Multidrug resistance proteins and topoisomerase IIalpha expression in colon cancer: association with metastatic potential

To investigate the role of multidrug resistance proteins and topoisomerase IIalpha in colon cancer. Tissue sections from 89 Dukes' stage B-D colon cancer patients were selected. The expression of multidrug resistance proteins and topoisomerase IIalpha in primary tumour cells was assessed by standard immunohistochemistry. The extent of their expression was measured by image analysis and was correlated with clinicopathological features of the patients. P-glycoprotein was associated with the presence of lymph node metastasis (P=0.005), vessel invasion (P=0.0001) and perineural invasion (P=0.020). P-glycoprotein is probably involved in the processes of local invasion and metastatic dissemination.