Interleukin-8 derived from local tissue-resident stromal cells promotes tumor cell invasion.

The aim of this study is to evaluate the role of adipose tissue resident stromal cells on tumor cell invasion. Our data show that a subpopulation of adipose tissue derived stromal cells expressing Nestin, NG2, α-smooth muscle actin and PDGFR-α migrate toward the cancer cells. Microarray analysis revealed the upregulation of IL-8 in the migrated cells. We demonstrated that stromal cell derived IL-8 promote the invasion and the anchorage-independent growth of cancer cells. We conclude that human breast cancer cells attract a subpopulation of stromal cells that secrete IL-8 to promote tumor cell invasion in a paracrine fashion.