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1.
Lab Invest ; 88(7): 694-721, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18458673

RESUMEN

The search for the genomic sequences involved in human cancers can be greatly facilitated by maps of genomic imbalances identifying the involved chromosomal regions, particularly those that participate in the development of occult preneoplastic conditions that progress to clinically aggressive invasive cancer. The integration of such regions with human genome sequence variation may provide valuable clues about their overall structure and gene content. By extension, such knowledge may help us understand the underlying genetic components involved in the initiation and progression of these cancers. We describe the development of a genome-wide map of human bladder cancer that tracks its progression from in situ precursor conditions to invasive disease. Testing for allelic losses using a genome-wide panel of 787 microsatellite markers was performed on multiple DNA samples, extracted from the entire mucosal surface of the bladder and corresponding to normal urothelium, in situ preneoplastic lesions, and invasive carcinoma. Using this approach, we matched the clonal allelic losses in distinct chromosomal regions to specific phases of bladder neoplasia and produced a detailed genetic map of bladder cancer development. These analyses revealed three major waves of genetic changes associated with growth advantages of successive clones and reflecting a stepwise conversion of normal urothelial cells into cancer cells. The genetic changes map to six regions at 3q22-q24, 5q22-q31, 9q21-q22, 10q26, 13q14, and 17p13, which may represent critical hits driving the development of bladder cancer. Finally, we performed high-resolution mapping using single nucleotide polymorphism markers within one region on chromosome 13q14, containing the model tumor suppressor gene RB1, and defined a minimal deleted region associated with clonal expansion of in situ neoplasia. These analyses provided new insights on the involvement of several non-coding sequences mapping to the region and identified novel target genes, termed forerunner (FR) genes, involved in early phases of cancer development.


Asunto(s)
Carcinoma de Células Transicionales/genética , Mapeo Cromosómico , Neoplasias de la Vejiga Urinaria/genética , Anciano , Cromosomas Humanos Par 13/genética , Humanos , Masculino , Repeticiones de Microsatélite , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Proteína de Retinoblastoma/genética , Vejiga Urinaria/metabolismo , Vejiga Urinaria/patología , Urotelio/metabolismo , Urotelio/patología
2.
Cancer Genet Cytogenet ; 175(2): 117-24, 2007 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-17556067

RESUMEN

Chromosome anomalies have been shown to have prognostic significance in children with acute lymphoblastic leukemia (ALL). Chromosome 21 was evaluated for its ability to predict outcome when found in either a single copy (the Mono21 group) or when involved in a structural aberration (the Misc21 group). Both anomalies were associated with an increased risk of failure for patients with standard-risk ALL, rather than higher-risk ALL. Event-free survival was 50.0% at 5 years and 48.4% at 8 years for standard-risk patients with Mono21+Misc21, compared with 77.8 and 75.5%, respectively, for standard-risk patients without these anomalies of chromosome 21. There was no significant difference in outcome between the Mono21 and the Misc21 group (P = 0.10). Mono21 and Misc21 were determined to be independently prognostic whether or not the primary leukemic clone had fewer than 45 chromosomes. The frequency of an adverse outcome was comparable to other poor prognosis subgroups such as hypodiploidy (<45 chromosomes), t(9;22), or t(4;11), all of which have been targeted for aggressive therapy even if the case is otherwise standard risk.


Asunto(s)
Aberraciones Cromosómicas , Cromosomas Humanos Par 21/genética , Análisis Citogenético , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Pronóstico
3.
Clin Cancer Res ; 11(15): 5417-24, 2005 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16061856

RESUMEN

PURPOSE: The present study was conducted to determine clinical relevance of surfactant protein A (SP-A) genetic aberrations in early-stage non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: To determine whether SP-A aberrations are lung cancer-specific and indicate smoking-related damage, tricolor fluorescence in situ hybridization with SP-A and PTEN probes was done on touch imprints from the lung tumors obtained prospectively from 28 patients with primary NSCLC. To further define the clinical relevance of SP-A aberrations, fluorescence in situ hybridization was done on both tumor cells and adjacent bronchial tissue cells from paraffin-embedded tissue blocks from 130 patients NSCLC for whom we had follow-up information. RESULTS: SP-A was deleted from 89% of cancer tissues and the deletion was related to the smoking status of patients (P < 0.001). PTEN was deleted from 16% in the cancer tissues and the deletion was not related to the smoking status of patients (P > 0.05). In the cells isolated from paraffin-embedded tissue blocks, SP-A was deleted from 87% of the carcinoma tissues and 32% of the adjacent normal-appearing bronchial tissues. SP-A deletions in tumors and adjacent normal-appearing bronchial tissues were associated with increases in the risk of disease relapse (P = 0.0035 and P < 0.001, respectively). SP-A deletions in the bronchial epithelium were the strongest prognostic indicators of disease-specific survival (P = 0.025). CONCLUSIONS: Deletions of the SP-A gene are specific genomic aberrations in bronchial epithelial cells adjacent to and within NSCLC, and are associated with tumor progression and a history of smoking. SP-A deletions might be a useful biomarker to identify poor prognoses in patients with NSCLC who might therefore benefit from adjuvant treatment.


