Figure 1.

Schematic depicting approaches utilizing aptamers for immune-oncology applications

(A) A bi-specific aptamer can have dual specificity in which one moiety binds to and activates receptors on tumor-infiltrating T cells (e.g., ICOS or 4-1BB, depicted here as a dimer), whereas the second moiety acts as a tumor-targeting agent (e.g., MRP1) with the intention of limiting co-stimulation to tumor-infiltrating T cells. (B) A tumor cell marker-specific aptamer linked to an siRNA can downregulate the target of interest in a cell-specific manner. The described siRNA can modulate immunogenicity and enhance an anti-tumor immune response. (C) An aptamer specific to tumor-associated myeloid cells is conjugated to a drug (e.g., Dox), whereby the aptamer delivers the drug in a cell-specific manner, reducing toxicity and killing only cells of interest.