Methods and compositions for targeting cancer stem cells
Aspects of the disclosure relate to methods that involve activating the Protein Kinase A (PKA) pathway to induce cancer stem cells (CSCs) to undergo a mesenchymal to epithelial transition. Methods provided herein are useful, in some embodiments, because they render CSCs amenable to treatment with conventional cancer therapies. In some embodiments, methods are provided that involve assaying PKA pathway activity to identify compounds that selectively target CSCs.
1. A method of treating a subject having a carcinoma, the method comprising:
administering to the subject a Protein Kinase A (PKA) pathway activator in an amount sufficient to induce cancer stem cells of the carcinoma to undergo a mesenchymal to epithelial transition;
wherein the subject is administered the PKA pathway activator within 1 hour, 1 day, 1 week, 1 month or more prior to being administered a chemotherapeutic agent and/or radiotherapy.
2. The method of claim 1 , further comprising administering to the subject an effective amount of the chemotherapeutic agent and/or radiotherapy.
3. The method of claim 1 , wherein the PKA pathway activator induces adenylyl cyclase activity, thereby increasing cyclic AMP (cAMP) levels in the cells.
4. The method of claim 1 , wherein the PKA pathway activator is selected from cholera toxin, forskolin, colforsin daropate (CD) and derivatives of any one of them.
5. The method of claim 1 , wherein the chemotherapeutic agent is a DNA intercalating agent or a mitotic inhibitor.
6. The method of claim 5 , wherein the mitotic inhibitor comprises paclitaxel, docetaxel, vinblastine, vincristine, and/or vinorelbine.