Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 100
Filtrar
1.
Mutagenesis ; 2024 Apr 12.
Artículo en Inglés | MEDLINE | ID: mdl-38606763

RESUMEN

Pleiotropic variants (i.e., genetic polymorphisms influencing more than one phenotype) are often associated with cancer risk. A scan of pleiotropic variants was successfully conducted ten years ago in relation to pancreatic ductal adenocarcinoma susceptibility. However, in the last decade, genetic association studies performed on several human traits have greatly increased the number of known pleiotropic variants. Based on the hypothesis that variants already associated with a least one trait have a higher probability of association with other traits, 61,052 variants reported to be associated by at least one genome wide association study (GWAS) with at least one human trait were tested in the present study consisting of two phases (discovery and validation), comprising a total of 16,055 pancreatic ductal adenocarcinoma (PDAC) cases and 212,149 controls. The meta-analysis of the two phases showed two loci (10q21.1-rs4948550 (P=6.52×10-5) and 7q36.3-rs288762 (P=3.03×10-5) potentially associated with PDAC risk. 10q21.1-rs4948550 shows a high degree of pleiotropy and it is also associated with colorectal cancer risk while 7q36.3-rs288762 is situated 28,558 base pairs upstream of the Sonic Hedgehog (SHH) gene, which is involved in the cell differentiation process and PDAC etiopathogenesis. In conclusion, none of the single nucleotide polymorphisms (SNPs) showed a formally statistically significant association after correction for multiple testing. However, given their pleiotropic nature and association with various human traits including colorectal cancer, the two SNPs showing the best associations with PDAC risk merit further investigation through fine mapping and ad hoc functional studies.

2.
Eur Rev Med Pharmacol Sci ; 26(19): 7277-7284, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36263539

RESUMEN

OBJECTIVE: Telemedicine (TM) has had a powerful impact in recent years, particularly on managing chronic diseases such as inflammatory bowel disease (IBD). Knowing patients' expectations and concerns is essential to increase their confidence in this mode of medical care. PATIENTS AND METHODS: We interviewed a large cohort of IBD patients enrolled at two Italian tertiary referral centers to investigate their trust in TM. RESULTS: A total of 376 patients completed the survey and were included in the study: 293 (77.9%) considered TM valuable for managing their disease, and 307 (85%) wanted to have TM service at their center. However, only 99 patients (26.3%) believed that TM guarantees the same level of care as the in-person visit. Among the socio-demographic variables, those independently associated with trust in TM were the higher education qualification (p=0.02) and the level of competence in information and communication technologies (ICT) (p=0.03). CONCLUSIONS: Our findings highlighted the importance of equipping IBD patients with basic ICT skills to utilize TM services and increase their confidence in ICT with the help of caregivers. Additionally, to improve the perceived value of TM, it will be helpful to use additional tools such as telemonitoring of disease activity using patients' reported outcomes or remote measurement of fecal calprotectin.


Asunto(s)
COVID-19 , Enfermedades Inflamatorias del Intestino , Telemedicina , Humanos , Pandemias , Estudios Transversales , Confianza , Enfermedades Inflamatorias del Intestino/diagnóstico , Enfermedades Inflamatorias del Intestino/terapia , Enfermedades Inflamatorias del Intestino/epidemiología , Enfermedad Crónica , Complejo de Antígeno L1 de Leucocito
3.
Eur Rev Med Pharmacol Sci ; 26(4): 1350-1363, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35253191

