Statin use and risk of pancreatic cancer: results from a large, clinic-based case-control study

A proteomic signature and potential pharmacological opportunities in the adaptive resistance to MEK and PI3K kinase inhibition in pancreatic cancer cells

Pancreatic cancer is one of the most lethal cancer types and is becoming a leading cause of cancer-related deaths. The limited benefit offered by chemotherapy agents has propelled the search for alternative approaches that target specific molecular drivers of cancer growth and progression. Mutant KRas and effector pathways Raf/MEK/ERK and PI3K/Akt are key players in pancreatic cancer; however, preclinical studies have shown adaptive tumour response to combined MEK and PI3K kinase inhibition leading to treatment resistance. There is a critical unmet need to decipher the molecular basis underlying adaptation to this targeted approach. Here, we aimed to identify common protein expression alterations associated with adaptive resistance in KRas-mutant pancreatic cancer cells, and test if it can be overcome by selected already available small molecule drugs. We found a group of 14 proteins with common expression change in resistant cells, including KRas, caveolin-1, filamin-a, eplin, IGF2R and cytokeratins CK-8, -18 and -19. Notably, several proteins have previously been observed in pancreatic cancer cells with intrinsic resistance to the combined kinase inhibition treatment, suggesting a proteomic signature. We also found that resistant cells are sensitive to small molecule drugs ERK inhibitor GDC-0994, S6K1 inhibitor DG2 and statins.

Deciphering epithelial-to-mesenchymal transition in pancreatic cancer

Epithelial to mesenchymal transition (EMT) is a complex cellular program that alters epithelial cells and induces their transformation into mesenchymal cells. While essential to normal developmental processes such as embryogenesis and wound healing, EMT has also been linked to the development and progression of various diseases, including fibrogenesis and tumorigenesis. Under homeostatic conditions, initiation of EMT is mediated by key signaling pathways and pro-EMT-transcription factors (EMT-TFs); however, in certain contexts, these pro-EMT regulators and programs also drive cell plasticity and cell stemness to promote oncogenesis as well as metastasis. In this review, we will explain how EMT and EMT-TFs mediate the initiation of pro-cancer states and how they influence late-stage progression and metastasis in pancreatic ductal adenocarcinoma (PDAC), the most severe form of pancreatic cancer.

Mutant p53 driven-LINC00857, a protein scaffold between FOXM1 and deubiquitinase OTUB1, promotes the metastasis of pancreatic cancer

Tumour metastasis is the major adverse factor for recurrence and death in pancreatic cancer (PC) patients. P53 mutations are considered to be the second most common type of mutation in PC and significantly promote PC metastasis. However, the molecular mechanisms underlying the effects of p53 mutations, especially the regulatory relationship of the protein with long noncoding RNAs (lncRNAs), remain unclear. In the present study, we demonstrated that the lncRNA LINC00857 exhibits a significantly elevated level in PC and that it is associated with poor prognosis; furthermore, TCGA data showed that LINC00857 expression was significantly upregulated in the mutant p53 group compared with the wild-type p53 group. Gain- and loss-of-function experiments showed that LINC00857 promotes the metastasis of PC cells. We further found that LINC00857 upregulates FOXM1 protein expression and thus accelerates metastasis in vitro and in vivo. Mechanistically, LINC00857 bound simultaneously to FOXM1 and to the deubiquitinase OTUB1, thereby serving as a protein scaffold and enhancing the interaction between FOXM1 and OTUB1, which inhibits FOXM1 degradation through the ubiquitin-proteasome pathway. Interestingly, we found that mutant p53 promotes LINC00857 transcription by binding to its promoter region. Finally, atorvastatin, a commonly prescribe lipid-lowering drug, appeared to inhibit PC metastasis by inhibiting the mutant p53-LINC00857 axis. Taken together, our results provide new insights into the biology driving PC metastasis and indicate that the mutant p53-LINC00857 axis might represent a novel therapeutic target for PC metastasis.

Interplay Between Fatty Acids, Stearoyl-Co-A Desaturase, Mechanistic Target of Rapamycin, and Yes-Associated Protein/Transcriptional Coactivator With PDZ-Binding Motif in Promoting Hepatocellular Carcinoma

Nonalcoholic fatty liver disease has reached pandemic proportions with one of its most consequential complications being hepatocellular carcinoma (HCC). Nonalcoholic fatty liver disease-related HCC is becoming the leading indication for liver transplantation in the United States. Given the scarcity of available organs, early detection and prevention remain key in prevention and management of the disease. Over the years, the yes-associated protein (YAP)/transcriptional coactivator with PDZ-binding motif (TAZ) pathway emerged as a key signal transduction pathway in the pathogenesis of HCC. In this review, we explore the interplay between the YAP/TAZ pathway as a point of convergence in HCC pathogenesis. We review the evidence of how lipid reprogramming and key lipid pathways, saturated and monounsaturated fatty acids (through the rate-limiting enzyme stearoyl Co-A desaturase), the mevalonic acid pathway (the role of statins), and mechanistic target of rapamycin all play critical roles in intricate and complex networks that tightly regulate the YAP/TAZ pro-oncogenic pathway.

Ezetimibe and Cancer: Is There a Connection?

The high level of serum cholesterol caused by the excessive absorption of cholesterol can lead to hypercholesteremia, thus promoting the occurrence and development of cancer. Ezetimibe is a drug that reduces cholesterol absorption and has been widely used for the treatment of patients with high circulating cholesterol levels for many years. Mechanistically, ezetimibe works by binding to NPC1L1, which is a key mediator of cholesterol absorption. Accumulating data from preclinical models have shown that ezetimibe alone could inhibit the development and progression of cancer through a variety of mechanisms, including anti-angiogenesis, stem cell suppression, anti-inflammation, immune enhancement and anti-proliferation. In the past decade, there has been heated discussion on whether ezetimibe combined with statins will increase the risk of cancer. At present, more and more evidence shows that ezetimibe does not increase the risk of cancers, which supports the role of ezetimibe in anti-cancer. In this review, we discussed the latest progress in the anti-cancer properties of ezetimibe and elucidated its underlying molecular mechanisms. Finally, we highlighted the potential of ezetimibe as a therapeutic agent in future cancer treatment and prevention.

An Update on Common Pharmaceuticals in the Prevention of Pancreatic Cancer

In this review, we aim to update readers about the most recent studies on common pharmaceuticals and their association with pancreatic cancer risk. The use of prophylactic aspirin, metformin, beta-blockers, and statins has been studied in the past but showed inconclusive results in the reduction of pancreatic cancer incidence. However, in recent studies, these medications along with combination therapy of aspirin and metformin were found to have a more significant association with decreasing risk. Given the poor prognosis of pancreatic cancer despite treatment, medication prophylaxis prevention should be considered. In this review, we hope to encourage future case-control or prospective studies on common medications that have shown great potential in delaying pancreatic cancer development.

Statins and the risk of pancreatic cancer: A systematic review and meta-analysis of 2,797,186 patients

BACKGROUND

Statin use in many studies is related to the improvement of a patients' condition including reducing the risk of various malignancies. Herein, is a systematic review and meta-analysis to examine the evidence on the association between statin therapy and the risk of the occurrence of pancreatic cancer, mainly in terms of decreased risk of developing pancreatic cancer among patients using statin therapy in the long-term perspective.

METHODS

PubMed, Web of Science, Scopus and Cochrane Central Register of Controlled Trials (CENTRAL) were searched from database inception to December 1st, 2021. Random effect models were used to estimate summary odds ratios (OR) and the corresponding 95% confidence intervals (CI).

RESULTS

A total of 26 studies comprising 2,797,186 patients were included. Polled analysis showed that pancreatic cancer occurrence in statin vs. no-statin group varied and amounted to 0.4% vs. 0.6% (RR = 0.83; 95% CI: 0.72-0.96; I² = 84%; p = 0.01).

CONCLUSIONS

In summary, the present analysis shows that overall statins use is significantly associated with a reduction in risk of pancreatic cancer. However, these results were not confirmed for the randomized controlled trial subgroup. Further prospective studies are needed to confirm the current results.

Statin as a therapeutic agent in gastroenterological cancer

Statins inhibit 3-hydroxy-3-methylglutaryl-CoA reductase, the rate-limiting enzyme of the mevalonate pathway, and are widely used as an effective and safe approach handle hypercholesterolemia. The mevalonate pathway is a vital metabolic pathway that uses acetyl-CoA to generate isoprenoids and sterols that are crucial to tumor growth and progression. Multiple studies have indicated that statins improve patient prognosis in various carcinomas. Basic research on the mechanisms underlying the antitumor effects of statins is underway. The development of new anti-cancer drugs is progressing, but increasing medical costs from drug development have become a major obstacle. Readily available, inexpensive and well-tolerated drugs like statins have not yet been successfully repurposed for cancer treatment. Identifying the cancer patients that may benefit from statins is key to improved patient treatment. This review summarizes recent advances in statin research in cancer and suggests important considerations for the clinical use of statins to improve outcomes for cancer patients.

