No information is available on the use of fludarabine during breastfeeding. Because of potential toxicity to the infant, the manufacturer recommends withholding breastfeeding during therapy and for one week after the last dose.

Long non-coding RNAs (lncRNAs) have emerged as key regulators of cancer progression through their interaction with microRNAs and modulation of gene expression. However, their role in mitochondrial metabolism, particularly in non-small cell lung cancer (NSCLC), remains poorly defined. In this study, we found that LINC02802 was significantly upregulated in NSCLC tissues and associated with poor prognosis. Mechanistically, LINC02802 acts as a competing endogenous RNA (ceRNA) for miR-1976, thereby relieving the suppression of solute carrier family 25 member 51(SLC25A51). Elevated SLC25A51 enhances mitochondrial NAD[+] import, leading to an increased NAD[+]/NADH ratio and promoting oxidative TCA cycle flux. Functionally, this shift supports tumor cell proliferation and migration. Rescue experiments confirmed that the oncogenic effect of LINC02802 is dependent on the miR-1976/SLC25A51 axis. Interestingly, either silencing LINC02802 with antisense oligonucleotides (ASOs) or treating cells with fludarabine phosphate, an SLC25A51 inhibitor, successfully reversed cisplatin resistance in lung cancer cells. Our findings reveal a novel lncRNA-microRNA-metabolic axis wherein LINC02802 facilitates NSCLC progression by reprogramming mitochondrial metabolism via miR-1976-mediated upregulation of SLC25A51. Targeting this axis may offer therapeutic potential for metabolic intervention in NSCLC.

Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide. Accumulating evidence suggests that epigenetic dysregulation contributes to the initiation and progression of HCC. We aimed to investigate key epigenetic regulators that contribute to tumorigenesis and progression, providing a theoretical basis for targeted therapy for HCC. We performed a comprehensive epigenetic analysis of differentially expressed genes in LIHC from the TCGA database. We identified fibrillarin (FBL), an rRNA 2'-O-methyltransferase, as an essential contributor to HCC. A series of in vitro and in vivo biological experiments were performed to investigate the potential mechanisms of FBL. FBL knockdown suppressed the proliferation of HCC cells. In vivo studies using cell-derived xenograft (CDX), patient-derived xenograft (PDX), and diethylnitrosamine (DEN)-induced HCC models in Fbl liver-specific knockout mice demonstrated the critical role of FBL in HCC carcinogenesis and progression. Mechanistically, FBL regulates the expression of CAD in HCC cells by recruiting YY1 to the CAD promoter region. We also revealed that fludarabine phosphate is a novel inhibitor of FBL and can inhibit HCC growth in vitro and in vivo. The antitumor activity of lenvatinib has been shown to be synergistically enhanced by fludarabine phosphate. Our study highlights the cancer-promoting role of the FBL-YY1-CAD axis in HCC and identifies fludarabine phosphate as a novel inhibitor of FBL. A schematic diagram depicting the FBL-YY1-CAD signaling pathway and its regulatory role in HCC progression.

Most cancer patients diagnosed with late-stage head and neck squamous cell carcinoma are treated with chemoradiotherapy, which can lead to toxicity. One potential alternative is tumor-limited conversion of a prodrug into its cytotoxic form. We reason this could be achieved by transient and tumor-specific expression of purine nucleoside phosphorylase (PNP), an Escherichia coli enzyme that converts fludarabine into 2-fluoroadenine, a potent cytotoxic drug. To efficiently express bacterial PNP in tumors, we evaluate 44 chemically distinct lipid nanoparticles (LNPs) using species-agnostic DNA barcoding in tumor-bearing mice. Our lead LNP, designated LNP intratumoral (LNP[IT]), delivers mRNA that leads to PNP expression in vivo. Additionally, in tumor cells transfected with LNP[IT], we observe upregulated pathways related to RNA and protein metabolism, providing insight into the tumor cell response to LNPs in vivo. When mice are treated with LNP[IT]-PNP, then subsequently given fludarabine phosphate, we observe anti-tumor responses. These data are consistent with an approach in which LNP-mRNA expression of a bacterial enzyme activates a prodrug in solid tumors.

