HER2 as a Predictive Biomarker and Treatment Target in Colorectal Cancer

Area of Science:

• Oncology
• Molecular Biology
• Genetics

Background:

• Metastatic colorectal cancer (mCRC) has a poor prognosis.
• Anti-epidermal growth factor receptor (EGFR) monoclonal antibodies (mAbs) like cetuximab and panitumumab improve survival in RAS wild-type mCRC.
• However, response to anti-EGFR mAbs is variable, indicating a need for predictive biomarkers.

Purpose of the Study:

• To review the predictive value of human epidermal growth factor receptor 2 (HER2) activation in colorectal cancer (CRC).
• To discuss the potential of HER2 as a therapeutic target in mCRC.
• To highlight the rationale for routine HER2 status testing in CRC.

Main Methods:

• Review of retrospective trials and preliminary studies on HER2 amplification and anti-EGFR mAb resistance.
• Analysis of data on dual HER2 inhibition therapies (trastuzumab plus lapatinib or pertuzumab).
• Synthesis of evidence supporting HER2 as an actionable target in CRC.

Main Results:

• HER2 amplification is suggested as a predictive biomarker for resistance to anti-EGFR mAbs in RAS and RAF wild-type mCRC.
• Dual HER2 inhibition demonstrates promising preliminary anti-tumoral efficacy in RAS wild-type mCRC.
• Evidence supports HER2 as an actionable gene in CRC.

Conclusions:

• HER2 status testing should be considered on a routine basis in metastatic colorectal cancer.
• Targeting HER2 offers a potential strategy to overcome resistance to anti-EGFR therapies.
• Further randomized trials are needed to confirm the efficacy of dual HER2 inhibition.