For this, we used MPR31-4 murine prostate cancer xenografts growing on Cav1-proficient and Cav1-deficient C57Bl6 mice.44 We show that the recruitment of smooth muscle actin-positive cells to tumor microvessels is defective in Cav1-deficient mice with potential relevance for increased tumor growth. The gene discussed is CAV1; the disease is neoplasm.