Metastasis serves as an indicator of malignancy and is a biological characteristic of carcinomas. Epithelial–mesenchymal transition (EMT) plays a key role in the promotion of tumor invasion and metastasis and in the enhancement of tumor cell aggressiveness. Prostaglandin E synthase 3 (p23) is a cochaperone for heat shock protein 90 (HSP90). Our previous study showed that p23 is an HSP90-independent transcription factor in cancer-associated inflammation. The effect and mechanism of action of p23 on lung cancer metastasis are tested in this study. By utilizing cell models in vitro and mouse tail vein metastasis models in vivo, the results provide solid evidence that p23 is critical for promoting lung cancer metastases by regulating downstream CXCL1 expression. Rather than acting independently, p23 forms a complex with RNA-binding motif protein 14 (RBM14) to facilitate EMT progression in lung cancer. Therefore, our study provides evidence for the potential role of the RBM14–p23–CXCL1–EMT axis in the metastasis of lung cancer.

The coinfection of respiratory viruses and bacteria is a major cause of morbidity and mortality worldwide, despite the development of vaccines and powerful antibiotics. As a macromolecule that is difficult to absorb in the gastrointestinal tract, a homogeneous polysaccharide from Houttuynia cordata (HCPM) has been reported to exhibit anti-complement properties and alleviate influenza A virus (H1N1)-induced lung injury; however, the effects of HCPM without in vitro antiviral and antibacterial activities on more complicated pulmonary diseases resulting from viral-bacterial coinfection remains unclear. This study established a representative coinfection murine pneumonia model infected with H1N1 (0.2 LD₅₀) and methicillin-resistant Staphylococcus aureus (MRSA, 10⁷ CFU). HCPM significantly improved survival rate and weight loss, and ameliorated gut–lung damage and inflammatory cytokine production. Interestingly, the therapeutic effect of HCPM on intestinal damage preceded that in the lungs. Mechanistically, HCPM inhibited the overactivation of the intestinal complement (C3a and C5a) and suppressed the activation of the NLR family pyrin domain-containing 3 (NLRP3) pathway, which contributes to the regulation of the Treg/Th17 cell balance in the gut–lung axis. The results indicate the beneficial effects of an anti-complement polysaccharide against viral–bacterial coinfection pneumonia by modulating crosstalk between multiple immune regulatory networks.

Chemotherapy is currently the mainstay of systemic management for triple-negative breast cancer (TNBC), but chemoresistance significantly impacts patient outcomes. Our research indicates that Doxorubicin (Dox)-resistant TNBC cells exhibit increased glycolysis and ATP generation compared to their parental cells, with this metabolic shift contributing to chemoresistance. We discovered that ALKBH3, an m¹A demethylase enzyme, is crucial in regulating the enhanced glycolysis in Dox-resistant TNBC cells. Knocking down ALKBH3 reduced ATP generation, glucose consumption, and lactate production, implicating its involvement in mediating glycolysis. Further investigation revealed that aldolase A (ALDOA), a key enzyme in glycolysis, is a downstream target of ALKBH3. ALKBH3 regulates ALDOA mRNA stability through m¹A demethylation at the 3′-untranslated region (3′UTR). This methylation negatively affects ALDOA mRNA stability by recruiting the YTHDF2/PAN2–PAN3 complex, leading to mRNA degradation. The ALKBH3/ALDOA axis promotes Dox resistance both in vitro and in vivo. Clinical analysis demonstrated that ALKBH3 and ALDOA are upregulated in breast cancer tissues, and higher expression of these proteins is associated with reduced overall survival in TNBC patients. Our study highlights the role of the ALKBH3/ALDOA axis in contributing to Dox resistance in TNBC cells through regulation of ALDOA mRNA stability and glycolysis.

