Factor In Pancreatic Ductal Adenocarcinoma Research Articles

Pancreatic Tumor Microenvironment Modulation by EphB4-ephrinB2 Inhibition and Radiation Combination.

A driving factor in pancreatic ductal adenocarcinoma (PDAC) treatment resistance is the tumor microenvironment, which is highly immunosuppressive. One potent immunologic adjuvant is radiotherapy. Radiation, however, has also been shown to induce immunosuppressive factors, which can contribute to tumor progression and formation of fibrotic tumor stroma. To capitalize on the immunogenic effects of radiation and obtain a durable tumor response, radiation must be rationally combined with targeted therapies to mitigate the influx of immunosuppressive cells and fibrosis. One such target is ephrinB2, which is overexpressed in PDAC and correlates negatively with prognosis.Experimental Design: On the basis of previous studies of ephrinB2 ligand-EphB4 receptor signaling, we hypothesized that inhibition of ephrinB2-EphB4 combined with radiation can regulate the microenvironment response postradiation, leading to increased tumor control in PDAC. This hypothesis was explored using both cell lines and in vivo human and mouse tumor models. Our data show this treatment regimen significantly reduces regulatory T-cell, macrophage, and neutrophil infiltration and stromal fibrosis, enhances effector T-cell activation, and decreases tumor growth. Furthermore, our data show that depletion of regulatory T cells in combination with radiation reduces tumor growth and fibrosis. These are the first findings to suggest that in PDAC, ephrinB2-EphB4 interaction has a profibrotic, protumorigenic role, presenting a novel and promising therapeutic target.

Concentrations of trace elements and KRAS mutations in pancreatic ductal adenocarcinoma.

Trace elements are a possible risk factor for pancreatic ductal adenocarcinoma (PDAC). However, their role in the occurrence and persistence of KRAS mutations remains unstudied. There appear to be no studies analyzing biomarkers of trace elements and KRAS mutations in any human cancer. We aimed to determine whether patients with KRAS mutated and nonmutated tumors exhibit differences in concentrations of trace elements. Incident cases of PDAC were prospectively identified in five hospitals in Spain. KRAS mutational status was determined through polymerase chain reaction from tumor tissue. Concentrations of 12 trace elements were determined in toenail samples by inductively coupled plasma mass spectrometry. Concentrations of trace elements were compared in 78 PDAC cases and 416 hospital-based controls (case-control analyses), and between 17 KRAS wild-type tumors and 61 KRAS mutated tumors (case-case analyses). Higher levels of iron, arsenic, and vanadium were associated with a statistically nonsignificant increased risk of a KRAS wild-type PDAC (OR for higher tertile of arsenic = 3.37, 95% CI 0.98-11.57). Lower levels of nickel and manganese were associated with a statistically significant higher risk of a KRAS mutated PDAC (OR for manganese = 0.34, 95% CI 0.14-0.80). Higher levels of selenium appeared protective for both mutated and KRAS wild-type PDAC. Higher levels of cadmium and lead were clear risk factors for both KRAS mutated and wild-type cases. This is the first study analyzing biomarkers of trace elements and KRAS mutations in any human cancer. Concentrations of trace elements differed markedly between PDAC cases with and without mutations in codon 12 of the KRAS oncogene, thus suggesting a role for trace elements in pancreatic and perhaps other cancers with such mutations. Environ. Mol. Mutagen., 60:693-703, 2019. © 2019 Wiley Periodicals, Inc.

The Significance of Ascites in Patients With Pancreatic Ductal Adenocarcinoma: A Case-Control Study.

