Early detection of pancreatic cancer: why, who, and how to screen

Multiparametric Characterization of the DSL-6A/C1 Pancreatic Cancer Model in Rats

The DSL-6A/C1 murine pancreatic ductal adenocarcinoma (PDAC) tumor model was established in Lewis rats and characterized through a comprehensive multiparametric analysis to compare it to other preclinical tumor models and explore potential diagnostic and therapeutical targets. DSL-6A/C1 tumors were histologically analyzed to elucidate PDAC features. The tumor microenvironment was studied for immune cell prevalence. Multiparametric MRI and PET imaging were utilized to characterize tumors, and 68Ga-FAPI-46-targeting cancer-associated fibroblasts (CAFs), were used to validate the histological findings. The histology confirmed typical PDAC characteristics, such as malformed pancreatic ductal malignant cells and CAFs. Distinct immune landscapes were identified, revealing an increased presence of CD8+ T cells and a decreased CD4+ T cell fraction within the tumor microenvironment. PET imaging with 68Ga-FAPI tracers exhibited strong tracer uptake in tumor tissues. The MRI parameters indicated increasing intralesional necrosis over time and elevated contrast media uptake in vital tumor areas. We have demonstrated that the DSL-6A/C1 tumor model, particularly due to its high tumorigenicity, tumor size, and 68Ga-FAPI-46 sensitivity, is a suitable alternative to established small animal models for many forms of preclinical analyses and therapeutic studies of PDAC.

Health State Utilities Associated with False-Positive Cancer Screening Results

INTRODUCTION

Early cancer detection can significantly improve patient outcomes and reduce mortality rates. Novel cancer screening approaches, including multi-cancer early detection tests, have been developed. Cost-utility analyses will be needed to examine their value, and these models require health state utilities. The purpose of this study was to estimate the disutility (i.e., decrease in health state utility) associated with false-positive cancer screening results.

METHODS

In composite time trade-off interviews using a 1-year time horizon, UK general population participants valued 10 health state vignettes describing cancer screening with true-negative or false-positive results. Each false-positive vignette described a common diagnostic pathway following a false-positive result suggesting lung, colorectal, breast, or pancreatic cancer. Every pathway ended with a negative result (no cancer detected). The disutility of each false positive was calculated as the difference between the true-negative and each false-positive health state, and because of the 1-year time horizon, each disutility can be interpreted as a quality-adjusted life-year decrement associated with each type of false-positive experience.

RESULTS

A total of 203 participants completed interviews (49.8% male; mean age = 42.0 years). The mean (SD) utility for the health state describing a true-negative result was 0.958 (0.065). Utilities for false-positive health states ranged from 0.847 (0.145) to 0.932 (0.059). Disutilities for false positives ranged from - 0.031 to - 0.111 (- 0.041 to - 0.111 for lung cancer; - 0.079 for colorectal cancer; - 0.031 to - 0.067 for breast cancer; - 0.048 to - 0.088 for pancreatic cancer).

CONCLUSION

All false-positive results were associated with a disutility. Greater disutility was associated with more invasive follow-up diagnostic procedures, longer duration of uncertainty regarding the eventual diagnosis, and perceived severity of the suspected cancer type. Utility values estimated in this study would be useful for economic modeling examining the value of cancer screening procedures.

Artificial intelligence in pancreatic cancer: diagnosis, limitations, and the future prospects-a narrative review

PURPOSE

This review aims to explore the role of AI in the application of pancreatic cancer management and make recommendations to minimize the impact of the limitations to provide further benefits from AI use in the future.

METHODS

A comprehensive review of the literature was conducted using a combination of MeSH keywords, including "Artificial intelligence", "Pancreatic cancer", "Diagnosis", and "Limitations".

RESULTS

The beneficial implications of AI in the detection of biomarkers, diagnosis, and prognosis of pancreatic cancer have been explored. In addition, current drawbacks of AI use have been divided into subcategories encompassing statistical, training, and knowledge limitations; data handling, ethical and medicolegal aspects; and clinical integration and implementation.

CONCLUSION

Artificial intelligence (AI) refers to computational machine systems that accomplish a set of given tasks by imitating human intelligence in an exponential learning pattern. AI in gastrointestinal oncology has continued to provide significant advancements in the clinical, molecular, and radiological diagnosis and intervention techniques required to improve the prognosis of many gastrointestinal cancer types, particularly pancreatic cancer.

Nanomedicine for overcoming therapeutic and diagnostic challenges associated with pancreatic cancer

Pancreatic cancer is the second leading cause of cancer-related death in the USA. The 5-year survival rate for pancreatic cancer is as low as 10%, making it one of the most deadly cancers. This dismal prognosis is caused, in part, by the lack of early detection and screening options, leading to late-stage detection of the disease, at a point at which chemotherapy is no longer effective. However, nanoparticle (NP) drug delivery systems have increased the efficacy of chemotherapeutics by improving the targeting ability of drugs to the tumor site, while also decreasing the risk of local and systemic toxicity. Such efforts can contribute to the development of early diagnosis and routine screening tests, which will drastically improve the survival rates and prognosis of patients with pancreatic cancer.

Designing optimal allocations for cancer screening using queuing network models

Cancer is one of the leading causes of death, but mortality can be reduced by detecting tumors earlier so that treatment is initiated at a less aggressive stage. The tradeoff between costs associated with screening and its benefit makes the decision of whom to screen and when a challenge. To enable comparisons across screening strategies for any cancer type, we demonstrate a mathematical modeling platform based on the theory of queuing networks designed for quantifying the benefits of screening strategies. Our methodology can be used to design optimal screening protocols and to estimate their benefits for specific patient populations. Our method is amenable to exact analysis, thus circumventing the need for simulations, and is capable of exactly quantifying outcomes given variability in the age of diagnosis, rate of progression, and screening sensitivity and intervention outcomes. We demonstrate the power of this methodology by applying it to data from the Surveillance, Epidemiology and End Results (SEER) program. Our approach estimates the benefits that various novel screening programs would confer to different patient populations, thus enabling us to formulate an optimal screening allocation and quantify its potential effects for any cancer type and intervention.

We describe a mathematical modeling methodology that offers quantitative insights into the potential benefits of screening and other interventions on cancer mortality. Our queuing-theoretic approach represents a potentially useful alternative to more traditional modeling approaches, in that it can provide more detailed results and entirely circumvents the need for simulations. Our methodology can be widely applied to estimate costs and benefits of screening strategies. By providing a detailed example of our method applied to epidemiological data, we hope to encourage greater uptake of this methodology in the community.

Applications of artificial intelligence (AI) in ovarian cancer, pancreatic cancer, and image biomarker discovery

BACKGROUND

Artificial intelligence (AI), including machine learning (ML) and deep learning, has the potential to revolutionize biomedical research. Defined as the ability to "mimic" human intelligence by machines executing trained algorithms, AI methods are deployed for biomarker discovery.

OBJECTIVE

We detail the advancements and challenges in the use of AI for biomarker discovery in ovarian and pancreatic cancer. We also provide an overview of associated regulatory and ethical considerations.

METHODS

We conducted a literature review using PubMed and Google Scholar to survey the published findings on the use of AI in ovarian cancer, pancreatic cancer, and cancer biomarkers.

RESULTS

Most AI models associated with ovarian and pancreatic cancer have yet to be applied in clinical settings, and imaging data in many studies are not publicly available. Low disease prevalence and asymptomatic disease limits data availability required for AI models. The FDA has yet to qualify imaging biomarkers as effective diagnostic tools for these cancers.

CONCLUSIONS

Challenges associated with data availability, quality, bias, as well as AI transparency and explainability, will likely persist. Explainable and trustworthy AI efforts will need to continue so that the research community can better understand and construct effective models for biomarker discovery in rare cancers.

