CXCL12 and ovarian cancer: A previous study showed that expression of cytokine C-X-C chemokine ligand 12 (CXCL12), known as stromal-derived factor 1 (SDF-1), was the most significant biomarker predictive of survival on the basis of multiple microarray analyses measuring the expression of ~17,000 genes and 341 miRNAs across 2129 ovarian cancer samples [145].