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1.
Eur Rev Med Pharmacol Sci ; 23(17): 7639-7648, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31539156

RESUMO

OBJECTIVE: Recent studies highlighted long noncoding RNAs (lncRNAs) have been implicated in many biological processes and diseases. However, atherosclerosis is a major risk factor for cardiovascular disease, but the detailed mechanism of atherosclerosis progression remained unclear. In this study, we mainly focused on the role of lncRNA Chaer in atherosclerosis. PATIENTS AND METHODS: RT-PCR was used to detect the expression of lncRNA Chaer in atherosclerosis patients and animal model. Moreover, the expression of Chaer in vascular smooth muscle cell dysfunction model was also measured. Proliferation ability was tested by CCK-8 and cyclin D1 assay, through loss- and gain-of-function approaches. Western-blot was used to measure the expression of H3 lysine 27 methylation, when Chaer was in different levels. RIP and ChIP assay discovered an interaction between Chaer and PRC2 through mTOR signaling. RESULTS: Here we identified a heart-enriched long non-coding RNA, named Cardiac Hypertrophy Associated Epigenetic Regulator (Chaer). We found that the Chaer was highly expressed in serum samples from 28 patients with atherosclerosis, compared with 28 healthy volunteers. Chaer was dramatically upregulated in atherosclerotic plaques of ApoE-/- mice. We also found that the expression of Chaer was upregulated in vascular smooth muscle cell injury model. Through loss- and gain-of-function approaches, we showed that Chaer promotes cell proliferation and induces apoptosis in vitro. Mechanistically, Chaer interacts with Polycomb Repressor Complex 2 (PRC2) through inhibiting histone H3 lysine 27 methylation. Further, this interaction is induced upon mTOR signaling pathway. CONCLUSIONS: According to the results, we found that lncRNA Chaer was closely related to the progression of atherosclerosis, which could be a previously uncharacterized lncRNA-dependent epigenetic checkpoint.


Assuntos
Aterosclerose/patologia , Complexo Repressor Polycomb 2/metabolismo , RNA Longo não Codificante/metabolismo , Serina-Treonina Quinases TOR/metabolismo , Adulto , Idoso , Animais , Apoptose/efeitos dos fármacos , Aterosclerose/genética , Aterosclerose/metabolismo , Linhagem Celular , Feminino , Humanos , Masculino , Camundongos , Camundongos Knockout , Pessoa de Meia-Idade , Complexo Repressor Polycomb 2/genética , Interferência de RNA , RNA Longo não Codificante/antagonistas & inibidores , RNA Longo não Codificante/genética , RNA Interferente Pequeno/metabolismo , Transdução de Sinais , Fator de Necrose Tumoral alfa/farmacologia , Regulação para Cima/efeitos dos fármacos
2.
Eur Rev Med Pharmacol Sci ; 22(21): 7439-7447, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30468492

RESUMO

OBJECTIVE: Atherosclerosis is a major risk factor for cardiovascular disease, but its mechanism of progression remained unclear. However, many long non-coding RNAs (lncRNAs) have recently been implicated in different processes for cardiovascular disease. In this study, we mainly focused on the role of lncRNA TUG1 in atherosclerosis. PATIENTS AND METHODS: qRT-PCR was used to detect the expression of lncRNA TUG1 in atherosclerosis patients and animal model. Moreover, the expression of TUG1 in vascular smooth muscle cell dysfunction model was also measured. Proliferation ability was tested by CCK-8 and cyclin D1 assay, through loss- and gain-of function approaches. Western-blot was used to measure the expression of PTEN, when TUG1 was in different levels. RESULTS: We found that the lncRNA TUG1 was highly expressed in serum samples from 38 patients with atherosclerosis, compared with 24 healthy volunteers.  LncRNA TUG1 was dramatically upregulated in atherosclerotic plaques of ApoE-/- mice. We also found that the expression of TUG1 was upregulated in vascular smooth muscle cell injury model. Through loss- and gain-of function approaches, we showed that TUG1 promotes cell proliferation and induces apoptosis in vitro. What's more, TUG1 expression level was reversely correlated with PTEN expression in patients with atherosclerosis. LncRNA TUG1 could compete with PTEN for miR-21 binding. CONCLUSIONS: We found that lncRNA TUG1 was closely related to the progression of atherosclerosis, which could be a potential target for treating atherosclerosis.


