Elucidating the role of molecular signaling pathways in the tumorigenesis of basal cell carcinoma.

The Hedgehog signaling pathway has been identified as fundamentally important to normal embryonic development in living organisms ranging from fruit flies to mammals. Postdevelopmentally, it remains active in hair and skin cells. Abnormal activation of components of the Hedgehog pathway--specifically, resulting from mutations in the Patched 1 gene--is associated with the development of basal cell carcinoma, as well as several other cancers, including medulloblastoma. Patched 1 gene mutation has also been identified as the underlying mechanism in most cases of Gorlin syndrome (also known as basal cell nevus syndrome or nevoid basal cell carcinoma syndrome). Research that resulted in the current understanding of the Hedgehog signaling pathway, in turn, led to multiple lines of investigation to discover mechanisms for halting abnormal signaling, in the hope that agents could be developed that could beneficially stop this pathway. To date, several agents have been developed-and some are in clinical trials-that hold promise for improved nonsurgical treatments for patients with Gorlin syndrome and those with locally advanced/metastatic BCCs.