Metabolic Reprogramming of Klebsiella pneumoniae Exposed to Serum and Its Potential Implications in Host Immune System Evasion and Resistance.

The aim of this study was to identify, using proteomics, the molecular alterations caused by human serum exposure to Klebsiella pneumoniae ACH2. The analysis was performed under two different conditions, native serum from healthy donors and heat-inactivated serum (to inactivate the complement system), and at two different times, after 1 and 4 h of serum exposure. More than 1,000 bacterial proteins were identified at each time point. Enterobactin, a siderophore involved in iron uptake, and proteins involved in translation were upregulated at 1 h, while the chaperone ProQ and the glyoxylate cycle were identified after 4 h. Enzymes involved in the stress response were downregulated, and the SOD activity was validated using an enzymatic assay. In addition, an intricate metabolic adaptation was observed, with pyruvate and thiamine possibly involved in survival and virulence in the first hour of serum exposure. The addition of exogenous thiamine contributes to bacterial growth in human serum, corroborating this result. During 4 h of serum exposure, the glyoxylate cycle (GC) probably plays a central role, and the addition of exogenous succinate suppresses the GC, inducing a decrease in serum resistance. Therefore, serum exposure causes important changes in iron acquisition, the expression of virulence factors, and metabolic reprogramming, which could contribute to bacterial serum resistance.

Overexpression of the key metabolic protein Carnitine Palmitoyl Transferase 1A (CPT1A) in equine sarcoid.

The equine sarcoid is the most common skin neoplasia of fibroblastic origin in horses, characterized by an excessive accumulation of extracellular matrix produced by sarcoid fibroblasts under hypoxic condition. Neoplastic cells can adapt to hypoxia by using alternative energy sources, particularly those that arise from fatty acid oxidation (FAO). The Carnitine Palmitoyl Transferase 1A (CPT1A) belongs to Carnitine System (CS) and promotes the entrance of fatty acids into the mitochondria for ß-oxidation. In this study, CPT1A expression was comparatively addressed in 25 equine sarcoids and 5 normal skin samples using immunohistochemistry (IHC). Specificity of CPT1A antibody was validated by Western Blotting (WB). In normal skin samples IHC staining was weak and mainly confined to basal epidermis and few dermal fibroblasts. Sarcoid fibroblast exhibited a strong cytoplasmic and nuclear signal in 60% of the tumor samples. Cytoplasmic CPT1A expression in sarcoid fibroblasts indicates that the protein is actively involved in metabolic reprogramming processes. Nuclear CPT1A expression suggests that the protein may also be involved in the regulation of neoplastic proliferation.

Selenoprotein o as a regulator of macrophage metabolism in selenium deficiency-induced lung inflammation.

Selenium (Se) deficiency induces an inflammatory response in the lungs, but the underlying mechanisms are unknown. Selenoprotein O (SelO) is the largest selenoprotein in terms of molecular weight, yet its potential biological functions have yet to be characterized. Our study revealed that Se deficiency leads to an imbalance in the expression of pro-inflammatory "M1" macrophages and anti-inflammatory "M2" macrophages in alveolar macrophages (AMs) and interstitial macrophages (IMs) and contributed to the development of lung inflammation. Through the analysis of differentially expressed selenoproteins, we identified SelO as a potential regulator of the imbalance in pulmonary macrophage polarization caused by Se deficiency. In vitro experiments showed that SelO knockdown enhanced the polarization of M1 macrophages while suppressing that of M2 macrophages. In addition, SelO knockdown reprogrammed macrophage metabolism to glycolysis, disrupting oxidative phosphorylation (OXPHOS). Mechanistically, SelO primarily targets mitochondrial transcription factor A (TFAM), which plays a crucial role in the transcription and replication of mitochondrial DNA (mtDNA) and is essential for mitochondrial biogenesis and energy metabolism. The deficiency of SelO affects TFAM, resulting in its uncontrolled degradation, which compromises mitochondrial function and energy metabolism. In summary, the findings presented here offer significant theoretical insights into the physiological functions of SelO.