Assuntos
Aterosclerose/etiologia , MicroRNAs/fisiologia , Músculo Liso Vascular/citologia , Miócitos de Músculo Liso/fisiologia , PTEN Fosfo-Hidrolase/fisiologia , RNA Longo não Codificante/fisiologia , Animais , Proliferação de Células , Células Cultivadas , Feminino , Humanos , Camundongos
3.
Anim Reprod Sci ; 195: 58-64, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29776696

RESUMO

The reproductive capacity of captive giant pandas is poor and sperm cryopreservation is necessary for the reproduction and conservation of this species. Cryopreservation, however, leads to a significant decrease in sperm quality, including sperm motility, acrosome integrity and DNA integrity. In the present study, a method was developed based on colloid single layer centrifugation that could significantly improve frozen-thawed sperm quality. Two colloids were compared for post-thaw giant panda sperm preparation; the sperm samples had greater total motility (Colloid 1: 44.5 ±â€¯16.0%, Colloid 2: 42.4 ±â€¯10.1% compared with Control: 25.4 ±â€¯8.4%, P < 0.05), linear velocity (Colloid 1: 17.2 ±â€¯8.3 µm/s; Colloid 2: 19.0 ±â€¯9.0 µm/s compared with Control: 6.6 ±â€¯1.7 µm/s, P < 0.05) and membrane integrity (Colloid: 46.9 ±â€¯13.2%; Colloid 2: 54.3 ±â€¯5.7% compared with Control: 36.0 ±â€¯9.1%; P < 0.05). This method could be a useful tool to enable the use of poor quality sperm samples and benefit this population by using available genetic material.


Assuntos
Centrifugação/veterinária , Criopreservação/veterinária , Análise do Sêmen/veterinária , Preservação do Sêmen/veterinária , Ursidae/fisiologia , Animais , Centrifugação/métodos , Criopreservação/métodos , Congelamento , Masculino , Preservação do Sêmen/métodos , Motilidade dos Espermatozoides , Espermatozoides
4.
Clin Radiol ; 73(8): 756.e17-756.e26, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29731125

RESUMO

AIM: To investigate the utility of intravoxel incoherent motion diffusion-weighted imaging (IVIM-DWI) in predicting the early response to concurrent chemoradiotherapy (CRT) in oesophageal squamous cell carcinoma (OSCC). MATERIALS AND METHODS: Thirty-three patients with OSCC who received CRT underwent IVIM-DWI at three time points (before CRT, at the end of radiotherapy 20 Gy, and immediately after CRT). After CRT, the patients were divided into the responders (complete response or partial response) and the non-responders (stable disease) based on RECIST 1.1. The IVIM-DWI parameters (apparent diffusion coefficient [ADC], true diffusion coefficient [D], the pseudo-diffusion coefficient [D*], and the perfusion fraction [f]) values and their percentage changes (Δvalue) at different time points were compared between the responders and the non-responders. Receiver-operating characteristic (ROC) curve analysis was used to determine the efficacy of IVIM-DWI parameters in identifying the response to CRT. RESULTS: The tumour regression ratio showed negative correlations with ADCpre (r=-0.610, p=0.000), ADC20 Gy (r=-0.518, p=0.002), Dpre (r=-0.584, p=0.000), and D20 Gy (r=-0.454, p=0.008), and positive correlation with ΔD20 Gy (r=0.361, p=0.039) and ΔDpost (r=0.626, p=0.000). Compared to the non-responders, the responders exhibited lower ADCpre, Dpre, ADC20 Gy, and D20 Gy, as well as higher ΔADC20 Gy, ΔD20 Gy, and ΔDpost (all p<0.05). Dpre had the highest sensitivity (92.9%) and value of area under the ROC curve (0.865) in differentiating the responders from the non-responders. CONCLUSION: Diffusion-related IVIM-DWI parameters (ADC and D) are potentially helpful in predicting the early treatment effect of CRT in OSCC.


