The relationship between pancreatic cancer and type 2 diabetes: cause and consequence

Pancreatic Cancer Risk in Prediabetes: A Systematic Meta-analysis Approach

OBJECTIVES

Pancreatic cancer and prediabetes pose significant public health challenges. Given the lack of strong evidence we performed a meta-analysis to assess the risk of pancreatic cancer in prediabetes.

MATERIALS AND METHODS

We performed a thorough search of the major databases over the last 10 years to identify relevant articles. The pooled odds ratio (OR) and hazard ratio (HR) were combined to calculate the effect size (ES).

RESULTS

We analyzed 5 studies including 5,425,111 prediabetic individuals and 16,096,467 normoglycemic population across 5 countries with a median follow-up of 8.5 years. We identified a noteworthy association between prediabetes and pancreatic cancer, reporting an unadjusted ES of 1.36 (95% confidence interval [CI] 1.05-1.77, P = 0.02) and an adjusted ES of 1.40 (1.23-1.59, P < 0.01). Subgroup analyses by age revealed variations in risk, with studies involving participants aged 60 and above exhibiting a higher ES (ES 1.83, 95% CI 1.28-2.62, P < 0.01). Geographical differences were also observed, with Japanese studies reporting a higher risk (ES 1.89, 95% CI 1.15-3.10, P < 0.01) compared with those from the United States (ES 1.32, 95% CI 1.13-1.53, P < 0.01).

CONCLUSIONS

We identified 40% higher risk of pancreatic cancer in patients with prediabetes than those with normal blood glucose necessitating urgent attention for further research and policy change.

Associations between Diabetes Mellitus and Selected Cancers

Cancer is one of the major causes of mortality and is the second leading cause of death. Diabetes mellitus is a serious and growing problem worldwide, and its prevalence continues to grow; it is the 12th leading cause of death. An association between diabetes mellitus and cancer has been suggested for more than 100 years. Diabetes is a common disease diagnosed among patients with cancer, and evidence indicates that approximately 8-18% of patients with cancer have diabetes, with investigations suggesting an association between diabetes and some particular cancers, increasing the risk for developing cancers such as pancreatic, liver, colon, breast, stomach, and a few others. Breast and colorectal cancers have increased from 20% to 30% and there is a 97% increased risk of intrahepatic cholangiocarcinoma or endometrial cancer. On the other hand, a number of cancers and cancer therapies increase the risk of diabetes mellitus. Complications due to diabetes in patients with cancer may influence the choice of cancer therapy. Unfortunately, the mechanisms of the associations between diabetes mellitus and cancer are still unknown. The aim of this review is to summarize the association of diabetes mellitus with selected cancers and update the evidence on the underlying mechanisms of this association.

Identification of biomarkers and potential therapeutic targets for pancreatic cancer by proteomic analysis in two prospective cohorts

Pancreatic cancer (PC) is the deadliest malignancy due to late diagnosis. Aberrant alterations in the blood proteome might serve as biomarkers to facilitate early detection of PC. We designed a nested case-control study of incident PC based on a prospective cohort of 38,295 elderly Chinese participants with ∼5.7 years' follow-up. Forty matched case-control pairs passed the quality controls for the proximity extension assay of 1,463 serum proteins. With a lenient threshold of p < 0.005, we discovered regenerating family member 1A (REG1A), REG1B, tumor necrosis factor (TNF), and phospholipase A2 group IB (PLA2G1B) in association with incident PC, among which the two REG1 proteins were replicated using the UK Biobank Pharma Proteomics Project, with effect sizes increasing steadily as diagnosis time approaches the baseline. Mendelian randomization analysis further supported the potential causal effects of REG1 proteins on PC. Taken together, circulating REG1A and REG1B are promising biomarkers and potential therapeutic targets for the early detection and prevention of PC.

Novel Insights into Postoperative Surveillance in Resected Pancreatic Cystic Neoplasms-A Review

Pancreatic cystic lesions (PCL) are frequently encountered in clinical practice and some are referred to surgery due to their neoplastic risk or malignant transformation. The management of PCL involves complex decision-making, with postoperative surveillance being a key component for long-term outcomes, due to the potential for recurrence and postoperative morbidity. Unfortunately, the follow-up of resected patients is far from being optimal and there is a lack of consensus on recommendations with regard to timing and methods of surveillance. Here, we summarize the current knowledge on the postoperative surveillance of neoplastic pancreatic cysts, focusing on the mechanisms and risk factors for recurrence, the recurrence rates according to the initial indication for surgery, the final result of the surgical specimen and neoplastic risk in the remaining pancreas, as well as the postsurgical morbidity comprising pancreatic exocrine insufficiency, metabolic dysfunction and diabetes after resection, according to the type of surgery performed. We analyze postsurgical recurrence rates and morbidity profiles, as influenced by different surgical techniques, to better delineate at-risk patients, and highlight the need for tailored surveillance strategies adapted to preoperative and operative factors with an impact on outcomes.