Statins Inhibit Inflammatory Cytokine Production by Macrophages and Acinar-to-Ductal Metaplasia of Pancreatic Cells

BACKGROUND AND AIMS:

Animal data show that the presence of an oncogenic Kras mutation in pancreatic acinar cells leads to acinar-to-ductal metaplasia (ADM), pancreatic intraepithelial neoplasia (PanIN), and pancreatic ductal adenocarcinoma (PDAC). Inflammatory macrophages play an important role in the formation of ADMs and transition to PanINs. Epidemiologically, statins are associated with a reduced risk of PDAC. We investigated whether statins inhibit inflammatory cytokine production in macrophages and whether this leads to reduced ADM formation.

METHODS:

The efficacy of statins on inflammatory cytokine production in 2 macrophage cell lines was measured by real-time polymerase chain reaction and enzyme-linked immunosorbent assay. The effect of macrophage-conditioned medium on ADM in primary pancreatic acinar cells was investigated. Mouse pancreatic tissue samples were analyzed for macrophage numbers, cytokine levels, and neoplastic/dysplastic area.

RESULTS:

Lipophilic statins prevented inflammatory cytokine production in Raw264.7 and J774A.1 cells stimulated by lipopolysaccharide. The inhibitory effect of statins was mediated by inhibition of mevalonate and geranylgeranyl pyrophosphate synthesis and disruption of the actin cytoskeleton but not by a reduction in intracellular cholesterol. Treatment of macrophages with lipophilic statins also blocked ADM formation of primary pancreatic acinar cells. Furthermore, oral administration of simvastatin was associated with a reduction in the number of intrapancreatic macrophages, decreased inflammatory cytokine levels in the pancreas, and attenuated ADM/PanIN formation in mice.

CONCLUSION:

Our data support the hypothesis that statins oppose early PDAC development by their effects on macrophages and ADM formation. The inhibitory actions of statins on macrophages may collaborate with direct inhibitory effects on transformed pancreatic epithelial cells, which cumulatively may reduce early PDAC development and progression.

Statins affect cancer cell plasticity with distinct consequences for tumor progression and metastasis

Statins are among the most commonly prescribed drugs, and around every fourth person above the age of 40 is on statin medication. Therefore, it is of utmost clinical importance to understand the effect of statins on cancer cell plasticity and its consequences to not only patients with cancer but also patients who are on statins. Here, we find that statins induce a partial epithelial-to-mesenchymal transition (EMT) phenotype in cancer cells of solid tumors. Using a comprehensive STRING network analysis of transcriptome, proteome, and phosphoproteome data combined with multiple mechanistic in vitro and functional in vivo analyses, we demonstrate that statins reduce cellular plasticity by enforcing a mesenchymal-like cell state that increases metastatic seeding ability on one side but reduces the formation of (secondary) tumors on the other due to heterogeneous treatment responses. Taken together, we provide a thorough mechanistic overview of the consequences of statin use for each step of cancer development, progression, and metastasis.

Context Matters-Why We Need to Change From a One Size Fits all Approach to Made-to-Measure Therapies for Individual Patients With Pancreatic Cancer

Pancreatic cancer is one of the deadliest cancers and remains a major unsolved health problem. While pancreatic ductal adenocarcinoma (PDAC) is associated with driver mutations in only four major genes (KRAS, TP53, SMAD4, and CDKN2A), every tumor differs in its molecular landscape, histology, and prognosis. It is crucial to understand and consider these differences to be able to tailor treatment regimens specific to the vulnerabilities of the individual tumor to enhance patient outcome. This review focuses on the heterogeneity of pancreatic tumor cells and how in addition to genetic alterations, the subsequent dysregulation of multiple signaling cascades at various levels, epigenetic and metabolic factors contribute to the oncogenesis of PDAC and compensate for each other in driving cancer progression if one is tackled by a therapeutic approach. This implicates that besides the need for new combinatorial therapies for PDAC, a personalized approach for treating this highly complex cancer is required. A strategy that combines both a target-based and phenotypic approach to identify an effective treatment, like Reverse Clinical Engineering® using patient-derived organoids, is discussed as a promising way forward in the field of personalized medicine to tackle this deadly disease.

Biological Significance of YAP/TAZ in Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) remains one of the most lethal types of cancer. Despite major advances in defining the molecular mutations driving PDAC, this disease remains universally lethal with an overall 5-year survival rate of only about 7–8%. Genetic alterations in PDAC are exemplified by four critical genes (KRAS, TP53, CDKN2A, and SMAD4) that are frequently mutated. Among these, KRAS mutation ranges from 88% to 100% in several studies. Hippo signaling is an evolutionarily conserved network that plays a key role in normal organ development and tissue regeneration. Its core consists of the serine/threonine kinases mammalian sterile 20-like kinase 1 and 2 (MST1/2) and large tumor suppressor 1 and 2. Interestingly, pancreas-specific MST1/2 double knockout mice have been reported to display a decreased pancreas mass. Many of the genes involved in the Hippo signaling pathway are recognized as tumor suppressors, while the Hippo transducers Yes-associated protein (YAP) and transcriptional co-activator with PDZ-binding motif (TAZ) are identified as oncogenes. By dephosphorylation, YAP and TAZ accumulate in the nucleus and interact with transcription factors such as TEA domain transcription factor-1, 2, 3, and 4. Dysregulation of Hippo signaling and activation of YAP/TAZ have been recognized in a variety of human solid cancers, including PDAC. Recent studies have elucidated that YAP/TAZ play a crucial role in the induction of acinar-to-ductal metaplasia, an initial step in the progression to PDAC, in genetically engineered mouse models. YAP and TAZ also play a key role in the development of PDAC by both KRAS-dependent and KRAS-independent bypass mechanisms. YAP/TAZ have become extensively studied in PDAC and their biological importance during the development and progression of PDAC has been uncovered. In this review, we summarize the biological significance of a dysregulated Hippo signaling pathway or activated YAP/TAZ in PDAC and propose a role for YAP/TAZ as a therapeutic target.

Statin Exposure and Pancreatic Cancer Incidence: A Japanese Regional Population-Based Cohort Study, the Shizuoka Study

Preclinical studies suggest that statins contribute to the prevention of pancreatic cancer; however, the results of epidemiologic studies are inconsistent. Furthermore, sufficient data are unavailable for the general population of Asia. Here, we conducted an observational study using a comprehensive patient-linked, longitudinal health insurance database comprising the records of 2,230,848 individuals residing in Shizuoka Prefecture, Japan, from April 2012 to September 2018. We included individuals older than 40 years with data for medical examinations and statin exposure (≥365 statin prescription days). To balance baseline characteristics between the statin exposure and statin nonexposure groups, we used inverse probability of treatment propensity score weighting method. We estimated hazard ratios for associations with pancreatic cancer using the Cox proportional hazards regression model. Among 2,230,848 individuals, we included 100,537 in the statin exposure group (24%) and 326,033 in the statin nonexposure group (76%). Among the statin exposure group (352,485 person-years) and the statin nonexposure group (1,098,463 person-years), 394 (1.12 per 1,000 person-years) and 1176 (1.07 per 1,000 person-years) developed pancreatic cancer, respectively (P = 0.464). After adjustments using inverse probability of treatment weighting, the statin exposure group was associated with a decreased incidence of pancreatic cancer (hazard ratio, 0.84; 95% confidence intervals, 0.72-0.99; P = 0.036). In conclusion, the current Japanese regional population-based cohort study shows that statin exposure was associated with a lower incidence of pancreatic cancer. PREVENTION RELEVANCE: This study may support the possible role of statins in preventing pancreatic cancer in the general population in Japan.

Anti-tumor effect of statin on pancreatic adenocarcinoma: From concept to precision medicine

A statin is a cholesterol-lowering agent, which inhibits HMG-CoA (3-hydroxy-3-methylglutaryl-coenzyme A) reductase and subsequently reduces the cholesterol precursor, and was first used commercially in 1987. The concept of cholesterol restriction leading to cancer cell dysfunction was proposed in 1992. The interruption of different signaling pathways has been proved in preclinical experiments to elucidate the anti-tumor mechanism of statins in pancreatic adenocarcinoma. Observational studies have shown that the clinical use of statins is beneficial in patients with pancreatic adenocarcinoma, including a chemoprevention effect, post-surgical resection follow-up and therapeutic prognosis of advanced cancer stage. Arrest of the cancer cell cycle by the combined use of gemcitabine and statin was observed in a cell line study. The effect of microbiota on the tumor microenvironment of pancreatic adenocarcinoma is a new therapeutic approach as statins can modulate the gut microbiota. Hence, further randomized trials of statins in pancreatic adenocarcinoma treatment will be warranted with application of precision medicine from microbiota-derived, cell cycle-based and signaling pathway-targeted research.

