Journal of Clinical Investigation最新文献

Chronic stress triggers a range of physiological responses that could dysregulate the immune system and metabolic processes, thereby increasing susceptibility to various diseases. In this issue of the JCI, Wu et al. identified a metabolic bridge between chronic stress and liver cancer progression. Chronic stress-induced glucocorticoids promoted aminopeptidase N (ANPEP) expression and subsequent reprogramming of amino acid metabolism, leading to increased liver cancer growth and metastasis. ANPEP facilitated stabilization of the cystine-glutamate transporter system Xc- and increased l-cystine influx, thereby enhancing cellular antioxidant capacity to prevent ferroptosis. Silencing ANPEP in combination with sorafenib treatment showed a synergistic inhibitory effect on liver cancer progression. These findings uncover ANPEP as a valuable target for therapeutic interventions to treat patients with liver cancer experiencing chronic stress.

Checkpoint inhibitor-associated autoimmune diabetes (CIADM) is a life-altering and potentially life-threatening complication of immune checkpoint inhibitor (ICI) treatment in patients with cancer. Risk factors and predictors of this complication remain largely unknown. In this issue of the JCI, Wu et al. examined serum and PBMCs from 14 ICI-treated patients who developed CIADM and 28 matched controls. They identified several variables that were present prior to ICI treatment, including reduced pancreatic volume, islet autoantibodies, and biomarkers indicating immune cell activation, that together are highly predictive of development of CIADM. These findings could have profound clinical implications including treatment decisions, monitoring, and potential future prevention strategies.

Glucagon-like peptide-1 receptor agonists (GLP-1RAs), established therapies for type 2 diabetes and obesity, are increasingly recognized for their potential in neurodegenerative diseases. Preclinical studies across diverse neurodegenerative conditions consistently demonstrate neuroprotective effects of GLP-1RAs, including reduced protein aggregation, enhanced autophagy, improved mitochondrial function, suppression of neuroinflammation, and preservation of synaptic integrity. Epidemiological analyses further suggest reduced incidence of dementia, Parkinson disease, and multiple sclerosis among long-term GLP-1RA users. Early human trials provide signals of target engagement, such as preserved cerebral glucose metabolism, altered inflammatory biomarkers, and slowed brain atrophy, although clinical outcomes to date remain mixed and trials in rarer disorders are sparse. Translation is constrained by uncertainty around optimal molecule choice, CNS penetrance, tolerability, adherence, and heterogeneity of response. Furthermore, next-generation dual and triple agonists may offer enhanced efficacy but remain untested in neurodegeneration. Conceptually, GLP-1RAs share pleiotropic effects with exercise - one of the few interventions with proven disease-modifying potential - by enhancing insulin signaling, stabilizing mitochondria, reducing inflammation, and promoting synaptic plasticity. This overlap highlights their promise as "pharmacological analogues of exercise," and underscores the need for biomarker-driven, disease-specific trials to establish whether GLP-1RAs can deliver durable disease modification across the spectrum of neurodegenerative diseases.

Germline loss-of-function folliculin (FLCN) gene mutations cause Birt-Hogg-Dubé (BHD) syndrome, in which pulmonary cysts are present in up to 90% of the patients. The pathogenic mechanisms underlying lung cyst development in BHD are almost entirely unknown because of the limited availability of BHD patient lung samples and the lack of authentic BHD lung disease models. We generated lung mesenchyme-specific and lung epithelium-specific Flcn-knockout mice using a Cre/loxP approach. We found that deletion of Flcn in lung mesenchymal cells, but not in lung epithelial cells, resulted in alveolar enlargement starting from early postnatal life, with evidence of cyst formation in adult mice, resembling the pulmonary disease in human BHD. These changes were associated with increased mechanistic target of rapamycin complex 1 (mTORC1) activity in the lungs of both patients with BHD and Flcn-knockout mice. Attenuation of mTORC1 activity by knocking out Raptor gene (Rptor) or pharmacologic inhibition using rapamycin substantially rescued the pulmonary pathology caused by Flcn deletion in mice. Taken together, these human and mouse data support a model in which mTORC1 hyperactivation drives pulmonary cystic pathology in BHD.

