Allergies and the risk of pancreatic cancer: a meta-analysis with review of epidemiology and biological mechanisms

Pancreatic Cancer: A Review of Risk Factors

Pancreatic adenocarcinoma is one of the most lethal types of gastrointestinal cancer despite the latest medical advances. Its incidence has continuously increased in recent years in developed countries. The location of the pancreas can result in the initial symptoms of neoplasia being overlooked, which can lead to a delayed diagnosis and a subsequent reduction in the spectrum of available therapeutic options. The role of modifiable risk factors in pancreatic cancer has been extensively studied in recent years, with smoking and alcohol consumption identified as key contributors. However, the few screening programs that have been developed focus exclusively on genetic factors, without considering the potential impact of modifiable factors on disease occurrence. Thus, fully understanding and detecting the risk factors for pancreatic cancer represents an important step in the prevention and early diagnosis of this type of neoplasia. This review reports the available evidence on different risk factors and identifies the areas that could benefit the most from additional studies.

Allergies and risk of head and neck cancer: a case-control study

Although the relationship between allergies and cancer has been investigated extensively, the role of allergies in head and neck cancer (HNC) appears less consistent. It is unclear whether allergies can independently influence the risk of HNC in the presence of substantial environmental risk factors, including consumption of alcohol, betel quid, and cigarettes. This study aims to find this association. We examined the relationship between allergies and HNC risk in a hospital-based case-control study with 300 cases and 375 matched controls. Logistic regression models were used to estimate odds ratios (OR) and 95% confidence intervals, controlling for age, sex, tobacco smoking and opium usage history, alcohol consumption, and socioeconomic status. Our study showed a significant reduction in the risk of HNC associated with allergy symptoms after adjusting for confounders. The risk of HNC was greatly reduced among those with any type of allergy (OR 0.42, 95% CI 0.28, 0.65). The ORs were considerably reduced by 58-88% for different kinds of allergies. The risk of HNC reduction was higher in allergic women than in allergic men (71% vs. 49%). Allergies play an influential role in the risk of HNC development. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are necessary to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help to devise effective strategies to reduce and treat HNC.

Analysis of exposome and genetic variability suggests stress as a major contributor for development of pancreatic ductal adenocarcinoma

BACKGROUND

The current knowledge on pancreatic ductal adenocarcinoma (PDAC) risk factors is limited and no study has comprehensively tested the exposome in combination with the genetic variability in relation to the disease susceptibility.

AIM

The aim of this study was to analyze the exposome and its interaction with known genetic susceptibility loci, in relation to PDAC risk.

METHODS

A case-control study nested in UK Biobank cohort was conducted on 816 PDAC cases and 302,645 controls. A total of 347 exposure variables, and a polygenic risk score (PRS) were analyzed through logistic regression. Gene-environment interaction analyses were conducted.

RESULTS

A total of 52 associations under the Bonferroni corrected threshold of p < 1.46 × 10-4 were observed. Known risk factors such as smoking, pancreatitis, diabetes, PRS, heavy alcohol drinking and overweight were replicated in this study. As for novel associations, a clear indication for length and intensity of mobile phone use and the stress-related factors and stressful events with increase of PDAC risk was observed. Although the PRS was associated with PDAC risk (P = 2.09 × 10-9), statistically significant gene-exposome interactions were not identified.

CONCLUSION

In conclusion, our results suggest that a stressful lifestyle and sedentary behaviors may play a major role in PDAC susceptibility independently from the genetic background.

Allergy History and Immunotherapy Response in Patients With Recurrent/Metastatic Head and Neck Squamous Cell Carcinoma

OBJECTIVE

This study examines the association between patient-reported allergy history and immune checkpoint inhibition (ICI) response in patients with recurrent or metastatic head and neck squamous cell carcinoma (RMHNSCC).

STUDY DESIGN

Retrospective cohort study.

SETTING

Academic tertiary care hospital.

METHODS

Data were collected from the electronic medical records on baseline age, sex, allergy history, human papillomavirus status, T-stage, N-stage, smoking status, and survival for patients with and without an allergy history. The primary outcome was ICI response defined as complete or partial response by the RECIST criteria. Chi-square and logistic regression analyses were conducted to compare rates and odds of ICI response. Kaplan-Meier analyses were used to compare survival between groups.

RESULTS

Our study included 52 patients with an allergy history and 36 patients without an allergy history. The groups were similar in age, sex, HPV status, smoking status, and T- and N-stage. Patients with an allergy history (17/52, 32.1%) had a greater ICI response rate than patients without allergy history (4/36, 11.1%) (P = .02). After adjusting for HPV, patients with allergies had 3.93 (1.19-13.00) times increased odds of ICI response compared to patients without allergies. The median progression-free survival was 6.0 and 4.2 months for patients with and without an allergy history respectively (log-rank, P = .04). The median overall survival was 25.0 and 11.1 months for patients with and without an allergy history respectively (log-rank, P = .002).

CONCLUSION

Patient-reported allergy history was associated with ICI response in patients with RMHNSCC, underscoring the potential clinical utility of allergy history in estimating ICI response.

Allergic Rhinitis and Cancer Risk: A Two-Sample Mendelian Randomization Study

Background: There is increasing evidence that allergic rhinitis (AR) is associated with cancer. However, these results are inconsistent. Because of common risk factors, there may be reverse causality and confounding factors that affect our understanding of the relationship between AR and cancer. We aimed to explore the role of AR in cancer development using Mendelian randomization (MR) analysis. Materials and Methods: We performed a two-sample MR analysis using summary data from genome-wide association studies (GWAS). Single nucleotide polymorphisms (SNPs) strongly associated with AR (or hay fever) were used as instrumental variables, mainly using the inverse variance weighted analysis method, supplemented by MR Egger, maximum likelihood, weighted media, and penalized weighted media for MR analysis. Sensitivity analyses included heterogeneity and horizontal pleiotropy; and leave-one-out analyses were performed to test the robustness of our results. Results: MR analysis revealed no evidence of a causal relationship between AR and any of the examined cancers (all p > 0.05). The results using five different analytical approaches were similar. Sensitivity analyses showed no evidence of heterogeneity nor horizontal pleiotropy. According to the leave-one-out sensitivity analyses, no individual SNP was significantly influencing the causal effect of AR on cancers. Conclusions: These findings do not provide evidence to support that AR has a large impact on the risk of eight common cancers in the European population. However, we cannot rule out a very minor effect of AR on cancer. Further large-scale studies are necessary to validate our findings.

Allergic Diseases and Risk of Malignancy of Gastrointestinal Cancers

The aim of this study was to investigate the effect of allergic diseases, including allergic rhinitis, asthma, and atopic dermatitis, on the development of gastrointestinal (GI) cancers. We analyzed 9,892,633 Korean adults who underwent a medical check-up in the year 2009, and they were followed up until the year 2017. Allergic diseases and cancers were defined using the International Classification of Disease Codes. A Cox proportional hazards model was adapted to calculate the hazard ratios (HRs) and 95% confidence intervals (CIs). During a 7.3-year follow-up period, 48,045 patients were diagnosed with cancer. For all-combined allergic diseases, significant inverse associations were observed for cancers of the esophagus, stomach, colorectum, and liver (adjusted hazard ratios (aHRs [95% confidence interval, CI] 0.86 [0.82-0.91], 0.93 [0.91-0.94], 0.95 [0.93-0.96], and 0.90 [0.88-0.92], respectively). The sex-stratified analysis showed that the preventive effect of allergic diseases was persistent in gastric, colorectal, and liver cancers regardless of sex, while the inverse associations with esophageal and pancreatic cancers were observed only in men (aHR [95% CI] 0.84 [0.80-0.89] and 0.96 [0.93-0.99]). Allergic diseases, particularly allergic rhinitis, in adults were significantly associated with a decreased risk of most GI cancers, except for gallbladder and biliary tract cancers.