CALB2 drives pancreatic cancer metastasis through inflammatory reprogramming of the tumor microenvironment.

BACKGROUND: Early dissemination to distant organs accounts for the dismal prognosis of patients with pancreatic ductal adenocarcinoma (PDAC). Chronic, dysregulated, persistent and unresolved inflammation provides a preferred tumor microenvironment (TME) for tumorigenesis, development, and metastasis. A better understanding of the key regulators that maintain inflammatory TME and the development of predictive biomarkers to identify patients who are most likely to benefit from specific inflammatory-targeted therapies is crucial for advancing personalized cancer treatment. METHODS: This study identified cell-specific expression of CALB2 in human PDAC through single-cell RNA sequencing analysis and assessed its clinicopathological correlations in tissue microarray using multi-color immunofluorescence. Co-culture systems containing cancer-associated fibroblasts (CAFs) and patient-derived organoids (PDOs) in vitro and in vivo were employed to elucidate the effects of CALB2-activated CAFs on PDAC malignancy. Furthermore, CUT&RUN assays, luciferase reporter assays, RNA sequencing, and gain- or loss-of-function assays were used to unravel the molecular mechanisms of CALB2-mediated inflammatory reprogramming and metastasis. Additionally, immunocompetent KPC organoid allograft models were constructed to evaluate CALB2-induced immunosuppression and PDAC metastasis, as well as the efficacy of inflammation-targeted therapy. RESULTS: CALB2 was highly expressed both in CAFs and cancer cells and correlated with an unfavorable prognosis and immunosuppressive TME in PDAC patients. CALB2 collaborated with hypoxia to activate an inflammatory fibroblast phenotype, which promoted PDAC cell migration and PDO growth in vitro and in vivo. In turn, CALB2-activated CAFs upregulated CALB2 expression in cancer cells through IL6-STAT3 signaling-mediated direct transcription. In cancer cells, CALB2 further activated Ca2+-CXCL14 inflammatory axis to facilitate PDAC metastatic outgrowth and immunosuppression. Genetic or pharmaceutical inhibition of CXCL14 significantly suppressed CALB2-mediated metastatic colonization of PDAC cells in vivo and extended mouse survival. CONCLUSIONS: These findings identify CALB2 as a key regulator of inflammatory reprogramming to promote PDAC metastatic progression. Combination therapy with αCXCL14 monoclonal antibody and gemcitabine emerges as a promising strategy to suppress distant metastasis and improve survival outcomes in PDAC with CALB2 overexpression.

RNA methyltransferase NSUN2-mediated m5C methylation promotes Cr(VI)-induced malignant transformation and lung cancer by accelerating metabolism reprogramming.

Hexavalent chromium [Cr(VI)], one common environmental contaminant, has long been recognized as a carcinogen associated with lung cancer, but roles and mechanisms of Cr(VI)-induced epigenetic dysregulations in carcinogenesis remain to be investigated. In this study, we identified that RNA m5C methyltransferase NSUN2 was significantly upregulated in Cr(VI)-transformed cells and lung tissues of Cr(VI)-exposed mice. Inhibition of NSUN2 reduced cell proliferation, migration, colony formation and tube formation abilities. We found NSUN2-mediated m5C modification induced metabolic reprogramming and cell cycle by promoting the mRNA stabilities of ME1, GLUT3 and CDK2. In addition, knockdown of NSUN2 attenuated tumorigenesis and angiogenesis in vivo. RNA m5C reader ALYREF was identified to be involved in NSUN2-mediated m5C modification in Cr (VI)-induced carcinogenesis. Further study showed that EP300 induced NSUN2 upregulation through transcriptional activation by inducing histone modification at H3K27ac site for regulating Cr(VI) carcinogenesis. Our findings demonstrated novel role and mechanism of NSUN2 and epigenetic changes by increasing the RNA m5C modification that are important for Cr (VI)-induced carcinogenesis through NSUN2/ALYREF pathway. NSUN2, ALYREF, ME1, GLUT3 or/and CDK2 may be used as potential new biomarkers or/and therapeutic target(s) in the future.

