UROKINASE PLASMINOGEN ACTIVATOR (uPA) AND PLASMINOGEN ACTIVATOR INHIBITOR TYPE-1 (PAI-1) IN BREAST CANCER – CORRELATION WITH TRADITIONAL PROGNOSTIC FACTORS
Background: Urokinase plasminogen activator (uPA) and plasminogen activator inhibitor type-1 (PAI-1) play a key role in tumour invasion and metastasis. High levels of both proteolytic enzymes are associated with poor prognosis in breast cancer patients. The purpose of this study was to evaluate the association between traditional prognostic factors and uPA and PAI-1 expression in primary tumour of breast cancer patients.
Methods: 606 primary breast cancer patients were enrolled in the prospective study in the Department of gynaecological oncology and breast oncology at the University Medical Centre Maribor between the years 2004 and 2010. We evaluated the traditional prognostic factors (age, menopausal status, tumour size, pathohistological type, histologic grade, lymph node status, lymphovascular invasion and hormone receptor status), together with uPA and PAI-1. We used Spearman's rank correlation, Mann Whitney U test and χ2 test for statistical analysis.
Results: Our findings indicate a positive association between uPA and tumour size (p < 0.001), grade (p < 0.001), histological type (p < 0.001), lymphovascular invasion (p = 0.01) and a negative association between uPA and hormone receptor status (p < 0.001). They also indicate a positive association between PAI-1 and tumour size (p = 0.004), grade (p < 0.001), pathohistological type (p < 0.001) and negative association between PAI-1 and hormone receptor status (p = 0.002).
Conclusions: Our study showed a relationship between uPA and PAI-1 and traditional prognostic factors. Their role as prognostic and predictive factors remains to be further evaluated.
Key words urokinase plasminogen activator; plasminogen activator inhibitor; breast cancer; prognostic factor