associated with small increases in breast cancer risk. Studies to date suggest that some SNPs alter the expression of the associated genes, which potentially mediates risk modification. On this basis, we hypothesised that some of these genes may be enriched for rare coding variants associated with a higher breast cancer risk. METHODS: The coding regions and exon-intron boundaries of 56 genes that have either been proposed by GWASs to be the regulatory targets of the SNPs and/or located < 500 kb from the risk SNPs were sequenced in index cases from 1043 familial breast cancer families that previously had negative test results for BRCA1 and BRCA2 mutations and 944 population-matched cancer-free control participants from an Australian population. Rare (minor allele frequency ≤ 0.001 in the Exome Aggregation Consortium and Exome Variant Server databases) loss-of-function (LoF) and missense variants were studied. RESULTS: LoF variants were rare in both the cases and control participants across all the candidate genes, with only 38 different LoF variants observed in a total of 39 carriers. For the majority of genes (n = 36), no LoF variants were detected in either the case or control cohorts. No individual gene showed a significant excess of LoF or missense variants in the cases compared with control participants. Among all candidate genes as a group, the total number of carriers with LoF variants was higher in the cases than in the control participants (26 cases and 13 control participants), as was the total number of carriers with missense variants (406 versus 353), but neither reached statistical significance (p = 0.077 and p = 0.512, respectively). The genes contributing most of the excess of LoF variants in the cases included TET2, NRIP1, RAD51B and SNX32 (12 cases versus 2 control participants), whereas ZNF283 and CASP8 contributed largely to the excess of missense variants (25 cases versus 8 control participants). CONCLUSIONS: Our data suggest that rare LoF and missense variants in genes associated with low-penetrance breast cancer risk SNPs may contribute some additional risk, but as a group these genes are unlikely to be major contributors to breast cancer heritability.


Assuntos
Neoplasias da Mama/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Mutação com Perda de Função/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Austrália , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/patologia , Caspase 8/genética , Proteínas de Ligação a DNA/genética , Dioxigenases , Feminino , Frequência do Gene , Heterozigoto , Humanos , Pessoa de Meia-Idade , Mutação de Sentido Incorreto , Proteína 1 de Interação com Receptor Nuclear/genética , Penetrância , Polimorfismo de Nucleotídeo Único/genética , Proteínas Proto-Oncogênicas/genética
8.
Breast Cancer Res Treat ; 159(2): 385-92, 2016 09.
Artigo em Inglês | MEDLINE | ID: mdl-27544226

RESUMO

Rad50 interactor 1 (RINT1) has recently been reported as an intermediate-penetrance (odds ratio 3.24) breast cancer susceptibility gene, as well as a risk factor for Lynch syndrome. The coding regions and exon-intron boundaries of RINT1 were sequenced in 2024 familial breast cancer cases previously tested negative for BRCA1, BRCA2, and PALB2 mutations and 1886 population-matched cancer-free controls using HaloPlex Targeted Enrichment Assays. Only one RINT1 protein-truncating variant was detected in a control. No excess was observed in the total number of rare variants (truncating and missense) (28, 1.38 %, vs. 27, 1.43 %. P > 0.999) or in the number of variants predicted to be pathogenic by various in silico tools (Condel, Polyphen2, SIFT, and CADD) in the cases compared to the controls. In addition, there was no difference in the incidence of classic Lynch syndrome cancers in RINT1 rare variant-carrying families compared to RINT1 wild-type families. This study had 90 % power to detect an odds ratio of at least 2.06, and the results do not provide any support for RINT1 being a moderate-penetrance breast cancer susceptibility gene, although larger studies will be required to exclude more modest effects. This study emphasizes the need for caution before designating a cancer predisposition role for any gene based on very rare truncating variants and in silico-predicted missense variants.


Assuntos
Neoplasias da Mama/genética , Proteínas de Ciclo Celular/genética , Mutação , Análise de Sequência de DNA/métodos , Adolescente , Adulto , Idoso , Neoplasias Colorretais Hereditárias sem Polipose/genética , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Taxa de Mutação , Penetrância , População Branca/genética , Adulto Jovem
9.
Breast Cancer Res ; 17: 111, 2015 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-26283626

