Some cancer cells act in a similar way to stem cells when it comes to reproducing and sustaining a tumor. These cancer stem cells are believed to be the engine behind the growth, spread, and reoccurrence of tumors. Stopping or interfering with their action may also lower the resistance to cancer treatment.
By using the antibiotic doxycycline, cells are inhibited to switch their fuel source and they are left with glucose as their only source of energy. When followed with ascorbic acid (Vitamin C), which removes the glucose, cancer stem cells are effectively starved to death.