Indeed, human bone marrow HS5 and primary bone marrow stromal cells were found to be paracrine sources of Wnt3a ligands, and treatment of breast cancer MDA-MB-231 cells with conditioned media derived from these stromal cells enhanced GLI2 levels, which was also associated with an increase in PTHrP (osteolysis mediator) levels and bone destruction. The gene discussed is GLI2; the disease is breast cancer.