Therapeutic approaches to modulating Notch signaling: current challenges and future prospects.

Dysregulated Notch signaling has been implicated in numerous human diseases, including a broad spectrum of cancers. Mutations in Notch1 are prevalent in T-cell acute lymphoblastic leukemia, and abnormal expression of different human Notch receptors contributes to B-cell tumors as well as cancers of the breast, lung, pancreas, skin, prostate, colon, brain and other tissues. Several γ-secretase inhibitors, small chemical compounds that were initially developed to inhibit the activity of the γ-secretase aspartyl protease in Alzheimer's disease, are now being explored for their potential chemotherapeutic applications in Notch-associated cancers. An alternative approach involves the development of antibodies to inhibit specific Notch receptors, their activating ligands, or other components of the Notch pathway in tumors. Here we review recent progress and current challenges in the use of these strategies to modulate Notch signaling for cancer therapy.