Islet amyloid polypeptide in patients with pancreatic cancer and diabetes

Detection of protein oligomers with nanopores

Powerful single-molecule approaches have been developed for the accurate measurement of protein oligomers, but they are often low throughput and limited to the measurement of specific systems. To overcome this problem, nanopore-based detection holds the promise of providing the high throughput, broad applicability, and accuracy necessary to characterize protein oligomers in a variety of contexts. Nanopores provide accuracy comparable with that of state-of-the-art single-molecule detection methods, but with the added potential for fast and accurate measurements that may be amenable to industrial-scale manufacture. Key to enabling this expansion is combination with other emerging technologies such as DNA nanostructure tagging, machine learning-enabled signal analysis, and innovative detection device manufacture. Together, these technologies could enable widespread adoption of nanopore-based sensing in oligomer detection, revolutionizing diagnostics and biomarker detection in protein misfolding diseases.

Pancreatic endocrine and exocrine signaling and crosstalk in physiological and pathological status

The pancreas, an organ with dual functions, regulates blood glucose levels through the endocrine system by secreting hormones such as insulin and glucagon. It also aids digestion through the exocrine system by secreting digestive enzymes. Complex interactions and signaling mechanisms between the endocrine and exocrine functions of the pancreas play a crucial role in maintaining metabolic homeostasis and overall health. Compelling evidence indicates direct and indirect crosstalk between the endocrine and exocrine parts, influencing the development of diseases affecting both. From a developmental perspective, the exocrine and endocrine parts share the same origin-the "tip-trunk" domain. In certain circumstances, pancreatic exocrine cells may transdifferentiate into endocrine-like cells, such as insulin-secreting cells. Additionally, several pancreatic diseases, including pancreatic cancer, pancreatitis, and diabetes, exhibit potential relevance to both endocrine and exocrine functions. Endocrine cells may communicate with exocrine cells directly through cytokines or indirectly by regulating the immune microenvironment. This crosstalk affects the onset and progression of these diseases. This review summarizes the history and milestones of findings related to the exocrine and endocrine pancreas, their embryonic development, phenotypic transformations, signaling roles in health and disease, the endocrine-exocrine crosstalk from the perspective of diseases, and potential therapeutic targets. Elucidating the regulatory mechanisms of pancreatic endocrine and exocrine signaling and provide novel insights for the understanding and treatment of diseases.

Select Endocrine Disorders and Exosomes in Early PDAC Diagnosis

Disturbances in carbohydrate metabolism are suggested to be the early symptoms of pancreatic ductal adenocarcinoma (PDAC). The accumulated data suggests that endocrine function-related biomarkers may represent a breakthrough in the early detection of PDAC. Factors which may predispose one to the development of PDAC are insulin resistance and hyperinsulinemia. Elevated insulin levels induce the onset of carcinogenesis by altering the differentiation and function of islet cells through stimulating growth factors, including insulin-like growth factors (IGFs). Impaired β cell function, along with the impact of PDAC-released factors (e.g., adrenomedullin (ADM), IGF-1, and macrophage inhibitory factor (MIF) on pancreatic islets, may contribute to the induction of diabetes associated with PDAC. Recently, exosomes have attracted worldwide attention due to their role in varied features of cell function, particularly in cancer progression. Exosomes comprise of small extracellular vesicles produced by almost all cells. These vesicles contain a vast array of biomolecules, including proteins and microRNAs. Exosomes participate in cancer growth and promote angiogenesis. They promote tumorigenesis and metastasis, and are associated with the acquisition of cancer cells resistant to chemotherapy. Data have been accumulating recently on the role of exosomes in the rapid recognition, prognosis and potential therapy of pancreatic cancer.

Sorcin can trigger pancreatic cancer-associated new-onset diabetes through the secretion of inflammatory cytokines such as serpin E1 and CCL5

A rise in blood glucose is an early warning sign of underlying pancreatic cancer (PC) and may be an indicator of genetic events in PC progression. However, there is still a lack of mechanistic research on pancreatic cancer-associated new-onset diabetes (PCAND). In the present study, we identified a gene SRI, which possesses a SNP with the potential to distinguish PCAND and Type 2 diabetes mellitus (T2DM), by machine learning on the basis of the UK Biobank database. In vitro and in vivo, sorcin overexpression induced pancreatic β-cell dysfunction. Sorcin can form a positive feedback loop with STAT3 to increase the transcription of serpin E1 and CCL5, which may directly induce β-cell dysfunction. In 88 biopsies, the expression of sorcin was elevated in PC tissues, especially in PCAND samples. Furthermore, plasma serpin E1 levels are higher in peripheral blood samples from PCAND patients than in those from T2DM patients. In conclusion, sorcin may be the key driver in PCAND, and further study on the sorcin-STAT3-serpin E1/CCL5 signaling axis may help us better understand the pathogenesis of PCAND and identify potential biomarkers.

Therapeutic Strategies for Pancreatic-Cancer-Related Type 2 Diabetes Centered around Natural Products

Pancreatic ductal adenocarcinoma (PDAC), a highly malignant neoplasm, is classified as one of the most severe and devastating types of cancer. PDAC is a notable malignancy that exhibits a discouraging prognosis and a rising occurrence. The interplay between diabetes and pancreatic cancer exhibits a reciprocal causation. The identified metabolic disorder has been observed to possess noteworthy consequences on health outcomes, resulting in elevated rates of morbidity. The principal mechanisms involve the suppression of the immune system, the activation of pancreatic stellate cells (PSCs), and the onset of systemic metabolic disease caused by dysfunction of the islets. From this point forward, it is important to recognize that pancreatic-cancer-related diabetes (PCRD) has the ability to increase the likelihood of developing pancreatic cancer. This highlights the complex relationship that exists between these two physiological states. Therefore, we investigated into the complex domain of PSCs, elucidating their intricate signaling pathways and the profound influence of chemokines on their behavior and final outcome. In order to surmount the obstacle of drug resistance and eliminate PDAC, researchers have undertaken extensive efforts to explore and cultivate novel natural compounds of the next generation. Additional investigation is necessary in order to comprehensively comprehend the effect of PCRD-mediated apoptosis on the progression and onset of PDAC through the utilization of natural compounds. This study aims to examine the potential anticancer properties of natural compounds in individuals with diabetes who are undergoing chemotherapy, targeted therapy, or immunotherapy. It is anticipated that these compounds will exhibit increased potency and possess enhanced pharmacological benefits. According to our research findings, it is indicated that naturally derived chemical compounds hold potential in the development of PDAC therapies that are both safe and efficacious.

Glucose Regulation after Partial Pancreatectomy: A Comparison of Pancreaticoduodenectomy and Distal Pancreatectomy in the Short and Long Term

BACKGRUOUND

Long term quality of life is becoming increasingly crucial as survival following partial pancreatectomy rises. The purpose of this study was to investigate the difference in glucose dysregulation after pancreaticoduodenectomy (PD) or distal pancreatectomy (DP).

METHODS

In this prospective observational study from 2015 to 2018, 224 patients who underwent partial pancreatectomy were selected: 152 (67.9%) received PD and 72 (32.1%) received DP. Comprehensive assessment for glucose regulation, including a 75 g oral glucose tolerance test was conducted preoperatively, and 1, 12, and 52 weeks after surgery. Patients were further monitored up to 3 years to investigate development of new-onset diabetes mellitus (NODM) in patients without diabetes mellitus (DM) at baseline or worsening of glucose regulation (≥1% increase in glycosylated hemoglobin [HbA1c]) in those with preexisting DM.

