Biomedical subjects

Tiziana Del Beato

Publications and source records attributed to Tiziana Del Beato.

6 recordsLinked to original sources

PubMed2006

The study of a patient's immune system may prove to be a useful noninvasive tool for stage classification in colon cancer.

Therapy, and, therefore, prognosis, is strictly related to cancer stage, and hence, screening tests that can contribute to the early classification of disease stage represent a step forward in treatment. Unfortunately, few prognostic indices are available, especially noninvasive ones. Our study of the physiological network of the immune response, however, leads us to believe that it may well be possible to define immunological indices for the classification of cancer stage using blood parameters. In this paper, we show how the study of a patient's immune system can be used as a noninvasive tool for early-stage classification.

CD3 Complex↗

PubMed2006

Are immunological mechanisms involved in colon cancer and are they possible markers for biotherapy improvement?

This paper focuses on our data on colon cancer patients. Our overall results lead us to believe that the suppressive effect of specific cytokines in colon cancer patients alters the functionality of TH1 and TH2 subsets of CD4+ T-cells, with an expansion of TH2 cells and a malfunctioning of TH1 cells. This immunological disregulation appears to increase with stage progression, suggesting a direct role in the mechanisms that allow the tumour to locate and expand within the host. It is also clear that in order to identify disease markers and generate an in vivo immune response that corrects the imbalance between TH1 and TH2 cells, we need to understand how tumour mechanisms cause this imbalance to begin with.

CD4-Positive T-Lymphocytes↗

PubMed2006

Colon cancer and gene alterations: their immunological implications and suggestions for prognostic indices and improvements in biotherapy.

Studies have shown that changes occur in c-Ki-ras, p53, and Bcl2 gene structure and function during the various stages of human colon carcinogenesis. Alterations of these genes are responsible for the establishment of a state of continuous stimulus for cell division and apoptotic inhibition at physiological and pharmacological levels. This paper focuses on the results of our research aimed at investigating how these gene alterations influence tumoral mechanisms on an immunological level and how immunological parameters can be used as prognostic markers for the passage of normal tissue to adenoma and adenoma to carcinoma. Overall, our data suggest that an alteration in the c-Ki-ras gene results in a switch to a suppressive type of immune response, determining an impairment of immune cell activation at both antigen- presenting-cell and T-cell levels. c-Ki-ras gene mutations, p53 deletions, and Bc12 expression, on the other hand, can be used as prognostic markers for the passage of normal tissue to adenoma and adenoma to carcinoma. The p53 oncogene does not appear to impair patients' immunological response further. In conclusion, an evaluation of c-Ki-ras, rather than p53 gene alterations, would seem to be more relevant in colon cancer prevention programs and biotherapy improvement.

Colonic Neoplasms↗

PubMed2005

MICA polymorphism in a population from north Morocco, Metalsa Berbers, using sequence-based typing.

The MICA gene encodes a family of nonclassical major histocompatibility complex class I molecules. Data on MICA polymorphism in different populations are still limited. In the present study, MICA allele frequencies (af) were assessed in 82 unrelated healthy individuals from a Moroccan Berber population named Metalsa (ME) by means of sequence-based typing of exons 2, 3, 4, and 5. In consideration of the linkage disequilibrium existing between MICA and human leukocyte antigen (HLA) class I alleles, MICA/HLA-B, MICA/HLA-Cw, and MICA/HLA-A haplotype frequencies (hf) were estimated. A wide allelic distribution including 16 different MICA alleles was found in ME. The most common MICA alleles were MICA*00801 (af = 0.268), *004 (0.232), *00902 (0.140), *00901 (0.085), and *00901 (0.073). The most common MICA/HLA-B haplotypes were MICA*004-B*4403 and MICA*009-B*50 (hf = 0.113 for both these haplotypes). Some known MICA and HLA-B associations were confirmed in this population. Noteworthy was the high frequency of MICA*009 (af = 0.226); the high frequency of B*50 found in ME (af = 0.114) permitted us to evidence the associations of MICA*00902 with B*5001 (hf = 0.068) or *5002 (hf = 0.045), whereas MICA*00901 was mainly associated with B*5101 (hf = 0.038), which corresponds to the previously described association MICA*009/A6-HLA-B*51. This study extends the previous knowledge on MICA polymorphism to a North African white population and may have implications for disease associations and transplantation.

Adolescent↗

PubMed2002

Sequence-Based analysis of the HLA-DRB1 polymorphism in Metalsa Berber and Chaouya Arabic-speaking groups from Morocco.

To examine the genetic diversity in Morocco, the polymorphism at the HLA-DRB1 locus was investigated in two populations: the Metalsa group consisting of Berbers from north Morocco (who speak the Tarifit language and live in the Nador area), and the Chaouya group who are Arabic-speaking people from west Morocco (Atlantic coast) living in the Settat area. The DRB1 alleles of 197 healthy unrelated individuals were identified by direct DNA sequencing of exon 2 using fluorescently-labeled primers. A total of 28 and 29 alleles at DRB1 locus were identified in the Metalsa and Chaouya groups, respectively. The most frequent alleles in the Metalsa group are DRB1*03011 (20.2%), DRB1*0701 (12.12%), and DRB1*1302 (11.11%). In the Chaouya group, DRB1*0701 (16.33%), DRB1*15011 (12.76%), and DRB1*03011 (11.73%) are most common. Each population exhibits some specific variants and some uncommon alleles. The frequency of the DRB1*03011 allele differs significantly between the two populations (p = 0.0311). The DRB1 frequency distributions in the two groups suggest the effects of balancing selection. The interpopulation analysis highlighted a strong relatedness, based on genetic distances, between the two Moroccan groups and the other north Africans (the Moroccans from El Jadida area, Moroccan Souss Berbers, Algerians, and Tunisians), and to a lesser extent with the Iberians, French, and Ethiopians.

Gene Frequency↗

PubMed2002

Peripheral blood immunological parameters for use as markers of pre-invasive to invasive colorectal cancer.

In cancer, the extent to which the disease has spread is probably the most important factor in determining patient prognosis. Hence practical and non-invasive methods are needed to identify disease stage. In a previous paper we showed how diagnostic and prognostic indices for disease progression could be defined by evaluating parameters in peripheral blood. The aim of this study was to identify further serum parameters that could be used. Serum levels of interferon (IFN) gamma, interleukin (IL)4, IL8, IL7, IL1 beta, tumor necrosis factor (TNF) alpha, granulocyte macrophage-colony stimulating factor (GM-CSF), soluble (s) IL2 receptor (R) and sIL6R were studied but only levels of IL4, sIL2R, IL8 and IL7 were found to be significant and would therefore be of use in defining diagnostic and prognostic indices for disease progression. In further detail, our results indicate that when serum levels of sIL2R < 522 U/ml, IL4 < 159 pg/ml and IL8 > 339 pg/ml there is a 95% probability that the disease is in stage I or II where there is no infiltration of lymph nodes; when serum levels of sIL2R > or = 522 Ug/ml, 159 pg/ml < or = IL4 < or = 319 pg/ml, and IL7 < 54 pg/ml, there is a 95% probability that the disease is in stage III and the tumor has invaded the lymph nodes; when the serum levels of IL4 > or = 431 pg/ml and IL7 > or = 54 pg/ml, there is a 95% probability that the disease is in stage IV and there is metastasis.

Adult↗