Diagnostic and prognostic role of circRNAs in pancreatic cancer: a meta-analysis

Background

Circular RNAs (circRNAs) are types of endogenous noncoding RNAs produced by selective splicing that are expressed highly specifically in various organisms and tissues and have numerous clinical implications in the regulation of cancer development and progression. Since circRNA is resistant to digestion by ribonucleases and has a long half-life, there is increasing evidence that circRNA can be used as an ideal candidate biomarker for the early diagnosis and prognosis of tumors. In this study, we aimed to reveal the diagnostic and prognostic value of circRNA in human pancreatic cancer (PC).

Methods

A systematic search for publications from inception to 22 July 2022 was conducted on Embase, PubMed, Web of Science (WOS), and the Cochrane Library databases. Available studies that correlated circRNA expression in tissue or serum with the clinicopathological, diagnostic, and prognostic values of PC patients were enrolled. Odds ratios (ORs) and corresponding 95% confidence intervals (CIs) were used to evaluate clinical pathological characteristics. Area under the curve (AUC), sensitivity, and specificity were adopted to assess diagnostic value. Hazard ratios (HRs) were utilized to assess disease-free survival (DFS) and overall survival (OS).

Results

This meta-analysis enrolled 32 eligible studies, including six on diagnosis and 21 on prognosis, which accounted for 2,396 cases from 245 references. For clinical parameters, high expression of carcinogenic circRNA was significantly associated with degree of differentiation (OR = 1.85, 95% CI = 1.47-2.34), TNM stage (OR = 0.46, 95% CI = 0.35-0.62), lymph node metastasis (OR = 0.39, 95% CI = 0.32-0.48), and distant metastasis (OR = 0.26, 95% CI = 0.13-0.51). As for clinical diagnostic utility, circRNA could discriminate patients with pancreatic cancer from controls, with an AUC of 0.86 (95% CI: 0.82-0.88), a relatively high sensitivity of 84%, and a specificity of 80% in tissue. In terms of prognostic significance, carcinogenic circRNA was correlated with poor OS (HR = 2.00, 95% CI: 1.76-2.26) and DFS (HR = 1.96, 95% CI: 1.47-2.62).

Conclusion

In summary, this study demonstrated that circRNA may act as a significant diagnostic and prognostic biomarker for pancreatic cancer.

Mycoviruses in Fungi: Carcinogenesis of Fungal Agents May Not Always Be Mycotoxin Related

Certain viruses have been found to induce diverse biological pathways to carcinogenesis, evidenced by the presence of viral gene products in some tumors. Despite the fact that many fungal agents contain mycoviruses, until recently, their possible direct effects on human health, including carcinogenesis and leukemogenesis, had not been explored. In this regard, most studies of fungal agents have rightly concentrated on their mycotoxin formation and effects. Recently, the direct role of yeasts and fungi in the etiology of cancers, including leukemia, have been investigated. While greater attention has been placed on the carcinogenic effects of Candida, the role of filamentous fungi in carcinogenesis has also been explored. Recent findings from studies using the enzyme-linked immunosorbent assay (ELISA) technique indicate that the plasma of patients with acute lymphoblastic leukemia (ALL) uniformly contains antibodies for a certain mycovirus-containing Aspergillus flavus, while controls are negative. The exposure of mononuclear leukocytes from patients with ALL in full remission, and long-term survivors, to the product of this organism was reported to result in the re-development of typical genetics and cell surface phenotypes characteristic of active ALL. Mycoviruses are known to be able to significantly alter the biological characteristics and functions of their host. The possible carcinogenic and leukemogenic role of mycoviruses, with and without their host, needs to be further investigated.

Eczema as a protective factor for brain cancer: a meta-analysis

BACKGROUND

Brain cancer is one of the most aggressive cancer types owing to poor treatment effects. Epidemiological studies have demonstrated that allergies may increase the disease risk. Therefore, this study evaluated the association between eczema and the risk of various brain cancers.

METHODS

We systematically searched the PubMed and Embase databases from their inception until June 23, 2022. Two reviewers independently reviewed and screened the articles, extracted data, assessed the study quality, and pooled the results. Stata software was used to generate pooled odds ratios and 95% confidence intervals (CIs).

RESULTS

We included 20 studies comprising 5,117,222 patients that investigated the relationship between eczema and brain cancer. Eczema was significantly inversely associated with the risk of brain cancer (odds ratio [OR], 0.82; 95% CI, 0.77-0.87), glioma (OR, 0.53; 95% CI, 0.14-2.02), meningioma (OR, 0.74; 95% CI, 0.66-0.84), and acoustic neuroma (OR, 0.60; 95% CI, 0.41-0.88). Interesting, The strong correlation between eczema and the reduced risk of brain cancer was observed in people over 16 years old (OR, 0.79; 95% CI, 0.71-0.88), but not in those under 16 years old (OR, 0.94; 95% CI, 0.79-1.11). In addition, subgroup analyses found that eczema significantly decreased the glioma risk in Europeans (OR, 0.73; 95% CI, 0.65-0.82) but not Australians (OR, 0.53; 95% CI, 0.14-2.02) or Americans (OR, 1.01; 95% CI, 0.69-1.46).

CONCLUSION

Eczema may be considered as a potential protective factor of brain cancer in population aged over 16 years. However, this relationship requires verification using large-scale clinical data.

Pancreatic Adenocarcinoma: Trends in Epidemiology, Risk Factors, and Outcomes

Pancreatic cancer is one of the most lethal cancers in the world; it is a silent disease in which symptoms do not present until advanced stages, thereby reducing the 5-year survival rate to 10%. The global burden of pancreatic cancer has doubled over the past 25 years despite advancements in medicine. This review aims to discuss the global trends and disparities in pancreatic cancer, as well as the up-to-date literature on the known risk factors. A better understanding of these risk factors will reduce mortality by providing opportunities to screen these patients as well as counseling on lifestyle modifications.

Immunotherapy as a Therapeutic Strategy for Gastrointestinal Cancer-Current Treatment Options and Future Perspectives

Gastrointestinal (GI) cancer constitutes a highly lethal entity among malignancies in the last decades and is still a major challenge for cancer therapeutic options. Despite the current combinational treatment strategies, including chemotherapy, surgery, radiotherapy, and targeted therapies, the survival rates remain notably low for patients with advanced disease. A better knowledge of the molecular mechanisms that influence tumor progression and the development of optimal therapeutic strategies for GI malignancies are urgently needed. Currently, the development and the assessment of the efficacy of immunotherapeutic agents in GI cancer are in the spotlight of several clinical trials. Thus, several new modalities and combinational treatments with other anti-neoplastic agents have been identified and evaluated for their efficiency in cancer management, including immune checkpoint inhibitors, adoptive cell transfer, chimeric antigen receptor (CAR)-T cell therapy, cancer vaccines, and/or combinations thereof. Understanding the interrelation among the tumor microenvironment, cancer progression, and immune resistance is pivotal for the optimal therapeutic management of all gastrointestinal solid tumors. This review will shed light on the recent advances and future directions of immunotherapy for malignant tumors of the GI system.

IgE-Based Therapeutic Combination Enhances Antitumor Response in Preclinical Models of Pancreatic Cancer

Pancreatic ductal adenocarcinoma (PDAC) represents 3% of all cancer cases and 7% of all cancer deaths in the United States. Late diagnosis and inadequate response to standard chemotherapies contribute to an unfavorable prognosis and an overall 5-year survival rate of less than 10% in PDAC. Despite recent advances in tumor immunology, tumor-induced immunosuppression attenuates the immunotherapy response in PDAC. To date, studies have focused on IgG-based therapeutic strategies in PDAC. With the recent interest in IgE-based therapies in multiple solid tumors, we explored the MUC1-targeted IgE potential against pancreatic cancer. Our study demonstrates the notable expression of FceRI (receptor for IgE antibody) in tumors from PDAC patients. Our study showed that administration of MUC1 targeted-IgE (mouse/human chimeric anti-MUC1.IgE) antibody at intermittent levels in combination with checkpoint inhibitor (anti-PD-L1) and TLR3 agonist (PolyICLC) induces a robust antitumor response that is dependent on NK and CD8 T cells in pancreatic tumor-bearing mice. Subsequently, our study showed that the antigen specificity of the IgE antibody plays a vital role in executing the antitumor response as nonspecific IgE, induced by ovalbumin (OVA), failed to restrict tumor growth in pancreatic tumor-bearing mice. Utilizing the OVA-induced allergic asthma-PDAC model, we demonstrate that allergic phenotype induced by OVA cannot restrain pancreatic tumor growth in orthotopic tumor-bearing mice. Together, our data demonstrate the novel tumor protective benefits of tumor antigen-specific IgE-based therapeutics in a preclinical model of pancreatic cancer, which can open new avenues for future clinical interventions.