Influence of cholesterol on cancer progression and therapy

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Abnormality in blood cholesterol level is significantly correlated with risk of different cancers.

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Majority of tumor tissue from cancer patient exhibits overexpression of LDLR and ACAT for supporting rapid cancer cell proliferation.

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Alteration of the cholesterol metabolism in cancer cells hampers therapeutic response.

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Targeting cholesterol metabolism for treatment of cancer with other conventional chemotherapeutic drugs appears to be beneficial.

Cholesterol is a fundamental molecule necessary for the maintenance of cell structure and is vital to various normal biological functions. It is a key factor in lifestyle-related diseases including obesity, diabetes, cardiovascular disease, and cancer. Owing to its altered serum chemistry status under pathological states, it is now being investigated to unravel the mechanism by which it triggers various health complications. Numerous clinical studies in cancer patients indicate an alteration in blood cholesterol level (either decreased or increased) in comparison to normal healthy individuals. This article elaborates on our understanding as to how cholesterol is being hijacked in the malignancy for the development, survival, stemness, progression, and metastasis of cancerous cells. Also, it provides a glimpse of how cholesterol derived entities, alters the signaling pathway towards their advantage. Moreover, deregulation of the cholesterol metabolism pathway has been often reported to hamper various treatment strategies in different cancer. In this context, attempts have been made to bring forth its relevance in being targeted, in pre-clinical and clinical studies for various treatment modalities. Thus, understanding the role of cholesterol and deciphering associated molecular mechanisms in cancer progression and therapy are of relevance towards improvement in the management of various cancers.

Association Between Statin Use, Intensity and Acute Liver Injury in Human Immunodeficiency Virus, Hepatitis C Virus, and Uninfected US Veterans

OBJECTIVE

We sought to evaluate the relationship between acute liver injury (ALI) and statins utilizing the Veterans Affairs Informatics and Computing Infrastructure (VINCI) database.

METHODS

This retrospective cohort study, spanning January 2000-December 2018, compared ALI (aminotransferase > 200 U/L, severe ALI, and hospitalization with ALI) in statin users and non-users among uninfected, hepatitis C virus (HCV) mono-infected, human immunodeficiency virus (HIV)/HCV co-infected, and HIV mono-infected veterans within 18 months. We estimated adjusted Cox proportional hazards models comparing statin users and non-users and comparing statin intensity level with non-use; and estimate Cox proportional hazards models utilizing time-dependent coding of statin intensity. Adjusted models included restricted cubic splines of the propensity score as an adjustment variable.

RESULTS

From a total of 166,439 patients who met the study criteria, statin initiators were older, had higher values of body mass index, higher values of low-density lipoprotein cholesterol and triglycerides, and lower values of high-density lipoprotein cholesterol. HCV mono-infected and HIV/HCV co-infected cohorts had the highest rates of ALI, and statin users had lower rates across all outcomes of ALI compared with non-users in unadjusted analysis. Statin use is associated with a lower risk of all ALI outcomes compared with non-users. Patients on a high intensity are not associated with a statistically significant increase in risk for any ALI outcome. For each additional 30 days of treatment, there was a reduced risk of any ALI outcome across all cohorts.

CONCLUSIONS

Statin initiators had a lower risk of any ALI outcome compared with non-users within 18 months regardless of HIV and/or HCV status.

Transcriptome sequencing analysis reveals unique and shared antitumor effects of three statins in pancreatic cancer

Statins, a class of commonly prescribed cholesterol‑lowering medications, have been revealed to influence the risk of multiple types of cancer. However, the antitumor effects of statins on pancreatic cancer and their differential efficacy among a variety of statins are not currently well‑defined. The aim of the present study was therefore to identify and compare the genes and related biological pathways that were affected by each individual statin on pancreatic cancer. Two human pancreatic cancer cell lines, MiaPaCa2 and PANC1, were exposed to three statins, lovastatin, fluvastatin and simvastatin. The inhibitory effect of statins on pancreatic cancer cell proliferation was first validated. Next, RNA‑seq analysis was used to determine the gene expression alterations in either low (2 µM) or high (20 µM) statin concentration‑treated cancer cells. Marked differences in gene transcription profiles of both pancreatic cancer cell lines exposed to high concentration statins were observed. Notably, the high concentration statins significantly suppressed core‑gene CCNA2‑associated cell cycle and DNA replication pathways and upregulated genes involved in ribosome and autophagy pathways. However, the low concentration statin‑induced gene expression alterations were only detected in MiaPaCa2 cells. In conclusion, a marked difference in the intra and inter cell‑type performance of pancreatic cancer cells exposed to a variety of statins at low or high concentrations was reported herein, which may provide insights for the potential clinical use of statins in future pancreatic cancer therapeutics.

Pancreatic Cancer (PDAC): Introduction of Evidence-Based Complementary Measures into Integrative Clinical Management

The most common form of pancreatic cancer is pancreatic ductal adenocarcinoma (PDAC), which comprises some 85% of all cases. Currently, this is the fourth highest cause of cancer mortality worldwide and its incidence is rising steeply. Commonly applied clinical therapies offer limited chance of a lasting cure and the five-year survival rate is one of the lowest of the commonly occurring cancers. This review cultivates the hypothesis that the best management of PDAC would be possible by integrating 'western' clinical medicine with evidence-based complementary measures. Protecting the liver, where PDAC frequently first spreads, is also given some consideration. Overall, the complementary measures are divided into three groups: dietary factors, nutraceutical agents and lifestyle. In turn, dietary factors are considered as general conditioners, multi-factorial foodstuffs and specific compounds. The general conditioners are alkalinity, low-glycemic index and low-cholesterol. The multi-factorial foodstuffs comprise red meat, fish, fruit/vegetables, dairy, honey and coffee. The available evidence for the beneficial effects of the specific dietary and nutraceutical agents was considered at four levels (in order of prominence): clinical trials, meta-analyses, in vivo tests and in vitro studies. Thus, 9 specific agents were identified (6 dietary and 3 nutraceutical) as acceptable for integration with gemcitabine chemotherapy, the first-line treatment for pancreatic cancer. The specific dietary agents were the following: Vitamins A, C, D and E, genistein and curcumin. As nutraceutical compounds, propolis, triptolide and cannabidiol were accepted. The 9 complementary agents were sub-grouped into two with reference to the main 'hallmarks of cancer'. Lifestyle factors covered obesity, diabetes, smoking, alcohol and exercise. An integrative treatment regimen was devised for the management of PDAC patients. This involved combining first-line gemcitabine chemotherapy with the two sub-groups of complementary agents alternately in weekly cycles. The review concludes that integrated management currently offers the best patient outcome. Opportunities to be investigated in the future include emerging modalities, precision medicine, the nerve input to tumors and, importantly, clinical trials.

Investigating disparities: the effect of social environment on pancreatic cancer survival in metastatic patients

Background

Pancreatic adenocarcinoma (PCA) incidence is higher in Black compared to White patients. Beyond race, neighborhood socioeconomic status (nSES) may also inform disparities. However, these effects on metastatic pancreatic adenocarcinoma (mPCA) are not well-studied. The aim of this study was to explore whether nSES influences survival in patients with mPCA.

Methods

nSES measures were derived from U.S. census data at the census tract (CT) level. We correlated medical records of mPCA patients (diagnosed 2010-2016; n=370) to nSES measures retrospectively via a geocode derived from patient address. Multivariable cox proportional hazards models were used to identify patient-level (age, sex, race, marital status, treatment (radiation/chemo/surgery), PCA family history, stage, Jewish ancestry, tobacco use, BMI, diabetes, and statin use) and nSES measures (deprivation, racial concentration, stability, transportation access, immigration) associated with mPCA survival; P values <0.05 were significant.

Results

Eighty-two percent of patients were White; less than one-third of patients resided in highly deprived neighborhoods. Three hundred thirty-three mPCA patient deaths occurred, with a survival ranging from 7-9 months (median 8 months). Patient-level factors including younger age, receipt of chemotherapy or initial surgery and statin use, were associated with improved survival, whereas neighborhood stability (i.e., a higher % of residents still living in the same house as 1 year ago) was significantly associated with poor pancreatic survival.

