As showed in Fig. 5, lower expression of SLC4A4 obviously correlated with OS, RFS, PPS, DMPS of patients with breast cancer (Fig. 5A, P<0.05), OS, FP and PPS of patients with lung cancer (Fig. 5B, P<0.05) and gastric cancer (Fig. 5C, P<0.05), as well as OS, PFS and PPS of patients with ovarian cancer (Fig. 5D, P<0.05). The gene discussed is SLC4A4; the disease is lung cancer.