Exploiting inflammation for therapeutic gain in pancreatic cancer

Advancements in Pancreatic Cancer Detection: Integrating Biomarkers, Imaging Technologies, and Machine Learning for Early Diagnosis

Artificial intelligence (AI) has come to play a pivotal role in revolutionizing medical practices, particularly in the field of pancreatic cancer detection and management. As a leading cause of cancer-related deaths, pancreatic cancer warrants innovative approaches due to its typically advanced stage at diagnosis and dismal survival rates. Present detection methods, constrained by limitations in accuracy and efficiency, underscore the necessity for novel solutions. AI-driven methodologies present promising avenues for enhancing early detection and prognosis forecasting. Through the analysis of imaging data, biomarker profiles, and clinical information, AI algorithms excel in discerning subtle abnormalities indicative of pancreatic cancer with remarkable precision. Moreover, machine learning (ML) algorithms facilitate the amalgamation of diverse data sources to optimize patient care. However, despite its huge potential, the implementation of AI in pancreatic cancer detection faces various challenges. Issues such as the scarcity of comprehensive datasets, biases in algorithm development, and concerns regarding data privacy and security necessitate thorough scrutiny. While AI offers immense promise in transforming pancreatic cancer detection and management, ongoing research and collaborative efforts are indispensable in overcoming technical hurdles and ethical dilemmas. This review delves into the evolution of AI, its application in pancreatic cancer detection, and the challenges and ethical considerations inherent in its integration.

Pancreatic Ductal Adenocarcinoma Cells Regulate NLRP3 Activation to Generate a Tolerogenic Microenvironment

Defining feature of pancreatic ductal adenocarcinoma (PDAC) that participates in the high mortality rate and drug resistance is the immune-tolerant microenvironment which enables tumors to progress unabated by adaptive immunity. In this study, we report that PDAC cells release CSF-1 to induce nucleotide-binding domain, leucine-rich containing family, pyrin domain-containing-3 (NLRP3) activation in myeloid cells. Increased NLRP3 expression was found in the pancreas of patients with PDAC when compared with normal pancreas which correlated with the formation of the NLRP3 inflammasome. Using human primary cells and an orthotopic PDAC mouse model, we show that NLRP3 activation is responsible for the maturation and release of the inflammatory cytokine IL1β which selectively drives Th2-type inflammation via COX2/PGE2 induction. As a result of this inflammation, primary tumors were characterized by reduced cytotoxic CD8+ T-cell activation and increased tumor expansion. Genetic deletion and pharmacologic inhibition of NLRP3 enabled the development of Th1 immunity, increased intratumoral levels of IL2, CD8+ T cell–mediated tumor suppression, and ultimately limited tumor growth. In addition, we observed that NLRP3 inhibition in combination with gemcitabine significantly increased the efficacy of the chemotherapy. In conclusion, this study provides a mechanism by which tumor-mediated NLRP3 activation exploits a distinct adaptive immunity response that facilitates tumor escape and progression. Considering the ability to block NLRP3 activity with safe and small orally active molecules, this protein represents a new promising target to improve the limited therapeutic options in PDAC.

SIGNIFICANT

This study provides novel molecular insights on how PDAC cells exploit NLRP3 activation to suppress CD8 T-cell activation. From a translational perspective, we demonstrate that the combination of gemcitabine with the orally active NLRP3 inhibitor OLT1177 increases the efficacy of monotherapy.

Tumor heterogeneity: An oncogenic driver of PDAC progression and therapy resistance under stress conditions

Pancreatic ductal adenocarcinoma (PDAC) is a clinically challenging disease usually diagnosed at advanced or metastasized stage. By this year end, there are an expected increase in 62,210 new cases and 49,830 deaths in the United States, with 90% corresponding to PDAC subtype alone. Despite advances in cancer therapy, one of the major challenges combating PDAC remains tumor heterogeneity between PDAC patients and within the primary and metastatic lesions of the same patient. This review describes the PDAC subtypes based on the genomic, transcriptional, epigenetic, and metabolic signatures observed among patients and within individual tumors. Recent studies in tumor biology suggest PDAC heterogeneity as a major driver of disease progression under conditions of stress including hypoxia and nutrient deprivation, leading to metabolic reprogramming. We therefore advance our understanding in identifying the underlying mechanisms that interfere with the crosstalk between the extracellular matrix components and tumor cells that define the mechanics of tumor growth and metastasis. The bilateral interaction between the heterogeneous tumor microenvironment and PDAC cells serves as another important contributor that characterizes the tumor-promoting or tumor-suppressing phenotypes providing an opportunity for an effective treatment regime. Furthermore, we highlight the dynamic reciprocating interplay between the stromal and immune cells that impact immune surveillance or immune evasion response and contribute towards a complex process of tumorigenesis. In summary, the review encapsulates the existing knowledge of the currently applied treatments for PDAC with emphasis on tumor heterogeneity, manifesting at multiple levels, impacting disease progression and therapy resistance under stress.

Estimating Metastatic Risk of Pancreatic Ductal Adenocarcinoma at Single-Cell Resolution

Pancreatic ductal adenocarcinoma (PDAC) is characterized by intra-tumoral heterogeneity, and patients are always diagnosed after metastasis. Thus, finding out how to effectively estimate metastatic risk underlying PDAC is necessary. In this study, we proposed scMetR to evaluate the metastatic risk of tumor cells based on single-cell RNA sequencing (scRNA-seq) data. First, we identified diverse cell types, including tumor cells and other cell types. Next, we grouped tumor cells into three sub-populations according to scMetR score, including metastasis-featuring tumor cells (MFTC), transitional metastatic tumor cells (TransMTC), and conventional tumor cells (ConvTC). We identified metastatic signature genes (MSGs) through comparing MFTC and ConvTC. Functional enrichment analysis showed that up-regulated MSGs were enriched in multiple metastasis-associated pathways. We also found that patients with high expression of up-regulated MSGs had worse prognosis. Spatial mapping of MFTC showed that they are preferentially located in the cancer and duct epithelium region, which was enriched with the ductal cells' associated inflammation. Further, we inferred cell-cell interactions, and observed that interactions of the ADGRE5 signaling pathway, which is associated with metastasis, were increased in MFTC compared to other tumor sub-populations. Finally, we predicted 12 candidate drugs that had the potential to reverse expression of MSGs. Taken together, we have proposed scMetR to estimate metastatic risk in PDAC patients at single-cell resolution which might facilitate the dissection of tumor heterogeneity.

Low Pre-ChemoradiotherapyPan-Immune-Inflammation Value (PIV) Measures Predict Better Survival Outcomes in Locally Advanced Pancreatic Adenocarcinomas

Objective

This study sought to determine whether pretreatment pan-immune-inflammation value (PIV) could be used to predict prognosis in patients with locally advanced pancreatic adenocarcinoma (LA-PAC) following definitive concurrent chemoradiotherapy (C-CRT).

Methods

The outcomes of 178 LA-PAC patients who received definitive C-CRT were analyzed retrospectively. For all patients, the PIV was calculated using the peripheral blood platelet (P), monocyte (M), neutrophil (N), and lymphocyte (L) counts obtained on the first day of C-CRT: PIV=P×M×N÷L. The optimum cutoff values for PIV connected to progression-free (PFS) and overall survival (OS) results were sought using receiver operating characteristic (ROC) curve analysis. The OS and PFS differences between the PIV groups constituted the primary and secondary endpoints, respectively.

Results

ROC curve analysis indicated that the ideal PIV cutoff was 464 (AUC: 75.9%, sensitivity: 74.1%, specificity: 71.9%), which categorized patients into two groups based on PFS and OS results: low PIV (L-PIV; N = 69) and high PIV (H-PIV; N = 109). According to comparative survival analyses, patients in the L-PIV group had significantly longer median PFS (14.3 vs 7.3 months; HR: 3.04; P<0.001) and OS (25.9 vs 13.3 months; HR: 2.86; P<0.001) than those in the H-PIV group. Although none of the H-PIV patients could survive beyond 5 years, the estimated 5-year OS rate was 29.7% in the L-PIV cohort. In multivariate analyses, besides the L-PIV, N₀ nodal stage, and CA 19–9 ≤ 90 U/mL appeared to be the independent predictors of better PFS (P < 0.05 for each) and OS (P < 0.05 for each) results.

Conclusion

The present results indicated that pre-C-CRT L-PIV measures were associated with favorable median and long-term PFS and OS results in LA-PAC patients, suggesting that the PIV is a potent and independent novel prognostic biomarker.