Focused starvation of tumor cells using glucose oxidase: A comprehensive review.

Starvation therapy targets the high metabolic demand of tumor cells. It primarily leans over the consumption of intracellular glucose and simultaneous blockade of alternative metabolic pathways. The strategy involves the use of glucose oxidase (GOx) for catalyzing the conversion of glucose into gluconic acid and hydrogen peroxide. Under these conditions, metabolic re-programming of tumor cells enables the utilization of substrates such as amino acids, fatty acids and lipids. This can be overcome by co-administration of chemo-, photo- and immuno-therapeutics together with glucose oxidase. Targeted delivery of glucose oxidase at tumor site can be enabled with the use of nanoformulations. In this review, we highlight that the outcomes of starvation therapy can be improved using rationally developed nano-formulations. It is possible to load synergistically acting bioactives in these formulations and deliver in site-specific manner and hence achieve the elimination of tumors cells with greater efficacy.

Microbiota-derived acetate is associated with functionally optimal virus-specific CD8+ T cell responses to influenza virus infection via GPR43-dependent metabolic reprogramming.

The microbiota-associated factors that affect host susceptibility and adaptive immunity to influenza A virus (IAV) infection have not been fully elucidated. By comparing the microbiota composition between survivors and mice that succumbed to IAV strain PR8 infection, we identified that the commensal bacterium Blautia coccoides protects antibiotics (Abx)-treated or germ-free (GF) mice from PR8 infection by inducing functionally optimal virus-specific CD8+ T cell responses. Administration of exogenous acetate reproduced the protective effect of B. coccoides monocolonization in Abx and GF mice, enhancing oxidative phosphorylation and glycolysis as well as secretion of IFN-γ and granzyme B in virus-specific CD8+ T cells, dependent on GPR43 signaling and acetyl-CoA synthetase 2. Thus, we have demonstrated that microbiota-derived acetate possesses an antiviral effect that induces an optimal virus-specific CD8+ T cell response to IAV PR8 infection via GPR43-dependent metabolic reprogramming.

Rewriting cellular fate: epigenetic interventions in obesity and cellular programming.

External constraints, such as development, disease, and environment, can induce changes in epigenomic patterns that may profoundly impact the health trajectory of fetuses and neonates into adulthood, influencing conditions like obesity. Epigenetic modifications encompass processes including DNA methylation, covalent histone modifications, and RNA-mediated regulation. Beyond forward cellular differentiation (cell programming), terminally differentiated cells are reverted to a pluripotent or even totipotent state, that is, cellular reprogramming. Epigenetic modulators facilitate or erase histone and DNA modifications both in vivo and in vitro during programming and reprogramming. Noticeably, obesity is a complex metabolic disorder driven by both genetic and environmental factors. Increasing evidence suggests that epigenetic modifications play a critical role in the regulation of gene expression involved in adipogenesis, energy homeostasis, and metabolic pathways. Hence, we discuss the mechanisms by which epigenetic interventions influence obesity, focusing on DNA methylation, histone modifications, and non-coding RNAs. We also analyze the methodologies that have been pivotal in uncovering these epigenetic regulations, i.e., Large-scale screening has been instrumental in identifying genes and pathways susceptible to epigenetic control, particularly in the context of adipogenesis and metabolic homeostasis; Single-cell RNA sequencing (scRNA-seq) provides a high-resolution view of gene expression patterns at the individual cell level, revealing the heterogeneity and dynamics of epigenetic regulation during cellular differentiation and reprogramming; Chromatin immunoprecipitation (ChIP) assays, focused on candidate genes, have been crucial for characterizing histone modifications and transcription factor binding at specific genomic loci, thereby elucidating the epigenetic mechanisms that govern cellular programming; Somatic cell nuclear transfer (SCNT) and cell fusion techniques have been employed to study the epigenetic reprogramming accompanying cloning and the generation of hybrid cells with pluripotent characteristics, etc. These approaches have been instrumental in identifying specific epigenetic marks and pathways implicated in obesity, providing a foundation for developing targeted therapeutic interventions. Understanding the dynamic interplay between epigenetic regulation and cellular programming is crucial for advancing mechanism and clinical management of obesity.