RESULTS

The disposition index, an integrated measure of β-cell function, decreased 1 week after surgery in both groups, but it increased more than baseline level in the PD group while its decreased level was maintained in the DP group, resulting in a between-group difference at the 1-year examination (P<0.001). During follow-up, the DP group showed higher incidence of NODM and worsening of glucose regulation than the PD group with hazard ratio (HR) 4.29 (95% confidence interval [CI], 1.49 to 12.3) and HR 2.15 (95% CI, 1.09 to 4.24), respectively, in the multivariate analysis including dynamic glycemic excursion profile. In the DP procedure, distal DP and spleen preservation were associated with better glucose regulation. DP had a stronger association with glucose dysregulation than PD.

CONCLUSION

Proactive surveillance of glucose dysregulation is advised, particularly for patients who receive DP.

Diabetes Mellitus in Pancreatic Cancer: A Distinct Approach to Older Subjects with New-Onset Diabetes Mellitus

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is associated with a very poor prognosis, with near-identical incidence and mortality. According to the World Health Organization Globocan Database, the estimated number of new cases worldwide will rise by 70% between 2020 and 2040. There are no effective screening methods available so far, even for high-risk individuals. The prognosis of PDAC, even at its early stages, is still mostly unsatisfactory. Impaired glucose metabolism is present in about 3/4 of PDAC cases.

METHODS

Available literature on pancreatic cancer and diabetes mellitus was reviewed using a PubMed database. Data from a national oncology registry (on PDAC) and information from a registry of healthcare providers (on diabetes mellitus and a number of abdominal ultrasound investigations) were obtained.

RESULTS

New-onset diabetes mellitus in subjects older than 60 years should be an incentive for a prompt and detailed investigation to exclude PDAC. Type 2 diabetes mellitus, diabetes mellitus associated with chronic non-malignant diseases of the exocrine pancreas, and PDAC-associated type 3c diabetes mellitus are the most frequent types. Proper differentiation of particular types of new-onset diabetes mellitus is a starting point for a population-based program. An algorithm for subsequent steps of the workup was proposed.

CONCLUSIONS

The structured, well-differentiated, and elaborately designed approach to the elderly with a new onset of diabetes mellitus could improve the current situation in diagnostics and subsequent poor outcomes of therapy of PDAC.

Role of Pancreatic Tumour-Derived Exosomes and Their Cargo in Pancreatic Cancer-Related Diabetes

One of the most common and deadly types of pancreatic cancer (PC) is pancreatic ductal adenocarcinoma (PDAC), with most patients succumbing to the disease within one year of diagnosis. Current detection strategies do not address asymptomatic PC; therefore, patients are diagnosed at an advanced stage when curative treatment is often no longer possible. In order to detect PC in asymptomatic patients earlier, the risk factors that could serve as reliable markers need to be examined. Diabetic mellitus (DM) is a significant risk factor for this malignancy and can be both a cause and consequence of PC. Typically, DM caused by PC is known as new-onset, pancreatogenic, pancreoprivic, or pancreatic cancer-related diabetes (PCRD). Although PCRD is quite distinct from type 2 DM (T2DM), there are currently no biomarkers that differentiate PCRD from T2DM. To identify such biomarkers, a better understanding of the mechanisms mediating PCRD is essential. To this end, there has been a growing research interest in recent years to elucidate the role of tumour-derived exosomes and their cargo in the pathogenesis of PCRD. Exosomes derived from tumours can be recognized for their specificity because they reflect the characteristics of their parent cells and are important in intercellular communication. Their cargo consists of proteins, lipids, and nucleic acids, which can be transferred to and alter the behaviour of recipient cells. This review provides a concise overview of current knowledge regarding tumour-derived exosomes and their cargo in PCRD and discusses the potential areas worthy of further study.

Post-meal endogenous insulin secretion was significantly lower in head than in body/tail cancer of the pancreas

THE AIM

Pancreatic cancer, a rapidly progressive malignancy, is often diagnosed in patients with diabetes. The incidence of pancreatic cancer has risen dramatically over recent decades. Early diagnosis of this malignancy is generally difficult because the symptoms do not become apparent until the disease has progressed, generally leading to a poor outcome. To achieve earlier diagnosis, we analyzed the clinical characteristics of pancreatic cancer patients showing deterioration of plasma glucose levels while hospitalized.

METHOD

Thirty-six cases were divided into 2 groups;those diagnosed with diabetes more than a year prior to identification of pancreatic cancer and diabetes secondary to pancreatic cancer. These 2 groups were further subdivided according to the tumor site (head or body/tail), allowing analysis of 4 subgroups. Anthropometric measurements, laboratory values were determined.

RESULTS

Both groups with diabetes lost at least 4 kg and showed HbA1c deterioration of at least 1% within 5 months of the pancreatic cancer diagnosis. The post-meal elevation of serum C-peptide immunoreactivity (CPR) was significantly decreased in the group with cancer of the pancreatic head, and this was unrelated to tumor size.

CONCLUSION

Characteristically, pancreatic head cancer was associated with decreased endogenous insulin secretion as compared to body/tail cancer. J. Med. Invest. 70 : 350-354, August, 2023.

Increased alpha cell to beta cell ratio in patients with pancreatic cancer

The development of pancreatic cancer (PC) is associated with worsening of glucose tolerance. However, there is limited information about the effects of PC on islet morphology. The aim of this study was to elucidate changes in alpha and beta cell mass in patients with PC. We enrolled 30 autopsy cases with death due to PC (9 with diabetes; DM) and 31 age- and BMI-matched autopsy cases without PC (controls, 12 with DM). Tumor-free pancreatic sections were stained for insulin and glucagon, and fractional beta cell (BCA) and alpha cell area (ACA) were quantified. In addition, expression of de-differentiation markers, i.e., ALDH1A3 and UCN3, was qualitatively evaluated. The pancreas of subjects with PC showed atrophic and fibrotic changes. There was no significant difference in BCA in subjects with PC compared to controls (1.53 ± 1.26% vs. 0.95 ± 0.42%, p = 0.07). However, ACA and ACA to BCA ratio were significantly higher in subjects with PC compared to controls (2.48 ± 2.39% vs. 0.53 ± 0.26% and 1.94 ± 1.93 vs. 0.59 ± 0.26, respectively, both p < 0.001). Increased ACA to BCA ratio was observed in subjects with PC irrespective of the presence of DM. Qualitative evaluation of ALDH1A3 and UCN3 expression showed no significant difference between the groups. In conclusion, in subjects with PC, alpha to beta cell mass ratio is increased, which may contribute to the increased risk of worsening glucose metabolism. Further studies are warranted to elucidate the mechanisms of increased alpha to beta cell mass in patients with PC.

Risk Factors for Pancreatic Cancer in Patients with New-Onset Diabetes: A Systematic Review and Meta-Analysis

(1) Background: Patients with new-onset diabetes (NOD) are at risk of pancreatic ductal adenocarcinoma (PDAC), but the most relevant additional risk factors and clinical characteristics are not well established. (2) Objectives: To compare the risk for PDAC in NOD patients to persons without diabetes. Identify risk factors of PDAC among NOD patients. (3) Methods: Medline, Embase, and Google Scholar were last searched in June 2022 for observational studies on NOD patients and assessing risk factors for developing PDAC. Data were extracted, and Meta-Analysis was performed. Pooled effect sizes with 95% confidence intervals (CI) were estimated with DerSimonian & Laird random effects models. (4) Findings: Twenty-two studies were included, and 576,210 patients with NOD contributed to the analysis, of which 3560 had PDAC. PDAC cases were older than controls by 6.14 years (CI 3.64–8.65, 11 studies). The highest risk of PDAC involved a family history of PDAC (3.78, CI 2.03–7.05, 4 studies), pancreatitis (5.66, CI 2.75–11.66, 9 studies), cholecystitis (2.5, CI 1.4–4.45, 4 studies), weight loss (2.49, CI 1.47–4.22, 4 studies), and high/rapidly increasing glycemia (2.33, CI 1.85–2.95, 4 studies) leading to more insulin use (4.91, CI 1.62–14.86, 5 studies). Smoking (ES 1.20, CI 1.03–1.41, 9 studies) and alcohol (ES 1.23, CI 1.09–1.38, 9 studies) have a smaller effect. (5) Conclusion: Important risk factors for PDAC among NOD patients are age, family history, and gallstones/pancreatitis. Symptoms are weight loss and rapid increase in glycemia. The identified risk factors could be used to develop a diagnostic model to screen NOD patients.