RESUMEN

OBJECTIVE: The aim of this study was to identify features mainly involved in determining the partial response (PR) to the Electrochemotherapy (ECT) in patients with recurrent and/or metastatic head and neck (H&N) tumor; the identified features were also used in a decision chart in order to provide the clinician with a support tool in deciding further therapies. PATIENTS AND METHODS: 131 patients (186 treatment sessions) with recurrent and/or metastatic H&N neoplasm were subjected to ECT. Treatment response was evaluated based on Response Evaluation Criteria in Solid Tumors (RECIST) v. 1.1 two months after the ECT. The grade of bleeding and pain before, at the end and one week after ECT treatment were evaluated. Univariate and multivariate analysis were performed to identify features involved in determining the patient PR. RESULTS: In the context of the univariate analysis, tumor size significantly influenced the response to ECT, with higher PR rate of 58.3%: 28 among 48 patients with lesion size ≤ 3 centimeters (p-value < 0.001 at Chi-square test). Pain and bleeding pre-treatment were positively correlated to PR (p-value < 0.001 at Chi-square test). A difference in the current flowing in the tissue during treatment was also observed in partially responsive patients, where the median current value (6.6 A) was higher than that achieved in patients that did not show PR (3.3 A). In the context of the multivariate analysis, the best performances are achieved with the BART method (accuracy of 84%). The main clinical factors to predict the partial response, among investigated features, that have shown to be considered were the pain value felt before performing the treatment and the median current delivered during the ECT treatment. A decision-making support tool to predict the patient prognosis in terms of response rate could be represented by the decision tree obtained with CART algorithm, where a pain pre-treatment more than 5 and a median delivered current not less than 2.8 A led to the prediction a partial responsive patient with an accuracy of 75%. CONCLUSIONS: The study confirmed that ECT is an interesting antitumoral therapy in advanced chemo- and radio-refractory H&N neoplasms, able to reduce frequent symptoms and to improve the quality of life. Pain pre-treatment and delivered current are the most important variables when predicting the partial response of patients.


Asunto(s)
Electroquimioterapia , Neoplasias de Cabeza y Cuello , Neoplasias Cutáneas , Bleomicina/efectos adversos , Electroquimioterapia/efectos adversos , Neoplasias de Cabeza y Cuello/tratamiento farmacológico , Humanos , Dolor/tratamiento farmacológico , Cuidados Paliativos/métodos , Calidad de Vida , Neoplasias Cutáneas/tratamiento farmacológico , Resultado del Tratamiento
4.
Eur Rev Med Pharmacol Sci ; 25(6): 2744-2747, 2021 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-33829460

RESUMEN

OBJECTIVE: From September 2020, a second wave of COVID-19 pandemic started. We aimed at exploring the impact of SARS-CoV-2 infection in IBD patients during the two waves. PATIENTS AND METHODS: All IBD patients with a confirmed diagnosis of SARS-CoV-2 infection were enrolled. They were sorted into two groups (those infected before September 2020, and those from September 2020 to January 2021) and compared by demographic and clinical data. RESULTS: Twenty-five patients (out of about 600 with a follow-up visit) were infected with SARS-CoV-2 (4.1%). Sixteen were male and the mean age was 46.5 ± 14.3 years (range 24-74). Six were smokers and 11 had comorbidities; 2 were on steroids and 17 on immunosuppressants or biologics. Three patients (12%) needed hospitalization and other three patients were treated with azithromycin, steroids and LMWH, all of them during the second wave. No patient died or developed any sequelae. Two subjects were infected during the first wave (0.3 vs. 3.83, p<0.0001). Non-significant differences were found between the two groups. CONCLUSIONS: A higher number of IBD patients were infected during the second wave. No patient developed a severe form of pneumonia, even those treated with immunosuppressants or biologics. No risk factor for hospitalization was found.


Asunto(s)
COVID-19/epidemiología , Enfermedades Inflamatorias del Intestino/epidemiología , Adulto , Anciano , COVID-19/transmisión , COVID-19/virología , Femenino , Estudios de Seguimiento , Hospitalización/estadística & datos numéricos , Humanos , Enfermedades Inflamatorias del Intestino/virología , Italia/epidemiología , Masculino , Persona de Mediana Edad , SARS-CoV-2/aislamiento & purificación , Adulto Joven
5.
World J Urol ; 38(1): 143-150, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30993426