Targeting mutant p53: a key player in breast cancer pathogenesis and beyond.

The p53 mutation is the most common genetic mutation associated with human neoplasia. TP53 missense mutations, which frequently arise early in breast cancer, are present in over thirty percent of breast tumors. In breast cancer, p53 mutations are linked to a more aggressive course of the disease and worse overall survival rates. TP53 mutations are mostly seen in triple-negative breast cancer, a very diverse kind of the disease. The majority of TP53 mutations originate in the replacement of individual amino acids within the p53 protein's core domain, giving rise to a variety of variations referred to as "mutant p53s." In addition to gaining carcinogenic qualities through gain-of-function pathways, these mutants lose the typical tumor-suppressive features of p53 to variable degrees. The gain-of-function impact of stabilized mutant p53 causes tumor-specific dependency and resistance to therapy. P53 is a prospective target for cancer therapy because of its tumor-suppressive qualities and the numerous alterations that it experiences in tumors. Phenotypic abnormalities in breast cancer, notably poorly differentiated basal-like tumors are frequently linked to high-grade tumors. By comparing data from cell and animal models with clinical outcomes in breast cancer, this study investigates the molecular mechanisms that convert gene alterations into the pathogenic consequences of mutant p53's tumorigenic activity. The study delves into current and novel treatment approaches aimed at targeting p53 mutations, taking into account the similarities and differences in p53 regulatory mechanisms between mutant and wild-type forms, as well.

Hippocampal rejuvenation by a single intracerebral injection of one-carbon metabolites in C57BL6 old wild-type mice.

The Izpisua-Belmonte group identified a cocktail of metabolites that promote partial reprogramming in cultured muscle cells. We tested the effect of brain injection of these metabolites in the dentate gyrus of aged wild-type mice. The dentate gyrus is a brain region essential for memory function and is extremely vulnerable to aging. A single injection of the cocktail containing four compounds (putrescine, glycine, methionine and threonine) partially reversed brain aging phenotypes and epigenetic alterations in age-associated genes. Our analysis revealed three levels: chromatin methylation, RNA sequencing, and protein expression. Functional studies complemented the previous ones, showing cognitive improvement. In summary, we report the reversal of various age-associated epigenetic changes, such as the transcription factor Zic4, and several changes related to cellular rejuvenation in the dentate gyrus (DG). These changes include increased expression of the Sox2 protein. Finally, the increases in the survival of newly generated neurons and the levels of the NMDA receptor subunit GluN2B were accompanied by improvements in both short-term and long-term memory performance. Based on these results, we propose the use of these metabolites to explore new strategies for the development of potential treatments for age-related brain diseases.

Envisioning Glucose Transporters (GLUTs and SGLTs) as Novel Intervention against Cancer: Drug Discovery Perspective and Targeting Approach.

Metabolic reprogramming and altered cellular energetics have been recently established as an important cancer hallmark. The modulation of glucose metabolism is one of the important characteristic features of metabolic reprogramming in cancer. It contributes to oncogenic progression by supporting the increased biosynthetic and bio-energetic demands of tumor cells. This oncogenic transformation consequently results in elevated expression of glucose transporters in these cells. Moreover, various cancers exhibit abnormal transporter expression patterns compared to normal tissues. Recent investigations have underlined the significance of glucose transporters in regulating cancer cell survival, proliferation, and metastasis. Abnormal regulation of these transporters, which exhibit varying affinities for hexoses, could enable cancer cells to efficiently manage their energy supply, offering a crucial edge for proliferation. Exploiting the upregulated expression of glucose transporters, GLUTs, and Sodium Linked Glucose Transporters (SGLTs), could serve as a novel therapeutic intervention for anti-cancer drug discovery as well as provide a unique targeting approach for drug delivery to specific tumor tissues. This review aims to discussthe previous and emerging research on the expression of various types of glucose transporters in tumor tissues, the role of glucose transport inhibitors as a cancer therapy intervention as well as emerging GLUT/SGLT-mediated drug delivery strategies that can be therapeutically employed to target various cancers.

