Research Breakthrough: Scientists at The University of Texas MD Anderson Cancer Center uncovered key differences in immune environments between primary tumors and metastases that may explain why high-grade serous ovarian carcinoma often suppresses the immune system.
High-grade serous ovarian carcinoma (HGSC) tumors are often able to suppress the immune system to evade being detected and killed.
To better understand how the immune landscape changes over time, researchers examined immune suppression in primary HGSC tumors (still localized to the ovary) versus metastatic HGSC (tumors that have spread) and in untreated versus chemotherapy-treated tumors. They used high-resolution techniques to determine which immune cells are present, how active or “exhausted” they are, and how tumor cells and immune cells communicate.
The team discovered that untreated primary ovarian tumors often contain exhausted immune cells that are less able to fight cancer, and they have strong changes in immune signaling pathways.
Conversely, metastatic tumors and those exposed to treatment show more naïve or memory T cells and fewer exhausted ones.
These findings suggest that primary tumors in untreated patients may respond well to immunotherapy. These differences in the immune microenvironment likely help explain why immune-based therapies have had limited success so far in ovarian cancer, and that choosing treatments based on tumor site (primary vs metastatic) and treatment history could improve outcomes.
Read more:
The dynamic immune behavior of primary and metastatic ovarian carcinoma, published in Nature on April 25, 2025.
Ovarian Cancer Research Alliance (OCRA) Support
- This study was supported by OCRA’s Mentored Investigator Grant.
- OCRA Grantee Co-Authors include Kathleen Moore, MD, MS, University of Oklahoma Health Sciences Center, and a member of OCRA’s Scientific Advisory Committee; Elaine Stur, PhD, MD Anderson Cancer Center, PhD, MD Anderson Cancer Center; Anil Sood, MD Anderson Cancer Center and a member of OCRA’s Scientific Advisory Committee; Ignacio Vázquez-García, Massachusetts General Hospital; and Sohrab Shah, PhD, Memorial Sloan Kettering Cancer Center, a member of OCRA’s Scientific Advisory Committee.
