Linking HER2 Expression, Genomic Features, and Immune Microenvironment Changes in EOC

Overview

This study investigates the genomic and immunogenic characteristics associated with HER2-expressing epithelial ovarian cancer (EOC). It highlights the differences in tumor features and immune microenvironment between HER2 high and low tumors.

Background

Epithelial ovarian cancer (EOC) remains a leading cause of cancer-related mortality among women, with limited improvements in survival rates despite advances in treatment. The introduction of HER2-targeted therapies, such as trastuzumab deruxtecan (T-DXd), has shown promise.

Data Highlights

No significant differences were detected in HRD, CCNE1 amplification, and ARID1A status between HER2 high and low tumors. Patients with HER2 high tumors exhibited lower FOLR1 positivity and higher PD-L1 positivity. Intratumoral PD-L1 expression and CD4+ T cell levels were significantly higher in HER2 high tumors. T-DXd treatment downregulated PD-L1 and VEGFA expression.

Key Findings

• Non-significant differences in HRD, CCNE1 amplification, and ARID1A status between HER2 high and low tumors.
• HER2 high tumors had lower FOLR1 positivity and higher PD-L1 positivity.
• Intratumoral PD-L1 expression and CD4+ T cell levels were significantly higher in HER2 high tumors (p<0.05).
• T-DXd treatment substantially downregulated PD-L1 and VEGFA expression.
• Combination treatment with T-DXd and bevacizumab synergistically reduced VEGF expression.

Clinical Implications

Further exploration of combinatorial treatment strategies involving T-DXd may be warranted.

Conclusion

This study provides insights into the genomic and immune characteristics of HER2-expressing EOC.

Related Resources & Content

1. Frontiers in Immunology, 2026 -- Follicular T cells in the ovarian cancer immune microenvironment: biological insights and translational implications
2. Frontiers in Oncology, 2026 -- Understanding the immune microenvironment of ovarian cancer
3. The ASCO Post, 2013 -- Role of Epithelial-to-Mesenchymal Transition in Ovarian Cancer
4. FDA -- FDA grants accelerated approval to fam-trastuzumab deruxtecan-nxki for unresectable or metastatic HER2-positive solid tumors
5. ESMO Clinical Practice Guideline Express Update on the management of epithelial ovarian cancer - PMC
6. The ASCO Post — Understanding the Role of Immune Function in the Treatment of HER2-Positive Breast Cancer
7. ESMO Clinical Practice Guideline Express Update on the management of epithelial ovarian cancer - PMC
8. FDA grants accelerated approval to fam-trastuzumab deruxtecan-nxki for unresectable or metastatic HER2-positive solid tumors | FDA
9. Human epidermal growth factor receptor-2 expression and subsequent dynamic changes in patients with ovarian cancer - PubMed