A study on the relationship between malignancy and diabetes

BACKGROUND & AIMS

Today, malignancy and diabetes mellitus are important health problems with an increasing prevalence that have high morbidity and mortality. The purpose of this study was to examine the presence of overt diabetes mellitus (DM) in individuals with malignancy diagnosis, evaluate the effect of pre-diagnosis glucose control on the patients, DM duration and treatment options for malignancy development and type, and investigate the risk of DM development on non-diabetic patients with malignancy after cancer treatment.

METHODS

A total of 469 patients between the ages of 26 and 70 with different malignancies were divided into 3 groups. Group I: Patients with overt DM that were diagnosed before the malignancy diagnosis or diagnosed during the malignancy diagnosis (n = 97); Group II: Patients that developed DM during the malignancy (anticancer) treatment (n = 17), Group III: Non-diabetic patients with malignancy diagnosis (n = 355).

RESULTS

Group I participants were found to have the highest mean BMI value (33.2 ± 6.7 kg/m2) and lowest weekly physical activity duration (p < 0.05). While 28.8 % of the patients with overt DM before diagnosis were found not to be followed up for DM, 18.8 % were not using antidiabetic medication. A total of 29.4% of the patients who developed DM during the malignancy treatment were found to have pancreas surgery and 17.5 % had corticosteroid treatment.

CONCLUSIONS

Appropriate screening programs should be developed for diabetic patients, taking into account the common risk factors of cancer and DM. Also, oncological treatments in patients with malignancy may lead to the development of DM. Therefore, the effects of decided anticancer treatment on glucose metabolism should not be overlooked and glucose metabolism in the patient must be monitored regularly.

Predicting cell-type specific disease genes of diabetes with the biological network

Type 2 diabetes (T2D) is a chronic condition that can lead to significant harm, such as heart disease, kidney disease, nerve damage, and blindness. Although T2D-related genes have been identified through Genome-wide association studies (GWAS) and various computational methods, the biological mechanism of T2D at the cell type level remains unclear. Exploring cell type-specific genes related to T2D is essential to understand the cellular mechanisms underlying the disease. To address this issue, we introduce DiGCellNet (predicting Disease Genes with Cell type specificity based on biological Networks), a model that integrates graph convolutional network (GCN) and multi-task learning (MTL) to predict T2D-associated cell type-specific genes based on the biological network. Our work represents the first attempt to predict cell type-specific disease genes using GCN and MTL. We evaluate our approach by predicting genes specific to four cell types and demonstrate that the proposed DiGCellNet outperforms other models that combine node embeddings with traditional machine learning algorithms. Moreover, DiGCellNet successfully identifies CALM1 as a gene specific to beta cell type in T2D cases, and this association is confirmed using an independent dataset. The code is available at https://github.com/23AIBox/23AIBox-DiGCellNet.

Protein expression and localization of ABC transporters in pancreatic adenocarcinoma: Prognostic role of ABCC8

BACKGROUND

ATP-binding cassette (ABC) transporters translocate various substances across cellular membranes. Their deregulation may cause cancer drug resistance or perturbations in the supply of building blocks for cancer cells and modify patients' prognosis. This study investigated protein expression and cellular localization of the previously suggested putative prognostic biomarkers - ABCB2/TAP1, ABCC7/CFTR, ABCC8/SUR1, and ABCD4 in patients with pancreatic ductal adenocarcinoma (PDAC).

METHODS

Protein expression and localization were assessed by immunohistochemistry in formalin-fixed paraffin-embedded primary tumor tissue blocks of 61 PDAC patients and associated with clinical data and the survival of patients.

RESULTS

No CFTR protein expression was observed in PDAC, while TAP1 and ABCC8 were expressed predominantly in the cytoplasm of tumor cells. Most samples (81 %) had detectable both membranous and cytoplasmic ABCD4 staining and 42 % had ABCD4 expressed in the apical orientation. Negative membranous ABCD4 staining was significantly more frequent in advanced stage III or IV tumors (p = 0.022). Small or medium counts of individual ABCC8-positive cells in the stroma surrounding tumor tubules were also more often found in stage III or IV (p = 0.044). Patients with moderate or strong ABCC8 cytoplasmic staining intensity in tumor cells had a 3.5-fold higher risk of disease progression than those with weak staining (p = 0.002).

CONCLUSIONS

The study shows for the first time that the cytoplasmic ABCC8 protein expression has prognostic value in PDAC.

Association between pancreatic cancer and diabetes: insights from a retrospective cohort study

BACKGROUND

Studies investigating the prevalence of pancreatic cancer have revealed a heightened risk of 1.5 to 2.0 times among individuals with long-standing type 2 diabetes mellitus.

AIMS

We aimed to estimate the prevalence of diabetes among patients with pancreatic cancer, and identify the factors associated with type 2 diabetes mellitus in this population.

METHODS

This retrospective observational and analytical study was carried out in the Department of Gastroenterology of the Mohammed VI University Hospital over a period of 5 years, between 2018 and 2022, including all patients with confirmed cases of pancreatic adenocarcinoma.

