CXCL12 and non-small cell lung carcinoma: Finally, the two meta-analyses that have evaluated the overall effects of CXCL12/CXCR4 expression in NSCLC have reported that CXCR4 expression is closely associated with lymph node metastasis (OR = 3.79, 95% CI: 2.15–6.68), distant metastasis (OR = 3.67, 95% CI: 1.84–7.32), tumor stage (OR = 2.78, 95% CI: 1.77–4.39) and overall survival (HR = 1.63, 95% CI: 1.16–2.30).