Hormonal factors and pancreatic cancer risk in women: The Malmö Diet and Cancer Study

Exploring the logic and conducting a comprehensive evaluation of AdipoRon-based adiponectin replacement therapy against hormone-related cancers-a systematic review

The potential benefits of adiponectin replacement therapy extend to numerous human diseases, with current research showing particular interest in its effectiveness against specific cancer forms, especially hormone-related. However, limitations in the pharmacological use of the intact protein have led to a focus on alternative options. AdipoRon is an extensively studied non-peptidic drug candidate for adiponectin replacement therapy. While researchers have explored the efficacy and therapeutic applications of AdipoRon in various disease conditions, their effects against cancer models advanced more, with no review regarding AdipoRon's efficacy against hormone-related cancers being published. The present systematic review aims to fill this gap. Preclinical evidence was compiled from PubMed, EMBASE, COCHRANE, and Google Scholar following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, and the manuscript's quality assessment was conducted using the Joanna Briggs Institute (JBI) Checklist Critical Appraisal Tool for Systematic Reviews' Quality. The included nine studies incorporated various cell and animal models of the pancreas, gynaecological system, and osteosarcoma cancers. AdipoRon demonstrated effectiveness against pancreatic cancer by activating p44/42 MAPK, mitochondrial dysfunction, and AMPK-mediated inhibition of ACC1. In gynaecological cancers, it exhibited promising anticancer effects through the activation of AMPK, potential inhibition of mTOR, and modulation of the SET1B/BOD1/AdipoR1 signaling cascade. Against osteosarcoma, AdipoRon worked by perturbing ERK1/2 signaling and reducing p70S6K phosphorylation. AdipoRon shows promise in preclinical studies, but human trials are crucial for clinical safety and effectiveness. Caution is needed due to potential off-target effects, especially in cancer therapy with multi-target approaches. Structural biology and computational methods can help predict these effects.

Meta-analysis: Risk of pancreatic cancer in patients with inflammatory bowel disease

BACKGROUND

Studies exploring the association between inflammatory bowel disease (IBD) and pancreatic cancer have reported inconsistent results.

AIMS

To provide a comprehensive overview of the risk of pancreatic cancer development in patients with IBD.

METHODS

We searched Embase, PubMed, Scopus and ProQuest from inception to 31 October 2023. We included population-based cohort studies examining the risk of incident pancreatic cancer in adult patients with IBD compared to the non-IBD population. We also retrieved Mendelian randomisation (MR) studies investigating the relationship of IBD with pancreatic cancer risk. We conducted random-effects meta-analyses and provided pooled relative risks (RRs) with 95% confidence intervals (CIs).

RESULTS

We included 13 studies. Among 11 cohort studies, the risk of developing pancreatic cancer increased by 79% in patients with IBD (RR = 1.79 [95% CI: 1.16-2.75]; I2 = 95.7%). Patients either with Crohn's disease (RR = 1.42 [95% CI: 1.24-1.63]) or ulcerative colitis (RR = 1.50 [95% CI: 1.17-1.92]) had increased risk (p for interaction = 0.72). The annual incidence of pancreatic cancer potentially attributable to IBD increased by 55 cases (95% CI: 17-103) per million. Two MR studies demonstrated that genetic liability to IBD was associated with an increased risk of pancreatic cancer.

CONCLUSIONS

Our results suggest a moderate increase in the risk of pancreatic cancer in patients with IBD, which may be further heightened by genetic predisposition to IBD. The increased risk of pancreatic cancer is probably similar in Crohn's disease and ulcerative colitis.

The Disproportionate Rise in Pancreatic Cancer in Younger Women Is Due to a Rise in Adenocarcinoma and Not Neuroendocrine Tumors: A Nationwide Time-Trend Analysis Using 2001-2018 United States Cancer Statistics Databases

In previous studies, a significant increase in the incidence of pancreatic cancer among younger women compared to men in the United States was noted. However, the specific histopathologic characteristics were not delineated. This population-based study aimed to assess whether this disproportionate rise in pancreatic cancer in younger women was contributed by pancreatic ductal adenocarcinoma (PDAC) or pancreatic neuroendocrine tumors (PanNET). The United States Cancer Statistics (USCS) database was used to identify patients with pancreatic cancer between 2001 and 2018. The results showed that, in younger adults, the incidence of PDAC has increased in women [average annual percentage change (AAPC) = 0.62%], while it has remained stable in men (AAPC = -0.09%). The PDAC incidence rate among women increased at a greater rate compared to men with a statistically significant difference in AAPC (p < 0.001), with neither identical nor parallel trends. In contrast, cases of PanNET did not demonstrate a statistically significant sex-specific AAPC difference. In conclusion, this study demonstrated that the dramatic increase in the incidence rate of PDAC explains the disproportionate rise in pancreatic cancer incidence in younger women. This prompts further prospective studies to investigate the underlying reasons for these sex-specific disparities in PDAC.