Risk Factors for Pancreatic Cancer in Patients with New-Onset Diabetes: A Systematic Review and Meta-Analysis

(1) Background: Patients with new-onset diabetes (NOD) are at risk of pancreatic ductal adenocarcinoma (PDAC), but the most relevant additional risk factors and clinical characteristics are not well established. (2) Objectives: To compare the risk for PDAC in NOD patients to persons without diabetes. Identify risk factors of PDAC among NOD patients. (3) Methods: Medline, Embase, and Google Scholar were last searched in June 2022 for observational studies on NOD patients and assessing risk factors for developing PDAC. Data were extracted, and Meta-Analysis was performed. Pooled effect sizes with 95% confidence intervals (CI) were estimated with DerSimonian & Laird random effects models. (4) Findings: Twenty-two studies were included, and 576,210 patients with NOD contributed to the analysis, of which 3560 had PDAC. PDAC cases were older than controls by 6.14 years (CI 3.64–8.65, 11 studies). The highest risk of PDAC involved a family history of PDAC (3.78, CI 2.03–7.05, 4 studies), pancreatitis (5.66, CI 2.75–11.66, 9 studies), cholecystitis (2.5, CI 1.4–4.45, 4 studies), weight loss (2.49, CI 1.47–4.22, 4 studies), and high/rapidly increasing glycemia (2.33, CI 1.85–2.95, 4 studies) leading to more insulin use (4.91, CI 1.62–14.86, 5 studies). Smoking (ES 1.20, CI 1.03–1.41, 9 studies) and alcohol (ES 1.23, CI 1.09–1.38, 9 studies) have a smaller effect. (5) Conclusion: Important risk factors for PDAC among NOD patients are age, family history, and gallstones/pancreatitis. Symptoms are weight loss and rapid increase in glycemia. The identified risk factors could be used to develop a diagnostic model to screen NOD patients.

The impact of immunonutrition on pancreaticoduodenectomy outcomes

Background

Malnutrition is a significant risk factor for decreased survival in cancer patients undergoing a pancreaticoduodenectomy (PD). Our study aims to investigate the impact of immunonutrition on length of stay (LOS), infection rates, postoperative pancreatic fistula (POPF), and delayed gastric emptying (DGE).

Study design

This study retrospectively reviewed 344 patients who underwent PD between 2007 and 2018. Patients were on a regular diet or 5 days of preoperative immunonutrition. Statistical analyses were done via t-test and chi-square test with a significance cutoff of p < 0.05.

Results

Immunonutrition was associated with increased intraabdominal infection (13% vs. 23%, p = 0.021), POPF (6% vs. 19%, p = 0.001), and decreased DGE (17% vs. 8%, p = 0.013). When patients were stratified by pathology, immunonutrition was not associated with POPF or infection rates in the pancreatic adenocarcinoma (PDAC) group. In the non-PDAC group, immunonutrition was associated with longer LOS (12.4 vs. 9.9 days, p = 0.02) and higher rates of intraabdominal infection (26% vs. 10%, p = 0.02) compared to the regular diet group.

Conclusion

In PDAC patients undergoing PD, preoperative immunonutrition did not have an impact on LOS, infections, POPF, or DGE. In non-PDAC patients, immunonutrition was associated with longer LOS and higher intraabdominal infections. Additional studies are needed to validate the routine use of immunonutrition in this patient population.

Construction of immune-related signature and identification of S100A14 determining immune-suppressive microenvironment in pancreatic cancer

Pancreatic cancer (PC) is a highly lethal and aggressive disease with its incidence and mortality quite discouraging. A robust prognostic signature and novel biomarkers are urgently needed for accurate stratification of the patients and optimization of clinical decision-making. Since the critical role of immune microenvironment in the progression of PC, a prognostic signature based on seven immune-related genes was established, which was validated in The Cancer Genome Atlas (TCGA) training set, TCGA testing set, TCGA entire set and GSE71729 set. Furthermore, S100A14 (S100 Calcium Binding Protein A14) was identified as the gene occupying the most paramount position in risk signature. According to the GSEA, CIBERSORT and ESTIMATE algorithm, S100A14 was mainly associated with lower proportion of CD8 + T cells and higher proportion of M0 macrophages in PC tissue. Meanwhile, analysis of single-cell dataset CRA001160 revealed a significant negative correlation between S100A14 expression in PC cells and CD8 + T cell infiltration, which was further confirmed by tissue microenvironment landscape imaging and machine learning-based analysis in our own PUMCH cohort. Additionally, analysis of a pan-pancreatic cancer cell line illustrated that S100A14 might inhibit CD8 + T cell activation via the upregulation of PD-L1 expression in PC cells, which was also verified by the immunohistochemical results of PUMCH cohort. Finally, tumor mutation burden analysis and immunophenoscore algorithm revealed that patients with high S100A14 expression had a higher probability of responding to immunotherapy. In conclusion, our study established an efficient immune-related prediction model and identified the potential role of S100A14 in regulating the immune microenvironment and serving as a biomarker for immunotherapy efficacy prediction.

Role of Pancreatic Stellate Cell-Derived Exosomes in Pancreatic Cancer-Related Diabetes: A Novel Hypothesis

Pancreatic ductal adenocarcinoma (PDAC) is a devastating condition characterised by vague symptomatology and delayed diagnosis. About 30% of PDAC patients report a history of new onset diabetes, usually diagnosed within 3 years prior to the diagnosis of cancer. Thus, new onset diabetes, which is also known as pancreatic cancer-related diabetes (PCRD), could be a harbinger of PDAC. Diabetes is driven by progressive β cell loss/dysfunction and insulin resistance, two key features that are also found in PCRD. Experimental studies suggest that PDAC cell-derived exosomes carry factors that are detrimental to β cell function and insulin sensitivity. However, the role of stromal cells, particularly pancreatic stellate cells (PSCs), in the pathogenesis of PCRD is not known. PSCs are present around the earliest neoplastic lesions and around islets. Given that PSCs interact closely with cancer cells to drive cancer progression, it is possible that exosomal cargo from both cancer cells and PSCs plays a role in modulating β cell function and peripheral insulin resistance. Identification of such mediators may help elucidate the mechanisms of PCRD and aid early detection of PDAC. This paper discusses the concept of a novel role of PSCs in the pathogenesis of PCRD.

REPRINT OF: CLASSIFICATION OF DIABETES MELLITUS

Executive Summary This document updates the 1999 World Health Organization (WHO) classification of diabetes. It prioritizes clinical care and guides health professionals in choosing appropriate treatments at the time of diabetes diagnosis, and provides practical guidance to clinicians in assigning a type of diabetes to individuals at the time of diagnosis. It is a compromise between clinical and aetiological classification because there remain gaps in knowledge of the aetiology and pathophysiology of diabetes. While acknowledging the progress that is being made towards a more precise categorization of diabetes subtypes, the aim of this document is to recommend a classification that is feasible to implement in different settings throughout the world. The revised classification is presented in Table 1. Unlike the previous classification, this classification does not recognize subtypes of type 1 diabetes and type 2 diabetes and includes new types of diabetes ("hybrid types of diabetes" and "unclassified diabetes").

