m6A-driven NAT10 translation facilitates fatty acid metabolic rewiring to suppress ferroptosis and promote ovarian tumorigenesis through enhancing ACOT7 mRNA acetylation.

RNA epigenetic modifications have been implicated in cancer progression. However, the interplay between distinct RNA modifications and its role in cancer metabolism remain largely unexplored. Our study demonstrates that N-acetyltransferase 10 (NAT10) is notably upregulated in ovarian cancer (OC), correlating with poor patient prognosis. IGF2BP1 enhances the translation of NAT10 mRNA in an m6A-dependent manner in OC cells. NAT10 drives tumorigenesis by mediating N4-acetylcytidine (ac4C) modification of ACOT7 mRNA, thereby augmenting its stability and translation. This NAT10-ACOT7 axis modulates fatty acid metabolism in cancer cells and promotes tumor progression by suppressing ferroptosis. Additionally, our research identifies fludarabine as a small molecule inhibitor targeting NAT10, inhibits the ac4C modification and expression of ACOT7 mRNA. By using cell derived xenograft model and patient derived organoid model, we show that fludarabine effectively suppresses ovarian tumorigenesis. Overall, our study highlights the pivotal role of the NAT10-ACOT7 axis in the malignant cancer progression, underscoring the potential of targeting NAT10-mediated ac4C modification as a viable therapeutic strategy for this disease.

LncRNAPVT1 is Associated with Cancer-Associated Fibroblasts Proliferation Through Regulating TGF-ßin Oral Squamous Cell Carcinoma.

INTRODUCTION: Human oral squamous cell carcinoma (OSCC) is the most common type of oral cancer and has a poor survival rate. Cell-cell communication between OSCC cells and cancer-associated fibroblasts (CAFs) plays important roles in OSCC progression. We previously demonstrated that CAFs promote OSCC cell migration and invasion. However, how OSCC cells influence CAFs proliferation is unknown. METHODS: Knockdown of PVT1 was confirmed using lentivirus infection technique. CAFs in tissues were identified by staining the cells with α-SMA using immunohistochemical technique. CCK-8 assay was used to evaluate cell proliferation. The mRNA level of a gene was measured by qRT-PCR. Secreted TGF-ß were detected using ELISA assay. RESULTS: We found that knockdown of the long non-coding RNA (lncRNA) plasmacytoma variant translocation 1 (PVT1) was associated with a low density of CAFs in xenograft tumors in mice; further analysis revealed that PVT1 in OSCC cells induced CAF proliferation through transforming growth factor (TGF)-ß. DISCUSSION: Our results demonstrate that lncRNA PVT1 in tumor cells participates in CAF development in OSCC by regulating TGF-ß. This study revealed a new mechanism by which PVT1 regulates OSCC progression and PVT1 is a potential therapeutic target in OSCC.

CSTF3 contributes to platinum resistance in ovarian cancer through alternative polyadenylation of lncRNA NEAT1 and generating the short isoform NEAT1_1.

Platinum-based chemotherapy is the standard postoperative adjuvant treatment for ovarian cancer (OC). Despite the initial response to chemotherapy, 85% of advanced OC patients will have recurrent disease. Relapsed disease and platinum resistance are the major causes of death in OC patients. In this study, we compared the global regulation of alternative polyadenylation (APA) in platinum-resistant and platinum-sensitive tissues of OC patients by analyzing a set of single-cell RNA sequencing (scRNA-seq) data from public databases and found that platinum-resistant patients exhibited global 3' untranslated region (UTR) shortening due to the different usage of polyadenylation sites (PASs). The APA regulator CSTF3 was the most significantly upregulated gene in epithelial cells of platinum-resistant OC. CSTF3 knockdown increased the sensitivity of OC cells to platinum. The lncRNA NEAT1 has two isoforms, short (NEAT1_1) and long (NEAT1_2) transcript, because of the APA processing in 3'UTR. We found that CSTF3 knockdown reduced the usage of NEAT1 proximal PAS to lengthen the transcript and facilitate the expression of NEAT1_2. Downregulation of the expression of NEAT1 (NEAT1_1/_2), but not only NEAT1_2, also increased the sensitivity of OC cells to platinum. Overexpressed NEAT1_1 reversed the platinum resistance of OC cells after knocking down CSTF3 expression. Furthermore, downregulated expression of CSTF3 and NEAT1_1, rather than NEAT1_2, was positively correlated with inactivation of the PI3K/AKT/mTOR pathway in OC cells. Together, our findings revealed a novel mechanism of APA regulation in platinum-resistant OC. CSTF3 directly bound downstream of the NEAT1 proximal PAS to generate the short isoform NEAT1_1 and was conducive to platinum resistance, which provides a potential biomarker and therapeutic strategy for platinum-resistant OC patients.

