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1.
Ann Oncol ; 35(2): 183-189, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37992871

RESUMO

BACKGROUND: Predicting relapse and overall survival (OS) in early-stage non-small-cell lung cancer (NSCLC) patients remains challenging. Therefore, we hypothesized that detection of circulating tumor DNA (ctDNA) can identify patients with increased risk of relapse and that integrating radiological tumor volume measurement along with ctDNA detectability improves prediction of outcome. PATIENTS AND METHODS: We analyzed 366 serial plasma samples from 85 patients who underwent surgical resections and assessed ctDNA using a next-generation sequencing liquid biopsy assay, and measured tumor volume using a computed tomography-based three-dimensional annotation. RESULTS: Our results showed that patients with detectable ctDNA at baseline or after treatment and patients who did not clear ctDNA after treatment had a significantly worse clinical outcome. Integrating radiological analysis allowed the stratification in risk groups prognostic of clinical outcome as confirmed in an independent cohort of 32 patients. CONCLUSIONS: Our findings suggest ctDNA and radiological monitoring could be valuable tools for guiding follow-up care and treatment decisions for early-stage NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas , DNA Tumoral Circulante , Neoplasias Pulmonares , Carcinoma de Pequenas Células do Pulmão , Humanos , DNA Tumoral Circulante/genética , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/cirurgia , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/cirurgia , Carga Tumoral , Mutação , Recidiva , Biomarcadores Tumorais/genética
2.
ESMO Open ; 9(1): 102199, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38071928

RESUMO

BACKGROUND: Brain metastasis (BRM) is uncommon in gastroesophageal cancer. As such, clinicopathologic and molecular determinants of BRM and impact on clinical outcome remain incompletely understood. METHODS: We retrospectively analyzed clinicopathologic data from advanced esophageal/gastroesophageal junction (E/GEJ) patients at Johns Hopkins from 2003 to 2021. We investigated the association between several clinical and molecular features and the occurrence of BRM, with particular focus on human epidermal growth factor receptor 2 (HER2) overexpression. Survival outcomes and time to BRM onset were also evaluated. RESULTS: We included 515 patients with advanced E/GEJ cancer. Tumors were 78.3% esophageal primary, 82.9% adenocarcinoma, 31.0% HER2 positive. Cumulative incidence of BRM in the overall cohort and within HER2+ subgroup was 13.8% and 24.3%, respectively. HER2 overexpression was associated with increased risk of BRM [odds ratio 2.45; 95% confidence interval (CI) 1.10-5.46]. On initial presentation with BRM, 50.7% had a solitary brain lesion and 11.3% were asymptomatic. HER2+ status was associated with longer median time to onset of BRM (14.0 versus 6.3 months, P < 0.01), improved median progression free survival on first-line systemic therapy (hazard ratio 0.35, 95% CI 0.16-0.80), and improved median overall survival (hazard ratio 0.20, 95% CI 0.08-0.54) in patients with BRM. CONCLUSION: HER2 overexpression identifies a gastroesophageal cancer molecular subtype that is significantly associated with increased risk of BRM, though with later onset of BRM and improved survival likely reflecting the impact of central nervous system-penetrant HER2-directed therapy. The prevalence of asymptomatic and solitary brain lesions suggests that brain surveillance for HER2+ patients warrants prospective investigation.


Assuntos
Adenocarcinoma , Neoplasias Encefálicas , Neoplasias Esofágicas , Neoplasias Gástricas , Humanos , Estudos Retrospectivos , Estudos Prospectivos , Neoplasias Esofágicas/patologia , Junção Esofagogástrica/metabolismo , Junção Esofagogástrica/patologia
3.
Prev Med Rep ; 23: 101397, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-34040933

RESUMO

Based on the results of randomized control trials, screening for lung cancer using computed tomography (CT) is now widely recommended. However, adherence to screening remains an issue outside the clinical trial setting. This study examines the utility of biomarker-based risk assessment on uptake and subsequent adherence in a community screening study. In a single arm pilot study, current or former smokers > 50 years old with 20 + pack year history were recruited following local advertising. One hundred and fifty seven participants volunteered to participate in the study that offered an optional gene-based lung cancer risk assessment followed by low-dose CT according to a standardised screening protocol. All 157 volunteers who attended visit 1 underwent the gene-based risk assessment comprising of a clinical questionnaire and buccal swab. Of this group, 154 subsequently attended for CT screening (98%) and were followed prospectively for a median of 2.7 years. A participant's adherence to screening was influenced by their baseline lung cancer risk category, with overall adherence in those with a positive scan being significantly greater in the "very high" risk group compared to "moderate" and "high" risk categories (71% vs 52%, Odds ratio = 2.27, 95% confidence interval of 1.02-5.05, P = 0.047). Those in the "moderate" risk group were not different to those in the "high" risk group (52% and 52%, P > 0.05). In this proof-of-concept study, personalised gene-based lung cancer risk assessment was well accepted, associated with a 98% uptake for screening and increased adherence for those in the highest risk group.

