New-onset diabetes: a potential clue to the early diagnosis of pancreatic cancer

Prediagnostic body mass index and pancreatic cancer survival

PURPOSE

Although obesity is associated with increased incidence of pancreatic cancer, studies have not prospectively evaluated prediagnostic body mass index (BMI) and survival.

PATIENTS AND METHODS

We analyzed survival by prediagnostic BMI assessed in 1986 among 902 patients from two large prospective cohorts diagnosed from 1988 to 2010. We estimated hazard ratios (HRs) for death using Cox proportional hazards models, with adjustment for age, sex, race/ethnicity, smoking, diagnosis year, and stage. We evaluated the temporal association of BMI with survival by grouping reported BMI by 2-year lag-time intervals before diagnosis.

RESULTS

The multivariable-adjusted HR for death was 1.53 (95% CI, 1.11 to 2.09) comparing patients with BMI ≥ 35 kg/m(2) with those with BMI < 25 kg/m(2) (P trend = .001), which was similar after adjustment for stage. The association of BMI with survival was stronger with longer lag times between reported BMI and cancer diagnosis. Among patients with BMI collected 18 to 20 years before diagnosis, HR for death was 2.31 (95% CI, 1.48 to 3.61; P trend < .001), comparing obese with healthy-weight patients. No statistically significant differences were seen by cohort, smoking status, or stage, although the association was stronger among never-smokers (HR, 1.61; 95% CI, 1.01 to 2.57; P trend = .002) than ever-smokers (HR, 1.36; 95% CI, 0.86 to 2.15; P trend = .63), comparing BMI ≥ 35 kg/m(2) with BMI < 25 kg/m(2). Higher prediagnostic BMI was associated with more advanced stage at diagnosis, with 72.5% of obese patients presenting with metastatic disease versus 59.4% of healthy-weight patients (P = .02).

CONCLUSION

Higher prediagnostic BMI was associated with statistically significantly decreased survival among patients with pancreatic cancer from two large prospective cohorts.

Significance of expression of Yes-associated protein in pancreatic cancer

AIM: To detect the expression of Yes-associated protein (YAP), a component of the Hippo signaling pathway, in human pancreatic cancer, and to explore the correlation between the expression of YAP and clinicopathologic features of pancreatic cancer.

METHODS: Immunohistochemistry was used to investigate the protein expression of YAP in 45 pancreatic cancer specimens and 15 normal pancreatic tissue specimens. The mRNA expression of YAP was detected by RT-PCR.

RESULTS: YAP was mainly expressed in pancreatic ductal epithelial cells. The positive rate of YAP expression was significantly higher in pancreatic cancer than in normal pancreatic tissue (93.33% vs 26.67%, P < 0.05). The mRNA expression of YAP in pancreatic cancer was significantly higher than that in normal pancreatic tissue (0.3682 ± 0.0783 vs 0.0394 ± 0.0091, P < 0.05). The expression of YAP was associated with degree of differentiation of pancreatic cancer but had no correlation with age, lymph node metastasis, clinical stage, smoking, drinking, or diabetes mellitus.

CONCLUSION: The expression of YAP may play an important role in the development of pancreatic cancer, and YAP may be a new target for therapy of pancreatic cancer.

Pathohistological subtype predicts survival in patients with intraductal papillary mucinous neoplasm (IPMN) of the pancreas

OBJECTIVE

To investigate different subtypes of intraductal papillary mucinous neoplasms (IPMNs) of the pancreas and their prognostic value.

BACKGROUND

IPMNs of the pancreas are estimated to have a better prognosis than pancreatic ductal adenocarcinomas (PDACs). In addition to the different growth types (ie, main duct vs. branch duct types), the histological subtypes of IPMNs (ie, intestinal, pancreatobiliary, gastric, and oncocytic type) are prognostically relevant. These subtypes can be characterized by different mucin (MUC) expression patterns. In this study, we analyzed the IPMNs from 2 pancreatic cancer referral centers by correlating the MUC expression, histological subtype, and clinical outcome.

METHODS

We re-evaluated all resections due to a pancreatic tumor over a period of 15 years. Cases with IPMNs were identified, and the subtypes were distinguished using histopathological analysis, including the immunohistochemical analysis of MUC (ie, MUC1, MUC2, and MUC5AC) expression. Furthermore, we determined clinical characteristics and patient outcome.

RESULTS

A total of 103 IPMNs were identified. On the basis of the MUC profile, histopathological subtypes were classified into the following categories: intestinal type [n = 45 (44%)], pancreatobiliary type [n = 41 (40%)], gastric type [n = 13 (12%)], and oncocytic type [n = 4 (4%)]. The following types of resections were performed: pancreatic head resections [n = 77 (75%)], tail resections [n = 16 (15%)], total pancreatectomies [n = 5 (5%)], and segment resections [n = 5 (5%)]. The 5-year survival of patients with intestinal IPMNs was significantly better than pancreatobiliary IPMNs (86.6% vs. 35.6%; P < 0.001). The pancreatobiliary subtype was strongly associated with malignancy [odds ratio (OR): 6.76], recurrence (P < 0.001), and long-term survival comparable with that of PDAC patients.

CONCLUSIONS

Evaluation of IPMN subtypes supports postoperative patient prognosis prediction. Therefore, subtype differentiation could lead to improvements in clinical management. Potentially identifying subgroups with the need for adjuvant therapy may be possible.

Biomarkers in pancreatic cancer: diagnostic, prognostic, and predictive

Pancreatic cancer is the fourth leading cause of cancer-related death in the United States. There has been minimal progress with regard to cancer-specific outcomes in recent decades. Although effective therapies will undoubtedly change the natural history of the disease, effective biomarkers are a promising tool that will likely have a positive impact and will undoubtedly have an important role in the management of patients with pancreatic ductal adenocarcinoma (PDA) in the future. At present, serum CA-19-9 (carbohydrate antigen 19-9) is the only Food and Drug Administration-approved biomarker for PDA, and it has utility as a prognostic marker and as a marker of disease recurrence. There has been a recent explosion in the pancreatic cancer biomarker field with more than 2000 biomarker studies implicating thousands of informative genes as candidate biomarkers. In this review, we summarize the literature on CA-19-9 in PDA and highlight the most promising investigational biomarkers. Distinctions are made between diagnostic biomarkers (detection of disease), prognostic biomarkers (provide information on prognosis and recurrence pattern), and predictive biomarkers (predict treatment response).

Hyperglycemia, insulin resistance, impaired pancreatic β-cell function, and risk of pancreatic cancer

BACKGROUND

Obesity and diabetes mellitus are associated with an increased risk of pancreatic cancer. These associations may be secondary to consequences of peripheral insulin resistance, pancreatic β-cell dysfunction, or hyperglycemia itself. Hemoglobin A1c (HbA1c) is a measure of hyperglycemia, whereas plasma insulin and proinsulin are markers of peripheral insulin resistance, and the proinsulin to insulin ratio marks pancreatic β-cell dysfunction.

METHODS

This was a prospective, nested case-control study of 449 case patients and 982 control subjects with prediagnostic blood samples and no diabetes history from five prospective US cohorts followed through 2008. Two or three control subjects were matched to each case patient by year of birth, cohort, smoking, and fasting status. Pancreatic cancer risk was assessed by prediagnostic HbA1c, insulin, proinsulin, and proinsulin to insulin ratio with multivariable-adjusted logistic regression. All P values were two-sided.

RESULTS

The highest vs lowest quintiles of HbA1c, insulin, and proinsulin were associated with with an increased risk for pancreatic cancer (odds ratio [OR] = 1.79; 95% confidence interval [CI] = 1.17 to 2.72, P trend = .04 for HbA1c; OR = 1.57; 95% CI = 1.08 to 2.30; Ptrend = .002 for insulin; and OR = 2.22; 95% CI = 1.50 to 3.29; P trend < .001 for proinsulin). Proinsulin to insulin ratio was not associated with pancreatic cancer risk. Results were similar across studies (all P heterogeneity > .29). In cancers developing 10 or more years after blood collection, the associations with insulin and proinsulin became stronger (highest vs lowest quintile, OR = 2.77; 95% CI = 1.28 to 5.99 for insulin and OR = 3.60; 95% CI = 1.68 to 7.72 for proinsulin). In mutually adjusted models including HbA1c, insulin, and proinsulin, only proinsulin remained statistically significant ( highest vs lowest quintile, OR = 2.55; 95% CI = 1.54 to 4.21; Ptrend < .001).

