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1.
Nucleic Acids Res ; 2024 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-39291738

RESUMO

The human telomere system is highly dynamic. Both short and long leucocyte average telomere lengths (aTL) are associated with an increased risk of cancer and early death, illustrating the complex relationship between TL and human health and the importance of assessing TL distributions with single TL analysis. A DNA microarray and telomere fluorescent in situ hybridization (DNA-array-FISH) approach was developed to measure the base-pair (bp) lengths of single telomeres. On average 32000 telomeres were measured per DNA sample with one microarray chip assaying 96 test DNA samples. Various telomere parameters, i.e. aTL and the frequency of short/long telomeres, were computed to delineate TL distribution. The intra-assay and inter-assay coefficient of variations of aTL ranged from 1.37% to 3.98%. The correlation coefficient (r) of aTL in repeated measurements ranged from 0.91 to 1.00, demonstrating high measurement precision. aTLs measured by DNA-array-FISH predicted aTLs measured by terminal restriction fragment (TRF) analysis with r ranging 0.87-0.99. A new accurate and high-throughput method has been developed to measure the bp lengths of single telomeres. The large number of single TL data provides an opportunity for an in-depth analysis of telomere dynamics and the complex relationship between telomere and age-related diseases.

2.
Nucleic Acids Res ; 46(19): e117, 2018 11 02.
Artigo em Inglês | MEDLINE | ID: mdl-30010842

RESUMO

Telomeres are the end-caps of chromosomes that serve to protect the integrity of the genome. Below certain critical lengths, the telomeres can no longer fulfill their protective function, and chromosomal instability ensues. Telomeres shorten during normal cell division due to the end replication problem and are implicated in the development of various aging-associated diseases, including cancer. Telomere length has the potential to serve as a useful biomarker in the field of aging and cancer. However, existing methods of telomere measurement are either too laborious, unable to provide absolute measurement of individual telomere lengths, or limited to certain chromosomes or cell types. Here, we describe an easy single-molecule, fluorescence spectroscopic method for measuring the length of telomeres that permits the profiling of absolute telomere lengths in any DNA sample. We have demonstrated the accurate detection of telomeres as short as 100 bp using cloned telomere standards, and have profiled telomere lengths in human cancer cell lines and primary cells. Since this method allows direct comparison between samples, it could greatly improve the clinical utility of telomere biomarkers.


Assuntos
Análise Mutacional de DNA/métodos , Técnicas Analíticas Microfluídicas/métodos , Imagem Individual de Molécula/métodos , Telômero/química , Envelhecimento/genética , Células Cultivadas , Instabilidade Cromossômica/genética , Humanos , Dispositivos Lab-On-A-Chip , Neoplasias/genética , Hibridização de Ácido Nucleico/métodos , Ácidos Nucleicos Peptídicos/química , Polimorfismo Genético , Reprodutibilidade dos Testes , Espectrometria de Fluorescência/métodos , Telômero/genética , Telômero/metabolismo , Homeostase do Telômero/genética , Encurtamento do Telômero/genética
3.
Int J Cancer ; 142(11): 2234-2243, 2018 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-29318605

RESUMO

Telomeres are crucial in the maintenance of chromosome integrity and genomic stability. Critically short telomeres can trigger programed cell death while cells with longer telomeres may have increased likelihood of replicative errors, resulting in genetic mutations and chromosomal alterations, and ultimately promoting oncogenesis. Data on telomere length and lung cancer risk from large prospective cohort studies are spare. Relative telomere length in peripheral blood leukocytes was quantified using a validated monochrome multiplex quantitative polymerase chain reaction (qPCR) method in 26,540 participants of the Singapore Chinese Health Study. After a follow-up of 12 years, 654 participants developed lung cancer including 288 adenocarcinoma, 113 squamous cell carcinoma and 253 other/unknown histological type. The Cox proportional hazard regression was used to estimate hazard ratio (HR) and 95% confidence interval (CI). HR of lung adenocarcinoma for individuals in the highest comparing the lowest 20 percentile of telomere length was 2.84 (95% CI 1.94-4.14, ptrend < 0.0001). This positive association was present in never smokers (ptrend < 0.0001), ever smokers (ptrend = 0.0010), men (ptrend = 0.0003), women (ptrend < 0.0001), and in shorter (ptrend = 0.0002) and longer (ptrend = 0.0001) duration of follow-up. There was no association between telomere length and risk of squamous cell carcinoma or other histological type of lung cancer in all or subgroups of individuals. The agreement of results from this prospective cohort study with those of previous prospective studies and Mendelian randomization studies suggest a possible etiological role of telomere length in the development of lung adenocarcinoma.