4.
Ann Bot ; 124(5): 791-807, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31346602

RESUMO

BACKGROUND AND AIMS: Fully mycoheterotrophic plants derive carbon and other nutrients from root-associated fungi and have lost the ability to photosynthesize. While mycoheterotroph plastomes are often degraded compared with green plants, the effect of this unusual symbiosis on mitochondrial genome evolution is unknown. By providing the first complete organelle genome data from Polygalaceae, one of only three eudicot families that developed mycoheterotrophy, we explore how both organellar genomes evolved after loss of photosynthesis. METHODS: We sequenced and assembled four complete plastid genomes and a mitochondrial genome from species of Polygalaceae, focusing on non-photosynthetic Epirixanthes. We compared these genomes with those of other mycoheterotroph and parasitic plant lineages, and assessed whether organelle genes in Epirixanthes experienced relaxed or intensified selection compared with autotrophic relatives. KEY RESULTS: Plastomes of two species of Epirixanthes have become substantially degraded compared with that of autotrophic Polygala. Although the lack of photosynthesis is presumably homologous in the genus, the surveyed Epirixanthes species have marked differences in terms of plastome size, structural rearrangements, gene content and substitution rates. Remarkably, both apparently replaced a canonical plastid inverted repeat with large directly repeated sequences. The mitogenome of E. elongata incorporated a considerable number of fossilized plastid genes, by intracellular transfer from an ancestor with a less degraded plastome. Both plastid and mitochondrial genes in E. elongata have increased substitution rates, but the plastid genes of E. pallida do not. Despite this, both species have similar selection patterns operating on plastid housekeeping genes. CONCLUSIONS: Plastome evolution largely fits with patterns of gene degradation seen in other heterotrophic plants, but includes highly unusual directly duplicated regions. The causes of rate elevation in the sequenced Epirixanthes mitogenome and of rate differences in plastomes of related mycoheterotrophic species are not currently understood.


Assuntos
Genoma Mitocondrial , Genomas de Plastídeos , Magnoliopsida , Polygalaceae , Evolução Molecular , Processos Heterotróficos , Filogenia
5.
Diabetes Res Clin Pract ; 103(2): 328-37, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24468095

RESUMO

BACKGROUND: Diabetes is associated with an increased risk of cancer. This study aimed to evaluate associations between recently reported type 2 diabetes (T2D) susceptibility genetic variants and cancer risk in a prospective cohort of Chinese patients with T2D. METHODS: Seven single nucleotide polymorphisms (SNP) in IGF2BP2, CDKAL1, SLC30A8, CDKN2A/B, HHEX and TCF7L2, all identified from genome-wide association studies of T2D, were genotyped in 5900 T2D patients [age mean ± SD = 57 ± 13 years, % males = 46] without any known cancer at baseline. Associations between new-onset of cancer and SNPs were tested by Cox proportional hazard models with adjustment of conventional risk factors. RESULTS: During the mean follow-up period of 8.5 ± 3.3 years, 429 patients (7.3%) developed cancer. Of the T2D-related SNPs, the G-alleles of HHEX rs7923837 (hazard ratio [HR] (95% C.I.) = 1.34 (1.08-1.65); P = 6.7 ×10(-3) under dominant model) and TCF7L2 rs290481 (HR (95% C.I.) = 1.16 (1.01-1.33); P = 0.040 under additive model) were positively associated with cancer risk, while the G-allele of CDKAL1 rs7756992 was inversely associated (HR (95% C.I.) = 0.80 (0.65-1.00); P = 0.048 under recessive model). The risk alleles of these significant SNPs exhibited combined effect on increasing cancer risk (per-allele HR (95% C.I.) = 1.25 (1.12-1.39); P = 4.8 × 10(-5)). The adjusted cancer risk was 2.41 (95% C.I. 1.23-4.69) for patients with four risk alleles comparing to patients without risk allele. CONCLUSIONS: T2D-related variants HHEX rs7923837, TCF7L2 rs290481 and CDKAL1 rs7756992 increased cancer risk in patients with diabetes. IMPACT: Our findings provide novel insights into the pathogenesis of cancer in diabetes.


