CXCR4 and head and neck squamous cell carcinoma: Recent work by Hersi et al. showed that low expression of the tumour-suppressive miR-9, which targets the CXCL12 receptor CXCR4, was linked to aggressive behaviour of HNSCC cells, counteracted by targeting of this interaction with Plerixafor (a CXCR4 inhibitor)178.