CASPER: A Phase I trial combining calaspargase pegol-mnkl and cobimetinib in pancreatic cancer.

Asparagine synthetase (ASNS) catalyzes the biosynthesis of asparagine from aspartate and glutamine. Cells lacking ASNS, however, are auxotrophic for asparagine. Use of L-asparaginase to promote asparagine starvation in solid tumors with low ASNS levels, such as pancreatic ductal adenocarcinoma (PDAC), is a rationale treatment strategy. However, tumor cell resistance to L-asparaginase has limited its clinical utility. Our preclinical studies show that RAS/MAPK signaling circumvents L-asparaginase-induced tumor killing, but L-asparaginase and MEK inhibition potentiated tumor killing; suggesting that this combination may provide meaningful clinical benefit to patients with PDAC. This Phase I trial (NCT05034627) will evaluate the safety and tolerability of the MEK inhibitor, cobimetinib, in combination with pegylated L-asparaginase, L calaspargase pegol-mknl, in patients with locally-advanced or metastatic PDAC.

[Box: see text].

Glycerophospholipid-driven lipid metabolic reprogramming as a common key mechanism in the progression of human primary hepatocellular carcinoma and cholangiocarcinoma.

Metabolic reprogramming, a key mechanism regulating the growth and recurrence of hepatocellular carcinoma (HCC) and cholangiocarcinoma (CCA), still lacks effective clinical strategies for its integration into the precise screening of primary liver cancer. This study utilized ultra-high-performance liquid chromatography with quadrupole time-of-flight mass spectrometry to conduct a comprehensive, non-targeted metabolomics analysis, revealing significant upregulation of lipid metabolites such as phosphatidylcholine and lysophosphatidylcholine in patients with HCC and CCA, particularly within the glycerophospholipid metabolic pathway. Hematoxylin and eosin and immunohistochemical staining demonstrated marked upregulation of phospholipase A2 in tumor tissues, further emphasizing the potential of lipid metabolism as a therapeutic target and its important part in the course of cancer. This work provides a new viewpoint for addressing the clinical challenges associated with HCC and CCA, laying the groundwork for the broad application of early diagnosis and personalized treatment strategies, and ultimately aiming to provide tailored and precise therapeutic options for patients.

ETV4­mediated transcriptional activation of SLC12A5 exacerbates ferroptosis resistance and glucose metabolism reprogramming in breast cancer cells.

Solute carrier family 12 member 5 (SLC12A5) is an oncogene in numerous types of cancer, however its function in breast cancer (BC) remains elusive. ETS translocation variant 4 (ETV4) promotes BC. Therefore, the present study aimed to elucidate the role of SLC12A5 in ferroptosis and glucose metabolism in BC cells as well as to understand the underlying mechanism. Analysis of data from the UALCAN database demonstrated expression levels of SLC12A5 in BC and its association with prognosis. Reverse transcription­quantitative PCR and western blotting were conducted to evaluate the expression levels of SLC12A5 and ETV4 in BC cells. The abilities of BC cells to proliferate, migrate and invade were assessed using Cell Counting Kit­8, colony formation, wound healing and Transwell assays. Thiobarbituric acid reactive substances assay and a C11 BODIPY 581/591 probe were used to evaluate lipid peroxidation. Ferroptosis resistance was evaluated by the measurement of Fe2+ and ferroptosis­related solute carrier family 7a member 11 (SLC7A11), glutathione peroxidase 4 (GPX4), acyl­CoA synthetase long­chain family member 4 (ACSL4) and transferrin receptor 1 (TFR1) protein levels. Glycolysis was assessed via evaluation of extracellular acidification rate, oxygen consumption rate, lactate production and glucose consumption. Finally, luciferase reporter and chromatin immunoprecipitation assay were used to verify the interaction between ETV4 and the SLC12A5 promoter. UALCAN database analysis indicated that SLC12A5 was upregulated in BC tissues and cells and that SLC12A5 elevation indicated a poor prognosis of patients with BC. SLC12A5 knockdown suppressed the BC cell proliferative, migratory and invasive capabilities. Moreover, SLC12A5 knockdown decreased BC cell ferroptosis resistance and glucose metabolism reprogramming. The transcription factor ETV4 was demonstrated to bind to the SLC12A5 promoter and upregulate its transcription. Furthermore, ETV4 overexpression counteracted the suppressive effect of SLC12A5 knockdown on the BC cell proliferative, migratory and invasive abilities, as well as on ferroptosis resistance and glucose metabolism reprogramming. Transcriptional activation of SLC12A5 by ETV4 modulated the migration, invasion, ferroptosis resistance and glucose metabolism reprogramming of BC cells.

