Adrenomedullin is up-regulated in patients with pancreatic cancer and causes insulin resistance in β cells and mice

New-Onset or Exacerbation of Diabetes Mellitus Is a Clue to the Early Diagnosis of Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC), which accounts for majority of pancreatic cancers, is one of the most lethal human malignancies. Most patients are diagnosed at an advanced stage after symptom development. Early diagnosis of PDAC in asymptomatic subjects is important to improve prognosis. Diabetes mellitus (DM) is a risk factor for PDAC, and DM, especially new-onset DM, has attracted attentions as a diagnostic clue to PDAC. However, the impact of DM as a diagnostic opportunity on the prognosis of PDAC is unclear. We here retrospectively reviewed 489 PDAC patients and compared the clinical characteristics and prognosis according to the opportunities for PDAC diagnosis. PDAC was diagnosed upon presentation of symptoms, such as pain and jaundice, in 318 cases including 151 DM patients, upon new-onset or exacerbation of long-standing DM in 53 asymptomatic patients, and upon incidental detection by medical check-up or follow-up/work-up of other diseases in 118 asymptomatic patients. Asymptomatic patients including those with DM had smaller tumors, earlier disease stage, and higher resectability rates than symptomatic patients. Asymptomatic patients diagnosed in association with DM had better prognosis (median survival time, 771 days) than those diagnosed due to symptoms (343 days, P < 0.001), and similar to those diagnosed by incidental detection (869 days). The survival advantage was not evident in symptomatic patients with DM-associated signs. In conclusion, patients diagnosed in association with DM at asymptomatic stages had better prognosis than those diagnosed with symptoms. DM-associated signs might provide a clue to the early diagnosis of PDAC among asymptomatic subjects.

Pre-operative dysglycemia is associated with decreased survival in patients with pancreatic neuroendocrine neoplasms

BACKGROUND

Diabetes mellitus is associated with increased risk of pancreatic cancer and impaired postresection survival. For pancreatic neuroendocrine neoplasms, no evidence is available for a similar effect of diabetes mellitus. The aim of this study was to evaluate the glycemic profile in patients with pancreatic neuroendocrine neoplasms and to assess the potential impact of glycemic control on the pathology and long-term outcomes in patients undergoing resection of pancreatic neuroendocrine neoplasms.

METHODS

Pancreatic resections from 2001 to 2017 for pancreatic neuroendocrine neoplasms were analyzed from prospective databases. Blood glucose and HbA1c levels were collected from preoperative tests. Preoperative dysglycemia was defined as a blood glucose ≥140 mg% and/or HbA1c ≥6.5%. Uni- and multivariate analyses were performed according to the presence of perioperative dysglycemia. Survival analyses were performed by Kaplan-Meier curves and Cox-proportional hazards method.

RESULTS

Four hundred and seventeen patients were analyzed. Medical history was positive for diabetes mellitus in 88 (21.1%) patients. Blood glucose evaluation identified 30 additional patients without a prior diagnosis of diabetes mellitus who had preoperative dysglycemia. No differences regarding pathologic characteristics or outcomes were detected between diabetics and non-diabetics. Conversely, patients with dysglycemia had greater rates of metastasis (16.8% vs 27.4%; P = .027) as well as vascular, perineural, and lympho-vascular involvement than those with normal blood glucose (89.2% vs 57.4%; P < .001, 90.0% vs 65.1%; P = .046, and 89.3% vs 61.3; P = .006, respectively). Preoperative dysglycemia was associated with impaired overall survival (hazard ratio = 1.57 [1.01-2.46]) and recurrence-free survival (hazard ratio = 1.78 [1.01-3.12]). By multivariate analysis, preoperative dysglycemia was independently associated with recurrence-free survival (hazard ratio 2.32 [1.29-4.17]), together with lymph-node involvement (hazard ratio = 2.01 [1.14-3.57]) and metastatic disease (hazard ratio = 5.10 [2.73-9.55]).

CONCLUSION

Preoperative dysglycemia, but not diabetes mellitus per se, is associated with advanced disease and impaired long-term outcomes in patients undergoing resection for a pancreatic neuroendocrine neoplasm. For those patients, closer surveillance and strict glycemic control are warranted.

Glucose metabolism during tumorigenesis in the genetic mouse model of pancreatic cancer

AIM

More than 40% of pancreatic ductal adenocarcinoma (PDAC) patients have glucose intolerance or diabetes. The association has led to two hypotheses: PDAC causes diabetes or diabetes shares risk factors for the development of PDAC. In order to elucidate the relationship between diabetes and PDAC, we investigated the glucose metabolism during tumorigenesis in the LSL-KrasG12D/+; LSL-Trp53R172H/+; and Pdx-1-Cre (KPC) mouse, a genetically engineered model of PDAC.

METHODS

Male and female KPCs have been fed with standard diet (SD) or high-fat diet (HFD). The imaging-based 4-class tumor staging was used to follow pancreatic cancer development. Not fasting glycemia, 4-h fasting glycemia, insulin, C-peptide, glucose tolerance after OGTT and abdominal fat volume were measured during tumorigenesis.

RESULTS

PDAC development did not lead to an overt diabetic phenotype or to any alterations in glucose tolerance in KPC fed with SD. Consumption of HFD induced higher body weight/abdominal fat volume and worsened glucose homeostasis both in control CRE mice and only in early tumorigenesis stages of the KPC mice, excluding that the cancer development itself acts as a trigger for the onset of dysmetabolic features.

CONCLUSION

Our data demonstrate that carcinogenesis in KPC mice is not associated with paraneoplastic diabetes.

Galectin-3 and S100A9: Novel Diabetogenic Factors Mediating Pancreatic Cancer-Associated Diabetes

OBJECTIVE

Pancreatic cancer-associated diabetes (PCDM) is a paraneoplastic phenomenon accounting for 1% of new-onset diabetes. We aimed to identify the mediators of PCDM and evaluate their usefulness in distinguishing PCDM from type 2 diabetes.

RESEARCH DESIGN AND METHODS

Secreted proteins of MIA PaCa-2 cells were identified by proteomics, and those with ≥10-fold overexpression in transcriptome analysis were assessed by bioinformatics and glucose uptake assay to identify candidate factors. Expression of factors was compared between tumors with and without PCDM by immunohistochemistry. Serum levels were measured in a training set including PC with and without PCDM, type 2 diabetes, pancreatitis, other pancreatic/peripancreatic tumors, and control subjects (n = 50 each). Cutoff values for differentiation between PCDM and type 2 diabetes from the training set were validated in a test set (n = 41 each).

RESULTS

Galectin-3 and S100A9 were overexpressed in tumors with PCDM and dose-dependently suppressed insulin-stimulated glucose uptake in C2C12 myotubes. In the training set, serum galectin-3 and S100A9 levels were exclusively increased in patients with PCDM and distinguished PCDM from type 2 diabetes (area under the curve [AUC] galectin-3: 0.73 [95% CI 0.64-0.83]; S100A9: 0.79 [95% CI 0.70-0.87]). Similar results were observed in the test set (AUC galectin-3: 0.83 [95% CI 0.74-0.92]; S100A9: 0.77 [95% CI 0.67-0.87]), with sensitivity and specificity 72.1% and 86.1%, respectively, for galectin-3 and 69.8% and 58.1% for S100A9 in differentiating between PCDM and type 2 diabetes.

CONCLUSIONS

Galectin-3 and S100A9 are overexpressed in PCDM tumors and mediate insulin resistance. Galectin-3 and S100A9 distinguish PCDM from type 2 diabetes in subjects with new-onset diabetes.

Early Detection of Pancreatic Cancer: Opportunities and Challenges

Most patients with pancreatic ductal adenocarcinoma (PDAC) present with symptomatic, surgically unresectable disease. Although the goal of early detection of PDAC is laudable and likely to result in significant improvement in overall survival, the relatively low prevalence of PDAC renders general population screening infeasible. The challenges of early detection include identification of at-risk individuals in the general population who would benefit from longitudinal surveillance programs and appropriate biomarker and imaging-based modalities used for PDAC surveillance in such cohorts. In recent years, various subgroups at higher-than-average risk for PDAC have been identified, including those with familial risk due to germline mutations, a history of pancreatitis, patients with mucinous pancreatic cysts, and elderly patients with new-onset diabetes. The last 2 categories are discussed at length in terms of the opportunities and challenges they present for PDAC early detection. We also discuss current and emerging imaging modalities that are critical to identifying early, potentially curable PDAC in high-risk cohorts on surveillance.

