Introduction

By 2030, pancreatic ductal adenocarcinoma (PDAC) is predicted to become the second leading cause of cancer-related death. Due to its resistance to conventional therapies and heterogeneous mutational landscape, molecular stratification and the development of targeted therapeutic options are essential for improving survival of PDAC patients. Previous work from our group investigated loss-of-function mouse models for the ATM serine/threonine kinase causing homologous recombination deficiency (HRD) in PDAC. Specifically, ATM loss was reported to accelerate tumorigenesis, support metastatic burden, and coincide with oncogenic programs, including epithelial-mesenchymal transition (EMT). Interestingly, ATM-deficient tumors accumulated EZH2, suggesting that ATM status contributes to rewiring the epigenetic landscape of pancreatic tumors, subsequently supporting oncogenic features.

Aims & Methods

To investigate whether and how EZH2 impacts ATM-deficient PDAC pathogenesis, we generated conditional double ATM and EZH2 knockouts in Kras^G12D/+; Ptf1a^Cre/+ mice. In vitro approaches were conducted using primary cell lines isolated from murine endpoint tumors. Additionally, CRISPR/Cas9 strategy was implemented on ATM-deficient cell lines to decipher the ATM-EZH2 molecular axis.

Results

Double-null mice showed extended mouse survival and decreased undifferentiated malignant cell features. Strikingly, interrogation of publicly available human datasets (TCGA, PanCancer Atlas) revealed a significant extended progression-free survival of ATM^neg EZH2^neg PDAC patients compared to ATM^neg EZH2^pos PDAC cases. Furthermore, we identified the histone-methyltransferase EZH2 as a direct ATM substrate impacting the mesenchymal phenotype of ATM-depleted tumors. Interestingly, RNA-seq analysis of ATM-deficient pancreatic cancer cells revealed upregulation of a transcriptomic program associated with cell differentiation upon EZH2 depletion by CRISPR/Cas9 strategy. In line, EZH2 depletion restored differentiated tumor features ex vivo. Further in vitro investigations revealed that ATM status significantly impacts EZH2 activity via a post-translational regulation axis, leading to a fostered tumor supporting EZH2 activity during pancreatic carcinogenesis. Specifically, the ATM kinase activity results in EZH2 ubiquitination and degradation by promoting Cullin1 E3-ubiquitin ligase recruitment. Finally, we demonstrated that a combinatorial therapy involving a potent EZH2 inhibitor promotes genomic instability and exacerbates the cytotoxic effects of PARP interference in ATM-deficient HRD PDAC.

Conclusion

Overall, we show that ATM deficiency significantly impacts EZH2 epigenetic functions and highlight the molecular stratification according to ATM status prior to pharmacological EZH2 interference in PDAC therapies as a valuable approach to target ATM-deficient HRD tumors.

Introduction

The Mediterranean diet identified as a priority because it contributes to the normalization of key metabolic parameters in patients with non-alcoholic fatty liver disease (NAFLD). However, it is necessary to take into account the possibilities of following such a diet and the nutrigenetic characteristics of patients in different regions of the world. Purpose: to study the effect of nutrigenetic parameters in patients with NAFLD on the effectiveness of non-drug treatment.

Aims & Methods

Purpose: to study the effect of nutrigenetic parameters in patients with NAFLD on the effectiveness of non-drug treatment. 105 patients (55 men and 50 women) with NAFLD were examined. In patients, the features of eating disorders (ED) were studied (DEBQ questionnaire), nutrigenetic parameters - 5 polymorphisms: Pro12Ala of the PPARG2 gene (rs1801282), 101027 of the ADRB2 gene (rs1042714) and Arg16Gly of the ADRB2 gene (1010282); (rs4994) and Thr54Ala of the FABP2 gene (rs1799883) associated with the risk of metabolic disorders.