Conclusions

Our findings suggest nSES has limited effect on survival of mPCA patients as compared to clinical variables. This may be due to the aggressive nature of this cancer, however, additional studies with larger, more diverse cohorts are needed to better understand the effect of nSES on survival of patients with mPCA.

Impact of statin use on cancer-specific mortality and recurrence: A meta-analysis of 60 observational studies

This meta-analysis mainly summarized the studies reporting an association between statin use and cancer-specific mortality and recurrence or progression of cancer patients.We systematically searched for studies about the statin used in cancer patients in electronic databases, including PubMed, Web of Science, Cochrane, Clinical Trials, from inception through the November 2019. A total of 60 studies which included 953,177 participants were eligible with 233,322 cancer patients used statin. Our analysis selected studies presented with outcome based on hazard ratios (HRs) and 95% confidence intervals (CIs) of cancer-specific mortality and cancer recurrence-free survival or progression-free survival. Heterogeneity between the studies was examined using I statistics, and sensitivity analyses were conducted to assess the robustness of the findings. All statistical analyses were performed using RevMan software (version 5.3).The use of statin was potentially associated with a decline in cancer-specific mortality in cancer patients (HR = 0.78; 95% CI: 0.74, 0.84; n = 39; I = 85%). Furthermore, statin use was associated with improved recurrence-free survival (HR = 0.87; 95% CI: 0.78,0.97; n = 23; I = 64%), but not with improvement in progression-free survival (HR = 1.05; 95% CI: 0.95,1.16; n = 14; I2 = 38%).The meta-analysis demonstrated that statin use could exhibit potential survival benefit in the prognosis of cancer patients. But our results are conservative for statins to improve disease recurrence and progression. These findings should be assessed in a prospective randomized cohort.

Mendelian randomisation study of the effects of known and putative risk factors on pancreatic cancer

BACKGROUND

Observational studies have reported multiple risk factors for pancreatic ductal adenocarcinoma (PDAC). Some are well established, like tobacco smoking, alcohol drinking, obesity and type 2 diabetes, whereas some others are putative, such as allergy and dietary factors. Identifying causal risk factors can help establishing those that can be targeted to contribute to prevent PDAC.

OBJECTIVE

We sought to investigate the possible causal effects of established and putative factors on PDAC risk.

METHODS

We conducted a two-sample Mendelian randomisation (MR) study using publicly available data for genetic variants associated with the factors of interest, and summary genetic data from genome-wide association studies of the Pancreatic Cancer Cohort Consortium (PanScan) and the Pancreatic Cancer Case-Control Consortium (PanC4), including in total 8769 cases and 7055 controls. Causality was assessed using inverse-variance weighted, MR-Egger regression and weighted median methods, complemented with sensitivity and radial MR analyses.

RESULTS

We found evidence for a causal effect of body mass index (BMI) on PDAC risk (OR 1.43, 95% CI 1.20 to 1.71, p=8.43×10^-5). Fasting insulin (OR 2.84, 95% CI 1.23 to 6.56, p=0.01), low-density lipoprotein cholesterol (OR 1.16, 95% CI 1.02 to 1.32, p=0.03) and type 2 diabetes (OR 1.09, 95% CI 1.01 to 1.17, p=0.02) were also causally associated with PDAC risk. BMI showed both direct and fasting insulin-mediated causal effects.

CONCLUSION

We found strong evidence that BMI is causally associated with PDAC risk, providing support that obesity management may be a potential prevention strategy for reducing pancreatic cancer risk while fasting insulin and type 2 diabetes showed a suggestive association that should be further investigated.

Factors Related to Development of Pancreatic Adenocarcinoma in Patients With Chronic Pancreatitis on Long-term Follow-up: A Database Study

BACKGROUND

Chronic pancreatitis (CP) is a risk factor for pancreatic adenocarcinoma (PA). However, little is known about factors related to development of PA in CP.

OBJECTIVE

To evaluate factors associated with PA in CP.

METHODS

A national insurance database of 120 million US patients was used. Adults with an International Classification of Diseases, Ninth Revision (ICD-9) code for CP (577.1) from January 1, 2009, to December 31, 20014, were identified. Patients' age, sex, and ICD-9 codes for PA, bile duct obstruction, alcohol use, diabetes mellitus before and after diagnosis of CP, obesity, tobacco use, and type of insurance were obtained. Patients with CP without a unique identification number, missing dates for insurance coverage period, and with duration to end of follow-up or development of PA less than 2 years were excluded. The Cox proportional hazards regression model was used for analysis.

RESULTS

The final analysis had 30,555 patients with CP including 219 patients (0.72%) with PA. The Cox proportional hazards regression model showed that in patients with CP age (hazard ratio [HR] = 1.07; 95% Confidence Interval [CI] = 1.03-1.1), male sex (HR = 2.1; 95% CI = 1.25-3.54), tobacco use (HR = 1.88; 95% CI = 1.1-3.23), and having commercial insurance (HR = 4.26; 95% CI = 1.63-11.11) were associated with a subsequent medical claim for PA. Duration of bile duct obstruction (HR = 0.999; 95% CI = 0.998-0.999) and presence of diabetes mellitus before CP (HR = 0.35; 95% CI = 0.19-0.63) were inversely related to subsequent diagnosis of PA.

CONCLUSION

PA was diagnosed in 0.72% of the patients with CP at least 2 years after the diagnosis of CP. Increasing age, male sex, tobacco use, having commercial insurance, absence of diabetes mellitus before CP, and shorter duration of bile duct obstruction were associated with a diagnosis of PA in patients with CP.

The association between use of statin or aspirin and pancreatic ductal adenocarcinoma: A nested case-control study in a Korean nationwide cohort

Background

Although several studies have suggested that aspirin and statins may help prevent pancreatic ductal adenocarcinoma (PDAC), this concept has been controversial. This study aimed to evaluate the association between use of statin or aspirin and PDAC in a nationwide large cohort.

Methods

In this nested case‐control study, we used data from a 12‐year nationwide longitudinal cohort in Korea. Cases with PDAC and controls who were matched to cases by age, sex, income, and index year at a 1:5 ratio were established. We used multivariate logistic regression analyses to identify the independent risk factors of PDAC.

Results

We identified a total of 827 patients with PDAC between 2007 and 2013, and included 4135 matched controls. Diabetes mellitus, chronic and acute pancreatitis, pancreatic cystic lesions, and cholelithiasis were independent risk factors for PDAC. Statin use (odds ratio [OR], 0.92; 95% confidence interval [CI] 0.76‐1.11; P = .344; adjusted OR [aOR], 0.70; 95% CI 0.56‐0.87; P = .001) was associated with a reduced risk of PDAC after correction of the confounding factors, but aspirin use (OR, 0.98; 95% CI 0.84‐1.15; P = .838; aOR 0.84; 95% CI 0.70‐1.01, P = .068) was not associated with PDAC. Among the patients with risk factors, both statin use (OR, 0.50; 95% CI 0.38‐0.66; P < .001; aOR, 0.62; 95% CI 0.45‐0.84; P = .002) and aspirin use (OR, 0.48; 95% CI 0.31‐0.67; P < .001; aOR 0.67; 95% CI 0.50‐0.89, P = .006) were associated with a reduced risk of PDAC.

Conclusion

This study suggests that statin use was associated with a reduced risk of PDAC incidence but aspirin use was not. Both statin use and aspirin use were associated a reduced risk of PDAC incidence for patients with risk factors.

L-TRUST: Long-term risk of cancer in patients under statins therapy. A systematic review and meta-analysis

INTRODUCTION

Statins are widely prescribed drugs with established efficacy in primary and secondary prevention of cardiovascular events. Although they are mostly well tolerated, several authors have been emphasizing that the statins' safety profile is not totally clarified especially when considering risk of cancer in patients with long-term exposure to statins. This meta-analysis was aimed at evaluating the risk of cancer in patients with prolonged exposure to statins.

METHODS

Medline, Cochrane library, and clinicaltrials.gov were searched in order to identify studies with a minimum average follow-up of 10 years of exposure to statins and a cancer-related outcome reported. Relative risk (RR) of the primary outcomes and the combined effect was presented using a random-effects model. In the selected randomized control trials (RCT), statin exposure was compared with placebo, and in the selected observational studies, it was compared with no exposure to statins.