Phases of Metabolic and Soft Tissue Changes in Months Preceding a Diagnosis of Pancreatic Ductal Adenocarcinoma

BACKGROUND & AIMS

Identifying metabolic abnormalities that occur before pancreatic ductal adenocarcinoma (PDAC) diagnosis could increase chances for early detection. We collected data on changes in metabolic parameters (glucose, serum lipids, triglycerides; total, low-density, and high-density cholesterol; and total body weight) and soft tissues (abdominal subcutaneous fat [SAT], adipose tissue, visceral adipose tissue [VAT], and muscle) from patients 5 years before the received a diagnosis of PDAC.

METHODS

We collected data from 219 patients with a diagnosis of PDAC (patients) and 657 healthy individuals (controls) from the Rochester Epidemiology Project, from 2000 through 2015. We compared metabolic profiles of patients with those of age- and sex-matched controls, constructing temporal profiles of fasting blood glucose, serum lipids including triglycerides, cholesterol profiles, and body weight and temperature for 60 months before the diagnosis of PDAC (index date). To construct the temporal profile of soft tissue changes, we collected computed tomography scans from 68 patients, comparing baseline (>18 months before diagnosis) areas of SAT, VAT, and muscle at L2/L3 vertebra with those of later scans until time of diagnosis. SAT and VAT, isolated from healthy individuals, were exposed to exosomes isolated from PDAC cell lines and analyzed by RNA sequencing. SAT was collected from KRAS+/LSLG12D P53flox/flox mice with PDACs, C57/BL6 (control) mice, and 5 patients and analyzed by histology and immunohistochemistry.

RESULTS

There were no significant differences in metabolic or soft tissue features of patients vs controls until 30 months before PDAC diagnosis. In the 30 to 18 months before PDAC diagnosis (phase 1, hyperglycemia), a significant proportion of patients developed hyperglycemia, compared with controls, without soft tissue changes. In the 18 to 6 months before PDAC diagnosis (phase 2, pre-cachexia), patients had significant increases in hyperglycemia and decreases in serum lipids, body weight, and SAT, with preserved VAT and muscle. In the 6 to 0 months before PDAC diagnosis (phase 3, cachexia), a significant proportion of patients had hyperglycemia compared with controls, and patients had significant reductions in all serum lipids, SAT, VAT, and muscle. We believe the patients had browning of SAT, based on increases in body temperature, starting 18 months before PDAC diagnosis. We observed expression of uncoupling protein 1 (UCP1) in SAT exposed to PDAC exosomes, SAT from mice with PDACs, and SAT from all 5 patients but only 1 of 4 controls.

CONCLUSIONS

We identified 3 phases of metabolic and soft tissue changes that precede a diagnosis of PDAC. Loss of SAT starts 18 months before PDAC identification, and is likely due to browning. Overexpression of UCP1 in SAT might be a biomarker of early-stage PDAC, but further studies are needed.

Plasma midregional proadrenomedullin (MR-proADM) concentrations and their biological determinants in a reference population

BACKGROUND

Midregional proadrenomedullin (MR-proADM) is emerging as a prognostic biomarker for detecting the failure of multiple organs. Establishment of scientifically robust reference intervals facilitates interpretation of laboratory test results. The objectives of this study were (i) to establish reliable reference intervals for plasma MR-proADM using a commercially available automated fluoroimmunoassay in apparently healthy individuals, and (ii) to identify biological determinants of MR-proADM concentrations.

METHODS

A total of 506 questionnaire-identified apparently healthy adults were enrolled in a single-center, cross-sectional study. A final reference group (n=172) was selected after exclusion of obese individuals, those with increased values of laboratory biomarkers indicating asymptomatic myocardial injury or dysfunction, ongoing inflammation, diabetes, dyslipidemia and renal dysfunction and outliers.

RESULTS

The 2.5th and 97.5th percentile intervals for MR-proADM values in the reference group (90% confidence interval) were 0.21 (0.19-0.23) and 0.57 (0.55-0.59) nmol/L, respectively. Although older age, higher values of HbA1c, C-reactive protein, B-type natriuretic peptide and body mass index, together with a history of smoking and a decreased estimated glomerular filtration rate were significantly associated with increasing concentrations of MR-proADM in both univariate and multivariate analyses, magnitudes of these relationships were modest and did not substantially influence MR-proADM reference intervals. Sex-dependent difference in MR-proADM reference intervals was not detected [0.19 (0.16-0.22)-0.56 (0.54-0.60) nmol/L in females vs. 0.22 (0.20-0.25)-0.58 (0.57-0.63) nmol/L in males].

CONCLUSIONS

Our study successfully established robust reference intervals for MR-proADM concentrations in plasma. Considering the negligible influence of potential biological determinants on plasma MR-proADM, we recommend the adoption of single reference intervals for adult population as a whole.

Glycated serum proteins: High in pancreatic cancer and low in preeclampsia

Glycated serum protein (GSP, measured as serum fructosamine concentration in μmol/L) is a product of glycation reaction between glucose and serum proteins in the blood circulation. GSP is used along with blood glucose, glycated hemoglobin (HbA1c), and glycated albumin as indicators of glycemic control for diabetic patients. However, a systematic comparison of the GSP levels in different types of human diseases has not been reported. In this study, 62,698 clinical lab test results of GSP levels in patients with 61 clinically defined diseases over the past 5 years in our hospital were retrieved and compared to that of 1861 clinical lab test results in healthy individuals. Based on the mean (SD), median, and p (-Log₁₀p) values, we found that patients with type 2 diabetes, hepatic encephalopathy, pancreatic cancer, healthy individuals >65 years old, and cerebral arteriosclerosis had significantly (p<0.05, -Log₁₀p>1.30) increased whereas patients with 49/61 diseases including preeclampsia, nephrotic syndrome, sepsis, lupus erythematous, and leukemia had significantly decreased GSP levels compared to that of healthy controls. Among the 61 diseases, type 2 diabetes and leukemia had the highest -Log₁₀p values (>274) and lupus erythematous, nephrotic syndrome, and gastric cancer had -Log₁₀p values >140. Revealing the molecular mechanisms especially those underlying the decreased GSP levels in most of human diseases might make GSP levels serve more clinical purposes in future.

Total Serum Cholesterol and Pancreatic Cancer: A Nested Case-Control Study

BACKGROUND

Pancreatic cancer is the third leading cause of cancer-related death in the United States. Total serum cholesterol (TSC) may predict cancer risk, although its role independent of statins remains elusive. We examined the association between TSC and pancreatic cancer risk independent of statins.

METHODS

A nested case-control analysis was conducted among statin-naïve patients within The Health Improvement Network (THIN), a United Kingdom-based general practice database. Cases were >40 years old and diagnosed with pancreatic cancer after at least 6 months of follow-up. Controls were selected by incidence density sampling and matched by age, sex, practice site, and follow-up. Primary exposure was TSC (mmol/L) prior to index date. Conditional logistic regression estimated ORs for pancreatic cancer risk associated with TSC. Sensitivity analyses were conducted among nondiabetics.

RESULTS

Among 1,241 cases and 3,307 matched controls, an average 8% reduction was observed in pancreatic cancer risk per mmol/L increase in TSC [OR 0.92, 95% confidence interval (CI): 0.85-1.00; nondiabetics: OR 0.91, 95% CI: 0.83-0.99]. When TSC was measured at 12-month intervals prior to diagnosis, the OR between TSC and pancreatic cancer was 0.88 at 0 to 12 months (95% CI: 0.77-1.00; nondiabetics: OR 0.81, 95% CI: 0.68-0.96). No significant association was seen at subsequent discrete intervals before index date.

CONCLUSIONS

TSC is a significant predictor of short-term risk for pancreatic cancer. This risk increase associated with lower TSC was independent of statins.

IMPACT

TSC could serve as a biomarker for risk stratification, screening, and early diagnosis of pancreatic cancer in future clinical prediction models.

Pancreatic Cancer Following Incident Diabetes in African Americans and Latinos: The Multiethnic Cohort

Background

Diabetes has been proposed to be a risk factor for and a consequence of pancreatic cancer (PC). The relationship between recent-onset diabetes and PC is not well understood, and data in minorities are sparse. We examined the relationships between recent-onset diabetes and PC incidence in African Americans and Latinos in the Multiethnic Cohort.

Methods

A total of 48 995 African Americans and Latinos without prior diabetes and cancer at baseline (1993-1996) were included in the study. Questionnaires, Medicare data, and California hospital discharge files were used to identify new diabetes diagnoses. Cox regressions were used to calculate hazard ratios (HRs) and 95% confidence intervals (CIs) for cancer associated with diabetes and with diabetes duration.