Asunto(s)
Carcinoma de Pulmón de Células no Pequeñas/genética , Eliminación de Gen , Neoplasias Pulmonares/genética , Proteína A Asociada a Surfactante Pulmonar/genética , Biomarcadores de Tumor , Carcinoma/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/mortalidad , Carcinoma de Pulmón de Células no Pequeñas/patología , Línea Celular Tumoral , Supervivencia sin Enfermedad , Femenino , Humanos , Hibridación in Situ , Hibridación Fluorescente in Situ , Neoplasias Pulmonares/mortalidad , Neoplasias Pulmonares/patología , Masculino , Pronóstico , Modelos de Riesgos Proporcionales , Recurrencia , Fumar , Factores de Tiempo
4.
Genetics ; 168(1): 363-72, 2004 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-15454549

RESUMEN

Interspecies hybrids between distinct species of the genus Xiphophorus are often used in varied research investigations to identify genomic regions associated with the inheritance of complex traits. There are 24 described Xiphophorus species and a greater number of pedigreed strains; thus, the number of potential interspecies hybrid cross combinations is quite large. Previously, select Xiphophorus experimental crosses have been shown to exhibit differing characteristics between parental species and among the hybrid fishes derived from crossing them, such as widely differing susceptibilities to chemical or physical agents. For instance, genomic regions harboring tumor suppressor and oncogenes have been identified via linkage association of these loci with a small set of established genetic markers. The power of this experimental strategy is related to the number of genetic markers available in the Xiphophorus interspecies cross of interest. Thus, we have undertaken the task of expanding the suite of easily scored markers by characterization of Xiphophorus microsatellite sequences. Using a cross between Xiphophorus maculatus and X. andersi, we report a linkage map predominantly composed of microsatellite markers. All 24 acrocentric chromosome sets of Xiphophorus are represented in the assembled linkage map with an average intergenomic distance of 7.5 cM. Since both male and female F1 hybrids were used to produce backcross progeny, these recombination rates were compared between "male" and "female" maps. Although several genomic regions exhibit differences in map length, male- and female-derived maps are similar. Thus Xiphophorus, in contrast to zebrafish, Danio rerio, and several other vertebrate species, does not show sex-specific differences in recombination. The microsatellite markers we report can be easily adapted to any Xiphophorus interspecies and some intraspecies crosses, and thus provide a means to directly compare results derived from independent experiments.


Asunto(s)
Mapeo Cromosómico , Ciprinodontiformes/genética , Genoma , Hibridación Genética , Repeticiones de Microsatélite/genética , Animales , Cartilla de ADN , Electroforesis en Gel de Agar , Femenino , Isoenzimas , Masculino
5.
Med Phys ; 32(1): 182-94, 2005 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-15719969

RESUMEN

Full-field digital mammography systems are currently available for clinical use. These digital systems offer improved image quality, flexible image processing, display, storage, retrieval, and transmission. These systems employ a variety of different x-ray detectors based on storage phosphors (in computed radiography), charge-coupled devices (CCDs), or amorphous silicon flat panels (FPs). The objective of this study is to compare three different types of mammographic detectors: screenfilm (SF) combination, a CsI-based FP detector, a CCD and x-ray phosphor-based detector for their performance in detection of simulated microcalcifications. Microcalcifications (MCs) were simulated with calcium carbonate grains of various sizes (90-355 microm). They were overlapped with a slab of simulated 50% adipose/50% glandular breast tissue for a uniform background or an anthropomorphic breast phantom for a tissue structure background. Images of the phantoms, acquired with and without magnification, were reviewed by mammographers, physicists, and students. A five-point confidence level rating was given for each MC reviewed. Average ratings from the mammographers were used to compare the performances of the three imaging systems, various MC size groups, and two magnification modes. The results indicate that with uniform background and no magnification, the FP system performed the best while the SF system did slightly better than the CCD system. With magnification added, all detection tasks were improved except for the smallest and largest one or two size groups. In particular, detection in the SF and CCD images was significantly improved over that in the FP images. With tissue structure background and no magnification, the FP system was outperformed by the SF and the CCD systems. With magnification added, the performance of the FP and the CCD systems was improved significantly. With this improvement, the SF and FP systems were outperformed by the CCD system.


Asunto(s)
Neoplasias de la Mama/diagnóstico , Procesamiento de Imagen Asistido por Computador/métodos , Mamografía/instrumentación , Mamografía/métodos , Mama/patología , Enfermedades de la Mama/diagnóstico , Calcinosis , Carbonato de Calcio/química , Humanos , Fantasmas de Imagen , Intensificación de Imagen Radiográfica , Magnificación Radiográfica , Reproducibilidad de los Resultados , Programas Informáticos , Pantallas Intensificadoras de Rayos X , Rayos X
6.
Oncol Res ; 15(1): 49-57, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15839305

