Previously, we have shown that CXCR4 mediates important functions for SCLC metastasis to stromal microenvironments, for example adhesion of SCLC cells to immobilised extracellular matrix proteins and stromal cells by activation of β1-integrins, leading to cell adhesion-mediated drug resistance that protects SCLC cells from chemotherapeutic treatment (Sethi et al, 1999; Burger et al, 2003; Hartmann et al, 2005). Here, CXCR4 is linked to small cell lung carcinoma.