RESUMO

INTRODUCTION: PALB2 is emerging as a high-penetrance breast cancer predisposition gene in the order of BRCA1 and BRCA2. However, large studies that have evaluated the full gene rather than just the most common variants in both cases and controls are required before all truncating variants can be included in familial breast cancer variant testing. METHODS: In this study we analyse almost 2000 breast cancer cases sourced from individuals referred to familial cancer clinics, thus representing typical cases presenting in clinical practice. These cases were compared to a similar number of population-based cancer-free controls. RESULTS: We identified a significant excess of truncating variants in cases (1.3 %) versus controls (0.2 %), including six novel variants (p = 0.0001; odds ratio (OR) 6.58, 95 % confidence interval (CI) 2.3-18.9). Three of the four control individuals carrying truncating variants had at least one relative with breast cancer. There was no excess of missense variants in cases overall, but the common c.1676A > G variant (rs152451) was significantly enriched in cases and may represent a low-penetrance polymorphism (p = 0.002; OR 1.24 (95 % CI 1.09-1.47). CONCLUSIONS: Our findings support truncating variants in PALB2 as high-penetrance breast cancer susceptibility alleles, and suggest that a common missense variant may also lead to a low level of increased breast cancer risk.


Assuntos
Mutação/genética , Proteínas Nucleares/genética , Proteínas Supressoras de Tumor/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Austrália , Neoplasias da Mama/genética , Estudos de Casos e Controles , Proteína do Grupo de Complementação N da Anemia de Fanconi , Predisposição Genética para Doença/genética , Humanos , Pessoa de Meia-Idade , Prevalência , Risco , Adulto Jovem
10.
Mod Pathol ; 28(9): 1174-84, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26321097

RESUMO

Ductal carcinoma in situ (DCIS) is a non-obligate precursor of invasive breast cancer and a frequent mammographic finding requiring treatment. Up to 25% of DCIS can recur and half of recurrences are invasive, but there are no reliable biomarkers for recurrence. We hypothesised that copy number aberrations could predict likelihood of recurrence. We analysed a cohort of pure DCIS cases treated only with wide local excision for genome-wide copy number and loss of heterozygosity using Affymetrix OncoScan MIP arrays. Cases included those without recurrence within 7 years (n = 25) and with recurrence between 1 and 5 years after diagnosis (n = 15). Pure DCIS were broadly similar in copy number changes compared with invasive breast cancer, with the consistent exception of a greater frequency of ERBB2 amplification in DCIS. There were no significant differences in age or ER status between the cases with a recurrence vs those without. Overall, the DCIS cases with recurrence had more copy number events than the DCIS without recurrence. The increased copy number appeared non-random with several genomic regions showing an increase in frequency in recurrent cases, including 20 q gain, ERBB2 amplification and 15q loss. Copy number changes may provide prognostic information for DCIS recurrence, but validation in additional cohorts is required.


Assuntos
Neoplasias da Mama/genética , Carcinoma Intraductal não Infiltrante/genética , Recidiva Local de Neoplasia/genética , Idoso , Feminino , Dosagem de Genes , Humanos , Imuno-Histoquímica , Pessoa de Meia-Idade , Análise de Sequência com Séries de Oligonucleotídeos , Reação em Cadeia da Polimerase
11.
PLoS Genet ; 8(9): e1002894, 2012 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23028338

RESUMO

Despite intensive efforts using linkage and candidate gene approaches, the genetic etiology for the majority of families with a multi-generational breast cancer predisposition is unknown. In this study, we used whole-exome sequencing of thirty-three individuals from 15 breast cancer families to identify potential predisposing genes. Our analysis identified families with heterozygous, deleterious mutations in the DNA repair genes FANCC and BLM, which are responsible for the autosomal recessive disorders Fanconi Anemia and Bloom syndrome. In total, screening of all exons in these genes in 438 breast cancer families identified three with truncating mutations in FANCC and two with truncating mutations in BLM. Additional screening of FANCC mutation hotspot exons identified one pathogenic mutation among an additional 957 breast cancer families. Importantly, none of the deleterious mutations were identified among 464 healthy controls and are not reported in the 1,000 Genomes data. Given the rarity of Fanconi Anemia and Bloom syndrome disorders among Caucasian populations, the finding of multiple deleterious mutations in these critical DNA repair genes among high-risk breast cancer families is intriguing and suggestive of a predisposing role. Our data demonstrate the utility of intra-family exome-sequencing approaches to uncover cancer predisposition genes, but highlight the major challenge of definitively validating candidates where the incidence of sporadic disease is high, germline mutations are not fully penetrant, and individual predisposition genes may only account for a tiny proportion of breast cancer families.


