Genetically engineered Newcastle disease virus expressing interleukin 2 is a potential drug candidate for cancer immunotherapy.

•rLaSota/IL2 has an antitumor potency but is not a pathogenic for man and poultry.•rLaSota/IL2 enhanced the anti-tumor effects and improved the surveillance of tumor-bearing mice compared with rLasota.•Tumor-specific CTL responses are significantly stimulated after rLaSota/IL2-treated in tumor-bearing mice.•CD4+ and CD8+ T cells proliferation and expression of MHC II are increased after treatment with rLaSota/IL2.