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Abstract Background Non-alcoholic fatty liver disease is the most common liver disease globally and in its inflammatory form, non-alcoholic steatohepatitis (NASH), can progress to cirrhosis and hepatocellular carcinoma (HCC). Currently, patient education and lifestyle changes are the major tools to prevent the continued progression of NASH. Emerging therapies in NASH target known pathological processes involved in the progression of the disease including inflammation, fibrosis, oxidative stress and hepatocyte apoptosis. Human amniotic epithelial cells (hAECs) were previously shown to be beneficial in experimental models of chronic liver injury, reducing hepatic inflammation and fibrosis. Previous studies have shown that liver progenitor cells (LPCs) response plays a significant role in the development of fibrosis and HCC in mouse models of fatty liver disease. In this study, we examined the effect hAECs have on the LPC response and hepatic oxidative stress in an experimental model of NASH. Methods Experimental NASH was induced in C57BL/6 J male mice using a high-fat, high fructose diet for 42 weeks. Mice received either a single intraperitoneal injection of 2 × 106 hAECs at week 34 or an additional hAEC dose at week 38. Changes to the LPC response and oxidative stress regulators were measured. Results hAEC administration significantly reduced the expansion of LPCs and their mitogens, IL-6, IFNγ and TWEAK. hAEC administration also reduced neutrophil infiltration and myeloperoxidase production with a concurrent increase in heme oxygenase-1 production. These observations were accompanied by a significant increase in total levels of anti-fibrotic IFNβ in mice treated with a single dose of hAECs, which appeared to be independent of c-GAS-STING activation. Conclusions Expansion of liver progenitor cells, hepatic inflammation and oxidative stress associated with experimental NASH were attenuated by hAEC administration. Given that repeated doses did not significantly increase efficacy, future studies assessing the impact of dose escalation and/or timing of dose may provide insights into clinical translation.

Abstract Background Non-alcoholic steatohepatitis (NASH) is among the leading causes of liver disease worldwide. It is increasingly recognized that the phenotype of NASH may involve a number of different pathways, of which each could become important therapeutic targets. The aim of this study is to use high resolution mass spectrometry (MS) and phosphoproteomics techniques to assess the serum proteome and hepatic phosphoproteome in subjects with NASH-related fibrosis. Methods Sixty-seven biopsy-proven NAFLD subjects with frozen sera and liver tissue were included. Reverse phase protein microarray was used to quantify the phosphorylation of key signaling proteins in liver and nano-liquid chromatography (LC)-MS was used to sequence target biomarkers in the serum. An image analysis algorithm was used to quantify the percentage of collagen (% collagen) using computer-assisted morphometry. Using multiple regression models, serum proteomes and phosphorylated hepatic proteins that were independently (p ≤ 0.05) associated with advanced fibrosis (stage ≥ 2) and higher % collagen were assessed. Results Phosphorylated signaling pathways in the liver revealed that apoptosis signal-regulating kinase 1, mitogen-activated protein kinase (ASK1-MAPK pathway involving ASK1 S38 (p

Abstract Endocrine therapy (ET) in combination with CDK4/6 inhibition is routinely used as first-line treatment for HR+/HER2− metastatic breast cancer (MBC) patients. However, 30–40% of patients quickly develop disease progression. In this open-label multicenter clinical trial, we utilized a hypothesis-driven protein/phosphoprotein-based approach to identify predictive markers of response to ET plus CDK4/6 inhibition in pre-treatment tissue biopsies. Pathway-centered signaling profiles were generated from microdissected tumor epithelia and surrounding stroma/immune cells using the reverse phase protein microarray. Phosphorylation levels of the CDK4/6 downstream substrates Rb (S780) and FoxM1 (T600) were higher in patients with progressive disease (PD) compared to responders (p = 0.02). Systemic PI3K/AKT/mTOR activation in tumor epithelia and stroma/immune cells was detected in patients with PD. This activation was not explained by underpinning genomic alterations alone. As the number of FDA-approved targeted compounds increases, functional protein-based signaling analyses may become a critical component of response prediction and treatment selection for MBC patients.

[This corrects the article DOI: 10.1371/journal.pone.0191983.].

Rift Valley fever virus (RVFV) infects both ruminants and humans leading to a wide variance of pathologies dependent on host background and age. Utilizing a targeted reverse phase protein array (RPPA) to define changes in signaling cascades after in vitro infection of human cells with virulent and attenuated RVFV strains, we observed high phosphorylation of Smad transcription factors. This evolutionarily conserved family is phosphorylated by and transduces the activation of TGF-β superfamily receptors. Moreover, we observed that phosphorylation of Smad proteins required active RVFV replication and loss of NSs impaired this activation, further corroborating the RPPA results. Gene promoter analysis of transcripts altered after RVFV infection identified 913 genes that contained a Smad-response element. Functional annotation of these potential Smad-regulated genes clustered in axonal guidance, hepatic fibrosis and cell signaling pathways involved in cellular adhesion/migration, calcium influx, and cytoskeletal reorganization. Furthermore, chromatin immunoprecipitation confirmed the presence of a Smad complex on the interleukin 1 receptor type 2 (IL1R2) promoter, which acts as a decoy receptor for IL-1 activation.