Zelin Cui

Abstract Cuproptosis, caused by excessively high copper concentrations, is urgently exploited as a potential cancer therapeutic. However, the mechanisms underlying the initiation, propagation, and ultimate execution of cuproptosis in tumors remain unknown. Here, we show that copper content is significantly elevated in gastric cancer (GC), especially in malignant tumors. Screening reveals that METTL16, an atypical methyltransferase, is a critical mediator of cuproptosis through the m 6 A modification on FDX1 mRNA. Furthermore, copper stress promotes METTL16 lactylation at site K229 followed by cuproptosis. The process of METTL16 lactylation is inhibited by SIRT2. Elevated METTL16 lactylation significantly improves the therapeutic efficacy of the copper ionophore– elesclomol. Combining elesclomol with AGK2, a SIRT2-specific inhibitor, induce cuproptosis in gastric tumors in vitro and in vivo. These results reveal the significance of non-histone protein METTL16 lactylation on cuproptosis in tumors. Given the high copper and lactate concentrations in GC, cuproptosis induction becomes a promising therapeutic strategy for GC.

BACKGROUND: An increasing number of studies have implicated the microbiome in certain diseases, especially chronic diseases. In this study, the bacterial communities in the sputum of pulmonary tuberculosis patients were explored. Total DNA was extracted from sputum samples from 31 pulmonary tuberculosis patients and respiratory secretions of 24 healthy participants. The 16S rRNA V3 hyper-variable regions were amplified using bar-coded primers and pyro-sequenced using Roche 454 FLX. RESULTS: The results showed that the microbiota in the sputum of pulmonary tuberculosis patients were more diverse than those of healthy participants (p<0.05). The sequences were classified into 24 phyla, all of which were found in pulmonary tuberculosis patients and 17 of which were found in healthy participants. Furthermore, many foreign bacteria, such as Stenotrophomonas, Cupriavidus, Pseudomonas, Thermus, Sphingomonas, Methylobacterium, Diaphorobacter, Comamonas, and Mobilicoccus, were unique to pulmonary tuberculosis patients. CONCLUSIONS: This study concluded that the microbial composition of the respiratory tract of pulmonary tuberculosis patients is more complicated than that of healthy participants, and many foreign bacteria were found in the sputum of pulmonary tuberculosis patients. The roles of these foreign bacteria in the onset or development of pulmonary tuberculosis should be considered by clinicians.

Abstract Mortality rates due to lung cancer are high worldwide. Although PD‐1 and PD‐L1 immune checkpoint inhibitors boost the survival of patients with non‐small‐cell lung cancer (NSCLC), resistance often arises. The Warburg Effect, which causes lactate build‐up and potential lysine‐lactylation (Kla), links immune dysfunction to tumor metabolism. The role of non‐histone Kla in tumor immune microenvironment and immunotherapy remains to be clarified. Here, global lactylome profiling and metabolomic analyses of samples from patients with NSCLC is conducted. By combining multi‐omics analysis with in vitro and in vivo validation, that intracellular lactate promotes extracellular lipolysis through lactyl‐APOC2 is revealed. Mechanistically, lactate enhances APOC2 lactylation at K70, stabilizing it and resulting in FFA release, regulatory T cell accumulation, immunotherapy resistance, and metastasis. Moreover, the anti‐APOC2 K70‐lac antibody that sensitized anti‐PD‐1 therapy in vivo is developed. This findings highlight the potential of anti lactyl‐APOC2‐K70 approach as a new combination therapy for sensitizing immunotherapeutic responses.

Allergic diseases are characterized by the increased serum levels of total IgE and specific IgE against common allergens.1 After sensitization of susceptible individuals, the synthesis and binding of allergen-specific IgE to mast cells (MCs) via high-affinity IgE receptors (FcεRI), atopic individuals respond to allergens by releasing mast cell–derived mediators.2 Secreted by multiple cell types including MCs, exosomes are nano-sized, cell membrane–surrounded structures harboring a broad range of biomolecules linked to cell type–associated functions.