A potent Henipavirus cross-neutralizing antibody reveals a dynamic fusion-triggering pattern of the G-tetramer.

The Hendra and Nipah viruses (HNVs) are highly pathogenic pathogens without approved interventions for human use. In addition, the interaction pattern between the attachment (G) and fusion (F) glycoproteins required for virus entry remains unclear. Here, we isolate a panel of Macaca-derived G-specific antibodies that cross-neutralize HNVs via multiple mechanisms. The most potent antibody, 1E5, confers adequate protection against the Nipah virus challenge in female hamsters. Crystallography demonstrates that 1E5 has a highly similar binding pattern to the receptor. In cryo-electron microscopy studies, the tendency of 1E5 to bind to the upper or lower heads results in two distinct quaternary structures of G. Furthermore, we identify the extended outer loop ß1S2-ß1S3 of G and two pockets on the apical region of fusion (F) glycoprotein as the essential sites for G-F interactions. This work highlights promising drug candidates against HNVs and contributes deeper insights into the viruses.

Role of prognostic gene DKK1 in oral squamous cell carcinoma.

Oral squamous cell carcinoma (OSCC) is one of the most common squamous cell carcinomas of the head and neck. The morbidity and mortality rates of OSCC have increased in recent years. However, the pathogenesis of this disease remains unknown. The present study aimed to identify predictive biomarkers and therapeutic targets for OSCC. Bioinformatics screening of differentially expressed genes in OSCC was performed based on data from The Cancer Genome Atlas and Gene Expression Omnibus databases. Dickkopf Wnt signaling pathway inhibitor 1 (DKK1) was identified to be associated with survival, tumor immunity and DNA repair in OSCC. Furthermore, the effects of DKK1 were evaluated by the knockdown of DKK1 in two OSCC cell lines. The proliferation, clonogenicity, migration and invasion of the cells were assessed in vitro using Cell Counting Kit-8, colony formation, wound healing and Transwell assays, respectively, and were found to be inhibited by DKK1 knockdown. The present study suggests that DKK1 may be used in the prognosis of patients with OSCC and that targeting DKK1 is a potential strategy for OSCC therapy.

Site-specific controlled-release nanoparticles for immune reprogramming via dual metabolic inhibition against triple-negative breast cancer.