RESUMEN

BACKGROUND: Basophils, eosinophils and monocytes may be involved in BCG-induced immune responses and be associated with outcomes of bladder cancer patients receiving intravesical BCG. Our objective was to explore the association of baseline counts of basophils, eosinophils and monocytes with outcomes of patients with high-grade T1 bladder cancer receiving a standard course of intravesical BCG. METHODS: We retrospectively reviewed medical records of patients with primary T1 HG/G3 bladder cancer. After re-TURBT, patients were treated with a 6-week course of intravesical BCG induction followed by intravesical BCG every week for 3 weeks given at 3, 6, 12, 18, 24, 30 and 36 months from initiation of therapy The analysis of potential risk factors for recurrence, muscle invasion and cancer-specific and overall survival was performed using univariable Cox regression models. Those factors that presented, at univariate analysis, an association with the event at a liberal p < 0.1, have been selected for the development of a multivariable model. RESULTS: A total of 1045 patients with primary T1 HG/G3 were included. A total of 678 (64.9%) recurrences, 303 (29.0%) progressions and 150 (14.3%) deaths were observed during follow-up. Multivariate analysis showed that logarithmic transformation of basophils count was associated with a 30% increment in the hazard of recurrence per unit increase of logarithmic basophils count (HR 1.30; 95% confidence interval 1.09-1.54; p = 0.0026). Basophil count modeled by quartiles was also significantly associated with time to recurrence [second vs. lower quartile HR 1.42 (1.12-1.79); p = 0.003, third vs. lower quartile HR 1.26 (1.01-1.57); p = 0.041; upper vs. lower quartile HR 1.36 (1.1-1.68); p = 0.005]. The limitations of a retrospective study are applicable. CONCLUSION: Baseline basophil count may predict recurrence in BCG-treated HG/G3 T1 bladder cancer patients. External validation is warranted.


Asunto(s)
Vacuna BCG/administración & dosificación , Basófilos/patología , Cistectomía/métodos , Recurrencia Local de Neoplasia/diagnóstico , Estadificación de Neoplasias/métodos , Neutrófilos/patología , Neoplasias de la Vejiga Urinaria/terapia , Adyuvantes Inmunológicos/administración & dosificación , Administración Intravesical , Adulto , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Estudios de Seguimiento , Humanos , Recuento de Leucocitos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Factores de Tiempo , Neoplasias de la Vejiga Urinaria/patología
6.
Onco Targets Ther ; 12: 1583-1591, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30881013

RESUMEN

Nasopharyngeal carcinoma is a rare disease in Western countries. Nevertheless, its incidence in China, Singapore, and other Eastern countries reaches 20 cases per 100,000 people. Being an extremely chemo- and radiosensitive disease, upfront treatment often consists in the association of intensity-modulated radiation therapy and concurrent cisplatin. Unfortunately, about 20% of the patients suffer from a radioresistant disease which recurs after upfront therapy. For these patients, mainly available therapeutic options consist in systemic therapy, in particular poly-chemotherapy. In those showing a single locoregional recurrence, chemotherapy is not considered to be the preferred approach and other different strategies may be employed. Re-irradiation and surgery are strategies that are always used more often, albeit related to high risk of morbidity. Immunotherapy and targeted therapy, such as heavy ions-based re-irradiations, are experimental but very intriguing options.