Inflammation, Tumoral Markers and Interleukin-17, -10, and -6 Profiles in Pancreatic Adenocarcinoma and Chronic Pancreatitis

BACKGROUND

Interleukin profiles can be used as biochemical markers regarding the early diagnosis of pancreatic cancer.

AIMS

To assess CRP, CA 19-9, CEA levels, and interleukin-6, -10, and -17 profiles in pancreatic ductal adenocarcinoma, chronic pancreatitis was compared with a control group, and the correlation with pancreatic cancer survival.

METHODS

A total of 87 patients were prospective divided in pancreatic cancer (n = 53), chronic pancreatitis (n = 22) ,and control group (n = 12). The diagnosis of PDAC was made histologically. The diagnosis of chronic pancreatitis was based on medical history, imaging methods, and endoscopic ultrasound. Systemic concentrations of interleukins were measured using ELISA kits. The patients were followed at 1, 3, and 6 months.

RESULTS

CRP, CA 19-9, and CEA were higher in the pancreatic cancer group (p < 0.001). Interleukin-10 was significantly higher in the pancreatic cancer and chronic pancreatitis groups (p < 0.001). Interleukin-17 was statistically higher in the pancreatic cancer group (p < 0.0001). The cut-off of interleukin-17 of 0.273 had a sensitivity of 90.9 and a specificity of 80.9 with a curve under ROC of 0.80 in order to differentiate between pancreatic cancer and chronic pancreatitis. The serum levels of interleukins are not correlated with the stage of the disease. CRP, CA 19-9, CEA, and interleukin-6, -10, and -17 were lower in patients with survival more than 6 months.

CONCLUSIONS

We detected high levels of interleukin-6, -10, and -17 in chronic pancreatitis and pancreatic cancer. Serum interleukin-17 levels can discriminate between pancreatic cancer and chronic pancreatitis. The prognostic role of interleukins needs to be established.

Prognostic Value of lncRNA NEAT1 as a New Biomarker in Digestive System Tumors: a Systematic Study and Meta-analysis

OBJECTIVE

Nuclear paraspeckle assembly transcript 1 (NEAT1), a newly found lncRNA, is found abnormally expressed in digestive system tumors. This meta-analysis aims to evaluate the effect of NEAT1 on digestive system tumors.

METHODS

An analysis was conducted to investigate NEAT1 expression in digestive system tumors from the PubMed, Embase, and Web of Science databases. The relationship between NEAT1 expression and patient overall survival (OS) and clinicopathology was evaluated by correlation analysis with the pooled hazard ratio (HR), 95% confidence interval (CI), and odds ratio (OR).

RESULTS

A total of 12 published studies were enrolled in this meta-analysis. The NEAT1 overexpression was significantly associated with poor OS (HR = 1.64, 95% CI:1.41-1.91, p < 0.05), lymphatic metastasis (OR = 2.70, 95% CI: 2.02-3.61, p < 0.05), distal metastasis (OR = 3.01, 95% CI: 1.97-4.59, p < 0.05) and advanced tumor stage (OR = 3.04, 95% CI: 2.32-3.99, p < 0.05). However, digestive system tumor patients with high NEAT1 expression was not related to the patients' age (OR = 0.91, 95% CI: 0.65-1.26, p = 0.561), gender (OR = 1.04, 95% CI: 0.81-1.33, p = 0.761), tumor size (OR = 1.84, 95% CI: 0.88-3.88, p = 0.106), and tumor differentiation (OR = 0.86, 95% CI: 0.51-1.44, p = 0.570).

CONCLUSION

Collectively, NEAT1 can be used as a potential biomarker to predict the prognosis of patients with digestive system tumors, which is worth verifying in clinical practice.

Improved detectability of hypoattenuating focal pancreatic lesions by dual-layer computed tomography using virtual monoenergetic images

Background

Multidetector CT is the mainstay for radiologic evaluation of pancreatic pathology. Still, imaging of focal pancreatic lesions using MDCT is faced by a number of challenges that are related to the limited contrast between the lesion and surrounding parenchyma, such as detecting early-stage pancreatic cancer and subtle features of cystic lesions that point to malignancy. Dual-layer CT is the first dual-energy CT machine based on separation of high- and low-energy photons at the detector level. If improved contrast between the lesions and normal pancreatic parenchyma could be achieved on CT images, we may expect enhanced CT detection of pancreatic lesions. The purpose of this study was to evaluate whether virtual monoenergetic reconstructions generated using contrast-enhanced dual-layer CT could improve detectability of hypoattenuating focal pancreatic lesions compared to conventional polyenergetic reconstructions.

Results

Fifty-four lesions were identified and verified by histopathology or follow-up CT, MRCP, and/or EUS along with clinical data. Across the virtual monoenergetic spectrum, 40 KeV images had the highest contrast-to-noise and signal-to-noise ratios (p < 0.001, p < 0.001) and were significantly higher than conventional images (p < 0.001). Subjective scores for lesion visibility at low kiloelectron volt monoenergetic (40 and 50 KeV) images greatly exceeded conventional images (p < 0.001).

Conclusion

Low kiloelectron volt monoenergetic reconstructions of contrast-enhanced dual-layer CT significantly improve detectability of hypoattenuating focal pancreatic lesions compared to conventional polyenergetic reconstructions.

Vitamin B6, vitamin B12 and methionine and risk of pancreatic cancer: a meta-analysis

Background

Nutrients involved in one-carbon metabolism may play a key role in pancreatic carcinogenesis. The aim of this study was to examine the association between pancreatic cancer risk and intake or blood levels of vitamins B6, B12 and methionine via meta-analysis.

Methods

A systematic search was performed in PubMed, Web of Knowledge and Chinese National Knowledge Infrastructure (CNKI) up to April 2020 to identify relevant studies. Risk estimates and their 95% confidence intervals (CIs) were retrieved from the studies and combined by a random-effect model.

Results

A total of 18 studies were included in this meta-analysis on the association of vitamin B6, B12 and methionine with pancreatic cancer risk. The combined risk estimate (95% CI) of pancreatic cancer for the highest vs lowest category of vitamin B6 intake and blood pyridoxal 5′-phosphate (PLP, active form of vitamin B6) levels was 0.63 (0.48–0.79) and 0.65 (0.52–0.79), respectively. The results indicated a non-linear dose-response relationship between vitamin B6 intake and pancreatic risk. Linear dose–response relationship was found, and the risk of pancreatic cancer decreased by 9% for every 10 nmol/L increment in blood PLP levels. No significant association were found between pancreatic cancer risk and vitamin B12 intake, blood vitamin B12 levels, methionine intake and blood methionine levels.

Conclusion

Our study suggests that high intake of vitamin B6 and high concentration of blood PLP levels may be protective against the development of pancreatic cancer. Further research are warranted to confirm the results.

Status and future directions in the management of pancreatic cancer: potential impact of nanotechnology

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed at a late stage, has limited treatments, and patients have poor survival rates. It currently ranks as the seventh leading cause of cancer deaths globally and has increasing rates of diagnosis. Improved PDAC treatment requires the development of innovative, effective, and economical therapeutic drugs. The late stage diagnosis limits options for surgical resection, and traditional PDAC chemotherapeutics correlate with increased organ and hematologic toxicity. In addition, PDAC tumor tissue is dense and highly resistant to many traditional chemotherapeutic applications, making the disease difficult to treat and impeding options for palliative care. New developments in nanotechnology may offer innovative options for targeted PDAC therapeutic drug delivery. Nanotechnology can be implemented using multimodality methods that offer increased opportunities for earlier diagnosis, precision enhanced imaging, targeted long-term tumor surveillance, and controlled drug delivery, as well as improved palliative care and patient comfort. Nanoscale delivery methods have demonstrated the capacity to infiltrate the dense, fibrous tumor tissue associated with PDAC, increasing delivery and effectiveness of chemotherapeutic agents and reducing toxicity through the loading of multiple drug therapies on a single nano delivery vehicle. This review presents an overview of nanoscale drug delivery systems and multimodality carriers at the forefront of new PDAC treatments.