Assuntos
Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Genótipo , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Adulto , Idoso , Alelos , Povo Asiático/genética , China , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Estudo de Associação Genômica Ampla , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Neoplasias/epidemiologia , Estudos Prospectivos
6.
Diabetologia ; 56(6): 1291-305, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23532257

RESUMO

AIMS/HYPOTHESIS: Most genetic variants identified for type 2 diabetes have been discovered in European populations. We performed genome-wide association studies (GWAS) in a Chinese population with the aim of identifying novel variants for type 2 diabetes in Asians. METHODS: We performed a meta-analysis of three GWAS comprising 684 patients with type 2 diabetes and 955 controls of Southern Han Chinese descent. We followed up the top signals in two independent Southern Han Chinese cohorts (totalling 10,383 cases and 6,974 controls), and performed in silico replication in multiple populations. RESULTS: We identified CDKN2A/B and four novel type 2 diabetes association signals with p < 1 × 10(-5) from the meta-analysis. Thirteen variants within these four loci were followed up in two independent Chinese cohorts, and rs10229583 at 7q32 was found to be associated with type 2 diabetes in a combined analysis of 11,067 cases and 7,929 controls (p meta = 2.6 × 10(-8); OR [95% CI] 1.18 [1.11, 1.25]). In silico replication revealed consistent associations across multiethnic groups, including five East Asian populations (p meta = 2.3 × 10(-10)) and a population of European descent (p = 8.6 × 10(-3)). The rs10229583 risk variant was associated with elevated fasting plasma glucose, impaired beta cell function in controls, and an earlier age at diagnosis for the cases. The novel variant lies within an islet-selective cluster of open regulatory elements. There was significant heterogeneity of effect between Han Chinese and individuals of European descent, Malaysians and Indians. CONCLUSIONS/INTERPRETATION: Our study identifies rs10229583 near PAX4 as a novel locus for type 2 diabetes in Chinese and other populations and provides new insights into the pathogenesis of type 2 diabetes.


Assuntos
Cromossomos Humanos Par 7 , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , Proteínas de Homeodomínio/genética , Fatores de Transcrição Box Pareados/genética , Adulto , Idoso , Povo Asiático , China , Diabetes Mellitus Tipo 2/etnologia , Feminino , Marcadores Genéticos , Variação Genética , Genótipo , Hong Kong , Humanos , Células Secretoras de Insulina/citologia , Japão , Masculino , Pessoa de Meia-Idade , Singapura
7.
Diabet Med ; 27(12): 1443-9, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21059098

RESUMO

AIMS: POU class 2 homeobox 1 (POU2F1), also known as octamer-binding transcription factor-1 (OCT-1), is a ubiquitous transcription factor that plays a key role in the regulation of genes related to inflammation and cell cycles. POU2F1 is located on chromosome 1q24, a region with linkage for Type 2 diabetes in Chinese and other populations. We examined the association of POU2F1 genetic variants with Type 2 diabetes in Hong Kong Chinese using two independent cohorts. METHODS: We genotyped five haplotype-tagging single nucleotide polymorphisms at POU2F1 in 1378 clinic-based patients with Type 2 diabetes and 601 control subjects, as well as 707 members from 179 families with diabetes. RESULTS: We found significant associations of rs4657652, rs7532692, rs10918682 and rs3767434 (OR = 1.26-1.59, 0.0003 < P(unadjusted) < 0.035) with Type 2 diabetes in the clinic-based case-control cohorts. Rs3767434 was also associated with Type 2 diabetes (OR = 1.55, P(unadjusted) = 0.013) in the family-based cohort. Meta-analysis revealed similar associations. In addition, the risk G allele of rs10918682 showed increased usage of insulin treatment during a mean follow-up period of 7 years [hazard ratio = 1.50 (1.05-2.14), P = 0.025]. CONCLUSIONS: Using separate cohorts, we observed consistent results showing the contribution of multiple variants at POU2F1 to the risk of Type 2 diabetes.


