Results. Extracellular nucleotide treatment alone was sufficient to induce cell cycle progression in Huh7 cells, evidenced by increased BrdU incorporation and increased cyclin D3, E, and A mRNA and protein expression. We observed
downregulation of cyclin D1 mRNA, however, as previously reported in a subset of HCC with high tumor grade. JNK inhibition attenuated nucleotide-induced cyclin D3, E and A protein expression, MAPK Inhibitor Library concentration but enhanced downregulation of cyclin D1. Mst1/2-/- mouse tumors (at 3–6 months) exhibit dysregulated expression of multiple P2 purinergic receptor isoforms as compared to WT. In HCC patients, multiple P2 purinergic receptor isoforms were elevated >2-fold in liver tumors as compared to uninvolved areas in up to 52% of patients. P2 purinergic receptor upregulation was more prevalent among HCC patients
infected with hepatitis C virus (HCV) (75%) as compared to non-viral groups (20%) identifying a unique subset of viral-induced find more HCC over-expressing P2 receptors. Conclusions. Our results suggest that extracellular nucleotides are potent mitogens in Huh7 cells, inducing downregulation of cyclin D1 and upregulation of cyclin E, which are associated with poor prognosis in HCC patients. Our analysis of HCC patient and Mst1/2-/- mice livers has uncovered a likely role for purinergic signaling in the pathogenesis of HCC, highlighting P2 purinergic receptors as potential biomarkers and novel therapeutic targets for HCC. Disclosures: The following people have nothing to disclose: Janielle P. Maynard, Randy L. Johnson, Dolores Lopez-Terrada, John A. Goss, Sundararajah Thevananther Hepatocellular carcinoma BCKDHB (HCC) is one of the aggressive malignancies mainly due to the recurrence and/or metastasis even after curative resection. There is emerging evidence that tumor metastasis and recurrence might be driven by a small subpop-ulation of stemness cells, so-called cancer stem cells (CSCs). Previous investigations revealed that breast CSCs were found to exhibit intrinsically low proteasome activity, and lower level of reactive oxygen species (ROS).
In this study, two stem cell features, low proteasome activity and low intracellular ROS were visualized in human HCC cells. By use of two-color FACS sorting to isolate the cells with stem cell features, we analyzed the cell division behavior in normoxia and hypoxia, expression of stem cell markers, tumorigenicity, metastatic potential, specific expressing gene signatures and their clinical impact. A visualized small subpopulation of HCC cells demonstrated asymmetric divisions in normoxia, but symmetric divisions in hypoxia. Their remarkable tumorigenicity suggested the cancer initiation potential of the HCC CSCs. Comprehensive gene expression analysis revealed that chemokine-related genes were upregu-lated in the CSCs subpopulation.