The extent to which PTP (Protein tyrosine phosphatase) expression may be evident and contribute to the progression to non-alcoholic fatty liver disease (NAFLD)/metabolic dysfunction-associated steatotic liver disease (MASLD) in obesity and the development of hepatocellular carcinoma (HCC) remains unknown. We conducted a comprehensive analysis of the total proteome and PTP expression patterns, using liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of human liver samples. The cohort included liver biopsies obtained from individuals presenting varying degrees of liver disease, encompassing steatosis, Non-alcoholic steatohepatitis (NASH), HCC, and control samples from individuals without evidence of liver damage.