Interplays of glucose metabolism and KRAS mutation in pancreatic ductal adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and deadliest cancer worldwide. The primary reasons for this are the lack of early detection methods and targeted therapy. Emerging evidence highlights the metabolic addiction of cancer cells as a potential target to combat PDAC. Oncogenic mutations of KRAS are the most common triggers that drive glucose uptake and utilization via metabolic reprogramming to support PDAC growth. Conversely, high glucose levels in the pancreatic microenvironment trigger genome instability and de novo mutations, including KRAS^G12D, in pancreatic cells through metabolic reprogramming. Here, we review convergent and diverse metabolic networks related to oncogenic KRAS mutations between PDAC initiation and progression, emphasizing the interplay among oncogenic mutations, glucose metabolic reprogramming, and the tumor microenvironment. Recognizing cancer-related glucose metabolism will provide a better strategy to prevent and treat the high risk PDAC population.

Effects of TP53 Mutations and miRs on Immune Responses in the Tumor Microenvironment Important in Pancreatic Cancer Progression

Approximately 90% of pancreatic cancers are pancreatic ductal adenocarcinomas (PDAC). PDAC is the fourth leading cause of cancer death world-wide. Therapies for PDAC are largely ineffective due to the dense desmoplastic tumor microenvironment which prevents chemotherapeutic drugs and small molecule inhibitors from exerting effective anti-cancer effects. In this review, we will discuss the roles of TP53 and miRs on the PDAC tumor microenvironment and how loss of the normal functions of TP53 promote tumor progression. The TP53 gene is mutated in approximately 50% of pancreatic cancers. Often, these TP53 mutations are point mutations which confer additional functions for the TP53 proteins. These are called gain of function (GOF) mutations (mut). Another class of TP53 mutations are deletions which result in loss of the TP53 protein; these are referred to TP53-null mutations. We have organized this review into various components/properties of the PDAC microenvironment and how they may be altered in the presence of mutant TP53 and loss of certain miR expression.

Cancer-inducing niche: the force of chronic inflammation

The growth of cancer tissue is thought to be considered driven by a small subpopulation of cells, so-called cancer stem cells (CSCs). CSCs are located at the apex of a hierarchy in a cancer tissue with self-renewal, differentiation and tumorigenic potential that produce the progeny in the tissue. Although CSCs are generally believed to play a critical role in the growth, metastasis, and recurrence of cancers, the origin of CSCs remains to be reconsidered. We hypothesise that, chronic diseases, including obesity and diabetes, establish the cancer-inducing niche (CIN) that drives the undifferentiated/progenitor cells into CSCs, which then develop malignant tumours in vivo. In this context, a CIN could be traced to chronic inflammation that involves long-lasting tissue damage and repair after being exposed to factors such as cytokines and growth factors. This must be distinguished from the cancer microenvironment, which is responsible for cancer maintenance. The concept of a CIN is most important for cancer prevention as well as cancer therapy.

Combination of LIGHT (TNFSF14)-Armed Myxoma Virus Pre-Loaded into ADSCs and Gemcitabine in the Treatment of Experimental Orthotopic Murine Pancreatic Adenocarcinoma

Simple Summary

Pancreatic ductal adenocarcinoma (PDAC) is a weakly immunogenic fatal neoplasm. Oncolytic viruses have dual anti-cancer properties including tumor-lysing and immune response-boosting effects and offer attractive alternative for PDAC management. Adipose-derived stem cells (AD-SCs) of mesenchymal origin were infected ex vivo with recombinant oncolytic myxoma virus (MYXV), which encodes murine LIGHT, also called tumor necrosis factor ligand superfamily member 14 (TNFSF14). ADSC-shielded virus were administered into murine pancreatic cancer lesions that had been induced orthotopically in immunocompetent mice. Ensuing oncolysis and the activation of anti-tumor immune responses provided significant survival benefit. Although adjunct therapy with gemcitabine improved the cytolytic killing of pancreatic cancer cells in vitro, it induced no additional survival advantage in this model in vivo.

Abstract

Pancreatic ductal adenocarcinoma (PDAC) is a deadly neoplasm. Oncolytic viruses have tumorolytic and immune response-boosting effects and present great potential for PDAC management. We used LIGHT-armed myxoma virus (vMyx-LIGHT) loaded ex vivo into human adipose-derived mesenchymal stem cells (ADSCs) to evaluate murine PDAC treatment in conjunction with gemcitabine (GEM). The cytotoxicity of this treatment was confirmed in vitro using human and murine pancreatic cancer cell cultures, which were more sensitive to the combined approach and largely destroyed. Unlike cancer cells, ADSCs sustain significant viability after infection. The in vivo administration of vMyx-LIGHT-loaded ADSCs and gemcitabine was evaluated using immunocompetent mice with induced orthotopic PDAC lesions. The expression of virus-encoded LIGHT increased the influx of T cells to the tumor site. Shielded virus followed by gemcitabine improved tumor regression and survival. The addition of gemcitabine slightly compromised the adaptive immune response boost obtained with the shielded virus alone, conferring no survival benefit. ADSCs pre-loaded with vMyx-LIGHT allowed the effective transport of the oncolytic construct to PDAC lesions and yielded significant immune response; additional GEM administration failed to improve survival. In view of our results, the delivery of targeted/shielded virus in combination with TGF-β ablation and/or checkpoint inhibitors is a promising option to improve the therapeutic effects of vMyx-LIGHT/ADSCs against PDAC in vivo.

Development and external validation of a nomogram with inflammatory markers for predicting invasiveness of intraductal papillary mucinous neoplasm of pancreas

ABSTRACT

Recent studies have reported that inflammatory markers, such as neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, and advanced lung cancer inflammation index, are associated with invasiveness of intraductal papillary mucinous neoplasm (IPMN). This study aimed to develop and validate a new nomogram that includes inflammatory markers for predicting the invasiveness of IPMN.The data of 365 patients who underwent surgical resection for IPMN at 4 centers between 1995 and 2016 were retrospectively reviewed to develop a new nomogram. For external validation, a separate patient cohort was used. The predictive ability of the nomogram was evaluated using the area under the receiver operating characteristic curve.The new nomogram was developed using the following variables which were identified as risk factors for invasive IPMN: body mass index, preoperative serum bilirubin level, carbohydrate antigen 19-9, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, advanced lung cancer inflammation index, main duct type, presence of solid portion, and tumor size. After external validation, the area under the curve value was 0.649 (95% CI: 0.578-0.720, P < .001).To the best of our knowledge, this study is the first to predict and externally validate the invasiveness in IPMN using inflammatory markers. Further research is necessary to improve predictability of the model for selecting patients for surgical resection.

Fungal mycobiome drives IL-33 secretion and type 2 immunity in pancreatic cancer

TH2 cells and innate lymphoid cells 2 (ILC2) can stimulate tumor growth by secreting pro-tumorigenic cytokines such as interleukin-4 (IL-4), IL-5, and IL-13. However, the mechanisms by which type 2 immune cells traffic to the tumor microenvironment are unknown. Here, we show that oncogenic KrasG12D increases IL-33 expression in pancreatic ductal adenocarcinoma (PDAC) cells, which recruits and activates TH2 and ILC2 cells. Correspondingly, cancer-cell-specific deletion of IL-33 reduces TH2 and ILC2 recruitment and promotes tumor regression. Unexpectedly, IL-33 secretion is dependent on the intratumoral fungal mycobiome. Genetic deletion of IL-33 or anti-fungal treatment decreases TH2 and ILC2 infiltration and increases survival. Consistently, high IL-33 expression is observed in approximately 20% of human PDAC, and expression is mainly restricted to cancer cells. These data expand our knowledge of the mechanisms driving PDAC tumor progression and identify therapeutically targetable pathways involving intratumoral mycobiome-driven secretion of IL-33.

Postchemoradiotherapy Neutrophil-to-Lymphocyte Ratio Predicts Distant Metastasis and Survival Results in Locally Advanced Pancreatic Cancers

MATERIALS AND METHODS

Our retrospective research included a sum of 126 LAPAC patients who received CCRT. The NLR was calculated for each patient based on the complete blood count test results obtained on the last day of the CCRT. The availability of optimal cutoff(s) that might dichotomize the whole cohort into two groups with significantly different clinical outcomes was searched using receiver operating characteristic (ROC) curve analysis. Primary and secondary endpoints were the potential association between the post-CCRT NLR measures and distant metastasis-free survival (DMFS) and overall survival (OS) outcomes.