RESULTS

We retrieved 1627 studies, of which 15 full-papers were included for final review, five RCT, two cohort studies (CSs), and eight case-control studies (CCs), representing a total of 358 544 patients. Five RCT, two cohort studies (CSs), and eight case-control studies (CCs). No significant differences were found regarding risk of cancer occurrence (RR = 1.08, 0.96-1.21) or cancer mortality (RR = 0.91, 0.80-1.04) due to long-term statin exposure. Regarding all-cause mortality, a protective effect was found (RR = 0.93, 0.90-0.97).

CONCLUSIONS

According to available and published evidence, statins are not associated with an increased risk of cancer after prolonged exposure. These findings strengthen the role of statins in the primary and secondary prevention of cardiovascular events.

Obesity-Induced Adipose Tissue Inflammation as a Strong Promotional Factor for Pancreatic Ductal Adenocarcinoma

Pancreatic ductal adenocarcinoma (PDAC) is expected to soon become the second leading cause of cancer related deaths in the United States. This may be due to the rising obesity prevalence, which is a recognized risk factor for PDAC. There is great interest in deciphering the underlying driving mechanisms of the obesity–PDAC link. Visceral adiposity has a strong correlation to certain metabolic diseases and gastrointestinal cancers, including PDAC. In fact, our own data strongly suggest that visceral adipose tissue inflammation is a strong promoter for PDAC growth and progression in a genetically engineered mouse model of PDAC and diet-induced obesity. In this review, we will discuss the relationship between obesity-associated adipose tissue inflammation and PDAC development, with a focus on the key molecular and cellular components in the dysfunctional visceral adipose tissue, which provides a tumor permissive environment.

Lipophilic statins inhibit YAP nuclear localization, co-activator activity and colony formation in pancreatic cancer cells and prevent the initial stages of pancreatic ductal adenocarcinoma in KrasG12D mice

We examined the impact of statins on Yes-associated Protein (YAP) localization, phosphorylation and transcriptional activity in human and mouse pancreatic ductal adenocarcinoma (PDAC) cells. Exposure of sparse cultures of PANC-1 and MiaPaCa-2 cells to cerivastatin or simvastatin induced a striking re-localization of YAP from the nucleus to the cytoplasm and inhibited the expression of the YAP/TEAD-regulated genes Connective Tissue Growth Factor (CTGF) and Cysteine-rich angiogenic inducer 61 (CYR61). Statins also prevented YAP nuclear import and expression of CTGF and CYR61 stimulated by the mitogenic combination of insulin and neurotensin in dense culture of these PDAC cells. Cerivastatin, simvastatin, atorvastatin and fluvastatin also inhibited colony formation by PANC-1 and MiaPaCa-2 cells in a dose-dependent manner. In contrast, the hydrophilic statin pravastatin did not exert any inhibitory effect even at a high concentration (10 μM). Mechanistically, cerivastatin did not alter the phosphorylation of YAP at Ser¹²⁷ in either PANC-1 or MiaPaCa-2 cells incubated without or with neurotensin and insulin but blunted the assembly of actin stress fiber in these cells. We extended these findings with human PDAC cells using primary KC and KPC cells, (expressing KrasG12D or both KrasG12D and mutant p53, respectively) isolated from KC or KPC mice. Using cultures of these murine cells, we show that lipophilic statins induced striking YAP translocation from the nucleus to the cytoplasm, inhibited the expression of Ctgf, Cyr61 and Birc5 and profoundly inhibited colony formation of these cells. Administration of simvastatin to KC mice subjected to diet-induced obesity prevented early pancreatic acini depletion and PanIN formation. Collectively, our results show that lipophilic statins restrain YAP activity and proliferation in pancreatic cancer cell models in vitro and attenuates early lesions leading to PDAC in vivo.

Central role of Yes-associated protein and WW-domain-containing transcriptional co-activator with PDZ-binding motif in pancreatic cancer development

Pancreatic ductal adenocarcinoma (PDAC) remains a deadly disease with no efficacious treatment options. PDAC incidence is projected to increase, which may be caused at least partially by the obesity epidemic. Significantly enhanced efforts to prevent or intercept this cancer are clearly warranted. Oncogenic KRAS mutations are recognized initiating events in PDAC development, however, they are not entirely sufficient for the development of fully invasive PDAC. Additional genetic alterations and/or environmental, nutritional, and metabolic signals, as present in obesity, type-2 diabetes mellitus, and inflammation, are required for full PDAC formation. We hypothesize that oncogenic KRAS increases the intensity and duration of the growth-promoting signaling network. Recent exciting studies from different laboratories indicate that the activity of the transcriptional co-activators Yes-associated protein (YAP) and WW-domain-containing transcriptional co-activator with PDZ-binding motif (TAZ) play a critical role in the promotion and maintenance of PDAC operating as key downstream target of KRAS signaling. While initially thought to be primarily an effector of the tumor-suppressive Hippo pathway, more recent studies revealed that YAP/TAZ subcellular localization and co-transcriptional activity is regulated by multiple upstream signals. Overall, YAP has emerged as a central node of transcriptional convergence in growth-promoting signaling in PDAC cells. Indeed, YAP expression is an independent unfavorable prognostic marker for overall survival of PDAC. In what follows, we will review studies implicating YAP/TAZ in pancreatic cancer development and consider different approaches to target these transcriptional regulators.

Inverse Association Between Statin Use and Overall Cancer Incidence in Individuals With Hypercholesterolemia, Based on the Korean Health Insurance Service Between 2002 and 2015

The Korean National Health Insurance Service provided the Health Screening Cohort Database. To investigate the cumulative effect of statins on cancer development, we defined statin users as those who used statins during 2002 to 2003 at baseline. Statin users were divided into high and low users. Statin nonusers were defined as individuals who had never used statins during the entire period of 2002 to 2015, despite having hypercholesterolemia. In total, 17 737 statin users and 13 412 statin nonusers were included in the final analyses. The median follow-up duration was 12.6 years. Compared with nonusers, the hazard ratios (95% confidential intervals) for any cancer incidence of low users and high users were 1.047 (0.941-1.164) and 0.663 (0.589-0.747) in men and 1.057 (0.938-1.190) and 0.592 (0.517-0.678) in women, respectively, after fully adjusting for possible confounding factors. An inverse association between statin use and any cancer incidence in individuals with hypercholesterolemia was observed.

Statin Use and Risk of Pancreatic Cancer: An Updated Meta-analysis of 26 Studies

OBJECTIVE

The aim of this study was to explore the relationship between statin use and the risk of pancreatic cancer.

METHODS

Electronic databases were searched to identify relevant studies published until January 2018. The pooled relative risks (RRs) and 95% confidence intervals (CIs) were calculated with random-effects model. Subgroup analyses and sensitivity analysis were also conducted. Cochran Q test and I(2) statistic were used to evaluate the heterogeneity.

RESULTS

Twenty-six studies were included that contained more than 3 million participants and 170,000 pancreatic cancer patients. The overall result demonstrated a significant decrease in pancreatic cancer risk with statin use (RR, 0.84; 95% CI, 0.73-0.97; P = 0.000; I(2) = 84.4%). In subgroup analyses, nonsignificant association was detected between long-term statin use and the risk of pancreatic cancer (RR, 0.98; 95% CI, 0.86-1.11; P = 0.718; I(2) = 0.0%). Meanwhile, there was nonsignificant association between the use of lipophilic statins and the risk of pancreatic cancer (RR, 0.98; 95% CI, 0.84-1.15; P = 0.853; I(2) = 27.2%). No publication bias was found in this meta-analysis.

CONCLUSIONS

The overall result of this meta-analysis supports the hypothesis that statins have a protective effect on pancreatic cancer. Furthermore, high-quality randomized clinical trials and cohort studies are needed to confirm these findings.

Total Serum Cholesterol and Pancreatic Cancer: A Nested Case-Control Study

BACKGROUND

Pancreatic cancer is the third leading cause of cancer-related death in the United States. Total serum cholesterol (TSC) may predict cancer risk, although its role independent of statins remains elusive. We examined the association between TSC and pancreatic cancer risk independent of statins.

METHODS

A nested case-control analysis was conducted among statin-naïve patients within The Health Improvement Network (THIN), a United Kingdom-based general practice database. Cases were >40 years old and diagnosed with pancreatic cancer after at least 6 months of follow-up. Controls were selected by incidence density sampling and matched by age, sex, practice site, and follow-up. Primary exposure was TSC (mmol/L) prior to index date. Conditional logistic regression estimated ORs for pancreatic cancer risk associated with TSC. Sensitivity analyses were conducted among nondiabetics.

