QUALITY-CONTROL OF IMMUNOHISTOCHEMICAL EVALUATION OF TUMOR-ASSOCIATEDPLASMINOGEN ACTIVATORS AND RELATED COMPONENTS

The plasminogen activation (PA) system is involved in the breakdown an d remodelling of the extracellular matrix. In the case of cancer, this is a prerequisite for invasion and metastasis. The expression of urok inase-type plasminogen activator and plasminogen activator inhibitor t ype 1 in particular have been reported to be of clinical and prognosti c value. This has primarily been proven in the case of breast carcinom a and colon carcinoma, using the enzyme-linked immunosorbent assay (EL ISA) as a quantitative assay to determine the level of expression. Imm unohistochemistry is another technique to investigate the presence of PA components. It allows assessment in a semiquantitative way and info rms in addition on the specific distribution within the tissue. To tak e full advantage of the benefits of immunohistochemistry, it is import ant to aim at optimal quality in all steps influencing the final judge ment of the staining results. These various steps are highlighted and discussed in this paper. (C) 1998 Elsevier Science Ltd. All rights res erved.