Quantitative parameters of intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI): potential application in predicting pathological grades of pancreatic ductal adenocarcinoma

Background

The aim of this study was to compare intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) parameters such as standard apparent diffusion coefficient (ADC_standard), pure diffusion coefficient (D_slow), pseudodiffusion coefficient (D_fast) and perfusion fraction (ƒ) for differentiating pancreatic ductal adenocarcinoma (PDAC) with different pathological grades.

Methods

Institutional Review Board of our hospital approved this study protocol. Subjects comprised 38 PDACs confirmed by pathology. Pancreatic multiple b values DWI with 15 b values of 0, 10, 20, 40, 60, 80, 100, 150, 200, 400, 800, 1,000, 1200, 1,500, and 2,000 s/mm² was performed using GE Discovery MR750 3.0T scanner. ADC_standard, D_slow, D_fast and ƒ values of all PDACs were calculated using mono- and bi-exponential models. Parameters of well/moderately differentiated and poorly differentiated PDAC were compared using Independent Sample t-test. P values <0.05 were considered significant.

Results

Mean D_slow value of well/moderately differentiated PDAC was significantly lower than that of poorly differentiated PDAC (0.540×10^-3vs. 0.676×10^-3 mm²/s, P<0.001). Mean ƒ value of well/moderately differentiated PDAC was significantly higher than that of poorly differentiated PDAC (60.3% vs. 38.4%, P<0.001). The area under curve value of ƒ in differentiating well/moderately differentiated PDAC from poorly differentiated PDAC was slightly higher than that of D_slow (0.894>0.865). When the D_slow value was less than or equal to 0.599×10^-3 mm²/s, the sensitivity and specificity were 100% and 84.6% respectively. When ƒ value was greater than 49.6%, the sensitivity and specificity were 92.0% and 84.6% respectively.

Conclusions

D_slow and ƒ derived from IVIM-DWI model can be used to distinguish well/moderately differentiated PDAC from poorly differentiated PDAC. And to serve this purpose, D_slow and ƒ have high diagnostic performance. IVIM-DWI is a promising and non-invasive tool for predicting pathological grade of PDAC.

LITAF is a potential tumor suppressor in pancreatic cancer

Early diagnosis of pancreatic cancer, one of the most deadly cancers with low survival rates, is difficult, and effective biomarkers are urgently needed. Lipopolysaccharide-induced tumor necrosis factor-α factor (LITAF) has been recently proposed as a potential tumor suppressor gene in several types of cancer. Here, we analyzed the biological function of LITAF in pancreatic cancer. The LITAF gene and protein levels were decreased in pancreatic tumor tissues compared with their paired adjacent non-cancerous tissues. In addition, patients with the lower LITAF protein expression had lower disease-free survival rates. The decreased LITAF expression correlated with LITAF promoter hypermethylation in pancreatic cancer cells and tissues. Moreover, promoter demethylation dose-dependently increased the LITAF transcription. Importantly, LITAF demethylation suppressed proliferation and cell cycle progression, and enhanced apoptosis of pancreatic cancer cells. Together, our results indicate that LITAF functions as a tumor suppressor gene in pancreatic cancer cells, and might serve as a novel biomarker for early diagnosis of pancreatic cancer.

Isolation of circulating tumor cells from pancreatic cancer by automated filtration

It is now widely recognized that the isolation of circulating tumor cells based on cell surface markers might be hindered by variability in their protein expression. Especially in pancreatic cancer, isolation based only on EpCAM expression has produced very diverse results. Methods that are independent of surface markers and therefore independent of phenotypical changes in the circulating cells might increase CTC recovery also in pancreatic cancer. We compared an EpCAM-dependent (IsoFlux) and a size-dependent (automated Siemens Healthineers filtration device) isolation method for the enrichment of pancreatic cancer CTCs. The recovery rate of the filtration based approach is dramatically superior to the EpCAM-dependent approach especially for cells with low EpCAM-expression (filtration: 52%, EpCAM-dependent: 1%). As storage and shipment of clinical samples is important for centralized analyses, we also evaluated the use of frozen diagnostic leukapheresis (DLA) as source for isolating CTCs and subsequent genetic analysis such as KRAS mutation detection analysis. Using frozen DLA samples of pancreatic cancer patients we detected CTCs in 42% of the samples by automated filtration.

Diagnostic value of selected markers and apoptotic pathways for pancreatic cancer

Pancreatic cancer occupies the fourth place as a cause of death from cancer, and the mortality rate is similar to the number of newly detected cases. Due to the late diagnosis, only 5-6% of patients with pancreatic cancer survive for five years. Given that early diagnosis is critical for improving patients' survival rates, there is an urgent need for the discovery and validation of new biomarkers with sufficient sensitivity and specificity to help diagnose pancreatic cancer early. Detection of serum tumor markers (CA19-9, CEA, CA125 and CA242) is conducive to the early diagnosis of pancreatic cancer. The combination of miR-16, miR-196a and CA19-9 plasma level was more effective, especially in early tumor screening. Furthermore, recent studies reported that mainly miR-21, miR-155 and miR-196 were dysregulated in IPMN (intraductal papillary mucinous neoplasms) and PanIN (pancreatic intraepithelial neoplasia) lesions, suggesting their usefulness as early biomarkers of these diseases. The reduced rate of apoptosis plays a crucial role in carcinogenesis, and it is one of the most important characteristics acquired by pancreatic cancer cells, which protects them from attack by the immune system and reduces the effectiveness of pharmacological treatment. This review summarizes the data concerning the clinical utility of selected biomarkers in pancreatic cancer patients. The review mainly focuses on the genetic aspects of signaling pathway disorders associated with apoptosis in the pathogenesis and diagnosis of pancreatic cancer.

KRAS mutations in blood circulating cell-free DNA: a pancreatic cancer case-control

The utility of KRAS mutations in plasma circulating cell-free DNA (cfDNA) samples as non-invasive biomarkers for the detection of pancreatic cancer has never been evaluated in a large case-control series. We applied a KRAS amplicon-based deep sequencing strategy combined with analytical pipeline specifically designed for the detection of low-abundance mutations to screen plasma samples of 437 pancreatic cancer cases, 141 chronic pancreatitis subjects, and 394 healthy controls. We detected mutations in 21.1% (N=92) of cases, of whom 82 (89.1%) carried at least one mutation at hotspot codons 12, 13 or 61, with mutant allelic fractions from 0.08% to 79%. Advanced stages were associated with an increased proportion of detection, with KRAS cfDNA mutations detected in 10.3%, 17,5% and 33.3% of cases with local, regional and systemic stages, respectively. We also detected KRAS cfDNA mutations in 3.7% (N=14) of healthy controls and in 4.3% (N=6) of subjects with chronic pancreatitis, but at significantly lower allelic fractions than in cases. Combining cfDNA KRAS mutations and CA19-9 plasma levels on a limited set of case-control samples did not improve the overall performance of the biomarkers as compared to CA19-9 alone. Whether the limited sensitivity and specificity observed in our series of KRAS mutations in plasma cfDNA as biomarkers for pancreatic cancer detection are attributable to methodological limitations or to the biology of cfDNA should be further assessed in large case-control series.

