The present invention relates to the identification of new drug targets for therapy of disorders including cancer. In particular, the present invention relates to inhibition of the E3 ubiquitin ligase, Itch, as a means for treating disorders. Furthermore, the present invention relates to the regulation of p63 and p73 stability in cells. In particular, the invention relates to the modulation of the regulation of p63 and p73 stability in cells through modulation of the expression or activity of Itch. Moreover, the invention relates to the use of Itch as a target for the development of agents capable of modulating p63 or p73 stability and especially agents capable of modulating the interaction of Itch and p63 and p73. Such agents may be useful in therapeutic applications including cancer treatment and modulation of skin differentiation.