Metabolic heterogeneity and the tumor immunosuppressive microenvironment (TIME) of triple-negative breast cancer (TNBC) hinder therapeutic effectiveness. Although emerging metabolic therapy and immunotherapy show promise, they are limited by off-target effects and immune escape. Here, a redox-activatable, sequentially-releasing nanoparticle (AMANC@M) for tumor-targeted delivery of anticancer agents and CRISPR/Cas9 has been developed. AMANC@M can reverse the TIME through dual metabolic inhibition, thereby enhancing TNBC therapy. AMANC@M demonstrates excellent biosafety and targets tumors precisely through biomimetic hybrid membrane-mediated homologous homing and the enhanced permeability and retention (EPR) effect. Once internalized into tumor cells, the CRISPR/Cas9 system ("energy nanolock") is released through glutathione (GSH) cleavage and effectively knocks down the expression of lactate dehydrogenase A (LDHA) to suppress glycolysis. After peeling off of the gene editing shell, a newly synthesized targeted drug, CPI-Z2 ("nutrihijacker" and "energy nanolock"), is released in a controlled manner to block the mitochondrial tricarboxylic acid (TCA) cycle. Nitric oxide (NO) produced from loaded L-arginine enhances the efficiency of CPI-Z2 and reduces drug resistance. Combined with NO therapy, both blockades of nutrients and energy production transform the hypoxia and acidic TIME into an immunocompetent tumor microenvironment (TME) for tumor elimination. Furthermore, AMANC@M offers capabilities for photothermal (PT) therapy and provides clear imaging through PT, photoacoustic (PA), or computed tomography (CT) signals in tumor tissue. Thus, this study provides a new and promising sequentially stimuli-responsive targeting strategy for nanoparticle development, making it a potential treatment candidate for TNBC and other tumors.

Discovery of novel organoarsenicals as robust thioredoxin reductase inhibitors for oxidative stress mediated cancer therapy.

Targeting overexpressed thioredoxin reductase (TrxR) in cancer cells to induce oxidative stress has been proved to be an effective strategy for cancer therapy. However, the treatment was hindered by the low efficiency and frequent administration of TrxR inhibitors, and hence more potent TrxR inhibitors were urgently needed. Herein, we designed and synthesized a series of TrxR inhibitors based on arsenicals. Among these, compound 1d inhibited the proliferation of a variety of cancer cells at low micromolar concentrations and exhibited low toxicity to normal cells. Importantly, compound 1d induced the accumulation of reactive oxygen species (ROS) by inhibiting the TrxR activity, further causing the collapse of the redox system, mitochondrial dysfunction, endoplasmic reticulum (ER) stress, and DNA damage, followed by oxidative stress-induced cell apoptosis. In vivo data showed that, compared with the clinical TrxR inhibitor auranofin (AUR), compound 1d could more effectively eliminate tumors by 90 % at a dose of 1.5 mg/kg without any obvious side effects. These results indicated that compound 1d was a potent TrxR inhibitor against cancer.

Reprogramming Energy Metabolism with Synthesized PDK Inhibitors Based on Dichloroacetate Derivatives and Targeted Delivery Systems for Enhanced Cancer Therapy.

In many types of cancers, pyruvate dehydrogenase kinase (PDK) is abnormally overexpressed and has become a promising target for cancer therapy. However, few highly effective inhibitors of PDK have been reported to date. Herein, we designed and synthesized a series of PDK inhibitors based on dichloroacetate (DCA) and arsenicals. Of the 27 compounds, 1f demonstrated PDK inhibition with high efficiency at a cellular level (IC50 = 2.0 µM) and an enzyme level (EC50 = 68 nM), far more effective than that of DCA. In silico, in vitro, and in vivo studies demonstrated that 1f inhibited PDK, shifted the energy metabolism from aerobic glycolysis to oxidative phosphorylation, and induced cell apoptosis. Moreover, new 1f-loaded nanoparticles were developed, and the administration of high-drug-loading nanoparticles (0.15 mg/kg) caused up to 90% tumor shrinkage without any apparent toxicity. Hence, this study provided a novel metabolic therapy for cancer treatment.

Strategies for Cartilage Repair in Osteoarthritis Based on Diverse Mesenchymal Stem Cells-Derived Extracellular Vesicles.

Osteoarthritis (OA) causes disability and significant economic and social burden. Cartilage injury is one of the main pathological features of OA, and is often manifested by excessive chondrocyte death, inflammatory response, abnormal bone metabolism, imbalance of extracellular matrix (ECM) metabolism, and abnormal vascular or nerve growth. Regrettably, due to the avascular nature of cartilage, its capacity to repair is notably limited. Mesenchymal stem cells-derived extracellular vesicles (MSCs-EVs) play a pivotal role in intercellular communication, presenting promising potential not only as early diagnostic biomarkers in OA but also as efficacious therapeutic strategy. MSCs-EVs were confirmed to play a therapeutic role in the pathological process of cartilage injury mentioned above. This paper comprehensively provides the functions and mechanisms of MSCs-EVs in cartilage repair.