RESULTS

The median follow-up duration was 14.7 months (range: 2.4-94.5). The median and 3-year OS and DMFS rates for the whole group were 15.3 months (95% confidence interval: 12.4-18.2) and 14.5%, and 8.7 months (95% CI: 6.7-10.7) and 6.3% separately. The ROC curve analysis findings separated the patients into two groups on a rounded NLR cutoff of 3.1 (area under the curve (AUC): 75.4%; sensitivity: 74.2%; specificity: 73.9%) for OS and DMFS: NLR <3.1 (N = 62) and NLR ≥3.1 (N = 64), respectively. Comparisons between the NLR groups displayed that the median OS (11.4 vs. 21.4 months; P < 0.001) and DMFS (6.0 vs. 16.0 months; P < 0.001) lengths were significantly shorter in the NLR ≥3.1 group than its NLR <3.1 counterparts, as well as the 3-year actuarial DM rate (79.7% vs. 50.0%; P=0.003). The N1-2 nodal stage, CA 19-9>90 U/mL, and NLR >3.1 were found to be independent predictors of poor prognosis in the multivariate analysis.

CONCLUSION

The present study found that the posttreatment NLR ≥3.1 was independently linked with a higher risk of DM and subsequent degraded survival outcomes in unresectable LAPAC patients managed with exclusive CCRT.

Circulating Inflammation Markers and Pancreatic Cancer Risk: A Prospective Case-Cohort Study in Japan

BACKGROUND

Previous prospective studies of associations between circulating inflammation-related molecules and pancreatic cancer risk have included limited numbers of markers.

METHODS

We conducted a case-cohort study nested within the Japan Public Health Center-based Prospective Study Cohort II. We selected a random subcohort (n = 774) from a total of 23,335 participants aged 40 to 69 years who returned a questionnaire and provided blood samples at baseline. During the follow-up period from 1993 to 2010, we identified 111 newly diagnosed pancreatic cancer cases, including one case within the subcohort. Plasma concentrations of 62 inflammatory markers of chemokines, cytokines, and growth factors were measured by a Luminex fluorescent bead-based assay. Cox regression models were applied to estimate HR and 95% confidence intervals (CI) for pancreatic cancer risk for quartiles of marker levels adjusted for potential confounders.

RESULTS

The HR (95% CI) for the highest versus the lowest category of C-C motif ligand chemokine 8/monocyte chemoattractant protein 2 (CCL8/MCP2) was 2.03 (1.05-3.93; P trend = 0.048). After we corrected for multiple comparisons, none of the examined biomarkers were associated with pancreatic cancer risk at P-value <0.05.

CONCLUSIONS

We found no significant associations between 62 inflammatory markers and pancreatic cancer risk.

IMPACT

The suggestive association with circulating levels of leukocyte recruiting cytokine CCL8/MCP2 may warrant further investigation.

Epithelial memory of inflammation limits tissue damage while promoting pancreatic tumorigenesis

Inflammation is a major risk factor for pancreatic ductal adenocarcinoma (PDAC). When occurring in the context of pancreatitis, KRAS mutations accelerate tumor development in mouse models. We report that long after its complete resolution, a transient inflammatory event primes pancreatic epithelial cells to subsequent transformation by oncogenic KRAS. Upon recovery from acute inflammation, pancreatic epithelial cells display an enduring adaptive response associated with sustained transcriptional and epigenetic reprogramming. Such adaptation enables the reactivation of acinar-to-ductal metaplasia (ADM) upon subsequent inflammatory events, thereby limiting tissue damage through a rapid decrease of zymogen production. We propose that because activating mutations of KRAS maintain an irreversible ADM, they may be beneficial and under strong positive selection in the context of recurrent pancreatitis.

The Prognostic Significance of Novel Pancreas Cancer Prognostic Index in Unresectable Locally Advanced Pancreas Cancers Treated with Definitive Concurrent Chemoradiotherapy

Purpose

We evaluated the prognostic quality of the novel pancreas cancer prognostic index (PCPI), a combination of CA 19-9 and systemic inflammation response index (SIRI), on the outcomes of locally advanced pancreas adenocarcinoma (LAPAC) patients who received concurrent chemoradiotherapy (C-CRT).

Methods

This retrospective analysis covered 152 unresectable LAPAC patients treated from 2007 to 2019. Receiver operating characteristic (ROC) curve analysis was used to define ideal cutoff thresholds for the pretreatment CA 19-9 and SIRI measurements, individually. The associations between the PCPI groups and progression-free- (PFS) and overall survival (OS) comprised the respective primary and secondary endpoints.

Results

The ROC curve analysis distinguished the respective rounded optimal cutoffs at 91 U/m/L (< versus ≥90) and 1.8 (< versus ≥1.8) for CA 19-9 and SIRI, arranging the study cohort into two significantly different survival groups for each, with resultant four likely groups: Group-1: CA 19-9<90 U/m/L and SIRI<1.8, Group-2: CA 19-9<90 U/m/L but SIRI≥1.8, Group-3: CA 19-9≥90 U/m/L but SIRI<1.8, and Group-4: CA 19-9≥90 U/m/L and SIRI≥1.8. Since the PFS (P=0.79) and OS (P=0.86) estimates of the groups 2 and 3 were statistically indistinct, we merged them as one group and created the novel three-tiered PCPI: PCPI-1: CA 19-9<90 U/m/L and SIRI<1.8, PCPI-2: CA 19-9<90 U/m/L but SIRI≥1.8 or CA 19-9≥90 U/m/L but SIRI<1.8, and PCPI-3: CA 19-9≥90 U/m/L and SIRI≥1.8, respectively. Comparative analyses unveiled that the PCPI-1 and PCPI-3 groups had the respective best and worst PFS (17.0 versus 7.5 versus 4.4 months; P<0.001) and OS (26.1 versus 15.1 versus 7.4 months; P<0.001) outcomes, while the PCPI-2 group posed in between. The multivariate analysis outcomes confirmed the novel three tired PCPI’s independent prognostic significance on either of the PFS [HR: 5.38 (95% confidence interval (CI): 4.96-5.80); P<0.001)] and OS [HR: 5.67 (95% CI: 5.19-6.15); P<0.001] endpoints, separately.

Conclusion

The new PCPI introduced here can be used as an independent and reliable prognostic indicator to divide LAPAC patients into three subgroups with discrete survival results.

NF-κB and Pancreatic Cancer; Chapter and Verse

Pancreatic Ductal Adenocarcinoma (PDAC) is one of the world's most lethal cancers. An increase in occurrence, coupled with, presently limited treatment options, necessitates the pursuit of new therapeutic approaches. Many human cancers, including PDAC are initiated by unresolved inflammation. The transcription factor NF-κB coordinates many signals that drive cellular activation and proliferation during immunity but also those involved in inflammation and autophagy which may instigate tumorigenesis. It is not surprising therefore, that activation of canonical and non-canonical NF-κB pathways is increasingly recognized as an important driver of pancreatic injury, progression to tumorigenesis and drug resistance. Paradoxically, NF-κB dysregulation has also been shown to inhibit pancreatic inflammation and pancreatic cancer, depending on the context. A pro-oncogenic or pro-suppressive role for individual components of the NF-κB pathway appears to be cell type, microenvironment and even stage dependent. This review provides an outline of NF-κB signaling, focusing on the role of the various NF-κB family members in the evolving inflammatory PDAC microenvironment. Finally, we discuss pharmacological control of NF-κB to curb inflammation, focussing on novel anti-cancer agents which reinstate the process of cancer cell death, the Smac mimetics and their pre-clinical and early clinical trials.

Cohort profile and heritability assessment of familial pancreatic cancer: a nation-wide study

BACKGROUND

Familial Pancreatic Cancer (FPC) is responsible for up to 10% of all cases of pancreatic ductal adenocarcinoma (PDAC). Individuals predisposed for FPC have an estimated lifetime risk of 16-39% of developing PDAC. While heritability of PDAC has been estimated to be 36% in a Nordic twin study, no heritability estimate specific on FPC has been reported.

METHODS

A national cohort of Danish families with predisposition for FPC is currently included in a screening program for PDAC at Odense University Hospital. Family members included in the screening program were interviewed for pedigree data including: cases of PDAC among first-degree relatives (FDRs) and number of affected/unaffected siblings. Heritability for FPC in the predisposed families was assessed by doubling the estimated intra-class correlation coefficient (ICC) from a random intercept logistic model fitted to data on FDRs.

RESULTS

Among families with predisposition for FPC, 83 cases of PDAC were identified. The median age at diagnosis of PDAC was 66 years, and median time from diagnosis to death was 7.6 months. A total of 359 individuals were found as unaffected FDRs of the 83 PDAC cases. The retrieved FDRs included a total of 247 individuals in sibship and 317 individuals in parent-offspring relatedness. We estimated an ICC of 0.25, corresponding to a narrow sense additive heritability estimate of 0.51 in the FPC family cohort.

CONCLUSION

We have established a nation-wide cohort of FPC families to facilitate clinical and genetic studies on FPC. The estimated heritability of 51% prominently underlines a strong genetic background of FPC.