RESULTS

Among 1,241 cases and 3,307 matched controls, an average 8% reduction was observed in pancreatic cancer risk per mmol/L increase in TSC [OR 0.92, 95% confidence interval (CI): 0.85-1.00; nondiabetics: OR 0.91, 95% CI: 0.83-0.99]. When TSC was measured at 12-month intervals prior to diagnosis, the OR between TSC and pancreatic cancer was 0.88 at 0 to 12 months (95% CI: 0.77-1.00; nondiabetics: OR 0.81, 95% CI: 0.68-0.96). No significant association was seen at subsequent discrete intervals before index date.

CONCLUSIONS

TSC is a significant predictor of short-term risk for pancreatic cancer. This risk increase associated with lower TSC was independent of statins.

IMPACT

TSC could serve as a biomarker for risk stratification, screening, and early diagnosis of pancreatic cancer in future clinical prediction models.

Statin use is associated to a reduced risk of pancreatic cancer: A meta-analysis

BACKGROUND

Previous studies investigating the association between statin use and pancreatic cancer (PDAC) risk for a possible chemopreventive effect gathered heterogeneous results.

AIMS

To conduct a systematic review and meta-analysis to clarify this association.

METHODS

Comprehensive literature search of articles published up to February 2018, including case-control (CC),cohort studies (C), randomized controlled trials (RCTs) assessing association between statin use and PDAC risk. Studies had to report odds ratio (OR)/relative risk (RR), estimates with 95% confidence interval (CI), or provide data for their calculation. Pooled ORs with 95%CIs were calculated using random effects model, publication bias through Begg and Mazumdar test and heterogeneity by I² value.

RESULTS

27 studies(13 CC, 9C, 5 RCTs) for a total population of 11,975 PDAC/3,433,175 controls contributed to the analysis. The overall pooled result demonstrated a reduced PDAC risk among statin users (OR 0.70; 95% CI 0.60-0.82; p < 0.0001), compared to non-users. Sensitivity analyses suggested the risk reduction to be more important in CC studies, studies conducted in Asia and Europe, in males and atorvastatin users. No publication bias found.

CONCLUSIONS

The present meta-analysis suggests that statin use is associated with an overall PDAC risk reduction of 30%. Further studies are needed to clarify the association.

Statin therapy and association with ovarian cancer risk in the New England Case Control (NEC) study

Statins are widely used to lower blood cholesterol and reduce risk for cardiovascular diseases, but attention has recently focused on a role in cancer prevention or therapy. Here we present data from a large case-control study addressing whether statin use can lower the risk for epithelial ovarian cancer (EOC). Between 1992 and 2008, data including medications used for at least 6 months were collected from 2,040 cases with EOC and 2,100 frequency-matched controls without the disease who participated in the New England Case Control study. We used unconditional logistic regression controlling for matching factors and potential confounders to examine the association between statin use and the risk for EOC. Overall, women who used statins had 32% lower risk of ovarian cancer compared to non-users (Odds ratio (OR) 0.68, 95% Confidence Interval (CI): 0.54-0.85), adjusting for the matching factors and other covariates. The reduced risk was most apparent in women taking a lipophilic statin who began use after age 49, and who had used them 2-4.9 years. Statin use was associated with lower risks for both serous and non-serous histologic subtypes with the strongest effect seen for mucinous and mixed epithelial subtypes. The association became apparent about a decade after the introduction of statins and did not appear to be confounded by indications for use of statins or medications used concomitantly. In this case-control study, statins were found to lower the risk for both serous and non-serous EOC and especially mucinous EOC.

Yes-associated protein (YAP) in pancreatic cancer: at the epicenter of a targetable signaling network associated with patient survival

Pancreatic ductal adenocarcinoma (PDAC) is generally a fatal disease with no efficacious treatment modalities. Elucidation of signaling mechanisms that will lead to the identification of novel targets for therapy and chemoprevention is urgently needed. Here, we review the role of Yes-associated protein (YAP) and WW-domain-containing Transcriptional co-Activator with a PDZ-binding motif (TAZ) in the development of PDAC. These oncogenic proteins are at the center of a signaling network that involves multiple upstream signals and downstream YAP-regulated genes. We also discuss the clinical significance of the YAP signaling network in PDAC using a recently published interactive open-access database (www.proteinatlas.org/pathology) that allows genome-wide exploration of the impact of individual proteins on survival outcomes. Multiple YAP/TEAD-regulated genes, including AJUBA, ANLN, AREG, ARHGAP29, AURKA, BUB1, CCND1, CDK6, CXCL5, EDN2, DKK1, FOSL1,FOXM1, HBEGF, IGFBP2, JAG1, NOTCH2, RHAMM, RRM2, SERP1, and ZWILCH, are associated with unfavorable survival of PDAC patients. Similarly, components of AP-1 that synergize with YAP (FOSL1), growth factors (TGFα, EPEG, and HBEGF), a specific integrin (ITGA2), heptahelical receptors (P2Y₂R, GPR87) and an inhibitor of the Hippo pathway (MUC1), all of which stimulate YAP activity, are associated with unfavorable survival of PDAC patients. By contrast, YAP inhibitory pathways (STRAD/LKB-1/AMPK, PKA/LATS, and TSC/mTORC1) indicate a favorable prognosis. These associations emphasize that the YAP signaling network correlates with poor survival of pancreatic cancer patients. We conclude that the YAP pathway is a major determinant of clinical aggressiveness in PDAC patients and a target for therapeutic and preventive strategies in this disease.

Yes-associated protein (YAP) signaling contributes to pancreatic cancer progression and is associated with poor patient survival. Previous studies have shown that YAP activates genes involved in cell proliferation to incite tumor growth and metastasis. Enrique Rozengurt and colleagues at University of California Los Angeles review the latest knowledge on YAP signaling and used the open access database The Human Protein Atlas to analyze the gene expression profile and prognosis of 176 patients with pancreatic ductal adenocarcinoma. Activation of upstream or downstream elements of the YAP signaling pathway correlated with shorter survival in patients. Conversely, the activation of signaling pathways that oppose YAP signaling were associated with a more favorable prognosis. These findings highlight YAP signaling pathway components as both prognostic markers and potential targets for developing much needed therapeutic and preventative strategies.

Simvastatin inhibits sonic hedgehog signaling and stemness features of pancreatic cancer

Pancreatic ductal adenocarcinoma (PDA) has poor therapeutic options. Recent patient studies indicate that cholesterol-lowering statins have anti-tumor capacities. We examined several established and primary PDA and normal cell lines as well as PDA patient tissues (n = 68). We found that simvastatin inhibited viability, stemness, tumor growth and metastasis and that it enhanced the efficacy of gemcitabine. These changes were associated with modulation of Shh-related gene expression. Overexpression of Shh prevented the anti-cancer effect of simvastatin, and inhibition of Shh mimicked the simvastatin effect. In PDA tissues, expression levels of Shh, downstream mediators of Shh and progression markers, namely, cMet, CxCR4 and Vimentin, were lower when patients were prescribed statin medication prior to surgery. These results suggested that statins are cost effective and well-tolerated drugs for prevention and co-treatment of PDA.

Pancreatic Adenocarcinoma Therapeutic Targets Revealed by Tumor-Stroma Cross-Talk Analyses in Patient-Derived Xenografts

Preclinical models based on patient-derived xenografts have remarkable specificity in distinguishing transformed human tumor cells from non-transformed murine stromal cells computationally. We obtained 29 pancreatic ductal adenocarcinoma (PDAC) xenografts from either resectable or non-resectable patients (surgery and endoscopic ultrasound-guided fine-needle aspirate, respectively). Extensive multiomic profiling revealed two subtypes with distinct clinical outcomes. These subtypes uncovered specific alterations in DNA methylation and transcription as well as in signaling pathways involved in tumor-stromal cross-talk. The analysis of these pathways indicates therapeutic opportunities for targeting both compartments and their interactions. In particular, we show that inhibiting NPC1L1 with Ezetimibe, a clinically available drug, might be an efficient approach for treating pancreatic cancers. These findings uncover the complex and diverse interplay between PDAC tumors and the stroma and demonstrate the pivotal role of xenografts for drug discovery and relevance to PDAC.

KRAS, YAP, and obesity in pancreatic cancer: A signaling network with multiple loops

Pancreatic ductal adenocarcinoma (PDAC) continues to be a lethal disease with no efficacious treatment modalities. The incidence of PDAC is expected to increase, at least partially because of the obesity epidemic. Increased efforts to prevent or intercept this disease are clearly needed. Mutations in KRAS are initiating events in pancreatic carcinogenesis supported by genetically engineered mouse models of the disease. However, oncogenic KRAS is not entirely sufficient for the development of fully invasive PDAC. Additional genetic mutations and/or environmental, nutritional, and metabolic stressors, e.g. inflammation and obesity, are required for efficient PDAC formation with activation of KRAS downstream effectors. Multiple factors "upstream" of KRAS associated with obesity, including insulin resistance, inflammation, changes in gut microbiota and GI peptides, can enhance/modulate downstream signals. Multiple signaling networks and feedback loops "downstream" of KRAS have been described that respond to obesogenic diets. We propose that KRAS mutations potentiate a signaling network that is promoted by environmental factors. Specifically, we envisage that KRAS mutations increase the intensity and duration of the growth-promoting signaling network. As the transcriptional activator YAP plays a critical role in the network, we conclude that the rationale for targeting the network (at different points), e.g. with FDA approved drugs such as statins and metformin, is therefore compelling.