Limited data exist on the impact of ascites in pancreatic ductal adenocarcinoma (PDAC). We evaluated the survival outcomes of patients with PDAC and ascites. Retrospective, single-institution, case-control study including patients with newly diagnosed PDAC from 2007 to 2016. One hundred fifty-four patients with ascites at diagnosis (case group) and 154 controls were matched on age, sex, stage, Eastern Cooperative Oncology Group performance, surgical treatment, lymph node, and margin status. Ascites was defined as computed tomography-detected fluid in the pelvic/peritoneal cavity. Overall survival was compared between groups via Cox proportional hazards models with a gamma frailty term to account for the correlation between matched pairs on entire cohort and by disease stages for subgroup analysis. The 154 matched cases included 24 resectable, 19 borderline resectable, 51 locally advanced, and 60 metastatic disease. Patients with ascites had higher risk of death compared with those without (conditional hazard ratio, 1.58; 95% confidence interval, 1.23-2.03; P < 0.001). Stratified analysis showed a significant association between ascites and poor prognosis in patients with localized disease (conditional hazard ratio, 1.62; 95% confidence interval, 1.18-2.24; P = 0.003). Radiographic ascites is a poor prognostic factor in PDAC. Our findings may aid physicians in considering systemic therapy prior to attempting local treatments.

Impact of calcifications on diagnostic yield of endoscopic ultrasound-guided fine-needle aspiration for pancreatic ductal adenocarcinoma.

Chronic calcific pancreatitis (CCP) is a major risk factor for pancreatic ductal adenocarcinoma (PDAC) and is common in southern India. Endoscopic ultrasound fine-needle aspiration (EUS-FNA) is useful for tissue acquisition in patients with solid pancreatic lesions. Multiple factors may affect the diagnostic yield ofFNA samples. The present study was performed to assess the impact of pancreatic calcifications on the diagnostic yield of EUS-FNA in PDAC. All patients with confirmed PDAC from January 2013 to December 2017 were included. CCP was diagnosed based on typicalimaging characteristics with or without evidence of pancreatic insufficiency along with surgical histopathology reports showing features of chronic pancreatitis. The diagnostic yield and adequacy of cellularity were assessed by a pathologist who was blinded and were compared between the two groups: group 1: PDAC patients with no evidence of CCP and, group 2: PDAC patients with CCP. A total of 122 patients were included in the study. The diagnostic yield was lower in patients in group 2 (n= 42, 25 [59.52%]) as compared to those in group 1 (n= 80, 63 [78.75%]) (p-value = 0.01). On multivariate analysis, only the presence of calcifications was found to have an independent association with diagnostic yield (odds ratio 3.83 [95% confidence interval 1.22-11.9]). CCP had a significant impact on the diagnostic yield of EUS-FNA for pancreatic adenocarcinoma. Novel techniques and newer technology that may mitigate the negative effect of calcification on diagnostic yield of EUS-FNA in patients withCCP.

Tumor Size and Number of Positive Lymph Nodes are Significant Prognostic Factors of Pancreatic Ductal Adenocarcinoma

Tumor Size and Number of Positive Lymph Nodes are Significant Prognostic Factors of Pancreatic Ductal Adenocarcinoma

Dissected peripancreatic tissue margin is a critical prognostic factor and is associated with a K-ras gene mutation in pancreatic ductal adenocarcinoma.

We previously reported that the dissected pancreatic tissue margin (DPM) and the preoperative serum level of carbohydrate antigen 19-9 (preCA19-9) were independent prognostic factors in pancreatic ductal adenocarcinoma (PDAC). In the current study, the prognostic relevance of these factors, including their molecular associations, were validated. A total of 161 patients with PDAC underwent a pancreatectomy between 1986 and 2013, and a multivariate Cox proportional hazards model and a propensity score-based model validated the prognostic importance of DPM. The prognostic factors were compared with the mutation profiles of the K-ras and TP53 genes. Univariate prognostic analysis of disease-specific survival (DSS) demonstrated that DPM (P<0.0001), preCA19-9 (P<0.0001) and Union for International Cancer Control (UICC) stage (P<0.0001), were all significantly associated with poor outcome in PDAC. A multivariate Cox proportional hazards model confirmed that preCA19-9 (P=0.0002) and DPM (P=0.0002) remained as prognostic factors independent of UICC stage (P=0.0015). The combination of preCA19-9 and DPM to predict prognosis could accurately identify the long-term survivors of PDAC (70% 5-year DSS), and a multivariate logistic regression model identified that DPM was the most effective predictor of mortality. The prognostic relevance of DPM was also confirmed (P=0.0008) through propensity score-based background adjustment of patient bias. K-ras gene mutation was significantly associated with DPM (P=0.0002), and DPM-positive patients demonstrated recurrence of distant metastasis in 67% of cases. Therefore, DPM is a critical prognostic indicator in PDAC. In combination with preCA19-9, DPM may be useful to identify long-term survivors of PDAC. Furthermore, to the best of our knowledge, the current study was the first to discover that DPM can represent a poor prognosis based putatively on its association with the K-ras gene mutation.

