RESUMO
PURPOSE: To determine the genetic predisposition underlying pancreatic acinar cell carcinoma (PACC) and characterize its genomic features. METHODS: Both somatic and germline analyses were performed using an Food and Drug Administration-authorized matched tumor/normal sequencing assay on a clinical cohort of 28,780 patients with cancer, 49 of whom were diagnosed with PACC. For a subset of PACCs, whole-genome sequencing (WGS; n = 12) and RNA sequencing (n = 6) were performed. RESULTS: Eighteen of 49 (36.7%) PACCs harbored germline pathogenic variants in homologous recombination (HR) and DNA damage response (DDR) genes, including BRCA1 (n = 1), BRCA2 (n = 12), PALB2 (n = 2), ATM (n = 2), and CHEK2 (n = 1). Thirty-one PACCs displayed pure, and 18 PACCs harbored mixed acinar cell histology. Fifteen of 31 (48%) pure PACCs harbored a germline pathogenic variant affecting HR-/DDR-related genes. BRCA2 germline pathogenic variants (11 of 31, 35%) were significantly more frequent in pure PACCs than in pancreatic adenocarcinoma (86 of 2,739, 3.1%; P < .001), high-grade serous ovarian carcinoma (67 of 1,318, 5.1%; P < .001), prostate cancer (116 of 3,401, 3.4%; P < .001), and breast cancer (79 of 3,196, 2.5%; P < .001). Genomic features of HR deficiency (HRD) were detected in 7 of 12 PACCs undergoing WGS, including 100% (n = 6) of PACCs with germline HR-related pathogenic mutations and 1 of 6 PACCs lacking known pathogenic alterations in HR-related genes. Exploratory analyses revealed that in PACCs, the repertoire of somatic driver genetic alterations and the load of neoantigens with high binding affinity varied according to the presence of germline pathogenic alterations affecting HR-/DDR-related genes and/or HRD. CONCLUSION: In a large pan-cancer cohort, PACC was identified as the cancer type with the highest prevalence of both BRCA2 germline pathogenic variants and genomic features of HRD, suggesting that PACC should be considered as part of the spectrum of BRCA-related malignancies.
Assuntos
Carcinoma de Células Acinares , Neoplasias Pancreáticas , Masculino , Humanos , Carcinoma de Células Acinares/genética , Neoplasias Pancreáticas/genética , Proteína BRCA2/genética , Proteína BRCA1/genética , Mutação em Linhagem Germinativa , Predisposição Genética para Doença , Recombinação Homóloga , Genômica , Neoplasias PancreáticasRESUMO
Polycystic ovary syndrome (PCOS) is characterized by ovarian enlargement, theca-interstitial hyperplasia, and increased androgen production by theca cells. Previously, our group has demonstrated that statins (competitive inhibitors of 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase, a rate-limiting step of the mevalonate pathway) reduce proliferation of theca-interstitial cells in vitro and decrease serum androgen levels in women with PCOS. The present study evaluated the effect of simvastatin on rat ovarian theca-interstitial cell steroidogenesis. Because actions of statins may be due to reduced cholesterol availability and/or isoprenylation of proteins, the present study also investigated whether steroidogenesis was affected by cell- and mitochondrion-permeable 22-hydroxycholesterol, isoprenylation substrates (farnesyl-pyrophosphate [FPP] and geranylgeranyl-pyrophosphate [GGPP]), as well as selective inhibitors of farnesyltransferase (FTI) and geranylgeranyltransferase (GGTI). Theca-interstitial cells were cultured for 12, 24, and 48 h with or without simvastatin, GGPP, FPP, FTI, GGTI, and/or 22-hydroxycholesterol. Simvastatin decreased androgen levels in a time- and concentration-dependent fashion. This inhibitory effect correlated with a decrease in mRNA levels of Cyp17a1, the gene encoding the key enzyme regulating androgen biosynthesis. After 48 h, GGPP alone and FPP alone had no effect on Cyp17a1 mRNA expression; however, the inhibitory action of simvastatin was partly abrogated by both GGPP and FPP. The present findings indicate that statin-induced reduction of androgen levels is likely due, at least in part, to the inhibition of isoprenylation, resulting in decreased expression of CYP17A1.