Endogenous and Therapeutic Estrogens: Maestro Conductors of the Microenvironment of ER+ Breast Cancers

Estrogen receptor alpha (ERα) marks heterogeneous breast cancers which display a repertoire of somatic genomic mutations and an immune environment that differs from other breast cancer subtypes. These cancers also exhibit distinct biological behaviors; despite an overall better prognosis than HER2+ or triple negative breast cancers, disseminated dormant cells can lead to disease recurrence decades after the initial diagnosis and treatment. Estrogen is the best studied driver of these cancers, and antagonism or reduction of estrogen activity is the cornerstone of therapeutic approaches. In addition to reducing proliferation of ERα+ cancer cells, these treatments also alter signals to multiple other target cells in the environment, including immune cell subpopulations, cancer-associated fibroblasts, and endothelial cells via several distinct estrogen receptors. In this review, we update progress in our understanding of the stromal cells populating the microenvironments of primary and metastatic ER+ tumors, the effects of estrogen on tumor and stromal cells to modulate immune activity and the extracellular matrix, and net outcomes in experimental and clinical studies. We highlight new approaches that will illuminate the unique biology of these cancers, provide the foundation for developing new treatment and prevention strategies, and reduce mortality of this disease.

The Roles of Frequently Mutated Genes of Pancreatic Cancer in Regulation of Tumor Microenvironment

Pancreatic ductal adenocarcinoma has extremely high malignancy and patients with pancreatic ductal adenocarcinoma have dismal prognosis. The failure of pancreatic ductal adenocarcinoma treatment is largely due to the tumor microenvironment, which is featured by ample stromal cells and complicated extracellular matrix. Recent genomic analysis revealed that pancreatic ductal adenocarcinoma harbors frequently mutated genes including KRAS, TP53, CDKN2A, and SMAD4, which can widely alter cellular processes and behaviors. As shown by accumulating studies, these mutant genes may also change tumor microenvironment, which in turn affects pancreatic ductal adenocarcinoma progression. In this review, we summarize the role of such genetic mutations in tumor microenvironment regulation and potential mechanisms.

Expression of POU2F3 Transcription Factor Control Inflammation, Immunological Recruitment and Metastasis of Pancreatic Cancer in Mice

Simple Summary

The presence and the role of TUFT cells in pancreatic ductal adenocarcinoma (PDAC) is discussed. Therefore, we decided to inactivate the POU2F3 gene, which is essential for TUFT cells development, in an aggressive PDAC mice model known as PDX1-Cre;LSL-Kras^G12D;Ink4a^fl/fl. Morphological and molecular analysis of POU2F3-deleted PDAC show not significant changes in tumors growth and survival of animals although it promotes EMT. Remarkably, we observed that in POU2F3-deleted animals the lack of TUFT cells prevents metastasis formation and strongly modifies the immunological and inflammatory landscape.

Abstract

TUFT cells have been described as strong modulators of inflammatory cells in several tissues including pancreas. TUFT cells, also known as DCLK1⁺ cells, are dependent of the transcriptional factor POU2F3. Several works report DCLK1⁺ cells in early stages of PDAC development suggesting an important role of TUFT cells in PDAC development. Therefore, we developed a mice model (PDX1-Cre;Kras^G12D;Ink4a^fl/fl), known as PKI model, deficient or not of POU2F3. In this animal model, deficiency of POU2F3 results in the absence of TUFT cells in PDAC as expected. Although, tumor development and growth are not significantly influenced, the development of liver metastasis was almost completely inhibited in POU2F3-deficient mice. Surprisingly, the absence of metastasis was associated with a higher expression of epithelial-to-mesenchymal transition markers, but to a lower inflammatory microenvironment suggesting that inflammation influences metastasis production more than epithelial-to-mesenchymal transition in this animal model. We can conclude that POU2F3 could be a new therapeutic target for control PDAC progression.

Low Systemic Inflammation Response Index Predicts Good Prognosis in Locally Advanced Pancreatic Carcinoma Patients Treated with Concurrent Chemoradiotherapy

Background

We investigated the prognostic significance of pretreatment systemic inflammation response index (SIRI) in locally advanced pancreatic carcinoma (LAPC) patients treated with concurrent chemoradiotherapy (CRT).

Methods

Present retrospective cohort analysis investigated consecutive 154 LAPC patients who received radical CRT. The SIRI was defined as: SIRI = neutrophil × monocyte/lymphocyte counts. Ideal SIRI cutoff(s) influencing overall survival (OS) and progression-free survival (PFS) results were sought by using receiver operating characteristic (ROC) curve analysis. The primary endpoint was the interaction between the SIRI and OS results.

Results

The median follow-up, PFS, and OS durations were 14.3 (range: 2.9-74.6), 7.9 [%95 confidence interval (CI): 5.7-10.1), and 14.7 months (%95 CI: 11.4-18.0) for the entire cohort, respectively. ROC curve analyses determined the ideal SIRI cutoff that exhibiting a significant link with OS and PFS outcomes at the rounded 1.6 point (AUC: 74.3%; sensitivity: 73.8%; specificity: 70.1%).The SIRI <1.6 patients (N = 58) had significantly superior median PFS (13.8 versus 6.7 months; P < 0.001) and OS (28.6 versus 12.6 months; P < 0.001) lengths than SIRI ≥1.6 patients (N = 96), respectively. Although the N0 (versus N1; P < 0.05) and CA 19-9 ≤90 U/mL (versus >90 U/mL) appeared as the other significant associates of better OS and PFS in univariate analyses, yet the results of multivariate analyses confirmed the SIRI <1.6 as the independent indicator of superior OS and PFS (P < 0.001 for each).

Conclusion

Pretreatment SIRI is a novel independent prognosticator that may further enhance the conventional tumor-node-metastases staging system in a more precise prediction of the OS and PFS outcomes of LAPC patients after radical CRT.

Multimodal radiomics and cyst fluid inflammatory markers model to predict preoperative risk in intraductal papillary mucinous neoplasms

Purpose: Our paper contributes to the burgeoning field of surgical data science. Specifically, multimodal integration of relevant patient data is used to determine who should undergo a complex pancreatic resection. Intraductal papillary mucinous neoplasms (IPMNs) represent cystic precursor lesions of pancreatic cancer with varying risk for malignancy. We combine previously defined individual models of radiomic analysis of diagnostic computed tomography (CT) with protein markers extracted from the cyst fluid to create a unified prediction model to identify high-risk IPMNs. Patients with high-risk IPMN would be sent for resection, whereas patients with low-risk cystic lesions would be spared an invasive procedure. Approach: Retrospective analysis of prospectively acquired cyst fluid and CT scans was undertaken for this study. A predictive model combining clinical features with a cyst fluid inflammatory marker (CFIM) was applied to patient data. Quantitative imaging (QI) features describing radiomic patterns predictive of risk were extracted from scans. The CFIM model and QI model were combined into a single predictive model. An additional model was created with tumor-associated neutrophils (TANs) assessed by a pathologist at the time of resection. Results: Thirty-three patients were analyzed (7 high risk and 26 low risk). The CFIM model yielded an area under the curve (AUC) of 0.74. Adding the QI model improved performance with an AUC of 0.88. Combining the CFIM, QI, and TAN models further increased performance to an AUC of 0.98. Conclusions: Quantitative analysis of routinely acquired CT scans combined with CFIMs provides accurate prediction of risk of pancreatic cancer progression. Although a larger cohort is needed for validation, this model represents a promising tool for preoperative assessment of IPMN.

Oncogenic KRAS-Driven Metabolic Reprogramming in Pancreatic Cancer Cells Utilizes Cytokines from the Tumor Microenvironment

A hallmark of pancreatic ductal adenocarcinoma (PDAC) is an exuberant stroma comprised of diverse cell types that enable or suppress tumor progression. Here, we explored the role of oncogenic KRAS in protumorigenic signaling interactions between cancer cells and host cells. We show that KRAS mutation (KRAS*) drives cell-autonomous expression of type I cytokine receptor complexes (IL2rγ-IL4rα and IL2rγ-IL13rα1) in cancer cells that in turn are capable of receiving cytokine growth signals (IL4 or IL13) provided by invading Th2 cells in the microenvironment. Early neoplastic lesions show close proximity of cancer cells harboring KRAS* and Th2 cells producing IL4 and IL13. Activated IL2rγ-IL4rα and IL2rγ-IL13rα1 receptors signal primarily via JAK1-STAT6. Integrated transcriptomic, chromatin occupancy, and metabolomic studies identified MYC as a direct target of activated STAT6 and that MYC drives glycolysis. Thus, paracrine signaling in the tumor microenvironment plays a key role in the KRAS*-driven metabolic reprogramming of PDAC. SIGNIFICANCE: Type II cytokines, secreted by Th2 cells in the tumor microenvironment, can stimulate cancer cell-intrinsic MYC transcriptional upregulation to drive glycolysis. This KRAS*-driven heterotypic signaling circuit in the early and advanced tumor microenvironment enables cooperative protumorigenic interactions, providing candidate therapeutic targets in the KRAS* pathway for this intractable disease.

