RESUMEN
Angiogenesis and tumor expansion are associated with extracellular matrix remodeling and involve various proteases such as the plasminogen (Plg)/plasminogen activator (PA) system. Recently, several experimental data have implicated the plasminogen activator inhibitor-1 (PAI-1) in tumor angiogenesis in murine systems. However, little is known about PAI-1 functions in human skin carcinoma progression. By generating immunodeficient mice (in Rag-1-/- or nude background) deleted for PAI-1 gene (PAI-1-/-), we have evaluated the impact of host PAI-1 deficiency on the tumorigenicity of two malignant human skin keratinocyte cell lines HaCaT II-4 and HaCaT A5-RT3 forming low-grade and high-grade carcinomas, respectively. When using the surface transplantation model, angiogenesis and tumor invasion of these two cell lines are strongly reduced in PAI-1-deficient mice as compared to the wild-type control animals. After subcutaneous injection in PAI-1-/- mice, the tumor incidence is reduced for HaCaT II-4 cells, but not for those formed by HaCaT A5-RT3 cells. These data indicate that PAI-1 produced by host cells is an important contributor to earlier stages of human skin carcinoma progression. It exerts its tumor-promoting effect in a tumor stage-dependent manner, but PAI-1 deficiency is not sufficient to prevent neoplastic growth of aggressive tumors of the human skin.
Asunto(s)
Neovascularización Patológica/metabolismo , Inhibidor 1 de Activador Plasminogénico/fisiología , Neoplasias Cutáneas/patología , Animales , Progresión de la Enfermedad , Femenino , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/fisiología , Humanos , Masculino , Ratones , Ratones Endogámicos C57BL , Mutación/genética , Invasividad Neoplásica/patología , Estadificación de Neoplasias , Inhibidor 1 de Activador Plasminogénico/genética , Neoplasias Cutáneas/irrigación sanguínea , Neoplasias Cutáneas/etiología , Células Tumorales Cultivadas/química , Células Tumorales Cultivadas/trasplanteRESUMEN
Immuno-polymerase chain reaction (PCR) is an extremely sensitive detection method, combining the specificity of antibody detection and the sensitivity of PCR. We have developed an immuno-quantitative PCR (iqPCR), exploiting real-time PCR technology, in order to improve this immuno-detection method and make it quantitative. To illustrate the advantages of iqPCR, we have compared it with a conventional enzyme linked immuno sorbent assay (ELISA) technique in experiments aimed at detecting the cellular and the resistant form of prion protein in bovine brain extract. The iqPCR technique proved to be more sensitive than ELISA, so it could be a technique of choice for the diagnosis of infected animals both at an ante mortem and post-mortem stage.