[Development of incurable cancer cell targeted agents using viral technology]

Area of Science:

• Oncolytic virology
• Cancer biology
• Gene therapy

Background:

• Tumor cells in hypoxic environments exhibit resistance to conventional therapies like chemotherapy and radiotherapy.
• Certain cancers, including human sarcoma and malignant mesothelioma, are unresponsive to existing treatments.
• Oncolytic viruses offer a promising strategy for selectively targeting and destroying cancer cells.

Purpose of the Study:

• To engineer novel, multimutated, tumor-specific oncolytic herpes viruses.
• To develop viruses that target the hypoxic tumor microenvironment.
• To evaluate the anti-tumor efficacy of these engineered viruses in preclinical models.

Main Methods:

• Engineering of a herpes virus with a calponin promoter for smooth muscle specificity.
• Incorporation of a fusion protein (HIF1α-ODD/ICP4) to target hypoxic tumor cells.
• In vivo testing in an allogeneic experimental model of undifferentiated pleomorphic sarcoma in Fischer rats.

Main Results:

• The engineered viruses selectively replicated in and disrupted target tumor cells, including sarcoma and mesothelioma.
• Significant anti-tumor effects were confirmed in vivo in a rat sarcoma model.
• The viruses demonstrated efficacy against cancer cells resistant to chemotherapy and targeted therapy.

Conclusions:

• Novel oncolytic herpes viruses targeting tumor-specific promoters and microenvironments are effective against resistant cancers.
• These engineered viruses show significant potential as novel therapeutic agents for challenging malignancies.
• Manufacturing in Good Manufacturing Practice facilities ensures readiness for clinical application.