CXCR4 and adrenal cortex carcinoma: CXCL12, the gene encoding the CXCL12 chemokine, was not among the genes whose expression correlated with CXCR4. Additionally, staining of 15 of the ACC cases for CXCL12 by IHC, 10 of which were CXCR4+ by IHC (data not shown), failed to reveal CXCL12 in cancer cells.