Immunological response after WT1 mRNA-loaded dendritic cell immunotherapy in ovarian carcinoma and carcinosarcoma.

BACKGROUND

Dendritic cell (DC)-based immunotherapy is an emerging new treatment option in ovarian cancer, an important cause of cancer-related mortality.

PATIENTS AND

METHODS

One patient with ovarian carcinosarcoma (OCS) and one with serous ovarian cancer (SOC) received four weekly vaccinations of autologous DCs electroporated with mRNA coding for the Wilms' tumor gene 1 (WT1). Safety, feasibility and immunogenicity were assessed.

RESULTS

Vaccination was feasible without toxicity. In an ex vivo antigen re-stimulation assay of peripheral blood mononuclear cells, both patients showed increasing cluster of differentiation 137 (CD137+) antigen-specific T-cells and interleukin 10 (IL-10) production post-vaccination. Moreover, interleukin-2 (IL-2) production increased (OCS) as well as interferon-gamma (IFN-γ) and tumor necrosis factor-alpha (TNF-α) (SOC). Disease in patients progressed after four vaccines and patients continued with conventional therapies. After cessation of immunotherapy, they had an extended survival of 19 (OCS) and 12 (SOC) months.

CONCLUSION

To our knowledge, we report for the first time the feasibility and T-cell immunogenicity of WT1 mRNA-loaded DC immunotherapy in ovarian cancer.