RESULTS

Out of the 197 patients, 38.1% had a history of diabetes, among them, 42.7% had new-onset diabetes, while the remaining 57.3% had long-standing diabetes. Diabetic patients were significantly older than nondiabetic patients (mean age of 67.2 vs. 63, P = 0.009). Diabetes was more prevalent among obese patients (66.7%, P = 0.01), and less frequent among individuals with chronic alcohol consumption (20% vs. 80%, P = 0.04), and tobacco smokers (24.4% vs75.6%, P = 0.03). Among patients with an ECOG score ≥ 3, DM, 54.5% were DM-patients (P = 0.033). The same significant association was found for the Nutritional Risk Index, Patients who had moderate or severe malnutrition were more likely to be diabetic 74.7% (P = 0.004). Diabetic patients were less likely to undergo surgery due to comorbidities and general health deterioration. However, no significant differences were observed in sex, tumor stage or location.

CONCLUSION

Our study has shown an increased prevalence of diabetes in pancreatic cancer and highlights the importance of considering this cancer in cases of recent onset or uncontrolled diabetes, especially in elderly individuals.

Nutraceuticals as Supportive Therapeutic Agents in Diabetes and Pancreatic Ductal Adenocarcinoma: A Systematic Review

The correlation between pancreatic ductal adenocarcinoma (PDAC) and diabetes-related mechanisms support the hypothesis that early therapeutic strategies targeting diabetes can contribute to PDAC risk reduction and treatment improvement. A systematic review was conducted, using PubMed, Embase and Cochrane Library databases, to evaluate the current evidence from clinical studies qualitatively examining the efficacy of four natural products: Curcumin-Curcuma longa L.; Thymoquinone-Nigella sativa L.; Genistein-Glycine max L.; Ginkgo biloba L.; and a low-carbohydrate ketogenic diet in type 2 diabetes (T2D) and PDAC treatment. A total of 28 clinical studies were included, showing strong evidence of inter-study heterogeneity. Used as a monotherapy or in combination with chemo-radiotherapy, the studied substances did not significantly improve the treatment response of PDAC patients. However, pronounced therapeutic efficacy was confirmed in T2D. The natural products and low-carbohydrate ketogenic diet, combined with the standard drugs, have the potential to improve T2D treatment and thus potentially reduce the risk of cancer development and improve multiple biological parameters in PDAC patients.

Causal associations between site-specific cancer and diabetes risk: A two-sample Mendelian randomization study

BACKGROUND

Both cancer and diabetes are complex chronic diseases that have high economic costs for society. The co-occurrence of these two diseases in people is already well known. The causal effects of diabetes on the development of several malignancies have been established, but the reverse causation of these two diseases (e.g., what type of cancer can cause T2D) has been less investigated.

METHODS

Multiple Mendelian randomization (MR) methods, such as the inverse-variance weighted (IVW) method, weighted median method, MR-Egger, and MR pleiotropy residual sum and outlier test, were performed to evaluate the causal association of overall and eight site-specific cancers with diabetes risk using genome-wide association study summary data from different consortia, such as Finngen and UK biobank.

RESULTS

A suggestive level of evidence was observed for the causal association between lymphoid leukaemia and diabetes by using the IVW method in MR analyses (P = 0.033), indicating that lymphoid leukaemia increased diabetes risk with an odds ratio of 1.008 (95% confidence interval, 1.001-1.014). Sensitivity analyses using MR-Egger and weighted median methods showed consistent direction of the association compared with the IVW method. Overall and seven other site-specific cancers under investigation (i.e., multiple myeloma, non-Hodgkin lymphoma, and cancer of bladder, brain, stomach, lung, and pancreas) were not causally associated with diabetes risk.

CONCLUSIONS

The causal relationship between lymphoid leukaemia and diabetes risk points to the necessity of diabetes prevention amongst leukaemia survivors as a strategy for ameliorating the associated disease burden.

Influence of antidiabetic drugs on glucose metabolism and immune response in patients with metastatic pancreatic ductal adenocarcinoma receiving gemcitabine plus nab-paclitaxel as first-line treatment

BACKGROUND

Association between pancreatic ductal adenocarcinoma (PDAC) and type 2 diabetes mellitus (DM2) has long been evaluated. Indeed, DM2 can be both an epiphenomenon of PDAC and a risk factor. The present study aimed to investigate the correlation between overall survival (OS) and antidiabetic drugs in patients with metastatic pancreatic ductal adenocarcinoma and DM2.

METHOD

Data from 232 patients were collected retrospectively from 2014 to 2021. 174 from AOU Cagliari Medical Oncology and 58 from AOU Ancona Medical Oncology. All patients received gemcitabine plus nab-paclitaxel first-line chemotherapy. We aimed to evaluate the correlation between DM2, anti-diabetic medications and overall survival. Survival distribution was assessed by Kaplan-Meier curves.