The association between dietary vitamin A intake and pancreatic cancer risk: a meta-analysis of 11 studies

Whether dietary vitamin A intake could reduce pancreatic cancer risk is still conflicting. We therefore conducted a meta-analysis to summarize the evidence from epidemiological studies. We searched the databases of PubMed and Web of Knowledge up to July 2016. Random model was used to combine study-specific relative risks (RR) and 95% confidence interval (CI). Publication bias was assessed by Egger regression asymmetry test and Begg's funnel plot. Eleven studies (10 case-control studies and 1 cohort study) involving 2705 pancreatic cancer cases were included in the present study. The RR (95% CI) of pancreatic cancer for highest category of vitamin A intake compared with lowest category was 0.839 (95% CI=0.712–0.988) with low heterogeneity detected (I²=17.8%, P_{heterogeneity}=0.274). The relationships were also significant for studies designed by case-control [RR=0.808, 95% CI=0.690–0.947], as well as in European population [RR=0.821, 95% CI=0.693–0.972]. No evidence of publication bias was found. This meta-analysis demonstrated that dietary vitamin A intake might inversely associated with the risk of pancreatic cancer.

Pancreatic ductal adenocarcinoma in BRCA2 mutation carriers

Germline BRCA2 mutations are the first known cause of inherited (familial) pancreatic ductal adenocarcinoma (PDAC). This tumor is the third most frequent cancer in carriers of germline BRCA2 mutations, as it occurs in around 10% of BRCA2 families. PDAC is known as one of the most highly lethal cancers, mainly because of its chemoresistance and frequently late diagnosis. Based on recent developments in molecular biology, a subgroup of BRCA2-associated PDAC has been created, allowing screening, early surgical treatment and personalized systemic treatment. BRCA2 germline mutation carriers who have ≥1 first-degree relative, or ≥2 blood relatives with PDAC, should undergo screening and regular follow-up based on magnetic resonance imaging and endoscopic ultrasound. The goal of screening is to detect early invasive PDAC and advanced precancerous lesions suitable for a stepwise surgical complete (R0) resection. Increasing evidence on the molecular role of the BRCA2 protein in the homologous recombination of DNA damages suggest that BRCA2-related PDAC are sensitive to agents causing DNA cross-linking damage, such as platinum salts, and treatments targeting rescue DNA repair pathways, such as poly(ADP-ribose) polymerase inhibitors that are currently under investigation.

Opportunities and Challenges for Pancreatic Circulating Tumor Cells

Sensitive and reproducible platforms have been developed for detection, isolation, and enrichment of circulating tumor cells (CTCs)-rare cells that enter the blood from solid tumors, including those of the breast, prostate gland, lung, pancreas, and colon. These might be used as biomarkers in diagnosis or determination of prognosis. CTCs are no longer simply detected and quantified; they are now used in ex vivo studies of anticancer agents and early detection. We review what we have recently learned about CTCs from pancreatic tumors, describing advances in their isolation and analysis and challenges to their clinical utility. We summarize technologies used to isolate CTCs from blood samples of patients with pancreatic cancer, including immunoaffinity and label-free physical attribute-based capture. We explain methods of CTC analysis and how findings from these studies might be used to detect cancer at earlier stages, monitor disease progression, and determine prognosis. We review studies that have expanded CTCs for testing of anticancer agents and how these approaches might be used to personalize treatment. Advances in the detection, isolation, and analysis of CTCs have increased our understanding of the dissemination and progression of pancreatic cancer. However, standardization of methodologies and prospective studies are needed for this emerging technology to have a significant effect on clinical care.

Screening for Pancreatic Adenocarcinoma Using Signals From Web Search Logs: Feasibility Study and Results

INTRODUCTION

People's online activities can yield clues about their emerging health conditions. We performed an intensive study to explore the feasibility of using anonymized Web query logs to screen for the emergence of pancreatic adenocarcinoma. The methods used statistical analyses of large-scale anonymized search logs considering the symptom queries from millions of people, with the potential application of warning individual searchers about the value of seeking attention from health care professionals.

METHODS

We identified searchers in logs of online search activity who issued special queries that are suggestive of a recent diagnosis of pancreatic adenocarcinoma. We then went back many months before these landmark queries were made, to examine patterns of symptoms, which were expressed as searches about concerning symptoms. We built statistical classifiers that predicted the future appearance of the landmark queries based on patterns of signals seen in search logs.

RESULTS

We found that signals about patterns of queries in search logs can predict the future appearance of queries that are highly suggestive of a diagnosis of pancreatic adenocarcinoma. We showed specifically that we can identify 5% to 15% of cases, while preserving extremely low false-positive rates (0.00001 to 0.0001).

CONCLUSION

Signals in search logs show the possibilities of predicting a forthcoming diagnosis of pancreatic adenocarcinoma from combinations of subtle temporal signals revealed in the queries of searchers.

Increased Incidence of Second Primary Pancreatic Cancer in Patients with Prior Colorectal Cancer: A Population-Based US Study

BACKGROUND

Identifying high-risk groups for pancreatic cancer (PC) may lead to earlier detection. We determined the risk of subsequent PC among survivors of sporadic colorectal cancer (CRC).

METHODS

We evaluated data from the US Surveillance, Epidemiology, and End Results registry to identify individuals with primary CRC between the years 1973-2006. Standardized incidence ratios (SIRs) and 95 % confidence interval (95 % CI) were calculated to compare the risk of subsequent primary PC in the study cohort to that of the standard population. Analysis was stratified by age at diagnosis of CRC and sex. CRC characteristics were compared among CRC survivors with and without PC. Multivariate sub-hazard ratios were calculated to identify factors associated with subsequent primary PC, using death from non-PC causes as a competing event.

RESULTS

Of the 273,144 patients with first primary CRC, 657 (0.24 %) developed subsequent PC. CRC survivors were more likely to develop PC (SIR 1.22; 95 % CI 1.09-1.35). Mean latency period (time between CRC and PC diagnosis) was 1, 3, and 5 years from index age of CRC 20-49, 50-64, and >65 years, respectively. Multivariate analysis showed CRC survivors >50 years had 3.5-fold, those with right-sided CRC had 1.2-fold, and those with localized and regional CRCs had sixfold and fivefold increased risk of PC, respectively.

CONCLUSION

This study suggests that CRC survivors have an increased risk of developing subsequent PC within 1-5 years. CRC survivors age >50 with localized/regional stage, and right-sided CRC have higher predisposition to PC.

Burden of cancer associated with type 2 diabetes mellitus in Japan, 2010-2030

Diabetes mellitus constitutes a major disease burden globally, and the prevalence of diabetes continues to increase worldwide. We aimed to estimate the burden of cancer associated with type 2 diabetes mellitus in Japan between 2010 and 2030. In this study, we estimated the population attributable fraction of cancer risk associated with type 2 diabetes in 2010 and 2030 using the prevalence estimates of type 2 diabetes in Japan from 1990 to 2030, summary hazard ratios of diabetes and cancer risk from a pooled analysis of eight large‐scale Japanese cohort studies, observed incidence/mortality of cancer in 2010 and predicted incidence/mortality for 2030 derived from the age–period–cohort model. Our results showed that between 2010 and 2030, the total numbers of cancer incidence and mortality were predicted to increase by 38.9% and 10.5% in adults aged above 20 years, respectively. In the number of excess incident cancer cases associated with type 2 diabetes, an increase of 26.5% in men and 53.2% in women is expected between 2010 and 2030. The age‐specific analysis showed that the population attributable fraction of cancer will increase in adults aged >60 years over time, but will not change in adults aged 20–59 years. In conclusion, this study suggests a modest but steady increase in cancers associated with type 2 diabetes.

This study provides the first comprehensive evidence on the current and future burden of cancer associated with type 2 diabetes mellitus. Between 2010 and 2030, the incident cancer cases associated with type 2 diabetes were found to increase constantly over time, particularly in liver, pancreas and colon in Japan. Given the prolonged life expectancy in Japan, increase in people living with type 2 diabetes and subsequent cancer will be a public health issue in the years to come.

