Prospects & Overviews

Inflamm-aging of the stem cell niche: Breast cancer as a paradigmatic example Breakdown of the multi-shell cytokine network fuels cancer in aged people Massimiliano Bonafè1)2), Gianluca Storci1)2)3) and Claudio Franceschi1) Inflamm-aging is a relatively new terminology used to describe the age-related increase in the systemic pro-inflammatory status of humans. Here, we represent inflamm-aging as a breakdown in the multi-shell cytokine network, in which stem cells and stromal fibroblasts (referred to as the stem cell niche) become pro-inflam-matory cytokine over-expressing cells due to the accumulation of DNA damage. Inflamm-aging self-propa-gates owing to the capability of pro-inflammatory cyto-kines to ignite the DNA-damage response in other cells surrounding DNA-damaged cells. Macrophages, the major cellular player in inflamm-aging, amplify the phenomenon, by broadcasting pro-inflammatory signals at both local and systemic levels. On the basis of this, we propose that inflamm-aging is a major contributor to the increase in cancer incidence and progression in aged people. Breast cancer will be presented as a para-digmatic example for this relationship. Keywords:.ageing; cancer; DNA damage; inflammation; stem cell; stem cell nich