Wnt signaling and hepatocarcinogenesis: the hepatoblastoma model.
The Wnt/β-catenin pathway plays a key role in liver development, regeneration and tumorigenesis. Among human cancers tightly linked to abnormal Wnt/β-catenin signaling, hepatoblastoma (HB) presents with the highest rate (50-90%) of β-catenin mutations. HB is the most common malignant tumor of the liver in childhood. This embryonic tumor differs from hepatocellular carcinoma by the absence of viral etiology and underlying liver disease, and by distinctive morphological patterns evoking hepatoblasts, the bipotent precursors of hepatocytes and cholangiocytes. Recent studies of the molecular pathogenesis of hepatoblastoma have led to identify two major tumor subclasses resembling early and late phases of prenatal liver development and presenting distinctive chromosomal alterations. It has been shown that the molecular signature of Wnt/β-catenin signaling in hepatoblastoma is mainly imposed by liver context, but differs according to developmental stage. Finally, the differentiation stage of tumor cells strongly influences their invasive and metastatic properties, therefore affecting clinical behavior.
Armengol
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Oncogenesis and Molecular Virology Unit, Institut Pasteur, Inserm U579, Paris, France.
Cairo
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Fabre
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Buendia
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MA
D000818:Animals; D002454:Cell Differentiation; D018197:Hepatoblastoma / Q000378:metabolism* / Q000473:pathology; D022781:Hepatocytes / Q000473:pathology; D006801:Humans; D008113:Liver Neoplasms / Q000378:metabolism* / Q000473:pathology; D051379:Mice; D018345:Mice, Knockout; D009154:Mutation; D015398:Signal Transduction; D051153:Wnt Proteins / Q000502:physiology*; D051176:beta Catenin / Q000235:genetics / Q000502:physiology
D051153:Wnt Proteins; D051176:beta Catenin