CONCLUSIONS

Among participants from five large prospective cohorts, circulating markers of peripheral insulin resistance, rather than hyperglycemia or pancreatic β-cell dysfunction, were independently associated with pancreatic cancer risk.

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.

Risk factors for intraductal papillary mucinous neoplasm (IPMN) of the pancreas: a multicentre case-control study

OBJECTIVES

To investigate environmental, personal, and hereditary risk factors associated with the occurrence of intraductal papillary mucinous neoplasms of the pancreas (IPMNs).

METHODS

Multicentre case-control study. Risk factors were identified from a questionnaire collecting data on family and medical history, and environmental factors. Cases were prevalent IPMNs seen at the participating units within an 18-month timeframe. Matched controls were enrolled alongside patients seen at outpatient clinics.

RESULTS

Three-hundred and ninety patients with IPMN and 390 matched controls (166 males, mean age 65 in each group) were enrolled. Of the IPMNs, 310 had branch-duct involvement and 80 main-duct involvement. The only cancer with a 1st degree family history significantly higher in IPMN was pancreatic ductal adenocarcinoma (PDAC) (5.4% vs. 1.5%). Previous history of diabetes (13.6% vs. 7.5%), chronic pancreatitis (CP) (3.1% vs. 0.3%), peptic ulcer (7.2% vs. 4.3%), and insulin use (4.9% vs. 1.1%) were all more frequent with IPMNs. Logistic regression multivariate analysis revealed that history of diabetes (odds ratio (OR): 1.79, confidence interval (CI) 95%: 1.08-2.98), CP (OR: 10.10, CI 95%: 1.30-78.32), and family histories of PDAC (OR: 2.94, CI 95%: 1.17-7.39) were all independent risk factors. However, when analysis was restricted to diabetics who had taken insulin, risk of IPMN became stronger (OR: 6.03, CI 95%: 1.74-20.84). The association with all these risk factors seemed stronger for the subgroup with main duct involvement.

CONCLUSIONS

A previous history of diabetes, especially with insulin use, CP, and family history of PDAC are all relevant risk factors for the development of IPMN. These results suggest an overlap between certain risk factors for PDAC and IPMN.

Duration of diabetes and pancreatic cancer in a case-control study in the Midwest and the Iowa Women's Health Study (IWHS) cohort

CONTEXT

Studies have shown a relationship between history of diabetes and the risk of pancreatic cancer; however, the temporal relation between diabetes and pancreatic cancer is not clearly established.

OBJECTIVES

Diabetes and diabetes duration were examined in relation to pancreatic cancer in a population-based case-control study and prospective cohort.

METHODS

Case-control study: pancreatic cancer cases (n=200) from the Midwest were frequency matched by age and sex to population controls (n=673). Logistic regression yielded odds ratios (ORs) and 95% confidence intervals (95% CI). Iowa Women's Health Study (IWHS) cohort: 292 incident pancreatic cancer cases occurred between 1986-2008 among 36,084 post-menopausal, initially cancer-free women. Diabetes status and diagnosis age were ascertained at baseline and follow-ups. Proportional hazards regression yielded hazard ratios (HR, 95% CI) for pancreatic cancer in relation to baseline diabetes. Time-dependent analyses accounted for diabetes diagnosed after baseline. A nested-case control analysis assessed diabetes duration as a risk factor.

RESULTS

In the case-control study, compared to participants without diabetes, the multivariate ORs (95% CI) for pancreatic cancer were 2.35 (1.24-4.47) for those with diabetes and 4.00 (0.94-16.9), 2.79 (0.97-8.04), and 2.40 (0.97-5.98) for diabetes durations of 2-5 years, 5.1-10 years, and more than 10 years, respectively. In IWHS, compared to no diabetes, multivariate-adjusted HRs for pancreatic cancer were 1.86 (1.23-2.83) for baseline diabetes and 1.94 (1.40-2.69) adding diabetes during follow-up. In an IWHS nested case-control analysis, ORs were 1.70 (0.78-3.67), 2.62 (1.48-4.65), and 2.10 (1.36-3.24) for diabetes durations of 2-5 years, 5.1-10 years and more than 10 years, respectively, versus no diabetes.

CONCLUSIONS

Diabetes is associated with pancreatic cancer risk and this is similar across different duration categories.

Metformin-mediated growth inhibition involves suppression of the IGF-I receptor signalling pathway in human pancreatic cancer cells

Background

Epidemiological studies have shown direct associations between type 2 diabetes and obesity, both conditions associated with hyperglycaemia and hyperinsulinemia, and the risk of pancreatic cancer. Up to 80% of pancreatic cancer patients present with either new-onset type 2 diabetes or impaired glucose tolerance at the time of diagnosis. Recent population studies indicate that the incidence of pancreatic cancer is reduced among diabetics taking metformin. In this study, the effects of exposure of pancreatic cancer cells to high glucose levels on their growth and response to metformin were investigated.

Methods

The human pancreatic cancer cell lines AsPC-1, BxPC-3, PANC-1 and MIAPaCa-2 were grown in normal (5 mM) or high (25 mM) glucose conditions, with or without metformin. The influence by metformin on proliferation, apoptosis and the AMPK and IGF-IR signalling pathways were evaluated in vitro.

Results

Metformin significantly reduced the proliferation of pancreatic cancer cells under normal glucose conditions. Hyperglycaemia however, protected against the metformin-induced growth inhibition. The anti-proliferative actions of metformin were associated with an activation of AMP-activated protein kinase AMPK^Thr172 together with an inhibition of the insulin/insulin-like growth factor-I (IGF-I) receptor activation and downstream signalling mediators IRS-1 and phosphorylated Akt. Furthermore, exposure to metformin during normal glucose conditions led to increased apoptosis as measured by poly(ADP-ribose) polymerase (PARP) cleavage. In contrast, exposure to high glucose levels promoted a more robust IGF-I response and Akt activation which correlated to stimulated AMPK^Ser485 phosphorylation and impaired AMPK^Thr172 phosphorylation, resulting in reduced anti-proliferative and apoptotic effects by metformin.

Conclusion

Our results indicate that metformin has direct anti-tumour activities in pancreatic cancer cells involving AMPK^Thr172 activation and suppression of the insulin/IGF signalling pathways. However, hyperglycaemic conditions enhance the insulin/IGF-I responses resulting in an altered AMPK activation profile and prevent metformin from fully switching off the growth promoting signals in pancreatic cancer cells.

Usefulness of MALDI-TOF/MS identification of low-MW fragments in sera for the differential diagnosis of pancreatic cancer

OBJECTIVES

To identify new biomarkers of pancreatic cancer (PaCa), we performed MALDI-TOF/MS analysis of sera from 22 controls, 51 PaCa, 37 chronic pancreatitis, 24 type II diabetes mellitus (DM), 29 gastric cancer (GC), and 24 chronic gastritis (CG).

METHODS

Sera were purified by Sep-Pak C18 before MALDI-TOF/MS Anchorchip analysis.

RESULTS

Features present in at least 5% of all spectra were selected (n = 160, m/z range, 1200-5000). At univariate analysis, 2 features (m/z 2049 and 2305) correlated with PaCa, 3 (m/z 1449, 1605, and 2006) with DM. No feature characterized gastric cancer or chronic gastritis. Ten-fold cross-validation binary recursive partitioning trees were obtained for patients' classification. The tree (CA 19-9, age, m/z 2006, 2599, 2753, and 4997), built considering only patients with diabetes, allowed a distinction between DM [area under the receiver operating characteristic curve (AUC), 0.997], chronic pancreatitis (AUC, 0.968), and PaCa (AUC, 0.980), with an overall correct classification rate of 89%. The tree including CA 19-9, 1550, and 2937 m/z features, achieved an AUC of 0.970 in distinguishing localized from advanced PaCa. MALDI-TOF-TOF analysis revealed the 1550 feature as a fragment of Apo-A1, which was determined as whole protein and demonstrated to be closely correlated with PaCa.

