Anti-patched-1 antibodies suppress hedgehog signaling pathway and pancreatic cancer proliferation.

BACKGROUND The hedgehog (Hh) signaling pathway is aberrantly activated in many human carcinomas including pancreatic cancer and regulates tumor cell growth. Overproduction of sonic hedgehog (Shh), a ligand of the Hh signaling pathway, increases the Hh signaling activity through transmitting the signal to patched-1 (Ptch1), the receptor of the Hh signaling pathway. MATERIALS AND METHODS a-Ptch1 antibodies were raised against an oligo-peptide, designed according to the Ptch1 aminoacid sequence. The specificity of a-Ptch1 was examined by immunoblotting and immuno-fluorescence, and biological effects were detected by RT-PCR and cell proliferation assay using two pancreatic cancer cell lines, Panc1 and SUIT-2. RESULTS a-Ptch1 recognized a 160 kDa protein as shown by immunoblotting and cell surface staining of pancreatic cancer cells. Incubation with a-Ptch1 suppressed Hh signaling activity and proliferation of pancreatic cancer cells. CONCLUSION These results provide a new strategy for controling Hh dependent development of pancreatic cancer and other Hh related carcinomas.