GPT and neoplasm: Although the JX-594 and PD-1 inhibitor combination increased the AST and ALT levels compared with the no-tumor-implanted mice at day 21 (P < 0.01 for both AST and ALT levels) (Fig. 5A and 5B), the AST levels did not significantly differ from those in the tumor-implanted mice that received no treatment at day 21 (P = 0.06) (Fig. 5A).