Assuntos
Adenocarcinoma/epidemiologia , Adenocarcinoma/genética , Leucócitos/metabolismo , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/genética , Homeostase do Telômero , Telômero/genética , Idoso , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Modelos de Riscos Proporcionais , Risco , Medição de Risco , Singapura/epidemiologia
4.
Breast Cancer Res Treat ; 168(2): 467-479, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29230660

RESUMO

PURPOSE: This project was undertaken to examine the association between dietary intake of soy or cruciferous vegetables and breast cancer treatment-related symptoms among Chinese-American (CA) and Non-Hispanic White (NHW) breast cancer survivors. METHODS: This cross-sectional study included 192 CA and 173 NHW female breast cancer survivors (stages 0-III, diagnosed between 2006 and 2012) recruited from two California cancer registries, who had completed primary treatment. Patient-reported data on treatment-related symptoms and potential covariates were collected via telephone interviews. Dietary data were ascertained by mailed questionnaires. The outcomes evaluated were menopausal symptoms (hot flashes, night sweats, vaginal dryness, vaginal discharge), joint problems, fatigue, hair thinning/loss, and memory problems. Associations between soy and cruciferous vegetables and symptoms were assessed using logistic regression. Analyses were further stratified by race/ethnicity and endocrine therapy usage (non-user, tamoxifen, aromatase inhibitors). RESULTS: Soy food and cruciferous vegetable intake ranged from no intake to 431 and 865 g/day, respectively, and was higher in CA survivors. Higher soy food intake was associated with lower odds of menopausal symptoms (≥ 24.0 vs. 0 g/day, OR 0.51, 95% CI 0.25, 1.03), and fatigue (≥ 24.0 vs. 0 g/day, OR 0.43, 95% CI 0.22, 0.84). However, when stratified by race/ethnicity, associations were statistically significant in NHW survivors only. Compared with low intake, higher cruciferous vegetable intake was associated with lower odds of experiencing menopausal symptoms (≥ 70.8 vs. < 33.0 g/day, OR 0.50, 95% CI 0.25, 0.97) in the overall population. CONCLUSIONS: In this population of breast cancer survivors, higher soy and cruciferous vegetable intake was associated with less treatment-related menopausal symptoms and fatigue.


Assuntos
Antineoplásicos Hormonais/efeitos adversos , Neoplasias da Mama/tratamento farmacológico , Sobreviventes de Câncer/estatística & dados numéricos , Inquéritos sobre Dietas/estatística & dados numéricos , Alimentos de Soja , Verduras , Idoso , Inibidores da Aromatase/efeitos adversos , Asiático/estatística & dados numéricos , Neoplasias da Mama/mortalidade , California/epidemiologia , Comparação Transcultural , Estudos Transversais , Fadiga/induzido quimicamente , Fadiga/dietoterapia , Feminino , Hispânico ou Latino/estatística & dados numéricos , Humanos , Menopausa/efeitos dos fármacos , Pessoa de Meia-Idade , População Branca/estatística & dados numéricos
5.
Breast Cancer Res Treat ; 168(2): 481-482, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29327296

RESUMO

In the original publication, the values provided for the isoflavone and glucosinolate intake variables were incorrectly labeled in Table 1. The correct values of 6.3 mg/day for isoflavone intake, and 20.4 mg/day and 50.1 mg/day for glucosinolate intake are provided in this erratum.

6.
Carcinogenesis ; 36(11): 1284-90, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26342126

RESUMO

Although it is widely recognized that telomere dysfunction plays an important role in cancer, the relationship between telomere function and bladder cancer risk is not well defined. In a case-control study of bladder cancer in Egypt, we examined relationships between two telomere features and bladder cancer risk. Telomere fluorescent in situ hybridization was used to measure telomere features using short-term cultured blood lymphocytes. Logistic regression was used to estimate the strength of association between telomere features and the risk of urothelial carcinoma of the bladder. High telomere length variation (TLV) across all chromosomal ends was significantly associated with an increased risk of bladder cancer [adjusted odds ratios (OR) = 2.22, 95% confidence interval (CI) = 1.48-3.35], as was long average telomere length (OR = 3.19, 95% CI = 2.07, 4.91). Further, TLV and average telomere length jointly affected bladder cancer risk: when comparing individuals with long telomere length and high TLV to those with short telomere length and low TLV, the adjusted OR was 14.68 (95% CI: 6.74-31.98). These associations were stronger among individuals who are 60 years of age or younger. In summary, long and heterogeneous telomere length in blood lymphocytes was strongly associated with an increased bladder cancer risk in Egyptian and the association was modulated by age.