Hyperglycemia as a risk factor in pancreatic cancer: A nested case-control study using prediagnostic blood glucose levels

OBJECTIVE

To determine the risk association between fasting glucose levels and pancreatic cancer using systematically collected prediagnostic blood glucose samples.

METHODS

Prospective nested case-control study of participants from the Northern Sweden Health and Disease Study, including 182 cases that developed pancreatic cancer and four matched controls per case. Blood glucose levels collected up to 24 years before pancreatic cancer diagnosis were analyzed. The association between fasting glucose levels and pancreatic cancer risk was determined using unconditional and conditional logistic regression models. The association between fasting glucose and the time to pancreatic cancer diagnosis, tumor stage and survival was determined using likelihood-ratio test, t-test and log rank test.

RESULTS

The unadjusted risk of developing pancreatic cancer increased with increasing fasting glucose levels (OR 1.30, 95% CI 1.05-1.60, P = .015). Impaired fasting glucose (≥6.1 mmol/L) was associated with an adjusted risk of 1.77 for developing pancreatic cancer (95% CI 1.05-2.99, P = .032). In subgroup analysis, fasting glucose levels were associated with an increased risk in never-smokers (OR 4.02, 95% CI 1.26-12.77, P = .018) and non-diabetics (OR 3.08, 95% CI 1.08-8.79, P = .035) (non-significant for interaction). The ratio between fasting glucose and BMI was higher among future pancreatic cancer patients and an increased ratio was associated with elevated risk of pancreatic cancer (OR 1.66, 95% CI 1.04-2.66, P = .034). Fasting glucose levels were not associated with TNM stage at diagnosis or survival.

CONCLUSIONS

High fasting glucose is associated with an increased risk of being diagnosed with pancreatic cancer.

Pancreatic cancer cachexia: three dimensions of a complex syndrome

Cancer cachexia is a multifactorial syndrome that is characterised by a loss of skeletal muscle mass, is commonly associated with adipose tissue wasting and malaise, and responds poorly to therapeutic interventions. Although cachexia can affect patients who are severely ill with various malignant or non-malignant conditions, it is particularly common among patients with pancreatic cancer. Pancreatic cancer often leads to the development of cachexia through a combination of distinct factors, which, together, explain its high prevalence and clinical importance in this disease: systemic factors, including metabolic changes and pathogenic signals related to the tumour biology of pancreatic adenocarcinoma; factors resulting from the disruption of the digestive and endocrine functions of the pancreas; and factors related to the close anatomical and functional connection of the pancreas with the gut. In this review, we conceptualise the various insights into the mechanisms underlying pancreatic cancer cachexia according to these three dimensions to expose its particular complexity and the challenges that face clinicians in trying to devise therapeutic interventions.

Relationship Between Remnant Pancreatic Volume and Endocrine Function After Pancreaticoduodenectomy

BACKGROUND

Decreased pancreatic volume (PV) is a predictive factor for diabetes mellitus (DM) after surgery. There are few reports on PV and endocrine function pre- and post-surgery. We investigated the correlation between PV and insulin secretion.

METHODS

Seventeen patients underwent pancreaticoduodenectomy (PD) Pre- and post-surgery PV and C-peptide index (CPI) measurements were performed. Additionally, the correlation between PV and CPI was analyzed.

RESULTS

The mean preoperative PV (PPV) was 55.1 ± 31.6 mL, postoperative remnant PV (RPV) was 25.3±17.3 mL, and PV reduction was 53%. The mean preoperative C-peptide immunoreactivity (CPR) was 1.39 ± .51 and postoperative CPR was .85±.51. The mean preoperative CPI was 1.29±.72 and postoperative CPI was .73 ± .48. Significant correlations were observed between RPV and post CPR (ρ = .507, P = .03) and post CPI (ρ = .619, P = .008).

DISCUSSION

There was a significant correlation between RPV and CPI after PD. A smaller RPV resulted in lower insulin secretion ability, increasing the potential risk of new-onset DM after PD.

Screening Strategy of Pancreatic Cancer in Patients with Diabetes Mellitus

The incidence of pancreatic cancer (PCa) is increasing worldwide and has become one of the leading causes of cancer-related death. Screening for high risk populations is fundamental to overcome this intractable malignancy. Diabetes mellitus (DM) is classically known as a risk factor for PCa. Recently the reverse causality is in the spotlight, that is to say, DM is considered to be a manifestation of PCa. Numbers of epidemiological studies clarified that new-onset DM (≤2-year duration) was predominant in PCa patients and the relative risk for PCa inversely correlated with duration of DM. Among patients with new-onset DM, elder onset, weight loss, and rapid exacerbation of glycemic control were reported to be promising risk factors and signs, and the model was developed by combining these factors. Several pilot studies disclosed the possible utility of biomarkers to discriminate PCa-associated DM from type 2 DM. However, there is no reliable biomarkers to be used in the practice. We previously reported the application of a multivariate index for PCa based on the profile of plasma free amino acids (PFAAs) among diabetic patients. We are further investigating on the PFAA profile of PCa-associated DM, and it can be useful for developing the novel biomarker in the near future.

Understanding pancreatic exocrine insufficiency and replacement therapy in pancreatic cancer

Pancreatic exocrine insufficiency (PEI) is highly prevalent in patients with pancreatic cancer, and has substantial implications for quality of life and survival. Post resection, PEI is associated with increased post-operative complications, longer hospital stays and higher costs. Treatment with pancreatic enzyme replacement therapy (PERT) improves quality of life and confers significant survival advantages. Despite this many patients with pancreatic cancer do not currently receive PERT. The nutritional consequences of PEI are extensive and even more relevant in the elderly owing to age related gastrointestinal tract and pancreatic changes that predispose to malnutrition.

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.

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.

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.

The Warburg effect in human pancreatic cancer cells triggers cachexia in athymic mice carrying the cancer cells

Background

Cancer cachexia is a cancer-induced metabolic disorder and a major cause of cancer-induced death. The constituents of cancer cachexia include an increase in energy expenditure, hepatic gluconeogenesis, fat lipolysis, and skeletal-muscle proteolysis and a decrease in body weight. The aetiology of cancer cachexia is unclear and may involve cancer-cell metabolism and secretion. In this study, we investigated whether the high glycolysis in cancer cells (the Warburg effect) triggers cachexia in athymic mice carrying pancreatic cancer cells.

Methods

First, we examined five human pancreatic cancer cell lines for glycolysis and cachectic-cytokine secretion. Consequently, MiaPaCa2 and AsPC1 cells were selected for the present study, because the glycolysis in MiaPaCa2 cells was typically high and that in AsPC1 cells was exceptionally low. In addition, both MiaPaCa2 and AsPC1 cells were competent in the secretion of examined cytokines. Next, we transplanted MiaPaCa2 and AsPC1 cells subcutaneously in different athymic mice for 8 weeks, using intact athymic mice for control. In another experiment, we treated normal mice with the supernatants of MiaPaCa2 or AsPC1 cells for 7 days, using vehicle-treated mice for control. In both models, we measured food intake and body weight, assayed plasma glucose, triglycerides, and TNF-α and used Western blot to determine the proteins that regulated hepatic gluconeogenesis, fat lipolysis, and skeletal-muscle proteolysis in the corresponding tissues. We also studied the effect of MiaPaCa2-cell supernatants on the proteolysis of C2C12 skeletal-muscle cells in vitro.