Assuntos
Quimiorradioterapia , Imagem de Difusão por Ressonância Magnética/métodos , Carcinoma de Células Escamosas do Esôfago/diagnóstico por imagem , Carcinoma de Células Escamosas do Esôfago/terapia , Meios de Contraste , Feminino , Gadolínio DTPA , Humanos , Interpretação de Imagem Assistida por Computador , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Resultado do Tratamento
5.
J Viral Hepat ; 25(9): 1017-1025, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-29624802

RESUMO

The kinetics of serum hepatitis B surface antigen (HBsAg) during the natural history of hepatitis B virus (HBV) infection has been studied, but the factors affecting them remain unclear. We aimed to investigate the factors affecting HBsAg titres, using data from multicentre, large-sized clinical trials in China. The baseline data of 1795 patients in 3 multicentre trials were studied, and the patients were classified into 3 groups: hepatitis B early antigen (HBeAg)-positive chronic HBV infection (n = 588), HBeAg-positive chronic hepatitis B (n = 596), and HBeAg-negative chronic hepatitis B (n = 611). HBsAg titres in the different phases were compared, and multiple linear progression analyses were performed to investigate the implicated factors. HBsAg titres varied significantly in different phases (P = .000), with the highest (4.60 log10 IU/mL [10%-90% confidence interval: 3.52 log10 IU/mL-4.99 log10 IU/mL]) in patients with HBeAg-positive chronic HBV infection. In all phases, age and HBV DNA were correlated with serum HBsAg level. In HBeAg-positive chronic hepatitis B patients, a negative correlation between HBsAg titres and fibrosis stage was observed. Alanine amonitransferase or necroinflammatory activity was also correlated with HBsAg titres in HBeAg-negative chronic hepatitis B patients. In conclusion, decreased HBsAg titres may be associated with advancing fibrosis in HBeAg-positive chronic hepatitis B patients or increased necroinflammation in those with HBeAg-negative chronic hepatitis B. Our findings may help clinicians better understand the kinetics of HBsAg and provide useful insights into the management of this disease.


Assuntos
Antígenos de Superfície da Hepatite B/sangue , Hepatite B Crônica/complicações , Hepatite B Crônica/patologia , Cirrose Hepática/patologia , Soro/química , Adulto , Alanina Transaminase/sangue , China , DNA Viral/sangue , Feminino , Antígenos E da Hepatite B/sangue , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
6.
J Dairy Sci ; 100(9): 7035-7040, 2017 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-28668530

RESUMO

Isolation of mitochondrial DNA (mtDNA) from milk offers an effective way to monitor aspects of quality control and traceability to ensure food safety. A few methods of DNA isolation from milk have been reported, but many of them are time consuming and expensive. Here, we report a rapid, simple, and efficient method of mtDNA extraction from raw and processed milk (pasteurized, retorted, and UHT milk) to generate substrate for analysis using any PCR analysis platform. Various techniques used for the separation of mitochondria were explored and combined with a sodium dodecyl sulfate method for mtDNA extraction from raw and processed milk. The optimized protocol supports the efficient amplification of mtDNA independent of sample origin and is sufficiently straightforward to allow its widespread adoption by industry.


Assuntos
DNA Mitocondrial/isolamento & purificação , Laticínios/análise , Leite/química , Animais , Reação em Cadeia da Polimerase , Especificidade da Espécie
7.
Zhonghua Yi Xue Za Zhi ; 96(28): 2238-40, 2016 Jul 26.
Artigo em Chinês | MEDLINE | ID: mdl-27480656

