The role of CXCR6 in human glioma cells is controversial: high expression of CXCL16 has been reported in several human GBM cell lines, as well as in human glioma tissues (TCGA database), in contrast to a very low, sometimes almost undetectable, expression of CXCR6 (21). The gene discussed is CXCL16; the disease is glioma.