Assuntos
Linfócitos/fisiologia , Homeostase do Telômero , Telômero/genética , Neoplasias da Bexiga Urinária/genética , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/genética , Estudos de Casos e Controles , Egito , Feminino , Estudos de Associação Genética , Predisposição Genética para Doença , Humanos , Masculino , Pessoa de Meia-Idade , Fatores de Risco
7.
J Natl Cancer Inst ; 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39196709

RESUMO

The central premise of this article is that a portion of the established relationships between social determinants of health and racial/ethnic disparities in cancer morbidity and mortality are mediated through differences in rates of biological aging processes. We further posit that using knowledge about aging could enable discovery and testing of new mechanism-based pharmaceutical and behavioral interventions ("gerotherapeutics") to differentially improve the health of minoritized cancer survivors and reduce cancer disparities. These hypotheses are based on evidence that lifelong differences in adverse social determinants of health contribute to disparities in rates of biological aging ("social determinants of aging"), with minoritized groups having accelerated aging (ie, a steeper slope or trajectory of biological aging over time relative to chronological age) more often than non-minoritized groups. Acceleration of biological aging can increase the risk, age of onset, aggressivity and/or stage of many adult cancers. There are also documented negative feedback loops whereby the cellular damage caused by cancer and its therapies act as drivers of additional biological aging. Together, these dynamic intersectional forces can contribute to differences in cancer outcomes between minoritized vs non-minoritized survivor populations. We highlight key targetable biological aging mechanisms with potential applications to reducing cancer disparities and discuss methodological considerations for pre-clinical and clinical testing of the impact of gerotherapeutics on cancer outcomes in minoritized populations. Ultimately, the promise of reducing cancer disparities will require broad societal policy changes that address the structural causes of accelerated biological aging and ensure equitable access to all new cancer control paradigms.

8.
Hum Mol Genet ; 20(2): 378-86, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20956286

RESUMO

Although telomere dysfunction is a characteristic of breast cancer cells, the relationship between deficiency on individual chromosomal telomeres in normal somatic cells and breast cancer risk has not been characterized. A case-control study was conducted to examine the associations between individual lengths of 92 telomeres in the human genome and the risk of breast cancer in 204 newly diagnosed breast cancer patients and 236 healthy controls. Chromosome arm-specific telomere lengths were measured by telomere quantitative fluorescent in situ hybridization. Unconditional logistic regression was used to estimate the risk associations. This genome-wide screen identified that shorter telomere lengths on chromosomes Xp and 15p were associated with breast cancer risk in pre-menopausal women, with adjusted odds ratios (aORs) of 2.5 (95% CI = 1.3, 4.8) and 2.6 (1.3, 5.0), respectively. The study also revealed that greater length differences between homologous telomeres on chromosomes 9p, 15p and 15q were associated with breast cancer risk in pre-menopausal women, with aORs of 4.6 (2.3, 9.2), 3.1 (1.6, 6.0) and 2.8 (1.4, 5.4), respectively. When the subjects were categorized into quartiles, a dose-response relationship was observed for all of the above telomeres (P-for-trend ≤ 0.005). This study revealed that telomere deficiencies on chromosomes 9p, 15p, 15q and Xp were associated with breast cancer risk in pre-menopausal women. If confirmed in future studies, chromosomal arm-specific telomeres are likely to be a useful panel of blood-based biomarkers for breast cancer risk assessment, given their strong associations with breast cancer risk.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 15 , Cromossomos Humanos Par 9 , Cromossomos Humanos X , Marcadores Genéticos , Telômero/genética , Adulto , Estudos de Casos e Controles , Instabilidade Cromossômica , Feminino , Predisposição Genética para Doença , Humanos , Pessoa de Meia-Idade , Fatores de Risco
9.
Cancers (Basel) ; 15(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36831502

RESUMO

(1) Background: Colorectal cancer risk and survival have previously been associated with telomere length in peripheral blood leukocytes and tumor tissue. A systematic review and meta-analysis of the literature was conducted. The PubMed, Embase, and Web of Science databases were searched through March 2022. (2) Methods: Relevant studies were identified through database searching following PRISMA guidelines. Risk estimates were extracted from identified studies; meta-analyses were conducted using random effects models. (3) Results: Fourteen studies were identified (eight on risk; six on survival) through systematic review. While no association was observed between circulating leukocyte telomere length and the risk of colorectal cancer [overall OR (95% CI) = 1.01 (0.82-1.24)], a worse survival for those with shorter telomeres in leukocytes and longer telomeres in tumor tissues was observed [Quartile1/Quartile2-4 overall HR (95% CI) = 1.41 (0.26-7.59) and 0.82 (0.69-0.98), respectively]. (4) Conclusions: Although there was no association with colorectal cancer risk, a poorer survival was observed among those with shorter leukocyte telomere length. Future larger studies evaluating a potentially non-linear relationship between telomeres and colorectal cancer are needed.

