Immunology of ovarian and endometrial cancer: from tumor infiltrating lymphocytes to therapy

The immune system plays a crucial role in recognizing and combating tumors. Recent developments in immunotherapy show that we can stimulate the immune system to achieve long-term control over cancer. While CD8+ T cells play a central role in this process, B cells and CD4+ T cells are also important. This thesis investigates the role of these immune cells and the application of immunotherapy in ovarian and endometrial cancer.
Our research shows that ovarian cancer patients with high numbers of CD8+CD103+ T cells, a specialized group of immune cells, generally have better survival rates, especially if they first underwent successful surgery, followed by chemotherapy. We also found that the presence of specific B cells, such as IgA+ B cells, is associated with better survival in ovarian cancer, regardless of the primary treatment. This highlights the importance of tumor-infiltrating B cells as predictors of survival in ovarian cancer.
In endometrial cancer, we similarly observed that IgA+ B cells in tumors are linked to improved survival. Additionally, we found that antibodies produced by these B cells can bind to tumor cell lines, emphasizing their potential as future therapies.
Although immunotherapy for ovarian cancer is still limited, we demonstrated that a vaccine (vididencel) administered after primary treatment can activate the immune system. Further analyses are needed to determine if this also improves survival outcomes. In endometrial cancer, two cycles of immunotherapy before surgery for tumors with many DNA mutations elicited a strong immune response.
In summary, this thesis provides new insights that may contribute to improved treatment strategies in the future.