RESUMEN

The STK15 (also known as Aurora-A/BTAK) gene localized on chromosome 20q13 and encoding a centrosome-associated serine/threonine kinase is amplified and overexpressed in multiple human tumor cell types. Overexpression of this gene is involved in tumorigenic transformation, induction of centrosome duplication-distribution abnormalities, and aneuploidy in mammalian cells. To examine the potential role of STK15 in ovarian tumorigenesis, its mRNA and protein expression status were examined in cells grown in culture from 15 ovarian cancer specimens using semiquantitative RT-PCR and Western blot analysis. Normal ovarian surface tissues and the near diploid nontumorigenic breast epithelial cell line MCF10 were used as controls. The status of STK15 correlated with transformation-associated cellular phenotypes including tumorigenicity in nude mice, p53 expression level, and chromosomal ploidy. For chromosome ploidy analyses, FISH was carried out with direct fluorescence-labeled a-satellite probes for chromosome 3 and 17. STK15 mRNA was found overexpressed in 10 of the 15 ovarian cancer cell cultures. Five of these cell cultures revealed a truncated form of the STK15 protein with a molecular mass of 36 kDa. When tested for tumorigenicity in nude mice, 9 of the 10 cell cultures that overexpressed STK15 mRNA formed tumors in nude mice, while only one of the five cell cultures with no overexpression did. Cells overexpressing STK15 mRNA showed significant correlation with chromosome 3 polysomy. Six of the 13 (46%) cell cultures analyzed for p53 expression revealed overexpression of p53 and five of these six (83%) also overexpressed STK15. Four of the remaining seven cultures (57%) with overexpression of STK15 revealed minimal or no expression of p53. These results demonstrate that overexpression of STK15 significantly correlates with nude mice tumorigenicity and chromosomal aneuploidy in human ovarian cancer cells grown in vitro. Additionally, cells overexpressing STK15 also revealed frequent coordinate loss of wild-type p53 function manifested either as highly expressed intense staining reflective of a mutant form of p53 or almost complete absence of p53 staining. Overexpression of STK15 with coordinate loss of wild-type p53 function thus appears to play an important role in ovarian tumorigenesis and offers a novel molecular target in designing effective therapy of human ovarian cancer.


Asunto(s)
Transformación Celular Neoplásica/genética , Inestabilidad Cromosómica , Perfilación de la Expresión Génica , Genes p53 , Neoplasias Ováricas/genética , Proteínas Serina-Treonina Quinasas/biosíntesis , Aneuploidia , Animales , Aurora Quinasa A , Aurora Quinasas , Análisis Mutacional de ADN , Femenino , Humanos , Inmunohistoquímica , Hibridación Fluorescente in Situ , Ratones , Ratones Desnudos , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Células Tumorales Cultivadas , Regulación hacia Arriba
7.
Clin Cancer Res ; 8(3): 775-81, 2002 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11895908

RESUMEN

The molecular events leading to progression toward androgen-independent prostate cancer (AIPC) are not fully understood. The p21((WAF-1/CIP1)) (p21) gene has been identified as a key factor for the regulation of cell growth. The expression of p21 was examined by immunohistochemical studies in 105 prostate cancer samples: (a) 7 of 30 (23%) androgen-dependent tumors; and (b) 36 of 75 (48%) androgen-independent tumors stained positive for p21 (P < 0.02). No association was found between p21 expression and p53, bcl-2, and the androgen receptor protein expression in bone metastases of patients with AIPC, whereas there was a significant association with a high Ki-67 index (P < 0.05). In 4 of 43 (9%) cases, tumors displayed a p53-negative, bcl-2-negative, and p21-positive phenotype. A xenograft mouse model of prostate cancer using the androgen-responsive MDA PCa 2b prostate cancer cell line was used to study p21 expression after androgen deprivation and at relapse. Androgen deprivation reduced p21 expression to undetectable levels after 14 days. Tumor relapse, defining AIPC, was associated with increased expression of p21 to levels comparable with those found before castration. In this model, p21 expression at relapse was also correlated with a high Ki-67 index. In conclusion, p21 expression is associated with the progression to AIPC. A possible explanation involves a paracrine effect of p21 mediated by the release of mitogenic and antiapoptotic factors. Another explanation involves the regulation of p21 expression by the androgen receptor, which also suggests that p21 may have antiapoptotic function in prostate cancer.


Asunto(s)
Ciclinas/metabolismo , Regulación Neoplásica de la Expresión Génica/genética , Neoplasias de la Próstata/metabolismo , Andrógenos/farmacología , Animales , Biopsia , Neoplasias Óseas/metabolismo , Neoplasias Óseas/patología , Neoplasias Óseas/secundario , Inhibidor p21 de las Quinasas Dependientes de la Ciclina , Ciclinas/genética , Progresión de la Enfermedad , Humanos , Técnicas para Inmunoenzimas , Antígeno Ki-67/metabolismo , Masculino , Ratones , Ratones Desnudos , Recurrencia Local de Neoplasia/metabolismo , Recurrencia Local de Neoplasia/patología , Estadificación de Neoplasias , Neoplasias Experimentales/metabolismo , Neoplasias Experimentales/patología , Neoplasias de la Próstata/patología , Neoplasias de la Próstata/terapia , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteína p53 Supresora de Tumor/metabolismo
8.
Acta Cytol ; 49(2): 157-62, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15839620