7.
Anticancer Agents Med Chem ; 18(9): 1220-1227, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29637868

RESUMEN

BACKGROUND: Squamous Cell Carcinoma of the Head and Neck (SCCHN) are neoplasms arising from the epithelium of the first aero-digestive tract. They are very heterogeneous both clinically and biologically. Classic and well acknowledged risk factors are alcohol and tobacco consumption and other forms of smokeless tobacco assumption, although lately the incidence of Human Papilloma Virus (HPV)-related SCCHN is rapidly increasing. HPV-related tumors are very different from their alcohol and tobacco-associated counterpart, as they show strong chemo and radio sensitivity and thus can often be treated with conservative treatment strategies. Moreover, peculiar biologic features characterize HPV-related tumors, such as wild type TP53, low expression of Epidermal Growth Factor Receptor (EGFR), wild type CCND1 and high expression of P16. In contrast, alcohol and tobacco related SCCHN show opposite features, together with higher number of chromosomal and genetic abnormalities, conferring them chemo and radio resistance. METHODS: We have performed a narrative review of the PubMed database with the aim to study the mutational landscape of SCCHN. RESULTS: Several lines of evidence support the existence of at least two genetically different types of SCCHN, one virus-related and the other alcohol and/or tobacco-related, characterized by both clinical and biological opposite features. Virus related SCCHN are very chemo and radiosensitive, so suitable for organ preserving strategy, which in the near future may be induction chemotherapy followed by association of chemotherapy and underpowered radiotherapy. Alcohol and tobacco related SCCHN are themselves strongly heterogeneous and can be divided in different entities on the basis of the "Driver" genetic aberration, responsible for carcinogenesis. The most frequently mutated genes in alcohol and tobacco-related SCCHN are TP53, NOTCH1, CCND1, CDKN2A, EGFR and PI3KCA. CONCLUSIONS: Virus-related SCCHN can be managed with chemo-radiotherapy. Alcohol and tobacco-related tumors should be further characterized on the basis of their "Driver Mutations" in order to select effective targeted therapies.


Asunto(s)
Neoplasias de Cabeza y Cuello/etiología , Neoplasias de Cabeza y Cuello/terapia , Carcinoma de Células Escamosas de Cabeza y Cuello/etiología , Carcinoma de Células Escamosas de Cabeza y Cuello/terapia , Consumo de Bebidas Alcohólicas/efectos adversos , Animales , Manejo de la Enfermedad , Neoplasias de Cabeza y Cuello/genética , Neoplasias de Cabeza y Cuello/virología , Humanos , Mutación , Papillomaviridae/aislamiento & purificación , Carcinoma de Células Escamosas de Cabeza y Cuello/genética , Carcinoma de Células Escamosas de Cabeza y Cuello/virología , Fumar Tabaco/efectos adversos , Investigación Biomédica Traslacional
8.
Crit Rev Oncol Hematol ; 111: 166-172, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28259291

RESUMEN

Epigenetic changes are defined as inherited modifications that are not present in DNA sequence. Gene expression is regulated at various levels and not only in response to DNA modifications. Examples of epigenetic control are DNA methylation, histone deacetylation and mi-RNA expression. Methylation of several tumor suppressor gene promoters is responsible for their silencing and thus potentially sustain cancerogenesis. Similarly, histone deacetylation can lead to oncogene activation. mi-RNA are small (18-20 nucleotides) non-coding RNA fragments capable of inhibiting other m-RNA, ultimately altering the balance in oncogene and tumor suppressor gene expression. It has been shown that growth of several tumor types can be stimulated by epigenetic changes in various phases of cancerogenesis, and drugs able to interfere with these mechanisms can have a positive impact on tumor progression. As matter of fact, epigenetic changes are dynamic and can be reversed by epigenetic inhibitors. Recently, methyltransferase and histone deacetylase inhibitors have attracted the attention of researchers and clinicians as they potentially provide alternative therapeutic options in some cancers. Drugs that inhibit DNA methylation or histone deacetylation have been studied for the reactivation of tumor suppressor genes and repression of cancer cell growth. Epigenetic inhibitors work alone or in combination with other therapeutic agents. To date, a number of epigenetic inhibitors have been approved for cancer treatment. The main challenge in the field of epigenetic inhibitors is their lack of specificity. In this review article we describe their mechanisms of action and potential in cancer treatment.


Asunto(s)
Neoplasias/tratamiento farmacológico , Neoplasias/genética , Carcinogénesis/genética , Metilación de ADN , Epigénesis Genética , Expresión Génica , Inhibidores de Histona Desacetilasas/uso terapéutico , Humanos , Regiones Promotoras Genéticas
10.
Bone Marrow Transplant ; 46(6): 840-6, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-20818442

