Fig. 1From: Neutrophils in triple-negative breast cancer: an underestimated player with increasingly recognized importanceNeutrophils help CTCs survive, proliferate, and metastasize. Interactions with neutrophils enhance the survival, proliferation, and metastasis of circulating tumor cells (CTCs) in the bloodstream. Expression of vascular cell adhesion molecule 1 (VCAM1) in cancer cells mediates the formation of CTC–neutrophil clusters, through binding to specific integrins such as α3β1 integrin on neutrophils. CTCs also express G-CSF to stimulate the pro-tumor functions of neutrophils. In turn, neutrophils clustered with CTCs secrete cytokines such as IL-1β and IL-6, which promote CTC survival and proliferation through increased expression of Ki67Back to article page