Sodium selenite inhibits cervical cancer progression via ROS-mediated suppression of glucose metabolic reprogramming.

AIMS: This study aims to explore the inhibitory effect of selenium on cervical cancer through suppression of glucose metabolic reprogramming and its underlying mechanisms. METHODS: Sodium selenite (SS) treated HeLa and SiHa cells were assessed for proliferation using the CCK-8 assay and immunofluorescence. DNA synthesis was measured with the EdU assay. A nude mouse xenograft model evaluated SS's anti-cervical cancer effects. Reactive oxygen species (ROS) and mitochondrial membrane potential were measured using flow cytometry, DCFH-DA, and JC-1 probes, respectively. Apoptosis was detected via Annexin V/PI staining and Western blot. Glucose uptake, lactate production, and ATP generation were determined using 2-NBDG probes and assay kits. The mRNA and protein levels of glycolysis-related genes HK2, GLUT1, and PDK1 were measured using RT-qPCR and Western blot. KEY FINDINGS: SS inhibited HeLa and SiHa cells viability in a dose- and time-dependent manner. Intraperitoneal injection of SS in nude mice significantly inhibited HeLa cell xenograft growth without evident hepatotoxicity or nephrotoxicity. SS inhibited glucose metabolic reprogramming in cancer cells primarily via ROS-mediated AKT/mTOR/HIF-1α pathway inhibition. Pretreatment with N-acetylcysteine (NAC) or MHY1485 (an mTOR activator) partially reversed the inhibitory effects of SS on glucose metabolic reprogramming, cell proliferation, and migration, as well as its pro-apoptotic effects. SIGNIFICANCE: SS exhibited anti-cervical cancer effects, likely through the induction of ROS generation and inhibition of glucose metabolic reprogramming in cervical cancer cells, thereby inhibiting cell proliferation and promoting apoptosis. These findings provide new insights into understanding the molecular mechanisms underlying SS for potential new drug development for cervical cancer.

Alternative Method for Obtaining Human-Induced Pluripotent Stem Cell Lines and Three-Dimensional Growth: A Simplified, Passage-Free Approach that Minimizes Labor.

Induced pluripotent stem cells (iPSCs) hold significant promise for numerous applications in regenerative medicine, disease modeling, and drug discovery. However, the conventional workflow for iPSC generation, with cells grown under two-dimensional conditions, presents several challenges, including the need for specialized scientific skills such as morphologically assessing and picking colonies and removing differentiated cells during the establishment phase. Furthermore, maintaining established iPSCs in three-dimensional culture systems, while offering scalability, necessitates an enzymatic dissociation step for their further growth in a complex and time-consuming protocol. In this study, we introduce a novel approach to address these challenges by reprogramming somatic cells grown under three-dimensional conditions as spheres using a bioreactor, thereby eliminating the need for two-dimensional culture and colony picking. The iPSCs generated in this study were maintained under three-dimensional conditions simply by transferring spheres to the next bioreactor, without the need for an enzymatic dissociation step. This streamlined method simplifies the workflow, reduces technical variability and labor, and paves the way for future advancements in iPSC research and its wider applications. Key features • Establishment of induced pluripotent stem cells in a three-dimensional environment. • Maintenance and cryopreservation of iPSCs without the need for a dissociation step.

Meiosis as a mechanism for epigenetic reprogramming and cellular rejuvenation.