Results

A total of 15 833 (32.3%) participants developed diabetes between baseline and 2013. A total of 408 incident PC cases were identified during follow-up. Diabetes was associated with PC (HRage75 = 2.39, 95% CI = 1.91 to 2.98). Individuals with recent-onset diabetes (within three or fewer years of PC diagnosis) had a greater risk compared with those with long-term diabetes across all ages. The HRage75 for recent-onset diabetes was 4.08 (95% CI = 2.76 to 6.03) in Latinos and 3.38 (95% CI = 2.30 to 4.98) in African Americans.

Conclusions

Diabetes was associated with a more than twofold higher risk of PC in African Americans and Latinos, but recent-onset diabetes was associated with a 2.3-fold greater increase in risk of PC than long-standing diabetes. Our findings support the hypothesis that recent-onset diabetes is a manifestation of PC and that long-standing diabetes is a risk factor for this malignancy.

Type-3c Diabetes Mellitus, Diabetes of Exocrine Pancreas - An Update

BACKGROUND

The incidence of diabetes is increasing steeply; the number of diabetics has doubled over the past three decades. Surprisingly, the knowledge of type 3c diabetes mellitus (T3cDM) is still unclear to the researchers, scientist and medical practitioners, leading towards erroneous diagnosis, which is sometimes misdiagnosed as type 1 diabetes mellitus (T1DM), or more frequently type 2 diabetes mellitus (T2DM). This review is aimed to outline recent information on the etiology, pathophysiology, diagnostic procedures, and therapeutic management of T3cDM patients.

METHODS

The literature related to T3cDM was thoroughly searched from the public domains and reviewed extensively to construct this article. Further, existing literature related to the other forms of diabetes is reviewed for projecting the differences among the different forms of diabetes. Detailed and updated information related to epidemiological evidence, risk factors, symptoms, diagnosis, pathogenesis and management is structured in this review.

RESULTS

T3cDM is often misdiagnosed as T2DM due to the insufficient knowledge differentiating between T2DM and T3cDM. The pathogenesis of T3cDM is explained which is often linked to the history of chronic pancreatitis, pancreatic cancer. Inflammation, and fibrosis in pancreatic tissue lead to damage both endocrine and exocrine functions, thus leading to insulin/glucagon insufficiency and pancreatic enzyme deficiency.

CONCLUSION

Future advancements should be accompanied by the establishment of a quick diagnostic tool through the understanding of potential biomarkers of the disease and newer treatments for better control of the diseased condition.

Pancreatic cancer associated with obesity and diabetes: an alternative approach for its targeting

BACKGROUND

Pancreatic cancer (PC) is among foremost causes of cancer related deaths worldwide due to generic symptoms, lack of effective screening strategies and resistance to chemo- and radiotherapies. The risk factors associated with PC include several metabolic disorders such as obesity, insulin resistance and type 2 diabetes mellitus (T2DM). Studies have shown that obesity and T2DM are associated with PC pathogenesis; however, their role in PC initiation and development remains obscure.

MAIN BODY

Several biochemical and physiological factors associated with obesity and/or T2DM including adipokines, inflammatory mediators, and altered microbiome are involved in PC progression and metastasis albeit by different molecular mechanisms. Deep understanding of these factors and causal relationship between factors and altered signaling pathways will facilitate deconvolution of disease complexity as well as lead to development of novel therapies. In the present review, we focuses on the interplay between adipocytokines, gut microbiota, adrenomedullin, hyaluronan, vanin and matrix metalloproteinase affected by metabolic alteration and pancreatic tumor progression.

CONCLUSIONS

Metabolic diseases, such as obesity and T2DM, contribute PC development through altered metabolic pathways. Delineating key players in oncogenic development in pancreas due to metabolic disorder could be a beneficial strategy to combat cancers associated with metabolic diseases in particular, PC.

Contribution of biomarkers for pancreatic cancer-associated new-onset diabetes to pancreatic cancer screening

BACKGROUND

Pancreatic cancer (PaC) is one of the deadliest types of tumor, and it is regarded as a fatal disease, with a 5-year survival rate less than 10%. Most clinical diagnoses for PaC are made at an advanced stage because of the insidious onset of the disease, which leads to an extremely poor prognosis.

RECENT FINDINGS

The relationship between diabetes mellitus (DM) and PaC has been established by several decades of research, and the prevalence of DM in patients with PaC has been reported to be 40%, with half of the patients having developed new-onset DM within 2 years or less. Increasing evidence suggests that new-onset DM is associated with a high prevalence of PaC, and PaC resection ameliorates DM. Therefore, screening for PaC may be needed in patients with newly developed DM.

PURPOSE

The objective of this review was to present our current understanding of biomarkers for PaC-associated new-onset DM (PCAND), to offer a perspective on the prospects and problems of using this strategy for early screening to differentiate PCAND from new-onset type 2 DM not associated with PaC and to suggest candidate biomarkers to use for PaC screening in patients with new-onset DM. Finding sensitive and specific biomarkers to manage these patients constitutes a challenge for the research community and for public health policies.

Exploring the bi-directional relationship between pancreatic cancer and diabetes mellitus: a retrospective study

Objective

To explore the bi-directional between pancreatic cancer (PC) and diabetes mellitus (DM); focusing on the prevalence, temporal association and impact on survival outcomes.

Methods

A retrospective audit of pancreatic cancer patients from the institutional clinical database (CaNISC) between January 2012 and April 2018.

Results

A total of 131 patients were analysed, 58 patients carried a diagnosis of diabetes mellitus. The median overall survival for diabetes mellitus patients was 12.0 months (95 CI, 5.9 to 18.1 months) in comparison to 13.0 months (95% CI, 8.6 to 17.3 months) in non-diabetes mellitus patients (p = 0.334).

Conclusion

There was no significant difference in the overall survival between DM and non-DM patients.

The Interface of Pancreatic Cancer With Diabetes, Obesity, and Inflammation: Research Gaps and Opportunities: Summary of a National Institute of Diabetes and Digestive and Kidney Diseases Workshop

A workshop on "The Interface of Pancreatic Cancer with Diabetes, Obesity, and Inflammation: Research Gaps and Opportunities" was held by the National Institute of Diabetes and Digestive and Kidney Diseases on October 12, 2017. The purpose of the workshop was to explore the relationship and possible mechanisms of the increased risk of pancreatic ductal adenocarcinoma (PDAC) related to diabetes, the role of altered intracellular energy metabolism in PDAC, the mechanisms and biomarkers of diabetes caused by PDAC, the mechanisms of the increased risk of PDAC associated with obesity, and the role of inflammatory events and mediators as contributing causes of the development of PDAC. Workshop faculty reviewed the state of the current knowledge in these areas and made recommendations for future research efforts. Further knowledge is needed to elucidate the basic mechanisms contributing to the role of hyperinsulinemia, hyperglycemia, adipokines, and acute and chronic inflammatory events on the development of PDAC.

Model to Determine Risk of Pancreatic Cancer in Patients With New-Onset Diabetes

BACKGROUND & AIMS

Of patients with new-onset diabetes (NOD; based on glycemic status) older than 50 years, approximately 1% are diagnosed with pancreatic cancer (PC) within 3 years. We aimed to develop and validate a model to determine risk of PC in patients with NOD.

METHODS

We retrospectively collected data from 4 independent and nonoverlapping cohorts of patients (N = 1,561) with NOD (based on glycemic status; data collected at date of diagnosis and 12 months previously) in the Rochester Epidemiology Project from January 1, 2000 through December 31, 2015 to create our model. The model weighed scores for 3 factors identified in the discovery cohort to be most strongly associated with PC (64 patients with PC and 192 with type 2 diabetes): change in weight, change in blood glucose, and age at onset of diabetes. We called our model Enriching New-Onset Diabetes for Pancreatic Cancer (ENDPAC). We validated the locked-down model and cutoff score in an independent population-based cohort of 1,096 patients with diabetes; of these, 9 patients (82%) had PC within 3 years of meeting the criteria for NOD.

