Introduction

Pancreatic ductal adenocarcinoma (PDAC) is in the tenth place of newly diagnosed case of all tumors and one of the most lethal cancer related malignancies in developed countries [1]. Surgical reduction still is the main treatment method, but often not effective due to the advanced stage. Immunotherapy is a promising treatment for many cancers. However, the efforts and attempts to use immunotherapy in the treatment of PDAC are extensive and real breakthroughs have not been achieved [2]. Peripheral blood mononuclear cells (PBMC) as immune cells are crucial for the body's response against cancer [3]. One of the main immune checkpoint member is programmed cell death protein 1 (PD1). It is known that PD1 expression in T cells is strongly regulated by aryl hydrocarbon receptor (AHR) [4]. Moreover, there are immunological barriers to treatment challenge in cancer like insufficient immune function activation and excess immune suppression [5]. Previously we analyzed immune response disbalance regards of AHR expression in PDAC patients PBMCs. Results showed significant changes of lower AHR gene expression patients' group. Next, we decided to check PBMCs functions in healthy participants after indirect interaction with pancreatic cancer cells. We hypothesized that AHR expression differences in PBMCs could regulate anti-cancer response.

Aims & Methods

The aim of this study was to analyze PBMCs functions and targets expression of healthy participants after indirect interaction with pancreatic cancer cells. PBMCs (n=11) were isolated from peripheral blood by Ficoll-Paque gradient centrifugation. Analysis was done at 3 points. The first point of study was prepared immediately after PBMCs isolation. Second and third points were prepared after 20h of PBMCs -/+ co-cultivation with BxPC3 cells. Phagocytic activity analysis was prepared after 3-hour PBMCs activation with LPS. ROS production was measured effecting with TBHP. NO production was measured after activation with LPS + L-Arginine. Simultaneously PBMCs metabolic activity was measured by resazurin assay. Monocytes and lymphocytes differentiation was evaluated by FACS analysis. Gene expressions were analyzed by RT-PCR method. Statistical analysis was performed using GraphPad software and the Mann – Whitney test.

Results

The results showed that AHR and IL1b, IL6, IL10 mRNA were increased, only IL6 was significantly upregulated after PBMC co-cultivation with BxPC3 cells. While PD1 and IL4 mRNA expression were decreased. The expression of AHR strongly negatively correlated with expression of PD1 in healthy volunteers PBMCs’ after co-cultivation with cancer cells. M1 type monocytes and NK cells decreased after co-cultivation with PDAC cells. Moreover, M0 type monocytes and cytotoxic T lymphocytes were increased. Phagocytic activity and NO production were more intensive in PBMC cells after co-cultivation. ROS production did not show significant changes.

Conclusion

This study showed negative PD1 gene expression correlation with AHR expression after indirect interactions with cancer cells in healthy participants PBMCs. Also, PBMCs co-cultivation with cancer cells initiated strong functional response and higher expression of inflammatory cytokines. These results show us different AHR relations with immunity response in healthy and cancer patients. Meanwhile, this knowledge lets us understand the importance of AHR modulation as an additional PDAC treatment strategy.

References

1. Siegel, R. L., Miller, K. D., Wagle, N. S., & Jemal, A. (2023). Cancer statistics, 2023. CA: A Cancer Journal for Clinicians, 73(1), 17-48. doi:10.3322/caac.21763
2. Mundry, C. S., Eberle, K. C., Singh, P. K., Hollingsworth, M. A., & Mehla, K. (2020). Local and systemic immunosuppression in pancreatic cancer: Targeting the stalwarts in tumor’s arsenal. Biochimica Et Biophysica Acta. Reviews on Cancer, 1874(1), 188387. doi:10.1016/j.bbcan.2020.188387
3. Griffin JF, Poruk KE, Wolfgang CL. Pancreatic cancer surgery: past, present, and future. Chin J Cancer Res. 2015 Aug;27(4):332-48
4. Liu, Y., Liang, X., Dong, W., Fang, Y., Lv, J., Zhang, T., . . . Huang, B. (2018). Tumor-repopulating cells induce PD1 expression in CD8+ T cells by transferring kynurenine and AhR activation. Cancer Cell, 33(3), 480-494.e7. doi: 10.1016/j.ccell.2018.02.005
5. Rojas, L. A., & Balachandran, V. P. (2021). Scaling the immune incline in PDAC. Nature Reviews. Gastroenterology & Hepatology, 18(7), 453-454. doi:10.1038/s41575-021-00475-9

