Abstract 3291: Anti-HER2 scFv antibody-directed lentiviral delivery of myrosinase for eradicating HER2+ cancer cells after dosing prodrug sinigrin

Abstract

Abstract Chemotherapy is widely used for the treatment of cancers, but it lacks selectivity and therefore results in collateral damage to healthy cells and drug resistance of cancer cells. Gene-directed enzyme prodrug therapy (GDEPT) has been adopted to mitigate these issues. In this study, we demonstrated the specific targeting of myrosinase-sinigrin paired GDEPT to treat HER2+ (human epidermal growth factor 2) cancer cells. Sinigrin excessively present in cruciferous vegetables can be catalyzed by myrosinase to produce cytotoxic ally isothiocyanate (AITC), which has shown anticancer effectiveness. The myrosinase gene was packed in biotinylated lentiviral vectors produced by co-transfection of HEK293T cells. The single chain variable fragment (scFv) gene sequence of anti-HER2 antibody and core streptavidin (coreSA) gene sequence were cloned in pET-30a(+) plasmid, which was then transformed in Lemo21 (DE3) competent cells for protein expression. The anti-HER2-coreSA chimeric protein was purified using immobilized metal affinity chromatography and characterized by SDS-PAGE and Western blot. The purified chimeric protein was tagged on biotinylated lentivirus via streptavidin-biotin binding. Our results showed that myrosinase-encoding lentivirus tagged with anti-HER2 selectively delivered myrosinase to HER2+ cancer cells. When treated with prodrug sinigrin, the targeted cancer cells underwent apoptosis and ensuing cell death. In summary, the targeted delivery of myrosinase to HER2+ cancer cells using lentivirus functionalized with anti-HER2 ScFv antibody can eradicate malignant cells when treated with enzymatically catalyzed prodrug sinigrin. Citation Format: Ammar Ahmad Tarar, Ching-An Peng. Anti-HER2 scFv antibody-directed lentiviral delivery of myrosinase for eradicating HER2+ cancer cells after dosing prodrug sinigrin [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3291.