Cancer cells metabolize different energy sources to generate biomass rapidly. The purine biosynthetic pathway was recently identified as an important source of metabolic intermediates for these processes. However, very little was known about the regulatory mechanisms of purine metabolism in hepatocellular carcinoma (HCC). We explored the role of dual‐specificity tyrosine (Y) phosphorylation–regulated kinase 3 (Dyrk3) in HCC metabolism. Dyrk3 was significantly down‐regulated in HCC compared with normal controls. Its introduction in HCC cells markedly suppressed tumor growth and metastasis in xenograft tumor models. Mass spectrometric analysis of metabolites suggests that the effect of Dyrk3 on HCC occurred at least partially through down‐regulating purine metabolism, as evidenced by the fact that inhibiting purine synthesis reverted the HCC progression mediated by the loss of Dyrk3. We further provide evidence that this action of Dyrk3 knockdown requires nuclear receptor coactivator 3 (NCOA3), which has been shown to be a coactivator of activating transcription factor 4 (ATF4) to target purine pathway genes for transcriptional activation. Mechanistically, Dyrk3 directly phosphorylated NCOA3 at Ser‐1330, disrupting its binding to ATF4 and thereby causing the inhibition of ATF4 transcriptional activity. However, the phosphorylation‐resistant NCOA3‐S1330A mutant has the opposite effect. Interestingly, the promoter activity of Dyrk3 was negatively regulated by ATF4, indicating a double‐negative feedback loop. Importantly, levels of Dyrk3 and phospho‐NCOA3‐S1330 inversely correlate with the expression of ATF4 in human HCC specimens. Conclusion: Our findings not only illustrate a function of Dyrk3 in reprograming HCC metabolism by negatively regulating NCOA3/ATF4 transcription factor complex but also identify NCOA3 as a phosphorylation substrate of Dyrk3, suggesting the Dyrk3/NCOA3/ATF4 axis as a potential candidate for HCC therapy.

Rheumatoid arthritis (RA) is a chronic inflammatory autoimmune disease that primarily affects the joints. Overweight and obesity can aggravate disease activity and clinical outcome in patients with RA. However, the role of bariatric surgery in inducing weight loss in the treatment of RA has not been confirmed. In this 12-month prospective cohort study, RA patients with obesity who were referred to our hospital were included. Thirty-two patients were classified into the bariatric surgery group according to the patient’s decision after a comprehensive assessment of surgery indications, and 33 patients received only pharmacotherapy for RA. At the 12-month follow-up, the response rates of ACR20, ACR50 and ACR70 were 75.0% vs. 51.5%, 53.1% vs. 39.4% and 31.3% vs. 21.2% in the bariatric surgery and non-surgery groups, respectively (all p < 0.05); the mean DAS28-ESR, DAS28-CRP and cDAI scores were 1.5 ± 0.9 vs. 2.4 ± 1.4, 1.2 ± 0.9 vs. 2.2 ± 1.7 and 9.5 ± 6.8 vs. 15.8 ± 12.5, respectively, in surgical patients compared to non-surgical patients (all p < 0.05). Compared to baseline, after 12 months, a significant reduction was observed in the use of leflunomide, biological agents, combination treatments, and NSAIDs in both groups (p < 0.05 or p < 0.01). However, there was no difference in medication use between the 2 groups either at baseline or at the 12-month follow-up (all p > 0.05). Compared to non-surgical patients, in RA patients with obesity, weight loss after bariatric surgery was associated with lower disease activity. Medication tapering for RA in patients who underwent bariatric surgery was not superior to that in non-surgical patients.

Background: Ferroptosis, is characterized by lipid peroxidation of fatty acids in the presence of iron ions, which leads to cell apoptosis. This leads to the disruption of metabolic pathways, ultimately resulting in liver dysfunction. Although ferroptosis is linked to nonalcoholic steatohepatitis (NASH), understanding the key ferroptosis-related genes (FRGs) involved in NASH remains incomplete. NASH may be targeted therapeutically by identifying the genes responsible for ferroptosis. Methods: To identify ferroptosis-related genes and develop a ferroptosis-related signature (FeRS), 113 machine-learning algorithm combinations were used. Results: The FeRS constructed using the Generalized Linear Model Boosting algorithm and Gradient Boosting Machine algorithms exhibited the best prediction performance for NASH. Eight FRGs, with ZFP36 identified by the algorithms as the most crucial, were incorporated into in FeRS. ZFP36 is significantly enriched in various immune cell types and exhibits significant positive correlations with most immune signatures. Conclusion: ZFP36 is a key FRG involved in NASH pathogenesis.

Background: Evidence suggests that hepatocyte mitochondrial dysfunction leads to abnormal lipid metabolism, redox imbalance, and programmed cell death, driving the onset and progression of non-alcoholic steatohepatitis (NASH). Identifying hub mitochondrial genes linked to NASH may unveil potential therapeutic targets. Methods: Mitochondrial hub genes implicated in NASH were identified via analysis using 134 algorithms. Results: The Random Forest algorithm (RF), the most effective among the 134 algorithms, identified three genes: Aldo–keto reductase family 1 member B10 (AKR1B10), thymidylate synthase (TYMS), and triggering receptor expressed in myeloid cell 2 (TREM2). They were upregulated and positively associated with genes promoting inflammation, genes involved in lipid synthesis, fibrosis, and nonalcoholic steatohepatitis activity scores in patients with NASH. Moreover, using these three genes, patients with NASH were accurately categorized into cluster 1, exhibiting heightened disease severity, and cluster 2, distinguished by milder disease activity. Conclusion: These three genes are pivotal mitochondrial genes implicated in NASH progression.