Nanog overexpression was significantly related to differentiation (poor and undifferentiation versus well and moderate differentiation: OR = 4.17, 95% CI = 2.71-6.43, P ≤ 0.001, fixed effect, Figure 4(a)), lymph node metastasis (YES versus NO: OR = 1.76, 95% CI = 1.06-2.91, P = 0.028, fixed effect, Figure 4(b)), and tumor size (≥3cm versus < 3cm: OR = 1.93, 95% CI = 1.17-3.20, P = 0.010, fixed effect, Figure 4(c)). This evidence concerns the gene NANOG and neoplasm.