Detection and isolation of circulating exosomes and microvesicles for cancer monitoring and diagnostics using micro-/nano-based devices

In the last several years, nanoscale vesicles that originate from tumor cells and which can be found circulating in the blood (i.e. exosomes and microvesicles) have been discovered to contain a wealth of proteomic and genetic information to monitor cancer progression, metastasis, and drug efficacy. However, the use of exosomes and microvesicles as biomarkers to improve patient care has been limited by their small size (30 nm-1 μm) and the extensive sample preparation required for their isolation and measurement. In this Critical Review, we explore the emerging use of micro and nano-technology to isolate and detect exosomes and microvesicles in clinical samples and the application of this technology to the monitoring and diagnosis of cancer.

Nutrition in Pancreatic Cancer: A Review

BACKGROUND

Pancreatic cancer is the fourth leading cause of cancer-related mortality in both genders. More than 80% of patients suffer from significant weight loss at diagnosis and over time develop severe cachexia. Early nutritional support is therefore essential.

SUMMARY

This review evaluates the different nutritional therapies, such as enteral nutrition, parenteral nutrition and special nutritional supplements, on nutritional status, quality of life and survival.

KEY MESSAGE

Due to the high prevalence of malnutrition and the rapid development of anorexia-cachexia-syndrome, early nutritional intervention is crucial and supported by clinical data.

PRACTICAL IMPLICATIONS

Enteral nutrition should be preferred over parenteral nutrition. Omega-3 fatty acids and l-carnitine are promising substances for the prevention of severe cachexia, but further randomized controlled trials are needed to establish generally accepted guidelines on nutrition in pancreatic cancer.

Dual-energy CT increases reader confidence in the detection and diagnosis of hypoattenuating pancreatic lesions

PURPOSE

To prospectively compare detection and reader confidence of pancreatic lesions using a standard multi-detector computed tomography (MDCT) imaging protocol to a dual-energy computed tomography (DECT) imaging protocol with additional virtual non-contrast series.

METHODS

60 subjects imaged for suspected or known pancreatic lesions were included. Subjects underwent pancreatic MDCT including non-contrast, pancreatic phase, and portal venous phase (PVP). The PVP was performed in dual energy mode. Virtual non-contrast and blended 120 kVp weighted images were created from the DECT data. Overall noise and absolute attenuation differences of pancreatic lesions and normal pancreatic tissue were measured. Images were read by two staff radiologists blinded to the underlying diagnosis. MDCT and DECT scans were reviewed separately to evaluate image quality and level of confidence in diagnosis of a pancreatic lesion.

RESULTS

Image quality was ranked excellent for 90 % and 95 % of the 120 kVp studies and 93 % and 95 % of the 100 kVp studies by readers 1 and 2, respectively. VNC was ranked sufficient quality or better by both readers. Average attenuation difference was 74 HU (120 kVp) and 71 HU (100 kVp). Average noise was 11.31 HU (120 kVp) and 15.89 HU (100 kVp). No lesions were missed by either approach. There was increased confidence in diagnostic interpretation in 14 % (± 9 % [95 % CI]) and 9 % (± 7 % [95 % CI]) of DECT scans compared to MDCT.

CONCLUSIONS

DECT compared to MDCT pancreatic imaging leads to increased reader confidence with identical diagnostic sensitivity for pathologically proven cases. This approach could be implemented as a single phase acquisition study with calculated VNC leading to a significant dose savings to the patient.

The necessity of an observational study on the interactions between allergic history and citrus fruit intake for the prevention of pancreatic cancer

While the main product of Jeju Island is citrus fruit and the prevalence of atopic dermatitis among the students who live there is relatively high, the incidence of pancreatic cancer is lowest in Korea. Systematic reviews reporting allergic history and intake of citrus fruit as protective factors against pancreatic cancer (PCC) were published in 2005 and 2008, respectively. Although there were discrepancies in the results of the subgroup analyses between case-control and cohort studies, it is necessary to evaluate an interaction effect between allergic history and intake of citrus fruits on PCC risk.

Anatomical, Physiological, and Molecular Imaging for Pancreatic Cancer: Current Clinical Use and Future Implications

Pancreatic adenocarcinoma is one of the deadliest human malignancies. Early detection is difficult and effective treatment is limited. Verifying the presence of micrometastatic dissemination and vessel invasion remains elusive, limiting radiological staging once this diagnosis is made. Diagnostic imaging provides independent tools to evaluate and characterize the biologic behavior of pancreatic cancer. Conventional anatomic imaging alone with either CT or MRI yields useful information on organ involvement but is limited in providing molecular and physiological information. Molecular imaging techniques such as PET or MRS provide information on metabolic and signaling pathways. Advanced MR sequences that target physiological parameters expand imaging options to characterize these tumors. By considering the parametric data from these three imaging approaches (anatomic, molecular, and physiological) we can better define specific tumor signatures. Such parametric characterization can provide insight into tumor metabolism, cellular density, protein expression, focal perfusion, and vascular permeability of these tumors. Radiogenomics research has already demonstrated ability to obtain information about cancer's genotype and phenotype; this is without invasive procedures or surgery. Further advances in these areas of experimental imaging hold promise to enable future clinical advances in detection and therapy of pancreatic cancer.

The promise of methylation on beads for cancer detection and treatment

Despite numerous technical hurdles, the realization of true personalized medicine is becoming a progressive reality for the future of patient care. With the development of new techniques and tools to measure the genetic signature of tumors, biomarkers are increasingly being used to detect occult tumors, determine the choice of treatment and predict outcomes. Methylation of CpG islands at the promoter region of genes is a particularly exciting biomarker as it is cancer-specific. Older methods to detect methylation were cumbersome, operator-dependent and required large amounts of DNA. However, a newer technique called methylation on beads has resulted in a more uniform, streamlined and efficient assay. Furthermore, methylation on beads permits the extraction and processing of miniscule amounts of methylated tumor DNA in the peripheral blood. Such a technique may aid in the clinical detection and treatment of cancers in the future.

Vitamin E intake and pancreatic cancer risk: a meta-analysis of observational studies

Background

Some epidemiological studies have suggested that vitamin E intake reduces the risk of pancreatic cancer; however, this conclusion has not been supported by all the published studies. We conducted a meta-analysis to assess the relationship between vitamin E intake and the risk of pancreatic cancer by combining the results from published articles.

Material/Methods

We searched the published studies that reported the relationship between vitamin E intake and pancreatic cancer risk using the PubMed, Web of Science, and Embase databases through December 31^st, 2014. Based on a fixed-effects or random-effects model, the RR and 95% CI were used to assess the combined risk.

Results

In total, 10 observational studies (6 case-control studies and 4 cohort studies) were included. The overall RR (95% CI) of pancreatic cancer for the highest vs. the lowest level of vitamin E intake was 0.81 (0.73, 0.89). We found little evidence of heterogeneity (I²=19.8%, P=0.255). In the subgroup analyses, we found an inverse association between vitamin E intake and pancreatic cancer risk both in the case-control and cohort studies. Additionally, this inverse association was not modified by different populations.

Conclusions

In our meta-analysis, there was an inverse association between vitamin E intake and the risk of pancreatic cancer. A high level of vitamin E might be a protective factor for populations at risk for pancreatic cancer.