Assuntos
Neoplasias da Mama/genética , Proteína do Grupo de Complementação C da Anemia de Fanconi/genética , RecQ Helicases/genética , Deleção de Sequência/genética , Alelos , Exoma/genética , Éxons , Proteína do Grupo de Complementação C da Anemia de Fanconi/metabolismo , Feminino , Predisposição Genética para Doença , Genoma Humano , Humanos , Linhagem , Polimorfismo Genético , RecQ Helicases/metabolismo , Análise de Sequência de DNA
12.
J Pathol ; 229(3): 469-76, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23096461

RESUMO

Mucinous carcinomas represent a distinct morphological subtype which can arise from several organ sites, including the ovary, and their genetic characteristics are largely under-described. Exome sequencing of 12 primary mucinous ovarian tumours identified RNF43 as the most frequently somatically mutated novel gene, secondary to KRAS and mutated at a frequency equal to that of TP53 and BRAF. Further screening of RNF43 in a larger cohort of ovarian tumours identified additional mutations, with a total frequency of 2/22 (9%) in mucinous ovarian borderline tumours and 6/29 (21%) in mucinous ovarian carcinomas. Seven mutations were predicted to truncate the protein and one missense mutation was predicted to be deleterious by in silico analysis. Six tumours had allelic imbalance at the RNF43 locus, with loss of the wild-type allele. The mutation spectrum strongly suggests that RNF43 is an important tumour suppressor gene in mucinous ovarian tumours, similar to its reported role in mucinous pancreatic precancerous cysts.


Assuntos
Adenocarcinoma Mucinoso/genética , Cistadenoma Mucinoso/genética , Proteínas de Ligação a DNA/genética , Genes Supressores de Tumor/fisiologia , Mutação , Proteínas Oncogênicas/genética , Neoplasias Ovarianas/genética , Adenocarcinoma Mucinoso/patologia , Simulação por Computador , Cistadenoma Mucinoso/patologia , Análise Mutacional de DNA , DNA de Neoplasias/análise , Proteínas de Ligação a DNA/metabolismo , Exoma/genética , Feminino , Humanos , Modelos Moleculares , Proteínas Oncogênicas/metabolismo , Neoplasias Ovarianas/patologia , Análise de Sequência de DNA , Ubiquitina-Proteína Ligases
13.
Ann Neurol ; 71(4): 487-97, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22522441

RESUMO

OBJECTIVE: Friedreich ataxia (FA) is the most common ataxia and results from an expanded GAA repeat in the first intron of FXN. This leads to epigenetic modifications and reduced frataxin. We investigated the relationships between genetic, epigenetic, and clinical parameters in a large case-control study of FA. METHODS: Clinical data and samples were obtained from individuals with FA during annual visits to our dedicated FA clinic. GAA expansions were evaluated by polymerase chain reaction (PCR) and restriction endonuclease digest. DNA methylation was measured using bisulfite-based EpiTYPER MassARRAY (Sequenom, San Diego, CA). FXN expression was determined using real-time reverse transcriptase PCR. Significant correlations between the different parameters were examined using the nonparametric Spearman rank correlation coefficient, as well as univariate and multivariate regression modeling. RESULTS: Characteristic DNA methylation was identified upstream and downstream of the expansion, and validated in an independent FA cohort. Univariate and multivariate analyses showed significant inverse correlations between upstream methylation and FXN expression, and variation in downstream methylation and age of onset. FXN expression also inversely correlated with the Friedreich Ataxia Rating Scale score, an indicator of disease severity. INTERPRETATION: These novel findings provide compelling evidence for the link between the GAA expansion, the DNA methylation profile, FXN expression, and clinical outcome in FA. Epigenetic profiling of FXN could be used to gain greater insight into disease onset and progression, but also as a biomarker to learn more about specific treatment responses and pharmacological mechanism(s). This work also highlights the potential for developing therapies aimed at increasing frataxin levels to treat this debilitating disease.


Assuntos
Metilação de DNA/genética , Ataxia de Friedreich/genética , Marcadores Genéticos/genética , Proteínas de Ligação ao Ferro/genética , Expansão das Repetições de Trinucleotídeos/genética , Adolescente , Adulto , Idoso , Estudos de Casos e Controles , Criança , Progressão da Doença , Epigênese Genética , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sequências Repetitivas de Ácido Nucleico , Adulto Jovem , Frataxina
14.
J Natl Cancer Inst ; 115(2): 181-189, 2023 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-36315097