Ductal obstruction promotes formation of preneoplastic lesions from the pancreatic ductal compartment.

Pancreatitis is a significant risk factor for pancreatic ductal adenocarcinoma (PDAC). Previous studies in mice have demonstrated that pancreatitis contributes to oncogenic Kras-driven carcinogenesis, probably initiated in acinar cells; however, oncogenic Kras alone or in combination with caerulein-induced pancreatitis is not sufficient in initiating PDAC from the ductal compartment. We thus introduced ductal obstruction - which induces a more severe form of pancreatitis - by pancreatic ductal ligation in mice harbouring oncogenic Kras. This induced a particular phenotype with highly proliferative nonmucinous cells with nuclear atypia. Around these lesions, there was a significant proliferation of activated fibroblasts and infiltration of immune cells, corroborating the pathological features of preneoplastic lesions. Lineage-tracing experiments revealed that these preneoplastic cells derived from two distinctive cellular sources: acinar and ductal cells. Phenotypic characterisation revealed that the duct-derived preneoplastic lesions show a high proliferative potential with persistent activation of tumour-promoting inflammatory pathways while the acinar-derived ones were less proliferative with persistent p53 activation. Furthermore, the duct-derived preneoplastic cells have a particularly high nuclear-to-cytoplasmic ratio. These data demonstrate that ductal obstruction promotes preneoplastic lesion formation from the pancreatic ductal compartment.

Tobacco Carcinogen-Induced Production of GM-CSF Activates CREB to Promote Pancreatic Cancer.

Although smoking is a significant risk factor for pancreatic ductal adenocarcinoma (PDAC), the molecular mechanisms underlying PDAC development and progression in smokers are still unclear. Here, we show the role of cyclic AMP response element-binding protein (CREB) in the pathogenesis of smoking-induced PDAC. Smokers had significantly higher levels of activated CREB when compared with nonsmokers. Cell lines derived from normal pancreas and pancreatic intraepithelial neoplasm (PanIN) exhibited low baseline pCREB levels compared with PDAC cell lines. Furthermore, elevated CREB expression correlated with reduced survival in patients with PDAC. Depletion of CREB significantly reduced tumor burden after tobacco-specific nitrosamine 4-(methyl nitrosamino)-1-(3-pyridyl)-1-butanone (NNK) treatment, suggesting a CREB-dependent contribution to PDAC growth and progression in smokers. Conversely, NNK accelerated PanIN lesion and PDAC formation via GM-CSF-mediated activation of CREB in a PDAC mouse model. CREB inhibition (CREBi) in mice more effectively reduced primary tumor burden compared with control or GM-CSF blockade alone following NNK exposure. GM-CSF played a role in the recruitment of tumor-associated macrophages (TAM) and regulatory T cell (Treg) expansion and promotion, whereas CREBi significantly reduced TAM and Treg populations in NNK-exposed mice. Overall, these results suggest that NNK exposure leads to activation of CREB through GM-CSF, promoting inflammatory and Akt pathways. Direct inhibition of CREB, but not GM-CSF, effectively abrogates these effects and inhibits tumor progression, offering a viable therapeutic strategy for patients with PDAC.Significance: These findings identify GM-CSF-induced CREB as a driver of pancreatic cancer in smokers and demonstrate the therapeutic potential of targeting CREB to reduce PDAC tumor growth.Graphical Abstract: http://cancerres.aacrjournals.org/content/canres/78/21/6146/F1.large.jpg Cancer Res; 78(21); 6146-58. ©2018 AACR.