Identification of Peptides of Small Extracellular Vesicles from Bone Marrow-Derived Macrophages.

Small extracellular vesicles (sEVs) are typically secreted by the exocytosis of multivesicular bodies (MVBs). These nanovesicles with a diameter of <200 nm are present in various body fluids. These sEVs regulate various biological processes such as gene transcription and translation, cell proliferation and survival, immunity and inflammation through their cargos, such as proteins, DNA, RNA, and metabolites. Currently, various techniques have been developed for sEVs isolation. Among them, the ultracentrifugation-based method is considered the gold standard and is widely used for sEVs isolation. The peptides are naturally biomacromolecules with less than 50 amino acids in length. These peptides participate in a variety of biological processes with biological activity, such as hormones, neurotransmitters, and cell growth factors. The peptidome is intended to systematically analyze endogenous peptides in specific biological samples by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Here, we introduced a protocol to isolate sEVs by differential ultracentrifugation and extracted peptidome for identification by LC-MS/MS. This method identified hundreds of sEVs-derived peptides from bone marrow-derived macrophages.

NAT10-mediated RNA acetylation enhances HNRNPUL1 mRNA stability to contribute cervical cancer progression.

N4-acetylcytidine (ac4C) is a lately discovered nucleotide modification that has been shown to be closely implicated in cancer. N-acetyltransferase10(NAT10) acts as an enzyme that regulates mRNA acetylation modifications. Currently, the role of NAT10-mediated RNA acetylation modification in cervical cancer remains to be elucidated. On the basis of transcriptome analysis of TCGA and GEO open datasets (GSE52904, GSE29570, GSE122697), NAT10 is upregulated in cervical cancer tissues and correlated with poor prognosis. Knockdown of NAT10 suppressed the cell proliferation, invasion, and migration of cervical cancer cells. The in vivo oncogenic function of NAT10 was also confirmed in xenograft models. Combined RNA-seq and acRIP-seq analysis revealed HNRNPUL1 as the target of NAT10 in cervical cancer. NAT10 positively regulate HNRNPUL1 expression by promoting ac4C modification and stability of HNRNPUL1 mRNA. Furthermore, depletion of HNRNPUL1 suppressed the cell division, invasion, and migration of cervical cancer. HNRNPUL1 overexpression partially restored cellular function in cervical cancer cells with NAT10 knockdown. Thus, this study demonstrates that NAT10 contributes to cervical cancer progression by enhancing HNRNPUL1 mRNA stability via ac4C modification, and NAT10-ac4C-HNRNPUL1 axis might be a potential target for cervical cancer therapy.

Identification of Fangjihuangqi Decoction as a late-stage autophagy inhibitor with an adjuvant anti-tumor effect against non-small cell lung cancer.

BACKGROUND: Clinically, although chemotherapy is one of the most commonly used methods of treating tumors, chemotherapeutic drugs can induce autophagic flux and increase tumor cell resistance, leading to drug tolerance. Therefore, theoretically, inhibiting autophagy may improve the efficacy of chemotherapy. The discovery of autophagy regulators and their potential application as adjuvant anti-cancer drugs is of substantial importance. In this study, we clarified that Fangjihuangqi Decoction (FJHQ, traditional Chinese medicine) is an autophagy inhibitor, which can synergistically enhance the effect of cisplatin and paclitaxel on non-small cell lung cancer (NSCLC) cells. METHODS: We observed the changes of autophagy level in NSCLC cells under the effect of FJHQ, and verified the level of the autophagy marker protein and cathepsin. Apoptosis was detected after the combination of FJHQ with cisplatin or paclitaxel, and NAC (ROS scavenger) was further used to verify the activation of ROS-MAPK pathway by FJHQ. RESULTS: We observed that FJHQ induced autophagosomes in NSCLC cells and increased the levels of P62 and LC3-II protein expression in a concentration- and time-gradient-dependent manner, indicating that autophagic flux was inhibited. Co-localization experiments further showed that while FJHQ did not inhibit autophagosome and lysosome fusion, it affected the maturation of cathepsin and thus inhibited the autophagic pathway. Finally, we found that the combination of FJHQ with cisplatin or paclitaxel increased the apoptosis rate of NSCLC cells, due to increased ROS accumulation and further activation of the ROS-MAPK pathway. This synergistic effect could be reversed by NAC. CONCLUSION: Collectively, these results demonstrate that FJHQ is a novel late-stage autophagy inhibitor that can amplify the anti-tumor effect of cisplatin and paclitaxel against NSCLC cells.

