Dual-vector prodrug activator gene therapy using retroviral replicating vectors

Area of Science:

• Oncolytic virology
• Gene therapy
• Hepatocellular carcinoma research

Background:

• Retroviral replicating vectors (RRVs) show promise for efficient tumor transduction and enhanced therapeutic benefits in cancer models.
• Investigating combinatorial gene therapy approaches can potentially improve treatment efficacy.

Purpose of the Study:

• To evaluate the combinatorial effect of prodrug activator genes delivered by two distinct RRVs (AMLV and GALV) on human hepatocellular carcinoma Hep3B cells.
• To assess the synergistic cytotoxic effects of dual-vector gene therapy using yeast cytosine deaminase (CD) and herpes simplex virus thymidine kinase (TK) genes.

Main Methods:

• Utilized two distinct RRVs derived from amphotropic murine leukemia virus (AMLV) and gibbon ape leukemia virus (GALV).
• Transduced Hep3B cells with RRVs encoding CD and/or TK genes.
• Administered prodrugs 5-fluorocytosine and ganciclovir to evaluate cytotoxic effects.

Main Results:

• Both RRVs exhibited efficient replicative spread and overcame superinfection resistance.
• Replication and spread of each RRV were unaffected by pretransduction with the counterpart RRV.
• Combined delivery of CD and TK genes via two different RRVs resulted in significantly greater synergistic cytocidal effects compared to single-vector delivery.

Conclusions:

• Dual-vector gene therapy using two distinct RRVs carrying different prodrug activator genes demonstrates significant synergistic anticancer effects.
• This approach holds potential utility for enhancing hepatocellular carcinoma treatment strategies.