Immunofluorescence analysis showed that Ago2 was distributed throughout the nuclei and cytoplasm in normal epithelial cells (i.e., BEAS-2B human lung epithelial cells; Fig. 2C) and was mainly distributed in cytoplasm and membrane of cancer cells (i.e., A549 lung cancer cells; Fig. 2C). The gene discussed is AGO2; the disease is lung carcinoma.