10.
Carcinogenesis ; 33(1): 113-8, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22072619

RESUMO

A better understanding of the risk of local recurrence (LR) will facilitate therapeutic decision making in the management of early breast cancers. In the present study, we investigated whether telomere length in the normal breast epithelial cells surrounding the tumor is predictive of breast cancer LR; 152 women who were diagnosed with breast cancer at the Lombardi Comprehensive Cancer Center were included in this nested case-control study. Cases (patients had LR) and controls (patients had no LR) were matched on year of surgery, age at diagnosis and type of surgery. Telomere fluorescent in situ hybridization was used to determine the telomere length using formalin fixed paraffin-embedded breast tissues. Small telomere length variation (TLV), defined as the coefficient variation of telomere lengths among examined cells, in normal epithelial cells adjacent to the tumor was significantly associated with a 5-fold (95% confidence interval = 1.2-22.2) increased risk of breast cancer LR. When the subjects were categorized into quartiles, a significant inverse dose-response relationship was observed with lowest versus highest quartile odds ratio of 15.3 (P(trend) = 0.012). Patients who had large TLV had significantly better 10 year recurrence free survival rate compared with patients who had small TLV (80 versus 33%). The present study revealed that TLV in normal epithelial cells adjacent to tumor is a strong predictor of breast cancer LR. If confirmed by future studies, TLV in normal epithelial cells adjacent to tumor has the potential to become a promising biomarker for predicting breast cancer LR after breast conserving surgery.


Assuntos
Neoplasias da Mama/genética , Células Epiteliais/ultraestrutura , Recidiva Local de Neoplasia/genética , Telômero , Adulto , Idoso , Biomarcadores Tumorais , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Humanos , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/patologia , Células Estromais/ultraestrutura
11.
Carcinogenesis ; 31(4): 654-9, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-20110285

RESUMO

UNLABELLED: Given the high incidence of breast cancer and that more than half of cases remain unexplained, the need to identify risk factors for breast cancer remains. Deficiencies in DNA repair capacity have been associated with cancer risk. The mutagen sensitivity assay (MSA), a phenotypic marker of DNA damage response and repair capacity, has been consistently shown to associate with the risk of tobacco-related cancers. METHODS: In a case-control study of 164 women with breast cancer and 165 women without the disease, we investigated the association between mutagen sensitivity and risk of breast cancer using bleomycin as the mutagen. RESULTS: High bleomycin sensitivity (>0.65 breaks per cell) was associated with an increased risk of breast cancer, with an adjusted odds ratio of 2.8 [95% confidence interval (CI) = 1.7-4.5]. Risk increased with greater number of bleomycin-induced chromosomal breaks (P(trend) = 0.01). The association between bleomycin sensitivity and breast cancer risk was greater for women who were black, premenopausal and ever smokers. Our data also suggest that bleomycin sensitivity may modulate the effect of tobacco smoking on breast cancer risk. Among women with hypersensitivity to bleomycin, ever smokers had a 1.6-fold increased risk of breast cancer (95% CI = 0.6-3.9, P for interaction between tobacco smoking and bleomycin sensitivity = 0.32). CONCLUSIONS: Increased bleomycin sensitivity is significantly associated with an increased risk of breast cancer in both pre- and postmenopausal women. Our observation that the effect of tobacco smoking on breast cancer risk may differ based on mutagen sensitivity status warrants further investigation.


