However, expression level of SMAD6 was significantly correlated with OS of all gastric cancer patients (HR = 1.42 (1.19–1.71), P = 0.00014 (Figure 6(a)) and gastrointestinal cancer patients (HR = 1.56 (1.05–2.31), P = 0.026 (Figure 6(b)). The gene discussed is SMAD6; the disease is gastric cancer.