Moreover, high expression of METTL3 was significantly associated with poor OS in esophageal squamous cell carcinoma (HR = 2.20; 95% CI: 1.59–3.05, p < 0.001; I2 = 0.0%, p = 0.436) and oral squamous cell carcinoma (HR = 2.16; 95% CI: 1.33–3.49, p = 0.002; I2 = 0.0%, p = 0.602). The gene discussed is METTL3; the disease is oral cavity squamous cell carcinoma.