Cancer Vaccine Targeting Mutated GNAQ-Expressing Uveal Melanoma

Area of Science:

• Oncology
• Immunology
• Genetics

Background:

• Uveal melanoma (UM) is the most common adult intraocular malignancy.
• While primary tumor treatment offers high survival, liver metastases are common, suggesting early dormant cell migration.
• Targeting dormant cells via cancer vaccines may prevent metastatic progression.

Purpose of the Study:

• To investigate DNA vaccination for activating immune responses against the common Q209L mutation in GNAQ/GNA11 proteins in UM.
• To assess the potential of cancer vaccines in preventing metastatic disease in UM patients.

Main Methods:

• Developed DNA constructs encoding mutated GNAQ.
• Tested constructs for T cell activation in HLA-A2/Hd transgenic mice and human T cells ex vivo.
• Evaluated vaccine efficacy by measuring T cell responses and cytotoxic activity against UM cells.

Main Results:

• DNA constructs with PADRE and VP22 epitopes enhanced T cell responses against mutant GNAQ.
• These responses correlated with reduced experimental lung metastases.
• Vaccine-activated T cells demonstrated in vitro cytotoxicity against UM cells expressing mutant GNAQ.

Conclusions:

• Fusion DNA vaccines can elicit T cell immunity against UM cells with the Q209L mutation.
• This approach holds promise for preventing the establishment and progression of UM metastatic disease.