IRS1 and malignant peripheral nerve sheath tumor: To investigate the replication and gene expression of IL-12 expressing oncolytic viruses (IL-12 oHSVs), we examined two IL-12 oHSVs, M002 (Δγ134.5, mIL-12) and C002 (Δγ134.5, IRS1, mIL-12), in two representative murine MPNST lines (B109 and 67C-4) based upon our previous studies highlighting oHSV replication and gene expression differences in these MPNST lines (7).