Acute kidney injury (AKI) has high morbidity and mortality, but effective clinical drugs and management are lacking. Previous studies have suggested that macrophages play a crucial role in the inflammatory response to AKI and may serve as potential therapeutic targets. Emerging evidence has highlighted the importance of forkhead box protein O1 (FoxO1) in mediating macrophage activation and polarization in various diseases, but the specific mechanisms by which FoxO1 regulates macrophages during AKI remain unclear. The present study aimed to investigate the role of FoxO1 in macrophages in the pathogenesis of AKI. We observed a significant upregulation of FoxO1 in kidney macrophages following ischemia–reperfusion (I/R) injury. Additionally, our findings demonstrated that the administration of FoxO1 inhibitor AS1842856-encapsulated liposome (AS-Lipo), mainly acting on macrophages, effectively mitigated renal injury induced by I/R injury in mice. By generating myeloid-specific FoxO1-knockout mice, we further observed that the deficiency of FoxO1 in myeloid cells protected against I/R injury-induced AKI. Furthermore, our study provided evidence of FoxO1’s pivotal role in macrophage chemotaxis, inflammation, and migration. Moreover, the impact of FoxO1 on the regulation of macrophage migration was mediated through RhoA guanine nucleotide exchange factor 1 (ARHGEF1), indicating that ARHGEF1 may serve as a potential intermediary between FoxO1 and the activity of the RhoA pathway. Consequently, our findings propose that FoxO1 plays a crucial role as a mediator and biomarker in the context of AKI. Targeting macrophage FoxO1 pharmacologically could potentially offer a promising therapeutic approach for AKI.

The pathogenesis of pulmonary fibrosis (PF) is complex. It is characterized by myofibroblast hyperplasia and deposition of collagen protein. Indoleamine 2,3-dioxygenase 1 (IDO1) is expressed in lung fibroblasts and epithelial cells, but its functions in lung homeostasis and diseases remain elusive. Here, we characterize the critical role of IDO1 in PF patients and bleomycin (BLM)-induced PF mouse models. We find that IDO1 is significantly upregulated in the fibrotic lungs of patients and mice, showing a positive correlation with genes characteristic of fibrosis. Functionally, IDO1 knockout inhibits lung fibroblast proliferation, differentiation, mitochondrial biogenesis, and mitochondrial oxidative phosphorylation. Conversely, IDO1 overexpression and accumulation of kynurenine (Kyn) exacerbate progressive lung fibrosis. Mechanistically, IDO1-deletion activated profound mitochondrial fusion-enhanced potentially the capacity for fatty acid oxidation, along with activation of de novo glycolytic serine/glycine synthesis pathways and mitochondrial one-carbon metabolism. Wedelolactone (WEL), a small molecule IKK inhibitor, is found to strongly bind to IDO1 and effectively protect mice from PF in an IDO1-dependent manner. Collectively, this study characterizes a promotor role for IDO1 in PF and suggests a potential avenue of targeting IDO1 to treat lung diseases.

Ovarian tumor (OT) is the most lethal form of gynecologic malignancy, with minimal improvements in patient outcomes over the past several decades. Metastasis is the leading cause of ovarian cancer-related deaths, yet the underlying mechanisms remain poorly understood. Psychological stress is known to activate the glucocorticoid receptor (NR3C1), a factor associated with poor prognosis in OT patients. However, the precise mechanisms linking NR3C1 signaling and metastasis have yet to be fully elucidated. In this study, we demonstrate that chronic restraint stress accelerates epithelial–mesenchymal transition (EMT) and metastasis in OT through an NR3C1-dependent mechanism involving nuclear protein 1 (NUPR1). Mechanistically, NR3C1 directly regulates the transcription of NUPR1, which in turn increases the expression of snail family transcriptional repressor 2 (SNAI2), a key driver of EMT. Clinically, elevated NR3C1 positively correlates with NUPR1 expression in OT patients, and both are positively associated with poorer prognosis. Overall, our study identified the NR3C1/NUPR1 axis as a critical regulatory pathway in psychological stress-induced OT metastasis, suggesting a potential therapeutic target for intervention in OT metastasis.