Pancreatic Cancer: A Review of Risk Factors, Diagnosis, and Treatment

This review aims to summarize the latest knowledge on factors, diagnosis, and treatment of pancreatic cancer, and aims to promote further research on this under-studied malignant tumor. At present, we urgently need to identify high-risk patients with precancerous diseases through screening approaches, so that medical professionals and the general public may better understand prevention strategies or early detection measures. Pancreatic cancer is a highly invasive malignant tumor with a fatal risk, mainly seen in men and older adults (60-85 years old). Pancreatic cancer is now increasingly observed in young patients. Because the disease has no early symptoms and can quickly invade surrounding tissues and organs, it is one of the deadliest cancers. With a view to identify the important factors for the development of pancreatic cancer, previous studies have found that smoking, alcohol, and chronic pancreatitis are considered high-risk factors. Recent studies have shown that abnormal metabolism of human microorganisms, blood type, and glucose and lipid levels are also important factors in the development of pancreatic cancer. Identifying early diagnosis options is an important way to improve detection and survival rates of pancreatic cancer. None of the many tumor markers associated with pancreatic cancer are highly specific, which also indicates further research is required to improve the early detection rate. Future directions in terms of treatment evaluating the relationship between the microbiology-free system and immunotherapy will bring a major breakthrough and is expected to bring exciting clinical applications in improving the life-cycle of pancreatic cancer patients.

Prognostic Usefulness Of Advanced Lung Cancer Inflammation Index In Locally-Advanced Pancreatic Carcinoma Patients Treated With Radical Chemoradiotherapy

Background/Aims

Previously advanced lung cancer inflammation index (ALI) has been demonstrated to have prognostic utility in the stratification of patients into distinctive survival groups, but the prognostic value of ALI has never been explored in the setting of locally advanced pancreatic carcinomas (LAPC) treated with concurrent chemoradiotherapy (CCRT). Hence, we aimed to investigate the prognostic value of pre-treatment ALI in LAPC patients who underwent radical CCRT.

Methods

Present retrospective cohort analysis incorporated 141 LAPC patients who received radical CCRT. Accessibility of baseline ALI cutoff(s) impacting survival outcomes was sought by receiver operating characteristic (ROC) curve analysis. Interaction between the ALI and overall- (OS) and progression-free survival (PFS) comprised our primary and secondary endpoints, respectively.

Results

At a median follow-up of 14.4 months (range: 3.2–74.2), the median PFS and OS were 7.5 (%95 CI: 5.9–9.1) and 14.6 months (%95 CI: 11.6–17.6), respectively. ROC curve analyses set the ideal ALI cutoff value at 25.3 (AUC: 75.6%; sensitivity: 72.7%; specificity: 70.3%) that exhibited significant associations with both the OS and PFS results. Patient stratification into two groups per ALI [≤25.3 (N=75) versus>25.3 (N=66)] showed that the ALI>25.3 group had significantly superior median OS (25.8 versus 11.4 months; P<0.001) and PFS (15.9 versus 6.0 months; P<0.001) durations than its ALI≤25.3 counterpart. Other factors exhibiting significantly better OS and PFS rates were N₀ stage (versus N1; P<0.05 for each endpoint) and CA 19-9 ≤90 U/mL (versus >90 U/mL; P<0.05 for each endpoint), respectively. These three factors were additionally asserted to be independent indicators of longer OS (P<0.05 for each) and PFS (P<0.05 for each) in multivariate analyses.

Conclusion

Results of this hypothesis-generating research proposed the pre-CCRT ALI as a novel robust associate of OS and PFS outcomes for LAPC patients undergoing CCRT.

Inflammation, Biomarkers and Immuno-Oncology Pathways in Pancreatic Cancer

It is estimated that pancreatic cancer will be the second leading cause of cancer-related deaths globally by 2030, highlighting the ongoing lack of effective treatment options for this devastating condition. There is a lack of reliable prognostic or predictive markers in pancreatic cancer to guide management decisions, whether for systemic chemotherapy, molecularly targeted therapies, or immunotherapies. To date, the results for targeted agents and immunotherapies in unselected populations of chemo-refractory pancreatic cancer have not met expectations. The reasons for this lack of efficacy of immunotherapy in pancreatic cancer are not completely understood. The challenges in pancreatic cancer include the physical barrier created by the dense desmoplastic stroma surrounding the tumor, chemokine-mediated exclusion of T cells, relatively poorer antigenicity compared to other solid tumors, paucity of infiltrating T cells within the tumor, ultimately leading to an immunosuppressive microenvironment. A better understanding of the role of inflammation in pancreatic cancer, its tumor microenvironment and individualized patient-related features, be they molecular, clinical or histopathological, would enable a more effective tailored approach to the management of pancreatic cancer. In this review, the role of inflammation, the immune tumor microenvironment and potential immune biomarkers in pancreatic cancer are explored.

Neoadjuvant Chemotherapy Based on Abraxane/Human Neutrophils Cytopharmaceuticals with Radiotherapy for Gastric Cancer

Gastric cancer remains one of the most lethal cancers with high incidence and mortality worldwide. The majority of gastric cancer patients are those who have first been diagnosed in advanced stage, in which the standard chemo-radiotherapy produces limited benefit along with severe general toxicity, thus the demand for improved therapeutic efficacy and decreased side effects drives the development of novel therapeutic strategies. Here, a neoadjuvant chemotherapy based on Abraxane/human neutrophils (NEs) cytopharmaceuticals with radiotherapy is presented for effective cancer treatment. Human NEs, the most abundant white blood cells in peripheral blood, are developed to carry Abraxane, the commercial albumin-bound paclitaxel nanoparticle, to form cytopharmaceuticals (Abraxane/NEs) which have been confirmed to maintain the intrinsic functions of human NEs. The modest radiation is applied not only to exert tumor disruption, but also to increase the release of inflammatory factors which guide the NEs homing to the tumoral sites. These amplified inflammatory factors at tumor sites excessively activate Abraxane/NEs to form neutrophil extracellular traps, along with a burst release of Abraxane to induce superior tumor suppression. This adjuvant chemo-radiotherapy based on cytopharmaceuticals may provide new opportunities for advanced cancer treatment, which reveals the huge clinical potential of human neutrophils as drug delivery vectors.

NARCA: A novel prognostic scoring system using neutrophil-albumin ratio and Ca19-9 to predict overall survival in palliative pancreatic cancer

BACKGROUND AND OBJECTIVES

Several serum based-markers and ratios have been investigated for their prognostic value in pancreatic ductal adenocarcinoma (PDAC). This cohort study aimed to combine these into a novel prognostic scoring system.

METHODS

A retrospective cohort study was performed on 145 patients with unresectable histologically-confirmed PDAC. Based on the existing literature the following markers were investigated: neutrophil-lymphocyte ratio (NLR), neutrophil-albumin ratio (NAR), platelet-lymphocyte ratio (PLR), fibrinogen, and Ca19-9. These values were dichotomized about their medians for Kaplan-Meier and Cox regression analysis.

RESULTS

Univariate Cox regression revealed statistically significant prognostic value for: NLR, NAR, PLR, fibrinogen, and Ca19-9. When combining these using Cox regression analysis adjusting for other prognostic indicators, only NAR (hazard ratios [HR] = 3.174, P = 0.022) and Ca19-9 (HR = 2.697, P = 0.031) were independent predictors of survival. Combining NAR and Ca19-9 we split the cohort into three "NARCA" groups: NARCA0 = NAR ≤ 0.13 and Ca19-9 ≤ 770, NARCA1 = either NAR > 0.13 or Ca19-9 >770, NARCA2 = NAR > 0.13 and Ca19-9 > 770. Median survival was 20.5, 9.7 and 4.1 months in NARCA0, 1, and 2 respectively ( P < 0.0005, log-rank test). A separate validation cohort confirmed the prognostic significance of the score ( P = 0.048).

CONCLUSIONS

Combining NAR and Ca19-9 into a prognostic score allows stratification of unresectable PDAC patients into groups with significantly different overall survival.

