The strong inhibition of lung metastasis can be ascribed to the generation of the effector memory T (TEM, CD8+CD44+CD62L−) cells: ICIE significantly increases the effector memory T cells by 2.2 and 2.5 times compared with the CPT&siR CRNPs without cryosurgery on orthotopic tumor and PBS group with cryosurgery on orthotopic tumor, respectively (Fig. 8f and Supplementary Fig. 26b). Here, SELL is linked to neoplasm.