RESUMEN

OBJECTIVE: To evaluate the usefulness of urine specimens collected via a mailer system and analyzed by cytology and DNA ploidy for the detection of urothelial carcinoma (UC). STUDY DESIGN: We retrospectively reviewed the diagnoses of 91 mailed urine specimens received from 72 patients, 67% of whom had a history of UC. The specimens were fixed in an equal volume of 50% ethanol solution before being mailed. The cytologic findings were interpreted in conjunction with DNA ploidy image analysis. We compared these initial diagnoses with those of follow-up examinations, including biopsies, cystoscopic findings and urinary cytology/DNA ploidy analyses. In addition, to examine the quality of the mailed samples, 3 cytopathologists performed a blinded assessment of cytologic slides of 20 mailed and 17 fresh urinary samples for bacterial overgrowth, urothelial degeneration, and presence of proteinaceous material and crystals. RESULTS: Follow-up was available for 68 of the 91 mailed specimens. The sensitivity for detecting UC using mailed urine specimens that were analyzed by both cytology and DNA ploidy was 61%, while specificity was 92%. The levels of bacterial overgrowth and urothelial degeneration in the mailed specimens were not significantly greater than in the fresh specimens (p>0.05). The levels of proteinaceous material and crystals were significantly higher in the mailed specimens (p<0.05). CONCLUSION: The results of combined cytology and DNA ploidy image analysis by using mailed urine samples were comparable to those of fresh urine specimens for the detection of UC reported in previous publications. The increase in crystals and proteinaceous material did not impede diagnostic interpretation. The mailing system is a reliable and convenient method of monitoring and triaging patients with UC or related symptoms.


Asunto(s)
Carcinoma/diagnóstico , Carcinoma/orina , ADN/análisis , Ploidias , Neoplasias de la Vejiga Urinaria/diagnóstico , Neoplasias de la Vejiga Urinaria/orina , Vejiga Urinaria/patología , Adulto , Anciano , Anciano de 80 o más Años , Carcinoma/genética , Biología Celular/normas , ADN/genética , Análisis Mutacional de ADN/métodos , Análisis Mutacional de ADN/normas , Femenino , Humanos , Citometría de Imagen/métodos , Citometría de Imagen/normas , Masculino , Persona de Mediana Edad , Servicios Postales , Valor Predictivo de las Pruebas , Estudios Retrospectivos , Fijación del Tejido/métodos , Fijación del Tejido/normas , Neoplasias de la Vejiga Urinaria/genética , Orina/citología , Urotelio/patología
9.
Gene ; 302(1-2): 31-41, 2003 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-12527194

RESUMEN

Melanoma development in the fish Xiphophorus is determined, at least in part, by overexpression and activation of the Xmrk-2 oncogene, which triggers a variety of signal transduction pathways resulting in altered cell cycle control. We have begun analysing transcription factors which may link Xmrk-2 with regulation of cell proliferation or apoptosis. Towards this end, we have cloned an FKHR (FoxO sub-family) homolog from Xiphophorus maculatus. The isolated clone is a 2.7 kb cDNA encoding a predicted protein of 664 amino acids. The gene, which we have named FoxO5, maps to Xiphophorus Linkage Group XV. The protein product can be categorized within a branch of the FOXO sub-class, which includes: Danio rerio zFKHR (foxo5), Homo sapiens FKHR-L1 (FoxO3a) and Mus musculus FKHR2 (Foxo3). Notably, the Forkhead DNA binding domain, three Akt consensus phosphorylation sites and a carboxy-terminal minimal activation domain are each highly conserved. A mutated FoxO5 protein with disrupted Akt phosphorylation sites inhibits proliferation, but the wild-type protein fails to do so, when exogenously expressed in Xiphophorus cells derived from a melanoma. The same mutated protein predominantly localizes to the nucleus, yet the wild-type protein seldom does. Further characterization of Xiphophorus FoxO5 will contribute to understanding the molecular basis of carcinogenesis in these species.


Asunto(s)
Ciprinodontiformes/genética , Factores de Transcripción/genética , Animales , Secuencia de Bases , Mapeo Cromosómico , Clonación Molecular , Citoplasma/metabolismo , ADN Complementario/química , ADN Complementario/genética , ADN Complementario/aislamiento & purificación , Femenino , Expresión Génica , Proteínas Fluorescentes Verdes , Proteínas Luminiscentes/genética , Proteínas Luminiscentes/metabolismo , Masculino , Datos de Secuencia Molecular , Filogenia , ARN Mensajero/genética , ARN Mensajero/metabolismo , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/metabolismo , Análisis de Secuencia de ADN , Homología de Secuencia de Aminoácido , Células Tumorales Cultivadas
10.
Leuk Res ; 27(8): 743-50, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12801533

RESUMEN

We have previously reported that children with B-precursor acute lymphoblastic leukemia (ALL) who remained in remission after successfully completing therapy had leukemia cells detectable by polymerase chain reaction (PCR) (N Engl J Med 1997;336(5):317-23). These patients were treated by an institutional protocol (P89-04) that lacked the post-remission intensification features of the contemporary Berlin-Frankfurt-Münster (BFM) based ALL protocols. In this report, we compared residual leukemia levels for patients on the P89-04 (n=15) and BFM-based Children's Cancer Group (CCG) studies (n=23) and for patients stratified according to risk group. Our goal was to establish which risk factors correlated with level of residual disease. Patients enrolled on the CCG protocols had lower levels of residual disease after completion of therapy than the P89-04 patients (P<0.019). Patients with high-risk disease also had lower levels of residual disease than patients with low risk disease (P<0.0001). Three-way analysis including time off treatment, risk group determined by features at presentation, and treatment protocol showed that risk group was the only significant independent variable (P<0.001).


