Figure 1. Positive RANKL-immunoreactivity in stromal cells of ameloblastoma (A), dentigerous cyst (B), odontogenic cyst (C), and radicular cyst (D). Giant cell granuloma served as positive control (E), while the fibro-epithelial polyp served as negative control (F). Positive cells seen in the fibro-epithelial polyp are dendritic cells which are known to express RANKL. Endothelial cells in blood vessels supplying the osteolytic lesions also show positive staining to RANKL (G).