Study of the Sensing Kinetics of G Protein-Coupled Estrogen Receptor Sensors for Common Estrogens and Estrogen Analogs.

Endogenous and exogenous estrogens are widely present in food and food packaging, and high levels of natural estrogens and the misuse or illegal use of synthetic estrogens can lead to endocrine disorders and even cancer in humans. Therefore, it is consequently important to accurately evaluate the presence of food-functional ingredients or toxins with estrogen-like effects. In this study, an electrochemical sensor based on G protein-coupled estrogen receptors (GPERs) was fabricated by self-assembly, modified by double-layered gold nanoparticles, and used to measure the sensing kinetics for five GPER ligands. The interconnected allosteric constants (Ka) of the sensor for 17ß-estradiol, resveratrol, G-1, G-15, and bisphenol A were 8.90 × 10-17, 8.35 × 10-16, 8.00 × 10-15, 5.01 × 10-15, and 6.65 × 10-16 mol/L, respectively. The sensitivity of the sensor for the five ligands followed the order of 17ß-estradiol > bisphenol A > resveratrol > G-15 > G-1. The receptor sensor also demonstrated higher sensor sensitivity for natural estrogens than exogenous estrogens. The results of molecular simulation docking showed that the residues Arg, Glu, His, and Asn of GPER mainly formed hydrogen bonds with -OH, C-O-C, or -NH-. In this study, simulating the intracellular receptor signaling cascade with an electrochemical signal amplification system enabled us to directly measure GPER-ligand interactions and explore the kinetics after the self-assembly of GPERs on a biosensor. This study also provides a novel platform for the accurate functional evaluation of food-functional components and toxins.

N6-methyladenosine-mediated gene regulation and therapeutic implications.

N6-methyladenosine (m6A) RNA methylation is the most abundant form of mRNA modification in eukaryotes and is at the front line of biological and biomedical research. This dynamic and reversible m6A RNA modification determines the fates of modified RNA molecules at the post-transcriptional level, affecting almost all important biological processes. Notably, m6A is also involved in chromatin and transcriptional regulation, while m6A dysregulation is implicated in various diseases. Here, we review current knowledge of post-transcriptional and transcriptional regulatory mechanisms involving m6A modification. We also discuss their involvement in the occurrence and development of diseases, including cancer, as well as potential theranostic targets, in hope of facilitating the translation of preclinical findings to the clinic.

Case Report: A case of synchronous right upper lobe adenocarcinoma and left lower lobe squamous cell carcinoma treated with immune checkpoint inhibitor plus chemotherapy.

Globally, lung cancer is the leading cause of cancer-related mortality. Multiple primary lung cancers (MPLC) account for a very small portion of all primary lung cancer cases. Importantly, a quick and precise differentiation between MPLC and intrapulmonary metastases is directly related to patient prognoses as treatment strategies vary according to pathological type. Synchronous MPLC are most commonly seen in the same lung. Here, we report a rare case of a patient with synchronous MPLC of both lungs. A 67-year-old man, with a 1-month cough and expectoration history, was admitted in our hospital. Computed tomography (CT) chest scan revealed a lower lobe nodule in the left lung and an upper lobe nodule in the right lung. He underwent successive fiberoptic bronchoscopy and CT-guided percutaneous pulmonary aspiration biopsy of both lungs. The pathological diagnosis was squamous cell carcinoma of the left lung and adenocarcinoma of the right lung.