RESULTS

Median age was 68±9, 127 (55%) were male. 138/232 (59%) patients were not affected by DM2, 94/232 (41%) were affected by DM2. 57 were insulin-treated and 37 were metformin-treated. DM2 treated patients showed an higher median overall survival (26 vs 12 months, p = 0,0002). Among DM2 patients insulin-treated and metformin-treated showed an mOS of 21 months and 33 months, respectively.

CONCLUSIONS

Results showed a correlation between treated DM2 and higher mOS in patients with mPDAC. Limitations due to retrospective data collection must be considered. Further studies in this setting are needed.

Implications of cancer stem cells in diabetes and pancreatic cancer

This review provides a detailed study of pancreatic cancer (PC) and the implication of different types of cancers concerning diabetes. The combination of anti-diabetic drugs with other anti-cancer drugs and phytochemicals can help prevent and treat this disease. PC cancer stem cells (CSCs) and how they migrate and develop into malignant tumors are discussed. A detailed explanation of the different mechanisms of diabetes development, which can enhance the pancreatic CSCs' proliferation by increasing the IGF factor levels, epigenetic modifications, DNA damage, and the influence of lifestyle factors like obesity, and inflammation, has been discussed. It also explains how cancer due to diabetes is associated with high mortality rates. One of the well-known diabetic drugs, metformin, can be combined with other anti-cancer drugs and prevent the development of PC and has been taken as one of the prime focus in this review. Overall, this paper provides insight into the relationship between diabetes and PC and the methods that can be employed to diagnose this disease at an earlier stage successfully.

The Role of Type 2 Diabetes in Pancreatic Cancer

The incidence of type 2 diabetes mellitus (T2DM) and its potential complications, such as cancers, are increasing worldwide at an astounding rate. There are many factors such as obesity, diabetes, alcohol consumption, and the adoption of sedentary lifestyles that are driving pancreatic cancer (PC) to become one of the leading causes of cancer mortality in the United States. PC is notorious for its generic symptoms and late-stage presentation with rapid metastasis. The connection between T2DM and the risk of PC development is multifaceted and complex. Some of the proposed theories reveal that chronic inflammation, insulin resistance, hyperinsulinemia, hyperglycemia, and abnormalities in the insulin and insulin-like growth factor axis (IGF) contribute to the disease association between these two conditions. This literature review aims to highlight relevant studies and explore the molecular mechanisms involved in the etiology of diabetes and its impact on PC development, as well as the role of anti-diabetic agents on PC. Despite extensive studies, the exact interaction between T2DM and PC remains obscure and will need further investigation. According to current knowledge, there is a substantial link between diabetes, obesity, and dietary patterns in the development and progression of PC. Consequently, focusing our efforts on preventive measures by reducing modifiable risk factors remains the most effective strategy to reduce the risk of PC at this time. Antidiabetic drugs can have various effects on the occurrence and prognosis of PC with metformin offering a clear benefit of inhibiting PC and insulin increasing the risk of PC. The development of future novel therapies will require a deeper knowledge of the triggering mechanisms and interplay between these two disease states.

Pancreatic Cancer and Microenvironments: Implications of Anesthesia

Simple Summary

Pancreatic cancer is a lethal malignant neoplasm with less than 10% 5-year relative survival after the initial diagnosis. Several factors may be related to the poor prognosis of pancreatic cancer, including the rapid tumor progression, increased metastatic propensity, insignificant symptoms, shortage of early diagnostic biomarkers, and its tendency toward resistance to both chemotherapy and radiotherapy. Pancreatic neoplastic cells interact intimately with a complicated microenvironment that can foster drug resistance, metastasis, or relapse in pancreatic cancer. In addition, evidence shows that perioperative factors, including surgical manipulation, anesthetics, or analgesics, might alter the tumor microenvironment and cancer progression. This review outlines the up-to-date knowledge of anesthesia implications in the pancreatic microenvironment and provides future anesthetic strategies for improving pancreatic cancer survival.

Abstract

Pancreatic malignancy is a lethal neoplasm, as well as one of the leading causes of cancer-associated mortality, having a 5-year overall survival rate of less than 10%. The average life expectancy of patients with advanced pancreatic cancer does not exceed six months. Although surgical excision is a favorable modality for long-term survival of pancreatic neoplasm, metastasis is initially identified in nearly 80% of the patients by the time of diagnosis, making the development of therapeutic policy for pancreatic cancer extremely daunting. Emerging evidence shows that pancreatic neoplastic cells interact intimately with a complicated microenvironment that can foster drug resistance, metastasis, or relapse in pancreatic cancer. As a result, the necessity of gaining further insight should be focused on the pancreatic microenvironment contributing to cancer progression. Numerous evidence reveals that perioperative factors, including surgical manipulation and anesthetics (e.g., propofol, volatile anesthetics, local anesthetics, epidural anesthesia/analgesia, midazolam), analgesics (e.g., opioids, non-steroidal anti-inflammatory drugs, tramadol), and anesthetic adjuvants (such as ketamine and dexmedetomidine), might alter the tumor microenvironment and cancer progression by affecting perioperative inflammatory or immune responses during cancer surgery. Therefore, the anesthesiologist plays an important role in perioperative management and may affect surgical outcomes. However, the literature on the impact of anesthesia on the pancreatic cancer microenvironment and progression is limited. This review summarizes the current knowledge of the implications of anesthesia in the pancreatic microenvironment and provides future anesthetic strategies for improving pancreatic cancer survival rates.