Strategies for Increasing Pancreatic Tumor Immunogenicity

Immunotherapy has changed the standard of care for multiple deadly cancers, including lung, head and neck, gastric, and some colorectal cancers. However, single-agent immunotherapy has had little effect in pancreatic ductal adenocarcinoma (PDAC). Increasing evidence suggests that the PDAC microenvironment is comprised of an intricate network of signals between immune cells, PDAC cells, and stroma, resulting in an immunosuppressive environment resistant to single-agent immunotherapies. In this review, we discuss differences between immunotherapy-sensitive cancers and PDAC, the complex interactions between PDAC stroma and suppressive tumor-infiltrating cells that facilitate PDAC development and progression, the immunologic targets within these complex networks that are druggable, and data supporting combination drug approaches that modulate multiple PDAC signals, which should lead to improved clinical outcomes. Clin Cancer Res; 23(7); 1656-69. ©2017 AACRSee all articles in this CCR Focus section, "Pancreatic Cancer: Challenge and Inspiration."

A new combined criterion to better predict malignant lesions in patients with pancreatic cystic neoplasms

Objective:

Cystic lesions of the pancreas have been increasingly recognized. Some lesions exhibit benign behavior, while others have unequivocal malignant potential. Thus, accurate identification of malignancy in patients diagnosed with pancreatic cystic neoplasms (PCNs) remains a major challenge. The aim of this study was to define a combined criterion to better predict malignant lesions in patients with PCNs.

Methods:

We retrospectively analyzed 165 patients who underwent resection of PCNs from October 2011 to May 2017. The relationship among malignancy and serum carbohydrate antigen 19-9 (CA19-9), preoperative neutrophil-to-lymphocyte ratio (NLR), and the presence of enhanced solid component on imaging was analyzed.

Results:

NLR before surgery in patients with malignant PCNs (2.81±2.14) was significantly higher than that in patients diagnosed with pancreatic neuroendocrine tumor (1.90±0.69, P=0.013) or healthy volunteers (1.40±0.48; P<0.001). Serum CA19-9 ≥39 U/mL, NLR >1.976 and presence of enhanced solid component were independent predictors of PCN malignancy. A combined criterion meeting any two or more of the three elements including CA19-9 ≥39 U/mL, NLR >1.976, and presence of enhanced solid component on computed tomography imaging is an indicator with a high positive predictive value of 80.5% and a high negative predictive value of 87.9%, and thus, represents a highly accurate test (86.1%).

Conclusions:

The new combined criterion is an effective predictor of tumor malignancy in patients with PCNs.

LIF Drives Neural Remodeling in Pancreatic Cancer and Offers a New Candidate Biomarker

Pancreatic ductal adenocarcinoma (PDAC) is characterized by extensive stroma and pathogenic modifications to the peripheral nervous system that elevate metastatic capacity. In this study, we show that the IL6-related stem cell-promoting factor LIF supports PDAC-associated neural remodeling (PANR). LIF was overexpressed in tumor tissue compared with healthy pancreas, but its receptors LIFR and gp130 were expressed only in intratumoral nerves. Cancer cells and stromal cells in PDAC tissues both expressed LIF, but only stromal cells could secrete it. Biological investigations showed that LIF promoted the differentiation of glial nerve sheath Schwann cells and induced their migration by activating JAK/STAT3/AKT signaling. LIF also induced neuronal plasticity in dorsal root ganglia neurons by increasing the number of neurites and the soma area. Notably, injection of LIF-blocking antibody into PDAC-bearing mice reduced intratumoral nerve density, supporting a critical role for LIF function in PANR. In serum from human PDAC patients and mouse models of PDAC, we found that LIF titers positively correlated with intratumoral nerve density. Taken together, our findings suggest LIF as a candidate serum biomarker and diagnostic tool and a possible therapeutic target for limiting the impact of PANR in PDAC pathophysiology and metastatic progression.Significance: This study suggests a target to limit neural remodeling in pancreatic cancer, which contributes to poorer quality of life and heightened metastatic progression in patients. Cancer Res; 78(4); 909-21. ©2017 AACR.

Differential role of Interleukin-1 and Interleukin-6 in K-Ras-driven pancreatic carcinoma undergoing mesenchymal transition

K-Ras mutations are a hallmark of human pancreatic adenocarcinoma (PDAC) and epithelial-mesenchymal-transition (EMT) is a driver of progression. Oncogenic K-Ras causes the constitutive activation of NF-kB and the switch-on of an inflammatory program, which further fuels NF-kB and STAT3 activation. In this study we investigated how inflammatory pathways triggered by oncogenic K-Ras are regulated in human pancreatic cancer cells with distict epithelial or mesenchymal phenotype. Our results demonstrate that in cells with epithelial features, K-Ras driven inflammation is under the control of IL-1, while in cells undergoing EMT, is IL-1 independent. In pancreatic tumor cells with EMT phenotype, treatment with IL-1R antagonist (Anakinra) did not inhibit inflammatory cytokine production and tumor growth in mice. In these cells IL-6 is actively transcribed by the EMT transcription factor TWIST. Targeting of mesenchymal pancreatic tumors in vivo with anti-IL-6RmAb (RoActemra) successfully decreased tumor growth in immunodeficient mice, inhibited the inflammatory stroma and NF-kB-p65 and STAT3 phosphorylation in cancer cells. The results confirm that IL-1 is an important driver of inflammation in epithelial pancreatic tumors; however, tumor cells undergoing EMT will likely escape IL-1R inhibition, as IL-6 is continuously transcribed by TWIST. These findings have implications for the rational targeting of inflammatory pathways in human pancreatic cancer.

The receptor for advanced glycation end products: A fuel to pancreatic cancer

The receptor for advanced glycation end products (RAGEs) was first illustrated in the year 1992. RAGE is a single-transmembrane and multi-ligand component of the immunoglobulin protein super family. The engagement of RAGE turns out to an establishment of numerous intracellular signalling mechanisms resulting in the progression and perpetuation of many types of cancer including, the pancreatic cancer. The present review primarily focuses on the multi-ligand activation of RAGEs leading to the downstream signalling cascade activation. The kick start of the RAGEs activation leads to the several anomalies and includes multiple types of cancers. The RAGE expression correlates well with the survival of pancreatic cancer cells leading to the myeloid response. RAGEs assist in the tumourogenesis which enhance and thrive to its fullest in the stressed tumour microenvironment. An improved perceptive of its involvement in pancreatic cancer may offer novel targets for tumour supervision and risk measurement.

Inflammation and Epithelial-Mesenchymal Transition in Pancreatic Ductal Adenocarcinoma: Fighting Against Multiple Opponents

Pancreatic ductal adenocarcinoma (PDAC) is the most common type of pancreatic cancer and one of the most lethal human cancers. Inflammation is a critical component in PDAC initiation and progression. Inflammation also contributes to the aggressiveness of PDAC indirectly via induction of epithelial-mesenchymal transition (EMT), altogether leading to enhanced resistance to chemotherapy and poor survival rates. This review gives an overview of the key pro-inflammatory signaling pathways involved in PDAC pathogenesis and discusses the role of inflammation in induction of EMT and development of chemoresistance in patients with PDAC.

Aspirin in pancreatic cancer: chemopreventive effects and therapeutic potentials

Pancreatic cancer is one of the most aggressive malignancies with dismal prognosis. Recently, aspirin has been found to be an effective chemopreventive agent for many solid tumors. However, the function of aspirin use in pancreatic cancer largely remains unknown. We herein argued that aspirin could also lower the risk of pancreatic cancer. Importantly, aspirin assumes pleiotropic effects by targeting multiple molecules. It could further target the unique tumor biology of pancreatic cancer and modify the cancer microenvironment, thus showing remarkable therapeutic potentials. Besides, aspirin could reverse the chemoradiation resistance by repressing tumor repopulation and exert synergistic potentials with metformin on pancreatic cancer chemoprevention. Moreover, aspirin secondarily benefits pancreatic cancer patients through modestly reducing cancer pain and the risk of venous thromboembolism. Furthermore, new aspirin derivatives and delivery systems might help to improve risk-to-benefit ratio. In brief, aspirin is a promising chemopreventive agent and exerts significant therapeutic potentials in pancreatic cancer.

Cytokines as Biomarkers of Pancreatic Ductal Adenocarcinoma: A Systematic Review

OBJECTIVES

A systematic review of the role of cytokines in clinical medicine as diagnostic, prognostic, or predictive biomarkers in pancreatic ductal adenocarcinoma was undertaken.

MATERIALS AND METHODS

A systematic review was conducted according to the 2009 PRISMA guidelines. PubMed database was searched for all original articles on the topic of interest published until June 2015, and this was supplemented with references cited in relevant articles. Studies were evaluated for risk of bias using the Quality in Prognosis Studies tools.