Burden of pancreatic cancer in older adults globally, regionally, and in 204 countries: 1990-2019 and projections to 2030

BACKGROUND

Global aging is increasing; however, the epidemiologic characteristics of pancreatic cancer in older adults have not been systematically studied.

METHODS

This study used data on pancreatic cancer in older adults from the Global Burden of Disease 2019 project. Temporal trends were measured using average annual percentage change and predicted using a Bayesian age-period-cohort model. In addition, the inequality slope index and the health concentration index scores were calculated to quantify the unequal distribution of the burden of pancreatic cancer in older adults.

RESULTS

Between 1990 and 2019, the number of pancreatic cancer deaths in older adults, age-standardized death rate (ASDR), disability-adjusted life years (DALYs), and age-standardized DALY rate increased globally. In 2019, ASDR and age-standardized DALY rate for pancreatic cancer in older adults were the highest in Southern Latin America, whereas the burden has grown the fastest over the past 30 years in the Caribbean. The burden is predominantly distributed among those aged 65 to 74 years, with males having a higher burden than that of females. The global proportion of pancreatic cancer deaths in older adults attributed to smoking, high fasting plasma glucose, and high body mass index were 21.7%, 10.3%, and 5.8%, respectively. Both absolute and relative cross-national inequalities declined over the past 30 years but remained at medium-high levels of relative inequality. Deaths from pancreatic cancer among older adults are expected to continue to increase over the next 11 years.

CONCLUSION

The global burden of pancreatic cancer among older adults has continued to rise over the past 30 years, and cross-national health inequalities remain high. Therefore, targeted measures must be taken to address this inequality.

The burden of pancreatic cancer and its attributable risk factors in the Middle East and North Africa region, 1990-2019

BACKGROUND AND AIM

Globally, pancreatic cancer is recognized as one of the most lethal types of cancers. We report the burden of pancreatic cancer and its attributable risk factors in the Middle East and North Africa (MENA) region, from 1990 to 2019, by age, sex, and socio-demographic index.

METHODS

Publicly available data from the Global Burden of Disease 2019 study were used to report the incidence, deaths, and disability-adjusted life years (DALYs) attributable to pancreatic cancer, as counts and age-standardized rates with 95% uncertainty intervals.

RESULTS

In 2019, pancreatic cancer had an age-standardized incidence rate of 5.3 and a death rate of 5.5 (per 100 000) in MENA, which have increased by 97.5% and 93.4%, respectively, since 1990. There were 563.6 thousand DALYs attributable to pancreatic cancer in 2019, with an age-standardized DALY rate of 123.0, which has increased by 84.9% since 1990. The highest number of incident cases was found in the 60-64 and 65-69 age groups, among male and female, respectively. In addition, the MENA/global DALY ratios were higher in all age groups for both sexes in 2019, than they were in 1990. There was a positive association between socio-demographic index and the burden of pancreatic cancer. Smoking, high fasting plasma glucose, and high body mass index were responsible for 19.2%, 9.3%, and 9.3% of the attributable DALYs in 2019, respectively.

CONCLUSIONS

There was a clear and substantial increase in the burden of pancreatic cancer in the MENA region. Prevention programs should be implemented in the region that target these three risk factors.

Increased Levels of miR-15b-5p and miR-20b-5p in Pancreatic Ductal Adenocarcinoma with Hepatic Metastases

Pancreatic ductal adenocarcinoma (PDAC) is one of the most aggressive and lethal forms of cancer. The symptoms appear in advanced stages, and diagnostic and prognostic tests for the early detection of PDAC and disease evolution are not available. The dysregulation of microRNAs (miRNAs) has been associated with cancer development and progression, and some miRNAs have been reported to promote specific metastasis. In this study we aimed to identify the miRNAs dysregulated in PDAC tumoral tissues and a subset of miRNAs associated with tumoral characteristics, mainly metastasis presence and site. For this, the expression of 84 miRNAs was evaluated by qPCR in 30 tumoral tissues and 16 samples of non-tumoral pancreatic tissues. The comparison revealed 32 dysregulated miRNAs (19 upregulated and 13 downregulated) in the PDAC group. Reactome pathway over-representation analysis revealed that these miRNAs are involved in several biological pathways, including "ESR-mediated signaling", "PIP3 activates AKT signaling", and "Regulation of PTEN", among others. Moreover, our study identified an upregulation of miR-15b-5p and miR-20b-5p in the tumoral tissues of patients with hepatic metastasis, outlining these miRNAs as potential markers for hepatic metastasis. No significant difference in miRNA expression was observed in relation to anatomic location, lymphovascular invasion, lung metastasis, and the presence of diabetes.

