Figure 3 highlights the differentially regulated proteins associated with the significant biological pathways and functions noted above. These include immune response
proteins indicative of an early and sustained up-regulation of proinflammatory, type 1 acute phase protein production (pre-angiotensinogen, serum amyloid A1). We further observed an increase Palbociclib in the abundance of proteins associated with various aspects of immune cell recruitment, adhesion, and/or activation, including candidates functioning in phagocytosis, ubiquitin-mediated proteolysis and class 1 and 2 antigen presentation (leukotriene A4 hydrolase, CD44 antigen, bone marrow stromal cell antigen 2, proteasome beta subunit type 4, major histocompatibility class 1 antigen C (HLA-C), major histocompatibility class 2 antigen DR beta 1, cytochrome b-245 beta). Together, the data show a pattern of increased immune and inflammatory Protein Tyrosine Kinase inhibitor protein abundances observed prior to histologic evidence of significant fibrosis. Patients
with rapidly progressive fibrosis exhibited a decreased abundance of proteins functioning in hepatoprotective responses associated with superoxide, cysteine, glutathione, and xenobiotic metabolism (superoxide dismutase 1, cystathionine beta synthase [CBS], various glutathione S-transferases [GSTs], FK506 binding
protein 14, carboxymethylenebutenolidase homolog) (Fig. 3). These findings suggest that patients with rapidly progressive fibrosis are likely to experience increased oxidative stress. Consistent with this idea, we further observed an increase in the abundance of proteins that function to counteract damaging protein Methisazone and DNA modifications caused by reactive oxidants (aryl sulfotransferase 1A3, thioredoxin reductase 1, alpha thalassemia/mental retardation syndrome X-linked, 5′-3′ exoribonuclease 1) (Fig. 3). Early progression to fibrosis was further associated with the coordinated up- and down-regulation of proteins previously linked to epithelial-to-mesencyhmal transition (family with sequence similarity 3, member C [FAM3C], nexilin, CD44, epithelial cell adhesion molecule), a process recognized as a potential contributor to liver fibrogenesis.24-26 A concomitant up-regulation of cytokines (galectin 3 [LGALS3], insulin-like growth factor binding protein 7 [IGFBP7], angiotensinogen) and cytoskeletal/membrane proteins (tropomyosin 1 [TPM1]; myosin, heavy chain 11 [MYH11]; N-acylsphingosine amidohydrolase 2B) that have been previously associated with the proliferative and contractile phenotype of activated hepatic stellate cells (HSC) was also observed.