CONCLUSIONS

The findings made demonstrate a role for serum peptides identified using MALDI-TOF/MS for addressing PaCa diagnosis.

ABO blood type, long-standing diabetes, and the risk of pancreatic cancer

AIM: To retrospectively study pancreatic cancer patients with respect to their ABO blood type and diabetes.

METHODS: Our analysis included a cohort of 1017 patients with pancreatic ductal cancer diagnosed at our hospital in Tokyo. They were divided into two groups: 114 patients with long-standing type 2 diabetes (DM group, defined as diabetes lasting for at least three years before the diagnosis of pancreatic cancer) and 903 patients without diabetes (non-DM group). Multivariate analysis was performed to identify factors that are associated with long-standing diabetes. The DM group was further divided into three subgroups according to the duration of diabetes (3-5 years, 5.1-14.9 years, and 15 years or more) and univariate analyses were performed.

RESULTS: Of the 883 pancreatic cancer patients with serologically assessed ABO blood type, 217 (24.6%) had blood type O. Compared with the non-DM group, the DM group had a higher frequency of blood type B [odds ratio (OR) = 2.61, 95%CI: 1.24-5.47; reference group: blood type A]. Moreover, male (OR = 3.17, 95%CI: 1.67-6.06), older than 70 years of age (OR = 2.19, 95%CI: 1.20-3.98) and presence of a family history of diabetes (OR = 6.21, 95%CI: 3.38-11.36) were associated with long-standing type 2 diabetes. The mean ages were 64.8 ± 9.2 years, 67.1 ± 9.8 years, and 71.7 ± 7.0 years in the subgroups with the duration of diabetes, 3-5 years, 5.1-14.9 years, and 15 years or more, respectively (P = 0.007). A comparison of ABO blood type distribution among the subgroups also showed a significant difference (P = 0.03).

CONCLUSION: The association of pancreatic cancer with blood type and duration of diabetes needs to be further examined in prospective studies.

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.

Type 2 diabetes mellitus and pancreatic cancer

Tumorigenesis of pancreatic cancer (PC) and the pathophysiology of type 2 diabetes mellitus (DM2) are emerging as intertwined pathways. As the operative morbidity and mortality of pancreatectomy has improved, incidence has increased and survival has remained mostly unchanged. The diagnosis of DM2 suggests pancreatic dysfunction and possible early carcinogenesis. DM2 is a significant comorbidity predicting worse outcomes in patients undergoing pancreatic resection as part of the treatment of PC. This article examines this phenomena and suggests possible approaches to screening and diagnosis.

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.

Anti-diabetic medications and risk of pancreatic cancer in patients with diabetes mellitus: a systematic review and meta-analysis

OBJECTIVES

Several preclinical and observational studies have shown that anti-diabetic medications (ADMs) may modify the risk of pancreatic cancer (PaC). We performed a systematic review and meta-analysis evaluating the effect of metformin, sulfonylureas (SUs), thiazolidinediones (TZDs), and insulin on the risk of PaC in patients with diabetes mellitus (DM).

METHODS

We conducted a systematic search of Medline, EMBASE, and Web of Science, up to June 2012, and published abstracts from major gastroenterology and oncology meetings from 2003 to 2012. Studies were included if they (1) evaluated and clearly defined exposure to metformin, SU, TZDs, and/or insulin, (2) reported PaC outcomes in patients with DM and (3) reported relative risks or odds ratio (OR) or provided data for their estimation. Summary OR estimates with 95% confidence intervals (CIs) were estimated using the random-effects model.

RESULTS

Eleven studies (6 cohort, 3 case-control, and 2 randomized controlled trials (RCTs)) reported 1770 cases of PaC in 730,664 patients with DM. Meta-analysis of observational studies showed no significant association between metformin (n=9 studies; adjusted OR 0.76, 95% CI 0.57-1.03, P=0.073), insulin (n=7 studies; adjusted OR 1.59, 95% CI 0.85-2.96, P=0.144), or TZD (n=4 studies; adjusted OR 1.02, 95% CI 0.81-1.30, P=0.844) use and risk of developing PaC. Use of SU was associated with a 70% increase in the odds of PaC (n=8 studies; adjusted OR 1.70, 95% CI 1.27-2.28, P<0.001). There was considerable inherent heterogeneity between studies not explained by study design, setting, or comparator drug and is likely related to confounding by indication and reverse causality. The pooled analyses of the two RCTs were underpowered and provided non-significant results with wide, non-informative 95% CIs.

CONCLUSIONS

Although SU seems to be associated with increased risk of PaC, meta-analysis of existing studies does not support a protective or harmful association between ADM use and risk of PaC in patients with DM. There was considerable heterogeneity across studies, and future, well-designed, prospective studies would be required to understand this association better.

Neutrophil gelatinase-associated lipocalin, macrophage inhibitory cytokine 1, and carbohydrate antigen 19-9 in pancreatic juice: pathobiologic implications in diagnosing benign and malignant disease of the pancreas

OBJECTIVE

Pancreatic diseases pose significant diagnostic challenge as signs and symptoms often overlap. We investigated the potential of pancreatic juice neutrophil gelatinase-associated lipocalin, macrophage inhibitory cytokine 1 (MIC-1), and carbohydrate antigen 19-9 (CA19-9) to aid in the diagnosis of patients with symptoms suggestive of pancreatic diseases.

METHODS

A total of 105 chronic pancreatitis (CP), pancreatic cancer (PC), and nonpancreatic nonhealthy (patients with symptoms mimicking pancreatic disease but found to be free of any pancreatic disease) patients underwent endoscopic pancreatic juice collection after secretin stimulation. Neutrophil gelatinase-associated lipocalin and MIC-1 levels were measured by enzyme-linked immunosorbent assay, whereas CA19-9 was measured by radioimmunoassay.

RESULTS

Neutrophil gelatinase-associated lipocalin, MIC-1, and CA19-9 were significantly elevated in the pancreatic juice of patients with CP and patients with PC as compared with nonpancreatic nonhealthy controls (P ≤ 0.034). Neutrophil gelatinase-associated lipocalin seemed most promising in differentiating diseased versus nondiseased pancreata (areas under the curve, 0.88-0.91), whereas MIC-1 was found to be higher in patients with PC than in patients with CP (P = 0.043). Interestingly, MIC-1 levels in diabetic patients with PC were higher than in nondiabetic patients with PC (P = 0.030) and diabetic patients with CP (P = 0.087). Carbohydrate antigen 19-9 showed the least ability to distinguish patient groups (areas under the curve, 0.61-0.76).

CONCLUSIONS

Pancreatic juice neutrophil gelatinase-associated lipocalin shows potential utility in establishing pancreatic etiology in the context of nonspecific symptoms, whereas MIC-1 may aid in differentiating PC from CP.

A novel serum metabolomics-based diagnostic approach to pancreatic cancer

BACKGROUND

To improve the prognosis of patients with pancreatic cancer, more accurate serum diagnostic methods are required. We used serum metabolomics as a diagnostic method for pancreatic cancer.

METHODS

Sera from patients with pancreatic cancer, healthy volunteers, and chronic pancreatitis were collected at multiple institutions. The pancreatic cancer and healthy volunteers were randomly allocated to the training or the validation set. All of the chronic pancreatitis cases were included in the validation set. In each study, the subjects' serum metabolites were analyzed by gas chromatography mass spectrometry (GC/MS) and a data processing system using an in-house library. The diagnostic model constructed via multiple logistic regression analysis in the training set study was evaluated on the basis of its sensitivity and specificity, and the results were confirmed by the validation set study.

RESULTS

In the training set study, which included 43 patients with pancreatic cancer and 42 healthy volunteers, the model possessed high sensitivity (86.0%) and specificity (88.1%) for pancreatic cancer. The use of the model was confirmed in the validation set study, which included 42 pancreatic cancer, 41 healthy volunteers, and 23 chronic pancreatitis; that is, it displayed high sensitivity (71.4%) and specificity (78.1%); and furthermore, it displayed higher sensitivity (77.8%) in resectable pancreatic cancer and lower false-positive rate (17.4%) in chronic pancreatitis than conventional markers.