RESUMEN

Autologous hematopoietic SCT (auto-SCT) has been effective therapy for refractory disease, in both malignancies and severe autoimmune diseases. It seems feasible and safe for refractory celiac disease (RCD) type II, although long-term results have not been evaluated yet. With current therapies, progression into enteropathy-associated T-cell lymphoma (EATL) occurs in 60-80% patients, with a high mortality rate. Therefore, it is important to evaluate new treatment strategies. Between March 2004 and February 2010, 18 RCD II patients were evaluated for auto-SCT preceded by conditioning with fludarabine and melphalan, as a consequence of unresponsiveness to cladribine therapy. Adverse events, survival rate, EATL development and change in clinical, histological and immunological course were monitored. Thirteen patients were transplanted successfully and followed up for >2 years, 4-year survival rate was 66%. Only one patient died because of transplant-related complications. The majority of patients showed an impressive clinical improvement and five a complete histological remission. In five patients, auto-SCT could not be performed; they all died with a median survival of 5.5 months. EATL was observed in one transplanted patient, only after 4 years of follow-up. Auto-SCT after conditioning with high-dose chemotherapy in RCD II patients unresponsive to cladribine therapy is feasible and seems promising.


Asunto(s)
Enfermedad Celíaca/terapia , Cladribina/uso terapéutico , Trasplante de Células Madre Hematopoyéticas/métodos , Terapia Recuperativa/métodos , Adulto , Anciano , Antineoplásicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Acondicionamiento Pretrasplante , Trasplante Autólogo , Resultado del Tratamiento
13.
Cancer Chemother Pharmacol ; 66(2): 209-18, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20333385

RESUMEN

The standard treatment of CRC patients with hepatic metastases is systemic chemotherapy; however, 5-year survival is disappointingly poor despite recent advances. On the other hand, in patients who undergo immediate radical surgical resection of hepatic metastases, 5-year survival reaches 30-40%. Unfortunately, only 15-20% of patients with hepatic metastases are initially eligible for a radical surgical approach. The majority of patients undergoing liver resection relapse after surgery. For this reason, new onco-surgery approaches have been investigated in recent years and the addition of biological agents to chemotherapy, such as bevacizumab and cetuximab, and the improvements of surgical techniques have opened a new scenario in the management of colorectal liver metastases. Recently, the EORTC trial has demonstrated that perioperative chemotherapy (Folfox regimen) is feasible and improves progression-free survival in patients with resectable liver metastases. Chemotherapy and surgery can finally collaborate. In the unresectable setting, the association of chemotherapy with bevacizumab and cetuximab is particularly promising in improving resectability rate. In particular, K-RAS is a molecular response predictive factor that could be particularly useful in selecting the best treatment option in patients with unresectable liver disease.


Asunto(s)
Antineoplásicos/uso terapéutico , Neoplasias Colorrectales/patología , Neoplasias Hepáticas/tratamiento farmacológico , Neoplasias Hepáticas/secundario , Quimioterapia Adyuvante , Ensayos Clínicos como Asunto , Terapia Combinada , Humanos , Neoplasias Hepáticas/cirugía , Cuidados Preoperatorios , Estudios Prospectivos , Estudios Retrospectivos
14.
Aliment Pharmacol Ther ; 29 Suppl 1: 1-49, 2009 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-19344474

RESUMEN

BACKGROUND: Breath tests represent a valid and non-invasive diagnostic tool in many gastroenterological conditions. The rationale of hydrogen-breath tests is based on the concept that part of the gas produced by colonic bacterial fermentation diffuses into the blood and is excreted by breath, where it can be quantified easily. There are many differences in the methodology, and the tests are increasingly popular. AIM: The Rome Consensus Conference was convened to offer recommendations for clinical practice about the indications and methods of H2-breath testing in gastrointestinal diseases. METHODS: Experts were selected on the basis of a proven knowledge/expertise in H2-breath testing and divided into Working Groups (methodology; sugar malabsorption; small intestine bacterial overgrowth; oro-coecal transit time and other gas-related syndromes). They performed a systematic review of the literature, and then formulated statements on the basis of the scientific evidence, which were debated and voted by a multidisciplinary Jury. Recommendations were then modified on the basis of the decisions of the Jury by the members of the Expert Group. RESULTS AND CONCLUSIONS: The final statements, graded according to the level of evidence and strength of recommendation, are presented in this document; they identify the indications for the use of H2-breath testing in the clinical practice and methods to be used for performing the tests.


