Since LCSE reduced EGFR signaling, downregulated Erk-1/-2 and Akt, and arrested the G1 phase in A549 cells, our results indicated a possible novel role of LCSE in the control of lung adenocarcinoma cells in terms of cell-cycle progression from the G1 phase to the S phase. The gene discussed is AKT1; the disease is lung adenocarcinoma.