Abstract PO-016: Directed evolution generates novel oncolytic H-1 parvoviruses with improved therapeutic efficacy in virus-resistant pancreatic cancer cells

• Published in: Cancer research (Chicago, Ill.) Ill.), 2021-11, Vol.81 (22_Supplement), p.PO-016-PO-016
• Main Authors: Garcin, Pierre, Kazemimanesh, Monireh, Lulka, Hubert, Dusetti, Nelson, Labrousse, Guillaume, Benuzzi, Emilie, Buscail, Louis, Cordelier, Pierre
• Format: Article
• Language: English
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.PANCA21-PO-016

Despite considerable promise and emerging clinical success, several challenges impede the broader implementation of novel immunotherapies such as oncolytic virus(OV)-based gene therapy, including for patients with pancreatic cancer (PDAC). One of such challenge is inter-patient variability that may impact on OV selectivity and killing efficacy for tumor cells. For this study, we selected the rat parvovirus H-1 (H-1PV) that is nonpathogenic in humans and has a natural oncolytic activity in several cancer models. The safety and tolerability of H-1PV was recently demonstrated in early clinical trials for glioma and PDAC. However, we report here that H-1PV infection, oncolytic and pro-apoptotic activity are limited in PDAC cells, including patient-derived primary cells. To address this concern, we applied a directed evolution strategy to generate H-1PV variants with specific activity towards PDAC cells. Following selection using patient primary cells, we managed to isolate clonal, PDAC-adapted H-1PVs that induce PDAC cells lysis as compared to parental H-1PV while infection of normal pancreatic cells remained negligeable. Genome sequencing of the tumor adapted virus reveals mutations in promoting and viral capsid sequences. In vivo, the tumor-adapted H1PV demonstrates greater anti-tumor effect than parental H-1PV, following intravenous administration in an experimental model of orthotopic pancreatic tumors engrafted in immunodeficient mice. To our knowledge, we report here for the first time the production of highly selective and potent OV using directed evolution to override PDAC resistance to virotherapy. While the molecular mechanisms involved are still under investigation, this project is a first step towards precision medicine strategies based on OV. Citation Format: Pierre Garcin, Monireh Kazemimanesh, Hubert Lulka, Nelson Dusetti, Guillaume Labrousse, Emilie Benuzzi, Louis Buscail, Pierre Cordelier. Directed evolution generates novel oncolytic H-1 parvoviruses with improved therapeutic efficacy in virus-resistant pancreatic cancer cells [abstract]. In: Proceedings of the AACR Virtual Special Conference on Pancreatic Cancer; 2021 Sep 29-30. Philadelphia (PA): AACR; Cancer Res 2021;81(22 Suppl):Abstract nr PO-016.