The PA-PB1 interface of the influenza polymerase is an attractive site for antiviral drug design. In this study, we designed and synthesized a mini-library of indazole-containing compounds based on rational structure-based design to target the PB1-binding interface on PA. Biological evaluation of these compounds through a viral yield reduction assay revealed that compounds 27 and 31 both had a low micromolar range of the half maximal effective concentration (EC₅₀) values against A/WSN/33 (H1N1) (8.03 μmol/L for 27; 14.6 μmol/L for 31), while the most potent candidate 24 had an EC₅₀ value of 690 nM. Compound 24 was effective against different influenza strains including a pandemic H1N1 strain and an influenza B strain. Mechanistic studies confirmed that compound 24 bound PA with a K_d which equals to 1.88 μmol/L and disrupted the binding of PB1 to PA. The compound also decreased the lung viral titre in mice. In summary, we have identified a potent anti-influenza candidate with potency comparable to existing drugs and is effective against different viral strains. The therapeutic options for influenza infection have been limited by the occurrence of antiviral resistance, owing to the high mutation rate of viral proteins targeted by available drugs. To alleviate the public health burden of this issue, novel anti-influenza drugs are desired. In this study, we present our discovery of a novel class of indazole-containing compounds which exhibited favourable potency against both influenza A and B viruses. The EC₅₀ of the most potent compounds were within low micromolar to nanomolar concentrations. Furthermore, we show that the mouse lung viral titre decreased due to treatment with compound 24. Thus our findings identify promising candidates for further development of anti-influenza drugs suitable for clinical use.

Chronic kidney disease (CKD) affects 8%–15% of the population globally and can cause renal failure, partly due to lack of effective treatments and drug targets. Three novel cembrane diterpenoids papyifurans A‒C (1–3), in particular of 1 with an unprecedented trioxatetracyclo[10.2.1.1^2,5.1^6,9]heptadecane polyether scaffold, derived from Boswellia papyrifera resin, were found to effectively protect against renal fibrosis in vitro and in vivo. Their structures were fully characterized using a combination of spectroscopic, computational, modified Mosher’s, and X-ray crystallographic analysis. In particular, we performed chemical proteomic analyses and found that Elongation factor 2 (EEF2) is the key target of compound 1 for anti-renal fibrosis in vitro. Moreover, previous studies have linked EEF2 with lung fibrosis, while compound 1 was found to inhibit the hallmarks of organ fibrosis in vitro. Such effects were observed to decrease with the knock down of EEF2 in vitro, suggesting that EEF2 might be a universal drug target of organ fibrosis. Collectively, the present study demonstrated an example of identifying drug targets by using structurally novel natural products, which will be beneficial for developing therapeutic agents against organ fibrosis.

Metastasis is the leading cause of death from cutaneous melanoma. Identifying metastasis-related targets and developing corresponding therapeutic strategies are major areas of focus. While functional genomics strategies provide powerful tools for target discovery, investigations at the protein level can directly decode the bioactive epitopes on functional proteins. Aptamers present a promising avenue as they can explore membrane proteomes and have the potential to interfere with cell function. Herein, we developed a target and epitope discovery platform, termed functional aptamer evolution-enabled target identification (FAETI), by integrating affinity aptamer acquisition with phenotype screening and target protein identification. Utilizing the aptamer XH3C, which was screened for its migration-inhibitory function, we identified the Chondroitin Sulfate Proteoglycan 4 (CSPG4), as a potential target involved in melanoma migration. Further evidence demonstrated that XH3C induces cytoskeletal rearrangement by blocking the interaction between the bioactive epitope of CSPG4 and integrin α4. Taken together, our study demonstrates the robustness of aptamer-based molecular tools for target and epitope discovery. Additionally, XH3C is an affinity and functional molecule that selectively binds to a unique epitope on CSPG4, enabling the development of innovative therapeutic strategies.

Effective annotation of in vivo drug metabolites using liquid chromatography-mass spectrometry (LC–MS) remains a formidable challenge. Herein, a metabolic reaction-based molecular networking (MRMN) strategy is introduced, which enables the “one-pot” discovery of prototype drugs and their metabolites. MRMN constructs networks by matching metabolic reactions and evaluating MS² spectral similarity, incorporating innovations and improvements in feature degradation of MS² spectra, exclusion of endogenous interference, and recognition of redundant nodes. A minimum 75% correlation between structural similarity and MS² similarity of neighboring metabolites was ensured, mitigating false negatives due to spectral feature degradation. At least 79% of nodes, 49% of edges, and 97% of subnetworks were reduced by an exclusion strategy of endogenous ions compared to the Global Natural Products Social Molecular Networking (GNPS) platform. Furthermore, an approach of redundant ions identification was refined, achieving a 10%–40% recognition rate across different samples. The effectiveness of MRMN was validated through a single compound, plant extract, and mixtures of multiple plant extracts. Notably, MRMN is freely accessible online at https://yaolab.network, broadening its applications.