CONCLUSIONS

Our model possessed higher accuracy than conventional tumor markers at detecting the resectable patients with pancreatic cancer in cohort including patients with chronic pancreatitis.

IMPACT

It is a promising method for improving the prognosis of pancreatic cancer via its early detection and accurate discrimination from chronic pancreatitis.

Prevalence of diabetes mellitus in pancreatic cancer compared to common cancers

OBJECTIVES

In pancreatic cancer (PaC), the prevalence of diabetes mellitus (DM), especially new-onset DM (≤36 months of PaC diagnosis), is high. To determine if this observation is unique to PaC, we compared the prevalence and characteristics of DM in lung, breast, prostate, and colorectal cancers with PaC and noncancer controls.

METHODS

We retrospectively reviewed the medical records of 500 consecutive patients with cancer (100 each with lung, breast, prostate, and colorectal cancers and PaC) and 100 noncancer controls.

RESULTS

Patients with PaC (mean age ± SD, 71.6 ± 9.4 years; 53% men) had a significantly (P < 0.0001) higher prevalence of DM (68%) compared to age-matched patients with lung (mean age ± SD, 71.6 ± 9.4 years; 59% men; and 19.6% DM), breast (mean age ± SD, 71.6 ± 9.6 years; 100% women; and 19.4% DM), prostate (mean age ± SD, 71.3 ± 9.4 years; 100% men; and 14.8% DM), and colorectal cancer (mean age ± SD, 71.6 ± 9.5 years; 56% men; and 20.7% DM), and noncancer controls (mean age ± SD, 70.7 ± 9.2 years; 57% men; and 23.5% DM). Among the patients with PaC, 40% developed DM in the 36 months preceding the diagnosis of PaC compared with 3.3% to 5.7% in the other groups (P < 0.0001).

CONCLUSIONS

Whereas the prevalence of DM in PaC is very high, DM prevalence in other common cancers is no different from that in noncancer controls. In particular, new-onset DM is a phenomenon that is unique to PaC.

Upregulation of transgelin is an independent factor predictive of poor prognosis in patients with advanced pancreatic cancer

Transgelin is a known actin-binding protein, which plays a role in regulating the functions of smooth muscle cells or fibroblasts. Recent evidence indicates that transgelin is involved in diverse human cancers, yet its role in pancreatic cancer remains unclear. We therefore evaluated the expression characteristics and function of transgelin in pancreatic cancer. Immunohistochemical analysis of benign (n = 30 patients) and malignant (n = 114 patients) pancreatic ductal cells showed significantly higher transgelin staining in malignant cells. Lymph node metastasis (P = 0.026) and diabetes (P = 0.041) were shown to significantly correlate with transgelin protein expression. Patients with high transgelin expression showed a shorter 5-year overall survival and a lower tumor-specific survival than those with low transgelin expression. Multivariate analysis revealed that transgelin was an independent factor affecting pancreatic tumor-specific survival (P = 0.025). In vitro, RNA interference-mediated transgelin knockdown resulted in inhibition of pancreatic cancer cell proliferation, migration and invasion. Depletion of transgelin expression could suppress pancreatic tumorigenicity and tumor growth in vivo, and produce enhanced cytotoxic effects of gemcitabine on pancreatic cancer cells both in vitro and in vivo. Our results indicate that transgelin plays a promoting role in tumor progression, and appears to be a novel prognostic marker for advanced pancreatic cancer.

Molecular markers in pancreatic cancer diagnosis

Pancreatic ductal adenocarcinoma (PDAC) represents a fatal neoplasia with a high mortality rate. Effective early detection methods are needed since this is the best way to cure this disease. During the last several years, many investigations focused on determining relevant biomarkers that may be present during early stages of pancreatic tumor development. Although several biomarkers have been proposed for pancreatic cancer detection, the clinical applicability has been confusing. Currently, although CA19-9 is one test used, the sensitivity and specificity for the disease are less than optimal. Here, we review several new potential serum, plasma and stool markers that are currently under evaluation. Although these have not been sufficiently validated for routine clinical use, these markers could prove valuable with further investigations. We keep the hope that a combination of some of these novel biomarkers can be a useful tool for early PDAC diagnosis before image techniques and/or patient's symptoms reveal disease in an incurable state.

Personalizing pancreatic cancer medicine: what are the challenges?

The P4 paradigm for future medicine promises changes in cancer management with improved Prediction of treatment response, Prevention of disease, Personalization of therapy, and Participation by patients. Significant challenges remain for the implementation of the P4 principles for pancreatic cancer, but many strides have been made in the past several years that should facilitate a future in which the disease can be detected at earlier stages and treatments can be customized to target features of a particular patient’s disease. This article summarizes the basic molecular biology of pancreatic tumors and the current state of pancreatic cancer treatment, as well as targeted treatments in the pipeline that might enable future personalized pancreatic cancer treatment and prediction of response to treatment. It also discusses possible directions for screening patients at high risk of developing the disease, detecting tumors at earlier stages, and increasing patient involvement in designing treatment.

New-onset diabetes with a history of dyslipidemia predicts pancreatic cancer

OBJECTIVE

This study aimed to investigate whether the reported relationship between diabetes and pancreatic cancer (PC) could result from detection bias and whether dyslipidemia and/or new-onset diabetes (diagnosed within 1 year) could predict PC.

METHODS

A random sample of 1 million subjects covered by National Health Insurance was recruited. From 2003 to 2005, 495,493 men and 503,901 women without PC were followed up. Cox regression was used to evaluate the adjusted relative risk considering potential PC detection examinations and covariates.

RESULTS

Diabetic patients had a significantly higher probability of receiving examinations that might lead to PC diagnosis. In Cox proportional hazards regression models, diabetes was not a significant predictor, but dyslipidemia was significantly associated with an approximately 40% higher risk of PC. Age, living in more urbanized regions, and potential PC detection examinations were significant covariates. Patients with new-onset diabetes and previous dyslipidemia had a remarkably higher risk compared with those without either condition (relative risk [95% confidence interval], 2.512 [1.169-5.398]).

CONCLUSIONS

Dyslipidemia, but not diabetes, is a significant risk factor for PC. The link between diabetes and PC is likely due to confounders and detection bias. Patients with new-onset diabetes and a history of dyslipidemia are at an especially high risk of PC.

Clinical value of circulating lipocalins and insulin-like growth factor axis in pancreatic cancer diagnosis

OBJECTIVES

Early diagnosis of pancreatic cancer (PC) in diabetic patients is difficult owing to late presentation of symptoms. Hence, finding a marker to identify cancer stage early would be useful to improve survival. We aimed to determine levels of serum retinol binding protein 4 (RBP-4), neutrophil gelatinase-associated lipocalin (NGAL), insulin-like growth factor I (IGF-I), and its binding protein 3 (IGFBP-3) in patients with PC with preexisting type 2 diabetes. Moreover, we assessed their clinical usefulness in PC diagnosis and their association with tumor severity.

METHODS

Twenty-three patients with PC, 32 diabetic patients, and 20 healthy controls were examined. Preoperative and postoperative samples were obtained from 15 patients with PC. Serum insulin, cancer antigen (CA 19-9), RBP-4, NGAL, IGF-I, and IGFBP-3 levels were estimated by enzyme-linked immunosorbent assay.

RESULTS

Significant elevation in the levels of RBP-4 (60.1 [46.3-71.4] ng/mL), NGAL (142 [80-235] ng/mL), and IGF-I (174 [9.3] ng/mL) together with significant reduction in the level of IGFBP-3 (3669 [299] ng/mL) was found in patients with PC. Moreover, RBP-4 and NGAL levels were reduced in postoperative samples compared with preoperative ones. Receiver operating characteristic curve analysis revealed that they can distinguish PC from non-PC cases with significant area under the curve.

