Vicente Madrid-Marina

Cervical cancer development from a squamous intraepithelial lesion is thought to be favored by an impaired T cell immunity. We evaluated parameters of T cell alterations such as proliferation, cytokine, and CD3ζ expression in peripheral blood and tumor-infiltrating T lymphocytes from women with squamous intraepithelial lesions (SIL) or cervical cancer (CC). T cell proliferation and cytokine messenger RNA (mRNA) expression were similar in women with SIL and healthy donors, whereas low T cell proliferation and lower mRNA expression of IL-2, IL-10 and IFN-γ were observed in women with CC. Moreover, infiltrating cells showed marginal responses. We also found that CD3ζ mRNA expression, whose protein is required for T cell activation, correlated with a decreased proliferation in advanced stages of the disease. Experiments with T cells from healthy donors in the presence TGF-β1 or IL-10 suggest that these cytokines have a relevant role in T cell responses during CC progression.

Objective: Our aims were to examine the ability of the human papillomaviruse (HPV) 16 E2 protein to induce apoptosis in a murine HPV-transformed cell line, and to evaluate its antitumor properties on HPV-associated tumors in vivo in immunocompetent mice. Methods: HPV-transformed murine BMK-16/myc cells and human SiHa cells were transfected with the HPV 16 E2 gene to examine the effects of the E2 protein on cell growth and on the E6 and E7 oncogenes as well as DNA fragmentation and activation of the extrinsic pathway of apoptosis. Finally, to test the antitumor effect of the E2 protein on an experimental mouse tumor model, we generated a recombinant adenovirus expressing the E2 protein. Results: The E2 protein inhibited the growth of SiHa and BMK-16/myc cell lines, and repressed the E6 and E7 oncogenes. Moreover, the E2 protein induced DNA fragmentation and apoptosis through activation of caspases 8 and 3 in BMK-16/myc cells. On the other hand, E2 also showed antitumor effects in vivo. Conclusions: Our findings indicate that E2 exerts pro-apoptotic activity in a murine HPV-transformed cell line as well as an antitumor effect in vivo. Copyright (C) 2009 S. Karger AG, Basel

Genomics, as a scientific discipline responsible for genome maps, sequencing and functional analysis of genomes, allows for continually expanding knowledge of the structure and function of genomes. The influence of genomics on medicine generates a new perspective for how we perceive health and disease, knowing the influence of genetic variations on susceptibility to disease. In the area of public health, genetic epidemiology translates genetic knowledge into individual and public actions, evaluating the effect of the distribution of genetic determinants and their interaction with environmental factors involved in the etiology of human diseases. In addition, genomic medicine suggests new diagnostic systems, genetic associations and nutritional disorders, specific responses to diverse drugs, and the design of new drugs for susceptible groups. And yet, the greatest advances in genomic medicine in the field of health are forthcoming.

Gene therapy is an excellent alternative for treatment of many diseases. Capacity to manipulate the DNA has allowed direct the gene therapy to correct the function of an altered gene, to increase the expression of a gene and to favour the activation of the immune response. This way, it can intend the use of the DNA like medication able to control, to correct or to cure many diseases. Gene therapy against cancer has an enormous potential, and actually the use of the DNA has increased to control diverse cancer in animal models, with very encouraging results that have allowed its applications in experimental protocols in human. This work concentrates a review of the foundations of the gene therapy and its application on cervical cancer, from the point of view of the alterations of the immune system focused on the tumour micro-environment, and the use of the cytokines as immunomodulators.

Summary: Terminal deoxynucleotidyl transferase (TdT) is a template‐independent DNA polymerase that catalyses the incorporation of deoxyribonucleotides into the 3′‐hydroxyl end of DNA templates and is thought to increase junctional diversity of antigen receptor genes. TdT is expressed only on immature lymphocytes and acute lymphoblastic leukaemia cells and its transcriptional expression is tightly regulated. We had previously found that protein kinase C (PKC) activation down‐regulates TdT expression. PKC‐activation induces the synthesis of the Fos and Jun proteins, known as the major components of activation protein 1 (AP‐1) transcriptional factor implicated in transcriptional control. Here we report the identification of several DNA–protein interactions within the TdT promoter region in non‐TdT expressing human cells. Sequence analysis revealed the presence of a putative AP‐1‐like DNA‐binding site, suggesting that AP‐1 may play a relevant role in TdT transcriptional regulation. Using a different source of nuclear extracts and the AP‐1–TdT motif as a probe we identified several DNA‐protein retarded complexes in electrophoretic mobility shift assays. Super‐band shifting analysis using an antibody against c‐Jun protein confirmed that the main interaction is produced by a nuclear factor that belongs to the AP‐1 family transcription factors. Our findings suggest that the TdT gene expression is down‐regulated, at least in part, through AP‐1‐like transcription factors.

Intrathymic development and selection of the T lymphocyte repertoire is restricted by the interactions of the T cell antigen receptor and CD4 or CD8 co-receptors with self major histocompatibility complex molecules. Positive or negative selection depends on a tight regulatory control of CD4 and CD8 expression. Determining the intracellular signals that differentially regulate the expression of CD4 and CD8 is important to understand the mechanisms that are implicated in selection of single positive CD4+CD8- or CD4-CD8+. The present study shows that stimulation of human thymocytes by phorbol esters or cAMP result in a differential regulation of CD4 and CD8 expression, both at the mRNA and cell surface glycoprotein level. The differential regulation of CD4 and CD8 gene expression suggests that the selective activation of protein kinase C (PKC) and cAMP-dependent protein kinases (PKA) may be required for the selection of single positive CD4+CD8- and CD4-CD8+ cells during Intrathymic differentiation