Assuntos
Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Ovário/citologia , Sinvastatina/farmacologia , Esteroide 17-alfa-Hidroxilase/antagonistas & inibidores , Esteroide 17-alfa-Hidroxilase/metabolismo , Alquil e Aril Transferases/antagonistas & inibidores , Animais , Células Cultivadas , Farnesiltranstransferase/antagonistas & inibidores , Feminino , Hidroxicolesteróis , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Fosfatos de Poli-Isoprenil/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Reação em Cadeia da Polimerase em Tempo Real , Sesquiterpenos/metabolismo , Esteroide 17-alfa-Hidroxilase/genética , Especificidade por SubstratoRESUMO
BACKGROUND AND OBJECTIVE: Pancreatic ductal adenocarcinoma (PDAC) is characterized by the occurrence of pathogenic variants in BRCA1/2 in 5-6% of patients. Biallelic loss of BRCA1/2 enriches for response to platinum agents and poly (ADP-ribose) polymerase 1 inhibitors. There is a dearth of evidence on the mechanism of inactivation of the wild-type BRCA1 allele in PDAC tumors with a germline BRCA1 (gBRCA1) pathogenic or likely pathogenic variant (P/LPV). Herein, we examine promotor hypermethylation as a "second hit" mechanism in patients with gBRCA1-PDAC. METHODS: We evaluated patients with PDAC who underwent Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets (MSK-IMPACT) somatic and germline testing from an institutional database. DNA isolated from tumor tissue and matched normal peripheral blood were sequenced by MSK-IMPACT. In patients with gBRCA1-PDAC, we examined the somatic BRCA1 mutation status and promotor methylation status of the tumor BRCA1 allele via a methylation array analysis. In patients with sufficient remaining DNA, a second methylation analysis by pyrosequencing was performed. RESULTS: Of 1012 patients with PDAC, 19 (1.9%) were identified to harbor a gBRCA1 P/LPV. Fifteen patients underwent a methylation array and the mean percentage of BRCA1 promotor methylation was 3.62%. In seven patients in whom sufficient DNA was available, subsequent pyrosequencing confirmed an unmethylated BRCA1 promotor. Loss of heterozygosity was detected in 12 of 19 (63%, 95% confidence interval 38-84) patients, demonstrating loss of heterozygosity is the major molecular mechanism of BRCA1 inactivation in PDAC. Two (10.5%) cases had a somatic BRCA1 mutation. CONCLUSIONS: In patients with gBRCA1-P/LPV-PDAC, loss of heterozygosity is the main inactivating mechanism of the wild-type BRCA1 allele in the tumor, and methylation of the BRCA1 promoter is a distinctly uncommon occurrence.
Assuntos
Proteína BRCA1 , Carcinoma Ductal Pancreático , Neoplasias Pancreáticas , Humanos , Proteína BRCA1/genética , Carcinoma Ductal Pancreático/genética , Neoplasias Pancreáticas/genética , Inibidores de Poli(ADP-Ribose) Polimerases , Mutação em Linhagem Germinativa , Metilação de DNA , Regiões Promotoras Genéticas , Neoplasias PancreáticasRESUMO
UNLABELLED: We tested the hypothesis that the pathogenesis of alcoholic liver injury is mediated by epigenetic changes in regulatory genes that result from the induction of aberrant methionine metabolism by ethanol feeding. Five-month-old cystathionine beta synthase heterozygous and wild-type C57BL/6J littermate mice were fed liquid control or ethanol diets by intragastric infusion for 4 weeks. Both ethanol-fed groups showed typical histopathology of alcoholic steatohepatitis, with reduction in liver S-adenosylmethionine (SAM), elevation in liver S-adenosylhomocysteine (SAH), and reduction in the SAM/SAH ratio with interactions of ethanol and genotype effects. Hepatic endoplasmic reticulum stress signals including glucose-regulated protein-78 (GRP78), activating transcription factor 4, growth arrest and DNA damage-inducible gene 153 (GADD153), caspase 12, and transcription factor sterol response element binding protein-1c (SREBP-1c) were up-regulated in ethanol-fed mice with genotype interactions and negative correlations with the SAM/SAH ratio. Immunohistochemical staining showed reduction in trimethylated histone H3 lysine-9 (3meH3K9) protein levels in centrilobular regions in both ethanol groups, with no changes in trimethylated histone H3 lysine-4 levels. The chromatin immunoprecipitation assay revealed a decrease in levels of suppressor chromatin marker 3meH3K9 in the promoter regions of GRP78, SREBP-1c, and GADD153 in ethanol-treated heterozygous cystathionine beta synthase mice. The messenger RNA expression of the histone H3K9 methyltransferase EHMT2 (G9a) was selectively decreased in ethanol-fed mice. CONCLUSION: The pathogenesis of alcoholic steatohepatitis is mediated in part through the effects of altered methionine metabolism on epigenetic regulation of pathways of endoplasmic reticulum stress relating to apoptosis and lipogenesis.