Disclosure

The authors have no conflicts of interest to declare

Introduction

Despite decades of extensive research, pancreatic ductal adenocarcinoma (PDAC) has been predicted to rise to the second leading cause of cancer-related death in 2030. A major hallmark of pancreatic cancer is a strong desmoplastic reaction and reduced vascularization, resulting in reduced nutrient perfusion. Although previous studies have demonstrated how the mutational landscape impacts the metabolic phenotype, assigning specific metabolic patterns to a given genotype is still of high interest for development of targeted therapeutic approaches. Homologous recombination deficiency (HRD), caused by mutations such as ATM, promotes PDAC aggressiveness, a mesenchymal phenotype, and a desmoplastic reaction.

Aims & Methods

To assess the impact of ATM deficiency driven HRD on PDAC metabolism, we investigated murine ATM-knockout PDAC cell lines. Precisely, we performed a wide range of in vitro experiments to determine cell viability, apoptosis, and functionality, of PDAC cells, as well as ATP production rates under normal and nutrient-depleted conditions. To decipher the underlying mechanisms of metabolic reprogramming in Atm-deficient PDAC cells, an individualized compound library targeting the main metabolic pathways for energy and macromolecule production was designed.

Results

Here, we show that loss of ATM facilitates the adaptation of PDAC cells to nutrient scarcity, evading metabolic stress-induced apoptosis. Mechanistically, adaptation to nutrient stress was accompanied by a higher vulnerability to inhibitors targeting ATP generating pathways oxidative phosphorylation (OxPhos) and glycolysis, as well as pentose phosphate pathway branching from glycolysis. Furthermore, especially in a metabolic stress context, Atm-deficient cells seem to rely on acetate metabolism, which is channeled into fatty acid synthesis and TCA cycle/ OxPhos. In line, loss of ATM correlated with increased ATP production. These in vitro results are supported by protein expression data in human PDAC showing a negative correlation between expression of ATM and enzymes related with OxPhos, glycolysis and acetate metabolism. Additionally, loss of ATM promotes maintenance of PDAC cell aggressive features under nutrient starvation, including a mesenchymal phenotype and DNA damage accumulation.

Conclusion

Our results indicate that specific metabolic reprogramming, affecting ATP generation and macromolecule biosynthesis pathways and occurring in ATM-deficient malignant HRD cells upon nutrient stress, promotes cell survival and tumor aggressiveness, which may ultimately contribute to cancer progression. Overall, we demonstrate how PDAC cell biology is impacted by genotype-specific metabolic remodeling, enabling exploitation of HRDness metabolic vulnerabilities through various interference strategies.

Introduction

Proton pump inhibitors (PPIs) are extensively prescribed due to the widespread diagnosis of gastro-oesophageal disease (GORD). ^1,2 Overutilisation of PPIs is common, and growing concerns over adverse events, inappropriate prescribing and unnecessary costs ^3,4 are driving exploration into the implementation of holistic management, including deprescription strategies¹.

Aims & Methods

We aimed to quantify healthcare professionals’ (HCPs) preferences on the management of GORD in the UK, and identify attributes perceived as enhancing or detracting from quality of care.
Attributes were derived from qualitative data gathered through 3 focus groups with gastroenterologists, pharmacists and general practitioners (GPs), and interviews with 4 GORD patients.
A discrete-choice experiment (DCE) was developed and administered via online survey (Jan–Apr 2025) to 38 HCPs. Respondents chose between paired hypothetical GORD management scenarios, varying by symptom severity, appointment frequency, treatment approach, information delivery method, and cost. Preferences were modelled using a multinomial conditional logit with effects coding. Marginal rates of substitution (MRS) were calculated to quantify trade-offs.

