CTLA4 and neoplasm: VSV∆51-amiR-4 combined with anti-CTLA4 treatment significantly (P value = 0.0013) enhanced tumour regression and prolonged overall survival of mice bearing subcutaneous (SC) B16-F10 melanoma tumours (Supplementary Fig. 7a, b) and was superior to anti-CTLA4 therapy when combined with VSV∆51 that lacks amiR-4.