GPT and neoplasm: Serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) levels were measured with enzyme-linked immunosorbent assay (ELISA) kits, and protein and mRNA expression levels of Ki67 and proliferating cell nuclear antigen (PCNA) in tumor tissues were measured with immunohistochemistry and real-time quantitative polymerase chain reaction (RT-qPCR) techniques.