Body mass index and pancreatic adenocarcinoma: A nationwide registry-based cohort study

BACKGROUND AND OBJECTIVE

An association between body mass index (BMI) and pancreatic cancer is suggested in observational studies. However, further studies are required to substantiate available evidence. The aim of this study was to explore the association between BMI and pancreatic ductal adenocarcinoma (PDAC) risk, treatment, and mortality.

METHODS

A registry-based cohort study was performed by combining data from four registries in Norway. Baseline data were collected between 1963 and 1975 with follow-up data collected until 2018. Kaplan-Meier curves and multivariable Cox regressions were estimated. Chi-square tests were used to analyze differences between groups.

RESULTS

The study cohort consisted of 1,723,692 individuals. A total of 8973 PDAC cases were identified during 55,744,749 person-years of follow-up. A 5 kg/m² increase in BMI was associated with an increased risk of PDAC if high BMI at young age (16-29 years) (hazard ratio (HR): 1.21, 95% confidence interval (CI): 1.13-1.31), both for men (HR: 1.30, 95% CI: 1.15-1.46) and women (HR: 1.16, 95% CI: 1.05-1.28). In men, there was a 52% increase in risk of early-onset PDAC (<age 50) (HR: 1.52, 95% CI: 1.13-2.03) with 5 kg/m² increase in BMI. A total of 2645 individuals were diagnosed with stage 1-3 disease, of whom 1131 underwent curative surgery. In all, 49% of normal weight, 38% overweight, and 30% obese individuals with stage 1-3 PDAC underwent surgery with curative intent (p < 0.001). Cancer survival was lower in overweight and obese individuals for both sexes. Analysis adjusted for sex, age, and period of diagnosis confirmed increased risk of cancer death in obese individuals.

CONCLUSION

This study suggests that increased BMI in young adults may increase the risk of PDAC, and higher BMI in men is associated with an increased risk of early onset PDAC (<age 50). Overweight and obese individuals were less likely to undergo curative surgery and obese individuals had a higher risk of cancer-related death.

Characterization of Estrogen Receptors in Pancreatic Adenocarcinoma with Tertiary Lymphoid Structures

The role of estrogen signaling in antitumor immunology remains unknown for non-traditional sex-biased cancer types such as pancreatic adenocarcinoma (PAAD). Tertiary lymphoid structures (TLS) are active zones composed of multiple types of immune cells, whose presence indicates anti-tumor immune responses. In this study, we employed a 12-chemokine signature to characterize potential gene categories associated with TLS development and identified seventeen major gene categories including estrogen receptors (ERs). Immunohistochemistry staining revealed the expression patterns of three ERs (ERα, ERβ, and GPER) in 174 PAAD samples, and their correlation with clinicopathological characteristics, immune cell infiltration levels, and intratumoral TLS presence was analyzed. The results indicated that ERα (+) and ERβ (+) were correlated with high tumor grade, and ERβ (+) and GPER (+) were correlated with lower TNM stage, and both ERα (+) and GPER (+) displayed a beneficial effect on prognosis in this cohort. Interestingly, positive staining of all three ERs was significantly correlated with the presence of intratumoral TLSs and infiltration of more active immune cells into the microenvironment. Moreover, the chemotaxis of CD8⁺T-cells to PAAD cells was significantly increased in vitro with upregulated expression of ERα or ERβ on PAAD cells. To conclude, our study showed a novel correlation between ER expression and TLS development, suggesting that ERs may play a protective role by enhancing anti-tumor immune responses in PAAD.

Adherence to Mediterranean Diet and Risk of Pancreatic Cancer: Systematic Review and Meta-Analysis

Pancreatic cancer (PC) represents the 6th cause of cancer death. Although the aetiology of PC is not completely understood, numerous risk factors have been identified in association with this cancer, among them diet. However, little is known about the association between the Mediterranean Diet (MedDiet) and the risk of PC. For this reason, we conducted a systematic review with meta-analysis according to the PRISMA guidelines, searching on three databases (PubMed/MEDLINE, Scopus, and EMBASE). The protocol was registered in PROSPERO. Both fixed and random effect models were performed. The Effect size was reported as a hazard ratio (HR) with a 95% Confidence Interval (CI). A total of eight articles were included. The methodological quality of the included meta-analyses was high. Our results show that a higher adherence to the MedDiet is associated with a lower risk of PC [HR:0.82 (0.76-0.88) p < 0.001, based on 1,301,320 subjects]. The results were also confirmed in sensitivity and subgroups analyses (avoidance of potential overlapping effects, type of tools used to assess dietary intake and the diagnosis of PC, prevalence and incidence of PC risk, country where the studies took place, sex, and cancer site). Promoting a higher adherence to the MedDiet could be an effective approach to reduce the risk of PC.