Asunto(s)
Enfermedades Gastrointestinales/diagnóstico , Hidrógeno/análisis , Adulto , Infecciones Bacterianas/diagnóstico , Pruebas Respiratorias/métodos , Catárticos/uso terapéutico , Niño , Dieta , Carbohidratos de la Dieta/farmacocinética , Medicina Basada en la Evidencia , Ejercicio Físico/fisiología , Gases/análisis , Gases/metabolismo , Tránsito Gastrointestinal , Humanos , Hidrógeno/metabolismo , Hiperventilación/complicaciones , Metano/análisis , Metano/biosíntesis , Antisépticos Bucales/efectos adversos , Fumar/efectos adversos , Manejo de Especímenes
15.
Onco Targets Ther ; 2: 171-8, 2009 Feb 18.
Artículo en Inglés | MEDLINE | ID: mdl-20616904

RESUMEN

The ubiquitin-proteasome system has become a promising molecular target in cancer therapy due to its critical role in cellular protein degradation, interaction with cell cycle and apoptosis regulation, and unique mechanism of action. Bortezomib (PS-341) is a potent and specific reversible proteasome inhibitor, which has shown strong in vitro antitumor activity as single agent and in combination with other cytotoxic drugs in a broad spectrum of hematological and solid malignancies. In preclinical studies, bortezomib induced apoptosis of malignant cells through the inhibition of NF-|B and stabilization of pro-apoptotic proteins. Bortezomib also promotes chemo- and radiosensitization of malignant cells in vitro and inhibits tumor growth in murine xenograft models. The proteasome has been established as a relevant target in hematologic malignancies and bortezomib has been approved for the treatment of multiple myeloma. This review summarizes recent data from clinical trials in solid tumors.

16.
Protein J ; 27(1): 13-20, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17786545

RESUMEN

Three proteins belonging to the thaumatin-like proteins family were compared in this study from a structural point of view: zeamatin, a new recently isolated PR-5 from Cassia didymobotrya and the commercial sweet-thaumatin. The former two proteins possess antifungal activities while commercial thaumatin is well known to be a natural sweetener. Intrinsic fluorescence studies have evidenced that the three proteins behave differently in unfolding experiments showing different structural rigidity. All the three proteins are more stable at slight acidic buffers, but sweet-thaumatin has a major tendency to destructurate itself. Similar observations were made from circular dichroism studies where a structural dependence relationship from the pH and the solvent used confirmed a hierarchic scale of stability for the three proteins. These structural differences should be considered to be significant for a functional role.


Asunto(s)
Antifúngicos/química , Cassia/química , Proteínas de Plantas/química , Dicroismo Circular , Pliegue de Proteína , Espectrometría de Fluorescencia , Espectroscopía Infrarroja por Transformada de Fourier
17.
Bioinformatics ; 23(16): 2063-72, 2007 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-17540679

RESUMEN

MOTIVATION: A major challenge in current biomedical research is the identification of cellular processes deregulated in a given pathology through the analysis of gene expression profiles. To this end, predefined lists of genes, coding specific functions, are compared with a list of genes ordered according to their values of differential expression measured by suitable univariate statistics. RESULTS: We propose a statistically well-founded method for measuring the relevance of predefined lists of genes and for assessing their statistical significance starting from their raw expression levels as recorded on the microarray. We use prediction accuracy as a measure of relevance of the list. The rationale is that a functional category, coded through a list of genes, is perturbed in a given pathology if it is possible to correctly predict the occurrence of the disease in new subjects on the basis of the expression levels of the genes belonging to the list only. The accuracy is estimated with multiple random validation strategy and its statistical significance is assessed against a couple of null hypothesis, by using two independent permutation tests. The utility of the proposed methodology is illustrated by analyzing the relevance of Gene Ontology terms belonging to biological process category in colon and prostate cancer, by using three different microarray data sets and by comparing it with current approaches. AVAILABILITY: Source code for the algorithms is available from author upon request. SUPPLEMENTARY INFORMATION: Colon cancer data set and a complete description of experimental results are available at: ftp://bioftp:76bioftpxxx@marx.ba.issia.cnr.it/supp-info.htm.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica , Familia de Multigenes , Proteínas de Neoplasias/metabolismo , Neoplasias/metabolismo , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Interpretación Estadística de Datos , Humanos , Masculino , Proteínas de Neoplasias/clasificación
18.
BMC Bioinformatics ; 7: 387, 2006 Aug 19.
Artículo en Inglés | MEDLINE | ID: mdl-16919171