Tumor-Infiltrating NETs Predict Postsurgical Survival in Patients with Pancreatic Ductal Adenocarcinoma.

Tumor-infiltrating neutrophils (TINs) indicate poor prognosis for patients with pancreatic ductal adenocarcinoma (PDAC). Activated neutrophils can generate neutrophil extracellular traps (NETs). Little is known about the presence and prognostic significance of tumor-infiltrating NETs in PDAC. This study enrolled 317 patients, in two independent sets (training and validation), who underwent curative pancreatectomy for PDAC in Shanghai Cancer Center. TINs and NETs were identified by immunohistochemical staining for CD15 and citrullinated histone H3, respectively. The relationship between clinicopathological features and outcomes was analyzed. Accuracy of prognostic prediction models was evaluated using concordance index (C-index) and Akaike information criterion (AIC). NETs were associated with OS (both, P < 0.001) and RFS (both, P < 0.001) in the training and validation sets. Tumor-infiltrating NETs predicted poor postsurgical survival of patients with PDAC. Moreover, multivariate analysis identified NETs and AJCC TNM stage as two independent prognostic factors for OS and RFS. Combination of NETs with the 8th edition TNM staging system (C-index, 0.6994 and 0.6669, respectively; AIC, 1067 and 1126, respectively) generated a novel model that improved the predictive accuracy for survival in both sets (C-index, 0.7254 and 0.7117, respectively; AIC, 1047 and 1102, respectively). The model combining presence of NETs with the 7th edition AJCC TNM staging system also had improved predictive accuracy. NETs were an independent prognostic factor in PDAC and incorporation of NETs along with the standard TNM stating system refined risk-stratification and predicted survival in PDAC with improved accuracy.

Prognostic Value of Preoperative Nutritional and Immunological Factors in Patients with Pancreatic Ductal Adenocarcinoma.

Preoperative nutritional and immunological patient factors have been found to be associated with prognostic outcomes of malignant tumors; however, the clinical significance of these factors in pancreatic ductal adenocarcinoma (PDAC) remains controversial. The aim of this study was to evaluate the prognostic value of nutritional and immunological factors in predicting survival of patients with PDAC. Retrospective studies of 329 patients who underwent surgical resection for PDAC and 95 patients who underwent palliative surgery were separately conducted to investigate the prognostic impact of tumor-related factors and patient-related factors, including Glasgow Prognostic Score (GPS), modified GPS, Prognostic Nutritional Index (PNI), neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio, and lymphocyte/monocyte ratio. In multivariate analysis for patients with surgical resection for PDAC, PNI was an independent factor for overall survival (OS) and disease-free survival. The median OS of patients with PNI ≤ 45 was significantly shorter than that of patients with PNI > 45 (17.5 and 36.2months, respectively; p < 0.001). In multivariate analysis for patients undergoing palliative surgery for PDAC, only NLR was an independent prognosis factor. The median OS of patients with NLR > 5 was significantly shorter than that of patients with NLR ≤ 5 (2.7 and 8.9months, respectively; p < 0.001). PNI in patients with surgical resection and NLR in patients with palliative surgery for PDAC may be useful prognostic factors.

