The potential therapeutic targets to bone pain induced by cancer metastasis

About 75-90% of patients with advanced metastatic cancer experience significant cancer pain. Bone cancer pain is one of the most common pains experienced by patients with advanced breast, prostate, or lung cancer. It is characterized by significant skeletal remodeling, fractures, pain, and anemia, all of which reduce the functional status, quality of life, and survival of the patient. Recent years have seen great progress toward alleviating bone pain with the identification of a range of chemicals as well as receptors modulating cancer pain progression. However, the complicated interactions among these factors and, sometimes, the contradicting effects of the same factor in different pathways make it difficult to spot individual effective targets. The sheer quantity of the chemicals involved and the limited understanding from animal models are the constraints in the development of effective therapies for cancer bone pain. In this review, key targets will be discussed along the pain transduction pathway, including peripheral pain sensation, spinal cord transduction pathway, and the central nervous system, to offer a logical and systematic study for the development of combined anti-bone pain treatments.