Assuntos
Bleomicina/toxicidade , Neoplasias da Mama/etiologia , Mutagênicos/toxicidade , Fumar/efeitos adversos , Adulto , Idoso , Estudos de Casos e Controles , Reparo do DNA , Terapia de Reposição de Estrogênios/efeitos adversos , Feminino , Humanos , Modelos Logísticos , Menopausa , Pessoa de Meia-Idade , Razão de Chances , Risco
12.
Carcinogenesis ; 31(10): 1778-86, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20729390

RESUMO

The role of tumor estrogen receptors (ERs) and serum estrogen in lung cancer is inconclusive. We investigated the hypothesis that ERs and functional single-nucleotide polymorphisms in the estrogen biosynthesis pathway are associated with poorer lung cancer survival. Lung cancer patients (n = 305) from a National Cancer Institute-Maryland (NCI-MD) case-case cohort in the Baltimore metropolitan area were used as a test cohort. To validate, 227 cases from the NCI-MD case-control cohort and 293 cases from a Norwegian lung cancer cohort were studied. Information on demographics, tobacco and reproductive histories was collected in an interviewer-administered questionnaire. Serum estrogen, progesterone, tumor messenger RNA expression of hormone receptors and germ line DNA polymorphisms were analyzed for associations with lung cancer survival. Patients in the highest tertile of serum estrogen had worse survival in all three cohorts (P combined < 0.001). Furthermore, the variant allele of estrogen receptor alpha (ER-α) polymorphism (rs2228480) was significantly associated with increased tumor ER-α levels and worse survival in all three cohorts [hazard ratio (HR) = 2.59, 95% confidence interval (CI): 1.20- 4.01; HR = 1.76, 95% CI: 1.08-2.87 and HR = 2.85, 95% CI: 1.31-4.36). Other polymorphisms associated with lower serum estrogen correlated with improved survival. Results were independent of gender and hormone replacement therapy. We report a significant association of increased serum estrogen with poorer survival among lung cancer male and female patients. Understanding the genetic control of estrogen biosynthesis and response in lung cancer could lead to improved prognosis and therapy.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/mortalidade , Receptor alfa de Estrogênio/análise , Estrogênios/sangue , Neoplasias Pulmonares/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/genética , Estudos de Casos e Controles , Estudos de Coortes , Citocromo P-450 CYP1A1/genética , Receptor alfa de Estrogênio/genética , Feminino , Humanos , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/genética , Masculino , Pessoa de Meia-Idade , Polimorfismo de Nucleotídeo Único , Progesterona/sangue , Prognóstico , RNA Mensageiro/análise
13.
Int J Cancer ; 126(9): 2199-210, 2010 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-19626602

RESUMO

Cell cycle checkpoints play critical roles in the maintenance of genomic integrity and inactivation of checkpoint genes are frequently perturbed in most cancers. In a case-control study of 299 non-small cell lung cancer cases and 550 controls in Baltimore, we investigated the association between gamma-radiation-induced G(2)/M arrest in cultured blood lymphocytes and lung cancer risk, and examined genotype-phenotype correlations between genetic polymorphisms of 20 genes involving in DNA repair and cell cycle control and gamma-radiation-induced G(2)/M arrest. The study was specifically designed to examine race and gender differences in risk factors. Our data indicated that a less efficient DNA damage-induced G(2)/M checkpoint was associated with an increased risk of lung cancer in African American women with an adjusted odds ratio (OR) of 2.63 (95% CI = 1.01-7.26); there were no statistically significant associations for Caucasians, or African American men. When the African American women were categorized into quartiles, a significant reverse trend of decreased G(2)/M checkpoint function and increased lung cancer risk was present, with lowest-vs.-highest quartile OR of 13.72 (95% CI = 2.30-81.92, p(trend) < 0.01). Genotype-phenotype correlation analysis indicated that polymorphisms in ATM, CDC25C, CDKN1A, BRCA2, ERCC6, TP53, and TP53BP1 genes were significantly associated with the gamma-radiation-induced G(2)/M arrest phenotype. This study provides evidence that a less efficient G(2)/M checkpoint is significantly associated with lung cancer risk in African American women. The data also suggested that the function of G(2)/M checkpoint is modulated by genetic polymorphisms in genes involved in DNA repair and cell cycle control.


Assuntos
Divisão Celular , Fase G2 , Genes cdc/fisiologia , Neoplasias Pulmonares/etiologia , Idoso , Estudos de Casos e Controles , Reparo do DNA , Feminino , Genótipo , Humanos , Neoplasias Pulmonares/patologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Polimorfismo de Nucleotídeo Único , Fatores de Risco
14.
Breast Cancer Res Treat ; 120(3): 769-75, 2010 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19543829

