The present invention provides methods of inhibiting angiogenesis in a malignant tumor, inhibiting metastasis of a malignant tumor and of inhibiting transformation of a benign tumor to a malignant tumor. The present invention also provides assays for identifying inhibitors of angiogenesis in a malignant tumor, inhibitors of metastasis of a malignant tumor and of inhibitors of transformation of a benign tumor to a malignant tumor.