RESULTS

In the discovery cohort, the END-PAC model identified patients who developed PC within 3 years of diabetes onset (area under receiver operating characteristic curve 0.87); a score of at least 3 identified patients who developed PC with 80% sensitivity and specificity. In the validation cohort, a score of at least 3 identified 7 of 9 patients with PC (78%) with 85% specificity; the prevalence of PC in patients with a score of at least 3 (3.6%) was 4.4-fold greater than in patients with NOD. A high END-PAC score in patients who did not have PC (false positives) was often due to such factors as recent steroid use or different malignancy. An ENDPAC score no higher than 0 (in 49% of patients) meant that patients had an extremely low risk for PC. An END-PAC score of at least 3 identified 75% of patients in the discovery cohort more than 6 months before a diagnosis of PC.

CONCLUSIONS

Based on change in weight, change in blood glucose, and age at onset of diabetes, we developed and validated a model to determine risk of PC in patients with NOD based on glycemic status (END-PAC model). An independent prospective study is needed to further validate this model, which could contribute to early detection of PC.

Pancreatic cancer-derived exosomes suppress the production of GIP and GLP-1 from STC-1 cells in vitro by down-regulating the PCSK1/3

One hallmark of pancreatic cancer (PC) is the high prevalence of pancreatic cancer-associated diabetes mellitus (PC-DM), but the mechanisms remain to be elucidated. Patients with PC who are diagnosed with new-onset diabetes/prediabetes have recently been shown to display significantly lower levels of glucose-dependent insulinotropic peptide (GIP) secreted mainly by enteroendocrine cells. We hypothesized that PC-derived exosomes are responsible for the decreased levels of incretins in patients with PC-DM. In this study, exosomes were successfully isolated from PANC-1, MIA PaCa-2 and SW620 cells and characterized. Only the exosomes from MIA PaCa-2 cells (Exo-Mia) reduce the production of GIP and glucagon-like peptide-1 (GLP-1) from STC-1 cells in vitro in a concentration- and time-dependent manner. Moreover, Exo-Mia increased the levels of the Gip and proglucagon mRNAs and decreased the expression of proprotein convertase subtilisin/kexin type 1/3 (PCSK1/3), which is responsible for the post-translational processing of Gip and proglucagon. Furthermore, differentially expressed exosomal miRNAs (miR-6796-3p, miR-6763-5p, miR-4750-3p and miR-197-3p) were identified and considered to be responsible for the inhibitory effects on GIP and GLP-1 production. To further determine the approach of cancer-derived exosomes reaching enteroendocrine cells, we analyzed the uptake and distribution of exosomes in animal model. It was observed that exosomes infused into the intestinal cavity were more easily internalized by the intestinal epithelium than exosomes injected into blood. In conclusion, pancreatic cancer-derived exosomes (Exo-Mia) suppress the synthesis of GIP and GLP-1 from STC-1 cells in vitro by down-regulating the PCSK1/3. Moreover, it may be the pancreatic juice that transport cancer-derived exosomes to target cells (K and L cells) in the gut.

Pancreatic cancer survival analysis defines a signature that predicts outcome

Pancreatic ductal adenocarcinoma (PDAC) is the third leading cause of cancer death in the US. Despite multiple large-scale genetic sequencing studies, identification of predictors of patient survival remains challenging. We performed a comprehensive assessment and integrative analysis of large-scale gene expression datasets, across multiple platforms, to enable discovery of a prognostic gene signature for patient survival in pancreatic cancer. PDAC RNA-Sequencing data from The Cancer Genome Atlas was stratified into Survival+ (>2-year survival) and Survival-(<1-year survival) cohorts (n = 47). Comparisons of RNA expression profiles between survival groups and normal pancreatic tissue expression data from the Gene Expression Omnibus generated an initial PDAC specific prognostic differential expression gene list. The candidate prognostic gene list was then trained on the Australian pancreatic cancer dataset from the ICGC database (n = 103), using iterative sampling based algorithms, to derive a gene signature predictive of patient survival. The gene signature was validated in 2 independent patient cohorts and against existing PDAC subtype classifications. We identified 707 candidate prognostic genes exhibiting differential expression in tumor versus normal tissue. A substantial fraction of these genes was also found to be differentially methylated between survival groups. From the candidate gene list, a 5-gene signature (ADM, ASPM, DCBLD2, E2F7, and KRT6A) was identified. Our signature demonstrated significant power to predict patient survival in two distinct patient cohorts and was independent of AJCC TNM staging. Cross-validation of our gene signature reported a better ROC AUC (≥ 0.8) when compared to existing PDAC survival signatures. Furthermore, validation of our signature through immunohistochemical analysis of patient tumor tissue and existing gene expression subtyping data in PDAC, demonstrated a correlation to the presence of vascular invasion and the aggressive squamous tumor subtype. Assessment of these genes in patient biopsies could help further inform risk-stratification and treatment decisions in pancreatic cancer.

The Role of Insulin-like Growth Factor (IGF) Axis in Early Diagnosis of Pancreatic Adenocarcinoma (PDAC)

New-onset diabetes mellitus (DM) is one of the first symptoms of pancreatic adenocarcinoma (PDAC). The frequency of endocrine disorders is estimated between 40% and 80% in patients with pancreatic cancer. DM is a risk factor for cancer development but it may also be a consequence of the tumor growth. Data confirming the existence of a relationship between long standing type 2 DM and an increased risk of PDAC comes from numerous clinical studies. Insulin resistance phenomenon and hyperinsulinemia may result in the increased proliferation of pancreatic islets which in turn may cause a predisposition to cancer development. In contrast, it is proved that new-onset DM among patients over 50 years old significantly increases the risk of PDAC recognition. Insulin-like growth factor 1 (IGF-1) and their complex proteins, IGF binding proteins, which comprise the IGF axis play a crucial role in carbohydrate metabolism disorders and, studies have shown that they may contribute to PDAC growth. Some studies confirm that IGF-1 is connected with early carcinogenesis in animals and humans. Assessing the levels of these proteins may thus be helpful in early recognition of PDAC in patients with recently detected endocrine disorders, especially pancreatic DM.

Fasting Blood Glucose Levels Provide Estimate of Duration and Progression of Pancreatic Cancer Before Diagnosis

BACKGROUND & AIMS

It is unclear how long pancreatic ductal adenocarcinomas (PDACs) are present before diagnosis. Patients with PDAC usually develop hyperglycemia and diabetes before the tumor is identified. If early invasive PDACs are associated with hyperglycemia, the duration of hyperglycemia should associate with the time that they have had the tumor.

METHODS

We collected data on patients with PDACs from medical databases in Olmsted County, Minnesota, from 2000 through 2015 and from the Mayo Clinic's tumor registry from January 1, 1976, through January 1, 2017. We compared glycemic profiles of patients with PDAC (cases) compared with patients without cancer, matched for age and sex (controls). We analyzed temporal fasting blood glucose (FBG) profiles collected for 60 months before patients received a PDAC diagnosis (index date) (n = 219) (cohort A), FBG profiles of patients with resected PDAC (n = 526) stratified by tumor volume and grade (cohort B), and temporal FBG profiles of patients with resected PDACs from whom long-term FBG data were available (n = 103) (cohort C). The primary outcome was to estimate duration of presence of invasive PDAC before its diagnosis based on hyperglycemia, defined as significantly higher (P < .05) FBG levels in cases compared with controls.

RESULTS

In cohort A, the mean FBG did not differ significantly between cases and controls 36 months before the index date. Hyperglycemia was first noted 36 to 30 months before PDAC diagnosis in all cases, those with or without diabetes at baseline and those with or without resection at diagnosis. FBG level increased until diagnosis of PDAC. In cohort B, the mean FBG did not differ significantly in controls vs cases with PDACs below 1.0 mL. The smallest tumor volume associated with hyperglycemia was 1.1 to 2.0 mL; FBG level increased with tumor volume. FBG varied with tumor grade: well- or moderately differentiated tumors (5.8 mL) produced the same FBG levels as smaller, poorly differentiated tumors (1.5 mL) (P < .001). In cohort C, the duration of prediagnostic hyperglycemia for cases with large-, medium-, or small-volume PDACs was 36 to 24, 24 to 12, and 12 to 0 months, respectively. PDAC resection resolved hyperglycemia, regardless of tumor location.

CONCLUSIONS

In a case-control study of patients with PDAC from 2 databases, we associated FBG level with time to PDAC diagnosis and tumor volume and grade. Patients are hyperglycemic for a mean period of 36 to 30 months before PDAC diagnosis; this information might be incorporated into strategies for early detection.

Comparison of Fasting Human Pancreatic Polypeptide Levels Among Patients With Pancreatic Ductal Adenocarcinoma, Chronic Pancreatitis, and Type 2 Diabetes Mellitus

OBJECTIVES

Human pancreatic polypeptide (HPP) is a hormone secreted by the ventral pancreas. While postprandial HPP levels have been studied in chronic pancreatitis (CP) and pancreatic ductal adenocarcinoma (PDAC), there are limited data on fasting HPP in these diseases.