Results

The athymic mice carrying high-glycolytic MiaPaCa2 cells had anorexia and also showed evidence for cachexia, including increased hepatic gluconeogenesis, fat lipolysis and skeletal-muscle proteolysis and decreased body weight. The athymic mice carrying low-glycolytic AsPC1 cells had anorexia but did not show the above-mentioned evidence for cachexia. When normal mice were treated with the supernatants of MiaPaCa2 or AsPC1 cells, their energy homeostasis was largely normal. Thus, the cachexia in the athymic mice carrying MiaPaCa2 cells may not result from humeral factors released by the cancer cells. In vitro, MiaPaCa2-cell supernatants did not induce proteolysis in C2C12 cells.

Conclusion

The Warburg effect in pancreatic cancer cells is an independent aetiological factor for pancreatic cancer-induced cachexia.

Expression profiles of stress-related genes in islets from donors with progressively impaired glucose metabolism

It is currently unknown how the islet transcriptional pattern changes as glucose metabolism deteriorates and progresses to fulminant type 2 diabetes (T2D). In this study, we hypothesized that islets from donors with elevated HbA1c levels, but not yet diagnosed with T2D, would show signs of cell stress on a transcriptional level. Laser capture microdissection and qPCR arrays including 330 genes related to mitochondria, oxidative stress, or the unfolded protein response were used to extract and analyze islets from organ donors with HbA1c <5.5% (37 mmol/mol), elevated HbA1c (6.0-6.5% (42-48 mmol/mol)), high HbA1c (>6.5% (48 mmol/mol)) or established T2D. Principal component analysis and hierarchical clustering based on the expression of all 330 genes displayed no obvious separation of the four different donor groups, indicating that the inter-donor variations were larger than the differences between groups. However, 44 genes were differentially expressed (P < 0.05, false discovery rate <30%) between islets from donors with HbA1c <5.5% (37 mmol/mol) compared with islets from T2D subjects. Twelve genes were differentially expressed compared to control islets in both donors with established T2D and donors with elevated HbA1c (6.0-6.5% (42-48 mmol/mol)). Overexpressed genes were related mainly to the unfolded protein response, whereas underexpressed genes were related to mitochondria. Our data on transcriptional changes in human islets retrieved by LCM from high-quality biopsies, as pre-diabetes progresses to established T2D, increase our understanding on how islet stress contributes to the disease development.

Systems biology of the IMIDIA biobank from organ donors and pancreatectomised patients defines a novel transcriptomic signature of islets from individuals with type 2 diabetes

AIMS/HYPOTHESIS

Pancreatic islet beta cell failure causes type 2 diabetes in humans. To identify transcriptomic changes in type 2 diabetic islets, the Innovative Medicines Initiative for Diabetes: Improving beta-cell function and identification of diagnostic biomarkers for treatment monitoring in Diabetes (IMIDIA) consortium ( www.imidia.org ) established a comprehensive, unique multicentre biobank of human islets and pancreas tissues from organ donors and metabolically phenotyped pancreatectomised patients (PPP).

METHODS

Affymetrix microarrays were used to assess the islet transcriptome of islets isolated either by enzymatic digestion from 103 organ donors (OD), including 84 non-diabetic and 19 type 2 diabetic individuals, or by laser capture microdissection (LCM) from surgical specimens of 103 PPP, including 32 non-diabetic, 36 with type 2 diabetes, 15 with impaired glucose tolerance (IGT) and 20 with recent-onset diabetes (<1 year), conceivably secondary to the pancreatic disorder leading to surgery (type 3c diabetes). Bioinformatics tools were used to (1) compare the islet transcriptome of type 2 diabetic vs non-diabetic OD and PPP as well as vs IGT and type 3c diabetes within the PPP group; and (2) identify transcription factors driving gene co-expression modules correlated with insulin secretion ex vivo and glucose tolerance in vivo. Selected genes of interest were validated for their expression and function in beta cells.

RESULTS

Comparative transcriptomic analysis identified 19 genes differentially expressed (false discovery rate ≤0.05, fold change ≥1.5) in type 2 diabetic vs non-diabetic islets from OD and PPP. Nine out of these 19 dysregulated genes were not previously reported to be dysregulated in type 2 diabetic islets. Signature genes included TMEM37, which inhibited Ca²⁺-influx and insulin secretion in beta cells, and ARG2 and PPP1R1A, which promoted insulin secretion. Systems biology approaches identified HNF1A, PDX1 and REST as drivers of gene co-expression modules correlated with impaired insulin secretion or glucose tolerance, and 14 out of 19 differentially expressed type 2 diabetic islet signature genes were enriched in these modules. None of these signature genes was significantly dysregulated in islets of PPP with impaired glucose tolerance or type 3c diabetes.

CONCLUSIONS/INTERPRETATION

These studies enabled the stringent definition of a novel transcriptomic signature of type 2 diabetic islets, regardless of islet source and isolation procedure. Lack of this signature in islets from PPP with IGT or type 3c diabetes indicates differences possibly due to peculiarities of these hyperglycaemic conditions and/or a role for duration and severity of hyperglycaemia. Alternatively, these transcriptomic changes capture, but may not precede, beta cell failure.

The impact of pancreaticoduodenectomy on endocrine and exocrine pancreatic function: A prospective cohort study based on pre- and postoperative function tests

BACKGROUND/OBJECTIVES

Studies reporting on function after pancreatic surgery are frequently based on diabetes history, fasting glycemia or random glycemia. The aim of this study was to investigate prospectively the evolution of pancreatic function in patients undergoing pancreaticoduodenectomy based on proper pre- and postoperative function tests. It was hypothesised that pancreatic function deteriorates after pancreaticoduodenectomy.

METHODS

Between 2013 and 2016, 78 patients undergoing pancreaticoduodenectomy for oncologic indications had a prospective evaluation of their endocrine and exocrine pancreatic function. Endocrine function was evaluated with the 75 g oral glucose tolerance test (OGTT) and the 1 mg intravenous glucagon test. Exocrine function was evaluated with a 13C-labelled mixed-triglyceride breath test. Tests were performed pre- and postoperatively.

RESULTS

In 90.5% (19/21) of patients with preoperatively known diabetes, no change in endocrine function was observed. In contrast, endocrine function improved in 68.1% (15/22) of patients with newly diagnosed diabetes. 40% (14/35) of patients with a preoperative normal OGTT or prediabetes experienced deterioration in function. In multivariate analysis, improvement of newly diagnosed diabetes was correlated with preoperative bilirubin levels (p = 0.045), while progression towards diabetes was correlated with preoperative C-peptidogenic index T₃₀ (p = 0.037). A total of 20.5% (16/78) of patients had pancreatic exocrine insufficiency preoperatively. Another 51.3% (40/78) of patients deteriorated on exocrine level. In total, 64.1% (50/78) of patients required pancreatic enzyme-replacement therapy postoperatively.

CONCLUSIONS

Although deterioration of endocrine function was expected after pancreatic resection, improvement is frequently observed in patients with newly diagnosed diabetes. Exocrine function deteriorates after pancreaticoduodenectomy.

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.

An unusual presentation of a benign pancreatic lesion containing amyloid

We present a unique case of a benign pancreatic lesion which was positive for amyloid in a 55-year-old female patient without systemic amyloidosis. Further testing revealed islet-type amyloid polypeptide (or amylin), a protein found in various diseases such as diabetes, insulinoma and pancreatic adenocarcinoma-none of which was seen in our patient.