No association between alcohol consumption and pancreatic cancer even among individuals genetically susceptible to the carcinogenicity of alcohol

Inconsistent results have been reported for the association between alcohol use and pancreatic cancer, particularly at low levels of alcohol consumption. Individuals genetically susceptible to the carcinogenic effect of alcohol might have higher pancreatic cancer risk after drinking alcohol. The current study investigated the association between alcohol use and pancreatic cancer with 419 pancreatic cancer cases and 963 controls recruited by a hospital-based case-control study in Taiwan. Gene-environment interaction between alcohol use and polymorphisms of two ethanol-metabolizing genes, ADH1B and ALDH2, on pancreatic risk was evaluated. Our results showed no significant association between alcohol drinking and an increased pancreatic cancer risk, even at high levels of alcohol consumption. Even among those genetically susceptible to the carcinogenic effect of alcohol (carriers of ADH1B*2/*2(fast activity) combined with ALDH2*1/*2(slow activity) or ALDH2*2/*2(almost non-functional)), no significant association between alcohol use and pancreatic cancer was observed. Overall, our results suggested that alcohol drinking is not a significant contributor to the occurrence of pancreatic cancer in Taiwan.

Pancreatic cancer epidemiology: understanding the role of lifestyle and inherited risk factors

Pancreatic cancer is a leading cause of cancer death worldwide and its global burden has more than doubled over the past 25 years. The highest incidence regions for pancreatic cancer include North America, Europe and Australia, and although much of this increase is due to ageing worldwide populations, there are key modifiable risk factors for pancreatic cancer such as cigarette smoking, obesity, diabetes and alcohol intake. The prevalence of these risk factors is increasing in many global regions, resulting in increasing age-adjusted incidence rates for pancreatic cancer, but the relative contribution from these risk factors varies globally due to variation in the underlying prevalence and prevention strategies. Inherited genetic factors, although not directly modifiable, are an important component of pancreatic cancer risk, and include pathogenic variants in hereditary cancer genes, genes associated with hereditary pancreatitis, as well as common variants identified in genome-wide association studies. Identification of the genetic changes that underlie pancreatic cancer not only provides insight into the aetiology of this cancer but also provides an opportunity to guide early detection strategies. The goal of this Review is to provide an up-to-date overview of the established modifiable and inherited risk factors for pancreatic cancer.

Pancreatic Cancer Exposome Profile to Aid Early Detection and Inform Prevention Strategies

Pancreatic cancer (PCa) is associated with a poor prognosis and high mortality rate. The causes of PCa are not fully elucidated yet, although certain exposome factors have been identified. The exposome is defined as the sum of all environmental factors influencing the occurrence of a disease during a life span. The development of an exposome approach for PCa has the potential to discover new disease-associated factors to better understand the carcinogenesis of PCa and help with early detection strategies. Our systematic review of the literature identified several exposome factors that have been associated with PCa alone and in combination with other exposures. A potential inflammatory signature has been observed among the interaction of several exposures (i.e., smoking, alcohol consumption, diabetes mellitus, obesity, and inflammatory markers) that further increases the incidence and progression of PCa. A large number of exposures have been identified such as genetic, hormonal, microorganism infections and immune responses that warrant further investigation. Future early detection strategies should utilize this information to assess individuals' risk for PCa.

Increased Regulatory T Cells and Decreased Myeloid-Derived Suppressor Cells Induced by High CCL17 Levels May Account for Normal Incidence of Cancers among Patients with Atopic Dermatitis

The incidence of cancers in atopic dermatitis (AD) is not increased, although the Th2-dominant environment is known to downregulate tumor immunity. To gain mechanistic insights regarding tumor immunity in AD, we utilized CCL17 transgenic (TG) mice overexpressing CCL17, which is a key chemokine in AD. Tumor formation and lung metastasis were accelerated in CCL17 TG mice when melanoma cells were injected subcutaneously or intravenously. Flow cytometric analysis showed increases in regulatory T cells (Tregs) in lymph nodes in CCL17 TG mice with high mRNA levels of IL-10 and Foxp3 in tumors, suggesting that Tregs attenuated tumor immunity. The frequency of myeloid-derived suppressor cells (MDSCs), however, was significantly decreased in tumors of CCL17 TG mice, suggesting that decreased MDSCs might promote tumor immunity. Expression of CXCL17, a chemoattractant of MDSCs, was decreased in tumors of CCL17 TG mice. Depletion of Tregs by the anti-CD25 antibody markedly reduced tumor volumes in CCL17 TG mice, suggesting that tumor immunity was accelerated by the decrease in MDSCs in the absence of Tregs. Thus, CCL17 attenuates tumor immunity by increasing Tregs and Th2 cells, while it decreases MDSCs through reductions in CXCL17, which may work as a “safety-net” to reduce the risk of malignant tumors in the Th2-dominant environment.

Associations between Genetically Predicted Blood Protein Biomarkers and Pancreatic Cancer Risk

BACKGROUND

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, with few known risk factors and biomarkers. Several blood protein biomarkers have been linked to PDAC in previous studies, but these studies have assessed only a limited number of biomarkers, usually in small samples. In this study, we evaluated associations of circulating protein levels and PDAC risk using genetic instruments.

METHODS

To identify novel circulating protein biomarkers of PDAC, we studied 8,280 cases and 6,728 controls of European descent from the Pancreatic Cancer Cohort Consortium and the Pancreatic Cancer Case-Control Consortium, using genetic instruments of protein quantitative trait loci.

RESULTS

We observed associations between predicted concentrations of 38 proteins and PDAC risk at an FDR of < 0.05, including 23 of those proteins that showed an association even after Bonferroni correction. These include the protein encoded by ABO, which has been implicated as a potential target gene of PDAC risk variant. Eight of the identified proteins (LMA2L, TM11D, IP-10, ADH1B, STOM, TENC1, DOCK9, and CRBB2) were associated with PDAC risk after adjusting for previously reported PDAC risk variants (OR ranged from 0.79 to 1.52). Pathway enrichment analysis showed that the encoding genes for implicated proteins were significantly enriched in cancer-related pathways, such as STAT3 and IL15 production.

CONCLUSIONS

We identified 38 candidates of protein biomarkers for PDAC risk.

IMPACT

This study identifies novel protein biomarker candidates for PDAC, which if validated by additional studies, may contribute to the etiologic understanding of PDAC development.

Current status and perspectives regarding the association between allergic disorders and cancer

While activation of immune system may lead to a lower risk of some diseases, it has been shown that a history of atopic allergic disorders such as asthma, hay fever, eczema, and food allergies could be related to several types of cancer. However, the evidence is not entirely conclusive. Two proposals suggest a possible mechanism for the association between allergic disorders and cancers: immune surveillance and the antigenic stimulation. The association of allergy and cancer may vary by cancer site and the type of exposure. The aim of current review was to summarize the current knowledge of the association between allergic diseases and the risk of cancers with particular emphasis on case-controls and cohort studies to estimate the cancer risk associated with allergy.

Validation of genome-wide association study-identified single nucleotide polymorphisms in a case-control study of pancreatic cancer from Taiwan

Background

Due to differences in genetic background, it is unclear whether the genetic loci identified by the previous genome-wide association studies (GWAS) of pancreatic cancer also play significant roles in the development of pancreatic cancer among the Taiwanese population.

