While two studies showed no significant correlation between MRP1 and P-gp in gastric cancer, conflicting results were reported in breast cancer (Filipits et al, 1996; Beck et al, 1998; Dexter et al, 1998; Alexander et al, 1999; Fan et al, 2000; Ferrero et al, 2000). The gene discussed is PGP; the disease is breast cancer.