Pancreatic Exocrine Insufficiency in Pancreatic Cancer

Abstract: Cancer patients experience weight loss for a variety of reasons, commencing with the tumor’s metabolism (Warburg effect) and proceeding via cachexia to loss of appetite. In pancreatic cancer, several other factors are involved, including a loss of appetite with a particular aversion to meat and the incapacity of the pancreatic gland to function normally when a tumor is present in the pancreatic head. Pancreatic exocrine insufficiency is characterized by a deficiency of the enzymes secreted from the pancreas due to the obstructive tumor, resulting in maldigestion. This, in turn, contributes to malnutrition, specifically a lack of fat-soluble vitamins, antioxidants, and other micronutrients. Patients with pancreatic cancer and pancreatic exocrine insufficiency have, overall, an extremely poor prognosis with regard to surgical outcome and overall survival. Therefore, it is crucial to be aware of the mechanisms involved in the disease, to be able to diagnose pancreatic exocrine insufficiency early on, and to treat malnutrition appropriately, for example, with pancreatic enzymes.

Much More than Trousseau Syndrome. The Broad Spectrum of the Pancreatic Paraneoplastic Syndromes

When 150 years ago Armand Trousseau proposed that some thrombotic events might be the first sign of concealed visceral malignancies, these findings seemed to be just of anecdotal interest. Since then, however, we have learned that adenocarcinomas, including pancreatic cancers could be associated with a wide spectrum of paraneoplastic syndromes. They may precede the detection of the tumor, may occur simultaneously or may develop during its progression. Due to various hematologic, endocrine, cutaneous, articular, neuromuscular, renal or even psychiatric syndromes, their correct interpretation is intriguing, and because their early signs are not necessarily recognized first by oncologists, the paraneoplastic syndromes pose a diagnostic challenge. Unfortunately, we cannot generalize about their mechanisms, because the molecular backgrounds are far-reaching. In most of the cases, the pancreatic cancer cells release various factors into the bloodstream triggering the coagulation cascade. These patients frequently present with venous thromboembolism, and sometimes they are resistant to anticoagulation. The simultaneous thrombotic and bleeding evens do reflect the abnormal hemostasis. In other instances autoantibodies are formed against cutaneous, renal, neuromuscular or nervous tissues, but the mechanism of some syndromes remains unclear. Clinicians should be aware that pancreatic carcinoma may be associated with not just the Trousseau-syndrome.

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.

Metabolic Syndrome, Type 2 Diabetes, and Cancer: Epidemiology and Potential Mechanisms

Obesity is associated with multiple metabolic disorders that drive cardiovascular disease, T2D and cancer. The doubling in the number of obese adults over the past 3 decades led to the recognition of obesity as a "disease". With over 42 million children obese or overweight, this epidemic is rapidly growing worldwide. Obesity and T2D are both associated together and independently with an increased risk for cancer and a worse prognosis. Accumulating evidence from epidemiological studies revealed potential factors that may explain the association between obesity-linked metabolic disorders and cancer risk. Studies based on the insulin resistance MKR mice, highlighted the roe of the insulin receptor and its downstream signaling proteins in mediating hyperinsulinemia's mitogenic effects. Hypercholesterolemia was also shown to promote the formation of larger tumors and enhancement in metastasis. Furthermore, the conversion of cholesterol into 27-Hydroxycholesterol was found to link high fat diet-induced hypercholesterolemia with cancer pathophysiology. Alteration in circulating adipokines and cytokines are commonly found in obesity and T2D. Adipokines are involved in tumor growth through multiple mechanisms including mTOR, VEGF and cyclins. In addition, adipose tissues are known to recruit and alter macrophage phenotype; these macrophages can promote cancer progression by secreting inflammatory cytokines such as TNF-α and IL-6. Better characterization on the above factors and their downstream effects is required in order to translate the current knowledge into the clinic, but more importantly is to understand which are the key factors that drive cancer in each patient. Until we reach this point, policies and activities toward healthy diets and physical activities remain the best medicine.

Pancreatic Cancer-Derived Exosomes Cause Paraneoplastic β-cell Dysfunction

PURPOSE

Pancreatic cancer frequently causes diabetes. We recently proposed adrenomedullin as a candidate mediator of pancreatic β-cell dysfunction in pancreatic cancer. How pancreatic cancer-derived adrenomedullin reaches β cells remote from the cancer to induce β-cell dysfunction is unknown. We tested a novel hypothesis that pancreatic cancer sheds adrenomedullin-containing exosomes into circulation, which are transported to β cells and impair insulin secretion.

EXPERIMENTAL METHODS

We characterized exosomes from conditioned media of pancreatic cancer cell lines (n = 5) and portal/peripheral venous blood of patients with pancreatic cancer (n = 20). Western blot analysis showed the presence of adrenomedullin in pancreatic cancer-exosomes. We determined the effect of adrenomedullin-containing pancreatic cancer exosomes on insulin secretion from INS-1 β cells and human islets, and demonstrated the mechanism of exosome internalization into β cells. We studied the interaction between β-cell adrenomedullin receptors and adrenomedullin present in pancreatic cancer-exosomes. In addition, the effect of adrenomedullin on endoplasmic reticulum (ER) stress response genes and reactive oxygen/nitrogen species generation in β cells was shown.

RESULTS

Exosomes were found to be the predominant extracellular vesicles secreted by pancreatic cancer into culture media and patient plasma. Pancreatic cancer-exosomes contained adrenomedullin and CA19-9, readily entered β cells through caveolin-mediated endocytosis or macropinocytosis, and inhibited insulin secretion. Adrenomedullin in pancreatic cancer exosomes interacted with its receptor on β cells. Adrenomedullin receptor blockade abrogated the inhibitory effect of exosomes on insulin secretion. β cells exposed to adrenomedullin or pancreatic cancer exosomes showed upregulation of ER stress genes and increased reactive oxygen/nitrogen species.

CONCLUSIONS

Pancreatic cancer causes paraneoplastic β-cell dysfunction by shedding adrenomedullin(+)/CA19-9(+) exosomes into circulation that inhibit insulin secretion, likely through adrenomedullin-induced ER stress and failure of the unfolded protein response.

The early diagnosis of pancreatic cancer and diabetes: what's the relationship?

Pancreatic cancer (PC) has a dismal prognosis as cancer-specific symptoms occur only at an advanced stage. If the cancer is to be discovered early, it will have to be done in asymptomatic individuals. Since the incidence of PC is low, screening for asymptomatic cancer in the general population will not be feasible. Screening will have to be restricted to subjects at high risk for PC. The proportion of PC patients who also have hyperglycemia or diabetes has previously been under appreciated; new data show that up to 80% are either hyperglycemic or diabetic and this can be evident in the pre-symptomatic phase. Diabetes improves following PC resection suggesting that diabetes is caused by the cancer. Conversely, older subjects with new-onset diabetes have an approximately eight fold higher risk of having PC compared to the general population. Recognition of new-onset diabetes as an early manifestation of PC could lead to diagnosis of asymptomatic, early stage PC. However, primary type 2 diabetes is common and PC is relatively uncommon in the general population and the two forms of diabetes are clinically indistinguishable. The success of the strategy to use new-onset hyperglycemia and diabetes as a screening tool to identify subjects with a high likelihood of having asymptomatic PC will depend largely on our ability to differentiate PC-associated diabetes from the more common type 2 diabetes using a (serologic) biomarker.

