INS and liver cancer: Metformin is one of the oldest and most commonly used drugs in the treatment of type 2 diabetes that reduces blood sugar by decreasing insulin resistance, with no effect on insulin secretion.15 Serious side effects of this drug are rare and mostly due to the simultaneous presence of other diseases in diabetic patients, and not by the drug itself.16 Recently, several studies have shown that metformin may reduce the risk of liver cancer.17-19 Metformin interfere with glucose metabolism that leads to changes in the intracellular pathways.