Resiquimod (R-848), a synthetic TLR7 agonist, modulates immune responses, primarily inducing Th1-biased immunity in mammals. In contrast, our previous studies revealed that R-848 stimulates both Th1 and Th2 responses in chickens. The current research investigates the molecular mechanisms underlying these immune responses in chickens. Pooled splenocytes harvested from chickens (n = 2/group) at 24 h post R-848 treatment were subjected to RNA sequencing and significant differentially expressed genes (DEGs) were identified compared to controls. Eight key genes associated with signal transduction (MAPK14, MAP3K8, PIK3CD, STAT1, STAT3, MAPK11, LRRK2, and GATA3) were validated via real-time PCR in chicken peripheral blood mononuclear cells (PBMCs) from six biological replicates. Pharmacological inhibitors or chloroquine were employed to elucidate the signalling pathways. SB202190, IC-87114, and fludarabine phosphate suppressed the R-848-induced expression of MAPK14, PIK3CD, and STAT1, respectively, while chloroquine decreased STAT3 expression. Intriguingly, chloroquine treatment enhanced the R-848-mediated expression of MAPK11, LRRK2, and GATA3. These results align with transcriptomic findings and highlight the upregulation of STAT1 and STAT3 as potential contributors to the induction of Th1 and Th2 immune responses by R-848 in chickens. These insights provide a foundation for optimizing R-848 as an immunomodulatory agent in avian species.

Monitoring the concentration of Fludarabine phosphate, a standard chemotherapeutic drug widely used in cancer treatment, is vital for ensuring the drug's safety and effectiveness, tailoring treatments to individual needs, and consequently improving overall patient outcomes. Regarding the limitations of conventional techniques in terms of complexity, large time measurements, and a high cost, there is an urgent need to develop simple, rapid, and cost-effective devices. In this paper, we report the design of an aptasensor for the specific and selective detection of Fludarabine. Systematic evolution of ligands by exponential enrichment (SELEX) protocol was performed to select a specific aptamer for Fludarabine. Eleven rounds were carried out, and nine sequences were selected. Based on the dissociation constant (Kd), Ful-3, exhibiting the highest affinity (18.86 nM), was chosen and integrated into a simple electrochemical aptasensing platform for Fludarabine detection. Electrochemical results demonstrated good performance of the selected aptamer in detecting Fludarabine within the analytical range of 1 to 150 pg/mL and with LOD and LOQ in the order of 0.11 pg/mL (0.31 fM) and 0.39 pg/mL (1.06 fM), respectively. The developed platform also showed good selectivity against different analogous molecules and high applicability in serum-spiked samples, with recovery percentages ranging from 96.81 to 99.04%. Considering the encouraging results, this research presents an excellent alternative in terms of simplicity, stability, ease of use, reduction of sample volume, and low cost.

In the field of natural product research, the rediscovery of already-known compounds is one of the significant issues hindering new drug development. Recently, an innovative approach called bioactivity-HiTES has been developed to overcome this limitation, and several new bioactive metabolites have been successfully characterized by this method. In this study, we applied bioactivity-HiTES to Corynebacterium matruchotii, the human oral bacterium, with 3120 clinical drugs as potential elicitors. As a result, we identified two cryptic metabolites, methylindole-3-acetate (MIAA) and indole-3-acetic acid (IAA), elicited by imidafenacin, a urinary antispasmodic drug approved by the Japanese Pharmaceuticals and Medical Devices Agency (PMDA). MIAA showed weak antibacterial activity against a pulmonary disease-causing Mycobacterium conceptionense with an IC50 value of 185.7 μM. Unexpectedly, we also found that C. matruchotii metabolized fludarabine phosphate, a USFDA-approved anticancer drug, to 2-fluoroadenine which displayed moderate antibacterial activity against both Bacillus subtilis and Escherichia coli, with IC50 values of 8.9 and 20.1 μM, respectively. Finally, acelarin, a prodrug of the anticancer drug gemcitabine, was found to exhibit unreported antibacterial activity against B. subtilis with an IC50 value of 33.6 μM through the bioactivity-HiTES method as well. These results indicate that bioactivity-HiTES can also be applied to discover biotransformed products in addition to finding cryptic metabolites in microbes.

ITC/Toc@Gd2(FLP)3 core@shell nanocarriers with a chemotherapeutic cocktail of lipophilic irinotecan (ITC) as the particle core and hydrophilic fludarabine phosphate (FLP) in the particle shell are realized. They are prepared via a microemulsion approach with ITC dissolved in tocopherol (Toc) as droplet phase and stabilized by water-insoluble Gd2(FLP)3. The synthesis can be followed by zeta-potential analysis. X-ray powder diffraction, infrared spectroscopy, elemental analysis, thermogravimetry, and photometry show a drug load of 49 μg per mL ITC and 317 μg per mL FLP at a nanocarrier concentration of 1.5 mg mL-1. Size and structure are evidenced by electron microscopy, resulting in a total diameter of 45 ± 16 nm, an inner core of 40 ± 17 nm, and a shell of 3-8 nm. In vitro studies with different cancer cell lines (i.e., human melanoma/SK-Mel-28, cervical cancer/HeLa, mouse pancreatic cancer/Panc02 and KPC as well as human pancreatic cancer/Capan-1 cells) prove efficient nanocarrier uptake and promising cytostatic efficacy. Specifically for KPC cells, ITC/Toc@Gd2(FLP)3 nanocarriers show an increased efficacy, with half maximal inhibitory concentration (IC50: 4.2 μM) > 10 times lower than the free drugs (IC50: ITC: 47.7 μM, FLP: 143 μM). This points to the synergistic effect of the ITC/FLP drug cocktail in the nanocarriers and may result in a promising strategy to treat pancreatic ductal adenocarcinoma (PDAC).

