GPT and hepatocellular carcinoma: The significant reduction in serum ALP, AST and ALT enzymes activity in association with the significant depletion in serum urea and creatinine levels in HCC bearing rats treated with compound 4 (thiazine derivative) go hand in hand with the study of Shabbir et al., (2009) which showed a decreased serum activity of liver enzymes in animals treated with thiazine derivatives.