Asunto(s)
Protocolos de Quimioterapia Combinada Antineoplásica/uso terapéutico , Neoplasia Residual , Leucemia-Linfoma Linfoblástico de Células Precursoras B/diagnóstico , Leucemia-Linfoma Linfoblástico de Células Precursoras/diagnóstico , Examen de la Médula Ósea , Genes de Inmunoglobulinas , Humanos , Neoplasia Residual/diagnóstico , Neoplasia Residual/tratamiento farmacológico , Neoplasia Residual/etiología , Reacción en Cadena de la Polimerasa , Leucemia-Linfoma Linfoblástico de Células Precursoras B/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Inducción de Remisión , Medición de Riesgo , Factores de Riesgo , Factores de Tiempo
11.
Environ Mol Mutagen ; 41(4): 300-8, 2003.
Artículo en Inglés | MEDLINE | ID: mdl-12717785

RESUMEN

Manufactured gas plant (MGP) residues, commonly known as coal tars, were generated several decades ago as a byproduct of residential and industrial gas production from the distillation of coal. Previous short-term exposure studies have shown MGP residues to be tumorigenic in mouse liver and lung. In order to gain further insight into carcinogenesis by complex mixtures of environmental chemicals containing known carcinogenic polycyclic aromatic hydrocarbons, we investigated mouse pulmonary tumors for loss of heterozygosity (LOH) as a result of multiple exposure to MGP residues. Twenty mouse lung adenomas produced in (C57BL/6 x C3H)F1 hybrid mice and manually microdissected were selected to examine genome-wide allelic losses at 58 microsatellite loci. Regions of chromosomes 1, 4, 5, 8, and 11 were affected in 30-40% of tumors. The elevated rates of allelic imbalance in these chromosomes may indicate the location of unknown tumor suppressor genes significant to neoplastic transformation in mouse lung tissues. Laser capture microdissection-based LOH analysis of pulmonary adenomas showed that contamination of nonneoplastic tissues was not masking the allelic losses in the manually microdissected tumor analysis. The low frequency of chromosome instability in these tumors, measured by means of inter-simple sequence repeat PCR, suggests the presence of discrete regions of LOH instead of extensive structural rearrangements.


Asunto(s)
Adenoma/genética , Alquitrán/toxicidad , Pérdida de Heterocigocidad , Neoplasias Pulmonares/genética , Adenoma/inducido químicamente , Animales , Femenino , Genotipo , Neoplasias Pulmonares/inducido químicamente , Ratones , Ratones Endogámicos C3H , Ratones Endogámicos C57BL , Reacción en Cadena de la Polimerasa
12.
Med Phys ; 29(9): 2052-61, 2002 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-12349926

RESUMEN

Amorphous silicon/cesium iodide (a-Si:H/CsI:Tl) flat-panel (FP)-based full-field digital mammography systems have recently become commercially available for clinical use. Some investigations on physical properties and imaging characteristics of these types of detectors have been conducted and reported. In this perception study, a phantom containing simulated microcalcifications (microCs) of various sizes was imaged with four detector systems: a FP system, a small field-of-view charge coupled device (CCD) system, a high resolution computed radiography (CR) system, and a conventional mammography screen/film (SF) system. The images were reviewed by mammographers as well as nonradiologist participants. Scores reflecting confidence ratings were given and recorded for each detection task. The results were used to determine the average confidence-rating scores for the four imaging systems. Receiver operating characteristics (ROC) analysis was also performed to evaluate and compare the overall detection accuracy for the four detector systems. For calcifications of 125-140 microm in size, the FP system was found to have the best performance with the highest confidence-rating scores and the greatest detection accuracy (Az = 0.9) in the ROC analysis. The SF system was ranked second while the CCD system outperformed the CR system. The p values obtained by applying a Student t-test to the results of the ROC analysis indicate that the differences between any two systems are statistically significant (p<0.005). Differences in microC detectability for the large (150-160 microm) and small (112-125 microm) size microC groups showed a wider range of p values (not all p values are smaller than 0.005, ranging from 0.6 to <0.001) compared to the p values obtained for the medium (125-140 microm) size microC group. Using the p values to assess the statistical significance, the use of the average confidence-rating scores was not as significant as the use of the ROC analysis p value for p value.


