Related Experiment Video
Updated: Jun 19, 2025
Paramyxoviruses for Tumor-targeted Immunomodulation: Design and Evaluation Ex Vivo
Published on: January 7, 2019
Simultaneous Expression of Different Therapeutic Genes by Infection with Multiple Oncolytic HSV-1 Vectors
Adriana Vitiello1, Alberto Reale1, Valeria Conciatori1
1Department of Molecular Medicine, University of Padua, 35121 Padua, Italy.
Abstract:
Oncolytic viruses (OVs) are anti-cancer therapeutics combining the selective killing of cancer cells with the triggering of an anti-tumoral immune response. The latter effect can be improved by arming OVs with immunomodulatory factors. Due to the heterogeneity of cancer and the tumor microenvironment, it is anticipated that strategies based on the co-expression of multiple therapeutic molecules that interfere with different features of the target malignancy will be more effective than mono-therapies. Here, we show that (i) the simultaneous expression of different proteins in triple-negative breast cancer (TNBC) cells can be achieved through their infection with a combination of OVs based on herpes simplex virus type 1 (oHSV1), each encoding a single transgene. (ii) The level of expressed proteins is dependent on the number of infectious viral particles utilized to challenge tumor cells. (iii) All recombinant viruses exhibited comparable efficacy in the killing of TNBC cells in single and multiple infections and showed similar kinetics of replication. Overall, our results suggest that a strategy based on co-infection with a panel of oHSV1s may represent a promising combinatorial therapeutic approach for TNBC, as well as for other types of solid tumors, that merits further investigation in more advanced in vitro and in vivo models.
Insights
Oncolytic viruses (OVs) engineered to express multiple therapeutic proteins show promise for treating triple-negative breast cancer (TNBC). Co-infection with a panel of these modified herpes simplex viruses (oHSV1) effectively kills cancer cells and warrants further study.
Area of Science:
- Oncolytic virology
- Cancer immunotherapy
- Gene therapy
Background:
- Oncolytic viruses (OVs) are engineered viruses that selectively infect and kill cancer cells while stimulating an anti-tumor immune response.
- Enhancing OV efficacy often involves arming them with immunomodulatory factors to improve anti-tumor immunity.
- Cancer's complexity necessitates combinatorial strategies, potentially involving co-expression of multiple therapeutic molecules for greater effectiveness than monotherapies.
Purpose of the Study:
- To investigate the feasibility of simultaneously expressing multiple therapeutic proteins in triple-negative breast cancer (TNBC) cells using a combination of oncolytic herpes simplex virus type 1 (oHSV1) vectors.
- To assess the impact of viral particle dosage on protein expression levels.
- To evaluate the efficacy and replication kinetics of recombinant oHSV1s in both single and multiple infection settings for TNBC treatment.
Main Methods:
- Generation of recombinant oHSV1s, each encoding a single transgene.
- Co-infection of TNBC cells with a panel of these oHSV1 vectors.
- Quantification of protein expression levels based on viral particle input.
- Assessment of viral replication kinetics and cancer cell killing efficacy in vitro.
Main Results:
- Simultaneous expression of different proteins in TNBC cells was successfully achieved through co-infection with multiple oHSV1 vectors.
- Protein expression levels were directly correlated with the multiplicity of infection (number of viral particles used).
- All recombinant oHSV1s demonstrated comparable efficacy in killing TNBC cells and exhibited similar replication kinetics, regardless of single or multiple infections.
Conclusions:
- A combinatorial strategy utilizing co-infection with a panel of oHSV1s represents a promising therapeutic approach for TNBC.
- This multi-targeting strategy holds potential for treating other solid tumors and warrants further investigation in advanced preclinical models.
- The ability to achieve dose-dependent, simultaneous expression of multiple therapeutic agents via oHSV1 co-infection offers a flexible platform for combinatorial cancer therapy.