CONCLUSIONS

Retinol binding protein 4, NGAL, IGF-I, and IGFBP-3 are associated with PC in type 2 diabetic patients. They could be useful in distinguishing PC from non-PC cases when used in combination or with cancer antigen.

A very low carbohydrate ketogenic diet prevents the progression of hepatic steatosis caused by hyperglycemia in a juvenile obese mouse model

Objective:

To investigate whether the improvement in hyperglycemia by dietary control influences hyperglycemia-induced pathologies in tissues of juvenile obese (ob/ob) mice.

Design:

Five-week-old ob/ob mice were fed a very low carbohydrate ketogenic diet (KD) for 7 weeks. The blood glucose levels and body weight were monitored during this period. Biochemical parameters in the serum and tissue pathologies of the mice were analyzed at the end of the 7-week period.

Results:

The hyperglycemic phenotype of the ob/ob mice was improved by KD feeding for 7 weeks. Surprisingly, we found that KD feeding also drastically reduced the hepatic steatosis phenotype in ob/ob mice, while their obesity phenotype was unaltered. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that several proteins found in the liver of ob/ob mice fed a regular chow diet were undetectable after being fed KD. Liquid chromatography with tandem mass spectrometry (LC-MS/MS) MASCOT search and western blot analysis revealed that the proteins absent from the mice fed KD included fatty acid synthase (FAS) and acetyl-CoA carboxylase 1 (ACC1), which are key enzymes for lipogenesis in the liver. Fatty acid analysis supported the results because the ratio of C18:1, which is a major product of lipogenesis, was reduced by KD feeding. However, C18:2, which cannot be synthesized in mammalian cells but is present in the KD, was found to be a major component in the liver of KD-fed ob/ob mice.

Conclusion:

Hyperglycemia promotes hepatic steatosis via the lipogenic pathway in the liver of juvenile ob/ob mice. However, the development of steatosis is prevented by feeding KD owing to an improvement in hyperglycemia. We found that the progression of steatosis is reflected by the composition of fatty acids in the total lipids of the liver and serum.

Early diagnosis of pancreatic cancer: challenges and new developments

Pancreatic cancer is a lethal malignancy with its incidence almost equivalent to mortality. The complex pathophysiology, absence of early diagnostic and prognostic markers and unresponsiveness to radiation and chemotherapies are major barriers against successful therapy. Poor performance of therapeutic agents, even in the initial stage of invasive cases, emphasizes the importance of early detection for improved survival. The present review discusses the challenges and advances in biomarkers including serological signatures, circulating tumor cells, autoantibodies, epigenetic markers and miRNAs that are being explored to detect this cancer at early stages. Considering the long time gap between the development of malignant lesions and full-blown primary and metastatic pancreatic cancer, unique opportunities are being contemplated for the development of potential diagnostic and prognostic markers.

Diabetes and pancreatic cancer

Epidemiological studies clearly indicate that the risk of pancreatic cancer (PC) is increased in diabetic patients, but most studies focus on overall diabetes or type 2 diabetes mellitus (T2DM), and there are few studies on the risks of type 1 and type 3c (secondary) diabetes. Possible mechanisms for increased cancer risk in diabetes include cellular proliferative effects of hyperglycemia, hyperinsulinemia, and abnormalities in insulin/IGF receptor pathways. Recently, insulin and insulin secretagogues have been observed to increase the PC risk, while metformin treatment reduces the cancer risk in diabetic subjects. In addition, anticancer drugs used to treat PC may either cause diabetes or worsen coexisting diabetes. T3cDM has emerged as a major subset of diabetes and may have the highest risk of pancreatic carcinoma especially in patients with chronic pancreatitis. T3cDM is also a consequence of PC in at least 30% of patients. Distinguishing T3cDM from the more prevalent T2DM among new-onset diabetic patients can be aided by an assessment of clinical features and confirmed by finding a deficiency in postprandial pancreatic polypeptide release. In conclusion, diabetes and PC have a complex relationship that requires more clinical attention. The risk of developing PC can be reduced by aggressive prevention and treatment of T2DM and obesity and the prompt diagnosis of T3cDM may allow detection of a tumor at a potentially curable stage.

Strategies for discovering novel pancreatic cancer biomarkers

Pancreatic ductal adenocarcinoma (PDAC) is the fourth leading cause of cancer-related deaths in both men and women in Canada and the United States and has the most dismal survival rates among any solid malignancy. Most patients are diagnosed with pancreatic cancer once the disease has progressed into an advanced or metastatic stage, making the only curative approach of resection surgery impossible. The persistent delayed or missed diagnosis of pancreatic cancer can be attributed to the absence of early symptoms and the lack of efficient non-invasive screening or diagnostic tests in clinical practice. Given that earlier diagnosis is critical for ameliorating patients' survival rates, there is an urgent need for biomarkers with enough sensitivity and specificity to help diagnose pancreatic cancer early. Serological biomarkers provide a minimally invasive and efficient way of detecting pancreatic cancer, however, there is currently no marker with sufficient diagnostic sensitivity and specificity to identify early cancer patients. This review focuses on the classical tumor markers for PDAC as well as emerging markers. In addition, we will discuss an integrative proteomic approach used in our lab to identify a panel of biomarkers that have the potential to allow the early detection of PDAC.This article is part of a Special Issue entitled: From protein structures to clinical applications.

Research on the relationships between pancreatic cancer and hyperglycemia in Chinese populations

Aims/Introduction

Pancreatic cancer (PC) is related to diabetes. Long‐standing diabetes should be a prerequisite, whereas new‐onset hyperglycemia might be a result of PC. However, the association between diabetes and PC is still in dispute.

Materials and Methods

We investigated the relationship between glucose metabolism and other factors by retrospectively analyzing the clinical data of 331 PC patients. Any histopathological type was eligible. The patients were divided into three groups: group A, normal glucose metabolism; group B, hyperglycemia duration≤6 months; and group C, diabetes duration >24 months.

Results

The prevalence of hyperglycemia was 59.5%. Most patients were diagnosed with diabetes mellitus either concomitantly with cancer (39.0%) or within 6 months before cancer diagnosis (6.9%). There were more females in group C than group A (P = 0.005) and B (P = 0.018). Patients in group A were younger (A vs B, P < 0.001; A vs C, P = 0.032) and thinner (A vs B, P = 0.013; A vs C, P = 0.027). In group C, more individuals shared a family history of diabetes (A vs C, P = 0.004; B vs C, P = 0.023), but fewer smoked (A vs C, P = 0.027; B vs C, P = 0.020). Patients in group C had a larger proportion of poorly differentiated cancer (A vs C, P = 0.002; B vs C, P = 0.012). No differences in glucose metabolism were found among the different histological types.

Conclusions

We further support the notion that diabetes duration >24 months might not be cancer related. Older and fatter PC patients were more likely to develop hyperglycemia. More patients with long‐standing diabetes had poor tumor differentiation. We speculate that smoking and alcohol intake might advance PC onset.

The bidirectional interation between pancreatic cancer and diabetes

The bidirectional interation between pancreatic cancer (PanCa) and diabetes has been confirmed by epidemiological studies, which provide evidence-based medical support for further research into the mechanisms involved in the interaction. We reviewed the literature regarding the role of diabetes in the generation and progression of PanCa and the mechanism by which PanCa induces diabetes for its malignant progression. The effect of antidiabetic drugs on the occurrence and prognosis of PanCa was also reviewed. Diabetes may directly promote the progression of PanCa by pancreatic duct enlargement and hypertension, as well as by enabling an increased tumor volume. Hyperinsulinemia, insulin resistance, cytokines, hyperglycemia and genotype change are also important factors in the progression of PanCa with diabetes. Hyperglycemia may be the first clinical manifestation and is helpful in the early diagnosis of PanCa. Furthermore, antidiabetic drugs can have different effects on the occurrence and prognosis of PanCa. The bidirectional interation between PanCa and diabetes is involved in the occurrence, proliferation, invasion, metastasis and prognosis of PanCa with diabetes. The discovery of biomarkers for the early diagnosis of PanCa, as well as the novel usage of metformin for its antitumor effects and determining the potential mechanisms of these effects, may be the next direction for PanCa research and treatment.