RESUMO

BACKGROUND: Breast cancers (BCs) that arise in individuals heterozygous for a germline pathogenic variant in a susceptibility gene, such as BRCA1 and BRCA2, PALB2, and RAD51C, have been shown to exhibit biallelic loss in the respective genes and be associated with triple-negative breast cancer (TNBC) and distinctive somatic mutational signatures. Tumor sequencing thus presents an orthogonal approach to assess the role of candidate genes in BC development. METHODS: Exome sequencing was performed on paired normal-breast tumor DNA from 124 carriers of germline loss-of-function (LoF) or missense variant carriers in 15 known and candidate BC predisposition genes identified in the BEACCON case-control study. Biallelic inactivation and association with tumor genome features including mutational signatures and homologous recombination deficiency (HRD) score were investigated. RESULTS: BARD1-carrying TNBC (4 of 5) displayed biallelic loss and associated high HRD scores and mutational signature 3, as did a RAD51D-carrying TNBC and ovarian cancer. Biallelic loss was less frequent in BRIP1 BCs (4 of 13) and had low HRD scores. In contrast to other established BC genes, BCs from carriers of CHEK2 LoF (6 of 17) or missense (2 of 20) variant had low rates of biallelic loss. Exploratory analysis of BC from carriers of LoF variants in candidate genes such as BLM, FANCM, PARP2, and RAD50 found little evidence of biallelic inactivation. CONCLUSIONS: BARD1 and RAD51D behave as classic BRCA-like predisposition genes with biallelic inactivation, but this was not observed for any of the candidate genes. However, as demonstrated for CHEK2, the absence of biallelic inactivation does not provide definitive evidence against the gene's involvement in BC predisposition.


Assuntos
Neoplasias da Mama , Neoplasias de Mama Triplo Negativas , Feminino , Humanos , Neoplasias da Mama/patologia , Neoplasias de Mama Triplo Negativas/genética , Estudos de Casos e Controles , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Genes BRCA2 , DNA Helicases/genética
15.
Nat Med ; 29(7): 1681-1691, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37291213

RESUMO

Critically ill infants and children with rare diseases need equitable access to rapid and accurate diagnosis to direct clinical management. Over 2 years, the Acute Care Genomics program provided whole-genome sequencing to 290 families whose critically ill infants and children were admitted to hospitals throughout Australia with suspected genetic conditions. The average time to result was 2.9 d and diagnostic yield was 47%. We performed additional bioinformatic analyses and transcriptome sequencing in all patients who remained undiagnosed. Long-read sequencing and functional assays, ranging from clinically accredited enzyme analysis to bespoke quantitative proteomics, were deployed in selected cases. This resulted in an additional 19 diagnoses and an overall diagnostic yield of 54%. Diagnostic variants ranged from structural chromosomal abnormalities through to an intronic retrotransposon, disrupting splicing. Critical care management changed in 120 diagnosed patients (77%). This included major impacts, such as informing precision treatments, surgical and transplant decisions and palliation, in 94 patients (60%). Our results provide preliminary evidence of the clinical utility of integrating multi-omic approaches into mainstream diagnostic practice to fully realize the potential of rare disease genomic testing in a timely manner.


Assuntos
Estado Terminal , Doenças Raras , Lactente , Criança , Humanos , Doenças Raras/diagnóstico , Doenças Raras/genética , Doenças Raras/terapia , Multiômica , Sequenciamento Completo do Genoma/métodos , Sequenciamento do Exoma
16.
NPJ Breast Cancer ; 8(1): 10, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35039523

RESUMO

While protein-truncating variants in RAD51C have been shown to predispose to triple-negative (TN) breast cancer (BC) and ovarian cancer, little is known about the pathogenicity of missense (MS) variants. The frequency of rare RAD51C MS variants was assessed in the BEACCON study of 5734 familial BC cases and 14,382 population controls, and findings were integrated with tumour sequencing data from 21 cases carrying a candidate variant. Collectively, a significant enrichment of rare MS variants was detected in cases (MAF < 0.001, OR 1.57, 95% CI 1.00-2.44, p = 0.05), particularly for variants with a REVEL score >0.5 (OR 3.95, 95% CI 1.40-12.01, p = 0.006). Sequencing of 21 tumours from 20 heterozygous and 1 homozygous carriers of nine candidate MS variants identified four cases with biallelic inactivation through loss of the wild-type allele, while six lost the variant allele and ten that remained heterozygous. Biallelic loss of the wild-type alleles corresponded strongly with ER- and TN breast tumours, high homologous recombination deficiency scores and mutational signature 3. Using this approach, the p.Gly264Ser variant, which was previously suspected to be pathogenic based on small case-control analyses and loss of activity in in vitro functional assays, was shown to be benign with similar prevalence in cases and controls and seven out of eight tumours showing no biallelic inactivation or characteristic mutational signature. Conversely, evaluation of case-control findings and tumour sequencing data identified p.Ile144Thr, p.Arg212His, p.Gln143Arg and p.Gly114Arg as variants warranting further investigation.