Assuntos
Retículo Endoplasmático/genética , Epigênese Genética , Fígado Gorduroso Alcoólico/etiologia , Homocistinúria/genética , Homocistinúria/metabolismo , Fígado/ultraestrutura , Estresse Fisiológico/genética , Animais , Chaperona BiP do Retículo Endoplasmático , Etanol/administração & dosagem , Fígado Gorduroso Alcoólico/genética , Fígado Gorduroso Alcoólico/metabolismo , CamundongosRESUMO
Polycystic ovary syndrome (PCOS) is characterized by ovarian dysfunction and associated with ovarian theca-interstitial (T-I) cell hyperplasia, hyperinsulinemia, systemic inflammation and oxidative stress. This in vitro study tested whether rat T-I cell growth with or without insulin can be altered by resveratrol, a natural polyphenol with anti-carcinogenic, anti-inflammatory, anti-proliferative and antioxidant properties. Rat T-I cells were cultured with and without resveratrol and/or insulin, and the effects on DNA synthesis, number of viable cells and markers of apoptosis were evaluated. Resveratrol alone induced a potent concentration-dependent inhibition of cell growth by inhibiting DNA synthesis, decreasing the number of viable cells and increasing the activity of executioner caspases 3 and 7; these effects of resveratrol counteracted the pro-proliferative and anti-apoptotic effects of insulin. Immunofluorescence analysis of cells incubated with resveratrol showed concentration- and time-dependent morphological changes consistent with apoptosis. The present findings indicate that resveratrol promotes apoptosis to reduce rat T-I cell growth in vitro as well as inhibiting insulin-induced rat T-I cell growth. This suggests a possibility that resveratrol and/or mechanisms mediating its effect may be relevant to the development of novel treatments for PCOS, which is characterized by both excessive ovarian mesenchyma growth and hyperinsulinemia.
Assuntos
Anticarcinógenos/farmacologia , Apoptose/efeitos dos fármacos , Estilbenos/farmacologia , Células Tecais/citologia , Células Tecais/efeitos dos fármacos , Animais , Caspases/metabolismo , Proliferação de Células/efeitos dos fármacos , Células Cultivadas , Fragmentação do DNA/efeitos dos fármacos , Feminino , Marcação In Situ das Extremidades Cortadas , Ratos , ResveratrolRESUMO
Clinical testing for MLH1 promoter hypermethylation status is important in the workup of patients with MLH1-deficient colorectal and uterine carcinomas when evaluating patients for Lynch syndrome. Current assays use single gene-based methods to assess promoter hypermethylation. Herein, we describe the development and report the performance of a clinical assay for MLH1 promoter hypermethylation using the Infinium methylationEPIC (850k) bead-array platform. Using four cytosine-guanine dinucleotide (CpG) sites within the MLH1 gene promoter, a qualitative MLH1 promoter hypermethylation assay was developed and validated using 63 gastrointestinal and uterine carcinoma samples of known hypermethylation status based on a pyrosequencing reference test. The array-based method achieves clinically robust and reproducible results at an analytical sensitivity level of 8%. Of importance, the 850k array contains probes targeting >850,000 additional CpG sites across the genome, covering sites in most known genes as well as important enhancer regions provided by the Encyclopedia of DNA Elements and Functional Annotation of The Mammalian Genome projects. Thus, the testing modality presented may also be applied to determine the methylation status of other clinically relevant genes or regulatory regions, potentially providing a single laboratory testing workflow for all clinical methylation assays. Furthermore, the concomitant acquisition of genome-wide methylation information provides a workflow that seamlessly enables wider translational epigenetic research.
