NF1 and undifferentiated pleomorphic sarcoma: Our data showed that the NF1 expression was decreased, but the protein expressions of p-Akt, p-mTOR, and p-S6 were significantly higher in the UPS sarcoma tissue than those in the adjacent normal tissue, which confirmed and verified that the NF1-inhibited PI3K-Akt-mTOR-S6 signal pathway was associated with the occurrence and growth of UPS.