A Mouse to Human Search for Plasma Proteome Changes Associated with Pancreatic Tumor Development

Background: The complexity and heterogeneity of the human plasma proteome have presented significant challenges in the identification of protein changes associated with tumor development. Refined genetically engineered mouse (GEM) models of human cancer have been shown to faithfully recapitulate the molecular, biological, and clinical features of human disease. Here, we sought to exploit the merits of a well-characterized GEM model of pancreatic cancer to determine whether proteomics technologies allow identification of protein changes associated with tumor development and whether such changes are relevant to human pancreatic cancer. Methods and Findings: Plasma was sampled from mice at early and advanced stages of tumor development and from matched controls. Using a proteomic approach based on extensive protein fractionation, we confidently identified 1,442 proteins that were distributed across seven orders of magnitude of abundance in plasma. Analysis of proteins chosen on the basis of increased levels in plasma from tumor-bearing mice and corroborating protein or RNA expression in tissue documented concordance in the blood from 30 newly diagnosed patients with pancreatic cancer relative to 30 control specimens. A panel of five proteins selected on the basis of their increased level at an early stage of tumor development in the mouse was tested in a blinded study in 26 humans from the CARET (Carotene and Retinol Efficacy Trial) cohort. The panel discriminated pancreatic cancer cases from matched controls in blood specimens obtained between 7 and 13 mo prior to the development of symptoms and clinical diagnosis of pancreatic cancer. Conclusions: Our findings indicate that GEM models of cancer, in combination with in-depth proteomic analysis, provide a useful strategy to identify candidate markers applicable to human cancer with potential utility for early detection

Early Detection of Hepatocellular Carcinoma: How to Screen and Follow up Patients with Liver Cirrhosis According to the GERMAN S3 Guideline?

Hepatocellular carcinoma (HCC) is frequently detected in pre-existing liver cirrhosis, but can also develop without such pre-conditions. There is an increasing trend of HCC incidence worldwide. In patients with liver cirrhosis, HCC has become the leading cause of death. At diagnosis the tumor has very often reached an advanced stage and curative treatment options are missing. Thus, early diagnosis would help the patient and prevent increasing healthcare costs. In our review we will summarize the recommendations of the German S3 guideline for the early diagnosis of HCC and will discuss the current literature in this context. The reader will learn which diagnostic tools are available and in what order they can be usefully applied. Surveillance should be done with ultrasound by a skilled examiner, additional imaging at best with state-of-the-art dynamic magnetic resonance

Correction: Activation of Notch Signaling Is Required for Cholangiocarcinoma Progression and Is Enhanced by Inactivation of p53 In Vivo.

[This corrects the article DOI: 10.1371/journal.pone.0077433.]

Epithelial mesenchymal transition and pancreatic tumor initiating CD44+/EpCAM+ cells are inhibited by γ-secretase inhibitor IX.

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive disease with a high rate of metastasis. Recent studies have indicated that the Notch signalling pathway is important in PDAC initiation and maintenance, although the specific cell biological roles of the pathway remain to be established. Here we sought to examine this question in established pancreatic cancer cell lines using the γ-secretase inhibitor IX (GSI IX) to inactivate Notch. Based on the known roles of Notch in development and stem cell biology, we focused on effects on epithelial mesenchymal transition (EMT) and on pancreatic tumor initiating CD44+/EpCAM+ cells. We analyzed the effect of the GSI IX on growth and epithelial plasticity of human pancreatic cancer cell lines, and on the tumorigenicity of pancreatic tumor initiating CD44+/EpCAM+ cells. Notably, apoptosis was induced after GSI IX treatment and EMT markers were selectively targeted. Furthermore, under GSI IX treatment, decline in the growth of pancreatic tumor initiating CD44+/EpCAM+ cells was observed in vitro and in a xenograft mouse model. This study demonstrates a central role of Notch signalling pathway in pancreatic cancer pathogenesis and identifies an effective approach to inhibit selectively EMT and suppress tumorigenesis by eliminating pancreatic tumor initiating CD44+/EpCAM+ cells

Activation of Notch Signaling Is Required for Cholangiocarcinoma Progression and Is Enhanced by Inactivation of p53 <i>In Vivo</i>

<div><p>Cholangiocacinoma (CC) is a cancer disease with rising incidence. Notch signaling has been shown to be deregulated in many cancers. However, the role of this signaling pathway in the carcinogenesis of CC is still not fully explored. In this study, we investigated the effects of Notch inhibition by γ-secretase inhibitor IX (GSI IX) in cultured human CC cell lines and we established a transgenic mouse model with liver specific expression of the intracellular domain of Notch (Notch-ICD) and inactivation of tumor suppressor p53. GSI IX treatment effectively impaired cell proliferation, migration, invasion, epithelial to mesenchymal transition and growth of softagar colonies. <i>In vivo</i> overexpression of Notch-ICD together with an inactivation of p53 significantly increased tumor burden and showed CC characteristics. <i>Conclusion</i>: Our study highlights the importance of Notch signaling in the tumorigenesis of CC and demonstrates that additional inactivation of p53 <i>in vivo</i>.</p></div

Notch plays a pivotal role for the regulation of migration in human cholangiocarcinoma cells.

<p>Treatment with GSI IX suppresses the migration potential of human cholangiocarcinoma cell lines SZ1 and TFK1. Wound healing experiments of (A) SZ1 and (C) TFK cells cultured with GSI (5 µM, 20 µM, 40 µM) or control (DMSO). A scratch was made at (time 0 h) in both SZ1 and TFK1 and maintained for 24 h in conditioned medium with GSI or DMSO. The dotted lines are representing the edges of the wound. Photographs were taken under light microscope (10X magnification). After 24 h (A) SZ1 showed significant inhibition under 5–40 µM GSI and (C) TFK1 with a dose of 20–40 µM GSI treatment. In DMSO treated cells 80% to 90% of the wound healing was observed after 24 hrs. (A,C) The migration index (B,D) was calculated as described in Material and Methods and plotted in bar graphs. P values were calculated with ANOVA analysis of variance along with Bonferroni post test. The error bar represents standard deviation. Differences were considered as statistically significant (*) when the P-value was less <0.05.</p

Summary of observation in NotchICD :: AlbCre :: p53 L/L mice.

<p>Summary of observation in NotchICD :: AlbCre :: p53 L/L mice.</p

NICD overexpression and loss of p53 is influencing the tumor development of cholangiocarcinomas in mice.

<p>Macro- und microscopic pictures of mice with expression of AlbCre and Notch-ICD and inactivation of p53 at different timepoints like indicated. Each mouse was dissected at the indicated timepoint. H&E staining (20X magnification) was performed and analysis was accordingly done in collaboration with an independent pathologist. Note, there was no tumor either macroscopically or microscopically detected with an age of 3 month. Starting with an age of 6 month, mice with expression of AlbCre, Notch-ICD and loss of p53 developed cholangiocarcinomas.</p

GSI IX attenuate invasion of human cholangiocarcinoma cells.

<p>SZ1 (A) and TFK1 (A) cell lines were treated for 48 h with control (DMSO) and GSI (5 µM, 20 µM, 40 µM) to investigate the effect of GSI on invasiveness of human cholangiocarcinoma cell lines. The number of cells that invaded through the membrane was determined by light microscope (20X magnification) counterstained and invasion index (B,C) was calculated as described in Material and Methods and plotted in bar graphs. Both TFK1 and SZ1 showed significant decrease in number of invading cells by light microscope. P values were calculated with ANOVA analysis of variance along with Bonferroni post test. The error bar represents standard deviation. Differences were considered as statistically significant (*) when the P-value was less <0.05.</p