RESUMO

Telomere dysfunction, which leads to genomic instability, is hypothesized to play a causal role in the development of breast cancer. However, the few epidemiologic studies that assessed the relationship between telomere length in blood cells and breast cancer risk have been inconsistent. We conducted two case-control studies to further understand the role of telomere length and breast cancer risk. Overall telomere lengths were measured by telomere quantitative fluorescent in situ hybridization (TQ-FISH) and telomere quantitative real-time PCR (TQ-PCR). The associations between telomere length in blood leukocytes and risk of breast cancer were examined in two breast cancer case-control studies that were conducted at Roswell Park Cancer Institute (RPCI) and Lombardi Comprehensive Cancer Center (LCCC). Using the 50th percentile value in controls as a cut point, women who had shorter telomere length were not at significantly increased risk of breast cancer compared with women who had longer telomere length in the RPCI study (odds ratio [OR] = 1.34, 95% confidence interval [CI] = 0.84-2.12), in the LCCC study (OR = 1.18, 95% CI = 0.73-1.91), or in the combined RPCI and LCCC studies (OR = 1.23, 95% CI = 0.89-1.71). There was no significant dose-response relationship across quartiles of telomere length and no significant difference when comparing women in the lowest to highest quartile of telomere length. Overall telomere length in blood leukocytes was not significantly associated with the risk of breast cancer.


Assuntos
Neoplasias da Mama/epidemiologia , Leucócitos/ultraestrutura , Telômero/ultraestrutura , Adulto , Idoso , Neoplasias da Mama/sangue , Neoplasias da Mama/genética , Estudos de Casos e Controles , Feminino , Humanos , Hibridização in Situ Fluorescente , Menopausa , Pessoa de Meia-Idade , Reação em Cadeia da Polimerase , Grupos Raciais , Fatores de Risco , Fumar/epidemiologia , Fatores Socioeconômicos
15.
Carcinogenesis ; 30(8): 1380-6, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19535548

RESUMO

BACKGROUND: Telomere dysfunction is involved in the development of breast cancer and very short telomeres are frequent genetic alterations in breast tumors. However, the influence of telomere lengths of specific chromosomal arms on the breast cancer risk is unknown. METHODS: We conducted a case-control study of breast cancer to examine the associations of the telomere length on chromosome 9 short arms (9p) and long arms (9q) with risk of breast cancer. Chromosome 9 arm-specific telomere lengths were measured by quantitative fluorescent in situ hybridization using cultured blood lymphocytes. RESULTS: Telomere length on chromosome 9p was significantly shorter in breast cancer patients than in control subjects (P < 0.001). Using the 50th percentile value in controls as a cut point, women who have short 9p telomeres had an increased risk of breast cancer [adjusted odds ratio (OR) = 2.6; 95% confidence interval (CI) = 1.5-4.3]. When the 9p telomere length was divided into quartiles, a significant inverse dose-response relationship between 9p telomere length and breast cancer risk was observed (P(trend) < 0.001), with a quartile ORs of 3.0 (95% CI = 1.2-7.5), 3.9 (95% CI = 1.6-9.5) and 6.6 (95% CI = 2.8-15.9) for third, second and first quartile, respectively, when compared with women in the fourth quartile. CONCLUSIONS: Short telomere length on chromosome 9p is strongly associated with the risk of breast cancer. If confirmed by future studies, chromosome 9p telomere length has the potential to be incorporated into the current prediction models to significantly enhance breast cancer risk prediction.


Assuntos
Neoplasias da Mama/genética , Cromossomos Humanos Par 9/genética , Telômero/genética , Neoplasias da Mama/sangue , Neoplasias da Mama/patologia , Estudos de Casos e Controles , Feminino , Humanos , Hibridização in Situ Fluorescente , Linfócitos , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Razão de Chances , Prognóstico , Fatores de Risco
16.
Cancer Epidemiol Biomarkers Prev ; 18(1): 215-22, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19124500

RESUMO

Accumulating evidence suggests a role for inflammation in the development and progression of cancer. Our group recently identified a cytokine gene signature in lung tissue associated with lung cancer prognosis. Therefore, we hypothesized that concentrations of circulating cytokines in serum may be associated with lung cancer survival. Ten serum cytokines, namely, interleukin (IL)-1beta, IL-4, IL-5, IL-6, IL-8, IL-10, IL-12, granulocyte macrophage colony-stimulating factor, interferon (IFN)-gamma, and tumor necrosis factor-alpha, were assessed in 353 non-small cell lung cancer cases from a case-control study of lung cancer in the greater Baltimore, Maryland area. Cytokines were measured using an ultrasensitive electrochemiluminescence immunoassay. IL-6 serum concentrations (>or=4.0 pg/mL) were associated with significantly poorer survival in both African Americans [hazard ratio (HR), 2.71; 95% confidence interval (CI), 1.26-5.80] and Caucasians (HR, 1.71; 95% CI, 1.22-2.40). IL-10 (HR, 2.62; 95% CI, 1.33-5.15) and IL-12 (HR, 1.98; 95% CI, 1.14-3.44) were associated with lung cancer survival only in African Americans. Some evidence for an association of tumor necrosis factor-alpha levels with survival in Caucasians was observed, although these results were not significant. These hypothesis-generating findings indicate that selected serum cytokine concentrations are associated with lung cancer survival, and indicate that further research is warranted to better understand the mechanistic underpinnings of these associations.


