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2.
Methods Mol Biol ; 1896: 119-138, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30474845

RESUMO

Lipofuscin accumulation is a hallmark of senescence. This nondegradable material aggregates in the cytoplasm of stressed or damaged cells due to metabolic imbalance associated with aging and age-related diseases. Indications of a soluble state of lipofuscin have also been provided, rendering the perspective of monitoring such processes via lipofuscin quantification in liquids intriguing. Therefore, the development of an accurate and reliable method is of paramount importance. Currently available assays are characterized by inherent pitfalls which demote their credibility. We herein describe a simple, highly specific and sensitive protocol for measuring lipofuscin levels in any type of liquid. The current method represents an evolution of a previously described assay, developed for in vitro and in vivo senescent cell recognition that exploits a newly synthesized Sudan Black-B analog (GL13). Analysis of human clinical samples with the modified protocol provided strong evidence of its usefulness for the exposure and surveillance of age-related conditions.


Assuntos
Envelhecimento , Compostos Azo , Biomarcadores/sangue , Senescência Celular , Lipofuscina/sangue , Naftalenos , Adulto , Idoso , Idoso de 80 Anos ou mais , Humanos , Pessoa de Meia-Idade , Coloração e Rotulagem , Adulto Jovem
3.
Aging Cell ; 16(1): 192-197, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-28165661

RESUMO

Cellular senescence contributes to organismal development, aging, and diverse pathologies, yet available assays to detect senescent cells remain unsatisfactory. Here, we designed and synthesized a lipophilic, biotin-linked Sudan Black B (SBB) analogue suitable for sensitive and specific, antibody-enhanced detection of lipofuscin-containing senescent cells in any biological material. This new hybrid histo-/immunochemical method is easy to perform, reliable, and universally applicable to assess senescence in biomedicine, from cancer research to gerontology.


Assuntos
Bioensaio/métodos , Biomarcadores/análise , Senescência Celular , Animais , Biotina/metabolismo , Linhagem Celular Tumoral , Humanos , Camundongos
4.
Carcinogenesis ; 35(6): 1267-75, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24523449

RESUMO

Human papillomavirus (HPV) is the etiologic risk factor for cervical cancer. Some studies have suggested an association with a subset of lung tumors, but the etiologic link has not been firmly established. We performed an international pooled analysis of cross-sectional studies (27 datasets, n = 3249 patients) to evaluate HPV DNA prevalence in lung cancer and to investigate viral presence according to clinical and demographic characteristics. HPV16/18 were the most commonly detected, but with substantial variation in viral prevalence between geographic regions. The highest prevalence of HPV16/18 was observed in South and Central America, followed by Asia, North America and Europe (adjusted prevalence rates = 22, 5, 4 and 3%, respectively). Higher HPV16 prevalence was noted in each geographic region compared with HPV18, except in North America. HPV16/18-positive lung cancer was less likely observed among White race (adjusted odds ratio [OR] = 0.33, 95% confidence interval [CI] = 0.12-0.90), whereas no associations were observed with gender, smoking history, age, histology or stage. Comparisons between tumor and normal lung tissue show that HPV was more likely to be present in lung cancer rather than normal lung tissues (OR = 3.86, 95% CI = 2.87-5.19). Among a subset of patients with HPV16-positive tumors, integration was primarily among female patients (93%, 13/14), while the physical status in male cases (N = 14) was inconsistent. Our findings confirm that HPV DNA is present in a small fraction of lung tumors, with large geographic variations. Further comprehensive analysis is needed to assess whether this association reflects a causal relationship.