Association of Menopausal Hormone Therapy with Risk of Pancreatic Cancer: A Systematic Review and Meta-analysis of Cohort Studies

BACKGROUND

Although menopausal hormone therapy (MHT) is commonly prescribed, little is known about the association between MHT use and risk of pancreatic cancer.

METHODS

We searched PubMed, Embase, and Cochrane Library, from inception until April 20, 2022. The risk of bias was assessed with the Newcastle-Ottawa Quality Assessment Scale. Pooled relative risks (RR) for pancreatic cancer risk were calculated using random-effects models. We computed prediction intervals (PI) and performed subgroup meta-analyses. Meta-regression was performed to investigate the sources of heterogeneity.

RESULTS

This study included 2,712,313 women from 11 cohort studies. There was no association between MHT and pancreatic cancer risk (RR, 0.92; 95% confidence interval (CI), 0.83-1.02; I2, 64%; 95% PI, 0.68-1.25). Subgroup meta-analyses of four studies stratified by MHT formulations showed inverse associations with the risk of pancreatic cancer (women receiving estrogen-only MHT: RR, 0.77; 95% CI, 0.64-0.94; I2, 57%; estrogen plus progestin MHT: RR, 0.85; 95% CI, 0.75-0.96; I2, 0%). Subgroup analysis defined by recency and duration of treatment did not reveal evidence of associations between MHT and pancreatic cancer risk.

CONCLUSIONS

This study found no association between the overall use of MHT and risk of pancreatic cancer. However, among four studies with data on MHT formulations, subgroup analysis showed a decreased risk of pancreatic cancer among users of estrogen-only and combined estrogen-progestin therapy. Owing to the inconsistent findings between our main and subgroup analyses, future studies stratified by MHT formulations are warranted.

IMPACT

The findings of this study indicate that future investigation should focus on MHT formulations.

Common variability in oestrogen-related genes and pancreatic ductal adenocarcinoma risk in women

The incidence of pancreatic ductal adenocarcinoma (PDAC) is different among males and females. This disparity cannot be fully explained by the difference in terms of exposure to known risk factors; therefore, the lower incidence in women could be attributed to sex-specific hormones. A two-phase association study was conducted in 12,387 female subjects (5436 PDAC cases and 6951 controls) to assess the effect on risk of developing PDAC of single nucleotide polymorphisms (SNPs) in 208 genes involved in oestrogen and pregnenolone biosynthesis and oestrogen-mediated signalling. In the discovery phase 14 polymorphisms showed a statistically significant association (P < 0.05). In the replication none of the findings were validated. In addition, a gene-based analysis was performed on the 208 selected genes. Four genes (NR5A2, MED1, NCOA2 and RUNX1) were associated with PDAC risk, but only NR5A2 showed an association (P = 4.08 × 10-5) below the Bonferroni-corrected threshold of statistical significance. In conclusion, despite differences in incidence between males and females, our study did not identify an effect of common polymorphisms in the oestrogen and pregnenolone pathways in relation to PDAC susceptibility. However, we validated the previously reported association between NR5A2 gene variants and PDAC risk.

Burden of pancreatic cancer along with attributable risk factors in China from 1990 to 2019, and projections until 2030

OBJECTIVES

Understanding epidemiology trends and patterns of pancreatic cancer in China from 1990 to 2019 and predicting the burden to 2030 will provide foundations for future policies development.

METHODS

We collected incidence, mortality, and disability-adjusted life-years (DALYs) data of pancreatic cancer in China from 1990 to 2019 based on the Global Burden of Disease Study 2019. We calculated the estimated annual percentage change (EAPC) to depict the trends of pancreatic cancer burden and predicted the incidence and mortality in the next decade by using a Bayesian age-period-cohort analysis.

RESULTS

The number of incident cases sharply increased from 26.77 thousand in 1990 to 114.96 thousand in 2019, the age-standardized incidence rate (ASIR) nearly doubled from 3.17 per 100,000 in 1990 to 5.78 per 100,000 in 2019, with an EAPC of 2.32 (95% confidence interval [CI]: 2.12, 2.51). The mortality and DALYs presented a similar pattern with incidence. The dominant risk factor for pancreatic cancer was smoking, but the contribution of high body-mass index increased from 1990 to 2019. We projected that the incident cases and deaths of pancreatic cancer would increase to 218.79 thousand and 222.97 thousand, respectively, in 2030 with around 2 times growth.

