Furthermore, chemokines were found to have vital roles in cell–cell interaction by recruitment and activation of different cell types to tumor sites via autocrine or paracrine mechanisms.15, 16 The chemokines expressed in stromal cells were demonstrated to be implicated in tumor growth, metastasis and angiogenesis.15 In ESCC, several chemokines including CXCL12, CXCL8 and CXCL10 were discovered as potential tumor biomarkers.17 Some of these chemokines significantly correlated with tumor size, lymph node involvement and distant metastases of ESCC patients. The gene discussed is CXCL12; the disease is esophageal squamous cell carcinoma.