RESUMO

OBJECTIVE: To compare the effectiveness and complications of TVT-Abbrevo (tension-free vaginal tape-Abbrevo) and TVT-Obturator (tension-free vaginal tape-obturator) for the treatment of female stress urinary incontinence (SUI). METHODS: From Nov.2012 to Nov.2013, 117 patients suffering from SUI were treated with TVT-Abbrebo (n=79) or TVT-Obturator (n=38) procedure, the clinical efficacy and operation-correlated complications were observed. RESULTS: A total of 117 cases, 107 cases of urinary incontinence symptoms disappeared completely, 10 cases were improved. 72 cases (91.1%) were cured and 7 cases (8.9%) were improved in TVT-Abbrevo group; 35 cases (92.1%) were cured and 3 cases (7.9%) were improved in TVT-Obturator group. No significant differences could be found for the curing rates between two groups (P>0.05). Compared with the TVT-Obturator group, the TVT-Abbrevo group had less patients complaining of inner thigh pain at 24 h and 1 w after surgery (P<0.05). No significant differences were observed for the incidence of inner thigh pain at 1m and 1y after surgery between TVT-Abbrevo and TVT-Obturator group (P>0.05). No intraoperative complications such as blood vessel, nerve, bladder damage were recorded and no postoperative retropubic hematoma, tape adjustment and other complications occurred in two goups. No recurrence after 1 year follow-up. CONCLUSIONS: The study shows that TVT-Abbrevo procedure is safe and efficacy in treatment of SUI, and associated with low incidence of recent postoperative inner thigh pain.


Assuntos
Procedimentos Cirúrgicos em Ginecologia/instrumentação , Slings Suburetrais , Fita Cirúrgica , Incontinência Urinária por Estresse/cirurgia , Procedimentos Cirúrgicos Urológicos/métodos , Vagina/cirurgia , Feminino , Procedimentos Cirúrgicos em Ginecologia/métodos , Humanos , Incidência , Complicações Intraoperatórias , Dor Pós-Operatória , Período Pós-Operatório , Recidiva , Resultado do Tratamento , Procedimentos Cirúrgicos Urológicos/instrumentação
8.
Genet Mol Res ; 14(4): 12733-45, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26505424

RESUMO

Black pepper is a perennial climbing vine. It is widely cultivated because its berries can be utilized not only as a spice in food but also for medicinal use. This study aimed to construct a standardized, high-quality cDNA library to facilitated identification of new Piper hainanense transcripts. For this, 262 unigenes were used to generate raw reads. The average length of these 262 unigenes was 774.8 bp. Of these, 94 genes (35.9%) were newly identified, according to the NCBI protein database. Thus, identification of new genes may broaden the molecular knowledge of P. hainanense on the basis of Clusters of Orthologous Groups and Gene Ontology categories. In addition, certain basic genes linked to physiological processes, which can contribute to disease resistance and thereby to the breeding of black pepper. A total of 26 unigenes were found to be SSR markers. Dinucleotide SSR was the main repeat motif, accounting for 61.54%, followed by trinucleotide SSR (23.07%). Eight primer pairs successfully amplified DNA fragments and detected significant amounts of polymorphism among twenty-one piper germplasm. These results present a novel sequence information of P. hainanense, which can serve as the foundation for further genetic research on this species.


Assuntos
Etiquetas de Sequências Expressas , Piper/genética , DNA de Plantas/genética , Regulação da Expressão Gênica de Plantas , Biblioteca Gênica , Genoma de Planta/genética , Polimorfismo Genético/genética
9.
Genet Mol Res ; 13(3): 6316-31, 2014 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-24782213

