In situ hybridization for DLX5 and DLX6 in MDA-MB-231 bone metastases. (A) A bone metastasis, visualized by radiography. (B and C) In-situ hybridization on sections of long bones containing MDA-MB-231 metastases showing high expression of DLX5 and DLX6. The signal was more intense at the invasion front (arrows). bn, cortical bone; met, metastasis.