Assuntos
Negro ou Afro-Americano , Carcinoma Pulmonar de Células não Pequenas/sangue , Carcinoma Pulmonar de Células não Pequenas/mortalidade , Citocinas/sangue , Neoplasias Pulmonares/sangue , Neoplasias Pulmonares/mortalidade , População Branca , Idoso , Carcinoma Pulmonar de Células não Pequenas/etnologia , Estudos de Casos e Controles , Feminino , Humanos , Neoplasias Pulmonares/etnologia , Masculino , Maryland/epidemiologia , Estudos Prospectivos , Análise de Sobrevida
17.
Int J Biol Macromol ; 122: 1244-1252, 2019 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-30227201

RESUMO

α-Glucosidase is a critical enzyme associated with diabetes mellitus, and the inhibitors of the enzyme play important roles in the treatment of the disease. In this study, the inhibitory effect and mechanism of rifampicin on α-glucosidase were investigated by multispectroscopic methods along with molecular docking technique. The results showed that rifampicin inhibited α-glucosidase activity prominently (IC50 = 135 ±â€¯1.2 µM) in a reversible and competitive-type manner. The fluorescence intensity of α-glucosidase was quenched by rifampicin through forming rifampicin-α-glucosidase complex in a static procedure. And the formation of the rifampicin-α-glucosidase complex was driven spontaneously by hydrophobic forces and hydrogen bonds. The results obtained from molecular docking further indicated that hydrophobic forces were formed between rifampicin and amino acid residues Phe 173, Pro151, and hydrogen bonds were generated by the interactions of rifampicin with residues Ser 180, Asn 414, Gly160, and Gly161 of α-glucosidase. Moreover, it was found that the binding of rifampicin to α-glucosidase could alter the conformation of the enzyme to make it steady, and the binding distance was estimated to be 1.02 nm. Therefore, this study confirmed a novel α-glucosidase inhibitor and possibly contributed to the improvement of newfangled anti-diabetic agent.


Assuntos
Inibidores de Glicosídeo Hidrolases/metabolismo , Inibidores de Glicosídeo Hidrolases/farmacologia , Simulação de Acoplamento Molecular , Rifampina/metabolismo , Rifampina/farmacologia , alfa-Glucosidases/metabolismo , Sítios de Ligação , Transferência de Energia , Cinética , Conformação Proteica , Análise Espectral , Termodinâmica , alfa-Glucosidases/química
18.
Food Funct ; 10(1): 99-111, 2019 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-30565612

RESUMO

Condensed tannins contained in food are known to have many beneficial impacts on human health. In this study, we attempt to evaluate the structural features, antityrosinase effects, anti-melanogenesis properties, antioxidant activity and DNA damage protection activity of condensed tannins purified from the seeds of Vigna angularis (Willd.) Ohwi et Ohashi. MALDI-TOF MS, ESI-Full-MS, and HPLC-ESI-MS demonstrated that condensed tannins are composed of procyanidins, prodelphinidins and their gallates, among which procyanidins are the dominant components. As reversible and mixed-type inhibitors of tyrosinase, condensed tannins from V. angularis strongly inhibited the monophenolase and odiphenolase activities with IC50 values of 130.0 ± 0.5 and 35.1 ± 2.0 µg mL-1, respectively. What's more, condensed tannins had a good inhibitory effect on cell proliferation, cellular tyrosinase activity, and melanogenesis of B16 mouse melanoma cells. Based on fluorescence quenching analyses, these compounds were determined to be effective quenchers of the enzyme and its substrates. According to molecular docking, the strong interaction between condensed tannins and tyrosinase was mainly driven by hydrogen bonding and hydrophobic force. In addition, condensed tannins showed a powerful antioxidant capacity and DNA damage protection activity. Therefore, condensed tannins from V. angularis have feasible applications in food, medicine, and the cosmetics industry.


