To further explore the effect of NKCC1 on tumor metastasis in vivo, we injected NKCC1-overexpressed MHCC97L cells and control cells transfected with empty vector (2×106 cells) into the tail veins of nude mice, and checked extrahepatic metastasis in the lungs after 16 weeks. The gene discussed is SLC12A2; the disease is neoplasm.