Non-canonical Hedgehog signaling contributes to chemotaxis in cholangiocarcinoma

Nataliya Razumilava, Sergio A. Gradilone, Rory L. Smoot, Joachim C. Mertens, Steven F. Bronk, Alphonse E. Sirica, Gregory J. Gores

Research output: Contribution to journalArticlepeer-review

44 Scopus citations


Background & Aims The Hedgehog signaling pathway contributes to cholangiocarcinoma biology. However, canonical Hedgehog signaling requires cilia, and cholangiocarcinoma cells often do not express cilia. To resolve this paradox, we examined non-canonical (G-protein coupled, pertussis toxin sensitive) Hedgehog signaling in cholangiocarcinoma cells. Methods Human [non-malignant (H69), malignant (HuCC-T1 and Mz-ChA-1)] and rat [non-malignant (BDE1 and NRC), and malignant (BDEneu)] cell lines were employed for this study. A BDEΔLoop2 cell line with the dominant-negative receptor Patched-1 was generated with the Sleeping Beauty transposon transfection system. Results Cilia expression was readily identified in non-malignant, but not in malignant cholangiocarcinoma cell lines. Although the canonical Hh signaling pathway was markedly attenuated in cholangiocarcinoma cells, they were chemotactic to purmorphamine, a small-molecule direct Smoothened agonist. Purmorphamine also induced remodeling of the actin cytoskeleton with formation of filopodia and lamellipodia-like protrusions. All these biological features of cell migration were pertussis toxin sensitive, a feature of G-protein coupled (Gis) receptors. To further test the role of Hedgehog signaling in vivo, we employed a syngeneic orthotopic rat model of cholangiocarcinoma. In vivo, genetic inhibition of the Hedgehog signaling pathway employing BDE ΔLoop2 cells or pharmacological inhibition with a small-molecule antagonist of Smoothened, vismodegib, was tumor and metastasis suppressive. Conclusions Cholangiocarcinoma cells exhibit non-canonical Hedgehog signaling with chemotaxis despite impaired cilia expression. This non-canonical Hedgehog signaling pathway appears to contribute to cholangiocarcinoma progression, thereby, supporting a role for Hedgehog pathway inhibition in human cholangiocarcinoma.

Original languageEnglish (US)
Pages (from-to)599-605
Number of pages7
JournalJournal of hepatology
Issue number3
StatePublished - Mar 2014


  • Biliary tract cancer
  • Dominant-negative Ptch1
  • G-protein coupled receptor
  • Patched-1
  • Smoothened

ASJC Scopus subject areas

  • Hepatology


Dive into the research topics of 'Non-canonical Hedgehog signaling contributes to chemotaxis in cholangiocarcinoma'. Together they form a unique fingerprint.

Cite this