Trastuzumab: triumphs and tribulations

Area of Science:

• Oncology
• Molecular Biology
• Pharmacology

Background:

• HER2 overexpression in 20-30% of breast cancers correlates with poor prognosis.
• Trastuzumab (Herceptin) is a pioneering HER2-targeted monoclonal antibody therapy.
• Trastuzumab demonstrates efficacy in early-stage and metastatic breast cancer but faces primary and acquired resistance.

Purpose of the Study:

• To review the molecular mechanisms of trastuzumab's antineoplastic activity.
• To discuss mechanisms contributing to trastuzumab resistance in HER2-positive breast cancer.
• To explore novel therapeutic agents aimed at enhancing trastuzumab efficacy.

Main Methods:

• Literature review of preclinical and clinical studies on HER2-targeted therapies.
• Analysis of molecular mechanisms underlying trastuzumab action and resistance.
• Discussion of emerging therapeutic strategies and agents.

Main Results:

• Trastuzumab shows response rates of 12-34% in metastatic breast cancer (MBC).
• Significant survival benefits are observed in adjuvant settings for early-stage HER2-overexpressing breast cancer.
• Acquired resistance develops in most MBC patients, and primary resistance occurs in a substantial subset.

Conclusions:

• Understanding trastuzumab's mechanisms and resistance is crucial for improving patient outcomes.
• Novel agents hold promise for overcoming resistance and enhancing HER2-targeted therapy effectiveness.
• Further research into combination therapies is warranted for HER2-positive breast cancer.