Assessment of expression of genes encoding the TNF receptor superfamily members as well as the immunoglobulin receptor superfamily revealed upregulation of genes encoding CD28, ICOS, 4-1BB, GITR, OX40, CD27 and CD40 within the NDV-injected tumours, with ICOS being most prominent (Fig. 1h). This evidence concerns the gene TNFRSF9 and neoplasm.