International Journal of Cancer and Oncology

Cancer-associated muscle dysfunction represents a deadly clinical problem, for which there is currently no treatment. Normal bone remodeling can be disrupted by tumor cells that metastasize to bone in certain stages of cancer, which results in increased morbidity including muscle weakness. The reason for this muscle weakness may be attributed to a reduction in muscle mass and/or a reduction in muscle function. In fact, it has been demonstrated that in advanced cancers, it is probably caused by a combination of reduced quantity and quality of muscle. This review focuses on the mechanisms that bone metastases promote skeletal muscle weakness in metastatic bone disease. Received Date: October 28, 2016 Accepted Date: January 19, 2017 Published Date: January 27, 2017 Citation: Vallet-Regi, M., et al. Mechanisms of Muscle Weakness Associated with Bone Metastases. (2017) Int J Cancer Oncol 4(2): 15. DOI: 10.15436/2377-0902.17.1188 Vallet-Regi, M., et al. vironment is a fertile soil for tumor growth as it houses abundant growth factors which act on tumor cells to fuel growth and other invasive behavior. Bone is a dynamic organ and its homeostasis is maintained by a balanced production of osteoblast and osteoclasts. The relationship between osteoblastic bone formation and osteoclastic bone resorption is balanced in healthy individuals. In various bone diseases including malignancy, disruption of this balance results in the loss of the normal structural integrity of the skeleton[5]. Tumor cells excessively stimulate osteoclasts and osteoblasts, an interaction that is critical for tumor cell survival (Figure 1). Patients with bone metastases have significant morbidity, including bone pain, fracture, hypercalcemia, muscle weakness and spinal cord compression. Cancer patients, who develop bone metastases, can survive for many years, during which they will suffer significant comorbidity; but once cancer metastasizes to bone the tumor is incurable. These comorbidities are known collectively as skeletal-related events (SREs). SREs are associated with impaired mobility, reduced quality of life[6], increased mortality, and higher healthcare costs. Standard antiresorptive