Assuntos
Alphapapillomavirus/genética , Neoplasias Pulmonares/etiologia , Infecções por Papillomavirus/complicações , Idoso , Idoso de 80 Anos ou mais , Feminino , Genótipo , Papillomavirus Humano 16/genética , Papillomavirus Humano 18/genética , Humanos , Neoplasias Pulmonares/epidemiologia , Neoplasias Pulmonares/virologia , Masculino , Pessoa de Meia-Idade , Infecções por Papillomavirus/epidemiologia , Prevalência , Integração Viral
5.
Urology ; 66(3): 536-41, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16140073

RESUMO

OBJECTIVES: To investigate whether immunocytochemical detection of cytokeratin (CK)-20 could serve as a reliable diagnostic marker for transitional cell carcinoma (TCC) of the bladder. METHODS: A total of 232 patients were enrolled in the study. Group 1 consisted of 144 patients with histologically confirmed TCC (62 at diagnosis and 82 in follow-up), and group 2 consisted of 88 subjects, including healthy volunteers and individuals with "non-TCC" conditions. Spontaneously voided urine specimens were obtained from each patient and submitted to immunocytologic and standard cytologic examination. RESULTS: CK-20 immunocytology yielded an overall sensitivity of 65.3%, significantly greater than the sensitivity of urine cytology (54.2%, P = 0.013). A more detailed analysis revealed a sensitivity advantage for the former technique in the detection of primary (61.3% versus 51.6%, P = 0.046), recurrent (68.3% versus 56.1%, P = 0.027), Stage pT1 (81.8% versus 59.1%, P = 0.006), grade 2 (76.2% versus 61.9%, P = 0.031), and grade 3 (82.1% versus 67.9%, P = 0.039) tumors. Moreover, CK-20 immunocytochemistry demonstrated greater overall specificity than cytology (90.9% versus 86.4%, respectively), a difference stemming from the subgroup of lithiasis patients (100% versus 66.7%, P = 0.024). In terms of reliability, the positive and negative predictive values of the immunoassay were greater than those calculated for cytology (92.2% versus 86.7% and 61.5% versus 53.5%, respectively). CONCLUSIONS: CK-20 immunocytology is more sensitive than standard cytology in the detection of TCC, particularly of Stage pT1, grade 2, and grade 3 tumors. In view of its high overall specificity and predictive accuracy, it is conceivable that the proposed immunoassay may progressively replace conventional cytologic screening in the diagnosis of bladder cancer.


Assuntos
Carcinoma de Células de Transição/patologia , Neoplasias da Bexiga Urinária/patologia , Biomarcadores Tumorais , Feminino , Humanos , Proteínas de Filamentos Intermediários , Queratina-20 , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
6.
Nature ; 434(7035): 907-13, 2005 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-15829965

RESUMO

DNA damage checkpoint genes, such as p53, are frequently mutated in human cancer, but the selective pressure for their inactivation remains elusive. We analysed a panel of human lung hyperplasias, all of which retained wild-type p53 genes and had no signs of gross chromosomal instability, and found signs of a DNA damage response, including histone H2AX and Chk2 phosphorylation, p53 accumulation, focal staining of p53 binding protein 1 (53BP1) and apoptosis. Progression to carcinoma was associated with p53 or 53BP1 inactivation and decreased apoptosis. A DNA damage response was also observed in dysplastic nevi and in human skin xenografts, in which hyperplasia was induced by overexpression of growth factors. Both lung and experimentally-induced skin hyperplasias showed allelic imbalance at loci that are prone to DNA double-strand break formation when DNA replication is compromised (common fragile sites). We propose that, from its earliest stages, cancer development is associated with DNA replication stress, which leads to DNA double-strand breaks, genomic instability and selective pressure for p53 mutations.


Assuntos
Dano ao DNA , Instabilidade Genômica/genética , Lesões Pré-Cancerosas/patologia , Lesões Pré-Cancerosas/prevenção & controle , Desequilíbrio Alélico/genética , Apoptose , Linhagem Celular Tumoral , Transformação Celular Neoplásica/genética , Quinase do Ponto de Checagem 2 , Fragilidade Cromossômica , Dano ao DNA/genética , Replicação do DNA , Progressão da Doença , Ativação Enzimática , Genes p53/genética , Histonas/metabolismo , Humanos , Hiperplasia/enzimologia , Hiperplasia/genética , Hiperplasia/metabolismo , Hiperplasia/patologia , Peptídeos e Proteínas de Sinalização Intracelular/metabolismo , Mutação/genética , Fosfoproteínas/metabolismo , Fosforilação , Lesões Pré-Cancerosas/enzimologia , Lesões Pré-Cancerosas/genética , Proteínas Serina-Treonina Quinases/metabolismo , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Proteína 1 de Ligação à Proteína Supressora de Tumor p53
7.
Am J Pathol ; 165(4): 1351-65, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15466399

