The present technology relates to a method of treating cancer by sensitizing human tumours to DNA damaging therapies through activating FBXO32 expression. Transactivation of FBXO32 through the inhibition of EZH2, a histone methyltransferase, decreases p21 protein induction which results in the sensitization of human tumours to chemotherapy. The method further provides a prognostic method to determine if a combination treatment would be effective.