Pancreatic cancer is a highly lethal disease with a poor prognosis, and existing therapies offer only limited effectiveness. Mutation gene sequencing has shown several gene associations that may account for its carcinogenesis, revealing a promising research direction. Poly (ADP-ribose) polymerase (PARP) inhibitors target tumor cells with a homologous recombination repair (HRR) deficiency based on the concept of synthetic lethality. The most prominent target gene is BRCA, in which mutations were first identified in breast cancer and ovarian cancer. PARP inhibitors can trap the PARP-1 protein at a single-stranded break/DNA lesion and disrupt its catalytic cycle, ultimately leading to replication fork progression and consequent double-strand breaks. For tumor cells with BRCA mutations, HRR loss would result in cell death. Pancreatic cancer has also been reported to have a strong relationship with BRCA gene mutations, which indicates that pancreatic cancer patients may benefit from PARP inhibitors. Several clinical trials are being conducted and have begun to yield results. For example, the POLO (Pancreatic Cancer Olaparib Ongoing) trial has demonstrated that the median progression-free survival was observably longer in the olaparib group than in the placebo group. However, PARP inhibitor resistance has partially precluded their use in clinical applications, and the major mechanism underlying this resistance is the restoration of HRR. Therefore, determining how to use PARP inhibitors in more clinical applications and how to avoid adverse effects, as well as prognosis and treatment response biomarkers, require additional research. This review elaborates on future prospects for the application of PARP inhibitors in pancreatic cancer.

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analysis reveals diabetic kidney as a ketogenic organ in type 2 diabetes. Am J Physiol Endocrinol Metab 300: E287-E295, 2011. First published October 19, 2010 doi:10.1152/ajpendo.00308.2010 is the leading cause of end-stage renal disease. To date, the molecular mechanisms of DN remain largely unclear. The present study aimed to identify and characterize novel proteins involved in the development of DN by a proteomic approach. Proteomic analysis revealed that 3-hydroxy-3-methylglutaryl-CoA (HMG-CoA) synthase 2 (HMGCS2), the key enzyme in ketogenesis, was increased fourfold in the kidneys of type 2 diabetic db/db mice. Consistently, the activity of HMGCS2 in kidneys and 24-h urinary excretion of the ketone body ␤-hydroxybutyrate (␤-HB) were significantly increased in db/db mice. Immunohistochemistry, immunofluorescence, and real-time PCR studies further demonstrated that HMGCS2 was highly expressed in renal glomeruli of db/db mice, with weak expression in the kidneys of control mice. Because filtered ketone bodies are mainly reabsorbed in the proximal tubules, we used RPTC cells, a rat proximal tubule cell line, to examine the effect of the increased level of ketone bodies. Treating cultured RPTC cells with 1 mM ␤-HB significantly induced transforming growth factor-␤1 expression, with a marked increase in collagen I expression. ␤-HB treatment also resulted in a marked increase in vimentin protein expression and a significant reduction in E-cadherin protein levels, suggesting an enhanced epithelial-to-mesenchymal transition in RPTCs. Collectively, these findings demonstrate that diabetic kidneys exhibit excess ketogenic activity resulting from increased HMGCS2 expression. Enhanced ketone body production in the diabetic kidney may represent a novel mechanism involved in the pathogenesis of DN.

Alanine aminotransferase (ALT) is the most commonly used marker of liver injury, but normal ALT levels are seen in a proportion of chronic hepatitis B virus (HBV)-infected patients with severe liver injury. Golgi protein 73 (GP73) is a promising alternative marker of liver injury. This study assessed the relation between GP73 levels and liver disease severity, monitored the kinetic changes in GP73 levels in chronic HBV patients receiving entecavir (ETV) therapy, and investigated the potential diagnostic and prognostic values of serum GP73 as a new liver injury biomarker in chronic HBV infections.This study enrolled 1150 patients with chronic HBV infections, 200 of whom were retrospectively enrolled in this study after receiving 1 year of ETV treatment. GP73 expression in liver tissue was detected by immunohistochemistry. GP73 levels in single or serial serum samples were measured by enzyme-linked immunosorbent assay.Immunohistochemical analysis indicated that GP73 protein expression in the liver increased progressively with pathologic progression from nonexistent or mild hepatitis to severe hepatitis and cirrhosis during chronic HBV infection. Serum GP73 levels were positively correlated with the disease severity of chronic HBV infections (r = 0.58, P < 0.001). In patients with normal ALT levels, serum GP73 concentrations were significantly higher in patients with prominent hepatic inflammatory injury and fibrosis than in patients without hepatic inflammatory injury or fibrosis. Serum GP73 concentrations and GP73 protein expression were decreased in the liver tissues of patients whose ALT levels normalized after 1 year of ETV antiviral therapy.Changes in serum GP73 levels were closely associated with changes in liver injury severity, and, therefore, GP73 may be an effective new liver inflammatory injury biomarker, and could be useful for monitoring the prognosis of chronic HBV infectious patients with normal ALT levels.