RESUMO

This study analyzed 394 Korean rice landrace accessions, including 93 waxy varieties, for polymorphisms using 29 simple sequence repeat (SSR) markers. In total, 381 alleles served as raw data for estimating the genetic diversity (GD) and population structure. The number of alleles per locus ranged from 3 to 44 (average = 13.14). The expected heterozygosity and polymorphism information content (PIC) ranged from 0.0341 to 0.9358 (mean = 0.5623) and from 0.0783 to 0.9367 (mean = 0.5839), respectively. The mean GDs in waxy, low amylose content, intermediate amylose content, and high amylose content (HAC) varieties were 0.6014, 0.5922, 0.5858, and 0.7232, respectively, whereas the mean PIC values for each SSR locus were 0.5701, 0.5594, 0.5550, and 0.6926, respectively. HAC varieties had the highest GD and PIC. Consistent with clustering by genetic distances, a model-based structural analysis revealed 3 subpopulations. Analysis of molecular variance revealed that the between-population component of genetic variance was 22.35%, and that of the within-population component was 77.65%. Significant correlations were observed between eating quality and protein content (r = -0.262), K(+) (r = -0.655), Mg(2+) (r = -0.680), 1000-GW (r = 0.159), and amylose content (r = -0.134). The overall FST value was 0.2235, indicating moderate differentiation among the groups. Analysis of variance of the 3 genetic groups (mean of 9 phenotypic and 5 physicochemical traits) by the Duncan multiple range test showed significant differences in 10 traits. This preliminary study represents a first step toward more efficient conservation and greater utilization of rice landraces to broaden the genetic bases of commercially grown varieties.


Assuntos
Oryza/genética , Polimorfismo Genético , Locos de Características Quantitativas , Característica Quantitativa Herdável , Alelos , Amilose/metabolismo , Frequência do Gene , Genótipo , Repetições de Microssatélites , Família Multigênica , Oryza/classificação , Oryza/metabolismo , Fenótipo , Proteínas de Plantas/metabolismo , República da Coreia
10.
Clin Genet ; 72(2): 87-97, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17661812

RESUMO

LAMBDA is a model that estimates the probability an Ashkenazi Jewish (AJ) woman carries an ancestral BRCA1 or BRCA2 mutation from her personal and family cancer history. LAMBDA is relevant to clinical practice, and its implementation does not require a computer. It was developed principally from Australian and UK data. We conducted a validation study using 1286 North American AJ women tested for the mutations 185delAG and 5382insC in BRCA1 and 6174delT in BRCA2. Most had a personal or family history of breast cancer. We observed 197 carriers. The area under the receiver operator characteristic (ROC) curve (a measure of ranking) was 0.79 [95% confidence interval (CI) = 0.77-0.81], similar to that for the model-generating data (0.78; 95% CI = 0.75-0.82). LAMBDA predicted 232 carriers (18% more than observed; p = 0.002) and was overdispersed (p = 0.009). The Bayesian computer program BRCAPRO gave a similar area under the ROC curve (0.78; 95% CI = 0.76-0.80), but predicted 367 carriers (86% more than observed; p < 0.0001), and was substantially overdispersed (p < 0.0001). Therefore, LAMBDA is comparable to BRCAPRO for ranking AJ women according to their probability of being a BRCA1 or BRCA2 mutation carrier and is more accurate than brcapro which substantially overpredicts carriers in this population.


Assuntos
Neoplasias da Mama/etnologia , Neoplasias da Mama/genética , Genes BRCA1 , Genes BRCA2 , Triagem de Portadores Genéticos/métodos , Judeus/genética , Modelos Estatísticos , Mutação , Adulto , Idoso , Feminino , Humanos , Modelos Logísticos , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Estados Unidos
11.
Cancer Res ; 61(22): 8062-7, 2001 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-11719428

RESUMO

Li Fraumeni Syndrome (LFS) is a multicancer phenotype, most commonly associated with germ-line mutations in TP53. In a kindred with LFS without an inherited TP53 mutation, we have previously reported a truncating mutation (1100delC) in CHK2, encoding a kinase that phosphorylates p53 on Ser(20). Here, we describe a CHK2 missense mutation (R145W) in another LFS family. This mutation destabilizes the encoded protein, reducing its half-life from >120 min to 30 min. This effect is abrogated by treatment of cells with a proteosome inhibitor, suggesting that CHK2(R145W) is targeted through this degradation pathway. Both 1100delC and R145W germ-line mutations in CHK2 are associated with loss of the wild-type allele in the corresponding tumor specimens, and neither tumor harbors a somatic TP53 mutation. Our observations support the functional significance of CHK2 mutations in rare cases of LFS and suggest that such mutations may substitute for inactivation of TP53.