Immune response plays a crucial role in post-myocardial infarction (MI) myocardial remodeling. Neogenin (Neo1), a multifunctional transmembrane receptor, plays a critical role in the immune response; however, whether Neo1 participates in pathological myocardial remodeling after MI is unclear. Our study found that Neo1 expression changed significantly after MI in vivo and after LPS + IFN-γ stimulation in bone marrow-derived macrophages (BMDMs) in vitro. Neo1 functional deficiency (using a neutralizing antibody) and macrophage-specific Neo1 deficiency (induced by Neo1flox/flox;Cx3cr1cre mice) increased infarction size, enhanced cardiac fibrosis and cardiomyocyte apoptosis, and exacerbated left ventricular dysfunction post-MI in mice. Mechanistically, Neo1 deficiency promoted macrophage infiltration into the ischemic myocardium and transformation to a proinflammatory phenotype, subsequently exacerbating the inflammatory response and impairing inflammation resolution post-MI. Neo1 deficiency regulated macrophage phenotype and function, possibly through the JAK1-STAT1 pathway, as confirmed in BMDMs in vitro. Blocking the JAK1-STAT1 pathway with fludarabine phosphate abolished the impact of Neo1 on macrophage phenotype and function, inflammatory response, inflammation resolution, cardiomyocyte apoptosis, cardiac fibrosis, infarction size and cardiac function. In conclusion, Neo1 deficiency aggravates inflammation and left ventricular remodeling post-MI by modulating macrophage phenotypes and functions via the JAK1-STAT1 signaling pathway. These findings highlight the anti-inflammatory potential of Neo1, offering new perspectives for therapeutic targets in MI treatment. Neo1 deficiency aggravated inflammation and left ventricular remodeling after MI by modulating macrophage phenotypes and functions via the JAK1-STAT1 signaling pathway.

Solute carrier family 25 member 51 (SLC25A51) was recently identified as the mammalian mitochondrial NAD+ transporter essential for mitochondria functions. However, the role of SLC25A51 in human disease, such as cancer, remains undefined. Here, we report that SLC25A51 is upregulated in multiple cancers, which promotes cancer cells proliferation. Loss of SLC25A51 elevates the mitochondrial proteins acetylation levels due to SIRT3 dysfunctions, leading to the impairment of P5CS enzymatic activity, which is the key enzyme in proline biogenesis, and the reduction in proline contents. Notably, we find fludarabine phosphate, an FDA-approved drug, is able to bind with and inhibit SLC25A51 functions, causing mitochondrial NAD+ decrease and proteins hyperacetylation, which could further synergize with aspirin to reinforce the anti-tumor efficacy. Our study reveals that SLC25A51 is an attractive anti-cancer target, and provides a novel drug combination of fludarabine phosphate with aspirin as a potential cancer therapy strategy.

Interferon-tau (IFNT), a pregnancy recognition signal in ruminants, promotes the establishment of endometrial receptivity by inducing the expression of interferon-stimulated genes (ISGs) via the Janus kinase/signal transducer and activator of transcription (JAK/STATs) signaling pathway. However, the precise mechanisms remain largely unknown. Ubiquitin-specific protease 18 (USP18) acts specifically on the ISGylation modification system to exert deubiquitination and participates in the regulation of the type I IFN signaling pathway. The purpose of this study was to determine the role and mechanism of USP18 on endometrial receptivity in goat. USP18 was mainly localized in the uterine luminal and glandular epithelium, and its expression levels were significantly increased from days 5-18 of early pregnancy. Progesterone (P4), estradiol (E2), and IFNT significantly stimulated USP18 expression in goat endometrial epithelial cells (gEECs) cultured in vitro. Meanwhile, the markers of endometrial receptivity HOXA11, ITGB1, ITGB3, and ITGB5 were significantly upregulated after USP18 overexpression in gEECs. However, USP18 interference significantly inhibited the expression of HOXA10, ITGB1, ITGB3, and ITGB5 in gEECs. In addition, both the phosphorylation levels of STAT1 and the expression of ISGylation-modified proteins were significantly increased after USP18 silencing in gEECs. Furthermore, pretreatment with the STAT1 inhibitor Fludara markedly restored the effect of USP18 interference in gEECs. In summary, USP18 may play an important role in promoting goat endometrial receptivity by regulating the JAK/STAT1 pathway and ISGylation.