Methods

This study aimed to validate the 25 pancreatic cancer GWAS-identified single nucleotide polymorphisms (SNPs) in a case-control study (278 cases and 658 controls) of pancreatic cancer conducted in Taiwan. Statistical analyses were conducted to determine the associations between the GWAS-identified SNPs and pancreatic cancer risk. Gene-environment interaction analysis was conducted to evaluate the interactions between SNPs and environmental factors on pancreatic cancer risk.

Results

Among the 25 GWAS-identified SNPs, 7 (rs2816938 (~ 11 kb upstream of NR5A2), rs10094872 (~ 28 kb upstream of MYC), rs9581943 (200 bp upstream of PDX1) and 4 chromosome 13q22.1 SNPs: rs4885093, rs9573163, rs9543325, rs9573166) showed a statistically significant association with pancreatic cancer risk in the current study. Additional analyses showed two significant gene-environment interactions (between poor oral hygiene and NR5A2 rs2816938 and between obesity and PDX1 rs9581943) on the risk of pancreatic cancer.

Conclusions

The current study confirmed the associations between 7 of the 25 GWAS-identified SNPs and pancreatic risk among the Taiwanese population.

Furthermore, pancreatic cancer was jointly influenced by lifestyle and medical factors, genetic polymorphisms, and gene-environment interaction. Additional GWAS is needed to determine the genetic polymorphisms that are more relevant to the pancreatic cancer cases occurring in Taiwan.

Serum Immunoglobulin G Is Associated With Decreased Risk of Pancreatic Cancer in the Swedish AMORIS Study

Background: Emerging evidence points to potential roles of the humoral immune responses in the development of pancreatic cancer. Epidemiological studies have suggested involvement of viral and bacterial infections in pancreatic carcinogenesis. Experimental studies have reported high expression levels of antigens in pancreatic cancer cells. Therefore, we aimed to investigate the role of different components of humoral immunity in the context of pancreatic cancer. We evaluated associations between pre-diagnostic serum markers of the overall humoral immune system [immunoglobulin A (IgA), immunoglobulin G (IgG) and immunoglobulin M (IgM)], and the risk of pancreatic cancer in the Swedish Apolipoprotein-related MORtality RISk (AMORIS) study.

Methods: We selected all participants (≥20 years old) with baseline measurements of IgA, IgG or IgM (n = 41,900, 136,221, and 29,919, respectively). Participants were excluded if they had a history of chronic pancreatitis and individuals were free from pancreatic cancer at baseline. Multivariate Cox proportional hazards regression was used to estimate risk of pancreatic cancer for medical cut-offs of IgA, IgG, and IgM.

Results: Compared to the reference level of 6.10–14.99 g/L, risk of pancreatic cancer was elevated among those with IgG levels <6.10 g/L [HR: 1.69 (95% CI 0.99–2.87)], and an inverse association was observed among those with IgG levels ≥15.00 g/L [0.82 (95% CI 0.64–1.05); Ptrend = 0.027]. The association appeared to be stronger for women than men [HR: 0.64 (95% CI 0.43–0.97) and 0.95 (95% CI 0.69–1.29), respectively]. No associations were observed with IgA or IgM.

Conclusion: An inverse association was observed between pre-diagnostic serum levels of IgG and risk of pancreatic cancer. Our findings highlight the need to further investigate the role of immune response in pancreatic cancer etiology.

Upregulation of histamine receptor H1 promotes tumor progression and contributes to poor prognosis in hepatocellular carcinoma

H1 histamine receptor (H1HR) belongs to the family of rhodopsin-like G-protein-coupled receptors. Recent studies have shown that H1HR expression is increased in several types of cancer. However, its functional roles in tumor progression remain largely unknown, especially in hepatocellular carcinoma (HCC). We found that H1HR is frequently unregulated in HCC, which is significantly associated with both recurrence-free survival and overall survival in HCC patients. Functional experiments revealed that H1HR promoted both the growth and metastasis of HCC cells by inducing cell cycle progression, formation of lamellipodia, production of matrix metalloproteinase 2, and suppression of cell apoptosis. Activation of cyclic adenosine monophosphate-dependent protein kinase A was found to be involved in H1HR-mediated HCC cell growth and metastasis. In addition, we found that overexpression of H1HR was mainly due to the downregulation of miR-940 in HCC cells. Moreover, the H1HR inhibitor terfenadine significantly suppressed tumor growth and metastasis in an HCC xenograft nude mice model. Our findings demonstrate that H1HR plays a critical role in the growth and metastasis of HCC cells, which provides experimental evidence supporting H1HR as a potential drug target for the treatment of HCC.

Environmental Risk Factors of Pancreatic Cancer

Despite the advancement in medical knowledge that has improved the survival rate of many cancers, the survival rate of pancreatic cancer has remained dismal with a five-year survival rate of only 9%. The poor survival of pancreatic cancer emphasizes the urgent need to identify the causes or the risk factors of pancreatic cancer in order to establish effective preventive strategies. This review summarizes the current evidence regarding the environmental (non-genetic, including lifestyle, and clinical factors) risk factors of pancreatic cancer. Based on the current evidence, the established risk factors of pancreatic cancer are cigarette smoking, chronic diabetes, and obesity. Other strong risk factors include low consumption of fruits and vegetables, excess consumption of alcohol, poor oral hygiene, and the lack of allergy history. In the future, more studies are needed to identify additional risk factors of pancreatic cancer, especially the modifiable risk factors that could be included in a public health campaign to educate the public in order to reduce the incidence of pancreatic cancer.

Allergies and Asthma in Relation to Cancer Risk

BACKGROUND

Allergies and asthma, conditions commonly characterized by immunoglobulin E-mediated atopic reactions, may decrease cancer risk via increases in immunosurveillance, but may increase risk due to persistent immune stimulation. Associations between allergies and asthma and cancer risk remain unclear, and it is unknown whether associations vary by race/ethnicity.

METHODS

We evaluated these associations in the Southern Community Cohort Study. At baseline (2002-2009), 64,170 participants were queried on history of allergies and asthma; participants were followed through 2011, during which time 3,628 incident, invasive cancers were identified, including 667 lung cancers, 539 breast cancers, and 529 prostate cancers. Cox proportional hazards regression was used to estimate multivariable-adjusted HRs and 95% confidence intervals (CI).

RESULTS

Neither allergies nor asthma was associated with risk of developing invasive cancer overall. Asthma was associated with increased lung cancer risk (HR, 1.25; 95% CI, 1.00-1.57), with no variation by race/ethnicity (P _interaction = 0.84). Conversely, history of allergies was associated with decreased lung cancer risk (HR, 0.80; 95% CI, 0.65-1.00), with an inverse association observed among non-Hispanic whites (HR, 0.65; 95% CI, 0.45-0.94) but not non-Hispanic blacks (HR, 0.95; 95% CI, 0.73-1.25; P _interaction = 0.10). No statistically significant associations were observed for risk of breast or prostate cancers, overall or by race/ethnicity.

CONCLUSIONS

No associations were observed for risk of overall cancer, breast cancer, or prostate cancer. While asthma was associated with increased lung cancer risk, history of allergies was associated with decreased risk, an association driven by an inverse association among non-Hispanic whites.

IMPACT

Associations pertaining to lung cancer merit follow up in a large, diverse study.

Allergies and the Subsequent Risk of Cancer among Elderly Adults in the United States

BACKGROUND

Allergic conditions may prevent some cancers by promoting immune surveillance. We examined associations of allergic rhinitis, asthma, and eczema with cancer risk among elderly Americans.

METHODS

We used Surveillance Epidemiology and End Results (SEER)-Medicare linked data to perform a case-control study. Cases were individuals with first cancer diagnosed in SEER registries (1992-2013, ages 66-99; N = 1,744,575). Cancer-free controls (N = 100,000) were randomly selected from Medicare and matched on sex, age, and selection year. Allergic conditions were identified using Medicare claims, and logistic regression was used to estimate adjusted ORs (aOR) with significance gauged with a Bonferroni P cutoff (P < 0.00034).