Assuntos
Síndrome de Li-Fraumeni/genética , Mutação de Sentido Incorreto , Proteínas Quinases/genética , Proteínas Serina-Treonina Quinases , Adulto , Sequência de Bases , Quinase do Ponto de Checagem 2 , Neoplasias do Colo/genética , DNA Complementar/genética , Feminino , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Genes p53/genética , Humanos , Síndrome de Li-Fraumeni/enzimologia , Perda de Heterozigosidade , Masculino , Dados de Sequência Molecular , Linhagem , Proteínas Quinases/metabolismo , Células Tumorais Cultivadas
12.
Med Pediatr Oncol ; 37(4): 372-8, 2001 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11568901

RESUMO

BACKGROUND: Genetic testing for inherited predisposition to diverse cancers has recently become available as a clinical service. We conducted a follow-up study of the initial series of US families who underwent RB1 genetic testing to evaluate long-term effects of the service. PROCEDURE: We enrolled 52 of 71 eligible families who responded to a follow-up study questionnaire administered 3-10 years after receipt of their RB1 results. Each family had one proband with unilateral, non-familial retinoblastoma, which is associated with a 12% pre-test probability of hereditary retinoblastoma. RB1 testing identified germline RB1 mutations in five patients, lowered the carrier probability to 2% in 21 patients, and did not substantially modify the carrier probability in the remaining 26. RESULTS: Diverse medical specialists offered and arranged for RB1 testing, and their recommendation was the most influential factor in the decision to be tested. Pre-test counseling was provided by ophthalmologists (30), oncologists (11), and geneticists and genetic counselors (11). Most respondents, regardless of test result, were satisfied and perceived gains from their genetic testing. Based on small numbers, families with reduced likelihood of hereditary retinoblastoma reported more positive outcomes. Parents of RB1 carriers were more likely to seek medical services, worry, and decide against having more children. CONCLUSIONS: This study demonstrates the feasibility of follow-up studies of families who had genetic testing. Results from our small series suggest that genetic information and counseling are important components of RB1 clinical genetic testing, and long-term adverse effects of testing are uncommon.


Assuntos
Genes do Retinoblastoma/genética , Testes Genéticos , Acessibilidade aos Serviços de Saúde/estatística & dados numéricos , Neoplasias da Retina/genética , Retinoblastoma/genética , Adulto , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Masculino , Neoplasias da Retina/diagnóstico , Retinoblastoma/diagnóstico , Estudos de Amostragem , Sensibilidade e Especificidade , Inquéritos e Questionários , Estados Unidos
13.
J Clin Oncol ; 19(5): 1462-7, 2001 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-11230492

RESUMO

PURPOSE: Mammograms and breast examinations are established methods for early breast cancer detection. Routine mammography screening reduces breast cancer mortality among women ages > or = 50 years, but additional screening methods are needed. We and others have found high levels of carcinoembryonic antigen (CEA) and prostate-specific antigen (PSA) in nipple aspirate fluids (NAFs), but the usefulness for these bio-markers for early breast cancer detection is unknown. PATIENTS AND METHODS: NAFs from one or both breasts of 388 women were analyzed for CEA, PSA, and albumin levels. The study included 44 women with newly diagnosed invasive breast cancers, 67 women with proliferative breast lesions (ductal and lobular carcinoma in situ and atypical ductal hyperplasia), and 277 controls without these breast lesions. Analyses were conducted using the log(10)-transformed CEA and PSA levels to normalize the distributions of these tumor markers. RESULTS: Nipple fluid CEAs are significantly higher for cancerous breasts than tumor-free breasts (median 1,830 and 1,400 ng/mL, respectively; P <.01). However, at 90% specificity of the assay (CEA = 11,750 ng/mL), the corresponding sensitivity for cancer detection is 32%. CEA levels are not significantly different for breasts with proliferative lesions compared with tumor-free breasts. Nipple fluid PSAs do not differ by tumor status. Analyses of NAF albumin-standardized CEAs and PSAs yield similar results. Nipple fluid CEA and PSA titers are correlated in the affected and unaffected breast of women with unilateral lesions. CONCLUSION: Nipple fluid CEAs are higher for breasts with untreated invasive cancers, but the test sensitivity is low. Nipple fluid PSA titers do not seem to be useful for breast cancer detection.