Assuntos
Metilação de DNA , Epigenômica , Estudo de Associação Genômica Ampla , Sequenciamento de Nucleotídeos em Larga Escala , Proteína 1 Homóloga a MutL/genética , Regiões Promotoras Genéticas , Ilhas de CpG , Epigenômica/métodos , Feminino , Estudo de Associação Genômica Ampla/métodos , Estudo de Associação Genômica Ampla/normas , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Humanos , Masculino , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
Statins are competitive inhibitors of 3-hydroxy-3-methylglutaryl-coenzyme A reductase, a rate-limiting step of the mevalonate pathway. The pleiotropic effects of statins may be due to inhibition of cholesterol synthesis, as well as decreased availability of several biologically important intermediate components of the mevalonate pathway, including two substrates for isoprenylation (farnesyl pyrophosphate [FPP] and geranylgeranyl pyrophosphate [GGPP]). Recently, we demonstrated statin-induced inhibition of ovarian theca-interstitial cell proliferation in vitro, as well as reduction of testosterone levels in women with polycystic ovary syndrome (PCOS). This study evaluates the relative contribution of inhibition of isoprenylation and/or cholesterol availability to the modulation of theca-interstitial proliferation. Rat theca-interstitial cells were cultured in chemically defined media with or without simvastatin, FPP, GGPP, squalene, and/or two membrane-permeable forms of cholesterol (25-hydroxycholesterol and 22-hydroxycholesterol). Simvastatin inhibited DNA synthesis and the count of viable cells. The effects of simvastatin were partly abrogated by FPP and GGPP but not by squalene or cholesterol. Inhibition of farnesyl transferase and geranylgeranyl transferase reduced cell proliferation. The present findings indicate that simvastatin inhibits proliferation of theca-interstitial cells, at least in part, by reduction of isoprenylation. These observations provide likely mechanisms explaining clinically observed improvement of ovarian hyperandrogenism in women with PCOS.
Assuntos
Proliferação de Células/efeitos dos fármacos , Prenilação/fisiologia , Sinvastatina/farmacologia , Células Tecais/efeitos dos fármacos , Análise de Variância , Animais , Contagem de Células , Células Cultivadas , Relação Dose-Resposta a Droga , Feminino , Hidroxicolesteróis/farmacologia , Hipolipemiantes/farmacologia , Fosfatos de Poli-Isoprenil/farmacologia , Prenilação/efeitos dos fármacos , Ratos , Ratos Sprague-Dawley , Sesquiterpenos/farmacologia , Células Tecais/fisiologiaRESUMO
Kinase fusions are rare and poorly characterized in colorectal carcinoma, yet they present unique opportunities for targeted therapy. In this study, we characterized kinase fusions from patients with advanced colorectal carcinoma who had MSK-IMPACT testing of their tumors between January 2014 and June 2018. Patients were analyzed for the presence of fusions, microsatellite instability (MSI), and RAS/BRAF mutations. Mismatch repair (MMR), IHC, and promoter hypermethylation status of MLH1 (MLH1ph) in microsatellite instability-high (MSI-H) colorectal carcinoma with fusions were investigated. Fusion transcripts were confirmed using a targeted RNA-seq panel assay. Of 2,314 colorectal carcinomas with MSK-IMPACT testing, 21 harbored kinase fusions. Overall 57% (12/21) of colorectal carcinoma fusions were MSI-H/MMR-D. Loss of MLH1 and MLH1ph was confirmed in all 12 and all 10 cases with available material, respectively. Fusions were present in 5% of MSI-H/MMR-D colorectal carcinoma compared with 0.4% of MSS/MMR-P colorectal carcinoma (P < 0.001) and 15% of MSI-H/MMR-D colorectal carcinoma with wild-type RAS/BRAF. Of 24 total MLH1-deficient colorectal carcinomas with MLH1ph and wild-type RAS/BRAF, 10 (42%) harbored kinase fusions. Kinase fusions in MSI-H colorectal carcinoma were associated with sporadic MLH1ph rather than with Lynch syndrome, and these patients may be eligible for kinase inhibitors, particularly following resistance or toxicity in response to immunotherapy. These findings identify a molecular subset of colorectal carcinoma with kinase fusions that may be responsive to kinase inhibitors.Significance: A high frequency of targetable kinase fusions in BRAF/RAS wild-type, MSI-H colorectal carcinoma offers a rationale for routine screening to identify patients with colorectal carcinoma with kinase fusions that may be responsive to kinase inhibitors.See related commentary by Valeri, p. 1041.
Assuntos
Biomarcadores Tumorais/análise , Neoplasias Colorretais/genética , Metilação de DNA , Proteína 1 Homóloga a MutL/genética , Proteínas de Fusão Oncogênica/análise , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas p21(ras)/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Neoplasias Colorretais/patologia , Feminino , Seguimentos , Humanos , Masculino , Instabilidade de Microssatélites , Pessoa de Meia-Idade , Mutação , Metástase Neoplásica , Proteínas de Fusão Oncogênica/genética , Prognóstico , Regiões Promotoras GenéticasRESUMO
This article examines the effects of mainstreaming on the attitudes of non-disabled students, in a secondary school, toward people with disabilities. Responses from 389 Form 1 and Form 2 students were analyzed. A 47-item Students' Attitudes toward People with a Disability Scale was used to measure student attitudes at the beginning and end of the school year. The effect of educational intervention and daily classroom contacts on student attitudes was examined. The competitive and achievement orientation of Hong Kong's educational environment poses formidable barriers to the adoption of effective inclusive practices in the classroom. The results of this study indicate that educational intervention outside the classroom has a small effect in changing students' attitudes.