METHODS

Fasting serum HPP was measured in the following groups of patients: CP with diabetes mellitus (DM) (n = 16), CP without DM (n = 34), PDAC with new-onset DM (n = 50), PDAC without DM (n = 49), new-onset type 2 DM (n = 50), and controls without DM (n = 49). Sixty-six had type 3c DM (CP with DM, n = 16; PDAC with new-onset DM, n = 50).

RESULTS

Median fasting HPP levels (in picograms per milliliter) were similar among all groups. Median (interquartile range) HPP levels in new-onset type 2 DM (n = 50; 288.3 [80.1-1072.1]) were similar to those in type 3c DM (n = 66; 242.3 [64.9-890.9]) (P = 0.71). In PDAC (n = 99), HPP values were similar in pancreatic head (n = 75) versus body/tail (n = 24) tumors (245.3 [64.3-1091.3] vs 334.7 [136.1-841.5]; P = 0.95), regardless of DM.

CONCLUSIONS

Fasting HPP levels are similar in CP, PDAC, and controls regardless of glycemic status.

Can pancreatic cancer be detected by adrenomedullin in patients with new-onset diabetes? The PaCANOD cohort study protocol

INTRODUCTION

Pancreatic cancer is a leading cause of cancer-related death. Its diagnosis is often delayed and patients are frequently found to have unresectable disease. Patients diagnosed with new-onset diabetes have an 8-fold risk of harboring pancreatic cancer. Adrenomedullin has been claimed to mediate diabetes in pancreatic cancer. New screening tools are needed to develop an early diagnosis protocol.

METHODS

Patients aged 45-75 years within 2 years of first fulfilling the ADA criteria for diabetes will be prospectively enrolled in this study. Sepsis, renal failure, microangiopathy, pregnancy, acute heart failure and previous malignancies will be considered as exclusion criteria.

RESULTS

440 patients diagnosed with new-onset diabetes will be enrolled and divided into 2 groups: one with high adrenomedullin levels and one with low adrenomedullin levels. Patients will undergo 3 years' follow-up to detect pancreatic cancer development.

CONCLUSIONS

Identifying a marker for pancreatic cancer among high-risk patients such as new-onset diabetics might lead to the identification of a subpopulation needing to be screened in order to enable early diagnosis and treatment of a highly lethal tumor.

TRIAL REGISTRATION

This trial was registered at ClinicalTrials.gov on May 25, 2015 under registration number NCT02456051.

Favorable glycemic response after pancreatoduodenectomy in both patients with pancreatic cancer and patients with non-pancreatic cancer

Diabetes mellitus (DM) is prevalent in patients with pancreatic cancer and tends to improve after tumor resection. However, the glycemic response of non-pancreatic cancer patients after surgery has not been examined in detail. We aimed to investigate the changes in glucose metabolism in patients with pancreatic cancer or non-pancreatic cancer after pancreatoduodenectomy (PD).We prospectively enrolled 48 patients with pancreatic cancer and 56 patients with non-pancreatic cancer, who underwent PD. Glucose metabolism was assessed with fasting glucose, glycated hemoglobin (HbA1c), plasma C-peptide and insulin, quantitative insulin check index (QUICKI), and a homeostatic model assessment of insulin resistance (HOMA-IR) and β cell (HOMA-β) before surgery and 6 months after surgery. Patients were divided into 2 groups: "improved" and "worsened" postoperative glycemic response, according to the changes in HbA1c and anti-diabetic medication. New-onset DM was defined as diagnosis of DM ≤ 2 years before PD, and cases with DM diagnosis >2 years preceding PD were described as long-standing DM.After PD, insulin resistance (IR), as measured by insulin, HOMA-IR and QUICKI, improved significantly, although C-peptide and HOMA-β decreased. At 6 months after PD, new-onset DM patients showed improved glycemic control in both pancreatic cancer patients (75%) and non-pancreatic cancer patients (63%). Multivariate analysis showed that long-standing DM was a significant predictor for worsening glucose control (odds ratio = 4.01, P = .017).Favorable glycemic control was frequently observed in both pancreatic cancer and non-pancreatic cancer after PD. PD seems to contribute improved glucose control through the decreased IR. New-onset DM showed better glycemic control than long-standing DM.

Increased serum levels of betatrophin in pancreatic cancer-associated diabetes

Long-standing diabetes or glucose intolerance is recognized as a crucial event in the process of pancreatic cancer. Betatrophin, a novel liver-derived hormone, promotes β-cell proliferation and improves glucose intolerance. However, the relationship between betatrophin and PDAC-associated diabetes is not fully understood. To evaluate the serum betatrophin levels in PDAC-associated diabetes, a total 105 Taiwanese subjects including 15 healthy subjects, and 12 patients having PDAC with normal glucose tolerance (PDAC-NGT), 12 patients having PC with impaired glucose tolerance (PDAC-IGT), and 66 patients having PC with diabetes mellitus (PDAC-DM) were enrolled for this study. Serum betatrophin and carbohydrate antigen 19-9 (CA19-9) levels were analyzed by enzyme-linked immunosorbent assay (ELISA). Compared to healthy subjects, PDAC patients had higher levels of betatrophin and CA19-9. Consistently, betatrophin protein was significantly expressed in pancreatic ductal of PDAC-associated DM patients using immunohistochemistry (IHC) method. Furthermore, multivariate regression analysis showed the betatrophin was significantly and positively independent with T category (β= 0.605, P=0.010), serum albumin (β= 0. 423, P=0.021), lipase (β= 0.292, P=0.039), and blood urea nitrogen (BUN) (β= 0.303, P=0.040). Further, the betatrophin was three folds of having PDAC-associated diabetes with the highest odds ratio [OR=3.39; 95% CI (1.20–9.57); P=0.021) and receiver operating characteristic (ROC) curve analysis showed that AUC value of betarophin was 0.853 which is slightly larger than AUC value of CA19-9 (0.792) in PDAC-DM patients. Interestingly, AUC value of betarophin plus CA19-9 was 0.988 in PDAC-DM patients. Therefore, betatrophin combined CA19-9 may serve as a potential biomarker for PDAC-associated diabetes.

A Silent Asymptomatic Solid Pancreas Tumor in a Nonsmoking Athletic Female: Pancreatic Ductal Adenocarcinoma

A silent solid endocrine tumor of pancreas, intraductal adenocarcinoma of pancreas, is the fourth leading cancer-related death in the US. However, it is expected to become the third leading cause by 2030 owing to delayed diagnosis and slow progress in management. Chronic pancreatitis is at risk for pancreatic ductal adenocarcinoma (PDAC). PDAC is diagnostic with transabdominal sonogram, blood test such as carbohydrate antigen 19-9 (CA 19-9), and imaging. PDAC has a dismal prognosis. The survival rate in 5 years is barely 6%, while late detection rate is 80–85% with unresectable stage upon diagnosis. Here, we present a 51-year-old asymptomatic female with intermittent constipation and abdominal pain for 1 month with obstructive jaundice with PDAC with liver metastasis.

Diabetes and the Pancreatobiliary Diseases

PURPOSE OF REVIEW

The emphasis of this review article is to bring to the forefront the spectrum of pancreatobiliary disorders and their association with diabetes. We hope to systematically discuss the link between diabetes and disorders of the pancreas including acute and chronic pancreatitis, as well as pancreatic cancer. We also hope to review and highlight the literature with respect to other cancers of the biliary tree including gallbladder and cholangiocarcinoma. Lastly, we discuss diabetes and biliary dyskinesia.

RECENT FINDINGS

Newer cohort studies suggest the presence of diabetes to increase the severity and worsen outcomes in acute pancreatitis. Post pancreatitis diabetes is a novel disease entity being increasingly recognized. The use of pancreatic enzyme replacement therapy (PERT) in chronic pancreatitis may attenuate the risk of endocrine dysfunction. Pancreatic cancer may either be the consequence of diabetes or a presenting manifestation. The use of anti-diabetic medications may confer protection against development of pancreatic cancer. Gallbladder adenocarcinoma and cholangiocarcinoma risks are elevated in those with underlying diabetes. Diabetes can directly impact or deteriorate outcome of acute and chronic pancreatitis and well as pancreatobiliary malignancies. It could also occur as a result of loss of endocrine function after pancreatitis. Like many areas of the digestive tract, biliary motility could be impacted by diabetes.