RESUMEN

BACKGROUND: In this paper we present a method for the statistical assessment of cancer predictors which make use of gene expression profiles. The methodology is applied to a new data set of microarray gene expression data collected in Casa Sollievo della Sofferenza Hospital, Foggia--Italy. The data set is made up of normal (22) and tumor (25) specimens extracted from 25 patients affected by colon cancer. We propose to give answers to some questions which are relevant for the automatic diagnosis of cancer such as: Is the size of the available data set sufficient to build accurate classifiers? What is the statistical significance of the associated error rates? In what ways can accuracy be considered dependant on the adopted classification scheme? How many genes are correlated with the pathology and how many are sufficient for an accurate colon cancer classification? The method we propose answers these questions whilst avoiding the potential pitfalls hidden in the analysis and interpretation of microarray data. RESULTS: We estimate the generalization error, evaluated through the Leave-K-Out Cross Validation error, for three different classification schemes by varying the number of training examples and the number of the genes used. The statistical significance of the error rate is measured by using a permutation test. We provide a statistical analysis in terms of the frequencies of the genes involved in the classification. Using the whole set of genes, we found that the Weighted Voting Algorithm (WVA) classifier learns the distinction between normal and tumor specimens with 25 training examples, providing e = 21% (p = 0.045) as an error rate. This remains constant even when the number of examples increases. Moreover, Regularized Least Squares (RLS) and Support Vector Machines (SVM) classifiers can learn with only 15 training examples, with an error rate of e = 19% (p = 0.035) and e = 18% (p = 0.037) respectively. Moreover, the error rate decreases as the training set size increases, reaching its best performances with 35 training examples. In this case, RLS and SVM have error rates of e = 14% (p = 0.027) and e = 11% (p = 0.019). Concerning the number of genes, we found about 6000 genes (p < 0.05) correlated with the pathology, resulting from the signal-to-noise statistic. Moreover the performances of RLS and SVM classifiers do not change when 74% of genes is used. They progressively reduce up to e = 16% (p < 0.05) when only 2 genes are employed. The biological relevance of a set of genes determined by our statistical analysis and the major roles they play in colorectal tumorigenesis is discussed. CONCLUSIONS: The method proposed provides statistically significant answers to precise questions relevant for the diagnosis and prognosis of cancer. We found that, with as few as 15 examples, it is possible to train statistically significant classifiers for colon cancer diagnosis. As for the definition of the number of genes sufficient for a reliable classification of colon cancer, our results suggest that it depends on the accuracy required.


Asunto(s)
Algoritmos , Análisis de Secuencia por Matrices de Oligonucleótidos/métodos , Estadística como Asunto/métodos , Anciano , Neoplasias del Colon/clasificación , Neoplasias del Colon/genética , Interpretación Estadística de Datos , Femenino , Perfilación de la Expresión Génica/métodos , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Masculino , Persona de Mediana Edad , Modelos Estadísticos , Análisis Numérico Asistido por Computador , Reproducibilidad de los Resultados , Programas Informáticos
19.
Aliment Pharmacol Ther ; 23(9): 1329-35, 2006 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-16629938

