Physiological function of polyploid hepatocytes and pathological changes in its associated diseases

Abstract

Liver is a unique organ with polyploidy. About 20 to 50 percent of hepatocytes in adult human are polyploid cells, which contain more than two sets of chromosomes. Hepatocytes polyploidization is triggered by the changes in insulin signal during weaning, and regulated by various cell cycle regulator genes to ensure the polyploid cells proportion, ploidy and zonation. The regulation of polyploid hepatocytes is crucial for liver's metabolic and regenerative function, and protecting liver from tumorigenesis. However, in chronic virus hepatitis and nonalcoholic fatty liver disease, the pathological hepatocytes polyploidization can be found in disease progression because of cell cycle checkpoint inhibition and oxidative stress. Distinguishing physiological and pathological hepatocyte polyploidization will be helpful for the understanding the relationship between chronic liver disease and tumorigenesis.

Keywords

• |ploidy|polyploidy|chromosomal instability|hepatocyte|hepatocellular carcinoma