Background: Invasion and metastases of cancer cells and the development of resistance to anticancer therapies are the main causes of treatment failure and mortality in cancer patients.
Methods: We evaluated invasive markers of urokinase plasminogen activator (uPA) and CD44 and multiple drug-resistance (MDR) markers of MDR1 and MRP2 in four epithelial ovarian cancer (EOC) cell lines, primary tumours (n=120) and matched metastatic lesions (n=40) by immunofluoresence labelling. We correlated uPA and CD44 with MDR markers in primary and metastatic cells using confocal microscope. We also investigated the relationship of the expression of uPA, CD44 and MDR1 with various progression parameters.
Results: The coexpression of uPA and CD44 with MDR markers was found in primary and metastatic cells. The overexpression of uPA, CD44 and MDR1 was found in most primary and matched metastatic lesions of EOC, and was significantly associated with tumour stage, grade, residual disease status, relapse and presence of ascites (P<0.05), but not with histology type (P>0.05).
Conclusions: Our results suggest that the overexpression of uPA, CD44 and MRD1 is correlated with EOC progression; both uPA and CD44 are related with drug resistance during EOC metastasis and could be useful therapeutically.