RESUMEN

BACKGROUND: Once small (<10 mm) nodules, suspicious for hepatocellular carcinoma, are detected in cirrhotics, the European Association for the Study of the Liver guidelines recommend to delay histological confirmation and treatment until they increase in size. AIM: To validate this policy by evaluating survival of 450 cirrhotics in Child-Pugh class A or B with unifocal 'early' hepatocellular carcinoma treated by percutaneous alcohol injection. METHODS: Patients were sorted by nodular size into three groups: < or =10 mm (n = 36, group A), >10 to < or = 20 mm (n = 142, group B) and >20 to < or = 30 mm (n = 272, group C). Overall and tumour-free survivals were estimated by Kaplan-Meier method. RESULTS: In groups A, B and C, mean follow-up was 33 +/- 26, 34 +/- 22 and 35 +/- 25 months (P = 0.89), mean survival time was 63 +/- 54, 57 +/- 48 and 62 +/- 66 months (P = 0.69) and mean tumour-free survival was 44 +/- 47, 46 +/- 58 and 41 +/- 68 months (P = 0.51), respectively. When patients were sorted by Child status, mean survival time was 76 +/- 82 and 38 +/- 29 months in Child A and B (P < 0.0001). CONCLUSIONS: The comparable survival of percutaneous alcohol injection-treated patients with single, early hepatocellular carcinoma sorted by nodular size supports the European Association for the Study of the Liver 'wait-and-see' policy for patients with lesions <10 mm, and suggests that allowing the nodules to grow prior to taking further diagnostic or therapeutic actions would not harm these patients.


Asunto(s)
Carcinoma Hepatocelular/terapia , Etanol/administración & dosificación , Cirrosis Hepática/complicaciones , Neoplasias Hepáticas/terapia , Administración Cutánea , Anciano , Carcinoma Hepatocelular/complicaciones , Estudios de Cohortes , Supervivencia sin Enfermedad , Femenino , Humanos , Inyecciones Intralesiones , Neoplasias Hepáticas/complicaciones , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/mortalidad , Análisis de Supervivencia , Resultado del Tratamiento
20.
Aliment Pharmacol Ther ; 22(3): 227-32, 2005 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-16091060

RESUMEN

BACKGROUND: Delta virus (HDV)-related chronic hepatitis is difficult to treat. AIMS: To evaluate the efficacy of lamivudine 100 mg daily on serum HDV-RNA, hepatitis D virus antibodies and alanine aminotransferase levels, liver histology, and on hepatitis B surface antigen seroconversion. METHODS: Thirty-one hepatitis B surface antigen-positive, HDV-RNA-positive patients with ALT > or = 1.5 upper normal level and compensated liver disease were randomized (1:2 ratio) to placebo (group A, n = 11) or lamivudine (group B, n = 20) for 52 weeks; thereafter, all patients were given lamivudine for 52 weeks and followed up for 16 weeks. RESULTS: Twenty-five patients (81%) completed the study. No patient was HDV-RNA-negative at week 52; three patients (11%) were negative at week 104. Two of them remained HDV-RNA-negative at week 120, and one lost the hepatitis B surface antigen without seroconversion. Paired pre-treatment and week 104 liver biopsies were available from 19 patients: of which three of seven (43%) from group A and two of 12 patients (17%) from group B had a > or =2 point decrease in the Ishak necroinflammatory score. CONCLUSION: A sustained complete response was achieved in 8% of hepatitis D virus-infected patients treated with lamivudine and a partial histological response in 26% of them. Hepatitis D virus viraemia was unaffected, even in patients when hepatitis B virus replication was lowered by lamivudine therapy.


Asunto(s)
Antivirales/uso terapéutico , Hepatitis D Crónica/tratamiento farmacológico , Lamivudine/uso terapéutico , Inhibidores de la Transcriptasa Inversa/uso terapéutico , Adulto , Anticuerpos Antivirales/sangre , Método Doble Ciego , Femenino , Antígenos de Superficie de la Hepatitis B/sangre , Hepatitis D Crónica/patología , Hepatitis D Crónica/virología , Virus de la Hepatitis Delta/inmunología , Virus de la Hepatitis Delta/aislamiento & purificación , Humanos , Masculino , Persona de Mediana Edad , ARN Viral/sangre
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...