Assuntos
Povo Asiático/genética , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Fator 1 de Transcrição de Octâmero/genética , Polimorfismo de Nucleotídeo Único , Adulto , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Ligação Genética/genética , Genótipo , Hong Kong/epidemiologia , Humanos , Masculino , Pessoa de Meia-Idade , Filogenia , Fatores de Risco , Fatores de Transcrição/genética
9.
J Clin Neurophysiol ; 25(4): 218-21, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18677186

RESUMO

Multiple sleep latency test (MSLT) remains the golden standard for the clinical diagnosis and management of excessive daytime sleepiness. However, there was limited data on the reliability measurement of MSLT. Forty-four (M/F ratio: 26/18, mean age of 43.4 +/- 13.9 years) subjects of an ongoing family study of narcolepsy underwent a standard polysomnogram and MSLT. Three trained staff of various level of experiences independently and blindly scored each nap (n = 219). To test for intrarater reliability, 100 naps (n = 20 subjects) were re-scored half a year later. The interrater reliability for the mean sleep latency of 5 naps, sleep latency, and rapid eye movement (REM) sleep latency of individual nap, presence and numbers of sleep onset REM periods varied from the range of 0.668 to 0.964. The mean interrater reliability for the clinical diagnosis of narcolepsy was 0.883 (range, 0.824-0.938), whereas it was 0.750 (range, 0.674-0.858) for the diagnosis of narcolepsy spectrum disorder (shortened mean sleep latency and/or the presence of sleep onset REM periods) and 0.796 (range, 0.697-0.846) for normal cases. The intrarater reliability for the sleep latency and sleep onset REM periods varied from the range of 0.625 to 0.991. Our study demonstrated excellent inter- and intrarater reliability in scoring the sleep latency and sleep onset REM periods of MSLT. They also had excellent agreement on the diagnosis of narcolepsy and an "excellent to good" agreement on the diagnosis of narcolepsy spectrum disorder and normal cases. Our study lent further support that MSLT was an objective measurement with high inter- and intrarater reliability across various sleep disorders and healthy controls among different sleep centers.


Assuntos
Narcolepsia/diagnóstico , Polissonografia/métodos , Adulto , Feminino , Humanos , Masculino , Variações Dependentes do Observador , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego
10.
Clin Genet ; 70(1): 20-8, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16813599

RESUMO

Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. In DN patients, triglyceride (TG) level is elevated and lipoprotein lipase (LPL) activity, which hydrolyzes TG, is decreased. The LPL S447X and apolipoprotein E (APOE) exon 4 polymorphisms affect TG levels, and the APOC3 -455T>C polymorphism affects LPL activity. Our aim was to examine the association of these polymorphisms with nephropathy in type 2 diabetes. We examined these polymorphisms in a case-control study of type 2 diabetic patients including 374 with DN and 392 without DN. LPL 447X-containing genotypes (447X+) were significantly decreased in DN patients [18.6 vs 25.6%, odds ratio (OR) = 0.66, p = 0.02], as were APOE epsilon3/epsilon3 genotypes (64.8 vs 73.1%, OR = 0.68, p = 0.01). In addition, combinations of genotypes [APOE epsilon3/epsilon3 and LPL 447X+ (OR = 0.56), APOC3 CC and LPL 447X+ (OR = 0.31), APOE epsilon3/epsilon3 and APOC3 CC (OR = 0.61] were protective for DN compared with the most common combination of the respective polymorphisms. Our findings suggest the importance of interactions among lipid genes in modulating the risk of DN.


Assuntos
Apolipoproteínas C/genética , Apolipoproteínas E/genética , Neuropatias Diabéticas/genética , Neuropatias Diabéticas/metabolismo , Lipase Lipoproteica/genética , Idoso , Apolipoproteína C-III , Estudos de Casos e Controles , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/metabolismo , Neuropatias Diabéticas/etiologia , Éxons , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Fatores de Risco
11.
Diabetologia ; 48(10): 2018-24, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16132950