Pancreatic Cancer Screening

PURPOSE OF REVIEW

This review describes the rationale for pancreatic cancer screening, outlines groups that are at elevated risk for pancreatic cancer, and summarizes the relative risk in each setting. We also review the methods available for performing pancreatic cancer screening and the recommended screening intervals.

RECENT FINDINGS

Several genetic mutations have been identified that increase the risk for pancreatic cancer. Most are rare, however, and at-risk individuals are most often those with a strong family history of pancreatic cancer (with multiple family members affected) but no identifiable genetic mutation. Known genetic syndromes that increase the risk for pancreatic cancer include hereditary pancreatitis, familial atypical mole and multiple melanoma, Peutz-Jeghers syndrome, Lynch syndrome, BRCA mutations, and Li-Fraumeni syndrome. Genetic testing should be performed in conjunction with genetic counseling, and testing of an affected family member is preferred if possible.The goal of pancreatic cancer screening is to identify pancreatic cancer at an early, curable stage or, ideally, to identify precancerous lesions that can be resected to prevent the development of cancer. Imaging can be performed with either endoscopic ultrasound (EUS) or magnetic resonance cholangiopancreatography (MRCP). These techniques are generally considered to be complementary, although an advantage of EUS is that cysts or solid lesions can be sampled at the time of the procedure. Published results of small cohorts of high-risk patients in pancreatic cancer screening programs have demonstrated a high prevalence of small cystic lesions identified on EUS or MRCP, which often represent side-branch intraductal papillary mucinous neoplasms (IPMN). Knowledge of conditions and syndromes that increase pancreatic cancer risk allows one to identify those patients that may benefit from pancreatic cancer screening. As we gather evidence from large, international, multicenter cohorts of patients at high-risk for pancreatic cancer who are undergoing screening and as our understanding of the genetic underpinnings of pancreatic cancer improve, recommendations on screening will continue to be refined.

Early detection of sporadic pancreatic cancer: time for change

Sporadic pancreatic cancer amounts to ∼90% of all pancreatic cancers. It is a gloomy depressive disease and the most recalcitrant malignancy, with a very low 5-year survival (3-6%). At present, diagnostic methods are commonly applied, as used half a century ago, after the appearance of local and systemic symptoms (abdominal and back pain, cholestasis, painless jaundice, fatigue, anorexia, weight loss, anemia, peripheral phlebitis, and cachexia). Unfortunately, these symptoms are harbingers of an advanced disease. The subsequent imaging methods may offer additional information on the location, size, and morphology of the lesion, but they do not influence the prognosis. Radical surgery may be offered to 15-20% of patients. The relapses after surgery are frequent and chemotherapy may be palliative. Preventive programs represent the only possibility of improvement. We propose the first multistep and multidisciplinary preventive program for early detection of sporadic pancreatic cancer for the differential identification of average-risk patients who probably have the disease from those who do not.

Plasmid pLXSN-Mediated Adrenomedullin Gene Therapy for Cerebral Vasospasm Following Subarachnoid Hemorrhage in Rats

Background

The aim of this study was to investigate the protective effect of ADM gene mediated by plasmid pVAX1 on cerebral vasospasm (CVS) after subarachnoid hemorrhage (SAH).

Material/Methods

The recombinant plasmid pVAX-ADM was successfully established, and 40 SD rats were randomly divided into normal saline, pVAX1, pVAX1-ADM low-dose, pVAX1-ADM mid-dose, and pVAX1-ADM high-dose groups. The circumference and diameter of basilar artery, diameter of middle cerebral artery and internal carotid artery, and thickness of basilar artery wall were observed. The levels of circulating endothelial cells (CEC) and levels of regional cerebral blood flow (rCBF) of the parietal cortex were detected at different time-points. The expression levels of serum ADM, ET-1, and NOS of each group and the neurological functions were compared.

Results

The circumference and diameter of basilar artery and the diameter of the middle cerebral artery and internal carotid artery in pVAX1-ADM groups were significantly longer than those in the saline group and pVAX1 group (P<0.05), but the thickness of the basilar artery wall in pVAX1-ADM groups was significantly lower (P<0.05), and the levels of growth or decrease were both dose-dependent (P<0.05). Compared with the saline group and pVAX1 group, the expression levels of serum ADM, NOS, and rCBF in pVAX1-ADM groups were significantly higher (P<0.05), but the levels of serum ET-1 and CEC were significantly lower (P<0.05). The scores of neurobehavioral functions of pVAX1-ADM groups were significantly lower (P<0.05), and the scores were also dose-dependent (P<0.05).

Conclusions

The recombinant eukaryotic expression plasmid pVAX1-ADM can significantly relieve cerebral vasospasm, increase the expression of serum ADM and NOS, and decrease the expression of serum ET-1 in a rat model of CVS; it is dose-dependent and can also improve nervous system function.

The role of adrenomedullin in the pathogenesis of gastric cancer

Adrenomedullin has been shown to be overexpressed in many tumors, including gastric cancer tumors; however, its mechanism of action remains unclear. In this study, we examined the role of adrenomedullin in the pathogenesis of gastric cancer. Using clinical specimens and immunohistochemistry, we found that the expression levels of adrenomedullin and its receptors are inordinately elevated as compared to the adjacent non-tumor gastric tissues. We used siRNA gene silencing, in BGC-823 gastric cancer cell lines, to target adrenomedullin genes, and found that increased adrenomedullin expression results in the proliferation of tumor cells, tumor invasion, and metastasis. Furthermore, we found that under hypoxic conditions, gastric cancer BGC-823 cells exhibit higher expression levels of adrenomedullin and various other related proteins. Our results indicate the involvement of adrenomedullin in microvessel proliferation and partially in the release of hypoxia in solid tumors. Knockdown of adrenomedullin expression, at the protein level, reduced the levels of phosphoprotein kinase B and B-cell lymphoma 2 but increased the levels of cleaved-caspase3 and Bcl 2 associated x protein (Bax). Therefore, we hypothesized siRNA targeting of adrenomedullin genes inhibits various serine/threonine kinases via a signaling pathway that induces cell apoptosis. SiRNA targeting of adrenomedullin genes and green fluorescent control vectors were used to transfect BGC-823 cells, and western blot analyses were used to detect changes in the rates of autophagy in related proteins using confocal laser scanning microscopy. No significant changes were detected. Therefore, the knockdown of adrenomedullin and its receptors may represent a novel treatment strategy for gastric cancer.

Pancreatic Cancer Heralded by Worsening Glycemic Control: A Report of Two Cases

Pancreatic ductal adenocarcinoma is the third leading cause of cancer-related death in the United States. Since it is usually diagnosed at an advanced stage, its prognosis remains poor. The initial presentation varies according to the tumor location. The most common presenting signs are weight loss, jaundice, and pain. Several epidemiological, clinical, and experimental studies over the past 2 decades have shown that long-standing diabetes is a modest risk factor for pancreatic cancer. However, new-onset diabetes has also been observed to be an early manifestation of pancreatic cancer. We report 2 cases where worsening glycemic control led to the diagnosis of pancreatic cancer.

Early detection of pancreatic cancer: impact of high-resolution imaging methods and biomarkers

High-resolution imaging methods (HRIMs) and biomarkers present the second step of pancreatic cancer (PC) diagnostics in at-risk individuals. These include patients with positive risk factors, early symptoms, nonresponders to the initial antidiabetic therapy, patients older than 50 years of age with new-onset unstable diabetes requiring insulin as well as patients with long-term insulin-non-dependent diabetes and recent (up to 6 months) failure of antidiabetic therapy. The procedures should be started without delay and the co-operation between the primary and tertiary medical centers is highly desirable. An early indication of HRIMs and biomarkers is a prerequisite for the diagnosis of a resectable PC. This publication reviews the recent contribution of HRIMs and biomarkers toward an early diagnosis of PC.

Type 3c (pancreatogenic) diabetes mellitus secondary to chronic pancreatitis and pancreatic cancer

Diabetes mellitus is a group of diseases defined by persistent hyperglycaemia. Type 2 diabetes, the most prevalent form, is characterised initially by impaired insulin sensitivity and subsequently by an inadequate compensatory insulin response. Diabetes can also develop as a direct consequence of other diseases, including diseases of the exocrine pancreas. Historically, diabetes due to diseases of the exocrine pancreas was described as pancreatogenic or pancreatogenous diabetes mellitus, but recent literature refers to it as type 3c diabetes. It is important to note that type 3c diabetes is not a single entity; it occurs because of a variety of exocrine pancreatic diseases with varying mechanisms of hyperglycaemia. The most commonly identified causes of type 3c diabetes are chronic pancreatitis, pancreatic ductal adenocarcinoma, haemochromatosis, cystic fibrosis, and previous pancreatic surgery. In this Review, we discuss the epidemiology, pathogenesis, and clinical relevance of type 3c diabetes secondary to chronic pancreatitis and pancreatic ductal adenocarcinoma, and highlight several important knowledge gaps.