Results

Two polymorphisms associated with disorders of the ED gene (Pro12Ala PPARG2 and Trp64Arg ADRB3) were identified. Sex differences in the frequency of genotypes of the Pro12Ala polymorphism of the PPARG2 gene were not found (pχ2 = 0.90). 83.6% of men and 82.0% of women were carriers of the PPARG2 gene polymorphism (OR=1.10, CI=0.24-4.99) of the Pro12Pro genotype (AB=1.10, men and 16.7% of women of the genotype Pro12Ala (OR = 0.91, OR) = 0.20 - 4.13). The distribution of genotypes and allelic variants of the ADRB3 gene polymorphism had significant differences (px2 = 0.05). The Trp64Trp genotype of the ADRB3 gene polymorphism were found in 80.0% of men and 55.0% of women, the Trp64Arg genotype in 20.0% of men and 32.5% of women, the Arg64Arg genotype was found only in women. An analysis of the distribution of 64Trp and 64Arg alleles by sex using a multiplicative model showed that the significance of the association of the minor female 64Arg allele was confirmed by an odds ratio of 3.13 (CI = 1.01–9.70) versus 0.32 (CI = 0.01–9 .70). 10 - 0.99) for the minor allele. A significant association (px2 = 0.02) of the protective minor allele 12Ala with emotionally restrictive types of ED (OR = 0.11, CI = 0.10 - 0.97) was established, while the external type of oblique ED was associated with the carriage of the main allele polymorphism 12Pro of the Pro12Ala PPARG2 gene (OR = 8.71, CI = 1.03-7.66). Analysis of the distribution of 64Trp and 64Arg alleles depending on the type of EP disorder showed a significant association (px2 = 0.006) of the metabolically unfavorable minor 64Arg allele with the external type of ED disorders (OR = 5.53, CI = 1.48-20.68), while emotional and restrictive types were associated with the carrier of the main 64Trp allele (OR = 0.18, CI = 0.05-0.68). In patients with NAFLD, the external type of ED disorder prevails (p<0.05).

Conclusion

To increase the effectiveness of non-drug treatment, one should take into account nutrigenetic features - the presence of ProARA2 polymorphisms of the PPARG2 gene and Trp64Arg of the ADRB3 gene, which are associated with the peculiarities of nutrient metabolism and malnutrition in patients with NAFLD.

Disclosure

Nothing to disclose

Introduction

96-98% of patients survive acute pancreatitis (AP), but in the post-AP phase, patients are at high risk of morbidity and mortality. It has been shown that pancreatic exocrine insufficiency can occur after AP.

Aims & Methods

We aimed to investigate the rate, risk factors, and the effect of pancreatic enzyme replacement therapy (PERT) for PEI in patients with AP. The study protocol was registered on PROSPERO (CRD42024516403). We conducted a systematic search on 5 February 2024 in three databases (PubMed, EMBASE, and CENTRAL). We included in the analysis studies reporting on risk factors and PERT efficacy in PEI associated with AP. Pooled proportion and odds ratios (OR) with a 95% confidence interval (CI) were calculated using a random effect model.

Results

Fifty-six articles were included in our meta-analysis. Among 17896 patients with AP, the pooled proportion of PEI was 20 % ([CI]: 15–26). The odds of PEI development were two-fold higher in severe acute pancreatitis (OR=2.44, [CI]: 0.98–6.11) compared with mild or moderate AP and three times higher after necrosectomy compared to patients without necrosectomy (OR=3.26, [CI]: 1.6–6.64). There was no significant difference between the odds of PEI among AP patients with necrosis (OR=1.43, [CI]: 0.32–6.45) and those without necrosis. However, the odds of PEI were twice as high in patients with infected necrosis (OR=2.13, [CI]: 0.93–4.87) than in patients with sterile necrosis. Pancreatic enzyme replacement therapy was prescribed for 22% ([CI]: 16–30) of patients after AP.

Conclusion

One in five patients with AP develops PEI. The rate is higher in patients with severe AP, infected necrosis, or who need necrosectomy. Patients with AP should be screened for PEI to allow timely PERT administration.