Asunto(s)
Neoplasias de la Mama/diagnóstico por imagen , Calcinosis/diagnóstico por imagen , Mamografía/instrumentación , Intensificación de Imagen Radiográfica/instrumentación , Presentación de Datos , Análisis de Falla de Equipo , Femenino , Humanos , Mamografía/métodos , Variaciones Dependientes del Observador , Fantasmas de Imagen , Curva ROC , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Grabación en Video/instrumentación
13.
Appl Immunohistochem Mol Morphol ; 11(1): 85-91, 2003 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-12610362

RESUMEN

We tested a recently developed flexible method of separation and quantification of immunohistochemical staining by means of color image analysis. An algorithm was recently developed to deconvolve the color information acquired with RGB cameras, to calculate the contribution of each of the applied stains, based on the stain-specific RGB absorption. The algorithm was tested using a set of lung-tumor samples labeled for the detection of Ki-67, an antigen expressed in proliferating cells, covering a wide range of staining levels. Quantification of the labeling was compared with HSI-based segmentation and manual analysis of the same samples. The recently developed deconvolution method performed significantly better than the HSI based system when compared to manual counting as gold standard. The deconvolution system showed significantly reduced variability in the LI determination, especially of highly labeled control samples. This resulted in significant increase in sensitivity of classification of samples with increased KI-67 labeling without changing the specificity, when compared to the HSI based method.


Asunto(s)
Coloración y Etiquetado/métodos , Algoritmos , Inmunohistoquímica
14.
Photochem Photobiol ; 79(5): 447-52, 2004 May.
Artículo en Inglés | MEDLINE | ID: mdl-15191054

RESUMEN

Selected hybridization in the fish genus Xiphophorus has been used for many years to study the genetics of malignant melanoma. Because DNA damage caused by ultraviolet radiation is implicated in the etiology of sunlight-induced melanoma, the heritability of mechanisms that mitigate DNA damage is a matter of some interest. We examined nucleotide excision repair of the two major types of DNA-damage induced by sunlight; the cyclobutane pyrimidine dimer (CPD) and the pyrimidine(6-4)pyrimidone dimer [(6-4)PD]. In most cases, removal of the (6-4)PD was more rapid than the CPD, and in many cases, the F1 hybrid showed reduced repair efficiency compared with the parental species. These data demonstrate reduced function in multienzyme hybrid systems and provide molecular support for potential reduced fitness in hybrid fish under conditions of environmental stress.


Asunto(s)
Ciprinodontiformes/genética , Daño del ADN , Reparación del ADN , ADN/efectos de la radiación , Dímeros de Pirimidina , Luz Solar , Animales , Reparación del ADN/genética , Fotobiología , Dímeros de Pirimidina/genética , Dímeros de Pirimidina/metabolismo , Dímeros de Pirimidina/efectos de la radiación , Especificidad de la Especie
15.
Anticancer Res ; 22(3): 1481-90, 2002.
Artículo en Inglés | MEDLINE | ID: mdl-12168827

RESUMEN

The CTL response to Ag expands after priming and subsequently contracts reducing the number of effectors. CD4+ cells are described as regulators of CTL immunity. To elucidate whether CD4+ cells are involved in survival of effector CTL and the survival signals, we used CTL and Th peptides form the HER-2 protooncogene recognized in association with HL-A2 and HLA-DR4, respectively. We analyzed the effect of cells stimulated with G89 (777-789) in survival and expression of lytic function of CTL specific for the epitope E75 (369-377). G89 primed cells (G89-PR) and G89 enhanced expansion and Ag-specific cytolyis of CTL at priming with E75, but inhibited survival of E75-specific CTL at restimulation. These effects were not simply a reflection of the increases in IFN-gamma and IL-10, but the ratio IFN-gamma/lL-10 modified by G89 differentially regulated the survival of stimulated cells. This suggests that the use of helper antigens in cancer vaccines should be evaluated in the context of their CTL survival inducing effect.


Asunto(s)
Epítopos de Linfocito T/inmunología , Interferón gamma/metabolismo , Interleucina-10/metabolismo , Receptor ErbB-2/inmunología , Linfocitos T Citotóxicos/inmunología , Linfocitos T Reguladores/inmunología , Antígenos CD40/biosíntesis , Antígenos CD40/genética , Antígenos CD40/inmunología , Supervivencia Celular/inmunología , Supervivencia Celular/fisiología , Células Dendríticas/inmunología , Antígeno HLA-A2/biosíntesis , Antígeno HLA-A2/genética , Antígeno HLA-A2/inmunología , Antígeno HLA-DR4/biosíntesis , Antígeno HLA-DR4/genética , Antígeno HLA-DR4/inmunología , Humanos , Interferón gamma/inmunología , Interleucina-10/inmunología , Activación de Linfocitos/inmunología , Fragmentos de Péptidos/inmunología , Linfocitos T Citotóxicos/citología , Linfocitos T Reguladores/citología , Regulación hacia Arriba
16.
Int J Oral Maxillofac Implants ; 28(2): 453-60, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23527347

RESUMEN

PURPOSE: The purpose of this study was to refine the Toronto Outcome Measure for Craniofacial Prosthetics (TOMCP), present evidence for its reliability and validity, and use the instrument to explore differences in quality of life between prostheses made with chlorinated polyethylene (CPE) (experimental) and silicone (control). MATERIALS AND METHODS: As part of a multicenter prospective controlled randomized double-blind single-crossover clinical trial of the two materials, the TOMCP was administered at the start and end of two 4-month study arms, during which 42 patients wore prostheses made from one material then the other. Reliability was assessed at the crossover. To determine validity of the TOMCP, the Linear Analogue Self-Assessment (LASA-12) and the Short-Form 8 (SF-8) were also administered with the TOMCP. The TOMCP was reduced by removing items that were unreliable, had poorly distributed answers, showed increased internal consistency after their removal, or were too highly correlated with more than one other item. The tests of reliability and validity were then repeated. Finally, the reduced instrument was used to test for differences in quality of life between prostheses made of the two materials. RESULTS: The item reduction tactics pared the 52-item instrument down to 27 items. The correlations of both TOMCP versions with the LASA-12 and the SF-8 were found to be statistically significant, providing evidence of the validity of the TOMCP. The instrument revealed significantly better quality of life with silicone rather than CPE prostheses. CONCLUSIONS: Both versions of the TOMCP were found to be reliable and valid. The instrument was able to show differences in quality of life between two materials.