SREBP1 regulates tumorigenesis and prognosis of pancreatic cancer through targeting lipid metabolism

Sterol regulatory element-binding protein 1 (SREBP1) is a known transcription factor of lipogenic genes, which plays important roles in regulating de novo lipogenesis. Accumulating evidences indicate SREBP1 is involved in tumorigenesis, yet its role in pancreatic cancer remains unclear. Here, we explored the expression characteristic and function of SREBP1 in pancreatic cancer. Analysis of 60 patients with pancreatic ducat cancer showed that SREBP1 level was significantly higher in pancreatic cancer than that in adjacent normal tissues. High expression of SREBP1 predicted poor prognosis in patients with pancreatic cancer. Multivariate analysis revealed that SREBP1 was an independent factor affecting overall survival. SREBP1 silencing resulted in proliferation inhibition and induction of apoptosis in pancreatic cancer cells. Mechanistically, lipogenic genes (acetyl-CoA carboxylase (ACC), fatty acid synthase (FASN), and stearoyl-CoA desaturase-1 (SCD1)) and de novo lipogenesis were promoted by SREBP1. Inhibition of lipogenic genes through specific inhibitors ablated SREBP1-mediated growth regulation. Furthermore, depletion of SREBP1 could suppress lipid metabolism and tumor growth in vivo. Our results indicate that SREBP1 had important role in tumor progression and appears to be a novel prognostic marker for pancreatic cancer.

Screening for pancreatic cancer

Even with improved cancer care generally, the incidence and death rate is increasing for pancreatic cancer. Concern exists that a further increase in deaths caused by pancreatic cancer will be seen as other causes of death, such as heart disease and other cancers, decline. Critical exploration of screening high-risk patients as a tool to reduce deaths from pancreatic cancer should be considered. Technological advances and improved understanding of pancreatic cancer biology provides an opportunity to identify and test a panel of early detection biomarkers easily, accurately, and inexpensively measured in blood, urine, stool, or saliva samples. These biomarkers may have additional usefulness in staging, stratification for treatment, establishing prognosis, and assessing response to therapy in this disease. Screening may prove to be one of several strategies to improve outcomes in a disease that has otherwise been difficult to defeat.

High-throughput and high-sensitivity quantitative analysis of serum unsaturated fatty acids by chip-based nanoelectrospray ionization-Fourier transform ion cyclotron resonance mass spectrometry: early stage diagnostic biomarkers of pancreatic cancer

In this study, Fourier transform ion cyclotron resonance mass spectrometry (FTICR MS) coupled with chip-based direct-infusion nanoelectrospray ionization source (CBDInanoESI) in a negative ion mode is first employed to evaluate the effect of serum and its corresponding supernatant matrixes on the recoveries of serum free fatty acids (FFAs) based on spike-and-recovery experimental strategy by adding analytes along with analog internal standard (IS). The recoveries between serum (69.8-115.6%) and the supernatant (73.6-99.0%) matrixes are almost identical. Multiple point internal standard calibration curves between the concentration ratios of individual fatty acids to ISs, (C(17:1) as IS of C(16:1), C(18:3), C(18:2), or C(18:1) or C(21:0) as IS of C(20:4) or C(22:6)) versus their corresponding intensity ratios were constructed for C(16:1), C(18:3), C(18:2), C(18:1), C(20:4) and C(22:6), respectively, with correlation coefficients of greater than 0.99, lower limits of detection between 0.3 and 1.8 nM, and intra- and inter-day precision (relative standard deviations <18%), along with the linear dynamic range of three orders of magnitude. Sequentially, this advanced analytical platform was applied to perform simultaneous quantitative and qualitative analysis of multiple targets, e.g., serum supernatant unsaturated FFAs from 361 participants including 95 patients with pancreatic cancer (PC), 61 patients with pancreatitis and 205 healthy controls. Experimental results indicate that the levels of C(18:1), C(18:2), C(18:3), C(20:4) and C(22:6), as well as the level ratios of C(18:2)/C(18:1) and C(18:3)/C(18:1) of the PC patients were significantly decreased compared with those of healthy controls and the patients with pancreatitis (p < 0.01). It is worth noting that the ratio of C(18:2)/C(18:1), polyunsaturated fatty acids (PUFAs) (C(18:2), C(18:3), C(20:4), and C(22:6)), panel a (C(16:1), C(18:3), C(18:2), C(20:4) and C(22:6)) and panel b (C(18:2)/C(18:1) and C(18:3)/C(18:1)) performed excellent diagnostic ability, with an area under the receiver operating characteristic curve of ≥0.869, sensitivity of ≥85.7%, and specificity of ≥86.7% for differentiating the early stage PC from non-cancer subjects, which are greatly higher than those of clinically used serum biomarker CA 19-9. More importantly, this platform can also provide a fast and easy way to quantify the levels of FFAs in less than 30 s per sample.

Monitoring pancreatic carcinogenesis by the molecular imaging of cathepsin E in vivo using confocal laser endomicroscopy

The monitoring of pancreatic ductal adenocarcinoma (PDAC) in high-risk populations is essential. Cathepsin E (CTSE) is specifically and highly expressed in PDAC and pancreatic intraepithelial neoplasias (PanINs), and its expression gradually increases along with disease progression. In this study, we first established an in situ 7,12-dimethyl-1,2-benzanthracene (DMBA)-induced rat model for PanINs and PDAC and then confirmed that tumorigenesis properties in this model were consistent with those of human PDAC in that CTSE expression gradually increased with tumor development using histology and immunohistochemistry. Then, using in vivo imaging of heterotopically implanted tumors generated from CTSE- overexpressing cells (PANC-1-CTSE) in nude mice and in vitro imaging of PanINs and PDAC in DMBA-induced rats, the specificity of the synthesized CTSE-activatable probe was verified. Quantitative determination identified that the fluorescence signal ratio of pancreatic tumor to normal pancreas gradually increased in association with progressive pathological grades, with the exception of no significant difference between PanIN-II and PanIN-III grades. Finally, we monitored pancreatic carcinogenesis in vivo using confocal laser endomicroscopy (CLE) in combination with the CTSE-activatable probe. A prospective double-blind control study was performed to evaluate the accuracy of this method in diagnosing PDAC and PanINs of all grades (>82.7%). This allowed us to establish effective diagnostic criteria for CLE in PDAC and PanINs to facilitate the monitoring of PDAC in high-risk populations.

Fatty acids found in dairy, protein and unsaturated fatty acids are associated with risk of pancreatic cancer in a case-control study

Although many studies have investigated meat and total fat in relation to pancreatic cancer risk, few have investigated dairy, fish and specific fatty acids (FAs). We evaluated the association between intake of meat, fish, dairy, specific FAs and related nutrients and pancreatic cancer. In our American-based Mayo Clinic case-control study 384 cases and 983 controls frequency matched on recruitment age, race, sex and residence area (Minnesota, Wisconsin or Iowa, USA) between 2004 and 2009. All subjects provided demographic information and completed 144-item food frequency questionnaire. Logistic regression-calculated odds ratios (ORs) and 95% confidence intervals (95% CIs) were adjusted for age, sex, cigarette smoking, body mass index and diabetes mellitus. Significant inverse association (trend p-value < 0.05) between pancreatic cancer and the groupings (highest vs. lowest consumption quintile OR [95% CI]) was as follows: meat replacement (0.67 [0.43-1.02]), total protein (0.58 [0.39-0.86]), vitamin B12 (0.67 [0.44, 1.01]), zinc (0.48 [0.32, 0.71]), phosphorus (0.62 [0.41, 0.93]), vitamin E (0.51 [0.33, 0.78]), polyunsaturated FAs (0.64 [0.42, 0.98]) and linoleic acid (FA 18:2) (0.62 [0.40-0.95]). Increased risk associations were observed for saturated FAs (1.48 [0.97-2.23]), butyric acid (FA 4:0) (1.77 [1.19-2.64]), caproic acid (FA 6:0) (2.15 [1.42-3.27]), caprylic acid (FA 8:0) (1.87 [1.27-2.76]) and capric acid (FA 10:0) (1.83 [1.23-2.74]). Our study suggests that eating a diet high in total protein and certain unsaturated FAs is associated with decreased risk of developing pancreatic cancer in a dose-dependent manner, whereas fats found in dairy increase risk.