Comparative Study on the Sensing Kinetics of Carbon and Nitrogen Nutrients in Cancer Tissues and Normal Tissues Based Electrochemical Biosensors.

In this study, an electrochemical sensor was developed by immobilizing colon cancer and the adjacent tissues (peripheral healthy tissues on both sides of the tumor) and was used to investigate the receptor sensing kinetics of glucose, sodium glutamate, disodium inosinate, and sodium lactate. The results showed that the electrical signal triggered by the ligand-receptor interaction presented hyperbolic kinetic characteristics similar to the interaction of an enzyme with its substrate. The results indicated that the activation constant values of the colon cancer tissue and adjacent tissues differed by two orders of magnitude for glucose and sodium glutamate and around one order of magnitude for disodium inosinate. The cancer tissues did not sense sodium lactate, whereas the adjacent tissues could sense sodium lactate. Compared with normal cells, cancer cells have significantly improved nutritional sensing ability, and the improvement of cancer cells' sensing ability mainly depends on the cascade amplification of intracellular signals. However, unlike tumor-adjacent tissues, colon cancer cells lose the ability to sense lactate. This provides key evidence for the Warburg effect of cancer cells. The methods and results in this study are expected to provide a new way for cancer research, treatment, the screening of anticancer drugs, and clinical diagnoses.

Numerical Simulation of Gas Explosion with Non-uniform Concentration Distribution by Using OpenFOAM.

Gas explosions in coal mines have occurred occasionally, which may cause casualties and economic losses. In the actual mine roadway, the gas concentration distribution is uneven because the gas density is lower than that of air. Gas explosion characteristics of uneven gas distribution with the concentration gradient in mine roadways were analyzed by using the open-source computational fluid dynamic code OpenFOAM. The flame and pressure characteristics were calculated, and the flame and shock wave propagation laws of the non-uniform gas-air mixture explosion with different concentration gradients were analyzed and compared with the uniform gas-air mixture gas. The results show that when the overall gas concentration is the same, the flame velocity and the pressure growth rate of the uniform gas explosion are lower than those of the non-uniform, but the pressure peaks of both are similar. At the same time, when the initial volume concentration is 10%, the non-uniform gas explosion has the highest flame propagation velocity and peak value. The peak explosion pressure of different concentration gradients is proportional to the initial concentration. The above studies clarified the characteristics of gas-air mixture explosions with concentration gradients and provided theoretical support for the prevention and control of gas explosion disasters.

Activating Wnt/ß-Catenin Signaling in Osteocytes Promotes Osteogenic Differentiation of BMSCs through BMP-7.

Bone formation is critically needed in orthopedic clinical practice. We found that, bone morphogenetic protein-7 (BMP-7) gene expression was significantly increased in fractured mice, which activates canonical Wnt signaling exclusively in osteocytes. Wnt and BMP signaling appear to exhibit synergistic or antagonistic effects in different kinds of cells. However, the communication between Wnt/ß-catenin signaling and BMP signaling in osteocytes is almost unknown. Our study verified in vitro that BMP-7 expression was significantly increased when Wnt signaling was activated in osteocytes. Next, BMP-7 in osteocytes was overexpressed using an adenovirus, the osteogenesis of bone marrow stem cells (BMSCs) was enhanced, when cocultured with osteocytes. On the contrary, BMP-7 in osteocytes was silenced using an adenovirus, the osteogenesis of bone marrow stem cells (BMSCs) was weakened. In addition, the osteogenesis of BMSCs was no longer promoted by Wnt-activated osteocytes when BMP-7 was silenced. Therefore, the results showed that BMP-7 mediated the anabolic actions of Wnt/ß-catenin signaling in osteocytes. Our study provides new evidence for the clinical application of BMP-7-overexpressed osteocytes.