Studying the role of IL-8-dependent changes of tumor cell invasion in vitro, however, is subject to significant limitations and requires relevant 3D models as (i) cellular IL-8 expression/secretion is significantly reduced in monolayer culture relative to in vivo scenarios24 and (ii) tumor cells respond to IL-8 with increased migration/invasion in 3D, but not in 2D cultures25. The gene discussed is CXCL8; the disease is neoplasm.