RESULTS

Forty one cytokines were investigated with relation to pancreatic ductal adenocarcinoma (PDAC) in 65 studies, ten of which were analyzed by more than three studies. Six cytokines (interleukin[IL]-1β, -6, -8, -10, vascular endothelial growth factor, and transforming growth factor) were consistently reported to be increased in PDAC by more than four studies; irrespective of sample type; method of measurement; or statistical analysis model used. When evaluated as part of distinct panels that included CA19-9, IL-1β, -6 and -8 improved the performance of CA19-9 alone in differentiating PDAC from healthy controls. For example, a panel comprising IL-1β, IL-8, and CA 19-9 had a sensitivity of 94.1% vs 85.9%, specificity of 100% vs 96.3%, and area under the curve of 0.984 vs 0.925. The above-mentioned cytokines were associated with the severity of PDAC. IL-2, -6, -10, VEGF, and TGF levels were reported to be altered after patients received therapy or surgery. However, studies did not show any evidence of their ability to predict treatment response.

CONCLUSION

Our review demonstrates that there is insufficient evidence to support the role of individual cytokines as diagnostic, predictive or prognostic biomarkers for PDAC. However, emerging evidence indicates that a panel of cytokines may be a better tool for discriminating PDAC from other non-malignant pancreatic diseases or healthy individuals.

Critical role of oncogenic KRAS in pancreatic cancer (Review)

Pancreatic cancer is a human malignancy with one of the highest mortality rates and little progress has been achieved in its treatment in recent decades. Further improvement to the understanding of the biological and molecular mechanisms underlying the initiation and development of pancreatic ductal adenocarcinoma (PDAC) is required. Previous studies using genetically engineered mouse models have demonstrated that oncogenic GTPase KRas (KRAS) mutation is involved in the formation of pancreatic intraepithelial neoplasia and promotes the progression of PDAC. However, attempts to target KRAS directly by pharmacological inhibition have been unsuccessful. This has resulted in increased efforts to identify pharmacological targets and nodes associated with the mutated KRAS. The present review discusses the recent progress and prospects of KRAS signaling in pancreatic cancer.

Tumor-associated Neutrophils and Malignant Progression in Intraductal Papillary Mucinous Neoplasms: An Opportunity for Identification of High-risk Disease

OBJECTIVES

To evaluate the association of tumor-associated neutrophils (TANs) with malignant progression in intraductal papillary mucinous neoplasms (IPMNs) and to study the cyst fluid from these lesions for biomarkers of the inflammation-carcinogenesis association.

BACKGROUND

There is a strong link between TANs and malignant progression. Inflammatory mediators released by these cells may be a measurable surrogate marker of this progression.

METHODS

We evaluated 78 resected IPMNs (2004-2013). Lesions were divided into the low-risk (low- and intermediate-grade dysplasia: n = 48) and high-risk (high-grade dysplasia and invasive carcinoma: n = 30) groups. TANs were assessed and categorized (negative, low, and high). A multiplexed assay was performed to evaluate 87 different cyst fluid proteins, including cyst fluid inflammatory markers (CFIMs), as possible surrogate markers for parenchymal inflammation.

RESULTS

Significant positive correlation between grade of dysplasia and TANs was found. High levels of TANs were identified in 2%, 33%, and 89% of the lesions when stratified by grade of dysplasia into low/intermediate-grade dysplasia, high-grade dysplasia, and invasive carcinoma, respectively (P < 0.001). Higher grades of dysplasia were also found to have positive correlation with 29 of the measured proteins, of which 23 (79%) were CFIMs. Higher levels of TANs correlated with higher levels of 18 CFIMs, of which 16 (89%) were also found to be associated with higher grades of dysplasia.

CONCLUSIONS

In this study, TANs were strongly associated with malignant progression in IPMNs. Measurement of CFIMs may be a surrogate marker for IPMN progression and allow for the identification of high-risk disease.

Pancreatic cancer, treatment options, and GI-4000

Although pancreatic cancer is but the eleventh most prevalent cancer in the US, it is predicted that of all the patients newly diagnosed with this disease in 2014, only 27% will still be alive at the end of the first year, which is reduced to 6% after 5 years. The choice of chemotherapy in the treatment of pancreatic cancer is dependent on disease stage and patient performance status but, in general, the most widely used approved regimens include 5-fluorouracil (5-FU) combinations and gemcitabine combinations. Recent therapeutic strategies have resulted in an improvement in survival of patients with pancreatic cancer but the magnitude of change is disappointing and vast improvements are still needed. The goal of immunotherapy is to enhance and guide the body's immune system to recognize tumor-specific antigens and mount an attack against the disease. Among newer immune therapies, GI-4000 consists of 4 different targeted molecular immunogens, each containing a different Ras protein (antigen) encoded by the most commonly found mutant RAS genes in solid tumors-RAS mutations exist in over 90% of pancreatic ductal adenocarcinomas. We will review pancreatic cancer epidemiology and its current treatment options, and consider the prospects of immunotherapy, focusing on GI-4000. We discuss the potential mechanism of action of GI-4000, and the performance of this vaccination series thus far in early phase clinical trials.

Activation of Toll-like receptor 7 regulates the expression of IFN-λ1, p53, PTEN, VEGF, TIMP-1 and MMP-9 in pancreatic cancer cells

Toll-like receptors (TLRs) are critical in the induction of the immune response in tumor development. TLR7 has previously been demonstrated to be associated with the development of pancreatic cancer, and the release of cytokines and chemokines from other types of cancer cell; however, the specific expression induced by TLR7 agonists in pancreatic cancer cells remains to be elucidated. The present study aimed to investigate the effects of the TLR7 agonist, gardiquimod, on ERK1/2 signaling pathway, and on the expression of genes involved in the pathogenesis of cancer, including phosphatase and tensin homolog deleted on chromosome 10 (PTEN), p53, type Ⅲ interferon (IFN-λ1), vascular endothelial growth factor (VEGF), matrix metalloproteinase 9 (MMP-9) and tissue inhibitor of metalloproteinase 1 (TIMP-1). The results demonstrated that activation of TLR7 upregulated the expression levels of certain genes to varying degrees; the expression levels of IFN-λ1 and MMP-9 were increased by ~3 fold, whereas other genes (p53, PTEN, TIMP-1) were upregulated by ~2 fold, and VEGF was marginally upregulated after 10 min. Furthermore, gardiquimod increased the expression levels of phosphorylated-extracellular signal-regulated kinase (ERK)1/2. In addition, PD98059, a specific inhibitor of ERK phosphorylation, inhibited the ability of gardiquimod to activate ERK1/2; consequently weakening the effect of gardiquimod on gene regulation. These findings indicated that the effect of TLR7 agonists, including gardiquimod, on gene expression in BxPC-3 pancreatic cancer cells was partly associated with the mitogen-activated protein kinase-ERK1/2 signaling pathway.

Diagnostic value of selected markers and apoptotic pathways for pancreatic cancer

Pancreatic cancer occupies the fourth place as a cause of death from cancer, and the mortality rate is similar to the number of newly detected cases. Due to the late diagnosis, only 5-6% of patients with pancreatic cancer survive for five years. Given that early diagnosis is critical for improving patients' survival rates, there is an urgent need for the discovery and validation of new biomarkers with sufficient sensitivity and specificity to help diagnose pancreatic cancer early. Detection of serum tumor markers (CA19-9, CEA, CA125 and CA242) is conducive to the early diagnosis of pancreatic cancer. The combination of miR-16, miR-196a and CA19-9 plasma level was more effective, especially in early tumor screening. Furthermore, recent studies reported that mainly miR-21, miR-155 and miR-196 were dysregulated in IPMN (intraductal papillary mucinous neoplasms) and PanIN (pancreatic intraepithelial neoplasia) lesions, suggesting their usefulness as early biomarkers of these diseases. The reduced rate of apoptosis plays a crucial role in carcinogenesis, and it is one of the most important characteristics acquired by pancreatic cancer cells, which protects them from attack by the immune system and reduces the effectiveness of pharmacological treatment. This review summarizes the data concerning the clinical utility of selected biomarkers in pancreatic cancer patients. The review mainly focuses on the genetic aspects of signaling pathway disorders associated with apoptosis in the pathogenesis and diagnosis of pancreatic cancer.

Bidirectional interconversion of stem and non-stem cancer cell populations: A reassessment of theoretical models for tumor heterogeneity

Resolving the origin of intratumor heterogeneity has proven to be one of the central challenges in cancer research during recent years. Two theoretical models explaining the emergence of intratumor heterogeneity have come to dominate cancer biology literature: the clonal evolution model and the hierarchical/cancer stem cell model. Recently, a plastic model that combines elements of both the clonal and the hierarchical model has gained traction. Basically, this model proposes that cancer stem cells engage in bidirectional interconversion with non-stem cells, thereby providing the missing link between the 2 conventional models. Confirming bidirectional interconversion as a hallmark of cancer is a crucial step in understanding tumor heterogeneity and has important therapeutic implications. In this review, current methodologies and theoretical and empirical evidence regarding bidirectional interconversion will be discussed.

