Background: Cell-free DNA circulating in blood is a candidate biomarker for malignant tumors. Unlike uniformly truncated DNA released from apoptotic nondiseased cells, DNA released from dead cancer cells varies in size. We developed a novel method to measure the ratio of longer to shorter DNA fragments (DNA integrity) in serum as a potential biomarker for patients with colorectal cancer (CRC) or periampullary cancers (PACs). Methods: Sera from 32 patients with CRC (3 stage I, 14 stage II, 6 stage III, and 9 stage IV patients), 19 patients with PACs (2 stage I, 9 stage II, 1 stage III, and 7 stage IV patients), and 51 healthy volunteers were assessed by quantitative real-time PCR of ALU repeats (ALU-qPCR) with 2 sets of primers (115 and 247 bp) amplifying different lengths of DNA. We used serum directly as a template for ALU-qPCR without DNA purification. DNA integrity was determined as ratio of qPCR results of 247-bp ALU over 115-bp ALU. Results: ALU-qPCR had a detection limit of 0.01 pg of DNA. Eliminating DNA purification reduced technical artifacts and reagent/labor costs. Serum DNA integrity was significantly increased for stage I/II and III/IV CRC and stage I/II and III/IV PACs (P ‫؍‬ 0.002, P ‫؍‬ 0.006, P ‫؍‬ 0.022, and P <0.0001, respectively). ROC curves for detecting CRC and PACs had areas under the curves of 0.78 and 0.80, respectively. Conclusions: Direct ALU-qPCR is a robust, highly sensitive, and high-throughput method to measure serum

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There is increasing evidence that food-derived polyphenols have a beneficial effect for cancers. Our purpose was to determine the effect and mechanism of action of these compounds on pancreatic cancer. We measured effects of quercetin on pancreatic cancer in a nude mouse model. We also investigated the effects of quercetin, rutin, trans-resveratrol and genistein on apoptosis and underlying signaling in pancreatic carcinoma cells in vitro. Quercetin decreased primary tumor growth, increased apoptosis and prevented metastasis in a model of pancreatic cancer. In vitro quercetin and transresveratrol, but not rutin, markedly enhanced apoptosis, causing mitochondrial depolarization and cytochrome c release followed by caspase-3 activation. In addition, the effect of a combination of quercetin and trans-resveratrol on mitochondrial cytochrome c release and caspase-3 activity was greater than the expected additive response. The inhibition of mitochondrial permeability transition prevented cytochrome c release, caspase-3 activation and apoptosis caused by polyphenols. Nuclear factor-B activity was inhibited by quercetin and trans-resveratrol, but not genistein, indicating that this transcription factor is not the only mediator of the polyphenols' effects on apoptosis. The results suggest that food-derived polyphenols inhibit pancreatic cancer growth and prevent metastasis by inducing mitochondrial dysfunction, resulting in cytochrome c release, caspase activation and apoptosis.

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The islet in type 2 diabetes mellitus (T2DM) is characterized by a deficit in ␤ cells and islet amyloid derived from islet amyloid polypeptide (IAPP), a protein coexpressed with insulin by ␤ cells. It is increasingly appreciated that the toxic form of amyloidogenic proteins is not amyloid but smaller membrane-permeant oligomers. Using an antibody specific for toxic oligomers and cryo-immunogold labeling in human IAPP transgenic mice, human insulinoma and pancreas from humans with and without T2DM, we sought to establish the abundance and sites of formation of IAPP toxic oligomers. We conclude that IAPP toxic oligomers are formed intracellularly within the secretory pathway in T2DM. Most striking , IAPP toxic oligomers appear to disrupt membranes of the secretory pathway , and then when adjacent to mitochondria , disrupt mitochondrial membranes. Toxic oligomer-induced secretory pathway and mitochondrial membrane disruption is a novel mechanism to account for cellular dysfunction and apoptosis in T2DM. Type 2 diabetes (T2DM) is characterized by a progressive deficit in ␤ cell function and mass with increased ␤ cell apoptosis.1,2 In common with several neurodegenerative diseases such as Alzheimer's disease, Parkinson's disease, and Huntington's disease, the loss of ␤ cells in T2DM is associated with accumulation of locally expressed misfolded proteins that share a propensity to form amyloid.3 Islet amyloid in T2DM is composed primarily of a 37-amino acid protein, islet amyloid polypeptide (IAPP).3 IAPP is co-expressed and secreted with insulin by pancreatic ␤ cells, and is thought to play a paracrine inhibitory role in regulation of insulin secretion. 4,5 The property of IAPP to form amyloid fibrils depends on IAPP 20-29 . This sequence is closely homologous in humans, nonhuman primates and cats, 6 all of which spontaneously develop T2DM characterized by a deficit in ␤ cell mass and islet amyloid. In contrast, rodent IAPP (mouse and rat) does not have the propensity to form amyloid fibrils due to proline substitutions in IAPP 20-29 and wild-type mice and rats do not spontaneously develop T2DM.There is accumulating evidence that the toxic form of amyloidogenic protein aggregates is distinct from amyloid fibrils. The latter tend to accumulate extracellularly where they are relatively inert.3,7 Abnormal non-fibrillar intracellular IAPP aggregates were noted in human insulinoma tissue adjacent to disrupted intracellular membranes.