PAM4 enzyme immunoassay alone and in combination with CA 19-9 for the detection of pancreatic adenocarcinoma

BACKGROUND

The monoclonal antibody PAM4 has high specificity for pancreatic ductal adenocarcinoma (PDAC), as well as its precursor lesions, but has not been found to be reactive with normal and benign pancreatic tissues. The objective of the current study was to evaluate a PAM4-based serum enzyme immunoassay alone and in combination with the carbohydrate antigen (CA) 19-9 assay for the detection of PDAC, with particular attention to early stage disease.

METHODS

Sera from patients with confirmed PDAC (N = 298), other cancers (N = 99), benign disease of the pancreas (N = 120), and healthy adults (N = 79) were evaluated by a specific enzyme immunoassay for the concentration of PAM4 and CA 19-9 antigen levels by blinded analyses. All tests for statistical significance were 2-sided.

RESULTS

The overall sensitivity for PAM4 detection of PDAC was 76%, with 64% of patients with stage I disease also identified. The detection rate was considerably higher (85%) for patients with advanced disease. The assay demonstrated high specificity compared with benign pancreatic disease (85%), with a positive likelihood ratio of 4.93. CA 19-9 provided an overall sensitivity of 77%, and was positive in 58% of patients with stage I disease; however, the specificity was significantly lower for CA 19-9 (68%), with a positive likelihood ratio of 2.85 (P = .026 compared with PAM4). It is important to note that a combined PAM4 and CA 19-9 biomarker serum assay demonstrated an improved sensitivity (84%) for the overall detection of PDAC without a significant loss of specificity (82%) compared with either arm alone.

CONCLUSIONS

The PAM4 enzyme immunoassay identified approximately two-thirds of patients with stage I PDAC with high discriminatory power with respect to benign, nonneoplastic pancreatic disease. These results provide a rationale for testing patient groups considered to be at high risk for PDAC with a combined PAM4 and CA 19-9 biomarker serum assay for the detection of early stage PDAC.

New-onset diabetes patients need pancreatic cancer screening?

OBJECTIVE

Because patients with new-onset diabetes mellitus (DM) have a significantly increased likelihood of association with pancreatic cancer, we need to select the subgroup of diabetic patients who have more chance of association with pancreatic cancer.

METHODS

We retrospectively reviewed medical records of case group (151 patients with pancreatic cancer with new-onset DM) and control group (302 patients with new-onset DM without cancer).

RESULTS

Compared with the control group, pancreatic cancer group were older, had more weight loss, lower usual body mass index (BMI), more family history of pancreatic cancer (3.3% vs. 0.7%; P=0.044), and had less family history of DM (13.9% vs. 37.4%; P<0.001). If a new-onset DM patient did not have family history of DM, he was of age older than or equal to 65 years or had weight loss of >2 kg or had premorbid usual BMI <25 kg/m(2), pancreatic cancer associated DM could be discriminated from new-onset type 2 DM with 80.8% sensitivity, 67.6% specificity, 2.5% and 99.7% of positive and negative predictability for pancreatic cancer, respectively.

CONCLUSIONS

Among patients who meet criteria for diabetes within 2 years, those who are elderly, have lower premorbid BMI, weight loss, no family history of DM, need screening of pancreatic cancer.

Identification of serum biomarker signatures associated with pancreatic cancer

Pancreatic cancer is an aggressive disease with poor prognosis, due, in part, to the lack of disease-specific biomarkers that could afford early and accurate diagnosis. With a recombinant antibody microarray platform, targeting mainly immunoregulatory proteins, we screened sera from 148 patients with pancreatic cancer, chronic pancreatitis, autoimmune pancreatitis (AIP), and healthy controls (N). Serum biomarker signatures were derived from training cohorts and the predictive power was evaluated using independent test cohorts. The results identified serum portraits distinguishing pancreatic cancer from N [receiver operating characteristics area under the curve (AUC) of 0.95], chronic pancreatitis (0.86), and AIP (0.99). Importantly, a 25-serum biomarker signature discriminating pancreatic cancer from the combined group of N, chronic pancreatitis, and AIP was determined. This signature exhibited a high diagnostic potential (AUC of 0.88). In summary, we present the first prevalidated, multiplexed serum biomarker signature for diagnosis of pancreatic cancer that may improve diagnosis and prevention in premalignant diseases and in screening of high-risk individuals.

The pathobiological impact of cigarette smoke on pancreatic cancer development (review)

Despite extensive efforts, pancreatic cancer remains incurable. Most risk factors, such as genetic disposition, metabolic diseases or chronic pancreatitis cannot be influenced. By contrast, cigarette smoking, an important risk factor for pancreatic cancer, can be controlled. Despite the epidemiological evidence of the detrimental effects of cigarette smoking with regard to pancreatic cancer development and its unique property of being influenceable, our understanding of cigarette smoke-induced pancreatic carcinogenesis is limited. Current data on cigarette smoke-induced pancreatic carcinogenesis indicate multifactorial events that are triggered by nicotine, which is the major pharmacologically active constituent of tobacco smoke. In addition to nicotine, a vast number of carcinogens have the potential to reach the pancreatic gland, where they are metabolized, in some instances to even more toxic compounds. These metabolic events are not restricted to pancreatic ductal cells. Several studies show that acinar cells are also greatly affected. Furthermore, pancreatic cancer progenitor cells do not only derive from the ductal epithelial lineage, but also from acinar cells. This sheds new light on cigarette smoke-induced acinar cell damage. On this background, our objective is to outline a multifactorial model of tobacco smoke-induced pancreatic carcinogenesis.

Early diagnosis of pancreatic adenocarcinoma: role of stroma, surface proteases, and glucose-homeostatic agents

OBJECTIVES

New-onset diabetes in pancreatic adenocarcinoma is due to a combination of insulin resistance and decreased β-cell function. Its differentiation from the common type 2 diabetes is the prerequisite for early diagnosis of pancreatic adenocarcinoma. Little attention has been paid to pancreatic stroma and surface proteases.

METHODS

The activated fibroblasts selectively express fibroblast activation protein α, a structural homolog of the ubiquitously expressed dipeptidyl peptidase 4. Their role in pancreatic carcinogenesis is reviewed.

RESULTS

Homodimers and heterodimers of both enzymes display high specificity for peptides and proteins with penultimate proline or alanine. Most glucose-homeostatic agents are candidate substrates of these enzymes. The biological activity of truncated substrates is decreased or absent.

CONCLUSIONS

The interactions of surface proteases with glucose-homeostatic agents may adequately explain the evolution of diabetes associated with pancreatic adenocarcinoma and differentiate it from the common type 2 diabetes.

Diabetes mellitus in pancreatic cancer patients in the Czech Republic: sex differences

Aims. The prevalence of diabetes mellitus in pancreatic cancer patients and control subjects was compared. Methods. Retrospective evaluation of 182 pancreatic cancer patients and 135 controls. The presence of diabetes was evaluated and the time period between the diagnosis of diabetes and pancreatic cancer was assessed. A subanalysis based on patient sex was conducted. Results. Diabetes mellitus was present in 64 patients (35.2%) in pancreatic cancer group and in 27 patients (20.0%) in control group (χ² = 8.709; P = 0.003). In 18 patients (28.1% of diabetic pancreatic cancer patients) diabetes was new-onset. Diabetes was new-onset in 23.3% of females compared to 38.1% of males (χ² = 1.537; P = 0.215). The overall prevalence of diabetes was significantly higher among female pancreatic cancer patients (25% versus 43.9%; χ² = 7.070, P = 0.008), while diabetes prevalence was equally represented in the control group patients (22.1% versus 17.2%; χ² = 0.484, P = 0.487). Conclusion. The prevalence of diabetes mellitus in study group of pancreatic cancer patients was significantly higher when compared to control group. Pancreatic cancer patients with diabetes were predominantly females, while diabetes was equally prevalent among sexes in the control group. Therefore, patient sex may play important role in the risk stratification.