CONCLUSIONS

During the past three decades, the incidence, mortality and DALYs of pancreatic cancer gradually increased in China, and the absolute number and rate of pancreatic cancer burden would continue to rise over the next decade. Comprehensive policies and strategies need to be implemented to reduce the incidence and mortality.

Sex, Gender and Age Differences in Treatment Allocation and Survival of Patients With Metastatic Pancreatic Cancer: A Nationwide Study

Background

Biological sex, gender and age have an impact on the incidence and outcome in patients with metastatic pancreatic cancer. The aim of this study is to investigate whether biological sex, gender and age are associated with treatment allocation and overall survival (OS) of patients with metastatic pancreatic cancer in a nationwide cohort.

Methods

Patients with synchronous metastatic pancreatic cancer diagnosed between 2015 and 2019 were selected from the Netherlands Cancer Registry (NCR). The association between biological sex and the probability of receiving systemic treatment were examined with multivariable logistic regression analyses. Kaplan Meier analyses with log-rank test were used to describe OS.

Results

A total of 7470 patients with metastatic pancreatic cancer were included in this study. Fourty-eight percent of patients were women. Women received less often systemic treatment (26% vs. 28%, P=0.03), as compared to men. Multivariable logistic regression analyses with adjustment for confounders showed that women ≤55 years of age, received more often systemic treatment (OR 1.82, 95% CI 1.24-2.68) compared to men of the same age group. In contrast, women at >55 years of age had a comparable probability to receive systemic treatment compared to men of the same age groups. After adjustment for confounders, women had longer OS compared to men (HR 0.89, 95% CI 0.84-0.93).

Conclusion

This study found that women in general had a lower probability of receiving systemic treatment compared to men, but this can mainly be explained by age differences. Women had better OS compared to men after adjustment for confounders.

Disparities of birth cohort effects on pancreatic cancer incidence between the United States and urban China

Background

Pancreatic cancer has been associated with lifestyle factors, but few comparative studies were conducted among countries of different culture and lifestyle habits. This study compared the trends of pancreatic cancer incidence and birth cohort effects in the United States and urban China and explored the potential discrepancies of risk patterns.

Materials and methods

Age-standardized incidence rates (ASIRs) were calculated using data from national or regional cancer registries of the United States and two large cities of China (Shanghai, Hong Kong). The temporal trends of incidence were assessed by joinpoint regression. The effects of birth cohort and calendar period were identified through age–period–cohort modeling.

Results

The ASIR in the United States from 1976 to 2015 was 8.26/100 000, which was higher than that in Hong Kong (4.29/100 000) and Shanghai of China (6.63/100 000). Shanghai had lower incidence (4.41/100 000) in 1976-1980 but increased annually by 1.38% in males and 1.67% in females, with a sharper upward trend than the United States and Hong Kong. Males had higher risks than females, with a male-to-female ratio of 1.34, 1.44, and 1.37 in the United States, Hong Kong, and Shanghai, respectively. A significant and prominent increase in incidence rate was observed among successive generations in China particularly for Shanghai, but such a pattern was not apparent in the United States.

Conclusions

The differences in pancreatic cancer incidence by sex may be multi-factorial involving known risk factors like tobacco smoking and alcohol consumption. The significant birth cohort effects among recent and early generations in the Shanghai population were in line with a society in socioeconomic transition and adoption of Western lifestyle mainly including consumption of calorie-rich foods and physical inactivity. Differences in these risk patterns will have implications on health care efforts and policies for cancer control.

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The ASIR of pancreatic cancer in the U.S. is higher than that in urban China.

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Higher risk of pancreatic cancer was observed in the youth of urban China, but this pattern was not prominent in the U.S.

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The disparities of birth cohort effects are consistent with a society in socioeconomic transition.

Association between oral contraceptive use and pancreatic cancer risk: A systematic review and meta-analysis

BACKGROUND

Studies on the association of oral contraceptive (OC) use and pancreatic cancer showed inconsistent findings.

AIM

To evaluate the relationship between OC use and pancreatic cancer risk.

METHODS

A literature search for observational studies (case-control and cohort studies) was conducted up to December 2020. A meta-analysis was performed by calculating pooled relative risks (RRs) and 95% confidence intervals (CIs). Heterogeneity was assessed using Cochran’s chi-square test and I² statistic. Subgroup analyses were performed by study design, source of controls in case-control studies, number of cases of pancreatic cancers, study quality according to Newcastle-Ottawa Scale score, geographical region and menopausal status. All analyses were performed using Review Manager 5.3 (RevMan 5.3).

