Theranostic Imaging of Cancer Gene Therapy

Area of Science:

• Oncology
• Gene Therapy
• Biochemistry

Background:

• Gene-directed enzyme prodrug therapy (GDEPT) offers a targeted approach to cancer treatment, distinct from conventional chemotherapy.
• GDEPT relies on expressing foreign enzymes in cancer cells to convert inert prodrugs into cytotoxic metabolites.
• Theranostic imaging is crucial for monitoring gene expression and therapeutic outcomes in GDEPT.

Purpose of the Study:

• To develop and evaluate a dual-GDEPT system for enhanced cancer gene therapy.
• To combine mutant human herpes simplex thymidine kinase (HSV1sr39TK) and E. coli nitroreductase (NTR) for simultaneous dual-prodrug targeting.
• To establish protocols for in vitro and in vivo imaging of this dual-GDEPT system.

Main Methods:

• Development of a dual-GDEPT system integrating HSV1sr39TK and NTR enzymes.
• Administration of two distinct prodrugs, ganciclovir (GCV) and CB1954, to target different cellular pathways.
• In vitro and in vivo imaging techniques to assess enzyme expression and therapeutic efficacy.

Main Results:

• The dual-GDEPT system demonstrated superior therapeutic efficacy compared to individual GDEPT systems.
• Simultaneous targeting of two cellular mechanisms via two prodrugs at lower doses improved outcomes.
• Successful in vitro and in vivo imaging protocols were established for evaluating the dual-GDEPT system.

Conclusions:

• Dual-GDEPT combining HSV1sr39TK and NTR offers a potent strategy for cancer gene therapy.
• This approach enhances therapeutic efficiency by targeting multiple cancer cell mechanisms simultaneously.
• The developed imaging protocols are essential for the clinical translation and monitoring of GDEPT.