Norepinephrine enhances cell viability and invasion, and inhibits apoptosis of pancreatic cancer cells in a Notch‑1‑dependent manner.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive types of cancer, which is associated with a poor prognosis due to complexities in prevention, early diagnosis and effective treatment. The lack of understanding regarding its induction and specific pro‑cancer mechanisms may contribute to its poor prognosis. The Notch‑1 pathway is widely considered to be a critical tumor‑promoting factor in PDAC. Previous studies have indicated that chronic psychological stress may promote the development of PDAC partially via the main downstream stress hormone, norepinephrine (NE); however, to the best of our knowledge, the role of the Notch‑1 pathway in this process has not been studied. Therefore, the present study aimed to explore this process. The expression levels of Notch‑1 pathway‑associated molecules were measured in response to NE using reverse transcription‑quantitative polymerase chain reaction and western blotting. Alongside NE treatment, two Notch‑1 pathway blockers, Notch‑1‑specific small interfering (si)RNA and DAPT (an inhibitor of the Notch‑1 pathway), were used to explore the relationship between NE and the Notch‑1 pathway in the development of pancreatic cell malignant biological behaviors, including cell viability, apoptosis and cell invasion. The results demonstrated that treatment with NE enhanced cell viability and invasion, and inhibited apoptosis of PDAC cells; however, these effects were suppressed following treatment with Notch‑1‑specific siRNA and DAPT. In conclusion, NE may enhance the malignant biological behaviors of PDAC via activating the Notch‑1 pathway.

Nodal status in pancreatic ductal adenocarcimoa: a survival analysis

OS after surgery for pancreatic ductal adenocarcinoma (PDAC) is poor. While some studies suggest that N1 is an important prognostic factor after R0 resection, other data imply that nodal disease per se is not associated with survival outcome. The aim of this study was to identify prognostic variables in PDAC and to investigate the value of lymph node (LN) involvement, LN ratio (LNR) and log odds of positive LN (LODDS). Clinicopathological data from 284 patients who received resection for PDAC were analysed. LNR (ratio of positive LN to examined LN) and LODDS (log(positive LN+0.5)/(total LN+0.5)) were calculated. Of the 284 patients, 252 underwent surgery for pancreatic head carcinoma. 223 patients showed N1, while 36 presented with M1. 102 patients displayed a LNR >0.2. 120 patients showed -0.5≤LODDS<0. In our cohort, N1 status was not associated with poor prognosis (p=0.158). LNR >0.2 and LODDS subgroup were correlated with poor survival in univariate analysis (p=0.001 and p=0.012). In multivariate analysis, only LNR >0.2 and M1 status correlated with poor survival. Furthermore a subgroup analysis was performed for 163 patients who received R0 resection for N1 PDAC without M1. In both MV and UV analysis, LNR >0.2 and LODDS subgroup were correlated with poor survival. While N1 per se is of no prognostic value in PDAC, interestingly, LNR and LODDS are an independent prognostic factor in PDAC. Therefore, should be included in pathologic reporting after PDAC resection and taken into consideration for prognosis assessment of PDAC patients.

Evaluating the diagnostic and prognostic value of long non-coding RNA SNHG15 in pancreatic ductal adenocarcinoma.

Long non-coding RNA SNHG15 (SNHG15) has been reported to play very important roles in the malignancy behaviors of various tumors, including pancreatic ductal adenocarcinoma (PDAC). However, its clinical significance in PDAC remains largely unclear. The aim of this study was to investigate whether the aberrant expression of SNHG15 can be used as potential prognostic and diagnostic markers of human PDAC. TaqMan Real Time-PCR was performed to investigate the expression of SNHG15 in PDAC tissues and serum samples. Receiver operator characteristic (ROC) analysis was applied to obtain the diagnostic utility of SNHG15. Association between SNHG15 levels and clinicopathological factors was analyzed. Kaplan-Meier curves and multivariate Cox proportional models were used to study the impact on clinical outcome. SNHG15 levels were significantly up-regulated in both sera and tumors tissues from PDAC patients. ROC curve analysis revealed that SNHG15 may be a potential biomarker for differentiating PDAC tissues from normal pancreatic tissues, and the plasma levels of SNHG15 may be a potential biomarker for differentiating PDAC patients from healthy controls. Clinicopathologic analysis revealed that high SNHG15 expression was associated with tumor differentiation (p = 0.000), lymph node metastasis (p = 0.001) and tumor stage (p = 0.005). Furthermore, patients with high SNHG15 expression had a shorter overall survival compared with the low SNHG15 expression group (p = 0.003). Also, Cox multivariate analyses confirmed that SNHG15 expression was an independent prognostic factor in PDAC (p < 0.004). Our study firstly indicated the potential value of SNHG15 as an important biomarker for the diagnosis and prognosis prediction of PDAC.

