Proteases are involved in the invasion and metastasis of tumours by destruction of the basal membrane and connective tissue. As levels in malignant tissue have both prognostic and therapeutic implications, we examined 318 frozen samples from malignant tumours and comparable non-malignant tissue looking for urokinase plasminogen activator (uPA), tissue plasminogen activator (tPA), and plasminogen activator inhibitor-1 (PAI-1) levels with ELISA, as well as cathepsin D with RIA. Oestrogen receptor (ER) levels, progesterone receptor (PrgR) levels and epidermal growth factor receptors (EGFR) were measured by biochemical methods at the same time. Significantly raised levels of uPA, PAI-1 and cathepsin D were found in malignant tissue, with PAI-1 particularly high in carcinoma of the cervix. Significantly raised tPA levels were found in breast cancer tissue with a more favourable clinical prognosis, with a positive correlation between tPA and ER. No correlation could be shown between uPA, PAI-1 and cathepsin D with other prognostic factors for breast cancer. It could be that routine, uncomplicated estimation of tumour-associated proteases such as uPA, tPA, PAI-1 and cathepsin D will provide an independent prognostic marker for therapeutic decisions with regard to gynaecological tumours and breast cancer.

Related Articles