TKT and neoplasm: This strategy is a dual-targeted gene therapy regimen, combining (1) Rexin-G, a tumor-targeted retrovector encoding a cytocidal gene to destroy the cancer cells and tumor vasculature and expose tumor neoantigens, and (2) Reximmune-C, a tumor-targeted retrovector encoding a regulatable GM-CSF/Herpes simplex virus Type 1 thymidine kinase (HSV-tk) gene for local paracrine secretion.