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Utilizing Functional Genomics Screening to Identify Potentially Novel Drug Targets in Cancer Cell Spheroid Cultures
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Published on: December 26, 2016

Therapeutically targeting ErbB3: a key node in ligand-induced activation of the ErbB receptor-PI3K axis

Birgit Schoeberl1, Emily A Pace, Jonathan B Fitzgerald

  • 1Merrimack Pharmaceuticals, One Kendall Square, Building 700, Cambridge, MA 02139, USA.

Science Signaling
|July 2, 2009
PubMed

Insights

ErbB3 is a key target in cancer signaling. A new antibody, MM-121, effectively inhibits ErbB3 phosphorylation and tumor growth, offering a novel therapeutic strategy for specific cancers.

Area of Science:

  • Oncology
  • Molecular Biology
  • Computational Biology

Background:

  • The ErbB receptor signaling network is crucial in cancer, but its complexity makes therapeutic targeting challenging.
  • Understanding the relative importance of ErbB network components is vital for effective cancer treatment.
  • Combinatorial, ligand-induced activation of the ErbB-phosphatidylinositol 3-kinase (PI3K) axis presents a therapeutic hurdle.

Purpose of the Study:

  • To computationally model the ErbB signaling network to identify optimal therapeutic inhibition strategies.
  • To explore the role of ErbB3 in response to various ErbB ligands.
  • To introduce and characterize a novel therapeutic agent targeting the ErbB network.

Main Methods:

  • Development of a computational model of the ErbB signaling network.
  • Sensitivity analysis to identify key nodes and ligands.
  • Characterization of a human monoclonal antibody (MM-121) in preclinical cancer models.

Main Results:

  • Sensitivity analysis identified ErbB3 as a critical node in ErbB signaling.
  • MM-121 demonstrated potent inhibition of ErbB3 phosphorylation, distinct from other ErbB therapies.
  • MM-121 halted tumor xenograft growth in mice, validating its therapeutic potential.

Conclusions:

  • ErbB3 is a key therapeutic target in ErbB-driven cancers.
  • MM-121 represents a novel, systems-designed therapeutic for ErbB signaling pathway-related cancers.
  • This approach offers a promising new treatment for patients unresponsive to current therapies.

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