Assuntos
Antioxidantes/farmacologia , Dano ao DNA/efeitos dos fármacos , Melaninas/metabolismo , Extratos Vegetais/farmacologia , Proantocianidinas/farmacologia , Substâncias Protetoras/farmacologia , Vigna/química , Animais , Antioxidantes/química , Linhagem Celular , Humanos , Melanoma , Camundongos , Estrutura Molecular , Monofenol Mono-Oxigenase/antagonistas & inibidores , Monofenol Mono-Oxigenase/metabolismo , Extratos Vegetais/química , Proantocianidinas/química , Substâncias Protetoras/química , Sementes/química , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
19.
Cells ; 8(11)2019 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-31717887

RESUMO

Traditional cancer models including cell lines and animal models have limited applications in both basic and clinical cancer research. Genomics-based precision oncology only help 2-20% patients with solid cancer. Functional diagnostics and patient-derived cancer models are needed for precision cancer biology. In this review, we will summarize applications of conditional cell reprogramming (CR) in cancer research and next generation living biobanks (NGLB). Together with organoids, CR has been cited in two NCI (National Cancer Institute, USA) programs (PDMR: patient-derived cancer model repository; HCMI: human cancer model initiatives. HCMI will be distributed through ATCC). Briefly, the CR method is a simple co-culture technology with a Rho kinase inhibitor, Y-27632, in combination with fibroblast feeder cells, which allows us to rapidly expand both normal and malignant epithelial cells from diverse anatomic sites and mammalian species and does not require transfection with exogenous viral or cellular genes. Establishment of CR cells from both normal and tumor tissue is highly efficient. The robust nature of the technique is exemplified by the ability to produce 2 × 106 cells in five days from a core biopsy of tumor tissue. Normal CR cell cultures retain a normal karyotype and differentiation potential and CR cells derived from tumors retain their tumorigenic phenotype. CR also allows us to enrich cancer cells from urine (for bladder cancer), blood (for prostate cancer), and pleural effusion (for non-small cell lung carcinoma). The ability to produce inexhaustible cell populations using CR technology from small biopsies and cryopreserved specimens has the potential to transform biobanking repositories (NGLB: next-generation living biobank) and current pathology practice by enabling genetic, biochemical, metabolomic, proteomic, and biological assays, including chemosensitivity testing as a functional diagnostics tool for precision cancer medicine. We discussed analyses of patient-derived matched normal and tumor models using a case with tongue squamous cell carcinoma as an example. Last, we summarized applications in cancer research, disease modeling, drug discovery, and regenerative medicine of CR-based NGLB.


Assuntos
Técnicas de Reprogramação Celular/métodos , Reprogramação Celular/fisiologia , Amidas , Animais , Bancos de Espécimes Biológicos/tendências , Biópsia , Carcinoma Pulmonar de Células não Pequenas/patologia , Carcinoma de Células Escamosas/patologia , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Linhagem Celular , Linhagem Celular Tumoral , Técnicas de Cocultura/métodos , Células Epiteliais/patologia , Humanos , Neoplasias Pulmonares/patologia , Masculino , Modelos Biológicos , Medicina de Precisão/métodos , Neoplasias da Próstata/patologia , Proteômica , Piridinas , Neoplasias da Bexiga Urinária/patologia
20.
Mol Cell Biol ; 25(3): 1070-80, 2005 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-15657433

RESUMO

Mammalian telomeric DNA contains duplex TTAGGG repeats and single-stranded overhangs. POT1 (protection of telomeres 1) is a telomere-specific single-stranded DNA-binding protein, highly conserved in eukaryotes. The biological function of human POT1 is not well understood. In the present study, we demonstrate that POT1 plays a key role in telomeric end protection. The reduction of POT1 by RNA interference led to the loss of telomeric single-stranded overhangs and induced apoptosis, chromosomal instability, and senescence in cells. POT1 and TRF2 interacted with each other to form a complex with telomeric DNA. A dominant negative TRF2, TRF2(DeltaBDeltaM), bound to POT1 and prevented it from binding to telomeres. POT1 overexpression protected against TRF2(DeltaBDeltaM)-induced loss of telomeric single-stranded overhangs, chromosomal instability, and senescence. These results demonstrate that POT1 and TRF2 share in part in the same pathway for telomere capping and suggest that POT1 binds to the telomeric single-stranded DNA in the D-loop and cooperates with TRF2 in t-loop maintenance.


Assuntos
Apoptose/fisiologia , Senescência Celular/fisiologia , Proteínas de Ligação a Telômeros/metabolismo , Telômero/metabolismo , Proteína 2 de Ligação a Repetições Teloméricas/metabolismo , Instabilidade Cromossômica/fisiologia , Fibroblastos/metabolismo , Humanos , Hibridização in Situ Fluorescente , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Complexo Shelterina , Células Tumorais Cultivadas
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