Exclusive and Combined Use of Statins and Aspirin and the Risk of Pancreatic Cancer: a Case-Control Study

Data on the association between aspirin and statin use and Pancreatic Ductal AdenoCarcinoma (PDAC) risk are conflicting. These drugs are often co-prescribed, but no studies evaluated the potential combined or confounding effect of the two at the same time. We aimed to investigate the association between aspirin and statin exclusive and combined use and PDAC occurrence. Data on environmental factors, family and medical history were screened in a case-control study. PDAC cases were matched to controls for age and gender. Power calculation performed ahead. Odds ratios (OR) and 95% confidence intervals(CI) were obtained from multivariable logistic regression analysis. In 408 PDAC patients and 816 matched controls, overall statin (OR 0.61; 95%CI,0.43-0.88), but not aspirin use was associated to reduced PDAC risk. Compared to non-users, exclusive statin (OR 0.51; 95%CI,0.32-0.80) and exclusive aspirin users (OR 0.64; 95%CI,0.40-1.01) had reduced PDAC risk. Concomitant statin and aspirin use did not further reduce the risk compared with statin use alone and no interaction was evident. Statin protective association was dose-dependent, and consistent in most subgroups, being stronger in smokers, elderly, obese and non-diabetic patients. The present study suggests that statin use is associated to reduced PDAC risk, supporting a chemopreventive action of statins on PDAC.

A screen for inducers of bHLH activity identifies pitavastatin as a regulator of p21, Rb phosphorylation and E2F target gene expression in pancreatic cancer

The average survival for patients with Pancreatic Ductal Adenocarcinoma (PDA) is merely 6 months, underscoring the need for new therapeutic approaches. During PDA progression, pancreatic acinar cells lose activity of the ClassI/II bHLH factors that regulate quiescence. We previously found that promoting transcriptional activity of the Class I bHLH factor E47 in highly aggressive PDA cells induced stable growth arrest in vitro and in vivo. To translate these findings for clinical utility, we developed a high throughput screening platform to identify small molecule inducers of Class I/II bHLH activity. A screen of 4,375 known drugs identified 70 bHLH activators. Prominent among the hits were members of the statin class of HMG-CoA reductase inhibitors, cholesterol lowering drugs that are also being evaluated in cancer. Studies with pitavastatin in primary patient derived tumor cells and established PDA lines, revealed dose dependent growth inhibition. At the molecular level, pitavastatin induced expression of the cyclin dependent kinase (CDK) inhibitor p21 in a cholesterol independent manner, blocked repressive phosphorylation of the Retinoblastoma tumor suppressor protein at CDK targeted sites, and reduced expression of E2F target genes required for progression through the G1/S boundary. Together, the data provide new insight into mechanisms by which statins constrain proliferation in cancer and establish the effectiveness of a novel screening platform to identify small molecules of clinical relevance in pancreatic cancer.

Variability in statin-induced changes in gene expression profiles of pancreatic cancer

Statins, besides being powerful cholesterol-lowering drugs, also exert potent anti-proliferative activities. However, their anti-cancer efficacy differs among the individual statins. Thus, the aim of this study was to identify the biological pathways affected by individual statins in an in vitro model of human pancreatic cancer. The study was performed on a human pancreatic cancer cell line MiaPaCa-2, exposed to all commercially available statins (12 μM, 24 h exposure). DNA microarray analysis was used to determine changes in the gene expression of treated cells. Intracellular concentrations of individual statins were measured by UPLC (ultra performance liquid chromatography)-HRMS (high resolution mass spectrometer). Large differences in the gene transcription profiles of pancreatic cancer cells exposed to various statins were observed; cerivastatin, pitavastatin, and simvastatin being the most efficient modulators of expression of genes involved namely in the mevalonate pathway, cell cycle regulation, DNA replication, apoptosis and cytoskeleton signaling. Marked differences in the intracellular concentrations of individual statins in pancreatic cancer cells were found (>11 times lower concentration of rosuvastatin compared to lovastatin), which may contribute to inter-individual variability in their anti-cancer effects. In conclusion, individual statins exert different gene expression modulating effects in treated pancreatic cancer cells. These effects may be partially caused by large differences in their bioavailability. We report large differences in gene transcription profiles of pancreatic cancer cells exposed to various statins. These data correlate to some extent with the intracellular concentrations of statins, and may explain the inter-individual variability in the anti-cancer effects of statins.

A Clinical Prediction Model to Assess Risk for Pancreatic Cancer Among Patients With New-Onset Diabetes

BACKGROUND & AIMS

Approximately 50% of all patients with pancreatic ductal adenocarcinoma (PDA) develop diabetes mellitus before their cancer diagnosis. Screening individuals with new-onset diabetes might allow earlier diagnosis of PDA. We sought to develop and validate a PDA risk prediction model to identify high-risk individuals among those with new-onset diabetes.

METHODS

We conducted a retrospective cohort study in a population representative database from the United Kingdom. Individuals with incident diabetes after the age of 35 years and 3 or more years of follow-up after diagnosis of diabetes were eligible for inclusion. Candidate predictors consisted of epidemiologic and clinical characteristics available at the time of diabetes diagnosis. Variables with P values <.25 in the univariable analyses were evaluated using backward stepwise approach. Model discrimination was assessed using receiver operating characteristic curve analysis. Calibration was evaluated using the Hosmer-Lemeshow test. Results were internally validated using a bootstrapping procedure.

RESULTS

We analyzed data from 109,385 patients with new-onset diabetes. Among them, 390 (0.4%) were diagnosed with PDA within 3 years. The final model (area under the curve, 0.82; 95% confidence interval, 0.75-0.89) included age, body mass index, change in body mass index, smoking, use of proton pump inhibitors, and anti-diabetic medications, as well as levels of hemoglobin A1C, cholesterol, hemoglobin, creatinine, and alkaline phosphatase. Bootstrapping validation showed negligible optimism. If the predicted risk threshold for definitive PDA screening was set at 1% over 3 years, only 6.19% of the new-onset diabetes population would undergo definitive screening, which would identify patients with PDA with 44.7% sensitivity, 94.0% specificity, and a positive predictive value of 2.6%.

CONCLUSIONS

We developed a risk model based on widely available clinical parameters to help identify patients with new-onset diabetes who might benefit from PDA screening.

Statins and pancreatic cancer

Pancreatic cancer remains among the most lethal cancers, despite ongoing advances in treatment for all stages of the disease. Disease prevention represents another opportunity to improve patient outcome, with metabolic syndrome and its components, such as diabetes, obesity and dyslipidemia, having been recognized as modifiable risk factors for pancreatic cancer. In addition, statins have been shown to potentially reduce pancreatic cancer risk and to improve survival in patients with a combination of metabolic syndrome and pancreatic cancer. Furthermore, preclinical studies have demonstrated that statins exhibit antitumor effects in pancreatic cancer cell lines in vitro and animal models in vivo, in addition to delaying the progression of pancreatic intraepithelial neoplasia to pancreatic ductal adenocarcinoma (PDAC) and inhibiting PDAC formation in conditional K-Ras mutant mice. The mechanisms by which statins produce anticancer effects remain poorly understood, although appear to involve inhibition of the mevalonate/cholesterol synthesis pathway, thus blocking the synthesis of intermediates important for prenylation and activation of the Ras/mitogen-activated protein kinase 1 signaling pathway. Furthermore, statins have been identified to modulate the phosphoinositide 3-kinase/Akt serine/threonine kinase 1 and inflammation signaling pathways, and to alter the expression of genes involved in lipid metabolism, which are important for PDAC growth and proliferation. In addition, statins have been demonstrated to exhibit further antitumor mechanisms in a number of other cancer types, which are beyond the scope of the present review. In the present review, current evidence highlighting the potential of statins as chemopreventive agents in pancreatic cancer is presented, and the antitumor mechanisms of statins elucidated thus far in this disease are discussed.