Diabetes and cancer I: risk, survival, and implications for screening

Type 2 diabetes mellitus (DM) and cancer are common diseases that are frequently diagnosed in the same individual. An association between the two conditions has long been postulated. Here, we review the epidemiological evidence for increased risk of cancer, decreased cancer survival, and decreased rates of cancer screening in diabetic patients. The risk for several cancers, including cancers of the pancreas, liver, colorectum, breast, urinary tract, and endometrium, is increased in patients with DM. In a pooled risk analysis weighting published meta-analytic relative risk (RR) for individual cancer by differences in their incidence rates, we found a population RR of 0.97 (95 % CI, 0.75-1.25) in men and 1.29 (95 % CI, 1.16-1.44) in women. All meta-analyses showed an increased relative risk for cancer in diabetic men, except studies of prostate cancer, in which a protective effect was observed. The relationship between diabetes and cancer appears to be complex, and at present, a clear temporal relationship between the two conditions cannot be defined. DM also impacts negatively on cancer-related survival outcomes and cancer screening rates. The overwhelming evidence for lower cancer screening rates, increased incidence of certain cancers, and poorer prognosis after cancer diagnosis in diabetic patients dictates a need for improved cancer care in diabetic individuals through improved screening measures, development of risk assessment tools, and consideration of cancer prevention strategies in diabetic patients. Part two of this review focuses on the biological and pharmacological mechanisms that may account for the association between DM and cancer.

Pancreatic diabetes manifests when beta cell area declines by approximately 65% in humans

AIMS/HYPOTHESIS

Diabetes frequently develops in patients with pancreatic disorders. We aimed to determine the lower threshold of beta cell area for diabetes manifestation as well as the impact of insulin sensitivity on glucose homoeostasis in patients with pancreatic diabetes.

METHODS

Eighty-two patients undergoing pancreatic surgery underwent pre-operative oral glucose challenge. Fractional pancreatic beta cell area was determined, and indices of insulin sensitivity and beta cell function were calculated.

RESULTS

HbA1c and glucose levels were similar in patients with high and intermediate beta cell area, but were significantly higher in those with the lowest beta cell area (p < 0.0001). Insulin secretion was reduced only in patients with the lowest beta cell area (p < 0.001). The relative beta cell deficits at the onset of diabetes and impaired glucose tolerance were 64% and 21%, respectively, based on 2 h glucose levels. Deteriorating insulin sensitivity was associated with a small increase in the incidence of diabetes.

CONCLUSIONS/INTERPRETATION

In conclusion, pancreatic diabetes probably develops after a reduction in beta cell area of ~65%. Post-challenge glucose excursions are much more closely related to pancreatic beta cell area than to fasting glycaemia, thereby underlining the usefulness of the OGTT in patients with pancreatic disorders.

DJ-1, a novel biomarker and a selected target gene for overcoming chemoresistance in pancreatic cancer

PURPOSE

Aberrant expression of DJ-1 has been proven to be associated with tumorigenesis in many carcinomas. However, its role in pancreatic cancer is unknown. The aims of this study were to investigate whether the serum DJ-1 might be a potential biomarker for pancreatic cancer and to determine the biologic function of DJ-1 expression in gemcitabine-induced chemoresistance of pancreatic cancer.

METHODS

The serum level of DJ-1 was higher in 128 pancreatic cancer patients compared with 62 healthy controls by ELISA. To determine the effect of DJ-1 on pancreatic tumor chemoresistance, a siRNA-targeting DJ-1 was synthesized and a stably transfected cell line with DJ-1 over-expression was constructed. The mechanism of tumor chemoresistance was assessed by multiple methods, such as MTT assay, real-time PCR, Western blot and flow cytometry.

RESULTS

The serum level of DJ-1 was higher in pancreatic cancer patients than healthy controls, and it has the relationship with tumor differentiation in pancreatic cancer. Down-regulation of DJ-1 enhanced gemcitabine-induced apoptosis in three pancreatic cancer cell lines. On the contrary, over-expression of DJ-1 desensitized the MIA PaCa-2 to the induction of apoptosis by gemcitabine.

CONCLUSIONS

Our results suggest that the serum level of DJ-1 may be a potential biomarker for pancreatic cancer, and that DJ-1 plays critical roles in the pancreatic tumor chemoresistance, supporting the development of chemotherapeutic approaches targeting this oncogene.

Diabetes mellitus correlates with increased risk of pancreatic cancer: a population-based cohort study in Taiwan

BACKGROUND AND AIM

This study investigated whether diabetes mellitus (DM) increased the risk of pancreatic cancer and whether anti-diabetic drugs reduced the risk in Taiwan.

METHODS

We designed a population-based cohort study using the Taiwan National Health Insurance Database, which consisted of 49,803 patients aged 20 years and older with newly diagnosed DM as the diabetic group and 199,212 people without DM as the non-diabetic group during 1998-2007.

RESULTS

The incidence of pancreatic cancer was higher in patients with diabetic duration less than 2 years, as compared to the non-diabetic group (27.81 vs 6.96 per 10,000 person-years, 95% confidence interval = 2.11-7.54). Age (aged 40-64, hazard ratio [HR] = 5.22, and aged 65 and older, HR = 7.59, respectively), chronic pancreatitis (HR = 19.40), gallstones (HR = 2.56), and hepatitis C infection (HR = 3.08) were also significant factors predicting pancreatic cancer. Patients with concurrent DM and chronic pancreatitis had an appreciably elevated risk of developing pancreatic cancer (HR = 33.52), as compared with subjects without these comorbidities. The association was not statistically significant between use of anti-diabetic drugs and the risk of pancreatic cancer.

CONCLUSIONS

Diabetes < 2 years' duration is associated with pancreatic cancer and could be an early manifestation of pancreatic cancer. Long-standing diabetes was not found to be a risk factor for pancreatic cancer in Taiwan's patients. Old age, chronic pancreatitis, gallstones and hepatitis C infection are other risk factors for pancreatic cancer. These high-risk patients should undergo close follow-up programs for pancreatic cancer.

Use of antidiabetic agents and the risk of pancreatic cancer: a case-control analysis

OBJECTIVES

The objective of this study was to explore the association between use of metformin or other antidiabetic drugs, diabetes, and the risk of pancreatic cancer.

METHODS

We conducted a case-control study using the UK-based General Practice Research Database (GPRD). Cases had a first-time diagnosis of pancreatic cancer, and six controls per case were matched on age, sex, calendar time, general practice, and number of years of active history in the GPRD before the index date. Results were further adjusted in multivariate logistic regression analyses for potential confounders such as body mass index, smoking, alcohol consumption, and diabetes duration.

RESULTS

In all, 2,763 case patients with a recorded diagnosis of pancreatic cancer were identified. Mean age ± s.d. was 69.5 ± 11.0 years. Long-term use (≥ 30 prescriptions) of metformin was not associated with a materially altered risk of pancreatic cancer (adjusted odds ratio (adj. OR): 0.87, 95% confidence interval (CI): 0.59-1.29), but there was a suggestion of effect modification by gender, as long-term use of metformin was linked to a decreased risk in women (adj. OR: 0.43, 95% CI: 0.23-0.80). Both use of sulfonylureas (≥ 30 prescriptions, adj. OR: 1.90, 95% CI: 1.32-2.74) and of insulin (≥ 40 prescriptions, adj. OR: 2.29, 95% CI: 1.34-3.92) were associated with an increased risk of pancreatic cancer.

CONCLUSIONS

Use of metformin was associated with a decreased risk of pancreatic cancer in women only, whereas use of sulfonylureas and of insulin was associated with an increased risk of pancreatic cancer.

Multi-institutional analysis of pancreatic adenocarcinoma demonstrating the effect of diabetes status on survival after resection

BACKGROUND

The effect of diabetes on survival after resection pancreatic ductal carcinoma (PDAC) is unclear. The present study was undertaken to determine whether pre-operative diabetes has any predictive value for survival.

METHODS

A retrospective review from seven centres was performed. Metabolic factors, tumour characteristics and outcomes of patients undergoing resection for PDAC were collected. Univariate and multivariable analyses were performed to determine factors associated with disease-free (DFS) and overall survival (OS).

