Basal Cell Carcinoma and Patched

Basal Cell Carcinoma is the most common skin cancer, and possibly the most common cancer of all http://www.skincancer.org/basal/index.php

Normal Skin Cells Basal Cell Carcinoma

Like most skin cancers, BCC is primarily caused by sun exposure, specifically UVB rays These rays cause mutations in DNA including deletions and substitutions

The Patched gene is a tumor suppressor, like Retinoblastoma Therefore, both copies of Patched must be mutated in order to cause a tumor

Nevoid Basal Cell Carcinoma is the inherited form of the patched mutation, and results in tumor formation in many tissues http://www.dermoncology.com/tumors/tumor%20albums/b6.htm

The Sonic Hedgehog-Patched Pathway Shh Ptch Smo Cytoplasm Microtubules Gli1 Nucleus

The Sonic Hedgehog pathway is involved in many processes, most importantly in midline patterning and dorsal-ventral nervous system development www.jhu.edu/~jhumag/0297web/ scitech.html

Veratrum californicum (California False Hellebore) Contains an alkaloid called cyclopamine Cyclopamine binds directly to Smo and inhibits the Shh pathway www.csdl.tamu.edu/FLORA/ imaxxmln.htm

Cyclopia in sheep muvetmed.agr.iwate-u.ac.jp/.../ tenji/tenji9.html

When Ptch is mutated, it turns the pathway on without binding Shh- more patched is transcribed Smo Cytoplasm Microtubules Gli1 Nucleus

Possible Treatments Cyclopamine, and is currently in clinical trials Patched itself can also inhibit this pathway, and has been effective in mice with BCC