RESUMO
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.
Assuntos
Neovascularização Patológica/metabolismo , Inibidor 1 de Ativador de Plasminogênio/fisiologia , Neoplasias Cutâneas/patologia , Animais , Progressão da Doença , Feminino , Proteínas de Homeodomínio/genética , Proteínas de Homeodomínio/fisiologia , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Mutação/genética , Invasividade Neoplásica/patologia , Estadiamento de Neoplasias , Inibidor 1 de Ativador de Plasminogênio/genética , Neoplasias Cutâneas/irrigação sanguínea , Neoplasias Cutâneas/etiologia , Células Tumorais Cultivadas/química , Células Tumorais Cultivadas/transplanteRESUMO
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.