Assuntos
Atitude Frente a Saúde , Deficiências do Desenvolvimento/psicologia , Pessoas com Deficiência/psicologia , Inclusão Escolar , Estudantes/psicologia , Transtorno Autístico/psicologia , Criança , Comportamento Infantil , Feminino , Humanos , Masculino , Grupo Associado , Pessoas com Deficiência Auditiva/psicologia , Comportamento Social , Inquéritos e QuestionáriosRESUMO
Schizophrenia is characterized by heritable deficits in executive function. Two common, functional polymorphisms, catechol-O-methyltransferase (COMT) Val108/158Met and methylenetetrahydrofolate reductase (MTHFR) C677T, have separately been associated with executive function performance in schizophrenia. Given the closely related biochemistry of MTHFR and COMT, it is plausible that the T and Val alleles act synergistically to impair executive function. This investigation of 185 outpatients with schizophrenia examined the interactive effects of these two polymorphisms on Wisconsin Card Sorting Task (WCST) performance. Two WCST measures consistently associated with schizophrenia, perseverative errors and inability to generate categories, were contrasted among compound COMT-MTHFR genotype groups. Individuals homozygous for the COMT Val allele who also carried at least one copy of the MTHFR T allele exhibited a significantly higher percentage of perseverative errors than patients in the other genotype groups. While the T allele also exerted a negative effect on category generation, COMT genotype did not contribute to category performance. It is plausible that cumulative effects of the MTHFR T and COMT Val alleles on intracellular methylation profiles and prefrontal dopamine transmission underlie their interactive effect on perseverative errors.
Assuntos
Catecol O-Metiltransferase/genética , Cognição/fisiologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo de Nucleotídeo Único/fisiologia , Esquizofrenia/fisiopatologia , Adulto , Substituição de Aminoácidos/fisiologia , Metilação de DNA , Dopamina/metabolismo , Epigênese Genética/fisiologia , Feminino , Genótipo , Humanos , Masculino , Metionina/genética , Pessoa de Meia-Idade , Modelos Biológicos , Esquizofrenia/genética , Psicologia do Esquizofrênico , Transmissão Sináptica/genética , Valina/genéticaRESUMO
BACKGROUND: Glutamate carboxypeptidase II (GCPII) encodes for intestinal folate hydrolase and brain N-acetylated alpha-linked acidic dipeptidase. Previous studies provided conflicting results on the effect of the GCPII 1561C-->T polymorphism on folate and total homocysteine (tHcy) concentrations. OBJECTIVE: We aimed to determine the potential effects of 2 polymorphisms of GCPII on plasma folate and tHcy concentrations, cognition, anxiety, and depression in a large aging cohort of Norwegians enrolled in the Hordaland Homocysteine Study. DESIGN: DNA samples were genotyped for the GCPII 1561C-->T and 484A-->G polymorphisms, and the results were linked to plasma folate and tHcy concentrations and to scores for cognition, anxiety, and depression. RESULTS: The 2 polymorphisms were in linkage disequilibrium and were associated with concentrations of tHcy. After adjustment for covariates, persons in the CT or combined CT and TT groups of the 1561C-->T polymorphism had higher plasma folate concentrations and lower tHcy concentrations than did those in the CC group. Subjects with the TT genotype had lower Symbol Digit Modalities Test (SDMT) scores than did subjects with the CC genotype. Compared with abstainers, moderate alcohol drinkers had higher plasma folate concentrations and higher scores on the Mini Mental State Examination. However, women abstainers with the CT genotype had lower SDMT scores than did abstainers with the CC genotype or moderate drinkers with the CT genotype. CONCLUSIONS: The 1561C-->T polymorphism is associated with higher plasma folate and lower tHcy concentrations and with lower SDMT cognitive scores in women who abstain from alcohol.