RESUMO

Replication licensing ensures once per cell cycle replication and is essential for genome stability. Overexpression of two key licensing factors, Cdc6 and Cdt1, leads to overreplication and chromosomal instability (CIN) in lower eukaryotes and recently in human cell lines. In this report, we analyzed hCdt1, hCdc6, and hGeminin, the hCdt1 inhibitor expression, in a series of non-small-cell lung carcinomas, and investigated for putative relations with G(1)/S phase regulators, tumor kinetics, and ploidy. This is the first study of these fundamental licensing elements in primary human lung carcinomas. We herein demonstrate elevated levels (more than fourfold) of hCdt1 and hCdc6 in 43% and 50% of neoplasms, respectively, whereas aberrant expression of hGeminin was observed in 49% of cases (underexpression, 12%; overexpression, 37%). hCdt1 expression positively correlated with hCdc6 and E2F-1 levels (P = 0.001 and P = 0.048, respectively). Supportive of the observed link between E2F-1 and hCdt1, we provide evidence that E2F-1 up-regulates the hCdt1 promoter in cultured mammalian cells. Interestingly, hGeminin overexpression was statistically related to increased hCdt1 levels (P = 0.025). Regarding the kinetic and ploidy status of hCdt1- and/or hCdc6-overexpressing tumors, p53-mutant cases exhibited significantly increased tumor growth values (Growth Index; GI) and aneuploidy/CIN compared to those bearing intact p53 (P = 0.008 for GI, P = 0.001 for CIN). The significance of these results was underscored by the fact that the latter parameters were independent of p53 within the hCdt1-hCdc6 normally expressing cases. Cumulatively, the above suggest a synergistic effect between hCdt1-hCdc6 overexpression and mutant-p53 over tumor growth and CIN in non-small-cell lung carcinomas.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/metabolismo , Proteínas de Ciclo Celular/biossíntese , Neoplasias Pulmonares/metabolismo , Idoso , Animais , Apoptose/fisiologia , Western Blotting , Carcinoma Pulmonar de Células não Pequenas/patologia , Proteínas Cdh1 , Ciclo Celular/fisiologia , Proteínas de Ligação a DNA/biossíntese , Fatores de Transcrição E2F , Fator de Transcrição E2F1 , Imunofluorescência , Geminina , Humanos , Marcação In Situ das Extremidades Cortadas , Perda de Heterozigosidade , Neoplasias Pulmonares/patologia , Camundongos , Pessoa de Meia-Idade , Células NIH 3T3 , Proteínas Nucleares , Ploidias , Polimorfismo Conformacional de Fita Simples , Prognóstico , Regiões Promotoras Genéticas , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Fatores de Transcrição/biossíntese , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo , Regulação para Cima
8.
Anticancer Res ; 22(1A): 347-74, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-12017316

RESUMO

This review aims in presenting the established and putative prognostic markers in non-small cell lung carcinoma (NSCLC). We have focused on the molecular/genetic alterations accompanying the pathogenesis of this malignancy, which may derange the cellular response to external and internal stimuli. A variety of factors influencing cell cycle progression, programmed cell death, drug resistance and immune evasion seem to obtain a predictive--though sometimes argued--role. Taking into account that a great number of these factors develope "cross-talking" protein-complex networks, their combined evaluation is likely to contribute towards a more accurate prediction of the clinical outcome in NSCLC patients.


Assuntos
Carcinoma Pulmonar de Células não Pequenas/diagnóstico , Neoplasias Pulmonares/diagnóstico , Carcinoma Pulmonar de Células não Pequenas/genética , Carcinoma Pulmonar de Células não Pequenas/metabolismo , Carcinoma Pulmonar de Células não Pequenas/patologia , Humanos , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/metabolismo , Neoplasias Pulmonares/patologia , Prognóstico
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