Fig. 1.

Contribution of estrogens and androgens to bone remodeling. Estrogen and androgens help to maintain a balance between bone formation and bone resorption. Estrogen inhibits osteoclast activity and contributes to osteoclast apoptosis; androgens are converted to estrogen by aromatization and may also directly affect osteoblast differentiation. As such, a decrease in estrogen and/or androgens leads to increased bone resorption and an imbalance in bone remodeling, which ultimately manifests as bone loss (1–3, 73, 74). Adapted from Skeletal Complications Across the Cancer Continuum CME Lecture 2005 series with permission from the Postgraduate Institute for Medicine.