ATP production under lockdown: Cellular processes must respond to change, often by speeding up, slowing down, or stopping altogether. Adenosine triphosphate (ATP) synthases use a transmembrane proton gradient to produce ATP, but this reaction can go in reverse and needs to be halted when conditions are unfavorable. Jinke Gu et al. purified a tetrameric ATP synthase complex from pig hearts that contained the endogenous inhibitory protein IF1. Targeted refinement yielded high-resolution views of the mammalian ATP synthase trapped in two different rotation states by IF1. The findings suggest that ATP synthase tetramers can be inhibited by at least three different mechanisms. Science , this issue p. 1068

NKCC and KCC transporters mediate coupled transport of Na⁺+K⁺+Cl⁻ and K⁺+Cl⁻ across the plasma membrane, thus regulating cell Cl⁻ concentration and cell volume and playing critical roles in transepithelial salt and water transport and in neuronal excitability. The function of these transporters has been intensively studied, but a mechanistic understanding has awaited structural studies of the transporters. Here, we present the cryo-electron microscopy (cryo-EM) structures of the two neuronal cation-chloride cotransporters human NKCC1 (SLC12A2) and mouse KCC2 (SLC12A5), along with computational analysis and functional characterization. These structures highlight essential residues in ion transport and allow us to propose mechanisms by which phosphorylation regulates transport activity.

Biomolecular condensates are droplet-like membrane-less compartments in cells that can sequester proteins. Modulating these condensates offers a promising way to durably inhibit disease-driving proteins that lack enzymatic activity and thus elude traditional drug targeting. However, many such proteins remain beyond the reach of current condensate-modulating strategies. Here we show an alternative approach: by destabilizing target proteins, we directly induce their liquid–liquid phase separation (LLPS), causing them to form condensates. Using this strategy, we develop a small molecule RQ that forces β-catenin (an oncogenic protein in liver cancer) into cytoplasmic condensates. This sequestration prevents β-catenin from entering the nucleus and activating cancer-promoting genes. In nanoparticle form (albumin-bound Abroquinone), RQ is selectively taken up by β-catenin-driven liver cancer cells and kills them while sparing normal cells. This approach suppresses β-catenin-driven tumor growth and overcomes immune evasion, demonstrating a promising paradigm for targeting previously untargetable proteins by inducing their phase separation.

Non-small cell lung cancer (NSCLC) has shown limited response to immunotherapy, primarily due to an immunosuppressive tumor microenvironment characterized by hypoxia and lipid raft formation, which together inhibit T-cell infiltration and function, impeding effective immune responses. To address these challenges, we developed Abstatin, an albumin-bound fluvastatin formulation that targets lipid raft disruption and mitochondrial respiration inhibition, aiming to reduce hypoxia and destabilize lipid rafts to enhance T-cell activity within the tumor. Using bioinformatics analysis, in vitro assays, and in vivo studies in both murine and humanized PDX models, we demonstrated that Abstatin reprograms the NSCLC microenvironment by concurrently lowering hypoxia levels and lipid raft integrity, thereby restoring T-cell infiltration, enhancing cytotoxic T-cell function, and ultimately improving response to Anti-PD-1 therapy. Results showed that Abstatin significantly amplifies Anti-PD-1 efficacy with minimal toxicity, indicating a favorable safety profile for clinical use. This study highlights Abstatin as a promising immunotherapy adjuvant that addresses critical barriers in NSCLC by modulating metabolic pathways linked to immune resistance. Abstatin's approach, which combines modulation of cellular metabolism with immune sensitization, broadens the potential of immunotherapy and provides a practical, scalable strategy to enhance treatment outcomes in NSCLC and potentially other tumors, offering insights into combinatory cancer therapies.

Introduction: Hypoxia is associated with unfavorable prognoses in melanoma patients, and the limited response rates of patients to PD-1/PD-L1 blockade could be attributed to the immunosuppressive tumor microenvironment induced by hypoxia. Exercise offers numerous benefits in the anti-tumor process and has the potential to alleviate hypoxia; however, the precise mechanisms through which it exerts its anti-tumor effects remain unclear, and the presence of synergistic effects with PD-1/PD-L1 immunotherapy is yet to be definitively established.Methods: We established a B16F10 homograft malignant melanoma model and implemented two distinct exercise treatments (low/moderate-intensity swim) based on the mice’s exercise status. The specific function manner of exercise-induced anti-tumor effects was determined through RNA sequencing and analysis of changes in the tumor microenvironment. Furthermore, moderate-intensity swim that exhibited superior tumor suppression effects was combined with Anti-PD-1 treatment to evaluate its in vivo efficacy in mouse models.Results: Exercise intervention yielded a considerable effect in impeding tumor growth and promoting apoptosis. Immunohistochemistry and RNA sequencing revealed improvements in tumor hypoxia and down-regulation of hypoxia-related pathways. Cellular immunofluorescence and ELISA analyses demonstrated a notable increase of cytotoxic T cell amount and a decrease of regulatory T cells, indicating an improvement of tumor immune microenvironment. In comparison to Anti-PD-1 monotherapy, tumor suppressive efficacy of exercise combination therapy was found to be enhanced with improvements in both the hypoxic tumor microenvironment and T cell infiltration.Conclusion: Exercise has the potential to function as a hypoxia modulator improving the tumor immune microenvironment, resulting in the promotion of anti-tumor efficacy and the facilitation of biologically safe sensitization of PD-1/PD-L1 immunotherapy.