Both a DNA vaccine against PDGFRβ (Kaplan et al, 2006) as well as PDGFR inhibition by imatinib alone or in combination with irinotecan (Kitadai et al, 2006b), suppressed growth and dissemination of human colorectal cancer cells injected into mice, suggesting that increased PDGF signalling to stromal cells is a determinant for malignancy. Here, PDGFRB is linked to colorectal cancer.