PURPOSE Differences in cellular levels of histone modifications have predicted clinical outcome in certain cancers. Here, we studied the prognostic and predictive value of three histone modifications in pancreatic adenocarcinoma. METHODS Tissue microarrays (TMAs) from two pancreatic adenocarcinoma cohorts were examined, including those from a 195-patient cohort from Radiation Therapy Oncology Group trial RTOG 9704, a multicenter, phase III, randomized treatment trial comparing adjuvant gemcitabine with fluorouracil and a 140-patient cohort of patients with stage I or II cancer from University of California, Los Angeles Medical Center. Immunohistochemistry was performed for histone H3 lysine 4 dimethylation (H3K4me2), histone H3 lysine 9 dimethylation (H3K9me2), and histone H3 lysine 18 acetylation (H3K18ac). Positive tumor cell staining for each histone modification was used to classify patients into low- and high-staining groups, which were related to clinicopathologic parameters and clinical outcome measures. Results Low cellular levels of H3K4me2, H3K9me2, or H3K18ac were each significant and independent predictors of poor survival in univariate and multivariate models, and combined low levels of H3K4me2 and/or H3K18ac were the most significant predictor of overall survival (hazard ratio, 2.93; 95% CI, 1.78 to 4.82) in the University of California, Los Angeles cohort. In subgroup analyses, histone levels were predictive of survival specifically for those patients with node-negative cancer or for those patients receiving adjuvant fluorouracil, but not gemcitabine, in RTOG 9704. CONCLUSION Cellular levels of histone modifications define previously unrecognized subsets of patients with pancreatic adenocarcinoma with distinct epigenetic phenotypes and clinical outcomes and represent prognostic and predictive biomarkers that could inform clinical decisions, including the use of fluorouracil chemotherapy.

There is epidemiologic evidence that obesity increases the risk of cancers. Several underlying mechanisms, including inflammation and insulin resistance, are proposed. However, the driving mechanisms in pancreatic cancer are poorly understood. The goal of the present study was to develop a model of diet-induced obesity and pancreatic cancer development in a state-of-the-art mouse model, which resembles important clinical features of human obesity, e.g. weight gain and metabolic disturbances. Offspring of Pdx-1-Cre and LSL-KrasG12D mice were allocated to either a diet high in fats and calories (HFCD; ~4,535 kcal/kg; 40% of calories from fats) or control diet (CD; ~3,725 kcal/kg; 12% of calories from fats) for 3 months. Compared to control animals, mice fed the HFCD significantly gained more weight and developed hyperinsulinemia, hyperglycemia, hyperleptinemia, and elevated levels of IGF-1. The pancreas of HFCD-fed animals showed robust signs of inflammation with increased numbers of infiltrating inflammatory cells (macrophages and T-cells), elevated levels of several cytokines and chemokines, increased stromal fibrosis, and more advanced PanIN lesions. Our results demonstrate that a diet high in fats and calories leads to obesity and metabolic disturbances similar to humans and accelerates early pancreatic neoplasia in the conditional KrasG12D mouse model. This model and findings will provide the basis for more robust studies attempting to unravel the mechanisms underlying the cancer-promoting properties of obesity as well as to evaluate dietary- and chemo-preventive strategies targeting obesity-associated pancreatic cancer development.

Epithelial neutrophil-activating peptide-78 (CXCL5), a member of the CXC chemokine family, has been shown to be involved in angiogenesis, tumor growth, and metastasis. The objective of this study was to determine the relationship between CXCL5 expression and tumor progression in human pancreatic cancer and to elucidate the mechanism underlying CXCL5-mediated tumor angiogenesis and cancer growth. We report herein that CXCL5 is overexpressed in human pancreatic cancer compared with paired normal pancreas tissue. Overexpression of CXCL5 is significantly correlated with poorer tumor differentiation, advanced clinical stage, and shorter patient survival. Patients with pancreatic cancer and CXCL5 overexpression who underwent resection of cancer had a mean survival time 25.5 months shorter than that of patients who did not overexpress CXCL5. Blockade of CXCL5 or its receptor CXCR2 by small-interfering RNA knockdown or antibody neutralization attenuated human pancreatic cancer growth in a nude mouse model. Finally, we demonstrated that CXCL5 mediates pancreatic cancer-derived angiogenesis through activation of several signaling pathways, including protein kinase B (Akt), extracellular signal-regulated kinase (ERK), and signal transducer and activator of transcription (STAT) in human endothelial cells. These data suggest that CXCL5 is an important mediator of tumor-derived angiogenesis and that it may serve as a survival factor for pancreatic cancer. Blockade of either CXCL5 or CXCR2 may be a critical adjunct antiangiogenic therapy against pancreatic cancer.