RESULTS

A total of 21 studies (10 case-control studies and 11 cohort studies) were finally included in the present meta-analysis, comprising 7700 cases of pancreatic cancer in total. A significant association was observed between the ever use of OC and pancreatic cancer risk in the overall analysis (RR = 0.85; 95%CI = 0.73-0.98; P = 0.03). Duration of OC use (< 1 year, < 5 years, 5-10 years, > 10 years) was not significantly associated with the risk of pancreatic cancer. Subgroup analyses revealed a statistically significant subgroup difference for the geographic region in which the study was conducted (Europe vs Americas vs Asia; P = 0.07). Subgroup analyses showed a statistically significant decrease in pancreatic cancer risk and OC use in high-quality studies, studies conducted in Europe, and in postmenopausal women.

CONCLUSION

Despite the suggested protective effects of OC use in this meta-analysis, further epidemiological studies are warranted to fully elucidate the association between the use of OC and pancreatic cancer risk.

Role of G Protein-Coupled Estrogen Receptor in Digestive System Carcinomas: A Minireview

Digestive system carcinomas are one of the leading causes of cancer-related deaths worldwide. G protein-coupled estrogen receptor (GPER), a novel estrogen receptor, has been recognized as an important mediator in numerous cancer types. Recently, the function and clinical significance of GPER in digestive system carcinomas has been a subject of interest. Increasing evidence has revealed that GPER plays an important role as a potential biomarker in digestive system carcinomas. This work summarizes the recent literature and focuses on the emerging functional role of GPER in digestive system carcinomas, including gastric cancer, hepatocellular carcinoma, pancreatic cancer, and colorectal cancer. The potential application of GPER in novel strategies for the diagnosis and treatment of digestive system carcinomas is discussed and highlighted.

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.

Reproductive Factors, Use of Exogenous Hormones, and Pancreatic Cancer Incidence: The Norwegian Women and Cancer Study

Introduction

The incidence of pancreatic cancer is increasing worldwide and characterized by a particularly low survival rate. Studies have reported weak and inconsistent evidence for associations among reproductive factors, use of exogenous hormones, and pancreatic cancer incidence in women.

Purpose

To investigate relationships between reproductive factors, exogenous hormones, and the rate of pancreatic cancer incidence in a large population-based prospective cohort of women in Norway.

Methods

We used data from the Norwegian Women and Cancer study on 588 incident cases of pancreatic cancer diagnosed among 165,419 women, with mean follow-up of 18.7 years. Cox proportional-hazard models were used to estimate HRs and 95% CIs for associations of interest.

Results

Cumulative breastfeeding duration >24 months was associated with 63% decreased incidence of pancreatic cancer compared to no breastfeeding. We observed an inverse linear dose–response trend between cumulative breastfeeding duration and pancreatic cancer incidence, which was confirmed in parous women and ever-smokers. Higher age at first birth and menopause were inversely associated with pancreatic cancer incidence, though with less precise effect estimates. Current use of oral contraceptives was associated with a doubling of pancreatic cancer incidence, but the analysis was hampered by a small number of cases. There was no evidence of any associations between age at menarche, parity or use of menopausal hormone therapy, and incidence of pancreatic cancer.

Conclusion

Our results suggest a potential protective effect of breastfeeding duration against pancreatic cancer incidence. Inconsistent results for the other reproductive factors suggested no important role of estrogens in pancreatic cancer etiology.

Raloxifene inhibits pancreatic adenocarcinoma growth by interfering with ERβ and IL-6/gp130/STAT3 signaling

PURPOSE

Currently, the exact role of estrogen receptor (ER) signaling in pancreatic cancer is unknown. Recently, we showed that expression of phosphorylated ERβ correlates with a poor prognosis in patients with pancreatic ductal adenocarcinoma (PDAC). Here, we hypothesized that raloxifene, a FDA-approved selective ER modulator (SERM), may suppress PDAC tumor growth by interfering with ERβ signaling. To test this hypothesis, we studied the impact of raloxifene on interleukin-6/glycoprotein-130/signal transducer and activator of transcription-3 (IL-6/gp130/STAT3) signaling.

METHODS

Human PDAC cell lines were exposed to raloxifene after which growth inhibition was assessed using a BrdU assay. ER knockdown was performed using siRNAs specific for ERα and ERβ. The effects of raloxifene on IL-6 expression and STAT3 phosphorylation in PDAC cells were assessed by ELISA and Western blotting, respectively. In addition, raloxifene was administered to an orthotopic PDAC tumor xenograft mouse model, after which tumor growth was monitored and immunohistochemistry was performed.

RESULTS

Raloxifene inhibited the in vitro growth of PDAC cells, and this effect was reversed by siRNA-mediated knockdown of ERβ, but not of ERα, indicating ER isotype-specific signaling. We also found that treatment with raloxifene inhibited the release of IL-6 and suppressed the phosphorylation of STAT3Y705 in PDAC cells. In vivo, we found that orthotopic PDAC tumor growth, lymph node and liver metastases as well as Ki-67 expression were reduced in mice treated with raloxifene.