Anaphylaxis is a life-threatening hypersensitivity reaction. Clinical observations suggest heightened susceptibility during viral infections, yet the mechanisms remain poorly defined. Here, we show that both active and passive IgG-mediated anaphylaxis were exacerbated in the setting of acute viral infection. In mice, this enhancement was driven predominantly by FcγRIV, the homolog of human FcγRIIIa. FcγRIV crosslinking induced anaphylactic symptoms selectively in infected animals, with no effect in naive conditions. Among leukocytes, inflammatory monocytes emerged as the principal drivers of this lethal reaction. Viral infection triggered a strong upregulation of FcγRIV on inflammatory monocytes, an effect absent in type I IFN receptor-deficient (Ifnar1-deficient) mice. Extending these findings, we observed increased frequencies of CD16-expressing classical monocytes in patients with acute COVID-19, and murine SARS-CoV-2 infection recapitulated this phenotype. Mechanistically, FcγRIV crosslinking during infection promoted the production of platelet-activating factor, the key mediator of mortality, in a type I IFN-dependent (IFN-I-dependent) manner. Together, these findings indicate that viral infection creates an immune milieu that heightens monocyte sensitivity to Fcγ receptor engagement, positioning these cells as major effectors of IgG-mediated hypersensitivity in the infected host. They further suggest that Fc receptor pathway modulation merits further investigation in contexts with heightened IFN-I responses, such as in systemic lupus erythematosus.

The approval of sotorasib and adagrasib as the first KRAS G12C inhibitors has made the RAS oncogene a druggable target. However, they have modest objective response rates and short response durations. Therefore, strategies for improving RAS-targeted cancer therapy are urgently needed. Here, we found that both sotorasib and adagrasib promoted topoisomerase IIα (Topo IIα) proteasomal degradation in KRAS G12C-mutant cancer cells and induced DNA damage and apoptosis. In cell lines with acquired resistance to sotorasib, elevated Topo IIα levels were detected. TOP2A overexpression in sensitive KRAS G12C-mutant cells conferred resistance to sotorasib, whereas TOP2A knockdown in sotorasib-resistant cell lines sensitized the cells to sotorasib. Moreover, the combination of a KRAS G12C inhibitor such as sotorasib with a Topo II inhibitor such as VP-16 synergistically decreased the survival of sotorasib-resistant RAS G12C-mutant cells with augmented induction of DNA damage and apoptosis, effectively inhibited the growth of sotorasib-resistant tumors, and delayed or prevented the emergence of acquired resistance to sotorasib in vivo. Collectively, our results reveal an essential role of Topo IIα inhibition in mediating the therapeutic efficacy of RAS-targeted cancer therapy, providing a strong scientific rationale for targeting Topo II to improve RAS-targeted cancer therapies.

Broadly neutralizing antibodies (bnAbs) are evaluated as possible alternatives to standard antiretroviral treatment (ART) for maintaining control of HIV-1 replication and may enhance immune responses to reduce or control the viral reservoir. However, the immunological and virological effects of bnAbs in infants and children are unknown. We conducted a detailed analysis of proviral reservoir dynamics and antiviral immune responses in a unique group of young children from Botswana who started ART at birth and then stopped standard ART while receiving the bnAbs 10-1074 and VRC01-LS in a subsequent clinical trial. No quantitative changes in frequencies of proviral sequences were observed during bnAb treatment, but selection of genome-intact proviruses in transcriptionally repressive heterochromatin regions occurred in some study participants. Faster viral rebound following standard ART cessation was linked to elevated proportions of KIR2DL1-positive NK cells. In contrast, delayed viral rebound and more limited viral reservoir size were associated with elevated proportions of NKG2A-positive NK cells and with the HLA-B-21M signal peptide polymorphism. HIV-specific T cell responses were low in all study participants and unrelated to viral reservoir sizes or clinical outcomes following ART interruption. These results suggest that, in young children, specific NK cell subsets and KIR-HLA interactions might be linked to HIV-1 rebound kinetics after substitution of standard ART with bnAbs.