Selective inhibition of the p38 alternative activation pathway in infiltrating T cells inhibits pancreatic cancer progression. Nat Med. 2015;21:1337-1343. [PMID: 26479921 PMCID: PMC4636461 DOI: 10.1038/nm.3957]

Pancreatic ductal adenocarcinoma (PDAC) is a highly aggressive neoplasm characterized by a marked fibro-inflammatory microenvironment¹, the presence of which can promote both cancer induction and growth^2–4. Therefore, selective manipulation of local cytokines is an attractive if unrealized therapeutic approach. T cells possess a unique mechanism of activation of p38 MAPK downstream of T cell receptor (TCR) engagement by phosphorylation of Tyr-323 (pY323). This alternative p38 activation pathway is required for pro-inflammatory cytokine production^5,6. Here we show in human PDAC that a high percentage of infiltrating pY323⁺ T cells was associated with large numbers of TNFα and IL-17-producing CD4⁺ tumor-infiltrating lymphocytes (TIL) and aggressive disease. The growth of murine pancreatic tumors was inhibited by genetic ablation of the alternative p38 pathway, and transfer of wild type CD4⁺ T cells but not those lacking the alternative pathway enhanced tumor growth in T cell-deficient mice. Strikingly, a plasma membrane-permeable peptide derived from Gadd45α, the naturally-occurring inhibitor of p38 pY323⁺ (ref. 7), reduced CD4⁺ TIL production of TNFα, IL-17A, IL-10, and secondary cytokines, halted growth of implanted tumors, and inhibited progression of spontaneous K-ras-driven adenocarcinoma in mice. Thus, TCR-mediated activation of CD4⁺ TIL results in alternative p38 activation and production of pro-tumorigenic factors, and can be targeted for therapeutic benefit.

Activation of Toll-like receptor 7 inhibits the proliferation and migration, and induces the apoptosis of pancreatic cancer cells

Pancreatic cancer is one of the most malignant types of tumor and has a poor prognosis. Toll‑like receptor 7 (TLR7) has been found to be present and have different roles in different types of cancer cells. In the present study, the roles of TLR7 in BxPC‑3 cells, a human pancreatic adenocarcinoma cell line, were investigated. The cells were treated with gardiquimod, an agonist of TLR7, following which the properties of the cells, including proliferation, migration, cell cycle and apoptosis, were analyzed. It was revealed that activation of TLR7 by gardiquimod inhibited cell proliferation and migration, and induced apoptosis of the cells. In addition, gardiquimod downregulated the expression levels of cyclin B1, cyclin E and B‑cell lymphoma 2, while upregulating the expression of B‑cell‑associated X protein. These results suggested that the activation of TLR7 suppresses the progression of pancreatic cancer.

Pancreatic cancer: optimizing treatment options, new, and emerging targeted therapies

Pancreatic cancer is the fourth leading cause of cancer death in the US and is expected to become the second leading cause of cancer-related deaths in the next decade. Despite 5-fluorouracil/leucovorin with irinotecan and oxaliplatin (FOLFIRINOX) and gemcitabine/nab-paclitaxel significantly improving outcomes for metastatic cancer, refractory disease still poses significant challenges. Difficulties with early detection and the inherent chemo- and radio-resistant nature of this malignancy led to attempts to define the sequential biology of pancreatic cancer in order to improve survival outcomes. Pancreatic adenocarcinoma is characterized by several germline or acquired genetic mutations, the most common being KRAS (90%), CDK2NA (90%), TP53 (75%-90%), DPC4/SMAD4 (50%). In addition, the tumor microenvironment, chemoresistant cancer stem cells, and the desmoplastic stroma have been the target of some promising clinical investigations. Among the core pathways reproducibly shown to lead the development and progression of this disease, DNA repair, apoptosis, G1/S cell cycle transition, KRAS, Wnt, Notch, Hedgehog, TGF-beta, and other cell invasion pathways, have been the target of "precision therapeutics". No single molecularly targeted therapeutic though has been uniformly successful, probably due to the tumor heterogeneity, but biomarker research is evolving and it hopes to select more patients likely to benefit. Recent reports note activity with immunotherapies such as CD40 agonists, CCR2 inhibitors, cancer vaccines, and novel combinations against the immunosuppressive tumor milieu are ongoing. While many obstacles still exist, clearly we are making progress in deciphering the heterogeneity within pancreatic cancers. Integrating conventional and immunological targeting will be the key to effective treatment of this deadly disease.

Imaging and Therapy of Pancreatic Cancer with Phosphatidylserine-Targeted Nanovesicles

Pancreatic cancer remains one of the most intractable cancers, with a dismal prognosis reflected by a 5-year survival of ~6%. Since early disease symptoms are undefined and specific biomarkers are lacking, about 80% of patients present with advanced, inoperable tumors that represent a daunting challenge. Despite many clinical trials, no single chemotherapy agent has been reliably associated with objective response rates above 10% or median survival longer than 5 to 7 months. Although combination chemotherapy regimens have in recent years provided some improvement, overall survival (8-11 months) remains very poor. There is therefore a critical need for novel therapies that can improve outcomes for pancreatic cancer patients. Here, we present a summary of the current therapies used in the management of advanced pancreatic cancer and review novel therapeutic strategies that target tumor biomarkers. We also describe our recent research using phosphatidylserine-targeted saposin C-coupled dioleoylphosphatidylserine nanovesicles for imaging and therapy of pancreatic cancer.

Impact of diabetes type II and chronic inflammation on pancreatic cancer

Background

We explored if known risk factors for pancreatic cancer such as type II diabetes and chronic inflammation, influence the pathophysiology of an established primary tumor in the pancreas and if administration of metformin has an impact on tumor growth.

Methods

Pancreatic carcinomas were assessed in a syngeneic orthotopic pancreas adenocarcinoma model after injection of 6606PDA cells in the pancreas head of either B6.V-Lep^ob/ob mice exhibiting a type II diabetes-like syndrome or normoglycemic mice. Chronic pancreatitis was then induced by repetitive administration of cerulein. Cell proliferation, cell death, inflammation and the expression of cancer stem cell markers within the carcinomas was evaluated by immunohistochemistry. In addition, the impact of the antidiabetic drug, metformin, on the pathophysiology of the tumor was assessed.

Results

Diabetic mice developed pancreatic ductal adenocarcinomas with significantly increased tumor weight when compared to normoglycemic littermates. Diabetes caused increased proliferation of cancer cells, but did not inhibit cancer cell necrosis or apoptosis. Diabetes also reduced the number of Aldh1 expressing cancer cells and moderately decreased the number of tumor infiltrating chloracetate esterase positive granulocytes. The administration of metformin reduced tumor weight as well as cancer cell proliferation. Chronic pancreatitis significantly diminished the pancreas weight and increased lipase activity in the blood, but only moderately increased tumor weight.

Conclusion

We conclude that diabetes type II has a fundamental influence on pancreatic ductal adenocarcinoma by stimulating cancer cell proliferation, while metformin inhibits cancer cell proliferation. Chronic inflammation had only a minor effect on the pathophysiology of an established adenocarcinoma.

SIBLINGs and SPARC families: Their emerging roles in pancreatic cancer

Pancreatic cancer has a considerably poor prognosis with a 5-year survival probability of less than 5% when all stages are combined. Pancreatic cancer is characterized by its dense stroma, which is involved in the critical interplay with the tumor cells throughout tumor progression and furthermore, creates a barrier restricting efficient penetration of therapeutics. Alterations in a large number of genes are reflected by a limited number of signaling pathways, which are potential targets. Understanding more about the molecular basis of this devastating cancer type regarding tumor microenvironment, distinct subpopulations of cells, epithelial-to-mesenchymal transition and inflammation will lead to the development of various targeted therapies for controlling tumor growth and metastasis. In this complex scenario of pancreatic cancer, especially members of the “small integrin binding ligand N-linked glycoproteins” (SIBLINGs) and “secreted protein acidic and rich in cysteine” (SPARC) families have emerged due to their prominent roles in properties including proliferation, differentiation, apoptosis, adhesion, migration, angiogenesis, wound repair and regulation of extracellular matrix remodeling. SIBLINGs consist of five members, which include osteopontin (OPN), bone sialoprotein, dentin matrix protein 1, dentin sialophosphoprotein and matrix extracellular phosphoglycoprotein. The SPARC family of modular extracellular proteins is comprised of SPARC/osteonectin (ON) and SPARC-like 1 (hevin); secreted modular calcium binding proteins; testicans and follistatin-like protein. In this review, we especially focus on OPN and ON, elaborating on their special and growing importance in pancreatic cancer diagnosis and prognosis.