Novel methylation biomarker panel for the early detection of pancreatic cancer

PURPOSE

Pancreatic cancer is the fourth leading cause of cancer deaths and there currently is no reliable modality for the early detection of this disease. Here, we identify cancer-specific promoter DNA methylation of BNC1 and ADAMTS1 as a promising biomarker detection strategy meriting investigation in pancreatic cancer.

EXPERIMENTAL DESIGN

We used a genome-wide pharmacologic transcriptome approach to identify novel cancer-specific DNA methylation alterations in pancreatic cancer cell lines. Of eight promising genes, we focused our studies on BNC1 and ADAMTS1 for further downstream analysis, including methylation and expression. We used a nanoparticle-enabled methylation on beads (MOB) technology to detect early-stage pancreatic cancers by analyzing DNA methylation in patient serum.

RESULTS

We identified two novel genes, BNC1 (92%) and ADAMTS1 (68%), that showed a high frequency of methylation in pancreatic cancers (n = 143), up to 100% in PanIN-3 and 97% in stage I invasive cancers. Using the nanoparticle-enabled MOB technology, these alterations could be detected in serum samples (n = 42) from patients with pancreatic cancer, with a sensitivity for BNC1 of 79% [95% confidence interval (CI), 66%-91%] and for ADAMTS1 of 48% (95% CI, 33%-63%), whereas specificity was 89% for BNC1 (95% CI, 76%-100%) and 92% for ADAMTS1 (95% CI, 82%-100%). Overall sensitivity using both markers is 81% (95% CI, 69%-93%) and specificity is 85% (95% CI, 71%-99%).

CONCLUSIONS

Promoter DNA methylation of BNC1 and ADAMTS1 is a potential biomarker to detect early-stage pancreatic cancers. Assaying the promoter methylation status of these genes in circulating DNA from serum is a promising strategy for early detection of pancreatic cancer and has the potential to improve mortality from this disease.

Polymorphisms in metabolism/antioxidant genes may mediate the effect of dietary intake on pancreatic cancer risk

OBJECTIVES

A source of variation for inconsistent dietary-pancreatic cancer associations may be individuals carrying constitutional metabolism/antioxidant gene variants that differentially benefit compared to homozygous individuals. Seventy-six tag single-nucleotide polymorphisms were genotyped in 13 candidate genes to test differential associations with pancreatic adenocarcinoma.

METHODS

A clinic-based case-control design was used to rapidly ascertain 251 cases and 970 frequency matched controls who provided blood samples and completed a 144-item food frequency questionnaire. Single-nucleotide polymorphisms were evaluated using a dominant genetic model and dietary categories split on controls' median intake. Logistic regression was used to calculate odds ratios and 95% confidence intervals, adjusted for potential confounders.

RESULTS

Significant increased associations (Bonferroni corrected P ≤ 0.0007) were observed for carriers of greater than or equal to 1 minor allele for rs3816257 (glucosidase, α; acid [GAA]) and lower intake of deep-yellow vegetables (1.90 [1.28-2.83]); and carriers of no minor allele for rs12807961 (catalase [CAT]) and high total grains intake (2.48 [1.50-4.09]), whereas those with greater than or equal to 1 minor allele had a decreasing slope (across grains). The reference group was no minor alleles with low dietary intake.

CONCLUSIONS

Interindividual variation in metabolism/antioxidant genes could interact with dietary intake to influence pancreatic cancer risk.

Metabolic system alterations in pancreatic cancer patient serum: potential for early detection

Background

The prognosis of pancreatic cancer (PC) is one of the poorest among all cancers, due largely to the lack of methods for screening and early detection. New biomarkers for identifying high-risk or early-stage subjects could significantly impact PC mortality. The goal of this study was to find metabolic biomarkers associated with PC by using a comprehensive metabolomics technology to compare serum profiles of PC patients to healthy control subjects.

Methods

A non-targeted metabolomics approach based on high-resolution, flow-injection Fourier transform ion cyclotron resonance mass spectrometry (FI-FTICR-MS) was used to generate comprehensive metabolomic profiles containing 2478 accurate mass measurements from the serum of Japanese PC patients (n=40) and disease-free subjects (n=50). Targeted flow-injection tandem mass spectrometry (FI-MS/MS) assays for specific metabolic systems were developed and used to validate the FI-FTICR-MS results. A FI-MS/MS assay for the most discriminating metabolite discovered by FI-FTICR-MS (PC-594) was further validated in two USA Caucasian populations; one comprised 14 PCs, six intraductal papillary mucinous neoplasims (IPMN) and 40 controls, and a second comprised 1000 reference subjects aged 30 to 80, which was used to create a distribution of PC-594 levels among the general population.

Results

FI-FTICR-MS metabolomic analysis showed significant reductions in the serum levels of metabolites belonging to five systems in PC patients compared to controls (all p<0.000025). The metabolic systems included 36-carbon ultra long-chain fatty acids, multiple choline-related systems including phosphatidylcholines, lysophosphatidylcholines and sphingomyelins, as well as vinyl ether-containing plasmalogen ethanolamines. ROC-AUCs based on FI-MS/MS of selected markers from each system ranged between 0.93 ±0.03 and 0.97 ±0.02. No significant correlations between any of the systems and disease-stage, gender, or treatment were observed. Biomarker PC-594 (an ultra long-chain fatty acid), was further validated using an independently-collected US Caucasian population (blinded analysis, n=60, p=9.9E-14, AUC=0.97 ±0.02). PC-594 levels across 1000 reference subjects showed an inverse correlation with age, resulting in a drop in the AUC from 0.99 ±0.01 to 0.90 ±0.02 for subjects aged 30 to 80, respectively. A PC-594 test positivity rate of 5.0% in low-risk reference subjects resulted in a PC sensitivity of 87% and a significant improvement in net clinical benefit based on decision curve analysis.

Conclusions

The serum metabolome of PC patients is significantly altered. The utility of serum metabolite biomarkers, particularly PC-594, for identifying subjects with elevated risk of PC should be further investigated.

Validation of four candidate pancreatic cancer serological biomarkers that improve the performance of CA19.9

Background

The identification of new serum biomarkers with high sensitivity and specificity is an important priority in pancreatic cancer research. Through an extensive proteomics analysis of pancreatic cancer cell lines and pancreatic juice, we previously generated a list of candidate pancreatic cancer biomarkers. The present study details further validation of four of our previously identified candidates: regenerating islet-derived 1 beta (REG1B), syncollin (SYCN), anterior gradient homolog 2 protein (AGR2), and lysyl oxidase-like 2 (LOXL2).

Methods

The candidate biomarkers were validated using enzyme-linked immunosorbent assays in two sample sets of serum/plasma comprising a total of 432 samples (Sample Set A: pancreatic ductal adenocarcinoma (PDAC, n = 100), healthy (n = 92); Sample Set B: PDAC (n = 82), benign (n = 41), disease-free (n = 47), other cancers (n = 70)). Biomarker performance in distinguishing PDAC from each control group was assessed individually in the two sample sets. Subsequently, multiparametric modeling was applied to assess the ability of all possible two and three marker panels in distinguishing PDAC from disease-free controls. The models were generated using sample set B, and then validated in Sample Set A.

Results

Individually, all markers were significantly elevated in PDAC compared to healthy controls in at least one sample set (p ≤ 0.01). SYCN, REG1B and AGR2 were also significantly elevated in PDAC compared to benign controls (p ≤ 0.01), and AGR2 was significantly elevated in PDAC compared to other cancers (p < 0.01). CA19.9 was also assessed. Individually, CA19.9 showed the greatest area under the curve (AUC) in receiver operating characteristic (ROC) analysis when compared to the tested candidates; however when analyzed in combination, three panels (CA19.9 + REG1B (AUC of 0.88), CA19.9 + SYCN + REG1B (AUC of 0.87) and CA19.9 + AGR2 + REG1B (AUC of 0.87)) showed an AUC that was significantly greater (p < 0.05) than that of CA19.9 alone (AUC of 0.82). In a comparison of early-stage (Stage I-II) PDAC to disease free controls, the combination of SYCN + REG1B + CA19.9 showed the greatest AUC in both sample sets, (AUC of 0.87 and 0.92 in Sets A and B, respectively).

