The present invention relates to a pharmaceutical composition of PRCP antagonist, PREP antagonist, or PRCP-PREP dual antagonist. The present invention also relates to a pharmaceutical composition jointly using PRCP antagonist and mTOR antagonist, or jointly using PREP antagonist and mTOR antagonist, or jointly using PRCP-PREP dual antagonist and mTOR antagonist. In addition, the present invention also relates to a method for utilizing the pharmaceutical compositions to treat and prevent cancers and diseases related to insulin receptor substrate protein and PI3K/AKT/mTOR signal pathway.
