Analysis of a bone metastasis gene expression signature in patients with bone or non-bone metastases from solid tumors.

e21054 Background: Using human breast cancer (BC) cells in a mouse model, Kang et al. reported a bone metastasis (BM) gene signature. The BM-related genes encode secretory and cell surface proteins implicated in bone-homing (CXCR4), angiogenesis (CTGF and FGF5), invasion (MMP-1 and ADAMTS1), and osteoclast recruitment (IL-11). ADAMTS1, CTGF and IL-11 were found to be overexpressed in the primary of BC with BMs. We analyzed the expression of the six BM-related genes plus OPN, in patients with BC and bone or non-bone metastases (BCBMs and BCNBMs, respectively) and BMs from other solid tumors (OSTBMs), to assess its relevance in human clinical samples. Methods: Eleven BMs (BC: 3; OST: 8) and four BCNBMs (liver; lung; skin; lymph node) were analyzed. Areas with ≥80% tumor cells were dissected from cryosections. Gene expression was analyzed by RT-qPCR, and normalized for GADPH. The BC cell line MDA-MB-231 and the normal breast epithelium cell line MCF10A were used for experimental validation. Differences betwe...