Assuntos
Antígenos de Superfície/genética , Ansiedade/genética , Cognição/fisiologia , Depressão/genética , Ácido Fólico/sangue , Glutamato Carboxipeptidase II/genética , Homocisteína/sangue , Polimorfismo Genético , Consumo de Bebidas Alcoólicas/epidemiologia , Animais , Doenças Cardiovasculares/epidemiologia , DNA/genética , Primers do DNA , Éxons , Feminino , Genótipo , Humanos , Desequilíbrio de Ligação , Masculino , Noruega , TemperançaRESUMO
BACKGROUND: The methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism has been associated with both overall schizophrenia risk and severity of negative symptoms. This study examined whether schizophrenia patients homozygous for the risk allele (T/T) exhibit greater impairment in executive function, and determined the extent to which MTHFR's effects on negative symptoms underlie this relationship. METHODS: 200 outpatients with chronic schizophrenia were evaluated with the Verbal Fluency Test (VFT), Wisconsin Card Sort Test (WCST), and California Verbal Learning Test (CVLT). Performance was stratified by MTHFR C667T genotype. Path analysis determined the extent to which MTHFR effects on negative symptoms mediated the relationship between genotype and cognitive measures. RESULTS: T/T subjects exhibited significantly greater deficits on the VFT and had more difficulty achieving the first category on the WCST. Genotype groups did not differ in CVLT performance. C677T effects on negative symptoms contributed to, but did not fully account for, genotype effects on VFT. Negative symptoms did not mediate WCST performance. CONCLUSIONS: MTHFR C677T genotype contributes to certain executive function deficits in schizophrenia. These deficits remained significant when taking into account mediating effects of negative symptoms. Although the intermediate mechanisms for C677T effects remain uncertain, these results suggest that MTHFR-related cognitive impairment and negative symptoms reflect differing neural substrates.
Assuntos
Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Metilenotetra-Hidrofolato Redutase (NADPH2)/genética , Polimorfismo Genético/genética , Esquizofrenia/epidemiologia , Esquizofrenia/genética , Adulto , Afeto , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Índice de Gravidade de Doença , Comportamento Verbal , Aprendizagem VerbalRESUMO
PURPOSE: Microsatellite instability (MSI)/mismatch repair (MMR) status is increasingly important in the management of patients with cancer to predict response to immune checkpoint inhibitors. We determined MSI status from large-panel clinical targeted next-generation sequencing (NGS) data across various solid cancer types. METHODS: The MSI statuses of 12,288 advanced solid cancers consecutively sequenced with Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets clinical NGS assay were inferred by using MSIsensor, a program that reports the percentage of unstable microsatellites as a score. Cutoff score determination and sensitivity/specificity were based on MSI polymerase chain reaction (PCR) and MMR immunohistochemistry. RESULTS: By using an MSIsensor score ≥ 10 to define MSI high (MSI-H), 83 (8%) of 996 colorectal cancers (CRCs) and 42 (16%) of 260 uterine endometrioid cancers (UECs) were MSI-H. Validation against MSI PCR and/or MMR immunohistochemistry performed for 138 (24 MSI-H, 114 microsatellite stable [MSS]) CRCs, and 40 (15 MSI-H, 25 MSS) UECs showed a concordance of 99.4%. MSIsensor also identified 68 MSI-H/MMR-deficient (MMR-D) non-CRC/UECs. Of 9,591 non-CRC/UEC tumors with MSS MSIsensor status, 456 (4.8%) had slightly elevated scores(≥3 and <10) of which 96.6% with available material were confirmed to be MSS by MSI PCR. MSI-H was also detected and confirmed in three non-CRC/UECs with low exonic mutation burden (< 20). MSIsensor correctly scored all 15 polymerase ε ultra-mutated cancers as negative for MSI. CONCLUSION: MSI status can be reliably inferred by MSIsensor from large-panel targeted NGS data. Concurrent MSI testing by NGS is resource efficient, is potentially more sensitive for MMR-D than MSI PCR, and allows identification of MSI-H across various cancers not typically screened, as highlighted by the finding that 35% (68 of 193) of all MSI-H tumors were non-CRC/ UEC.