RESULTS

Allergic rhinitis, asthma, and eczema were present in 8.40%, 3.45%, and 0.78% of controls, respectively. For allergic rhinitis, strong inverse associations (aORs, 0.66-0.79) were observed for cancers of the hypopharynx, esophagus (squamous cell), cervix, tonsil/oropharynx, and vagina/vulva. More modest but significant inverse associations were noted for cancers of the esophagus (adenocarcinoma), stomach, colon, rectosigmoid/rectum, liver, gallbladder, lung, uterus, bladder, and miscellaneous sites. Associations were stronger in analyses requiring a dispensed medication to confirm the presence of allergic rhinitis. Asthma was associated with reduced risk of liver cancer [aOR 0.82; 95% confidence interval (CI), 0.75-0.91], whereas eczema was associated with elevated risk of T-cell lymphoma (aOR, 4.12; 95% CI, 3.43-4.95).

CONCLUSIONS

Inverse associations with allergic rhinitis are present for multiple cancers and require etiologic investigation.

IMPACT

Understanding of mechanisms by which allergic conditions reduce cancer risk may advance cancer prevention and treatment.

Associations between Atopic Dermatitis and Risk of Gastric Cancer: A Nationwide Population-based Study

Background/Aims

Epidemiologic and clinical data indicate that allergies may be associated with reduced risks for several cancers; however, to date, only a few studies have examined the associations between allergies and gastric cancer. This study aimed to examine the associations between allergies and gastric cancer using a large population-based dataset.

Methods

This cross-sectional study obtained data from the Korea National Health and Nutrition Examination Survey between 2010 and 2014, involving a total of 24,089 participants. The associations between allergies and gastric cancer were analyzed using univariable and multivariable logistic regression analyses with complex sampling, while adjusting for confounding factors that included age, sex, body mass index, smoking status, alcohol intake, and level of education.

Results

Multivariable logistic regression analyses that were adjusted for the potential confounders determined that a history of allergic diseases tended to be associated with reduced risk of gastric cancer; however, this relationship was not statistically significant (any allergy: odds ratio [OR], 0.62; 95% confidence interval [CI], 0.34-1.12; atopic dermatitis: OR, 0.34; 95% CI, 0.50-1.72; allergic rhinitis: OR, 0.71; 95% CI, 0.34-1.46; asthma: OR, 0.44; 95% CI, 0.15-1.29). Multivariable analysis showed that a history of atopic dermatitis was associated with reduced risk of gastric cancer in men (OR, 0.16; 95% CI, 0.03-0.75).

Conclusions

This findings of this study suggest that individuals with allergies tend to have a reduced risk of gastric cancer, without a statistically significant association. Furthermore, atopic dermatitis was associated with reduced risk of gastric cancer, particularly in men.

Atopic allergic conditions and pancreatic cancer risk: Results from the Multiethnic Cohort Study

Previous case-control studies have suggested that atopic allergic conditions (AACs) are inversely associated with pancreatic cancer, but this relationship has not been supported in many prospective settings. In this study, we investigated the influence of AACs (asthma, hay fever, or allergy) and the treatment of these conditions on pancreatic cancer risk among participants of the Multiethnic Cohort Study (MEC). AACs and antihistamine use were assessed via a baseline questionnaire when participants joined the MEC in 1993-1996. Risk ratios (RRs) and 95% confidence intervals (CIs) for pancreatic cancer incidence by AACs and antihistamines were calculated using Cox regression, adjusting for age, sex, ethnicity, education, smoking status, family history of pancreatic cancer, body mass index, diabetes, and alcohol intake. We further evaluated associations among subgroups defined by age, sex, ethnicity, follow-up time, and known pancreatic cancer risk factors. During an average 16-year follow-up, 1,455 incident cases of pancreatic cancer were identified among 187,226 white, African American, Latino, Japanese American, and Native Hawaiian men and women. AACs (RR 1.00, 95% CI 0.88-1.12) and antihistamines (RR 0.92, 95% CI 0.78-1.07) were not clearly associated with pancreatic cancer incidence. While these associations were also null for most subgroups, we did observe protective associations of AACs (RR 0.74, 95% CI 0.56-0.98) and antihistamines (RR 0.66, 95% CI 0.45-0.96) among the oldest participants (70+). Our results, in agreement with past prospective studies, suggest that AACs are not associated with pancreatic cancer in general, but the observed protective associations among the oldest age group may warrant future investigation.

Impact of Selenium Supplementation in Neutropenia and Immunoglobulin Production in Childhood Cancer Patients

Essential to human health, selenium (Se) has enzymatic functions of fundamental importance to human biology due to its effects on DNA damage repair, its antioxidant properties, and cancer prevention. The best studied relationships between Se and the immune system is its role in the functions of neutrophils and of lymphocytes. Despite these observations, it is not yet clear by which mechanism Se is able to modify the immune status. This was a double-blind, crossover study: Group 1 received Se and Group 2 received placebo (30 days). After this, Group 1 received placebo and Group 2 received Se (30 days). Every 30 days, blood samples were collected for white blood cell count, red blood cell count, and Ig level measurement (IgA, IgG, IgE, IgM). Of the 36 patients, 17 were suffering from leukemia/lymphomas (LL) and 19 from solid tumors (ST). In the ST group's leukogram, a significant increase in neutrophils was observed after Se usage (P = .0192). During the analyzed period, Se minimized the triggering of neutropenia cases in both groups. IgA and IgG levels in ST patients were significantly higher than those identified in LL patients after Se usage (P = .0051 and P = .0055). For IgA, a significant increase in its production, after Se usage, was observed in the ST group when compared to the LL (P = .0011). The same did not occur to the IgM and IgE immunoglobulins. In our study, the supplementation with Se reduced the neutropenic cases (LL and ST patients) and reduced IgG and IgA levels in LL and increased in ST group.

Atopy and Specific Cancer Sites: a Review of Epidemiological Studies

Mounting evidence appears to link asthma and atopy to cancer susceptibility. This review presents and discusses published epidemiological studies on the association between site-specific cancers and atopy. PubMed was searched electronically for publications between 1995 and 2015, and cited references were researched manually. Quantitative studies relating to atopy, allergy, or asthma and cancer were identified and tabulated. Despite many exposure-related limitations, patterns in the studies were observed. Asthma, specifically, has been observed to be a risk factor for lung cancer. A protective effect of atopic diseases against pancreatic cancer has been shown consistently in case-control studies but not in cohort studies. Allergy of any type appears to be protective against glioma and adult acute lymphoblastic leukemia. Most studies on atopic diseases and non-Hodgkin lymphoma or colorectal cancer reported an inverse association. The other sites identified had varying and non-significant outcomes. Further research should be dedicated to carefully defined exposure assessments of "atopy" as well as the biological plausibility in the association between atopic diseases and cancer.

Reduced risk of pancreatic cancer associated with asthma and nasal allergies

OBJECTIVE

Studies indicate an inverse association between ductal adenocarcinoma of the pancreas (PDAC) and nasal allergies. However, controversial findings are reported for the association with asthma. Understanding PDAC risk factors will help us to implement appropriate strategies to prevent, treat and diagnose this cancer. This study assessed and characterised the association between PDAC and asthma and corroborated existing reports regarding the association between allergies and PDAC risk.

DESIGN

Information about asthma and allergies was collated from 1297 PDAC cases and 1024 controls included in the PanGenEU case-control study. Associations between PDAC and atopic diseases were studied using multilevel logistic regression analysis. Meta-analyses of association studies on these diseases and PDAC risk were performed applying random-effects model.

RESULTS

Asthma was associated with lower risk of PDAC (OR 0.64, 95% CI 0.47 to 0.88), particularly long-standing asthma (>=17 years, OR 0.39, 95% CI 0.24 to 0.65). Meta-analysis of 10 case-control studies sustained our results (metaOR 0.73, 95% CI 0.59 to 0.89). Nasal allergies and related symptoms were associated with lower risk of PDAC (OR 0.66, 95% CI 0.52 to 0.83 and OR 0.59, 95% CI 0.46 to 0.77, respectively). These results were supported by a meta-analysis of nasal allergy studies (metaOR 0.6, 95% CI 0.5 to 0.72). Skin allergies were not associated with PDAC risk.