Simvastatin attenuates macrophage-mediated gemcitabine resistance of pancreatic ductal adenocarcinoma by regulating the TGF-β1/Gfi-1 axis

Pancreatic ductal adenocarcinoma (PDAC) is a highly lethal malignancy with an intrinsic resistance to almost all chemotherapeutic drugs, including gemcitabine. An abundance of tumor-associated macrophages (TAMs), which can promote the resistance of PDAC to gemcitabine, has been observed in the microenvironments of several tumors. In this study, we confirmed that incubation in TAM-conditioned medium (TAM-CM) reduces the gemcitabine-induced apoptosis of PDAC cells. Simvastatin attenuated the TAM-mediated resistance of PDAC cells to gemcitabine. Further investigation found that simvastatin reversed the TAM-mediated down-regulation of Gfi-1 and up-regulation of CTGF and HMGB1. Simvastatin induced Gfi-1 expression, which increased the sensitivity of PDAC cells to gemcitabine by decreasing TGF-β1 secretion by TAMs. A luciferase reporter assay and ChIP assay revealed that Gfi-1 directly repressed the transcription of CTGF and HMGB1. Simvastatin also reversed the effects of gemcitabine on the expression of TGF-β1 and Gfi-1 and reduced the resistance of PDAC to gemcitabine in vivo. These results provide the first evidence that simvastatin attenuates the TAM-mediated gemcitabine resistance of PDAC by blocking the TGF-β1/Gfi-1 axis. These findings suggest the TGF-β1/Gfi-1 axis as a novel therapeutic target for treating PDAC.

Nonsteroidal anti-inflammatory drugs, statins, and pancreatic cancer risk: a population-based case-control study

PURPOSE

Studies suggest that aspirin, other nonsteroidal anti-inflammatory drugs (NSAIDs), and statins may reduce risk of some cancers. However, findings have been conflicting as to whether these agents reduce the risk of pancreatic cancer.

METHODS

We used data from the Queensland Pancreatic Cancer Study, a population-based case-control study. In total, 704 cases and 711 age- and sex-matched controls were recruited. Participants completed an interview in which they were asked about history of NSAID and statin use. We included 522 cases and 653 controls who had completed the medication section of the interview in this analysis. Unconditional multivariable logistic regression was used to estimate associations between medication use and pancreatic cancer.

RESULTS

We found no consistent evidence of an association between use of NSAIDs or statins and risk of pancreatic cancer. There was some suggestion of a protective effect in infrequent users of selective COX-2 inhibitors, but no association in more frequent users. We did not find evidence of protective effects in analyses stratified by sex, smoking status, time between diagnosis and interview, or presence/absence of metastases.

CONCLUSIONS

Overall, our results do support the hypothesis that use of NSAIDs or statins may reduce the odds of developing pancreatic cancer.

Regulatory properties of statins and rho gtpases prenylation inhibitiors to stimulate melanoma immunogenicity and promote anti-melanoma immune response

Melanoma is a highly lethal cutaneous tumor, killing affected patients through development of multiple poorly immunogenic metastases. Suboptimal activation of immune system by melanoma cells is often due to molecular modifications occurring during tumor progression that prevent efficient recognition of melanoma cells by immune effectors. Statins are HMG-CoA reductase inhibitors, which block the mevalonate synthesis pathway, used by millions of people as hypocholesterolemic agents in cardiovascular and cerebrovascular diseases. They are also known to inhibit Rho GTPase activation and Rho dependent signaling pathways. Rho GTPases are regarded as molecular switches that regulate a wide spectrum of cellular functions and their dysfunction has been characterized in various oncogenic process notably in melanoma progression. Moreover, these molecules can modulate the immune response. Since 10 years we have demonstrated that Statins and other Rho GTPases inhibitors are critical regulators of molecules involved in adaptive and innate anti-melanoma immune response. In this review we summarize our major observations demonstrating that these pharmacological agents stimulate melanoma immunogenicity and suggest a potential use of these molecules to promote anti-melanoma immune response.

The Role of Common Pharmaceutical Agents on the Prevention and Treatment of Pancreatic Cancer

Survival from pancreatic cancer remains poor. Conventional treatment has resulted in only marginal improvements in survival compared with survival in the previous several decades. Thus, considerable interest has emerged regarding the potential use of common pharmaceutical agents as chemopreventative and chemotherapeutic options. Aspirin, metformin, statins, β-blockers, and bisphosphonates have biologically plausible mechanisms to inhibit pancreatic neoplasia, whereas dipeptidyl-peptidase 4 inhibitors may promote it. Regardless, real-world epidemiological data remain inconclusive. This review examines the hypotheses, evidence, and current state of the literature for each of these medications and their potential roles in the prevention and treatment of pancreatic cancer.

Pancreatic Cancer Chemoprevention Translational Workshop: Meeting Report

Pancreatic cancer is the fourth leading cause of cancer related deaths in the United States with a 5-year survival rate of less than 10%. The Division of Cancer Prevention of the National Cancer Institute sponsored the Pancreatic Cancer Chemoprevention Translational Workshop on September 10 to 11, 2015. The goal of the workshop was to obtain information regarding the current state of the science and future scientific areas that should be prioritized for pancreatic cancer prevention research, including early detection and intervention for high-risk precancerous lesions. The workshop addressed the molecular/genetic landscape of pancreatic cancer and precursor lesions, high-risk populations and criteria to identify a high-risk population for potential chemoprevention trials, identification of chemopreventative/immunopreventative agents, and use of potential biomarkers and imaging for assessing short-term efficacy of a preventative agent. The field of chemoprevention for pancreatic cancer is emerging, and this workshop was organized to begin to address these important issues and promote multi-institutional efforts in this area. The meeting participants recommended the development of an National Cancer Institute working group to coordinate efforts, provide a framework, and identify opportunities for chemoprevention of pancreatic cancer.

Modifiable and non-modifiable risk factors for pancreatic cancer: A review

Pancreatic ductal adenocarcinoma is associated with a poor prognosis and a high case-fatality rate. The reasons for poor prognosis are low rates of curative resection due to local infiltration and distant metastasis. To increase survival rates of patients with pancreatic cancer, early detection through surveillance and screening is important. However, screening could only be cost-effective in high-risk populations. Identification of significant risk factors therefore assumes significance. Risk factors could be non-modifiable or modifiable. Non-modifiable risk factors include increasing age, familial cancer syndromes, Afro-American race, hereditary and other forms of chronic pancreatitis, diabetes, and non-O blood group. Important modifiable risk factors include smoking, obesity, dietary factors such as non-vegetarian diet, and toxins. Preventive strategies at the population level and an effective screening program targeted at high-risk people may help in prevention and early detection of pancreatic ductal adenocarcinoma.

Heme oxygenase is not involved in the anti-proliferative effects of statins on pancreatic cancer cells

Background

Pancreatic cancer is recognized as one of the most fatal tumors due to its aggressiveness and resistance to therapy. Statins were previously shown to inhibit the proliferation of cancer cells via various signaling pathways. In healthy tissues, statins activate the heme oxygenase pathway, nevertheless the role of heme oxygenase in pancreatic cancer is still controversial. The aim of this study was to evaluate, whether anti-proliferative effects of statins in pancreatic cancer cells are mediated via the heme oxygenase pathway.

Methods

In vitro effects of various statins and hemin, a heme oxygenase inducer, on cell proliferation were evaluated in PA-TU-8902, MiaPaCa-2 and BxPC-3 human pancreatic cancer cell lines. The effect of statins on heme oxygenase activity was assessed and heme oxygenase-silenced cells were used for pancreatic cancer cell proliferation studies. Cell death rate and reactive oxygen species production were measured in PA-TU-8902 cells, followed by evaluation of the effect of cerivastatin on GFP-K-Ras trafficking and expression of markers of invasiveness, osteopontin (SPP1) and SOX2.

Results

While simvastatin and cerivastatin displayed major anti-proliferative properties in all cell lines tested, pravastatin did not affect the cell growth at all. Strong anti-proliferative effect was observed also for hemin. Co-treatment of cerivastatin and hemin increased anti-proliferative potential of these agents, via increased production of reactive oxygen species and cell death compared to individual treatment. Heme oxygenase silencing did not prevent pancreatic cancer cells from the tumor-suppressive effect of cerivastatin or hemin. Cerivastatin, but not pravastatin, protected Ras protein from trafficking to the cell membrane and significantly reduced expressions of SPP1 (p < 0.05) and SOX2 (p < 0.01).

Conclusions

Anti-proliferative effects of statins and hemin on human pancreatic cancer cell lines do not seem to be related to the heme oxygenase pathway. While hemin triggers reactive oxygen species-induced cell death, cerivastatin targets Ras protein trafficking and affects markers of invasiveness.