The Impact of Pancreatic Exocrine Diseases on the β-Cell and Glucose Metabolism-A Review with Currently Available Evidence

Pancreatic exocrine and endocrine dysfunctions often come together in the course of pancreatic diseases as interdependent manifestations of the same organ. However, the mechanisms underlying the bidirectional connection of the exocrine and endocrine pancreas are not fully understood. In this review, we aimed to synthetize the current knowledge regarding the effects of several exocrine pancreatic pathologies on the homeostasis of β-cells, with a special interest in the predisposition toward diabetes mellitus (DM). We focused on the following pancreatic exocrine diseases: chronic pancreatitis, acute pancreatitis, cystic fibrosis, pancreatic cancer, pancreatic resections, and autoimmune pancreatitis. We discuss the pathophysiologic mechanisms behind the impact on β-cell function and evolution into DM, as well as the associated risk factors in progression to DM, and we describe the most relevant and statistically significant findings in the literature. An early and correct diagnosis of DM in the setting of pancreatic exocrine disorders is of paramount importance for anticipating the disease's course and its therapeutical needs.

Identification of the Shared Gene Signatures and Biological Mechanism in Type 2 Diabetes and Pancreatic Cancer

Background

The relationship between pancreatic cancer (PC) and type 2 diabetes mellitus (T2DM) has long been widely recognized, but the interaction mechanisms are still unknown. This study was aimed to investigate the shared gene signatures and molecular processes between PC and T2DM.

Methods

The Gene Expression Omnibus (GEO) database was used to retrieve the RNA sequence and patient information of PC and T2DM. Weighted gene co-expression network analysis (WGCNA) was performed to discover a co-expression network associated with PC and T2DM. Enrichment analysis of shared genes present in PC and T2DM was performed by ClueGO software. These results were validated in the other four cohorts based on differential gene analysis. The predictive significance of S100A6 in PC was evaluated using univariate and multivariate Cox analyses, as well as Kaplan-Meier plots. The biological process of S100A6 enrichment in PC was detected using Gene Set Enrichment Analysis (GSEA). The involvement of S100A6 in the tumor immune microenvironment (TIME) was assessed by CIBERSORT. In vitro assays were used to further confirm the function of S100A6 in PC.

Results

WGCNA recognized three major modules for T2DM and two major modules for PC. There were 44 shared genes identified for PC and T2DM, and Gene Ontology (GO) analysis showed that regulation of endodermal cell fate specification was primarily enriched. In addition, a key shared gene S100A6 was derived in the validation tests. S100A6 was shown to be highly expressed in PC compared to non-tumor tissues. PC patients with high S100A6 expression had worse overall survival (OS) than those with low expression. GSEA revealed that S100A6 is involved in cancer-related pathways and glycometabolism-related pathways. There is a strong relationship between S100A6 and TIME. In vitro functional assays showed that S100A6 helped to induce the PC cells' proliferation and migration. We also proposed a diagram of common mechanisms of PC and T2DM.

Conclusions

This study firstly revealed that the regulation of endodermal cell fate specification may be common pathogenesis of PC and T2DM and identified S100A6 as a possible biomarker and therapeutic target for PC and T2DM patients.

[Diabetes mellitus and cancer: a system of insulin-like growth factors]

Diabetes mellitus and malignant tumors are among the most common and complex diseases. Epidemiological studies have shown a strong relationship between these pathologies. The causality of this relationship has not yet been unambiguously established, but a number of probable biological mechanisms have been proposed to explain it through the effects of hyperglycemia, hyperinsulinemia on the process of oncogenesis. An important role in this is played by the axis of insulin-like growth factors, their receptors and binding proteins (IGF / IGFR / IGFBP). The review provides data on the structural elements of the insulin / IGF / IGFR / IGFBP signaling axis and their internal relationships in diabetes mellitus and in the development of malignant tumors. Significant changes in the axis that occur during the formation of the diabetic environment prepare the background, which, under certain conditions, can lead to the stimulation or inhibition of tumor development. The considered signaling system, playing a significant role in the physiology of normal cells, often functions as a decisive factor in the survival of tumor cells, providing fine context-dependent regulation of many cellular processes associated with oncogenesis. However, despite many years of in-depth studies of the pathogenesis of diabetes mellitus and malignant tumors, the molecular mechanisms of the relationship between these pathologies are still largely unclear, and the internal heterogeneity of pathologies complicates research and interpretation of the results, leaving many questions.

