Cells respond to DNA damage by activating a complex array of signaling networks, which include the AMPK and mTOR pathways. After DNA double-strand breakage, ATM, a core component of the DNA repair system, activates the AMPK-TSC2 pathway, leading to the inhibition of the mTOR cascade. Recently, we showed that both AMPK and mTOR interact with SMYD3, a methyltransferase involved in DNA damage response. In this study, through extensive molecular characterization of gastrointestinal and breast cancer cells, we found that SMYD3 is part of a multiprotein complex that is involved in DNA damage response and also comprises AMPK and mTOR. In particular, upon exposure to the double-strand break-inducing agent neocarzinostatin, SMYD3 pharmacological inhibition suppressed AMPK cascade activation and thereby promoted the mTOR pathway, which reveals the central role played by SMYD3 in the modulation of AMPK-mTOR signaling balance during cancer cell response to DNA double-strand breaks. Moreover, we found that SMYD3 can methylate AMPK at the evolutionarily conserved residues Lys411 and Lys424. Overall, our data revealed that SMYD3 can act as a bridge between the AMPK and mTOR pathways upon neocarzinostatin-induced DNA damage in gastrointestinal and breast cancer cells.

Gastric cancer (GC) is the third most deadly cancer worldwide. Considerable efforts have been made to find targetable drivers in order to improve patient outcomes. MET is one of the most important factors involved in GC initiation and progression as it plays a major role in GC invasiveness and is related to cancer stemness. Unfortunately, treatment strategies targeting MET are still limited, with a proportion of patients responding to therapy but later developing resistance. Here, we showed that MET is a molecular partner of the SMYD3 methyltransferase in GC cells. Moreover, we found that SMYD3 pharmacological inhibition affects the HGF/MET downstream signaling pathway. Extensive cellular analyses in GC models indicated that EM127, a novel active site-selective covalent SMYD3 inhibitor, can be used as part of a synergistic approach with MET inhibitors in order to enhance the targeting of the HGF/MET pathway. Importantly, our data were confirmed in a 3D GC cell culture system, which was used as a surrogate to evaluate stemness characteristics. Our findings identify SMYD3 as a promising therapeutic target to impair the HGF/MET pathway for the treatment of GC.

SMDY3 is a histone-lysine N-methyltransferase involved in several oncogenic processes and is believed to play a major role in various cancer hallmarks. Recently, we identified ATM, BRCA2, CHK2, MTOR, BLM, MET, AMPK, and p130 as direct SMYD3 interactors by taking advantage of a library of rare tripeptides, which we first tested for their in vitro binding affinity to SMYD3 and then used as in silico probes to systematically search the human proteome. Here, we used this innovative approach to identify further SMYD3-interacting proteins involved in crucial cancer pathways and found that the chromatin remodeling factors EP300 and TRRAP interact directly with SMYD3, thus linking SMYD3 to the emerging ‘nonmutational epigenetic reprogramming’ cancer hallmark. Of note, we validated these interactions in gastrointestinal cancer cell lines, including HCT-116 cells, which harbor a C-terminal truncating mutation in EP300, suggesting that EP300 binds to SMYD3 via its N-terminal region. While additional studies are required to ascertain the functional mechanisms underlying these interactions and their significance, the identification of two novel SMYD3 interactors involved in epigenetic cancer hallmark pathways adds important pieces to the puzzle of how SMYD3 exerts its oncogenic role.