Meiosis is a hallmark of sexual reproduction because it represents the transition from one life cycle to the next and, in animals, meiosis produces gametes. Why meiosis evolved has been debated and most studies have focused on recombination of the parental alleles as the main function of meiosis. However, 40 years ago, Robin Holliday proposed that an essential function of meiosis is to oppose the consequence of successive mitoses that cause cellular aging. Cellular aging results from accumulated defective organelles and proteins and modifications of chromatin in the form of DNA methylation and histone modifications referred to collectively as epigenetic marks. Here, recent findings supporting the hypothesis that meiosis opposes cellular aging are reviewed and placed in the context of the diversity of the life cycles of eukaryotes, including animals, yeast, flowering plants and the bryophyte Marchantia.

Mechanisms of neural infiltration-mediated tumor metabolic reprogramming impacting immunotherapy efficacy in non-small cell lung cancer.

BACKGROUND: Current evidence underlines the active role of neural infiltration and axonogenesis within the tumor microenvironment (TME), with implications for tumor progression. Infiltrating nerves stimulate tumor growth and dissemination by secreting neurotransmitters, whereas tumor cells influence nerve growth and differentiation through complex interactions, promoting tumor progression. However, the role of neural infiltration in the progression of non-small cell lung cancer (NSCLC) remains unclear. METHODS: This study employs the techniques of immunohistochemistry, immunofluorescence, RNA sequencing, molecular biology experiments, and a murine orthotopic lung cancer model to deeply analyze the specific mechanisms behind the differential efficacy of NSCLC immunotherapy from the perspectives of neuro-tumor signal transduction, tumor metabolism, and tumor immunity. RESULTS: This study demonstrates that nerve growth factor (NGF) drives neural infiltration in NSCLC, and 5-hydroxytryptamine (5-HT), which is secreted by nerves, is significantly elevated in tumors with extensive neural infiltration. Transcriptome sequencing revealed that 5-HT enhanced glycolysis in NSCLC cells. Pathway analysis indicated that 5-HT activated the PI3K/Akt/mTOR pathway, promoting tumor metabolic reprogramming. This reprogramming exacerbated immunosuppression in the TME. Neutralizing 5-HT-mediated metabolic reprogramming in tumor immunity enhanced the efficacy of PD-1 monoclonal antibody treatment in mice. CONCLUSIONS: The findings of this study provide a novel perspective on the crosstalk between nerves and lung cancer cells and provide insights into further investigations into the role of nerve infiltration in NSCLC progression.

Modeling respiratory tract diseases for clinical translation employing conditionally reprogrammed cells.

Preclinical models serve as indispensable tools in translational medicine. Specifically, patient-derived models such as patient-derived xenografts (PDX), induced pluripotent stem cells (iPSC), organoids, and recently developed technique of conditional reprogramming (CR) have been employed to reflect the host characteristics of diseases. CR technology involves co-culturing epithelial cells with irradiated Swiss-3T3-J2 mouse fibroblasts (feeder cells) in the presence of a Rho kinase (ROCK) inhibitor, Y-27632. CR technique facilitates the rapid conversion of both normal and malignant cells into a "reprogrammed stem-like" state, marked by robust in vitro proliferation. This is achieved without reliance on exogenous gene expression or viral transfection, while maintaining the genetic profile of the parental cells. So far, CR technology has been used to study biology of diseases, targeted therapies (precision medicine), regenerative medicine, and noninvasive diagnosis and surveillance. Respiratory diseases, ranking as the third leading cause of global mortality, pose a significant burden to healthcare systems worldwide. Given the substantial mortality and morbidity rates of respiratory diseases, efficient and rapid preclinical models are imperative to accurately recapitulate the diverse spectrum of respiratory conditions. In this article, we discuss the applications and future potential of CR technology in modeling various respiratory tract diseases, including lung cancer, respiratory viral infections (such as influenza and Covid-19 and etc.), asthma, cystic fibrosis, respiratory papillomatosis, and upper aerodigestive track tumors. Furthermore, we discuss the potential utility of CR in personalized medicine, regenerative medicine, and clinical translation.