CONCLUSIONS

This study shows a consistent inverse association between PDAC and asthma and nasal allergies, supporting the notion that atopic diseases are associated with reduced cancer risk. These results point to the involvement of immune and/or inflammatory factors that may either foster or restrain pancreas carcinogenesis warranting further research to understand the molecular mechanisms driving this association.

Environmental risk factors for pancreatic cancer: an update

Pancreatic cancer (PC) is one of the most aggressive diseases. Only 10 % of all PC cases are thought to be due to genetic factors. Here, we analyzed the most recently published case-control association studies, meta-analyses, and cohort studies with the aim to summarize the main environmental factors that could have a role in PC. Among the most dangerous agents involved in the initiation phase, there are the inhalation of cigarette smoke, and the exposure to mutagenic nitrosamines, organ-chlorinated compounds, heavy metals, and ionizing radiations. Moreover, pancreatitis, high doses of alcohol drinking, the body microbial infections, obesity, diabetes, gallstones and/or cholecystectomy, and the accumulation of asbestos fibers seem to play a crucial role in the progression of the disease. However, some of these agents act both as initiators and promoters in pancreatic acinar cells. Protective agents include dietary flavonoids, marine omega-3, vitamin D, fruit, vegetables, and the habit of regular physical activity. The identification of the factors involved in PC initiation and progression could be of help in establishing novel therapeutic approaches by targeting the molecular signaling pathways responsive to these stimuli. Moreover, the identification of these factors could facilitate the development of strategies for an early diagnosis or measures of risk reduction for high-risk people.

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.

Asthma and Risk of Prostate Cancer: A Population-Based Case-Cohort Study in Taiwan

Several epidemiologic studies in Western countries have examined the association between asthma and prostate cancer risk, but the results have been inconclusive. We investigated this association in a large, nationwide, population-based case-cohort study. Using the Taiwan National Health Insurance Research Database from 1997 to 2008, we collected data from 12,372 men, including 4124 with asthma and 8248 age-, residence-, and insurance premium-matched control subjects, who were never diagnosed with asthma. Competing risk-adjusted Cox proportional hazards regression was used to calculate the hazard ratios (HRs) and 95% confidence interval (CI) for determining the association between prostate cancer and asthma. During a mean follow-up of 5.05 years (standard deviation, 2.10), there were 74 cases of prostate cancer. The incidence of prostate cancer was 163.0/100,000 person-years (95% CI: 113.0-228.0) in the asthma patients. Asthma was significantly associated with prostate cancer (HR: 2.36; 95% CI: 1.22-4.57; P = 0.011) after adjusting for age, residential area, insurance premium, hypertriglyceridemia, hypertension, diabetes mellitus, chronic obstructive pulmonary disease, duration of hospitalization, and mortality. In the subgroup analysis, independent risk factors for prostate cancer among men with asthma were age (HR: 1.09; 95% CI: 1.05-1.21; P < 0.001) and hypertension (HR: 2.75; 95% CI: 1.24-7.80; P = 0.047). The results of our study suggest that men with asthma have an increased risk of prostate cancer.

The necessity of an observational study on the interactions between allergic history and citrus fruit intake for the prevention of pancreatic cancer

While the main product of Jeju Island is citrus fruit and the prevalence of atopic dermatitis among the students who live there is relatively high, the incidence of pancreatic cancer is lowest in Korea. Systematic reviews reporting allergic history and intake of citrus fruit as protective factors against pancreatic cancer (PCC) were published in 2005 and 2008, respectively. Although there were discrepancies in the results of the subgroup analyses between case-control and cohort studies, it is necessary to evaluate an interaction effect between allergic history and intake of citrus fruits on PCC risk.

Association between Variants in Atopy-Related Immunologic Candidate Genes and Pancreatic Cancer Risk

Background

Many epidemiology studies report that atopic conditions such as allergies are associated with reduced pancreas cancer risk. The reason for this relationship is not yet understood. This is the first study to comprehensively evaluate the association between variants in atopy-related candidate genes and pancreatic cancer risk.

Methods

A population-based case-control study of pancreas cancer cases diagnosed during 2011-2012 (via Ontario Cancer Registry), and controls recruited using random digit dialing utilized DNA from 179 cases and 566 controls. Following an exhaustive literature review, SNPs in 180 candidate genes were pre-screened using dbGaP pancreas cancer GWAS data; 147 SNPs in 56 allergy-related immunologic genes were retained and genotyped. Logistic regression was used to estimate age-adjusted odd ratio (AOR) for each variant and false discovery rate was used to adjust Wald p-values for multiple testing. Subsequently, a risk allele score was derived based on statistically significant variants.

Results

18 SNPs in 14 candidate genes (CSF2, DENND1B, DPP10, FLG, IL13, IL13RA2, LRP1B, NOD1, NPSR1, ORMDL3, RORA, STAT4, TLR6, TRA) were significantly associated with pancreas cancer risk. After adjustment for multiple comparisons, two LRP1B SNPs remained statistically significant; for example, LRP1B rs1449477 (AA vs. CC: AOR=0.37, 95% CI: 0.22-0.62; p (adjusted)=0.04). Furthermore, the risk allele score was associated with a significant reduction in pancreas cancer risk (p=0.0007).

Conclusions

Preliminary findings suggest certain atopy-related variants may be associated with pancreas cancer risk. Further studies are needed to replicate this, and to elucidate the biology behind the growing body of epidemiologic evidence suggesting allergies may reduce pancreatic cancer risk.

Analysis of the involvement of cytokines in allergy and breast cancer association

AIM OF THE STUDY

The existence of a correlation between allergy disorders and cancer diseases has been confirmed by several epidemiological studies. Although the molecular mechanism involved in this phenomenon remains unknown, there are data indicating that certain cytokines, engaged in allergic processes, have antineoplastic activities. The aim of the present study was to explore the association between advanced breast cancer and allergic state on the molecular level.

MATERIAL AND METHODS

We determined and compared the mRNA and protein expression of interleukin-1β (IL-1β), IL-4, IL-6, and interferon-γ (IFN-γ), cytokines known for antitumor properties, in the blood of advanced breast cancer patients and individuals with allergic diseases related to type 2 response. In addition, we performed an in vitro assay of reactivity of peripheral blood mononuclear cells after exogenous antigen stimulation. As a preliminary to molecular analysis we conducted a questionnaire study concerning the incidence of allergy among breast cancer patients and healthy subjects without malignancy.

RESULTS

The results of the survey study revealed a negative relation between breast cancer and allergy prevalence. Subsequent molecular analysis, however, did not show statistically significant differences in cytokines mRNA and protein expression levels between allergic patients and those with malignancy. The in vitro reactivity test also did not reveal marked differences between IL-1β, IL-4 and IL-6 production after PBMC triggering with exogenous antigen.

CONCLUSIONS

We concluded that the studied cytokines (IL-1β, IL-4, IL-6, and IFN-γ) are not engaged in breast cancer-allergy negative relation.

Dietary inflammatory index and risk of pancreatic cancer in an Italian case-control study

Previous studies have shown that various dietary components may be implicated in the aetiology of pancreatic cancer. However, the possible relationship between diet-related inflammation and the risk of pancreatic cancer has not yet been investigated. We examined the ability of a newly developed literature-derived dietary inflammatory index (DII) to predict the risk of pancreatic cancer in a case-control study conducted in Italy between 1991 and 2008. This included 326 incident cases and 652 controls admitted to the major teaching and general hospitals for non-neoplastic diseases, frequency-matched to cases by study centre, sex and age. The DII was computed based on dietary intake assessed using a validated and reproducible seventy-eight-item FFQ. Logistic regression models were used to estimate multivariable OR adjusted for age, sex, study centre, education, BMI, smoking status, alcohol drinking and history of diabetes. Energy adjustment was performed using the residual method. Subjects with higher DII scores (i.e., representing a more pro-inflammatory diet) had a higher risk of pancreatic cancer, with the DII being used as both a continuous variable (ORcontinuous 1.24, 95% CI 1.11, 1.38) and a categorical variable (i.e., compared with the subjects in the lowest quintile of the DII, those in the second, third, fourth and fifth quintiles had, respectively, OR(quintile2 v. 1) 1.70, 95% CI 1.02, 2.80; OR(quintile3 v. 1) 1.91, 95% CI 1.16, 3.16; OR(quintile4 v. 1) 1.98, 95% CI 1.20, 3.27; OR(quintile5 v. 1) 2.48, 95% CI 1.50, 4.10; P trend= 0.0015). These data suggest that a pro-inflammatory diet increases the risk of pancreatic cancer.

