Breast cancer metastasis to the bone: mechanisms of bone loss

Breast cancer frequently metastasizes to the skeleton, interrupting the normal bone remodeling process and causing bone degradation. Osteolytic lesions are the end result of osteoclast activity; however, osteoclast differentiation and activation are mediated by osteoblast production of RANKL (receptor activator for NFκB ligand) and several osteoclastogenic cytokines. Osteoblasts themselves are negatively affected by cancer cells as evidenced by an increase in apoptosis and a decrease in proteins required for new bone formation. Thus, bone loss is due to both increased activation of osteoclasts and suppression of osteoblasts. This review summarizes the current understanding of the osteolytic mechanisms of bone metastases, including a discussion of current therapies

Rethinking Gender, Heterosexual Men, and Women's Vulnerability to HIV/AIDS

Most HIV prevention literature portrays women as especially vulnerable to HIV infection because of biological susceptibility and men's sexual power and privilege. Conversely, heterosexual men are perceived as active transmitters of HIV but not active agents in prevention. Although the women's vulnerability paradigm was a radical revision of earlier views of women in the epidemic, mounting challenges undermine its current usefulness. We review the etiology and successes of the paradigm as well as its accruing limitations. We also call for an expanded model that acknowledges biology, gender inequality, and gendered power relations but also directly examines social structure, gender, and HIV risk for heterosexual women and men