Expression of phosphorylated estrogen receptor beta is an independent negative prognostic factor for pancreatic ductal adenocarcinoma.

The role of estrogen receptor beta (ER-β) expression in pancreatic ductal adenocarcinoma (PDAC) is largely unknown. Ligand-independent phosphorylation and activation of ER-β may play a relevant role in the IL-6/STAT3 signaling pathway and, as a result, in tumor progression. Here, we examined the effect of ER-β, phosphorylated ER-β (pER-β), STAT3, phosphorylated STAT3 (pSTAT3) and IL-6 expression on the overall and recurrence-free survival in a cohort of patients with resected PDAC. We identified 175 patients who underwent pancreatic resection for PDAC. Tissue microarrays were constructed from the archival tumor specimens. These were stained with specific antibodies for the above molecules. The expression of the markers was then correlated with clinicopathological parameters and survival analysis was performed. High nuclear expression of ER-β was found in 61.7% and pER-β in 80.6% of the tumors. STAT3 was expressed in 54.3% of the tumor samples, pSTAT3 in 68% and IL-6 in 76.6%. The median overall survival for patients with low pER-β expression was 29 months, whereas for patients with high pER-β expression was 15.1 months (p = 0.016). Multivariate analysis revealed that pER-β expression was an independent factor correlating with shorter overall survival (hazard ratio 1.9; p = 0.013) and disease-free survival (hazard ratio 1.9; p = 0.029). Expression of pER-β constitutes an independent prognostic marker for PDAC and is correlated with poor prognosis. These data may help in identifying novel drug targets in PDAC and patients who could benefit from additional therapeutic regimens, including selective estrogen receptor modulators.

Abstract SY29-01: Role of nitrogen metabolism in obesity-associated pancreatic cancer

Abstract Obesity is an established risk factor for pancreatic ductal adenocarcinoma (PDAC). Despite recent identification of metabolic alterations in this lethal malignancy, the metabolic dependencies of obesity-associated PDAC remain unknown. Here we show that obesity-driven PDAC exhibits accelerated growth and a striking transcriptional enrichment for pathways regulating nitrogen metabolism. We find that the mitochondrial form of arginase (ARG2), which hydrolyzes arginine into ornithine and urea, is induced upon obesity, and silencing or loss of ARG2 markedly suppresses PDAC. In vivo infusion of 15N-glutamine in obese mouse models of PDAC demonstrates enhanced nitrogen flux into the urea cycle, and infusion of 15N-arginine shows that Arg2 loss causes significant ammonia accumulation that results from the shunting of arginine catabolism into alternative nitrogen repositories. Furthermore, analysis of PDAC patient tumors indicates that ARG2 levels correlate with body mass index (BMI). The specific dependency of PDAC on ARG2 rather than the principal hepatic ureagenic enzyme ARG1 opens a therapeutic window for obesity-associated pancreatic cancer. Citation Format: Nada Y. Kalaany. Role of nitrogen metabolism in obesity-associated pancreatic cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr SY29-01.

MicroRNA-29b-2-5p inhibits cell proliferation by directly targeting Cbl-b in pancreatic ductal adenocarcinoma