Results

74% of respondents were pharmacists (n=28) and 26% GPs (n=10). All had managed GORD patients in the past year, and 81% expressed concern over long-term PPI use.
A holistic approach combining PPIs with lifestyle modification was strongly preferred over PPI monotherapy (β=0.4244, p<0.001), representing the most influential driver of care quality. Lifestyle modification alone was also favoured over PPI monotherapy (β=0.1125), though this did not reach statistical significance (p=0.127).
Respondents expressed significant aversion to providing information via pamphlets compared to GP-led counselling (β=–0.1836, p=0.046), while no preference emerged between pharmacist- and GP-led counselling (β=0.0512, p=0.573). Neither appointment burden nor out-of-pocket costs significantly influenced decision-making.
Symptom severity was a notable driver: HCPs selected scenarios involving moderate symptoms over mild (β=0.2353, p=0.005), indicating increased urgency and prioritisation for moderate disease.
Analysis of MRS between attributes suggested that HCPs are willing to accept 4.4 additional appointments to manage moderate symptoms, rather than mild, and nearly 8 additional appointments to deliver combined holistic lifestyle and pharmacological therapy. This highlights a willingness to absorb appointment-related resource demands in favour of more comprehensive, effective care.

Conclusion

Concerns around long-term PPI use support a shift toward active GORD management and PPI deprescribing, with structured follow-up to monitor treatment response.
This interim analysis highlights a clear preference among HCPs for multimodal GORD management, particularly combining lifestyle modification with pharmacological treatment, and reinforces the importance of interactive clinician[BA1] -led patient education, which can promote compliance and improve outcomes. The willingness to accept 4.4 additional appointments reflects the value placed on ongoing monitoring and personalised care. However, this raises the question on the impact this may have on health services, and whether the integration of self-care into multimodal approaches developed with HCPs could be an alternative solution to be investigated. [LH2] These findings highlight the need for a system-wide shift toward guideline-informed, stepped-care models.
A further analysis on patient population preferences is under review.

References

1. Savarino E, Anastasiou F, Labenz J, Hungin APS, Mendive J. Holistic management of symptomatic reflux: rising to the challenge of proton pump inhibitor overuse. Br J Gen Pract. 2022; 72(724):541-544.
2. Hungin APS, Scarpignato C, Keefer L, Corsetti M, Anastasiou F, Muris JWM, Mendive JM, Kahrilas PJ. Review article: rethinking the "ladder" approach to reflux-like symptom management in the era of PPI "resistance" - a multidisciplinary perspective. Aliment Pharmacol Ther. 2022; 55(12):1492-1500.
3. Plehhova K, Wray J, Aluko P, Sutton S, McArdle J, Dawson A, Coyle C, Stevens RM. Prescribing practices for proton pump inhibitors among primary care physicians in England: an evaluation. BJGP Open. 2025.
4. Sosio J, McKee N, [BA1] [LH2] Gold R, Singson A, Boroda K. S579 PPI Stewardship: A Quality Improvement Tool to Improve Long-Term Prescribing Practices. Am J Gastroenterol. 2024; 119(10S): S400.

Disclosure

This study was funded by Reckitt Benckiser Healthcare Ltd.
K. Plehhova, and E. Horvath are employees of Reckitt.

Introduction

Despite advances in cancer treatment, pancreatic adenocarcinoma continues to have a poor prognosis and remains a leading cause of death among all tumors [1]. Most pancreatic adenocarcinoma patients are diagnosed in stages with metastasis. Moreover, pancreatic adenocarcinoma has a restricted ability to respond to immunotherapy due to low immune infiltration. Prior studies have demonstrated a correlation between tumor endothelial cells (TECs) and angiogenesis, which has been indicated to play a critical role in T-cell-mediated immunosurveillance [2]. Identifying the specific subpopulation of TEC that correlates with immune evasion in pancreatic adenocarcinoma remains a challenge. However, to clarify this subpopulation may bring novel hope to patients with pancreatic adenocarcinoma.

Aims & Methods

Our study aimed to identify the specific subpopulation of TECs associated with increased immunoevasion. Analysis based on the TCGA database, scRNA-seq, the online tool Kaplan Meier plotter, and spatial transcriptomics data were utilized in our study. Moreover, we cultured human umbilical vein endothelial cells (HUVECs) and performed siRNA transfection and Western blotting to confirm the function of RASIP1 in endothelial cells.

