Disclosed are methods and compositions for modulating cancer stem cells. More particularly, the present invention discloses the use of protein kinase C theta inhibitors (PKC-θ) for inhibiting the growth of PKC-θ-overexpressing cells including cancer stem cells, for enhancing the biological effects of chemotherapeutic drugs or irradiation on cancer cells, for treating cancer, including metastatic cancer and/or for preventing cancer recurrence.