Programmed Death-Ligand 1 (PD-L1) Expression Is Induced by Insulin in Pancreatic Ductal Adenocarcinoma Cells Pointing to Its Role in Immune Checkpoint Control

Type-2 diabetes (T2DM) is a risk factor for the development of pancreatic ductal adenocarcinoma (PDAC) and is characterized by insulin resistance and hyperinsulinemia. Besides the well-known growth-promoting activity of insulin or the other members of the Insulin/Insulin-like Growth factor (IGF) axis, we here describe an inducing effect of insulin on PD-L1 expression in PDAC cells. Treatment of the PDAC cell lines BxPc3, A818-6, and T3M4 with insulin increased PD-L1 expression in a time- and dose dependent fashion, as shown by Western blot and qPCR analysis. siRNA mediated knock-down showed that the effects of insulin on PD-L1 depend on the insulin and IGF receptors (InsR and IGFR, respectively). In addition, a crosstalk of insulin-induced ERK activation and Epidermal Growth Factor (EGF) triggered PD-L1 expression. This involves different mechanisms in the three cell lines including upregulation of InsR-A expression in A818-6 and modulation of the adaptor protein Gab1 in BxPc3 cells. As a consequence of the insulin-induced PD-L1 expression, PDAC cells suppress the proliferation of activated human CD8+ T-cells in coculture experiments. The suppression of CD8+ cell proliferation by insulin-pretreated PDAC cells was reversed by PD-1 blockade with Pembrolizumab or by PD-L1 siRNA. Furthermore, the clinical relevance of these observations was supported by detecting a coexpression of cytoplasmic InsR (characteristic for its activation) and PD-L1 in tumor tissues from PDAC patients. Our findings provide a novel insight into the protumorigenic role of insulin in PDAC. Recognizing the impact of insulin on PD-L1 expression as part of the immune privilege, strategies to interfere with this mechanism could pave the way towards a more efficient immunotherapy of PDAC.

Association between fasting blood glucose levels at admission and overall survival of patients with pancreatic cancer

BACKGROUND

The associations between fasting blood glucose and staging and overall survival of patients with pancreatic cancer are still controversial. This study aimed to investigate the association between fasting blood glucose levels and overall survival (OS) of patients with pancreatic cancer and to evaluate the impact of differentiation and staging of pancreatic cancer.

METHODS

This was a retrospective study of patients with pathologically confirmed pancreatic cancer admitted to Shengjing Hospital of China Medical University between 01/2012 and 12/2016. The outcome was the OS. The factors associated with OS were examined using univariable and multivariable Cox and logistic regression analyses.

RESULTS

A total of 253 patients were included. Preoperative blood glucose levels were not significantly associated with the OS of patients with pancreatic cancer (HR = 1.04, 95%CI: 0.78-1.40, P = 0.781). Only CA199 > 1000 was independently associated with OS (HR = 1.86, 95%CI: 1.15-3.02, P = 0.012). The median survival in the normal glucose group was 20.5 months (95% confidence interval (CI): 14.2-26.9). The median survival in the high glucose group was 14.2 months (95% CI: 9.7-18.6). There was no statistically significant difference between the two groups (P = 0.573). Multivariable logistic regression analyses were performed to determine if blood glucose levels influenced the 1- and 2-year OS. No significant association was observed for 1-year (OR = 1.27, 95%CI: 0.71-2.29, P = 0.418) or 2-year (HR = 1.37, 95%CI: 0.76-2.46, P = 0.296) OS.

CONCLUSIONS

Fasting blood glucose levels are not associated with the OS of patients with pancreatic adenocarcinoma.

Diabetes and Pancreatic Cancer-A Dangerous Liaison Relying on Carbonyl Stress

Both type 2 (T2DM) and type 1 (T1DM) diabetes mellitus confer an increased risk of pancreatic cancer in humans. The magnitude and temporal trajectory of the risk conferred by the two forms of diabetes are similar, suggesting a common mechanism. Carbonyl stress is a hallmark of hyperglycemia and dyslipidemia, which accompanies T2DM, prediabetes, and obesity. Accumulating evidence demonstrates that diabetes promotes pancreatic ductal adenocarcinoma (PDAC) in experimental models of T2DM, a finding recently confirmed in a T1DM model. The carbonyl stress markers advanced glycation end-products (AGEs), the levels of which are increased in diabetes, were shown to markedly accelerate tumor development in a mouse model of Kras-driven PDAC. Consistently, inhibition of AGE formation by trapping their carbonyl precursors (i.e., reactive carbonyl species, RCS) prevented the PDAC-promoting effect of diabetes. Considering the growing attention on carbonyl stress in the onset and progression of several cancers, including breast, lung and colorectal cancer, this review discusses the mechanisms by which glucose and lipid imbalances induce a status of carbonyl stress, the oncogenic pathways activated by AGEs and their precursors RCS, and the potential use of carbonyl-scavenging agents and AGE inhibitors in PDAC prevention and treatment, particularly in high-risk diabetic individuals.