BackgroundMicroRNAs can be used in the prognosis of malignancies; however, their regulatory mechanisms are unknown, especially in pancreatic ductal adenocarcinoma (PDAC).MethodsIn 120 PDAC specimens, miRNA levels were assessed by quantitative real time polymerase chain reaction (qRT-PCR). Then, the role of miR-29b-2-5p in cell proliferation was evaluated both in vitro (Trypan blue staining and cell cycle analysis in the two PDAC cell lines SW1990 and Capan-2) and in vivo using a xenograft mouse model. Next, bioinformatics methods, a luciferase reporter assay, Western blot, and immunohistochemistry (IHC) were applied to assess the biological effects of Cbl-b inhibition by miR-29b-2-5p. Moreover, the relationship between Cbl-b and p53 was evaluated by immunoprecipitation (IP), Western blot, and immunofluorescence.ResultsFrom the 120 PDAC patients who underwent surgical resection, ten patients with longest survival and ten with shortest survival were selected. We found that high miR-29b-2-5p expression was associated with good prognosis (p = 0.02). The validation cohort confirmed miR-29b-2-5p as an independent prognostic factor in PDAC (n = 100, 95% CI = 0.305–0.756, p = 0.002). Furthermore, miR-29b-2-5p inhibited cell proliferation, induced cell cycle arrest, and promoted apoptosis both in vivo and in vitro. Interestingly, miR-29b-2-5p directly bound the Cbl-b gene, down-regulating its expression and reducing Cbl-b-mediated degradation of p53. Meanwhile, miR-29b-2-5p expression was negatively correlated with Cbl-b in PDAC tissues (r = − 0.33, p = 0.001).ConclusionsTaken together, these findings indicated that miR-29b-2-5p improves prognosis in PDAC by targeting Cbl-b to promote p53 expression, and would constitute an important prognostic factor in PDAC.

Tumour budding in pancreatic cancer revisited: validation of the ITBCC scoring system.

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with rising incidence. Biomarkers that would help the prognostic stratification of patients are needed urgently. Although tumour budding (BD) is a strong and independent prognostic factor in PDAC it is not included in histopathology reports, due partly to the lack of a standardised scoring system. The aim of the present work is to assess the reliability and reproducibility of the BD scoring system proposed recently by the International Tumour Budding Consensus Conference (ITBCC) 2016 in a well-characterised PDAC cohort (n=120) with complete clinicopathological and follow-up information. BD was scored independently by two pathologists on haematoxylin and eosin-stained PDAC sections by assessing the densest budding area at ×20 magnification (one hot-spot, 0.785mm2 ), regardless of intra- or peritumoural localisation, and assigned to four categories: BD0: no buds; BD1: one to four buds; BD2: five to nine buds; and BD3: ≥10 buds. Findings were correlated to patient and tumour characteristics and interobserver agreement was assessed. The weighted kappa value for BD category was 0.62 (0.5-0.73), indicating strong agreement. Increasing BD category (BD3 versus BD0-2) correlated with higher grade (P=0.002) and shorter overall [OS, P<0.0001, hazard ratio (HR)=3.234, 95% confidence interval (CI)=1.95-5.37] and disease-free survival (DFS, P=0.0135, HR=1.974, 95% CI=1.15-3.39). BD (BD3 versus BD0-2) was an independent prognostic factor for OS and DFS, after adjusting for tumour-node-metastasis (TNM) stage by using both the 8th American Joint Committee on Cancer (AJCC) edition (OS: P=0.0031, HR= 2.298, 95% CI=1.32-0.99; DFS: P=0.0458, HR=1.713, 95% CI=1.01-2.91) and the 7th AJCC edition (OS: P<0.0001, HR=2.795,95% CI=1.71-4.57 and DFS: P=0.00786, HR=1.643, 95% CI=0.95-2.86). ITBCC scoring is a simple, reliable and reproducible method to evaluate BD in PDAC and facilitates its documentation in histopathology reports, allowing the prognostic stratification of PDAC patients.