RESULTS

Of the 509 patients in the present study, 31.2% had diabetes. Scoring systems were devised to predict OS and DFS based on a training set (n= 245) and were subsequently tested on an independent set (n= 264). Pre-operative diabetes (P < 0.001), tumour size >2 cm (P= 0.001), metastatic nodal ratio >0.1 (P < 0.001) and R1 margin (P < 0.001) all correlated with DFS and OS on univariate analysis. Scoring systems were devised based on multivariable analysis of the above factors. Diabetes and the metastatic nodal ratio were the most important factors in each system, earning two points for OS and four points for DFS. These scoring systems significantly correlated with both DFS (P < 0.001) and OS (P < 0.001).

CONCLUSION

Pre-operative diabetes status provides useful information that can help to stratify patients in terms of predicted post-operative OS and DFS.

ABO blood type, diabetes and risk of gastrointestinal cancer in northern China

AIM: To explore the potential risk factors related to gastrointestinal cancer in northern China.

METHODS: A total of 3314 cases of gastrointestinal cancer (esophageal, gastric, pancreatic and biliary) and 2223 controls (including healthy individuals, glioma and thyroid cancer) were analyzed by case-control study. Multivariable logistic regression analysis was applied to evaluate the association between different cancers and hepatitis B surface antigen, sex, age, blood type, diabetes, or family history of cancer.

RESULTS: Type 2 diabetes was significantly associated with gastric, biliary and pancreatic cancer with an OR of 2.0-3.0. Blood type B was significantly associated with esophageal cancer [odd ratio (OR) = 1.53, 95% confidence interval (CI) = 1.10-2.14] and biliary cancer (OR = 1.49, 95% CI = 1.09-2.05). The prevalence of type 2 diabetes was significantly higher in gastric, biliary and pancreatic cancers compared with other groups, with ORs ranging between 2.0 and 3.0. Family history of cancer was strongly associated with gastrointestinal compared with other cancers.

CONCLUSION: Blood type B individuals are susceptible to esophageal and biliary cancer. Type 2 diabetes is significantly associated with gastric, biliary and especially pancreatic cancer.

Clinical profiles and long-term outcomes of patients with pancreatic ductal adenocarcinoma and diabetes mellitus

BACKGROUND

Diabetes mellitus (DM) is considered to be a possible risk factor and/or a manifestation of pancreatic ductal adenocarcinoma (PDAC). This study is aimed at analysing the potential association of diabetes mellitus with the development and pathogenic degrees of PDAC and post-surgical survival of Chinese Han PDAC patients.

METHODS

A total of 1123 patients with PDAC were recruited and included 256 patients with diabetes mellitus within 2 years (new-onset) and 62 patients with diabetes mellitus ≥ 2 years (long-standing). Additional 466 patients with type 2 diabetes mellitus were included in this study. Their clinical characteristics and long-term outcomes were analysed.

RESULTS

In comparison with patients with type 2 diabetes mellitus alone, PDAC patients with new-onset diabetes mellitus had an older onset age of diabetes mellitus and lower body mass index (BMI). Among PDAC cases, patients with new-onset diabetes mellitus were associated with neural invasion, poor tumour differentiation and shorter post-surgical survival. However, more than half of these patients became euglycemic after surgical resection of tumours.

CONCLUSIONS

PDAC patients developed new-onset diabetes mellitus at an older age, and they had shorter post-surgical survival. The underlying mechanisms by which comorbid diabetes mellitus affect the clinical profiles and outcomes of PDAC patients deserve further researches.

New-onset diabetes in pancreatic cancer: a study in the primary care setting

BACKGROUND

Onset of diabetes mellitus (DM) is often first noted by primary care physicians. New-onset DM (duration <36 months before PaC diagnosis) can be a harbinger of pancreatic cancer (PaC). However, its clinical significance remains unclear.

METHODS

To determine the prevalence, onset, and delay in diagnosis of DM in PaC patients in the primary care setting, we retrospectively reviewed the records of consecutive patients followed in Mayo Clinic's primary care clinics (at least one visit in the preceding 2 years) from 1995 to 2009 who were eventually diagnosed with PaC. Onset of DM was the first date the fasting blood glucose was ≥126 mg/dl.

RESULTS

Of the 111 PaC patients (59 male, median age 74 years), 52 (47%) had DM of whom 30 (58%) had new-onset DM. Among the 30 with new-onset DM, 24 (80%) were asymptomatic (no cancer-specific symptoms), at DM onset. In these 24 patients, median duration of DM prior to PaC diagnosis was 6.5 (0.5-35) months, and median delay between onset and physician diagnosis of DM was 2.5 (0.25-14) months, which decreased from 8.8 (3.5-14) months in patients with DM onset between 1995 and 1999 to 0 (0-2) months, in patients with DM onset between 2004 and 2009. However, the proportion of patients with undiagnosed DM (~33%) remained unchanged.

CONCLUSIONS

Diabetes is very common (~50%) in PaC. In over a fifth of PaC, the onset of DM occurs when the cancer is asymptomatic, providing a potential window-of-opportunity to diagnose early PaC. However, nearly a third of new-onset DM in PaC remains undiagnosed.

Diabetes mellitus, glycated haemoglobin and C-peptide levels in relation to pancreatic cancer risk: a study within the European Prospective Investigation into Cancer and Nutrition (EPIC) cohort

AIMS/HYPOTHESIS

There has been long-standing debate about whether diabetes is a causal risk factor for pancreatic cancer or a consequence of tumour development. Prospective epidemiological studies have shown variable relationships between pancreatic cancer risk and blood markers of glucose and insulin metabolism, overall and as a function of lag times between marker measurements (blood donation) and date of tumour diagnosis.

METHODS

Pre-diagnostic levels of HbA(1c) and C-peptide were measured for 466 participants with pancreatic cancer and 466 individually matched controls within the European Prospective Investigation into Cancer and Nutrition. Conditional logistic regression models were used to estimate ORs for pancreatic cancer.

RESULTS

Pancreatic cancer risk gradually increased with increasing pre-diagnostic HbA(1c) levels up to an OR of 2.42 (95% CI 1.33, 4.39 highest [≥ 6.5%, 48 mmol/mol] vs lowest [≤ 5.4%, 36 mmol/mol] category), even for individuals with HbA(1c) levels within the non-diabetic range. C-peptide levels showed no significant relationship with pancreatic cancer risk, irrespective of fasting status. Analyses showed no clear trends towards increasing hyperglycaemia (as marked by HbA(1c) levels) or reduced pancreatic beta cell responsiveness (as marked by C-peptide levels) with decreasing time intervals from blood donation to cancer diagnosis.

CONCLUSIONS/INTERPRETATION

Our data on HbA(1c) show that individuals who develop exocrine pancreatic cancer tend to have moderate increases in HbA(1c) levels, relatively independently of obesity and insulin resistance-the classic and major risk factors for type 2 diabetes. While there is no strong difference by lag time, more data are needed on this in order to reach a firm conclusion.

High glucose promotes pancreatic cancer cell proliferation via the induction of EGF expression and transactivation of EGFR

Multiple lines of evidence suggest that a large portion of pancreatic cancer patients suffer from either hyperglycemia or diabetes, both of which are characterized by high blood glucose level. However, the underlying biological mechanism of this phenomenon is largely unknown. In the present study, we demonstrated that the proliferative ability of two human pancreatic cancer cell lines, BxPC-3 and Panc-1, was upregulated by high glucose in a concentration-dependent manner. Furthermore, the promoting effect of high glucose levels on EGF transcription and secretion but not its receptors in these PC cell lines was detected by using an EGF-neutralizing antibody and RT-PCR. In addition, the EGFR transactivation is induced by high glucose levels in concentration- and time-dependent manners in PC cells in the presence of the EGF-neutralizing antibody. These results suggest that high glucose promotes pancreatic cancer cell proliferation via the induction of EGF expression and transactivation of EGFR. Our findings may provide new insight on the links between high glucose level and PC in terms of the molecular mechanism and reveal a novel therapeutic strategy for PC patients who simultaneously suffer from either diabetes or hyperglycemia.