Summary It is now clearly established that proteolytic enzymes, including plasminogen activator (uPA), play an important role in breaking down the extracellular matrix, which is considered to be a step in metastasis formation. Plasminogen activators are controlled at various levels. Two inhibitors, PAI-1 and PAI-2, have been identified, the latter being more specific for uPA. In attempts to determine their prognostic value, it is essential to investigate the relative importance of these parameters and their interactions. We used an immunoenzymatic method to assay uPA, PAI-I and PAI-2 antigens in cytosols prepared from 314 primary breast tumours. The patients were followed up for a minimum of 6 years and all relevant clinical and laboratory findings were recorded. Univariate analysis confirmed the poor outcome of patients whose tumours contained large amounts of uPA and PAI-1. In addition, low levels of PAI-2 correlated with shorter disease-free survival in the overall population (P= 0.02), post-menopausal women (P= 0.02) and women without lymph node involvement (P = 0.02). Multivariate analysis in the 'main effects' Cox model identified node involvement, macroscopic tumour size and PAI-2 as significant variables. The 'interactive' model, taking into account interactions between uPA and its two inhibitors, identified a first subgroup with a very poor prognosis associating either high levels of PAI-I with low levels of PAI-2 in the overall population and the women with no node involvement or high levels of uPA with low levels of PAI-2 in the group of menopausal women. We conclude that PAI-I provides the same prognostic information as uPA, and does not appear to play a role as an inhibitor. In contrast, PAI-2 increases the prognostic value of uPA, particularly in post-menopausal women, and PAI-1 in patients with no node involvement.

Purpose:Although a potential role of the Epstein-Barr virus (EBV) in the pathogenesis of breast cancer (BC) has been underlined, results remain conflicting. Particularly, the impact of EBV infection on biological markers of BC has received little investigation.Methods:In this study, we established the frequency of EBV-infected BC using real-time quantitative PCR (RT–PCR) in 196 BC specimens. Biological and pathological characteristics according to EBV status were evaluated.Results:EBV DNA was present in 65 of the 196 (33.2%) cases studied. EBV-positive BCs tended to be tumours with a more aggressive phenotype, more frequently oestrogen receptor negative (P=0.05) and with high histological grade (P=0.01). Overexpression of thymidine kinase activity was higher in EBV-infected BC (P=0.007). The presence of EBV was weakly associated with HER2 gene amplification (P=0.08).Conclusion:Our study provides evidence for EBV-associated BC undergoing distinct carcinogenic processes, with more aggressive features.

Glioblastoma (GBM) is a highly malignant glioma, which has the propensity to infiltrate throughout the brain in contrast to pilocytic astrocytoma (PA) of the posterior fossa, which does not spread and can be cured by surgery. We have used Suppression Subtractive Hybridization to define markers that better delineate the molecular basis of brain invasion and distinguish these tumor groups. We have identified 106 genes expressed in PA versus GBM and 80 genes expressed in GBM versus PA. Subsequent analysis identified a subset of 20 transcripts showing a common differential expression pattern for the two groups. GBM differs from PA by the expression of five genes involved in invasion and angiogenesis: fibronectin, osteopontin, chitinase-3-like-1 (YKL-40), keratoepithelin and fibromodulin. PA differs from GBM by the expression of genes related to metabolism (apolipoprotein D), proteolysis (protease-serine-11), receptor and signal transduction (PLEKHB1 for Pleckstrin-Homology-domain-containingprotein-family-B-member-1), transcription/translation (eukaryotic-translation-elongation-factor-1-a1) processes and cell adhesion (SPOCK1 for SPARC/Osteonectin-CWCV-kazal-like-domains-proteoglycan). The expression of these genes was confirmed by real-time quantitative RT-PCR and immunohistochemistry. This study highlights the crucial role of brain invasion in GBM and identifies specific molecules involved in this process. In addition, it offers a restricted list of markers that accurately distinguish PA from GBM.