Breast cancer metastasis

The most lethal attribute of a cancer cell is its ability to metastasize. In a post-mortem evaluation of 358 cancer patients, Walther found that after lung and liver, bone is the third most prevalent site of metastases. In breast carcinomas bone is one of the most common sites of distant metastases. In patients with bone metastasis, complications may be manifested in osteolysis, spinal cord compression, hypercalcemia, increased fracture incidence and unrelenting pain. Furthermore, patients with bone metastasis are seldom cured. Clearly, the prevention of metastasis should, at the very least, improve the quality of life for the patient and may increase survival rates. Unfortunately, an incomplete understanding of breast cancer metastasis to bone has hindered development of effective treatments specifically targeting metastasis. In this review we discuss a working hypothesis we are developing that suggests connexin expression profiles and heterotypic gap junctional communication between breast cancer cells contributes to the mechanism by which breast cancer cells metastasize to bone.