The impact of diabetes mellitus on survival following resection and adjuvant chemotherapy for pancreatic cancer

BACKGROUND

Diabetes mellitus is frequently observed in pancreatic cancer patients and is both a risk factor and an early manifestation of the disease.

METHODS

We analysed the prognostic impact of diabetes on the outcome of pancreatic cancer following resection and adjuvant chemotherapy using individual patient data from three European Study Group for Pancreatic Cancer randomised controlled trials. Analyses were carried out to assess the association between clinical characteristics and the presence of preoperative diabetes, as well as the effect of diabetic status on overall survival.

RESULTS

In total, 1105 patients were included in the analysis, of whom 257 (23%) had confirmed diabetes and 848 (77%) did not. Median (95% confidence interval (CI)) unadjusted overall survival in non-diabetic patients was 22.3 (20.8-24.1) months compared with 18.8 (16.9-22.1) months for diabetic patients (P=0.24). Diabetic patients were older, had increased weight and more co-morbidities. Following adjustment, multivariable analysis demonstrated that diabetic patients had an increased risk of death (hazard ratio: 1.19 (95% CI 1.01, 1.40), P=0.034). Maximum tumour size of diabetic patients was larger at randomisation (33.6 vs 29.7 mm, P=0.026).

CONCLUSIONS

Diabetes mellitus was associated with increased tumour size and reduced survival following pancreatic cancer resection and adjuvant chemotherapy.

Diabetes associated with pancreatic ductal adenocarcinoma is just diabetes: Results of a prospective observational study in surgical patients

BACKGROUND

Identification of a specific diabetes signature associated to pancreatic ductal carcinoma (PDAC) could be a key to detect asymptomatic, early stage tumors. We aim to characterize the clinical signature and the pathogenetic factors of the different types of diabetes associated with PDAC, based on the time between diabetes and cancer diagnosis.

METHODS

Prospective observational study on 364 PDAC patients admitted to a referral center for pancreatic disease. Hospital and/or outpatient medical records were reviewed. Blood biochemical values including fasting blood glucose, insulin and/or C-peptide, glycosylated hemoglobin and anti-islet antibodies were determined. Diabetes onset was assessed after surgery and during follow-up.

RESULTS

The prevalence of diabetes in patients was 67%. Considering 174 patients (47.8%) already having diabetes when diagnosed with PDAC (long duration, short duration, concomitant), the clinical and biochemical profile was similar to that of patients with type 2 diabetes (T2D). Diabetes was associated with known risk factors (i.e., age, sex, family history for diabetes and increased BMI) and both beta-cell dysfunction and insulin resistance were present. Considering 70 patients (19.2%) with onset of diabetes after PDAC diagnosis (early and late onset), the strongest predictor was the loss of beta-cell mass following pancreatectomy in patients with risk factors for T2D.

CONCLUSION

Different types of diabetes according to the time between diabetes and PDAC diagnosis are clinical entities widely overlapping with T2D. Therefore, the success of a strategy considering diabetes onset as a marker of asymptomatic PDAC will largely depend on our ability to identify new diabetes-unrelated biomarkers of PDAC.

Pancreas Volume and Fat Deposition in Diabetes and Normal Physiology: Consideration of the Interplay Between Endocrine and Exocrine Pancreas

The pancreas is comprised of exocrine and endocrine components. Despite the fact that they are derived from a common origin in utero, these two compartments are often studied individually because of the different roles and functions of the exocrine and endocrine pancreas. Recent studies have shown that not only type 1 diabetes (T1D), but also type 2 diabetes (T2D), is characterized by a deficit in beta-cell mass, suggesting that pathological changes in the pancreas are critical events in the natural history of diabetes. In both patients with T1D and those with T2D, pancreas mass and exocrine function have been reported to be reduced. On the other hand, pancreas volume and pancreatic fat increase with obesity. Increased beta-cell mass with increasing obesity has also been observed in humans, and ectopic fat deposits in the pancreas have been reported to cause beta-cell dysfunction. Moreover, neogenesis and transdifferentiation from the exocrine to the endocrine compartment in the postnatal period are regarded as a source of newly formed beta-cells. These findings suggest that there is important interplay between the endocrine and exocrine pancreas throughout life. This review summarizes the current knowledge on physiological and pathological changes in the exocrine and endocrine pancreas (i.e., beta-cell mass), and discusses the potential mechanisms of the interplay between the two compartments in humans to understand the pathophysiology of diabetes better.

Early pancreatic carcinogenesis - risk factors, early symptoms, and the impact of antidiabetic drugs

Risk factors (long-term diabetes, obesity) and early symptoms (new-onset diabetes, loss of weight, or persistent low body mass) are the initial symptoms of pancreatic carcinogenesis. They may be influenced by antidiabetic drugs and their correct evaluation is a prerequisite for early diagnosis of pancreatic cancer (PC). We review the risk factors, early symptoms, and the impact of antidiabetic drugs on early pancreatic carcinogenesis. The main source of data was the database Medline/PubMed and abstracts of international congresses (DDW, UEGW). The risk factors and early symptoms are integral components of the familial PC surveillance and sporadic PC screening. Preventive programs should always be include multistep and multidisciplinary procedures. The correct evaluation of antidiabetic drugs and their interactions with other components of pancreatic carcinogenesis may influence the early diagnosis of PC.

Effects of Obesity and Diabetes on α- and β-Cell Mass in Surgically Resected Human Pancreas

CONTEXT

The ethnic difference in β-cell regenerative capacity in response to obesity may be attributable to different phenotypes of type 2 diabetes among ethnicities.

OBJECTIVE

This study aimed to clarify the effects of diabetes and obesity on β- (BCM) and α-cell mass (ACM) in the Japanese population.

DESIGN, SETTING, AND PARTICIPANTS

We obtained the pancreases of 99 individuals who underwent pancreatic surgery and whose resected pancreas sample contained adequate normal pancreas for histological analysis. Questionnaires on a family history of diabetes and history of obesity were conducted in 59 patients. Pancreatic sections were stained for insulin or glucagon, and fractional β- and α-cell area were measured. Islet size and density as well as β-cell turnover were also quantified.

RESULTS

In patients with diabetes, BCM was decreased by 46% compared with age- and body mass index-matched nondiabetic patients (1.48% ± 1.08% vs 0.80% ± 0.54%, P < .001), whereas there was no difference in ACM between the groups. There was no effect of obesity or history of obesity on BCM and ACM irrespective of the presence or absence of diabetes. There was a negative correlation between BCM, but not ACM, and glycated hemoglobin before and after pancreatic surgery. In addition, reduced BCM was observed in patients with pancreatic cancer compared with those with other pancreatic tumors.

CONCLUSIONS

These findings suggest that the increase in BCM in the face of insulin resistance is extremely limited in the Japanese, and BCM rather than ACM has a major role in regulating blood glucose level in humans.

Pathogenesis of pancreatic cancer exosome-induced lipolysis in adipose tissue

BACKGROUND AND OBJECTIVES

New-onset diabetes and concomitant weight loss occurring several months before the clinical presentation of pancreatic cancer (PC) appear to be paraneoplastic phenomena caused by tumour-secreted products. Our recent findings have shown exosomal adrenomedullin (AM) is important in development of diabetes in PC. Adipose tissue lipolysis might explain early onset weight loss in PC. We hypothesise that lipolysis-inducing cargo is carried in exosomes shed by PC and is responsible for the paraneoplastic effects. Therefore, in this study we investigate if exosomes secreted by PC induce lipolysis in adipocytes and explore the role of AM in PC-exosomes as the mediator of this lipolysis.

DESIGN

Exosomes from patient-derived cell lines and from plasma of patients with PC and non-PC controls were isolated and characterised. Differentiated murine (3T3-L1) and human adipocytes were exposed to these exosomes to study lipolysis. Glycerol assay and western blotting were used to study lipolysis. Duolink Assay was used to study AM and adrenomedullin receptor (ADMR) interaction in adipocytes treated with exosomes.