SPARC Expression as a Prognostic Marker in Pancreatic Ductal Adenocarcinoma

Background: The aim is to investigate whether secreted protein acidic and rich in cysteine (SPARC) expression could be considered as an independent prognostic factor in pancreatic ductal adenocarcinoma (PDAC). Methods: The expression of SPARC in the tumor species was detected by immunochemistry and the effect of SPARC on the prognosis was analyzed by Kaplan-Meier and Cox proportional hazard models. Results: Positive SPARC expressions recognized in tumor and stroma were 31.33% and 64.66% respectively. The expression of SPARC in stroma was closely correlated with differentiation, vascular invasion and was an indicator for predicting poor outcome after surgery in Kaplan-Meier analysis. Univariate analysis and multivariate analysis showed the following factors to be significant: perineural invasion (HR = 2.098, 95% CI: 1.144 - 3.847) and stroma positive expression of SPARC (HR = 2.120, 95% CI: 1.307 - 3.440). Conclusions: High expression of SPARC in stroma was a promising pathological marker to predict the poor outcome in patients with pancreatic ductal adenocarcinoma.

Association between the Risk Factors for Pancreatic Ductal Adenocarcinoma and Those for Malignant Intraductal Papillary Mucinous Neoplasm

Background and Aims: Risk factors for pancreatic ductal adenocarcinoma (PDAC) include diabetes mellitus, chronic pancreatitis, obesity, a family history of pancreatic cancer, and a history of smoking or alcohol consumption. The aim of this study was to evaluate the association between risk factors for PDAC and malignant intraductal papillary mucinous neoplasm (IPMN). Methods: The study included 134 consecutive patients with IPMN who underwent surgical resection at Kindai University Hospital between April 2009 and March 2015. Data on the presence or absence of mural nodules (MNs) and risk factors for PDAC were evaluated. Multivariable logistic regression analysis was performed with malignant IPMN as the outcome variable and MNs and risk factors for PDAC as explanatory variables. Results: The odds ratio of malignant IPMN to MNs was 3.88 (95% confidence interval [CI] 1.53-9.84; p = 0.004), whereas that of malignant IPMN to smoking history was 1.66 (95% CI 0.74-3.71; p = 0.22). When the presence of MNs was considered as a predictive factor for malignancy, the sensitivity and specificity were 88.5 and 32.1%, respectively, whereas when the presence of both smoking history and MNs was considered, the specificity improved to 73.2%, with a decrease in sensitivity to 42.3%. Conclusions: The presence of both a smoking history and MNs was a valuable predictive factor for malignant IPMN with high specificity. A smoking history should be considered before surgical resection in addition to the presence of MNs.

Relationship between LAT1 expression and resistance to chemotherapy in pancreatic ductal adenocarcinoma.

L-type amino acid transporter 1 (LAT1) is linked to tumor cell proliferation, angiogenesis, and survival in various human cancers. Although the expression of LAT1 was identified as a significant prognostic predictor after surgery in patients with pancreatic ductal adenocarcinoma (PDAC), little is known about the clinical significance of LAT1 as a chemotherapeutic resistance factor in PDAC. A total of 110 patients with surgically resected PDAC were retrospectively reviewed as the training set. Immunohistochemical staining of resected tumor specimens was assessed using anti-LAT1 antibodies. In vitro analysis of chemotherapy resistance and LAT1 function using PDAC cell lines was also performed. The rate of high expression of LAT1 was 64.1% (71/110). The high expression of LAT1 protein was significantly associated with tumor differentiation, tumor depth (T factor), lymph node metastasis, venous invasion, recurrence, and clinical response. By multivariate analysis, LAT1 was validated as an independent prognostic factor for predicting worse survival after surgery. We analyzed the TCGA data set and obtained similar results that the survival rates of SLC7A5 high expression group were poorer than that of low expression group. LAT1 could successfully predict the outcome of patients who received adjuvant chemotherapy after surgery (n = 88) and systemic chemotherapy after recurrence (n = 56). All patients with high LAT1 expression were non-responders, whereas approximately 30% of the patients with low LAT1 expression responders (p = 0.0002). By analyzing the TCGA online database, it was found that LAT1 closely correlated with hypoxia-induced genes, such as PTGES, PYGL, and KPNA2. LAT1 as an independent prognostic marker is a potential molecular targeting gene to reduce chemoresistance and tumor growth in patients with PDAC, supported by our in vitro study.