RESUMO
BACKGROUND: The growing number of Next Generation Sequencing (NGS) tests is transforming the routine clinical diagnosis of hereditary cancers. Identifying whether a cancer is the result of an underlying disease-causing mutation in a cancer predisposition gene is not only diagnostic for a cancer predisposition syndrome, but also has significant clinical implications in the clinical management of patients and their families. METHODS: Here, we evaluated the performance of MSK-IMPACT (Memorial Sloan Kettering-Integrated Mutation Profiling of Actionable Cancer Targets) in detecting genetic alterations in 76 genes implicated in cancer predisposition syndromes. Output from hybridization-based capture was sequenced on an Illumina HiSeq 2500. A custom analysis pipeline was used to detect single nucleotide variants (SNVs), small insertions/deletions (indels) and copy number variants (CNVs). RESULTS: MSK-IMPACT detected all germline variants in a set of 233 unique patient DNA samples, previously confirmed by previous single gene testing. Reproducibility of variant calls was demonstrated using inter- and intra- run replicates. Moreover, in 16 samples, we identified additional pathogenic mutations other than those previously identified through a traditional gene-by-gene approach, including founder mutations in BRCA1, BRCA2, CHEK2 and APC, and truncating mutations in TP53, TSC2, ATM and VHL. CONCLUSIONS: This study highlights the importance of the NGS-based gene panel testing approach in comprehensively identifying germline variants contributing to cancer predisposition and simultaneous detection of somatic and germline alterations.
Assuntos
Análise Mutacional de DNA/métodos , Predisposição Genética para Doença , Mutação em Linhagem Germinativa , Proteínas de Neoplasias/genética , Neoplasias/metabolismo , Proteína da Polipose Adenomatosa do Colo/genética , Proteínas Mutadas de Ataxia Telangiectasia/genética , Proteína BRCA1/genética , Proteína BRCA2/genética , Biomarcadores Tumorais/genética , Quinase do Ponto de Checagem 2/genética , Variações do Número de Cópias de DNA , Humanos , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Reprodutibilidade dos Testes , Proteína 2 do Complexo Esclerose Tuberosa , Proteína Supressora de Tumor p53/genética , Proteínas Supressoras de Tumor/genética , Proteína Supressora de Tumor Von Hippel-Lindau/genéticaRESUMO
The self-help movement in Hong Kong has been gradually gaining its momentum in recent years. The primary purpose of the research was to give voice to the experiences and views of patients towards cancer care and to influence healthcare providers and policy makers to act on patients' agendas. Self-help groups and their members are mobilized through the research activities of focus groups, interviews and a patient forum to specify and act on their needs. This article describes the project and the participatory action research (PAR) strategies in the mobilization of, and collaboration with, patient groups in research design, data analysis, and dissemination of findings. The implications on healthcare practice, particularly within an era of reform and restructuring of the healthcare system, are discussed.
Assuntos
Serviços de Saúde Comunitária , Continuidade da Assistência ao Paciente , Neoplasias/reabilitação , Satisfação do Paciente , Grupos de Autoajuda , Serviços de Saúde Comunitária/organização & administração , Pesquisa sobre Serviços de Saúde/métodos , Hong Kong , Humanos , SobreviventesRESUMO
Previous studies showed that cigarette smoking was closely associated with gastric ulceration. People usually smoke under stress conditions, and together, these could induce more gastric damage. In the present study, we aimed to study the effects of nicotine administration and its withdrawal on stress-induced gastric ulceration in rats. Male Sprague-Dawley rats were given nicotine (25 or 50 microg/ml) for 10 days and then withdrawn for 2, 4 or 6 days. They were subjected to cold-restraint stress for 2 h after nicotine treatment or after nicotine withdrawal, and then killed. The results indicated that both nicotine treatment and its withdrawal potentiated stress-induced gastric damage. The mucosal glutathione (GSH) and mucus levels were reduced by stress and decreased further by nicotine. The prostaglandin E(2) concentration remained unchanged. To conclude, the adverse effect of nicotine on stress ulceration was prostaglandin E(2)-independent but mediated by the depression of glutathione and mucus levels in the gastric mucosa.
Assuntos
Nicotina/toxicidade , Úlcera Gástrica/etiologia , Estresse Fisiológico/complicações , Animais , Dinoprostona/análise , Dinoprostona/fisiologia , Feminino , Mucosa Gástrica/química , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/patologia , Glutationa/análise , Ratos , Ratos Sprague-DawleyRESUMO
This paper reports the results of a qualitative study that examined the experiences of cancer patients with the intention of incorporating consumer perspectives into the development of quality cancer care in Hong Kong. Altogether, eight focus group interviews were conducted with a total of 41 cancer patients. The results indicate that patients lack clear guidance and support regarding the management of sequelae and surveillance against recurrence. Patients also raised concerns about the lack of access to information, and the lack of health care provider accountability. Any understanding of the scope and goals of follow-up cancer care is obscured when the healthcare environment is not conducive to good doctor-patient communication. Patients are calling for more explicit goals and clinical practice guidelines to serve as frames of reference for both patients and doctors.