Assuntos
Biomarcadores Tumorais/análise , Neoplasias da Mama/diagnóstico , Antígeno Carcinoembrionário/análise , Antígeno Prostático Específico/análise , Adulto , Idoso , Neoplasias da Mama/imunologia , Feminino , Humanos , Inalação , Pessoa de Meia-Idade , Mamilos , Valor Preditivo dos Testes , Sensibilidade e Especificidade
14.
Cancer Epidemiol Biomarkers Prev ; 10(2): 83-7, 2001 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11219776

RESUMO

Germ-line p53 mutations are associated with dominantly inherited Li-Fraumeni syndrome (LFS), which features early-onset sarcomas of bone and soft tissues, carcinomas of the breast and adrenal cortex, brain tumors, and acute leukemias. However, carriers of germ-line p53 mutations may also be at increased risk of other cancers. To clarify the tumor spectrum associated with inherited p53 mutations, we examined cancer occurrences among our series of 45 families, plus 140 other affected cases and kindreds reported in the literature. The analyses included all cancers in patients with a germ-line p53 mutation and their first-degree relatives with nearly 50% likelihood of being a carrier. Data were abstracted on tumor types and ages at diagnosis in eligible family members, and duplicate reports were excluded. Among 738 evaluable cancers, 569 (77%) were the six tumor types (breast and adrenocortical carcinomas, sarcomas of the bone and soft tissues, brain tumors, and leukemias) associated with LFS. The remaining 169 (23%) cancers included diverse carcinomas of the lung and gastrointestinal tract, lymphomas, and other neoplasms that occurred at much earlier ages than expected in the general population. Unusually early ages at diagnosis are characteristic of hereditary cancers and suggest that carriers of germ-line p53 mutations are at increased risk of a wide range of neoplasms. Future studies addressing age-specific penetrance and site-specific cancer risks can increase the utility of LFS as a model for understanding the role of p53 alterations in carcinogenesis and for designing diagnostic and preventive interventions for the broad array of neoplasms in this syndrome.


Assuntos
Genes p53/genética , Predisposição Genética para Doença/epidemiologia , Heterozigoto , Mutação , Neoplasias/epidemiologia , Neoplasias/genética , Adolescente , Adulto , Distribuição por Idade , Idade de Início , Idoso , Feminino , Testes Genéticos/métodos , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Medição de Risco , Distribuição por Sexo , Taxa de Sobrevida
16.
Oncogene ; 19(37): 4230-5, 2000 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-10980596

RESUMO

Germline mutations in the p53 tumor suppressor gene predispose to a variety of cancers in families with Li-Fraumeni syndrome. Most germline p53 mutations observed to date cause amino acid substitutions in the protein's central sequence-specific DNA binding domain. Outside this conserved core region, however, we found novel alterations in sequences that regulate precursor mRNA splicing in three Li-Fraumeni syndrome families. Two splice site mutations affected the consensus sequence at the splice donor sites of introns 1 and 9, and produced unstable variant transcripts in normal cells. A third mutation at the splice acceptor site of intron 9 generated splicing at a cryptic acceptor site in intron 9. These splice site alterations emphasize the need to examine both noncoding and untranslated regions of the p53 gene for germline mutations in Li-Fraumeni syndrome families. Oncogene (2000) 19, 4230 - 4235


Assuntos
Genes p53 , Síndrome de Li-Fraumeni/genética , Splicing de RNA/genética , Sequência de Bases , Células Cultivadas/metabolismo , Códon/genética , Sequência Consenso , Análise Mutacional de DNA , Feminino , Genótipo , Humanos , Íntrons/genética , Queratinócitos/metabolismo , Masculino , Dados de Sequência Molecular , Linhagem , RNA Mensageiro/genética
19.
Mol Cell Biol ; 20(4): 1436-47, 2000 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-10648628