Diabetes, pancreatic cancer, and metformin therapy

Pancreatic cancer carries a poor prognosis as most patients present with advanced disease and preferred chemotherapy regimens offer only modest effects on survival. Risk factors include smoking, obesity, heavy alcohol, and chronic pancreatitis. Pancreatic cancer has a complex relationship with diabetes, as diabetes can be both a risk factor for pancreatic cancer and a result of pancreatic cancer. Insulin, insulin-like growth factor-1 (IGF-1), and certain hormones play an important role in promoting neoplasia in diabetics. Metformin appears to reduce risk for pancreatic cancer and improve survival in diabetics with pancreatic cancer primarily by decreasing insulin/IGF signaling, disrupting mitochondrial respiration, and inhibiting the mammalian target of rapamycin (mTOR) pathway. Other potential anti-tumorigenic effects of metformin include the ability to downregulate specificity protein transcription factors and associated genes, alter microRNAs, decrease cancer stem cell proliferation, and reduce DNA damage and inflammation. Here, we review the most recent knowledge on risk factors and treatment of pancreatic cancer and the relationship between diabetes, pancreatic cancer, and metformin as a potential therapy.

Pancreatic Cancer-Derived Exosomes Cause Paraneoplastic β-cell Dysfunction

PURPOSE

Pancreatic cancer frequently causes diabetes. We recently proposed adrenomedullin as a candidate mediator of pancreatic β-cell dysfunction in pancreatic cancer. How pancreatic cancer-derived adrenomedullin reaches β cells remote from the cancer to induce β-cell dysfunction is unknown. We tested a novel hypothesis that pancreatic cancer sheds adrenomedullin-containing exosomes into circulation, which are transported to β cells and impair insulin secretion.

EXPERIMENTAL METHODS

We characterized exosomes from conditioned media of pancreatic cancer cell lines (n = 5) and portal/peripheral venous blood of patients with pancreatic cancer (n = 20). Western blot analysis showed the presence of adrenomedullin in pancreatic cancer-exosomes. We determined the effect of adrenomedullin-containing pancreatic cancer exosomes on insulin secretion from INS-1 β cells and human islets, and demonstrated the mechanism of exosome internalization into β cells. We studied the interaction between β-cell adrenomedullin receptors and adrenomedullin present in pancreatic cancer-exosomes. In addition, the effect of adrenomedullin on endoplasmic reticulum (ER) stress response genes and reactive oxygen/nitrogen species generation in β cells was shown.

RESULTS

Exosomes were found to be the predominant extracellular vesicles secreted by pancreatic cancer into culture media and patient plasma. Pancreatic cancer-exosomes contained adrenomedullin and CA19-9, readily entered β cells through caveolin-mediated endocytosis or macropinocytosis, and inhibited insulin secretion. Adrenomedullin in pancreatic cancer exosomes interacted with its receptor on β cells. Adrenomedullin receptor blockade abrogated the inhibitory effect of exosomes on insulin secretion. β cells exposed to adrenomedullin or pancreatic cancer exosomes showed upregulation of ER stress genes and increased reactive oxygen/nitrogen species.

CONCLUSIONS

Pancreatic cancer causes paraneoplastic β-cell dysfunction by shedding adrenomedullin(+)/CA19-9(+) exosomes into circulation that inhibit insulin secretion, likely through adrenomedullin-induced ER stress and failure of the unfolded protein response.

Clinical signature and pathogenetic factors of diabetes associated with pancreas disease (T3cDM): a prospective observational study in surgical patients

To characterize the clinical signature and etiopathogenetic factors of diabetes associated with pancreas disease [type 3 diabetes mellitus (T3cDM)]. To estimate incidence and identify predictors of both diabetes onset and remission after pancreatic surgery. A prospective observational study was conducted. From January 2008 to December 2012, patients (n = 651) with new diagnosis of pancreatic disease admitted to the Pancreatic Surgery Unit of the San Raffaele Scientific Institute were evaluated. 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. At baseline, the prevalence of diabetes was 38 % (age of onset 64 ± 11 years). In most cases, diabetes occurred within 48 months from pancreatic disease diagnosis. Among different pancreatic diseases, minor differences were observed in diabetes characteristics, with the exception of the prevalence. Diabetes appeared associated with classical risk factors for type 2 diabetes (i.e., age, sex, family history of diabetes and body mass index), and both beta-cell dysfunction and insulin resistance appeared relevant determinants. The prevalence of adult-onset autoimmune diabetes was as previously reported within type 2 diabetes. Within a few days after surgery, either diabetes remission or new-onset diabetes was observed. In patients with pancreatic cancer, no difference in diabetes remission was observed after palliative or resective surgery. Classical risk factors for type 2 diabetes were associated with the onset of diabetes after surgery. T3cDM appeared as a heterogeneous entity strongly overlapped with type 2 diabetes.

Association of diabetes mellitus and pancreatic adenocarcinoma: a meta-analysis of 88 studies

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is often diagnosed at an advanced, incurable stage. Previous epidemiological data suggests that diabetes mellitus (DM) is a risk factor for PDAC, which may be important in early detection. However, the strength of this association needs to be determined, taking into account a number of recently published studies.

METHODS

A systematic review of the association between DM and PDAC was undertaken by searching electronic databases and journal references from 1973 to 2013. Summary estimates were obtained separately for case-control and cohort studies by means of a 'random effects' approach. Data pertaining to the DM was recorded and plotted at both an individual and study level, with the relative risks (RR) pooled separately to determine the relationship of DM duration and PDAC.

RESULTS

A total of 88 independent studies, including 50 cohort and 39 case-control studies were examined. The overall summary-combined RR was 1.97 (95 % CI 1.78-2.18) with marked heterogeneity that could not be clearly attributed to any subgroup analyses. The risk of PDAC was greatest early after the diagnosis of DM but remained elevated long after the diagnosis. The individual-level RR ranged from 6.69 at less than 1 year to 1.36 at 10 years.

CONCLUSION

The results demonstrate a strong association between PDAC and recently diagnosed DM, which may be attributed to a paraneoplastic effect. However, the presence of diabetes also remains a modest risk factor for the development of PDAC long-term. Selective screening of patients with new-onset DM for PDAC needs to be considered.

The impact of perioperative blood glucose levels on pancreatic cancer prognosis and surgical outcomes: an evidence-based review

Although diabetes mellitus (DM) and pancreatic cancer (PC) are intricately linked, a comprehensive review addressing the impact of DM on PC prognosis and surgical outcomes is lacking. PubMed search was performed (1980-2012) using keywords "pancreatic cancer", "diabetes mellitus", "glucose intolerance", "pancreatic resection", "prognosis", and "post-operative outcomes". The search results were analyzed to determine the strength of association between DM and PC and to assess the impact of DM on PC prognosis and postoperative outcomes. Thirty-one studies involving 38,777 patients were identified. Patients with non-insulin-dependent DM have 1.5-2 fold increased relative risk of developing PC. Non-insulin-dependent DM is identified in 25.7% of patients with PC compared to 10.4% age-matched controls (95% confidence interval, 1.5-4.7; P < 0.0001). Patients with PC are more likely to have a diagnosis of new-onset DM than age-matched controls (14.7% vs 2.7%; P < 0.0001). Patients with PC with DM have a significantly lower overall survival than those without DM (14.4 vs 21.7 months; P < 0.001). The presence of DM significantly increases overall postoperative complication rates (45.6% vs 35.6%; P < 0.008). Patients with new-onset non-insulin-dependent DM are at a higher risk of developing PC and have a worse long-term survival and a higher rate of postoperative complications.