RESUMO

AIMS/HYPOTHESIS: The transcription factor upstream stimulatory factor 1 (USF1) regulates the expression of genes involved in glucose and lipid metabolism and has been associated with familial combined hyperlipidaemia. USF1 is located on chromosome 1q22-23, a region with evidence for linkage to type 2 diabetes and various traits of the metabolic syndrome in Chinese and other populations. The aim of this study was to investigate the linkage and association of USF1 with type 2 diabetes and the metabolic syndrome in Chinese individuals. MATERIALS AND METHODS: We genotyped three haplotype-tagging single nucleotide polymorphisms (SNPs) (rs3737787, rs2516841 and rs2516839) at USF1 in three samples of the Hong Kong Chinese population, including members of 179 families from the Hong Kong Family Diabetes Study, 1,383 hospital cases with type 2 diabetes and/or the metabolic syndrome and 454 normal control subjects. RESULTS: We found significant association of individual polymorphisms and haplotypes with type 2 diabetes and/or metabolic syndrome-related traits in the family samples using either family-based or unrelated normal control subjects. However, these variants could not explain much of the evidence for linkage in this region. Moreover, they were not associated with type 2 diabetes and/or the metabolic syndrome in the hospital cases. CONCLUSIONS/INTERPRETATION: The results are consistent with the hypothesis that variation at USF1 contributes to the risk of type 2 diabetes and the metabolic syndrome in families with strong evidence for linkage in the chromosome 1q region. However, they provide little support for USF1 as the susceptibility locus that generates the observed evidence for linkage at 1q21-25 for type 2 diabetes and/or the metabolic syndrome, and USF1 does not appear to have a major contribution to these phenotypes in the general Chinese population.


Assuntos
Diabetes Mellitus Tipo 2/genética , Síndrome Metabólica/genética , Fatores Estimuladores Upstream/genética , Adulto , Estudos de Casos e Controles , China/epidemiologia , Interpretação Estatística de Dados , Diabetes Mellitus Tipo 2/epidemiologia , Feminino , Ligação Genética , Genótipo , Haplótipos , Humanos , Desequilíbrio de Ligação , Masculino , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único
12.
J Neural Transm (Vienna) ; 108(6): 671-7, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11478419

RESUMO

Epidemiological studies have shown a lower prevalence of tardive dyskinesia (TD) among Chinese psychiatric patients compared to Caucasian and Black patient populations. It has been hypothesized that pharmacogenetic factors may underlie this cross-cultural difference. Due to the important implications of the dopamine D3 receptor gene (DRD3) in motor control, we investigated the frequency of polymorphic serine (ser) to glycine (gly) substitution of the gene DRD3 in Chinese schizophrenic patients. The sample size consisted of 65 patients with TD and 66 without TD. Patients were assessed for the severity of TD, the presence of akathisia and parkinsonian symptoms and were subsequently genotyped. We found no evidence that the dopamine D3 receptor gene is likely to confer susceptibility to the development of tardive dyskinesia in Chinese patients with schizophrenia.


Assuntos
Discinesia Induzida por Medicamentos/genética , Receptores de Dopamina D2/genética , Esquizofrenia/genética , Adulto , Idoso , Antipsicóticos/efeitos adversos , Povo Asiático/genética , Feminino , Genótipo , Hong Kong , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Receptores de Dopamina D3 , Esquizofrenia/tratamento farmacológico
13.
Pharmacopsychiatry ; 34(6): 238-41, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11778144

RESUMO

BACKGROUND: The discovery of Cytochrome P450 2D6 (CYP 2D6) polymorphism is implicated in individual differences in drug metabolism rate. Mutation with defective alleles is associated with reduced metabolism of many anti-psychotic drugs metabolized by CYP 2D6. This may contribute to the development of tardive dyskinesia (TD) in patients with prolonged exposure to anti-psychotic drugs. METHODS: In this controlled study, the genotype of CYP 2D6*10 alleles, movement disorders and clinical characteristics in 38 Chinese schizophrenic patients with TD were compared with 38 age- and sex-matched schizophrenia patients without TD. RESULTS: There was no significant correlation between CYP 2D6*10 genotypes and TD in men. However, a significant increase in the frequency of CYP 2D6*10 allele was found in female patients with TD. CONCLUSIONS: The sex differences in CYP 2D6 genotyping and vulnerability to develop TD suggest that a biological predisposition that affects pharmacokinetics may be more significant in women, whereas other factors may be more important in men.


Assuntos
Citocromo P-450 CYP2D6/genética , Discinesia Induzida por Medicamentos/genética , Esquizofrenia/genética , Adulto , Antipsicóticos/efeitos adversos , Povo Asiático , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade , Polimorfismo Genético , Esquizofrenia/tratamento farmacológico
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