RESUMO

Normal human cells exhibit a limited replicative life span in culture, eventually arresting growth by a process termed senescence. Progressive telomere shortening appears to trigger senescence in normal human fibroblasts and retinal pigment epithelial cells, as ectopic expression of the telomerase catalytic subunit, hTERT, immortalizes these cell types directly. Telomerase expression alone is insufficient to enable certain other cell types to evade senescence, however. Such cells, including keratinocytes and mammary epithelial cells, appear to require loss of the pRB/p16(INK4a) cell cycle control mechanism in addition to hTERT expression to achieve immortality. To investigate the relationships among telomerase activity, cell cycle control, senescence, and differentiation, we expressed hTERT in two epithelial cell types, keratinocytes and mesothelial cells, and determined the effect on proliferation potential and on the function of cell-type-specific growth control and differentiation systems. Ectopic hTERT expression immortalized normal mesothelial cells and a premalignant, p16(INK4a)-negative keratinocyte line. In contrast, when four keratinocyte strains cultured from normal tissue were transduced to express hTERT, they were incompletely rescued from senescence. After reaching the population doubling limit of their parent cell strains, hTERT(+) keratinocytes entered a slow growth phase of indefinite length, from which rare, rapidly dividing immortal cells emerged. These immortal cell lines frequently had sustained deletions of the CDK2NA/INK4A locus or otherwise were deficient in p16(INK4a) expression. They nevertheless typically retained other keratinocyte growth controls and differentiated normally in culture and in xenografts. Thus, keratinocyte replicative potential is limited by a p16(INK4a)-dependent mechanism, the activation of which can occur independent of telomere length. Abrogation of this mechanism together with telomerase expression immortalizes keratinocytes without affecting other major growth control or differentiation systems.


Assuntos
Senescência Celular/fisiologia , Inibidor p16 de Quinase Dependente de Ciclina/metabolismo , Queratinócitos/citologia , Queratinócitos/metabolismo , RNA , Telomerase/metabolismo , Diferenciação Celular , Divisão Celular , Linhagem Celular , Transformação Celular Neoplásica , Senescência Celular/genética , Inibidor p16 de Quinase Dependente de Ciclina/genética , Proteínas de Ligação a DNA , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Deleção de Genes , Expressão Gênica , Genes p53 , Teste de Complementação Genética , Humanos , Mutação , Telomerase/genética
20.
J Med Genet ; 36(10): 747-53, 1999 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-10528853

RESUMO

The hereditary breast and ovarian cancer syndrome is associated with a high frequency of BRCA1 mutations. However, the widespread use of BRCA1 testing has been limited to date by three principal concerns: the fear of loss of health and life insurance, the uncertain clinical value of a positive test result, and the current lack of an inexpensive and sensitive screening test for BRCA1 mutations. We have developed an inexpensive system for gene mutational scanning, based on a combination of extensive multiplex PCR amplification and two dimensional electrophoresis. The efficiency of this system, as a screening test for BRCA1 mutations, was evaluated in a panel of 60 samples from high risk women, 14 of which contained a previously identified mutation in BRCA1. All 14 mutations were identified, as well as an additional five that had previously escaped detection. In addition to the 19 mutations, a total of 15 different polymorphic variants were scored, most of which were recurring. All were confirmed by nucleotide sequencing. The cost of screening per sample was calculated to be approximately US$70 for the manual technique used in this study, and may be reduced to approximately US$10 with the introduction of commercially available PCR robotics and fluorescent imaging. Implementation of this method of mutation screening in the research and clinical setting should permit rapid accrual of quantitative data on genotype-phenotype associations for the evaluation of diagnostic testing.


Assuntos
Genes BRCA1/genética , Testes Genéticos/métodos , Neoplasias da Mama/genética , Análise Mutacional de DNA/economia , Análise Mutacional de DNA/métodos , Eletroforese em Gel Bidimensional , Éxons , Feminino , Testes Genéticos/economia , Humanos , Masculino , Modelos Genéticos , Neoplasias/genética , Reação em Cadeia da Polimerase , Polimorfismo Genético , Reprodutibilidade dos Testes , Análise de Sequência de DNA
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