Background: Metabolic Dysfunction-Associated Steatotic Liver Disease (MASLD) is a cluster of conditions characterized by accumulations of fat, metabolic factors such as obesity, diabetes and high cholesterol. MASLD is now the leading cause of chronic liver disease worldwide, with a rapidly increasing trend. We aimed to demonstrate that genetic variants of rs2802292 SNP can influence the development of MASLD even after many years. Methods: We studied 650 participants from the NUTRIHEP cohort, both at baseline (2005–2006) and at first recall (2014–2018), and genotyped rs2802292. The validated European Prospective Investigation into Cancer and Nutrition (EPIC) questionnaire was administered during the visit, and each single food was assigned to one of 33 groups. Results: Associations of food intake at baseline with MASLD were found in the first recall, for each genotype, GG, GT, and TT, and several covariates were used to adjust models. Dressing fats other than olive oil resulted protection against MASLD in GG subjects, whereas seed oil, juices, and spirits resulted in protection against MASLD for GT subjects. An increased risk of MASLD was found for subjects with the TT genotype for white meat intake (OR = 1.018, p = 0.031, 1.002 to 1.035 95% C.I.), ready-to-eat dishes (OR = 1.015, p = 0.033, 1.001 to 1.029 95% C.I.), processed meat (OR = 1.093, p = 0.003, 1.031 to 1.158 95% C.I.), and processed fish (OR = 1.085, p = 0.037, 1.005 to 1.172 95% C.I.). Conclusions: Subjects with the TT genotype had a higher risk of developing MASLD than subjects with other genotypes. A healthier lifestyle is important to counteract liver disease.

Pancreatic ductal adenocarcinoma (PDAC) is one of the most lethal malignancies, and approximately 15% of cases arise from intraductal papillary mucinous neoplasms (IPMNs). These precursor lesions can progress to invasive cancer through the accumulation of molecular alterations. To identify pathways associated with this transition, we performed comparative transcriptomic analyses of patient-derived IPMN and PDAC samples, followed by protein-level validation in tissue specimens and pancreatic cancer cell lines. Functional studies were conducted using the selective p38α inhibitor ralimetinib in two-dimensional cultures, three-dimensional tumorspheres, and patient-derived tumor organoids (PDTOs). Transcriptomic profiling revealed significant downregulation of the p38 pathway in IPMNs compared with PDAC, suggesting progressive pathway activation during pancreatic tumorigenesis. Immunohistochemical analyses confirmed increased phospho-activated p38α in PDAC tissues, particularly in lesions with advanced malignant features, while PDAC cell lines displayed higher levels of activated p38α than non-tumorigenic pancreatic epithelial cells. Pharmacological inhibition of p38α suppressed downstream MAPKAPK2 phosphorylation, induced apoptotic cell death, and reduced tumorsphere growth and viability. Consistently, PDTOs exhibiting elevated p38α activation showed increased sensitivity to ralimetinib treatment. Collectively, these findings identify p38α signaling as a pathway activated during PDAC progression and support further investigation of p38α-targeted therapies as a potential precision medicine strategy for pancreatic cancer.

The LPIN1 rs13412852 variant has been linked to lipid levels and liver disease in children. This genotype may modulate the liver’s response to sedentary behaviour, potentially increasing the vulnerability of certain individuals to liver dysfunction. These findings underscore the need to consider both genetic predisposition and environmental exposures when evaluating disease risk. This study aims to investigate the association between the LPIN rs13412852 T-allele and sedentary behaviour and to explore how the interplay between genetic and environmental factors may contribute to individual susceptibility to liver-related conditions. rs13412852 was genotyped in a cohort from Southern Italy (n = 394), and all participants were administered an International Physical Activity Questionnaire (IPAQ), collected a blood sample, and underwent an abdominal ultrasound analysis. The association between metabolic dysfunction-associated steatotic liver disease (MASLD), rs13412852, and sedentary behaviour, alone and together with interaction, was studied. The results indicated a statistical association on MASLD, of rs13412852, and sedentary levels (OR = 1.80, 1.06 to 3.05 95% C.I., p = 0.03, and OR = 1.72, 1.13 to 2.64 95% C.I.), respectively, and also with interaction between moderate or sever sedentary level and T-carrier (OR = 2.99, 1.39 to 6.45 95% C.I., p = 0.005) adjusted for some covariates. The risk of MASLD was highest among individuals with both moderate/severe sedentary behaviour and the CT/TT genotype, suggesting a potential synergistic effect. These findings establish LPIN1 as both a physiological gatekeeper and a genetic susceptibility locus, with its influence subject to modification via behavioural treatments.