Preferred Label : Ptc1 Regulation of Cell Cycle Pathway;
NCIt related terms : Sonic Hedgehog (SHH) Receptor Ptc1 Regulates cell cycle;
Alternative definition : BIOCARTA: Sonic Hedgehog (Shh) is a secreted protein identified genetically as an
important developmental factor. Shh provides a morphogenic signal in the developing
CNS, organizing the spatial patterning of cells in the midbrain and inducing proliferation
of neuronal precursor cells in the developing cerebellum, neural tube, and retina.
Proliferative signaling by Shh is involved in the development of cancer, including
specific brain and skin cancers such as basal cell carcinomas. Sonic hedgehog signaling
may proceed by more than one mechanism. One signaling pathway is activated by Shh
binding to Patched (Ptc-1) which releases inhibition of the GPCR Smoothened, activating
the Shh signaling pathway and allowing progression through the G1 phase of the cell
cycle. Shh can also affect progression through the G2/M transition. Patched binds
to phosphorylated Cyclin B1, one component of the M-phase promoting factor (MPF),
along with the kinase Cdc2. The interaction of Cyclin B1 with Patched blocks MPF activity,
blocking progression through the G2/M transition. Shh binding leads to degradation
of Ptc-1, release of Cyclin B1, and entry of the cyclin B1 into the nucleus. Patched
acts as a tumor suppressor by blocking MPF activity. Blockade of the Hedgehog pathway
by cyclopamine demonstrated the therapeutic potential of Hedgehog inhibition in the
treatment of some cancers. (This definition may be outdated - see the DesignNote.);
NCIt note : The BIOCARTA Definition (ALT_DEFINITION) for this pathway concept was provided by
BioCarta. This property was not created by, nor is it maintained by the NCI Thesaurus
staff. Additionally, BioCarta is no longer updating its pathway data; thus, the BIOCARTA
Definition might be outdated or inaccurate. Please see the Terms and Conditions for
Use at http://www.biocarta.com/.;
Biocarta ID : h_ptc1Pathway;
Origin ID : C39203;
UMLS CUI : C1514596;
Semantic type(s)
- has_gene_product_element
- pathway_has_gene_element