Asunto(s)
Prótesis Maxilofacial/psicología , Evaluación de Resultado en la Atención de Salud , Polietilenos , Calidad de Vida , Siliconas , Encuestas y Cuestionarios , Adulto , Anciano , Imagen Corporal/psicología , Estudios Cruzados , Método Doble Ciego , Femenino , Humanos , Relaciones Interpersonales , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Prótesis e Implantes , Reproducibilidad de los Resultados , Resultado del Tratamiento
17.
Int J Prosthodont ; 23(3): 263-70, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20552094

RESUMEN

PURPOSE: Extraoral maxillofacial prostheses have been fabricated with silicone elastomer for 50 years with few improvements. The objective of this controlled, randomized, prospective, double-blind, single-crossover, multicenter, phase III clinical trial was to determine the noninferiority of chlorinated polyethylene elastomer (CPE) to silicone elastomer for fabricating prostheses. MATERIALS AND METHODS: Forty-two patients were randomly assigned to wear a custom-made prosthesis fabricated from both materials for 4 months and asked to rate their satisfaction (0 = not satisfied, 10 = completely satisfied). Many other measures of prosthesis performance were investigated (see online appendices). RESULTS: Of the 28 patients who completed the study, 68% had used silicone prostheses previously. Overall, patients rated the silicone prosthesis higher than CPE (difference: 2.2, 95% confidence interval [CI]: 0.9 to 3.6, P = .017). Previous users had a stronger preference for silicone (difference: 3.3, 95% CI: 1.7 to 4.9, P = .001), while the 9 new users rated the two materials similarly (difference: 0.0, 95% CI: -2.1 to 2.1, P = 1.00). CONCLUSIONS: The noninferiority of CPE could not be established because of the early termination of the trial. Previous users of silicone prostheses preferred those made of silicone. However, new users expressed no preference between prostheses fabricated with the low-cost CPE or silicone. The authors have developed original clinical trial methodology for assessing extraoral maxillofacial prostheses.


Asunto(s)
Elastómeros/química , Polietilenos/química , Prótesis e Implantes , Adulto , Actitud Frente a la Salud , Estudios Cruzados , Método Doble Ciego , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Satisfacción del Paciente , Poliuretanos/química , Estudios Prospectivos , Coloración de Prótesis , Diseño de Prótesis , Ajuste de Prótesis , Calidad de Vida , Elastómeros de Silicona/química , Análisis de Supervivencia , Resultado del Tratamiento
18.
Cancer Immunol Immunother ; 55(10): 1209-18, 2006 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-16331519

RESUMEN

Between March 1999 and May 2000, 18 HLA-A*0201(+) patients with metastatic melanoma were enrolled in a phase I trial using a dendritic cell (DC) vaccine generated by culturing CD34(+) hematopoietic progenitors. This vaccine includes Langerhans cells. The DC vaccine was loaded with four melanoma peptides (MART-1/MelanA, tyrosinase, MAGE-3, and gp100), Influenza matrix peptide (Flu-MP), and keyhole limpet hemocyanin (KLH). Ten patients received eight vaccinations, one patient received six vaccinations, one patient received five vaccinations, and six patients received four vaccinations. Peptide-specific immunity was measured by IFN-gamma production and tetramer staining in blood mononuclear cells. The estimated median overall survival was 20 months (range: 2-83), and the median event-free survival was 7 months (range: 2-83). As of August 2005, four patients are alive (three patients had M1a disease and one patient had M1c disease). Three of them have had no additional therapy since trial completion; two of them had solitary lymph node metastasis, and one patient had liver metastasis. Patients who survived longer were those who mounted melanoma peptide-specific immunity to at least two melanoma peptides. The present results therefore justify the design of larger follow-up studies to assess the immunological and clinical outcomes in patients with metastatic melanoma vaccinated with peptide-pulsed CD34-derived DCs.