Results

Genes related to patient survival in pancreatic adenocarcinoma were identified by the analysis from the Cancer Genome Atlas (TCGA). On the other hand, based on scRNA-seq data, the genes exclusively expressed in endothelial cells were identified. Our analysis revealed that RASIP1 (Ras Interacting Protein 1) was specifically expressed in endothelial cells and linked to improved pancreatic cancer patient survival. Subsequently, the gene ontology analysis of RASIP1-positive TECs was performed based on the scRNA-seq data, and it turned out that RASIP1-positive TECs were related to leukocyte transendothelial migration. Intriguingly, based on the analysis of the TCGA database and spatial transcriptomics data, it was revealed that RASIP1-positive TECs are correlated with increased T cell infiltration and elevated T-effector and IFN-gamma gene signatures in pancreatic adenocarcinoma. These findings suggest that RASIP1-positive TECs may contribute to the "hot" tumor phenotype by promoting T cell infiltration. To further investigate the relationship between RASIP1 and leukocyte transendothelial migration, we knocked down RASIP1 in human umbilical vein endothelial cells (HUVECs) and found a decrease in the expression of the key adhesion molecule intercellular cell adhesion molecule (ICAM). Moreover, the potential related signaling pathway was also investigated, including Erk and p38. Intriguingly, the survival analysis based on patients with pan-cancer immunotherapy also indicated the expression of RASIP1 was proportional to the survival time of cancer patients receiving immunotherapy. In the patients with high expression of RASIP1, longer survival was shown, with a p-value of 0.014 and HR of 0.74. And particularly, in patients treated with PD-L1, significantly longer survival was shown in the group with high expression of RASIP1, with a p-value of 0.01 and HR of 0.74

Conclusion

All in all, our study revealed a potential novel type of endothelial cell in pancreatic adenocarcinoma, which correlated with increased leukocyte transendothelial migration and may provide a potentially effective therapeutic mechanism.

References

1. Ullman NA, Burchard PR, Dunne RF, Linehan DC. Immunologic Strategies in Pancreatic Cancer: Making Cold Tumors Hot. J Clin Oncol. 2022 Aug 20;40(24):2789-2805.
2. Nagl L, Horvath L, Pircher A, Wolf D. Tumor Endothelial Cells (TECs) as Potential Immune Directors of the Tumor Microenvironment - New Findings and Future Perspectives. Front Cell Dev Biol. 2020 Aug 19;8:766.

Introduction

Volatile organic compounds (VOC) in stool samples may reflect functional activity of gut microbiome. Previous studies showed that gut flora may influence transient relaxations of lower esophageal sphincter through short-chain fatty acids production and thus - participate in pathogenesis of gastroesophageal reflux disease (GERD). However, the role of VOC in pathogenesis of GERD is poorly studied yet.

Aims & Methods

The aim of this study (FGMF-2025-0003) was to perform correlation analysis between concentrations of VOC in stool samples and GERD-Q score.
We enrolled willing to participate patients referred to perform multichannel 24-h pH-impedance recording (Ohmega, Laborie). According to the Lyon 2.0 criteria patients were allocated to the GERD or the control group. GERD-Q questionnaire was filled in by the participants on the same day as stool samples were collected. Thermo TSQ 8000 triple quadrupole mass-spectrometer (GC/MS) was used for the measurement of VOCs in stool samples were analyzed with. Correlation analysis (Spearman rank R) was performed between values of 80 VOCs in stool samples and the results of GERD-Q questionnaire.

Results

Data of 76 patients were eligible: 42 with GERD and 34 - of the control group. Participants in the GERD group were older (54.7±12.2 y.o. vs 46±14.9 y.o., P<0.05) and their BMI was greater (30.9±5.2 vs 27.2±6.5 kg/m², P<0.05). GERD-Q score was logically greater in GERD group (11.0±2.5 vs 5.2±1.2, p<0.01). Correlation analysis revealed significant correlations between GERD-Q score and concentrations of 2-methylbutyric acid (Spearman R =-0.31), caproic acid (0.34) and enantiic acid (0.396) in stool samples.

Conclusion

GERD-Q score positively correlates with concentrations of Caproic acid (0.34) and Enantiic acid (0.396) in stool samples and negatively – with 2-Methylbutyric acid. The data of this pilot study may serve as a basis for further research on the role of functional activity of gut microbiome in pathogenesis of GERD.