Xanthohumol inhibits the neuroendocrine transcription factor achaete-scute complex-like 1, suppresses proliferation, and induces phosphorylated ERK1/2 in medullary thyroid cancer.
BACKGROUND
Achaete-scute complex-like 1 (ASCL1) is a transcription factor important in the malignant development of medullary thyroid cancer (MTC). Activation of Raf-1 signaling is associated with ASCL1 suppression and growth inhibition. Xanthohumol, a natural compound, has recently been shown to have anticancer properties. We thus hypothesized that xanthohumol would suppress growth by activating Raf-1 signaling, thus altering the malignant phenotype of MTC.


METHODS
Human MTC cells were treated with xanthohumol (0-30 micromol/L) for up to 6 days. Proliferation was measured by a methylthiazolyldiphenyl-tetrazolium bromide (MTT) colorimetric assay. Western blot analysis was performed for ASCL1 and markers of Raf-1 pathway activation.


RESULTS
Treatment of MTC cells with xanthohumol resulted in a dose dependent inhibition of growth. Additionally, induction of phosphorylated ERK1/2 and a reduction of ASCL1 protein was noted.


CONCLUSIONS
Xanthohumol is a potent Raf-1 activator in MTC cells. This compound suppresses MTC growth, alters the malignant phenotype, and warrants further preclinical study.
Endocrine Surgery Research Laboratory, Department of Surgery, University of Wisconsin, Madison, WI, USA.
Mackenzie R
MR
Cook
Jie
J
Luo
Mary
M
Ndiaye
Herbert
H
Chen
Muthusamy
M
Kunnimalaiyaan
D051792:Basic Helix-Loop-Helix Proteins / Q000037:antagonists & inhibitors*; D049109:Cell Proliferation / Q000187:drug effects; D002478:Cells, Cultured; D004354:Drug Screening Assays, Antitumor; D005419:Flavonoids / Q000494:pharmacology*; D006801:Humans; D048052:Mitogen-Activated Protein Kinase 3 / Q000378:metabolism*; D010766:Phosphorylation / Q000187:drug effects; D011427:Propiophenones / Q000494:pharmacology*; D013964:Thyroid Neoplasms / Q000473:pathology*
D051792:Basic Helix-Loop-Helix Proteins; D005419:Flavonoids; D048052:Mitogen-Activated Protein Kinase 3; D011427:Propiophenones; C065500:ASCL1 protein, human; C104536:xanthohumol