CONCLUSIONS

Inhibition of ERβ and the IL-6/gp130/STAT3 signaling pathway by raloxifene leads to potent reduction of PDAC growth in vitro and in vivo. Our results suggest that ERβ signaling and IL-6/gp130 interaction may serve as promising drug targets for pancreatic cancer and that raloxifene may serve as an attractive therapeutic option for PDAC patients expressing the ERβ isotype.

Poultry and Fish Intake and Pancreatic Cancer Risk: A Systematic Review and Meta-Analysis

Although several epidemiological studies have investigated associations between poultry and fish consumption and pancreatic cancer (PC) risk, these findings have been inconsistent. The present study aimed to perform a meta-analysis to comprehensively evaluate these associations. We retrieved Eligible cohort studies and case-control studies published before February 2020 from the Medline, EMBASE, and Cochrane Library and applied a random or fixed effects model to calculate the pooled relative risk (RR) and the corresponding 95% confidence intervals (CI). Publication bias was detected using funnel plots, Begg's test, and Egger's test, and the study quality was evaluated using the Newcastle-Ottawa scale. We included 25 studies in the analyses. The pooled RR of PC for the highest vs. lowest poultry intake category was 1.14 (95% CI: 1.02-1.26) in cohort studies. There was no appreciable link between fish intake and PC risk (RR: 1.00, 95% CI: 0.93-1.07). Our results suggest that large amount of poultry intake may increase PC risk, while fish intake is unlikely to be linked to PC risk. These links require further investigation, particularly between poultry and PC.

The Sex Bias of Cancer

In hormone-dependent organs, sex hormones and dysregulated hormone signaling have well-documented roles in cancers of the breast and female reproductive organs including endometrium and ovary, as well as in prostate and testicular cancers in males. Strikingly, epidemiological data highlight significant differences between the sexes in the incidence of various cancers in nonreproductive organs, where the role of sex hormones has been less well studied. In an era when personalized medicine is gaining recognition, understanding the molecular, cellular, and biological differences between men and women is timely for developing more appropriate therapeutic interventions according to gender. We review evidence that sex hormones also shape many of the dysregulated cellular and molecular pathways that lead to cell proliferation and cancer in nonreproductive organs.

Gynecological and reproductive factors and the risk of pancreatic cancer: A case-control study

BACKGROUND

/Objectives: Pancreatic ductal adenocarcinoma (PDAC) has a higher incidence in men compared to women, although the difference in known risk factors cannot explain this disparity completely. Reproductive and hormonal factors have been demonstrated in pre-clinical studies to influence pancreatic carcinogenesis, but the few published data on the topic are inconsistent. The aim was to investigate the role of reproductive and hormonal factors on PDAC occurrence in women.

METHODS

We conducted a unicenter case-control study; PDAC cases were matched to controls by age with a 1:2 ratio. Risk factors were screened through questionnaires about gynecologic and medical history. Comparisons were made using Chi-square and Fisher's exact tests where appropriate for categorical variables and Student's t-test for continuous variables. Logistic regression was used to calculate Odds Ratios (ORs) and their 95% confidence intervals (CI). Multivariable logistic regression models were adjusted for potential confounders.

RESULTS

253 PDAC and 506 matched controls were enrolled. At logistic regression multivariable analysis adjusted for confounding factors, older age at menopause (OR:0.95 per year; 95% CI:0.91-0.98; p = 0.007), use of Oral Contraceptives (OR:0.52; 95% CI:0.30-0.89; p = 0.018), use of Hormonal Replacement Therapy (OR:0.31; 95% CI:0.15-0.64; p = 0.001), and having had two children (OR:0.57; 95% CI:0.38-0.84; p = 0.005) were significant, independent protective factors for the onset of PDAC.

CONCLUSIONS

These data confirm some previous findings on menopause age and number of births while, to our knowledge, this is the first study to show a protective effect of HRT and OC use. The results collectively support the hypothesis that exposure to estrogens plays a protective role towards PDAC.

Pharmacologic Activation of the G Protein-Coupled Estrogen Receptor Inhibits Pancreatic Ductal Adenocarcinoma

BACKGROUND & AIMS

Female sex is associated with lower incidence and improved clinical outcomes for most cancer types including pancreatic ductal adenocarcinoma (PDAC). The mechanistic basis for this sex difference is unknown. We hypothesized that estrogen signaling may be responsible, despite the fact that PDAC lacks classic nuclear estrogen receptors.

