TASK DEFINITION: Given a passage classify if the passage has a definite objective/aim/goal or not. Output '1' if the passage has a defininte objective/aim/goal and output '0' if the passage does not have a definite objective/aim/goal.
PROBLEM: Human hepatocellular carcinoma (HCC) heterogeneity promotes recurrence and resistance to therapies. Recent studies have reported that HCC may be derived not only from adult hepatocytes and hepatoblasts but also hepatic stem/progenitors. In this context, HepaRG cells may represent a suitable cellular model to study stem/progenitor cancer cells and the retrodifferentiation of tumor-derived hepatocyte-like cells. Indeed, they differentiate into hepatocyte- and biliary-like cells. Moreover, tumor-derived HepaRG hepatocyte-like cells (HepaRG-tdHep) differentiate into both hepatocyte- and biliary-like cells through a hepatic progenitor. In this study we report the mechanisms and molecular effectors involved in the retrodifferentiation of HepaRG-tdHep into bipotent progenitors. Gene expression profiling was used to identify genomic changes during the retrodifferentiation of HepaRG-tdHep into progenitors. We demonstrated that gene expression signatures related to a poor-prognosis HCC subclass, proliferative progenitors, or embryonic stem cells were significantly enriched in HepaRG progenitors derived from HepaRG-tdHep. HepaRG-tdHep retrodifferentiation is mediated by crosstalk between transforming growth factor beta 1 (TGFβ1) and inflammatory cytokine pathways (e.g., tumor necrosis factor alpha [TNFα] and interleukin 6 [IL6]). Signatures related to TNFα, IL6, and TGFβ activation pathways are induced within the first hour of retrodifferentiation. Moreover, specific activation or inhibition of these signaling pathways allowed us to determine that TNFα and IL6 contribute to the loss of hepatic-specific marker expression and that TGFβ1 induces an epithelial-to-mesenchymal transition of HepaRG-tdHep. Interestingly, the retrodifferentiation process is blocked by the histone deacetylase inhibitor trichostatin A, opening new therapeutic opportunities.

SOLUTION: 0

PROBLEM: Multiple diverse posttranslational modifications of alpha-tubulin such as detyrosination, further cleavage of the penultimate glutamate residue (Delta2-tubulin), acetylation, and polyglutamylation increase the structural and functional diversity of microtubules.', 'Herein, we characterized the molecular profile of alpha-tubulin posttranslational modifications in normal human prostate epithelial cells (PrEC), immortalized normal prostate epithelial cells (PZ-HPV-7), androgen-dependent prostate cancer cells (LNCaP), transitional androgen-independent prostate cancer cells (LNCaP-cds and CWR22Rv1), and androgen-independent prostate cancer cells (PC3).', 'Compared to PrEC and PZ-HPV-7 cells, all cancer cells exhibited elevated levels of detyrosinated and polyglutamylated alpha-tubulin, that was paralleled by decreased protein levels of tubulin tyrosine ligase (TTL). In contrast, PrEC and PZ-HPV-7 cells expressed markedly higher levels of Delta2-tubulin. Whereas alpha-tubulin acetylation levels were generally equivalent in all the cell lines, PC3 cells did not display detectable levels of Ac-tubulin.

SOLUTION: 0

PROBLEM: Interleukin (IL)-33 is a recently identified member of the IL-1 family that binds to the receptor, ST2L. In the current study, we sought to determine whether IL-33 is an important regulator in the hepatic response to ischemia/reperfusion (I/R). Male C57BL/6 mice were subjected to 90 minutes of partial hepatic ischemia, followed by up to 8 hours of reperfusion. Some mice received recombinant IL-33 (IL-33) intraperitoneally (IP) before surgery or anti-ST2 antibody IP at the time of reperfusion. Primary hepatocytes and Kupffer cells were isolated and treated with IL-33 to assess the effects of IL-33 on inflammatory cytokine production. Primary hepatocytes were treated with IL-33 to assess the effects of IL-33 on mediators of cell survival in hepatocytes. IL-33 protein expression increased within 4 hours after reperfusion and remained elevated for up to 8 hours. ST2L protein expression was detected in healthy liver and was up-regulated within 1 hour and peaked at 4 hours after I/R. ST2L was primarily expressed by hepatocytes, with little to no expression by Kupffer cells. IL-33 significantly reduced hepatocellular injury and liver neutrophil accumulation at 1 and 8 hours after reperfusion. In addition, IL-33 treatment increased liver activation of nuclear factor kappa light-chain enhancer of activated B cells (NF-κB), p38 mitogen-activated protein kinase (MAPK), cyclin D1, and B-cell lymphoma 2 (Bcl-2), but reduced serum levels of CXC chemokines. In vitro experiments demonstrated that IL-33 significantly reduced hepatocyte cell death as a result of increased NF-κB activation and Bcl-2 expression in hepatocytes.

SOLUTION:
0