Although most of these oncolytic adenoviruses had not significantly increased the numbers of human CD8+ T cells per gram of tumor tissue, the tumors of all viral treatment groups exhibited significantly higher percentages of granzyme B+ CD8+ T cells in the TILs of their respective day 28 A2058 tumors than vehicle control, indicating that immune mechanisms involving activated CD8+ T cells contributed to the significant reduction in tumor volumes. This evidence concerns the gene CD8A and neoplasm.