Hepatocyte expression and prognostic importance of senescence marker p21 in liver histopathology samples from dogs with chronic hepatitis.

Background: Chronic hepatitis (CH) occurs commonly in dogs but is associated with a variable and largely unpredictable prognosis. p21, a cell-cycle inhibitor and marker of cellular senescence, is upregulated in human liver disease and is a better prognostic marker than histological or clinical scoring systems.

Objective: To quantify hepatocyte p21 immunopositivity in histopathology samples from dogs with CH and determine its association with outcome.