Risk factors for pancreatic cancer: a summary review of meta-analytical studies

BACKGROUND

The aetiology of pancreatic cancer (PC) has been extensively studied and is the subject of numerous meta-analyses and pooled analyses. We have summarized results from these pooled and meta-analytical studies to estimate the fraction of PCs attributable to each of the identified risk factors.

METHODS

Using a comprehensive strategy, we retrieved 117 meta-analytical or pooled reports dealing with the association between specific risk factors and PC risk. We combined estimates of relative risk and estimates of exposure to calculate the fraction of PCs caused or prevented by a particular exposure.

RESULTS

Tobacco smoking ('strong' evidence) and Helicobacter pylori infection ('moderate' evidence) are the major risk factors associated with PC, with respective estimated population attributable fractions of 11-32% and 4-25%. The major protective factors are history of allergy ('strong' evidence) and increasing fruit or folate intake ('moderate' evidence), with respective population preventable fractions of 3-7% and 0-12%.

CONCLUSIONS

We summarized results of 117 meta-analytical or pooled data reports dealing with 37 aetiological exposures, to obtain robust information about the suspected causes of PC. By combining these estimates with their prevalences in the population, we calculated population attributable or population preventable fractions. About two-thirds of the major risk factors associated with PC are potentially modifiable, affording a unique opportunity for preventing one of our deadliest cancers.

Asthma, allergy and the risk of prostate cancer: results from the Montreal PROtEuS study

BACKGROUND

The few previous studies examining the association between asthma or allergy and prostate cancer (PCa) risk were inconclusive. This study aimed to evaluate these associations, and to explore in details the possible influence of current versus former allergic condition, age at onset, time since onset, and duration of each allergic condition.

METHODS

Detailed information on self-reported asthma and allergy was collected in the context of a large population-based case-control study conducted in Montreal, Canada. Study subjects included 1936 cases, diagnosed between 2005 and 2009, and 1995 population controls. Unconditional multivariate logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (CI) adjusting for age, ancestry and familial history of prostate cancer.

RESULTS

The ORs were 1.11 (95% CI: 0.89-1.40) and 0.98 (95% CI: 0.84-1.14) for ever reporting of asthma and allergy, respectively. These ORs did not substantially vary according to status (former or current), age at onset, time since onset, and duration of each allergic condition. PCa screening was not associated with allergic diseases reporting.

CONCLUSIONS

Overall, our findings are in line with the absence of an association between a history of asthma or allergy, and PCa risk.

Drug allergy and the risk of lymph node metastasis in rectal cancer

Background

Previous epidemiologic studies have reported that a history of allergy is associated with reduced risk of colorectal cancer and other malignancies. However, no information is available for the association between allergy and the risk of lymph node metastasis. Our study was designed to determine this association in rectal cancer.

Methods

Patients who were treated at our hospital in the period from January 2003 to June 2011, and with a pathologically hospital discharge diagnosis of rectal adencarcinoma, were included. The clinical, laboratory, and pathologic parameters were analyzed. A multivariate logistic regression model was used to determine the association. Moreover, for type of allergic drug, sub-group analysis was performed.

Results

469 patients were included, including 231 with pathological lymph node metastasis (pLNM) (49.3%) and 238 without pLNM. Univariate analysis showed, compared with patients without pLNM, patients with pLNM had a younger age (60.6±12.8 yr vs. 63.6±12.2 yr, P = 0.012), a lower percentage of drug allergy (8.7% vs. 16.0%, P = 0.016), an increased CEA (median/interquartile-range 5.40/2.40–13.95 vs. 3.50/2.08–8.67, P = 0.009), and a lower serum sodium (141±3.1 mmol/L vs. 142±2.9 mmol/L, P = 0.028). Multivariate analysis showed that drug allergy was associated with a reduced risk of pLNM (OR = 0.553; 95% CI, 0.308–0.994; P = 0.048). In addition, our results showed that: (1) for tumor classification, patients with drug allergy had a higher percentage of group patients with pT1/pT2; and (2) for type of allergic drug, this inverse association was found for penicillins, not for other allergic drugs.

Conclusion

Drug allergy is associated with a reduced risk of pLNM in rectal cancer.

Serum immunoglobulin e and risk of pancreatic cancer in the prostate, lung, colorectal, and ovarian cancer screening trial

Epidemiologic studies have consistently found that self-reported allergies are associated with reduced risk of pancreatic cancer. Our aim was to prospectively assess the relationship between serum immunoglobulin E (IgE), a marker of allergy, and risk. This nested case-control study within the Prostate, Lung, Colorectal, and Ovarian Cancer Screening Trial (PLCO) included subjects enrolled in 1994 to 2001 and followed through 2010. There were 283 cases of pancreatic cancer and 544 controls matched on age, gender, race, and calendar date of blood draw. Using the ImmunoCAP system, we measured total IgE (normal, borderline, elevated), IgE to respiratory allergens, and IgE to food allergens (negative or positive) in serum collected at baseline. Odds ratios (OR) and 95% confidence intervals (CI) were estimated using conditional logistic regression. We assessed interactions with age, gender, smoking, body mass index, and time between randomization and case diagnosis. Overall, there was no association between the IgE measures and risk. We found a statistically significant interaction by baseline age: in those aged ≥65 years, elevated risks were observed for borderline total IgE (OR, 1.43; 95% CI, 0.88-2.32) and elevated total IgE (OR, 1.98; 95% CI, 1.16-3.37) and positive IgE to food allergens (OR, 2.83; 95% CI, 1.29-6.20); among participants <65 years, ORs were <1. Other interactions were not statistically significant. The reduced risk of pancreatic cancer associated with self-reported allergies is not reflected in serum IgE.

Association between allergies and risk of pancreatic cancer

BACKGROUND

Less than 10% of pancreatic cancer cases survive 5 years, yet its etiology is not well understood. Studies suggest allergies are associated with reduced pancreatic cancer risk. Our study collected additional information on allergies (including skin prick test results and differentiation of allergic/nonallergic asthma), and is the first to assess possible confounding by allergy medications.

METHODS

A population-based case-control study was designed to comprehensively assess the association between allergy and pancreatic cancer risk. Pancreas cancer cases were diagnosed during 2011 to 2012, and identified through the Ontario Cancer Registry (345 cases). Population-based controls were identified using random digit dialing and age/sex frequency matched to cases (1,285 controls). Questionnaires collected lifetime allergy history (type of allergy, age at onset, skin prick testing results), allergy medications, and established pancreas cancer risk factors. Logistic regression was used to estimate odd ratios and test potential confounders, including allergy medications.

RESULTS

Hay fever was associated with a significant reduction in pancreatic cancer risk [AOR = 0.68; 95% confidence intervals (CI), 0.52-0.89], and reduction was greatest for those whose skin prick test was positive for hay fever allergens. No particular patterns were observed as regards age at onset and duration of allergy. Positive dust/mold allergy skin prick test and animal allergies were associated with a statistically significant reduced pancreatic cancer risk; AOR = 0.49; 95% CI, 0.31-0.78 and AOR = 0.68; 95% CI, 0.46-0.99, respectively. Asthma was not associated with pancreatic cancer risk.

CONCLUSIONS/IMPACT

These findings support the growing body of evidence that suggests certain allergies are associated with reduced pancreatic cancer risk.

