In both fruit fly and human systems, loss of boi/CDON results in increased release of Hh or Shh in the absence of cholesterol (Fig. 3D).4,5 Conversely, CDON overexpression can reduce the amount of Shh released under cholesterol stimulation, suggesting that CDON may limit Shh release into the tumor microenvironment. The gene discussed is BOC; the disease is neoplasm.