CXCL12 and breast cancer: In another study, a biomimetic tumoral niche was obtained by using a thin and soft LbL film that presented the SDF1a in a matrix‐bound manner to breast cancer cells.[96] Potent cellular effects could be revealed and previously hidden molecular mechanisms have been identified using this chemokine presentation mode[96] (Figure6), which could not be identified with the soluble SDF1.