Loss of EGFR-ASAP1 signaling in metastatic and unresectable hepatoblastoma

Sci Rep. 2016 Dec 2:6:38347. doi: 10.1038/srep38347.

Abstract

Hepatoblastoma (HBL), the most common childhood liver cancer is cured with surgical resection after chemotherapy or with liver transplantation if local invasion and multifocality preclude resection. However, variable survival rates of 60-80% and debilitating chemotherapy sequelae argue for more informed treatment selection, which is not possible by grading the Wnt-β-catenin over activity present in most HBL tumors. A hypothesis-generating whole transcriptome analysis shows that HBL tumors removed at transplantation are enriched most for cancer signaling pathways which depend predominantly on epidermal growth factor (EGF) signaling, and to a lesser extent, on aberrant Wnt-β-catenin signaling. We therefore evaluated whether EGFR, ASAP1, ERBB2 and ERBB4, which signal downstream after ligation of EGF, and which show aberrant expression in several other invasive cancers, would also predict HBL tumor invasiveness. Immunohistochemistry of HBL tumors (n = 60), which are histologically heterogeneous, shows that compared with well-differentiated fetal cells, less differentiated embryonal and undifferentiated small cells (SCU) progressively lose EGFR and ASAP1 expression. This trend is exaggerated in unresectable, locally invasive or metastatic tumors, in which embryonal tumor cells are EGFR-negative, while SCU cells are EGFR-negative and ASAP1-negative. Loss of EGFR-ASAP1 signaling characterizes undifferentiated and invasive HBL. EGFR-expressing HBL tumors present novel therapeutic targeting opportunities.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adaptor Proteins, Signal Transducing / deficiency*
  • Adaptor Proteins, Signal Transducing / genetics
  • Adolescent
  • Child
  • Child, Preschool
  • Epidermal Growth Factor / genetics
  • Epidermal Growth Factor / metabolism
  • ErbB Receptors / deficiency*
  • ErbB Receptors / genetics
  • Female
  • Gene Expression Regulation, Neoplastic*
  • Hepatoblastoma / genetics*
  • Hepatoblastoma / mortality
  • Hepatoblastoma / secondary
  • Hepatoblastoma / surgery
  • Humans
  • Infant
  • Liver Neoplasms / genetics*
  • Liver Neoplasms / mortality
  • Liver Neoplasms / pathology
  • Liver Neoplasms / surgery
  • Liver Transplantation
  • Lung Neoplasms / genetics*
  • Lung Neoplasms / mortality
  • Lung Neoplasms / secondary
  • Lung Neoplasms / surgery
  • Male
  • Receptor, ErbB-2 / genetics
  • Receptor, ErbB-2 / metabolism
  • Receptor, ErbB-4 / genetics
  • Receptor, ErbB-4 / metabolism
  • Survival Analysis
  • Transcriptome
  • Wnt Signaling Pathway
  • beta Catenin / genetics
  • beta Catenin / metabolism

Substances

  • ASAP1 protein, human
  • Adaptor Proteins, Signal Transducing
  • CTNNB1 protein, human
  • beta Catenin
  • Epidermal Growth Factor
  • EGFR protein, human
  • ERBB2 protein, human
  • ERBB4 protein, human
  • ErbB Receptors
  • Receptor, ErbB-2
  • Receptor, ErbB-4