17.
BMJ Open ; 11(6): e041186, 2021 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-34172541

RESUMO

INTRODUCTION: People of Ashkenazi Jewish (AJ) ancestry are more likely than unselected populations to have a BRCA1/2 pathogenic variant, which cause a significantly increased risk of breast, ovarian and prostate cancer. Three specific BRCA1/2 pathogenic variants, referred to as BRCA-Jewish founder mutations (B-JFM), account for >90% of BRCA1/2 pathogenic variants in people of AJ ancestry. Current practice of identifying eligible individuals for BRCA testing based on personal and/or family history has been shown to miss at least 50% of people who have one of these variants. Here we describe the protocol of the JeneScreen study-a study established to develop and evaluate two different population-based B-JFM screening programmes, offered to people of Jewish ancestry in Sydney and Melbourne, Australia. METHODS AND ANALYSIS: To rmeasure the acceptability of population-based B-JFM screening in Australia, two screening programmes using different methodologies have been developed. The Sydney JeneScreen programme provides information and obtains informed consent by way of an online tool. The Melbourne JeneScreen programme does this by way of community sessions attended in person. Participants complete questionnaires to measure clinical and psychosocial outcomes at baseline, and for those who have testing, 2 weeks postresult. Participants who decline testing are sent a questionnaire regarding reasons for declining. Participants with a B-JFM are sent questionnaires 12-month and 24-month post-testing. The questionnaires incorporate validated scales, which measure anxiety, decisional conflict and regret, and test-related distress and positive experiences, and other items specifically developed or adapted for the study. These measures will be assessed for each programme and the two population-based B-JFM screening methods will be compared. ETHICS AND DISSEMINATION: Institutional Human Research Ethics Committee approval was obtained from the South Eastern Area Health Service Human Research Ethics Committee: HREC Ref 16/125.Following the analysis of the study results, the findings will be disseminated widely through conferences and publications, and directly to participants in writing.


Assuntos
Neoplasias da Mama , Neoplasias Ovarianas , Neoplasias da Próstata , Austrália , Proteína BRCA1/genética , Proteína BRCA2/genética , Neoplasias da Mama/diagnóstico , Neoplasias da Mama/genética , Predisposição Genética para Doença , Testes Genéticos , Humanos , Judeus/genética , Masculino , Mutação , Neoplasias Ovarianas/diagnóstico , Neoplasias Ovarianas/genética
18.
Cancer Chemother Pharmacol ; 88(1): 39-52, 2021 07.
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.


Assuntos
Neoplasias Colorretais/tratamento farmacológico , Irinotecano/farmacocinética , Irinotecano/uso terapêutico , Adulto , Idoso , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Austrália , Neoplasias Colorretais/genética , Feminino , Genótipo , Humanos , Fígado/efeitos dos fármacos , Masculino , Pessoa de Meia-Idade , Farmacogenética/métodos , Polimorfismo de Nucleotídeo Único/genética , Intervalo Livre de Progressão
19.
NPJ Breast Cancer ; 7(1): 76, 2021 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-34117267

RESUMO

Breast cancer (BC) has a significant heritable component but the genetic contribution remains unresolved in the majority of high-risk BC families. This study aims to investigate the monogenic causes underlying the familial aggregation of BC beyond BRCA1 and BRCA2, including the identification of new predisposing genes. A total of 11,511 non-BRCA familial BC cases and population-matched cancer-free female controls in the BEACCON study were investigated in two sequencing phases: 1303 candidate genes in up to 3892 cases and controls, followed by validation of 145 shortlisted genes in an additional 7619 subjects. The coding regions and exon-intron boundaries of all candidate genes and 14 previously proposed BC genes were sequenced using custom designed sequencing panels. Pedigree and pathology data were analysed to identify genotype-specific associations. The contribution of ATM, PALB2 and CHEK2 to BC predisposition was confirmed, but not RAD50 and NBN. An overall excess of loss-of-function (LoF) (OR 1.27, p = 9.05 × 10-9) and missense (OR 1.27, p = 3.96 × 10-73) variants was observed in the cases for the 145 candidate genes. Leading candidates harbored LoF variants with observed ORs of 2-4 and individually accounted for no more than 0.79% of the cases. New genes proposed by this study include NTHL1, WRN, PARP2, CTH and CDK9. The new candidate BC predisposition genes identified in BEACCON indicate that much of the remaining genetic causes of high-risk BC families are due to genes in which pathogenic variants are both very rare and convey only low to moderate risk.

20.
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.


Assuntos
Fibroma , Neoplasias Ovarianas , Variações do Número de Cópias de DNA , Exoma , Feminino , Fibroma/genética , Humanos , Neoplasias Ovarianas/genética , Trissomia
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