RESULTS

In murine and human adipocytes, we found that both AM and PC-exosomes promoted lipolysis, which was abrogated by ADMR blockade. AM interacted with its receptor on the adipocytes, activated p38 and extracellular signal-regulated (ERK1/2) mitogen-activated protein kinases and promoted lipolysis by phosphorylating hormone-sensitive lipase. PKH67-labelled PC-exosomes were readily internalised into adipocytes and involved both caveolin and macropinocytosis as possible mechanisms for endocytosis.

CONCLUSIONS

PC-secreted exosomes induce lipolysis in subcutaneous adipose tissue; exosomal AM is a candidate mediator of this effect.

Adrenomedullin regulates intestinal physiology and pathophysiology

Adrenomedullin (AM) and proadrenomedullin N-terminal 20 peptide (PAMP) are 2 biologically active peptides produced by the same gene, ADM, with ubiquitous distribution and many physiological functions. Adrenomedullin is composed of 52 amino acids, has an internal molecular ring composed by 6 amino acids and a disulfide bond, and shares structural similarities with calcitonin gene-related peptide, amylin, and intermedin. The AM receptor consists of a 7-transmembrane domain protein called calcitonin receptor-like receptor in combination with a single transmembrane domain protein known as receptor activity-modifying protein. Using morphologic techniques, it has been shown that AM and PAMP are expressed throughout the gastrointestinal tract, being specially abundant in the neuroendocrine cells of the gastrointestinal mucosa; in the enterochromaffin-like and chief cells of the gastric fundus; and in the submucosa of the duodenum, ileum, and colon. This wide distribution in the gastrointestinal tract suggests that AM and PAMP may act as gut hormones regulating many physiological and pathologic conditions. To date, it has been proven that AM and PAMP act as autocrine/paracrine growth factors in the gastrointestinal epithelium, play key roles in the protection of gastric mucosa from various kinds of injury, and accelerate healing in diseases such as gastric ulcer and inflammatory bowel diseases. In addition, both peptides are potent inhibitors of gastric acid secretion and gastric emptying; they regulate the active transport of sugars in the intestine, regulate water and ion transport in the colon, modulate colonic bowel movements and small-intestine motility, improve endothelial barrier function, and stabilize circulatory function during gastrointestinal inflammation. Furthermore, AM and PAMP are antimicrobial peptides, and they contribute to the mucosal host defense system by regulating gut microbiota. To get a formal demonstration of the effects that endogenous AM and PAMP may have in gut microbiota, we developed an inducible knockout of the ADM gene. Using this model, we have shown, for the first time, that lack of AM/PAMP leads to changes in gut microbiota composition in mice. Further studies are needed to investigate whether this lack of AM/PAMP may have an impact in the development and/or progression of intestinal diseases through their effect on microbiota composition.

MYB Promotes Desmoplasia in Pancreatic Cancer through Direct Transcriptional Up-regulation and Cooperative Action of Sonic Hedgehog and Adrenomedullin

Extensive desmoplasia is a prominent pathological characteristic of pancreatic cancer (PC) that not only impacts tumor development, but therapeutic outcome as well. Recently, we demonstrated a novel role of MYB, an oncogenic transcription factor, in PC growth and metastasis. Here we studied its effect on pancreatic tumor histopathology and associated molecular and biological mechanisms. Tumor-xenografts derived from orthotopic-inoculation of MYB-overexpressing PC cells exhibited far-greater desmoplasia in histological analyses compared with those derived from MYB-silenced PC cells. These findings were further confirmed by immunostaining of tumor-xenograft sections with collagen-I, fibronectin (major extracellular-matrix proteins), and α-SMA (well-characterized marker of myofibroblasts or activated pancreatic stellate cells (PSCs)). Likewise, MYB-overexpressing PC cells provided significantly greater growth benefit to PSCs in a co-culture system as compared with the MYB-silenced cells. Interrogation of deep-sequencing data from MYB-overexpressing versus -silenced PC cells identified Sonic-hedgehog (SHH) and Adrenomedullin (ADM) as two differentially-expressed genes among others, which encode for secretory ligands involved in tumor-stromal cross-talk. In-silico analyses predicted putative MYB-binding sites in SHH and ADM promoters, which was later confirmed by chromatin-immunoprecipitation. A cooperative role of SHH and ADM in growth promotion of PSCs was confirmed in co-culture by using their specific-inhibitors and exogenous recombinant-proteins. Importantly, while SHH acted exclusively in a paracrine fashion on PSCs and influenced the growth of PC cells only indirectly, ADM could directly impact the growth of both PC cells and PSCs. In summary, we identified MYB as novel regulator of pancreatic tumor desmoplasia, which is suggestive of its diverse roles in PC pathobiology.

Altered profile of serum microRNAs in pancreatic cancer-associated new-onset diabetes mellitus

BACKGROUND

New-onset diabetes mellitus in pancreatic cancer has been recognized as a paraneoplastic phenomenon caused by the existence of the tumor. Circulating microRNAs (miRNAs) are emerging as non-invasive biomarkers for the detection of various cancers. In the present study, we hypothesized that a specific serum miRNA profile exists in pancreatic cancer-associated new-onset diabetes mellitus (PaC-DM).

METHODS

Initial screening of differentially expressed miRNAs in pooled serum samples from 25 PaC-DM patients, 25 non-cancer new-onset type 2 diabetes mellitus (T2DM) patients, and 25 healthy controls was performed by TaqMan low-density arrays (TLDA). A stem-loop quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was conducted to confirm the relative concentrations of candidate miRNAs in 80 PaC-DM, 85 non-cancer new-onset T2DM patients, and 80 healthy controls.

RESULTS

The TLDA identified 16 serum miRNAs that were significantly increased in PaC-DM samples. A combination of six serum miRNAs (miR-483-5p, miR-19a, miR-29a, miR-20a, miR-24, miR-25) was selected by qRT-PCR as a biomarker for PaC-DM. The area under the receiver operating characteristic curve (AUC) for the six-miRNA panel training and validation sets was 0.959 (95% confidence interval [CI] 0.890-1.028) and 0.902 (95% CI 0.844-0.955), respectively. The combination of these six miRNAs enabled the discrimination of PaC-DM from non-cancer new-onset T2DM with an AUC of 0.885 (95% CI 0.784-0.986) and 0.887 (95% CI 0.823-0.952) for the training and validation sets, respectively.

CONCLUSION

The six-serum miRNA panel may have potential as a biomarker for the accurate diagnosis and discrimination of PaC-DM from healthy controls and non-cancer new-onset T2DM.

Decreased Serum Thrombospondin-1 Levels in Pancreatic Cancer Patients Up to 24 Months Prior to Clinical Diagnosis: Association with Diabetes Mellitus

PURPOSE

Identification of serum biomarkers enabling earlier diagnosis of pancreatic ductal adenocarcinoma (PDAC) could improve outcome. Serum protein profiles in patients with preclinical disease and at diagnosis were investigated.

EXPERIMENTAL DESIGN

Serum from cases up to 4 years prior to PDAC diagnosis and controls (UKCTOCS,n= 174) were studied, alongside samples from patients diagnosed with PDAC, chronic pancreatitis, benign biliary disease, type 2 diabetes mellitus, and healthy subjects (n= 298). Isobaric tags for relative and absolute quantification (iTRAQ) enabled comparisons of pooled serum from a test set (n= 150). Validation was undertaken using multiple reaction monitoring (MRM) and/or Western blotting in all 472 human samples and samples from a KPC mouse model.

RESULTS

iTRAQ identified thrombospondin-1 (TSP-1) as reduced preclinically and in diagnosed samples. MRM confirmed significant reduction in levels of TSP-1 up to 24 months prior to diagnosis. A combination of TSP-1 and CA19-9 gave an AUC of 0.86, significantly outperforming both markers alone (0.69 and 0.77, respectively;P< 0.01). TSP-1 was also decreased in PDAC patients compared with healthy controls (P< 0.05) and patients with benign biliary obstruction (P< 0.01). Low levels of TSP-1 correlated with poorer survival, preclinically (P< 0.05) and at clinical diagnosis (P< 0.02). In PDAC patients, reduced TSP-1 levels were more frequently observed in those with confirmed diabetes mellitus (P< 0.01). Significantly lower levels were also observed in PDAC patients with diabetes compared with individuals with type 2 diabetes mellitus (P= 0.01).

CONCLUSIONS

Circulating TSP-1 levels decrease up to 24 months prior to diagnosis of PDAC and significantly enhance the diagnostic performance of CA19-9. The influence of diabetes mellitus on biomarker behavior should be considered in future studies.