Allergies and risk of pancreatic cancer: a pooled analysis from the Pancreatic Cancer Case-Control Consortium

In order to quantify the risk of pancreatic cancer associated with history of any allergy and specific allergies, to investigate differences in the association with risk according to age, gender, smoking status, or body mass index, and to study the influence of age at onset, we pooled data from 10 case-control studies. In total, there were 3,567 cases and 9,145 controls. Study-specific odds ratios and 95% confidence intervals were calculated by using unconditional logistic regression adjusted for age, gender, smoking status, and body mass index. Between-study heterogeneity was assessed by using the Cochran Q statistic. Study-specific odds ratios were pooled by using a random-effects model. The odds ratio for any allergy was 0.79 (95% confidence interval (CI): 0.62, 1.00) with heterogeneity among studies (P < 0.001). Heterogeneity was attributable to one study; with that study excluded, the pooled odds ratio was 0.73 (95% CI: 0.64, 0.84) (Pheterogeneity = 0.23). Hay fever (odds ratio = 0.74, 95% CI: 0.56, 0.96) and allergy to animals (odds ratio = 0.62, 95% CI: 0.41, 0.94) were related to lower risk, while there was no statistically significant association with other allergies or asthma. There were no major differences among subgroups defined by age, gender, smoking status, or body mass index. Older age at onset of allergies was slightly more protective than earlier age.

Association between allergies, asthma, and breast cancer risk among women in Ontario, Canada

PURPOSE

To investigate the association between allergies, asthma, and breast cancer risk in a large, population-based case-control study.

METHODS

Breast cancer cases (n = 3,101) were identified using the Ontario Cancer Registry and population controls (n = 3,471) through random digit dialing. Self-reported histories of allergies, hay fever, and asthma were collected by questionnaire. Logistic regression was used to assess associations between breast cancer risk and history of allergy/hay fever and asthma, with 16 possible confounders examined. Analyses were stratified by menopausal status.

RESULTS

A history of allergies or hay fever was associated with a small reduction in breast cancer risk [age-adjusted odds ratio (AOR) = 0.86, 95 % confidence interval (CI) 0.77-0.96] and did not differ by menopausal status. Asthma was not associated with breast cancer risk overall; however, among premenopausal women, asthma was associated with a reduced risk of breast cancer (AOR = 0.72, 95 % CI 0.54-0.97).

CONCLUSIONS

A history of allergies may be associated with a modest reduction in breast cancer risk. Asthma does not appear to be associated with breast cancer risk overall; however, asthma may be associated with reduced breast cancer risk among premenopausal women.

Allergies and risk of head and neck cancer: an original study plus meta-analysis

Background

Although the relationship between allergy and cancer has been investigated extensively, the role of allergy in head and neck cancer (HNC) appears less consistent. It is not clear whether allergies can independently influence the risk of HNC in the presence of known strong environmental risk factors, including consumption of alcohol, betel quid, and cigarette.

Methods

The current paper reports results from: 1) an original hospital-based case-control study, which included 252 incident cases of HNC and 236 controls frequency-matched to cases on sex and age; and 2) a meta-analysis combining the results of the current case-control study and 13 previously published studies (9 cohort studies with 727,569 subjects and 550 HNC outcomes and 5 case-control studies with 4,017 HNC cases and 10,928 controls).

Results

In the original case-control study, we observed a strong inverse association between allergies and HNC [odds ratio = 0.41, 95% confidence interval (CI): 0.27–0.62]. The meta-analysis also indicated a statistically significant inverse association between HNC and allergies [meta-relative risk (RR) = 0.76, 95% CI: 0.63–0.91], particularly strong for allergic rhinitis (meta-RR = 0.55, 95% CI: 0.40–0.76). In addition, the inverse association between allergies and HNC was observed only among men (meta-RR = 0.67, 95% CI: 0.54–0.84) but not among women (meta-RR = 0.98, 95% CI: 0.81–1.18).

Conclusions

These findings suggest that immunity plays an influential role in the risk of HNC. Future studies investigating immune biomarkers, including cytokine profiles and genetic polymorphisms, are warranted to further delineate the relationship between allergies and HNC. Understanding the relationship between allergies and HNC may help devise effective strategies to reduce and treat HNC.

A history of allergies is associated with reduced risk of oral squamous cell carcinoma

PURPOSE

A history of allergies is associated with a decreased risk of several types of cancers. Potential mechanisms include enhanced immune surveillance against tumor cells early in disease development and/or carcinogenic infectious agents. We tested whether allergies are inversely associated with oral squamous cell carcinoma (OSCC), accounting for factors that may modify the association, such as tumor site, stage, and HPV infection.

METHODS

We estimated odds ratios (OR) and 95 % confidence intervals (CI) for the association between allergy history (including different types of allergies) and OSCC, adjusted for potential confounders, among 400 cases and 613 controls. Analyses were also stratified by site, stage, and measures of HPV infection.

RESULTS

We observed a weak inverse association between history of any allergy and OSCC (OR = 0.81, 95 % CI 0.61-1.08). This association was present only for allergies to airborne allergens (dust/pollen/mold) (OR = 0.67; 95 % CI 0.48-0.93). The inverse associations with airborne allergies were slightly stronger for oropharyngeal SCC (OR = 0.56; 95 % CI 0.35-0.90) than for oral cavity SCC (OR = 0.71; 95 % CI 0.49-1.05) and present only for later-stage cancers (OR = 0.42; 95 % CI 0.26-0.66) as opposed to earlier-stage cancers (OR = 0.98; 95 % CI 0.66-1.46). Inverse associations were not particularly present or stronger among HPV-16-seropositive individuals or for HPV DNA-positive OSCC.

CONCLUSION

There is an inverse association between history of allergies to dust, pollen, or mold and OSCC. Whether the inverse association involves heightened immune surveillance, increased immune response to HPV or other antigen, or other carcinogenic mechanism remains to be determined in more definitive studies.

Loss of cutaneous TSLP-dependent immune responses skews the balance of inflammation from tumor protective to tumor promoting

Inflammation can promote or inhibit cancer progression. In this study we have addressed the role of the proinflammatory cytokine thymic stromal lymphopoietin (TSLP) during skin carcinogenesis. Using conditional loss- and gain-of-function mouse models for Notch and Wnt signaling, respectively, we demonstrate that TSLP-mediated inflammation protects against cutaneous carcinogenesis by acting directly on CD4 and CD8 T cells. Genetic ablation of TSLP receptor (TSLPR) perturbs T-cell-mediated protection and results in the accumulation of CD11b(+)Gr1(+) myeloid cells. These promote tumor growth by secreting Wnt ligands and augmenting β-catenin signaling in the neighboring epithelium. Epithelial specific ablation of β-catenin prevents both carcinogenesis and the accumulation of CD11b(+)Gr1(+) myeloid cells, suggesting tumor cells initiate a feed-forward loop that induces protumorigenic inflammation.

Elevated epidermal thymic stromal lymphopoietin levels establish an antitumor environment in the skin

Thymic Stromal Lymphopoietin (TSLP), a cytokine implicated in induction of T helper 2 (Th2)-mediated allergic inflammation, has recently been shown to stimulate solid tumor growth and metastasis. Conversely, studying mice with clonal loss of Notch signaling in their skin revealed that high levels of TSLP released by barrier-defective skin caused a severe inflammation, resulting in gradual elimination of Notch-deficient epidermal clones and resistance to skin tumorigenesis. We found CD4(+) T cells to be both required and sufficient to mediate these effects of TSLP. Importantly, TSLP overexpression in wild-type skin also caused resistance to tumorigenesis, confirming that TSLP functions as a tumor suppressor in the skin.

IgE and chemotherapy

The nexus of chemotherapeutic intervention and the immunomodulation of IgE-related phenomena are not well understood. The relationship bears importance in better understanding the causal and/or resultant effects of one on the other and their collective role in the management and sequelae of the cancer patient. This review discusses the relationship of chemotherapy on immunoglobulins with a focus on IgE and other related biological processes including hypersensitivity reactions and proposes models toward effective management of the cancer patient in this regard.