Diverse transitions in diabetes status during the clinical course of patients with resectable pancreatic cancer

OBJECTIVE

Pancreatic cancer and diabetes status have complex bilateral interactions; therefore, understanding their clinical features is essential for the clinical management of pancreatic cancer patients. We aimed to evaluate the diabetes status before diagnosis, after resection and until the time of recurrence in patients with resectable pancreatic cancer and to clarify the correlations among the clinical course of pancreatic cancer, operative procedure and diabetes status.

METHODS

Between 2011 and 2016, we retrospectively identified 189 pancreatic cancer patients who underwent pancreatoduodenectomy or distal pancreatectomy at our institution. The entire clinical course of each patient was retrieved from the medical records, and the diabetes status in the longest possible duration was assessed.

RESULTS

Among 115 pancreatic cancer patients who had normal glucose tolerance at the time of resection, 22 (19.1%) developed type 2 diabetes after resection. In a multivariate analysis, distal pancreatectomy was strongly associated with the development of postoperative diabetes. On the other hand, 74 pancreatic cancer patients had already been diagnosed with type 2 diabetes at the time of resection. During the follow-up period, 15 patients were noted to have diabetes resolution after resection; interestingly, the majority of these patients had newly diagnosed diabetes, which was defined as the diagnosis of diabetes within 3 months before resection. Moreover, newly diagnosed diabetes was an independent factor for diabetes resolution after resection.

CONCLUSIONS

In pancreatic cancer patients who underwent pancreatectomy, distal pancreatectomy was correlated with postoperative diabetes, and newly diagnosed diabetes had a high probability of resolution after resection.

Locally Advanced Pancreatic Ductal Adenocarcinoma: Challenges and Progress

Pancreatic ductal adenocarcinoma (PDAC) is one of the major causes of death in the Western world, and it is estimated to become the second leading cause of tumour-related mortality in the next 10 years. Among pancreatic cancers, ductal adenocarcinomas are by far the most common, characterised by a challenging diagnosis due to the lack of initial and pathognomonic clinical signs. In this scenario, non-metastatic locally advanced pancreatic cancer (LAPC) accounts for a large proportion of all new pancreatic ductal adenocarcinoma diagnoses. There is no consensus on a common definition of LAPC. Still, it usually includes tumours that are not resectable due to vascular involvement. As of today, treatment is limited, and the prognosis is very unfavourable. Curative-intent surgery remains the gold-standard even if often jeopardized by vascular involvement. Continuing progress in our understanding of LAPC genetics and immunology will permit the development of different treatments, targeted or combined, including radiation therapy, hadrontherapy, targeted immunotherapies or new chemotherapies. A multidisciplinary approach combining various fields of expertise is essential in aiming to limit disease progression as well as patient outcome. Using a narrative literature review approach, the manuscript explores the most up-to-date knowledge concerning locally advanced pancreatic ductal adenocarcinoma management.

Relationships are between metformin use and survival in pancreatic cancer patients concurrent with diabetes: A systematic review and meta-analysis

BACKGROUND

Increased risk and cancer-related mortality is observed in pancreatic cancer (PC) patients with diabetes mellitus (DM). Whether using metformin as glucose-lowering therapy can result in survival benefit in this group of patients is still unclear.

METHODS

A meta-analysis of 21 studies that including 38,772 patients was performed to investigate the association between metformin and overall survival in patients with PC and concurrent DM.

RESULTS

A significant survival benefit was observed in metformin treatment group compared with non-metformin group (hazard ratio [HR] = 0.83, 95% confidence interval [CI]: 0.74-0.91). These associations were observed in both subgroups of Asian countries (HR = 0.69, 95% CI: 0.60-0.79) and Western countries (HR = 0.86, 95% CI: 0.76-0.95), the former was more obvious. Survival benefit was gained for patients at early stage (HR = 0.75, 95% CI: 0.64-0.85) and mixed stage (HR = 0.81, 95% CI: 0.70-0.91), but not for patients at advanced stage (HR = 0.99, 95% CI: 0.74-1.24). Similarly, survival benefit was also observed in patients receiving surgery (HR = 0.82, 95% CI: 0.69-0.94) and comprehensive treatment (HR = 0.85, 95% CI: 0.77-0.93), but not in chemotherapy group (HR = 0.99, 95% CI: 0.67-1.30). No obvious benefit was suggested when pooled by time-varying COX model (HR = 0.94, 95% CI: 0.86-1.03).

CONCLUSIONS

These results suggest that metformin is associated with survival benefit in patients with PC and concurrent DM. Further randomized controlled trials and prospective studies with larger sample sizes are required to confirm our findings.