New insights into pancreatic cancer-induced paraneoplastic diabetes

Up to 85% of patients with pancreatic cancer have diabetes or hyperglycaemia, which frequently manifests as early as 2-3 years before a diagnosis of pancreatic cancer. Conversely, patients with new-onset diabetes have a 5-8-fold increased risk of being diagnosed with pancreatic cancer within 1-3 years of developing diabetes. Emerging evidence now indicates that pancreatic cancer causes diabetes. As in type 2 diabetes, β-cell dysfunction and peripheral insulin resistance are seen in pancreatic cancer-induced diabetes. However, unlike in patients with type 2 diabetes, glucose control worsens in patients with pancreatic cancer in the face of ongoing, often profound, weight loss. Diabetes and weight loss, which precede cachexia onset by several months, are paraneoplastic phenomena induced by pancreatic cancer. Although the pathogenesis of these pancreatic cancer-induced metabolic alterations is only beginning to be understood, these are likely mechanisms to promote the survival and growth of pancreatic cancer in a hostile and highly desmoplastic microenvironment. Interestingly, these metabolic changes could enable early diagnosis of pancreatic cancer, if they can be distinguished from the ones that occur in patients with type 2 diabetes. One such possible biomarker is adrenomedullin, which is a potential mediator of β-cell dysfunction in pancreatic cancer-induced diabetes.

Diabetes and pancreatic cancer

The relationship between diabetes and pancreatic cancer is complex. Diabetes or impaired glucose tolerance is present in more than 2/3rd of pancreatic cancer patients. Epidemiological studies have consistently shown a modest increase in the risk of pancreatic cancer in type 2 diabetes, with an inverse relationship to duration of disease. Additionally, recent studies suggest that anti-diabetic medications may modulate the risk of pancreatic cancer in type 2 diabetes. Subjects >50 years of age with new onset diabetes are at higher risk of having pancreatic cancer. However, to screen new-onset diabetes for pancreatic cancer, additional markers are needed that can distinguish pancreatic cancer-associated diabetes from type 2 diabetes.

Diabetes is a useful diagnostic clue to improve the prognosis of pancreatic cancer

BACKGROUND/OBJECTIVES

Diabetes mellitus (DM) is recognized as a risk factor for pancreatic cancer (PaC) and expected to be a clue for early diagnosis. However, it is still obscure whether a diagnostic strategy using DM as a clue can improve the prognosis or not.

METHODS

We retrospectively reviewed 540 patients with PaC, and investigated the prognosis with regard to the reasons for diagnosis. We compared patients diagnosed by imaging studies performed when DM was newly diagnosed or deteriorated, and patients diagnosed by symptoms.

RESULTS

The prevalence of DM in PaC patients was 45% (256/540) and did not differ between disease stages. More than half of DM in PaC patients (150/256) were new-onset (<2 years in duration). One hundred sixty one patients (30%) were asymptomatic at PaC diagnosis. There were 38 patients diagnosed in association with DM (by new-onset DM, 16; by aggravation of long-standing DM, 22). Asymptomatic patients had smaller primary tumor and were diagnosed at an earlier stage. The prognosis of PaC patients complicated with DM did not differ from that of patients without DM; however, patients had better prognosis if they were diagnosed in association with DM alone (median survival time, 20.2 months), compared with patients diagnosed by symptoms (10.2 months, P < 0.01).

CONCLUSIONS

Our analysis revealed that patients diagnosed in association with DM had better survival than symptomatic patients. Given the high prevalence of DM in PaC patients, DM can be a useful diagnostic clue for screening and lead to improvement of prognosis in PaC patients.

Diabetes and cancer: placing the association in perspective

PURPOSE OF REVIEW

The association of diabetes and cancer has received increased attention as data have emerged to indicate that the type of diabetes treatment may influence the risk of cancer, and that the risk of cancer among diabetic individuals can be reduced by intervention. The association of diabetes and pancreatic cancer is particularly strong, but often misunderstood. Long-standing type 1 diabetes and type 2 diabetes increase the risk for this malignancy, but the cancer can also induce pancreatogenic, or type 3c, diabetes as well.

RECENT FINDINGS

This review covers the recent findings which help to clarify these relationships, and offers guidance for prevention, early detection, and treatment. Obesity and, separately, diabetes increase the risk of several common malignancies by about two-fold. This risk is reduced by successful treatments. Type 3c diabetes is more common than previously realized, and strategies to differentiate type 3c diabetes from type 2 diabetes, to identify those candidates who will benefit from screening studies, are discussed.

SUMMARY

The death rate because of pancreatic and other cancers can be reduced by an aggressive approach to reversing obesity and hyperinsulinemia, achieving good glycemic control in diabetic patients, and identifying at an early timepoint those patients with pancreatogenic diabetes.

Risk factors and early signs of pancreatic cancer in diabetes: screening strategy based on diabetes onset age

BACKGROUND

Diabetes mellitus (DM) has long been recognized as a risk factor for pancreatic cancer (PaC) and recently has attracted attention as a manifestation of PaC. Diabetes is expected to be a clue for the early detection of PaC; however, no effective screening strategy has been established.

METHODS

Forty diabetic patients with PaC were identified and compared with 120 diabetic patients without any malignancies. We analyzed risk factors for and early signs of PaC, focusing on the DM-onset age.

RESULTS

As there were peaks at 40-45 years and 60-65 years in the distribution of DM-onset age, we analyzed the clinical characteristics of and risk factors for PaC according to DM-onset age: i.e., early-onset (< 55 years) and late-onset (≥ 55 years). PaC was diagnosed within 2 years of DM onset (new-onset) in 0% of the patients with early-onset DM, and in 33% of those with late-onset DM. The mean duration of DM in patients with early-onset DM with PaC was longer than that in the late-onset patients (26 vs. 9 years; P < 0.01). A family history of DM (odds ratio [OR] 3.60) and use of insulin (OR 3.52) were significant risk factors in patients with early-onset DM, while the onset age of DM (OR 1.12) and multiple diabetic patients in the family (OR 6.13) were risk factors in those with late-onset DM. Body weight loss and exacerbation of DM were seen 12 months prior to PaC diagnosis in both groups.

CONCLUSIONS

Our study revealed specific risk factors for and similar early signs of PaC in early-onset and late-onset DM. Thus, we could develop a screening strategy, combining these risk factors specific for DM-onset age with early signs of disease.

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

BACKGROUND & AIMS

New-onset diabetes in patients with pancreatic cancer is likely to be a paraneoplastic phenomenon caused by tumor-secreted products. We aimed to identify the diabetogenic secretory product(s) of pancreatic cancer.

METHODS

Using microarray analysis, we identified adrenomedullin as a potential mediator of diabetes in patients with pancreatic cancer. Adrenomedullin was up-regulated in pancreatic cancer cell lines, in which supernatants reduced insulin signaling in beta cell lines. We performed quantitative reverse-transcriptase polymerase chain reaction and immunohistochemistry on human pancreatic cancer and healthy pancreatic tissues (controls) to determine expression of adrenomedullin messenger RNA and protein, respectively. We studied the effects of adrenomedullin on insulin secretion by beta cell lines and whole islets from mice and on glucose tolerance in pancreatic xenografts in mice. We measured plasma levels of adrenomedullin in patients with pancreatic cancer, patients with type 2 diabetes mellitus, and individuals with normal fasting glucose levels (controls).

RESULTS

Levels of adrenomedullin messenger RNA and protein were increased in human pancreatic cancer samples compared with controls. Adrenomedullin and conditioned media from pancreatic cell lines inhibited glucose-stimulated insulin secretion from beta cell lines and islets isolated from mice; the effects of conditioned media from pancreatic cancer cells were reduced by small hairpin RNA-mediated knockdown of adrenomedullin. Conversely, overexpression of adrenomedullin in mice with pancreatic cancer led to glucose intolerance. Mean plasma levels of adrenomedullin (femtomoles per liter) were higher in patients with pancreatic cancer compared with patients with diabetes or controls. Levels of adrenomedullin were higher in patients with pancreatic cancer who developed diabetes compared those who did not.

CONCLUSIONS

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