METHODS

Here we used murine syngeneic tumor models and human xenografts to determine that signaling through the nonclassic estrogen receptor G protein-coupled estrogen receptor (GPER) on tumor cells inhibits PDAC.

RESULTS

Activation of GPER with the specific, small molecule, synthetic agonist G-1 inhibited PDAC proliferation, depleted c-Myc and programmed death ligand 1 (PD-L1), and increased tumor cell immunogenicity. Systemically administered G-1 was well-tolerated in PDAC bearing mice, induced tumor regression, significantly prolonged survival, and markedly increased the efficacy of PD-1 targeted immune therapy. We detected GPER protein in a majority of spontaneous human PDAC tumors, independent of tumor stage.

CONCLUSIONS

These data, coupled with the wide tissue distribution of GPER and our previous work showing that G-1 inhibits melanoma, suggest that GPER agonists may be useful against a range of cancers that are not classically considered sex hormone responsive and that arise in tissues outside of the reproductive system.

Clinical significance of stromal ER and PR expression in periampullary adenocarcinoma

BACKGROUND

Tamoxifen treatment has previously been reported to confer life-prolonging effects in patients with advanced pancreatic cancer, and most evidently so in women. None of these trials did however include biomarkers, and the relevance of female hormone signaling in pancreatic or other periampullary adenocarcinoma remains largely unexplored. The aim of this study was to examine the extent and potential clinical significance of estrogen receptor-α (ER) and progesterone receptor (PR) expression in pancreatic and other periampullary cancers.

METHODS

ER and PR expression was examined using immunohistochemistry on tissue microarrays with primary tumors from a retrospective consecutive cohort of 175 patients with resected periampullary adenocarcinoma, with long-term clinical follow-up. Non-parametric and Chi square tests were applied to examine the associations of stromal ER and PR expression with patient and tumor characteristics. Kaplan-Meier analysis and log rank test were applied to illustrate survival differences in relation to ER and PR expression. Cox regression proportional hazards models were applied to examine the associations between investigative factors and risk of death and recurrence, and to test for interactions between KRAS mutation status and hormone receptor expression in relation to survival.

RESULTS

Expression of both ER and PR was more frequent in the tumor-associated stroma than in the epithelium. A significant prognostic interaction, independent of tumor morphology, was found between stromal PR expression and KRAS mutation status in relation to both overall and recurrence-free survival (pinteraction = 0.026 and pinteraction = 0.005), in particular in women (pinteraction = 0.002 and pinteraction = 0.005). Specifically, stromal PR expression was associated with a prolonged survival in patients with KRAS-mutated tumors, whereas the opposite was seen for KRAS wild-type tumors. The prognostic value of ER positivity was limited to the subgroup of women with tumors of pancreatic origin.

CONCLUSIONS

These results demonstrate that stromal PR rather than ER expression, together with KRAS mutation status, provides long-term prognostic information in patients with periampullary adenocarcinoma. Further study into the mechanistic basis for these observations may unveil important clues to the pathogenesis of these cancers and open up for the discovery of novel treatment options.

Smoking and Pancreatic Cancer Incidence: A Pooled Analysis of 10 Population-Based Cohort Studies in Japan

BACKGROUND

Detailed prospective evaluation of cigarette smoking associated with pancreatic cancer risk in large Asian populations is limited. The aim of this study was to examine this association in a Japanese population, with a particular focus on evaluating sex differences.

METHODS

We performed a pooled analysis of 10 population-based cohort studies. We calculated study-specific HRs and 95% confidence intervals (CI) using Cox proportional hazards regression, and then estimated summary HRs by pooling these estimates with a random effects model.

RESULTS

During 4,695,593 person-years of follow-up in 354,154 participants, 1,779 incident pancreatic cancer cases were identified. We observed an increased pancreatic cancer risk for current smoking compared with never smoking in both males [HR (95% CI), 1.59 (1.32-1.91)] and females [HR (95% CI), 1.81 (1.43-2.30)]. Significant risk elevations for former smoking and small cumulative dose of ≤20 pack-years (PY) were observed only among females, regardless of environmental tobacco smoke exposure. Trend analysis indicated significant 6% and nonsignificant 6% increases in pancreatic cancer risk for every 10 PYs in males and females, respectively. Risk became comparable with never smokers after 5 years of smoking cessation in males. In females, however, we observed no risk attenuation by smoking cessation.

CONCLUSIONS

This study supports the well-known association between smoking and pancreatic cancer and indicates potential sex differences in a Japanese population. Quitting smoking would be beneficial for pancreatic cancer prevention, especially in males.

IMPACT

Pancreatic cancer risk is increased with cumulative smoking exposure and decreased with smoking cessation, with potential sex differences.