FOXP2 and cancer: At the condition that the tail vein-injected shFOXP2 cells produced more tumors in lung tissues, we observed lower mRNA levels of exogenous human FOXP2, E-cadherin, and PHF2 in the harvested samples of the shROXP2 groups than that of the control groups (Figure 5E), suggesting that the knockdown of FOXP2 and following down-regulated levels of E-cadherin and PHF2 resulted in elevated abilities of metastasis of the cancer cells.