Conclusions

Additional serum biomarkers, particularly SYCN and REG1B, when combined with CA19.9, show promise as improved diagnostic indicators of pancreatic cancer, which therefore warrants further validation.

Nutrients from fruit and vegetable consumption reduce the risk of pancreatic cancer

PURPOSE

Pancreatic cancer is a devastating disease for which the role of dietary factors remains inconclusive. Our objective was to evaluate the risk of pancreatic cancer associated with nutrients found in fruits and vegetables and nutrient supplementation using a clinic-based case-control design.

METHODS

Our study included 384 rapidly ascertained cases and 983 controls frequency-matched on age at time of recruitment (in 5-year increments), race, sex, and region of residence. All subjects provided demographic information and completed a 144-item food frequency questionnaire in which they reported no change to their diet within 5 years prior to entering the study. Logistic regression was used to calculate odds ratios and 95 % confidence intervals, adjusted for age, sex, smoking, body mass index, energy intake, and alcohol consumption.

RESULTS

Results show a significant (trend p value < 0.05) inverse association between pancreatic cancer and nutrient/supplement groupings in a dose-dependent manner including magnesium, potassium, selenium, alpha-carotene, beta-carotene, beta-cryptoxanthin, lutein and zeaxanthin, niacin, total alpha-tocopherol, total vitamin A activity, vitamin B6, and vitamin C. Adjusting for diabetes or total sugar intake did not result in significant changes.

CONCLUSION

We conclude that most nutrients obtained through consumption of fruits and vegetables may reduce the risk of developing pancreatic cancer.

Screening for pancreatic cancer: why, how, and who?

Pancreatic cancer is the fourth most common cause of cancer mortality in the United States, with 5-year survival rates for patients with resectable tumors ranging from 15% to 20%. However, most patients presenting with distant metastases, are not resectable, and have a 5-year survival rate of close to 0%. This demonstrates a need for improved screening to identify pancreatic cancer while the tumor is still localized and amenable to surgical resection. Studies of patients with pancreatic tumors incidentally diagnosed demonstrate longer median survival than tumors discovered only when the patient is symptomatic, suggesting that early detection may improve outcome. Recent evidence from genomic sequencing indicates a 15-year interval for genetic progression of pancreatic cancer from initiation to the metastatic stage, suggesting a sufficient window for early detection. Still, many challenges remain in implementing effective screening. Early diagnosis of pancreatic cancer relies on developing screening methodologies with highly sensitive and specific biomarkers and imaging modalities. It also depends on a better understanding of the risk factors and natural history of the disease to accurately identify high-risk groups that would be best served by screening. This review summarizes our current understanding of the biology of pancreatic cancer relevant to methods available for screening. At this time, given the lack of proven benefit in this disease, screening efforts should probably be undertaken in the context of prospective trials.

Plasma fatty acid composition in patients with pancreatic cancer: correlations to clinical parameters

Pancreatic cancer (PC) ranks as the fourth cause of cancer-related deaths in the Czech Republic. Evidence exists that deregulation of fatty acid (FA) metabolism is connected with some malignancies; therefore, we decided to analyze FA profile in plasma lipid classes in patients with PC with relation to tumor staging, nutritional status, and survival. The study included 84 patients (47 males, 37 females) with PC and 68 controls (36 males, 32 females). FA patterns were analyzed in plasma lipid classes by gas-chromatography. We observed increased proportion of total monounsaturated FA (MUFA) in PC group in all plasma lipid classes. These changes were connected with increased Δ9-desaturase (SCD1) and Δ5-desaturase indices. Correlations of dihomo-γ-linolenic acid (DHGLA) with these variables were opposite. Longer survival of patients was connected with higher content of EPA, DHA, and with lower SCD1 index, respectively. Plasma phospholipid proportions of α-linolenic acid, DHGLA, EPA, and n-3 polyunsaturated fatty acids displayed negative trend with tumor staging. Plasma lipid FA pattern in PC patients resulted from decreased dietary fat intake and increased de novo synthesis of FA with transformation into MUFA. Changes in FA profile implicated some pathophysiological mechanisms responsible for disturbed FA metabolism in PC and importance of appropriate nutritional support.

Pancreatic ductal adenocarcinoma is associated with a distinct urinary metabolomic signature

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is an aggressive malignancy with poor prognosis in part due to the lack of early detection and screening methods. Metabolomics provides a means for noninvasive screening of tumor-associated perturbations in cellular metabolism.

METHODS

Urine samples of PDAC patients (n = 32), healthy age and gender-matched controls (n = 32), and patients with benign pancreatic conditions (n = 25) were examined using (1)H-NMR spectroscopy. Targeted profiling of spectra permitted quantification of 66 metabolites. Unsupervised (principal component analysis, PCA) and supervised (orthogonal partial-least squares discriminant analysis, OPLS-DA) multivariate pattern recognition techniques were applied to discriminate between sample spectra using SIMCA-P(+) (version 12, Umetrics, Sweden).

RESULTS

Clear distinction between PDAC and controls was noted when using OPLS-DA. Significant differences in metabolite concentrations between cancers and controls (p < 0.001) were noted. Model parameters for both goodness of fit, and predictive capability were high (R (2) = 0.85; Q (2) = 0.59, respectively). Internal validation methods were used to confirm model validity. Sensitivity and specificity of the multivariate OPLS-DA model were summarized using a receiver operating characteristics (ROC) curve, with an area under the curve (AUROC) = 0.988, indicating strong predictive power. Preliminary analysis revealed an AUROC = 0.958 for the model of benign pancreatic disease compared with PDAC, and suggest that the cancer-associated metabolomic signature dissipates following RO resection.

CONCLUSIONS

Urinary metabolomics detected distinct differences in the metabolic profiles of pancreatic cancer compared with healthy controls and benign pancreatic disease. These preliminary results suggest that metabolomic approaches may facilitate discovery of novel pancreatic cancer biomarkers.

(18)F-FDG PET/CT imaging detects therapy efficacy of anti-EMMPRIN antibody and gemcitabine in orthotopic pancreatic tumor xenografts

PURPOSE

The objective of this study is to evaluate the therapeutic response to a novel monoclonal antibody targeting human extracellular matrix metalloproteinase inducer (EMMPRIN) in combination with gemcitabine in a pancreatic-tumor xenograft murine model by sequential 2-deoxy-2-[18F]fluoro-D-glucose ((18)F-FDG) positron emission tomography/computed tomgraphy (PET/CT) imaging.

PROCEDURES

Four groups of SCID mice bearing orthotopic pancreatic tumor xenografts were injected with phosphate-buffered saline, gemcitabine (120 mg/kg BW), anti-EMMPRIN antibody (0.2 mg), or combination, respectively, twice weekly for 2 weeks, while (18)F-FDG PET/CT imaging was performed weekly for 3 weeks. Changes in mean standardized uptake value (SUV(mean)) of (18)F-FDG and volume of tumors were determined.

RESULTS

The tumor SUV(mean) change in the group receiving combination therapy was significantly lower than those of the other groups. Tumor-volume changes of groups treated with anti-EMMPRIN monotherapy or combined therapy were significantly lower than that of the control group.

CONCLUSIONS

These data provide support for clinical studies of anti-EMMPRIN therapy with gemcitabine for pancreatic cancer treatment.