Caracterización de ratones rxra condicionales que expresan los oncogenes e6/e7 del hpv16, como modelo para el estudio de la carcinogénesis cervical

Tesis (Maestría en Ciencias en Biomedicina Molecular), Instituto Politécnico Nacional, SEPI, ENMH, 2009, 1 archivo PDF, (63 páginas). tesis.ipn.m

Efecto cooperador de e6e7hpv16 y la ausencia de rxra en la carcinogenesis cervical en ratones triple transgénicos

Tesis (Maestría en Ciencias en Biomedicina Molecular), Instituto Politécnico Nacional, SEPI, ENMH, 2012, 1 archivo PDF, (93 páginas). tesis.ipn.m

Impaired cervical homeostasis upon selective ablation of RXRalpha in epithelial cells.

International audienceRetinoids play critical regulatory roles in the maintenance of mammalian epithelia and exert pleiotropic effects through nuclear receptors. RXRalpha, which is a ligand-dependent transcription factor, is the most abundant RXR isotype expressed in cervical epithelia, and may play a crucial role in cervix development and homeostasis. We have previously described a mouse model to induce the temporally controlled epithelia-specific somatic mutagenesis of RXRalpha alleles in epidermis. To study the role of RXRalpha in cervical homeostasis, we ablated RXRalpha in cervix epithelial cells of adult mice. We found that such mutant mice develop ectocervical atrophy with moderate epidermoid metaplasia. In addition, we report a simultaneous increase of cell proliferation and apoptosis levels accompanied by alteration in the expression of genes involved in both processes

The HPV16 E7 Oncoprotein Disrupts Dendritic Cell Function and Induces the Systemic Expansion of CD11b+Gr1+ Cells in a Transgenic Mouse Model

Objective. The aim of this study was to analyze the effects of the HPV16 E7 oncoprotein on dendritic cells (DCs) and CD11b+Gr1+ cells using the K14E7 transgenic mouse model. Materials and Methods. The morphology of DCs was analyzed in male mouse skin on epidermal sheets using immunofluorescence and confocal microscopy. Flow cytometry was used to determine the percentages of DCs and CD11b+Gr1+ cells in different tissues and to evaluate the migration of DCs. Results. In the K14E7 mouse model, the morphology of Langerhans cells and the migratory activity of dendritic cells were abnormal. An increase in CD11b+Gr1+ cells was observed in the blood and skin of K14E7 mice, and molecules related to CD11b+Gr1+ chemoattraction (MCP1 and S100A9) were upregulated. Conclusions. These data suggest that the HPV16 E7 oncoprotein impairs the function and morphology of DCs and induces the systemic accumulation of CD11b+Gr1+ cells

<it>In situ</it> molecular identification of the Influenza A (H1N1) 2009 Neuraminidase in patients with severe and fatal infections during a pandemic in Mexico City

Abstract Background In April 2009, public health surveillance detected an increased number of influenza-like illnesses in Mexico City’s hospitals. The etiological agent was subsequently determined to be a spread of a worldwide novel influenza A (H1N1) triple reassortant. The purpose of the present study was to demonstrate that molecular detection of pandemic influenza A (H1N1) 2009 strains is possible in archival material such as paraffin-embedded lung samples. Methods In order to detect A (H1N1) virus sequences in archived biological samples, eight paraffin-embedded lung samples from patients who died of pneumonia and respiratory failure were tested for influenza A (H1N1) Neuraminidase (NA) RNA using in situ RT-PCR. Results We detected NA transcripts in 100% of the previously diagnosed A (H1N1)-positive samples as a cytoplasmic signal. No expression was detected by in situ RT-PCR in two Influenza-like Illness A (H1N1)-negative patients using standard protocols nor in a non-related cervical cell line. In situ relative transcription levels correlated with those obtained when in vitro RT-PCR assays were performed. Partial sequences of the NA gene from A (H1N1)-positive patients were obtained by the in situ RT-PCR-sequencing method. Sequence analysis showed 98% similarity with influenza viruses reported previously in other places. Conclusions We have successfully amplified specific influenza A (H1N1) NA sequences using stored clinical material; results suggest that this strategy could be useful when clinical RNA samples are quantity limited, or when poor quality is obtained. Here, we provide a very sensitive method that specifically detects the neuraminidase viral RNA in lung samples from patients who died from pneumonia caused by Influenza A (H1N1) outbreak in Mexico City.</p

HPV16-E6 Oncoprotein Activates TGF-β and Wnt/β-Catenin Pathways in the Epithelium-Mesenchymal Transition of Cataracts in a Transgenic Mouse Model

Objective. This work aimed to determine if cataractous changes associated with EMT occurring in the K14E6 mice lenses are associated with TGF-β and Wnt/β-catenin signaling activation. Materials and Methods. Cataracts of K14E6 mice were analysed histologically; and components of TGF-β and Wnt/β-catenin signaling were evaluated by Western blot, RT-qPCR, in situ RT-PCR, IHC, or IF technics. Metalloproteinases involved in EMT were also assayed using zymography. The endogenous stabilisation of Smad7 protein was also assessed using an HDAC inhibitor. Results. The K14E6 mice, which displayed binocular cataracts in 100% of the animals, exhibited loss of tissue organisation, cortical liquefaction, and an increase in the number of hyperproliferative-nucleated cells with mesenchymal-like characteristics in the lenses. Changes in lenses’ cell morphology were due to actin filaments reorganisation, activation of TGF-β and Wnt/β-catenin pathways, and the accumulation of MTA1 protein. Finally, the stabilisation of Smad7 protein diminishes cell proliferation, as well as MTA1 protein levels. Conclusion. The HPV16-E6 oncoprotein induces EMT in transgenic mice cataracts. The molecular mechanism may involve TGF-β and Wnt/β-catenin pathways, suggesting that the K14E6 transgenic mouse could be a useful model for the study or treatment of EMT-induced cataracts