Prospects and progress of oncolytic viruses for treating peripheral nerve sheath tumors

ABSTRACT

Introduction: Peripheral nerve sheath tumors (PNSTs) are an assorted group of neoplasms originating from the neuroectoderm and growing in peripheral nerves. Malignant transformation leads to a poor prognosis and is often lethal. The current treatment of PNSTs is predominantly surgical, which is often incomplete or accompanied by significant loss of function, in conjunction with radiotherapy and/or chemotherapy, for which the benefits are inconclusive. Oncolytic viruses (OVs) efficiently kill tumor cells while remaining safe for normal tissues, and are a novel antitumor therapy for patients with PNSTs.

Areas covered: Because of the low efficacy of current treatments, new therapies for PNSTs are needed. Preclinically, OVs have demonstrated efficacy in treating PNSTs and perineural tumor invasion, as well as safety. We will discuss the various PNSTs and their preclinical models, and the OVs being tested for their treatment, including oncolytic herpes simplex virus (HSV), adenovirus (Ad), and measles virus (MV). OVs can be ‘armed’ to express therapeutic transgenes or combined with other therapeutics to enhance their activity.

Expert opinion: Preclinical testing of OVs in PNST models has demonstrated their therapeutic potential and provided support for clinical translation. Clinical studies with other solid tumors have provided evidence that OVs are safe in patients and efficacious. The recent successful completion of a phase III clinical trial of oncolytic HSV paves the way for oncolytic virotherapy to enter clinical practice.

KEYWORDS:

• Virotherapy
• MPNST
• HSV
• soft-tissue sarcoma