GPT and neoplasm: Four months after subcutaneous injection in nude mice, the serum level of ALT and AST of xenografts were slightly increased compared to control (102 ± 23 IU vs. 77 ± 9 IU for ALT and 23 ± 2 IU vs. 17 ± 1 IU for AST) even though no tumor nodules were observed.