The present invention demonstrates that P2X7 receptor induced apoptosis may be specific for cancerous cells. Treatment with the P2X7 ligand BzATP, increased cellular apoptosis with no associated inflammatory changes or abnormal skin or systemic effects. In mice treated with DMBA/TPA, BzATP decreased papilloma skin formation. BzATP also induced involution of developed papillomas and stimulated apoptosis in keratinocytes outgrowing at the base of developed papillomas. These data show that (a) P2X7 regulates apoptosis of epidermal cells (b) in vivo, local administration of a drug that activates the P2X7 receptor can inhibit development and progression of epidermal premalignant lesions.