Asunto(s)
Vacunas contra el Cáncer/uso terapéutico , Células Dendríticas/inmunología , Melanoma/terapia , Proteínas de Neoplasias/inmunología , Células Madre/inmunología , Adulto , Anciano , Antígenos CD34/inmunología , Antígenos de Neoplasias/inmunología , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/inmunología , Citometría de Flujo , Humanos , Interferón gamma/biosíntesis , Interferón gamma/inmunología , Activación de Linfocitos , Antígeno MART-1 , Melanoma/inmunología , Melanoma/mortalidad , Glicoproteínas de Membrana/inmunología , Persona de Mediana Edad , Monofenol Monooxigenasa/inmunología , Análisis de Supervivencia , Tiempo , Resultado del Tratamiento , Antígeno gp100 del Melanoma
19.
J Immunother ; 29(5): 545-57, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16971810

RESUMEN

Dendritic cells (DCs) loaded with killed allogeneic tumors can cross-prime tumor-specific naive CD8 T cells in vitro, thereby providing an option to overcome human leukocyte antigen restriction inherent to loading DC vaccines with peptides. We have vaccinated 20 patients with stage IV melanoma with autologous monocyte-derived DCs loaded with killed allogeneic Colo829 melanoma cell line. DCs were generated by culturing monocytes with granulocyte macrophage-colony stimulating factor (granulocyte macrophage-colony stimulating factor) and interleukin (IL-4) and activated by additional culture with tumor necrosis factor and CD40 ligand. A total of 8 vaccines were administered at monthly intervals. The first patient was accrued December 2002 and the last November 2003. Fourteen patients were alive at 12 months, 9 patients were alive at 24 months, and 8 patients are alive as of January 2006. The estimated median overall survival is 22.5 months with a range of 2 to 35.5 months. Vaccinations were safe and tolerable. They induced, in 2 patients who failed previous therapy, durable objective clinical responses, 1 complete regression (CR) and 1 partial regression (PR) lasting 18 and 23 months, respectively. Three out of 13 analyzed patients showed T-cell immunity to melanoma antigen recognized by autologous T cells (MART-1) tissue differentiation antigen. Two of 3 patients showed improved immune function after vaccinations demonstrated by improved secretion of interferon (IFN)-gamma or T-cell proliferation in response to MART-1 derived peptides. In one of these patients, vaccination led to elicitation of CD8 T-cell immunity specific to a novel peptide-derived from MART-1 antigen, suggesting that cross-priming/presentation of melanoma antigens by DC vaccine had occurred. Thus, the present results justify the design of larger follow-up studies to assess the clinical response to DC vaccines loaded with killed allogeneic tumor cells in patients with metastatic melanoma.


Asunto(s)
Antígenos de Neoplasias/inmunología , Linfocitos T CD8-positivos/inmunología , Vacunas contra el Cáncer/uso terapéutico , Células Dendríticas/inmunología , Melanoma/terapia , Proteínas de Neoplasias/inmunología , Neoplasias Cutáneas/terapia , Adulto , Anciano , Vacunas contra el Cáncer/efectos adversos , Diferenciación Celular , Línea Celular Tumoral , Reactividad Cruzada , Citotoxicidad Inmunológica , Células Dendríticas/citología , Antígeno HLA-A2/inmunología , Humanos , Inmunoterapia Adoptiva , Interferón gamma/metabolismo , Antígeno MART-1 , Melanoma/inmunología , Melanoma/patología , Persona de Mediana Edad , Monocitos/citología , Monocitos/inmunología , Metástasis de la Neoplasia , Péptidos/inmunología , Neoplasias Cutáneas/inmunología , Neoplasias Cutáneas/patología , Tasa de Supervivencia , Trasplante Homólogo
20.
Cancer ; 107(1): 75-82, 2006 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-16736511

RESUMEN

BACKGROUND: Although prostate cancer (PC) mortality disproportionately affects African-American (AA) men, limited data exist comparing the pathologic characteristics of white and AA patients with nonpalpable PC (clinical stage T1c). METHODS: The authors reviewed the radical prostatectomy (RP) specimens from 37 consecutive AA men with clinical stage T1c PC and 35 white men who were matched for age, clinical stage, serum prostate-specific antigen (PSA) level, year of surgery, prostate weight, and prostate biopsy strategy. Pathologic characteristics were compared after mapping tumor foci and calculating tumor volumes by using computer software. RESULTS: For AA men, the median age (57.7 years), mean serum PSA level (9.3 ng/mL), mean prostate weight (43 g), and biopsy strategy (73% sextant) were matched with the cohort of 35 white men (median age, 57.1 years; mean PSA, 9.3 ng/mL;, mean prostate weight, 43 g; biopsy strategy, 66% sextant). Despite similar biopsy characteristics between the 2 groups (Gleason score > or =7 in 43% of AA men vs. 37% of white men), AA men exhibited significantly higher prostatectomy Gleason scores (> or =7 in 76% of AA men vs. 34% of white men; P = .01). AA men also had a higher mean tumor volume (1.82 cm3 vs. 0.72 cm3; P = .001) and had 2.8 times more tumor per ng/mL of serum PSA (0.22 cm3 per ng/mL vs. 0.079 cm3 per ng/mL; P = .001). CONCLUSIONS: Compared with a cohort of white men with similar clinical features at the time of biopsy, AA men with nonpalpable PC had higher prostatectomy Gleason scores, greater cancer volume, and greater tumor volume per ng/mL of serum PSA. These data provide additional support for the concept of early PC detection using a serum PSA threshold of 2.5 ng/mL for biopsy among AA men.


Asunto(s)
Población Negra , Antígeno Prostático Específico/análisis , Neoplasias de la Próstata/patología , Población Blanca , Negro o Afroamericano , Estudios de Cohortes , Humanos , Masculino , Persona de Mediana Edad , Estadificación de Neoplasias , Tamaño de los Órganos , Prostatectomía , Neoplasias de la Próstata/diagnóstico
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