Assuntos
Assistência ao Convalescente/normas , Neoplasias/terapia , Satisfação do Paciente , Assistência ao Convalescente/psicologia , Comunicação , Feminino , Grupos Focais , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/psicologia , Educação de Pacientes como Assunto , Relações Médico-Paciente , Recidiva , Inquéritos e Questionários , Resultado do TratamentoRESUMO
BACKGROUND: Polycystic ovary syndrome (PCOS) is characterized by ovarian enlargement, hyperplastic theca compartment and increased androgen production due to, at least in part, excessive expression of several key genes involved in steroidogenesis. Previously, our group has demonstrated that simvastatin, competitive inhibitor of 3-hydroxy-3-methyl-glutaryl-CoA reductase (HMG-CoA reductase), a rate-limiting step of the mevalonate pathway, reduces rat-theca interstitial cell steroidogenesis by inhibiting Cyp17a1 gene expression, the key enzyme of the androgen biosynthesis pathway. Recently, we demonstrated that resveratrol, a bioflavonoid abundant in red grapes, decreases rat theca-interstitial cell steroidogenesis and this suppressive effect is mediated through mechanisms independent of the mevalonate pathway. The present study evaluated the effect of combining simvastatin and resveratrol treatments on rat theca-interstitial cell steroidogenesis. METHODS: Rat theca-interstitial cells isolated from 30 day-old female rats were cultured for up to 48 h with or without simvastatin (1 µM) and/or resveratrol (3-10 µM). Steroidogenic enzymes gene expression was evaluated by quantitative real time PCR and steroid levels were measured by liquid chromatography-mass spectrometry. Comparisons between groups were performed using ANOVA and Tukey test. RESULTS: Resveratrol potentiated inhibitory effects of simvastatin on androstenedione and androsterone production in theca-interstitial cells. This suppressive effect correlated with profound inhibition in Cyp17a1 mRNA expression in the presence of a combination of resveratrol and simvastatin. CONCLUSIONS: The present findings indicate that resveratrol potentiates the simvastatin-induced inhibitory effect on theca-interstitial cell androgen production, raising the possibility of development of novel treatments of PCOS.
Assuntos
Androstenodiona/biossíntese , Androsterona/biossíntese , Inibidores de Hidroximetilglutaril-CoA Redutases/farmacologia , Sinvastatina/farmacologia , Estilbenos/farmacologia , Células Tecais/efeitos dos fármacos , Animais , Células Cultivadas , Relação Dose-Resposta a Droga , Regulação para Baixo , Sinergismo Farmacológico , Feminino , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , RNA Mensageiro/metabolismo , Ratos Sprague-Dawley , Resveratrol , Esteroide 17-alfa-Hidroxilase/genética , Esteroide 17-alfa-Hidroxilase/metabolismo , Células Tecais/enzimologia , Fatores de TempoRESUMO
OBJECTIVE: To evaluate the effects of letrozole on ovarian size and steroidogenesis in vivo, as well as on proliferation and steroidogenesis of theca-interstitial cells alone and in coculture with granulosa cells using an in vitro model. DESIGN: In vivo and in vitro studies. SETTING: Research laboratory. ANIMAL(S): Immature Sprague-Dawley female rats. INTERVENTION(S): In vivo effects of letrozole were studied in intact rats receiving either letrozole (90-day continuous-release SC pellets, 400 µg/d) or placebo pellets (control group). In in vitro experiments, theca cells were cultured alone or in coculture with granulosa cells in the absence or presence of letrozole. MAIN OUTCOME MEASURE(S): Deoxyribonucleic acid synthesis was determined by thymidine incorporation assay; steroidogenesis by mass spectrometry; and steroidogenic enzyme messenger RNA (mRNA) expression by polymerase chain reaction. RESULT(S): In vivo, letrozole induced an increase in ovarian size compared with the control group and also induced a profound increase of androgen, LH levels, and Cyp17a1 mRNA expression. Conversely, a decrease in Star, Cyp11a1, and Hsd3b1 transcripts was observed in letrozole-exposed rats. In vitro, letrozole did not alter either theca cell proliferation or Cyp17a1 mRNA expression. Similarly, letrozole did not affect Cyp17a1 transcripts in granulosa-theca cocultures. CONCLUSION(S): These findings suggest that letrozole exerts potent, but indirect, effect on growth of rat ovary and dramatically increases androgen levels and Cyp17a1 mRNA expression, the key enzyme regulating the androgen biosynthesis pathway. The present findings reveal novel mechanisms of action of letrozole in the rat ovary.