Natural Product Luteolin Rescues THAP-Induced Pancreatic β-Cell Dysfunction through HNF4α Pathway

Endoplasmic reticulum stress (ER stress) plays a main role in pancreatic [Formula: see text]-cell dysfunction and death because of intracellular Ca[Formula: see text] turbulence and inflammation activation. Although several drugs are targeting pancreatic [Formula: see text]-cell to improve [Formula: see text]-cell function, there still lacks agents to alleviate [Formula: see text]-cell ER stress conditions. Therefore we used thapsigargin (THAP) or high glucose (HG) to induce ER stress in [Formula: see text]-cell and aimed to screen natural molecules against ER stress-induced [Formula: see text]-cell dysfunction. Through screening the Traditional Chinese drug library ([Formula: see text] molecules), luteolin was finally discovered to improve [Formula: see text]-cell function. Cellular viability results indicated luteolin reduced the THAP or HG-induced [Formula: see text]-cell death and apoptosis through MTT and flow cytometry assay. Moreover, luteolin improved [Formula: see text]-cell insulin secretion ability under ER stress conditions. Also ER stress-induced intracellular Ca[Formula: see text] turbulence and inflammation activation were inhibited by luteolin treatment. Mechanically, luteolin inhibited HNF4[Formula: see text] signaling, which was induced by ER stress. Moreover, luteolin reduced the transcriptional level of HNF4[Formula: see text] downstream gene, such as Asnk4b and HNF1[Formula: see text]. Conversely HNF4[Formula: see text] knockdown abolished the effect of luteolin on [Formula: see text]-cell using siRNA. These results suggested the protective effect of luteolin on [Formula: see text]-cell was through HNF4[Formula: see text]/Asnk4b pathway. In conclusion, our study discovered that luteolin improved [Formula: see text]-cell function and disclosed the underlying mechanism of luteolin on [Formula: see text]-cell, suggesting luteolin is a promising agent against pancreatic dysfunction.

Insulin Reduces the Efficacy of Vemurafenib and Trametinib in Melanoma Cells

BACKGROUND

Despite the progress made in the clinical management of metastatic melanoma, a patient's response to treatment cannot be fully predicted, and intrinsic or acquired resistance that is developed in most melanoma patients warrants further research efforts. In addition to genetic factors, microenvironmental input should be considered to explain the diversity of response to treatment among melanoma patients. In this study, we evaluated the impact of insulin on patient-derived BRAFV600E melanoma cells, either untreated or treated with vemurafenib or trametinib, inhibitors of BRAFV600 and MEK1/2, respectively.

METHODS

Cells were cultured in serum-free conditions, either with or without insulin. The activity of the MAPK/ERK and PI3K/AKT pathways was assessed by Western blotting, cell viability, and percentages of Ki-67- and NGFR-positive cells by flow cytometry. Transcript levels were analyzed using qRT-PCR, and γ-H2AX levels by immunoblotting and confocal microscopy. A luminescence-based assay was used to measure glutathione content.

RESULTS

While insulin did not influence the MAPK/ERK pathway activity, it had a strong influence on melanoma cells, in which this pathway was suppressed by either vemurafenib or trametinib. In the presence of insulin, both drugs were much less efficient in 1) inhibiting proliferation and reducing the percentage of Ki-67-positive cells, and 2) inducing apoptosis and phosphorylation of histone H2AX in melanoma cells. Changes induced by vemurafenib and trametinib in glutathione homeostasis and DNA repair gene expression were also attenuated by insulin. Moreover, insulin impaired the combined effects of targeted drugs and doxorubicin in melanoma cells. In addition to insulin-induced PI3K/AKT activity, which was either transient or sustainable depending on the cell line, an insulin-triggered increase in the percentage of cells expressing NGFR, a marker of neural crest stem-like cells, may contribute to the reduced drug efficacy.

CONCLUSION

Our results demonstrate the role of insulin in reducing the efficacy of vemurafenib and trametinib. This needs clinical assessment.

Diabetes and cancer: Epidemiological and biological links

The incidence of diabetes and cancer has increased significantly in recent years. Furthermore, there are many common risk factors for both diabetes and cancer, such as obesity, sedentary lifestyle, smoking, and ageing. A large body of epidemiological evidence has indicated that diabetes is considered as an independent risk factor for increased rates of heterogeneous types of cancer occurrence and death. The incidence and mortality of various types of cancer, such as pancreas, liver, colorectal, breast, endometrial, and bladder cancers, have a modest growth in diabetics. However, diabetes may work as a protective factor for prostate cancer. Although the underlying biological mechanisms have not been totally understood, studies have validated that insulin/insulin-like growth factor (IGF) axis (including insulin resistance, hyperinsulinemia, and IGF), hyperglycemia, inflammatory cytokines, and sex hormones provide good circumstances for cancer cell proliferation and metastasis. Insulin/IGF axis activates several metabolic and mitogenic signaling pathways; hyperglycemia provides energy for cancer cell growth; inflammatory cytokines influence cancer cell apoptosis. Thus, these three factors affect all types of cancer, while sex hormones only play important roles in breast cancer, endometrial cancer, and prostate cancer. This minireview consolidates and discusses the epidemiological and biological links between diabetes and various types of cancer.