The molecular mechanisms underlying lung metastasis of colorectal cancer (CRC) remain largely elusive, and effective therapeutic agents are still lacking. In this study, we identify levistilide A (LeA) as a potential anti-metastatic agent against CRC lung metastasis. We demonstrate that heat shock protein 90α (HSP90α) is markedly upregulated in CRC and promotes lung metastasis by suppressing ferroptosis. Notably, combined treatment with LeA and the ferroptosis inducer RSL3 further alleviates lung metastatic burden in vivo. Mechanistically, we reveal that the E3 ubiquitin ligase ring finger protein 40 (RNF40) suppresses CRC cell proliferation by directly interacting with HSP90α, inducing ubiquitination at lysine 407 and promoting its proteasomal degradation. RNF40-mediated HSP90α downregulation leads to the accumulation of malondialdehyde (MDA) and reactive oxygen species (ROS), thereby inhibiting CRC cell growth. Collectively, our findings provide mechanistic insights into how LeA directly targets HSP90α or facilitates RNF40-HSP90α-mediated degradation of HSP90α to regulate ferroptosis in CRC.
Retinal ischemia/reperfusion (I/R) injury is a major cause of vision loss, characterized by retinal edema and progressive retinal ganglion cell (RGC) death. Aquaporin-4 (AQP4), a water channel abundantly expressed in glial cells, plays a pivotal role in edema formation by regulating water homeostasis. Geranylgeranylacetone (GGA), a clinically approved anti-ulcer drug, functions as a potent and non-toxic inducer of heat shock protein 70 (HSP70) and has recently been implicated in the regulation of aquaporin trafficking. In parallel, the sorting nexin 27 (SNX27)-retromer complex is a key mediator of endosomal sorting and recycling of membrane proteins back to the plasma membrane, thereby maintaining their functional activity. In this study, we demonstrate that retinal I/R injury triggers altered subcellular localization of AQP4, with enhanced internalization compared with sham retinas. Concomitantly, SNX27-retromer expression was significantly upregulated at both mRNA and protein levels, and biochemical as well as imaging assays confirmed its interaction with AQP4. In a pre-ischemia dosing paradigm (prophylactic), GGA markedly attenuated retinal edema and RGC loss, and promoted the interaction between HSP70 and the SNX27-retromer complex. Importantly, GGA treatment reduced SNX27-retromer expression, thereby limiting AQP4 recycling to the plasma membrane and favoring its lysosome-associated trafficking. These effects were largely reversed by quercetin, a pharmacological inhibitor of HSP70, highlighting an HSP70-dependent mechanism. Together, our findings identify a previously unrecognized role of HSP70 in regulating SNX27-retromer-mediated AQP4 trafficking. By disrupting AQP4 recycling, GGA alleviates early retinal edema following I/R injury, providing mechanistic rationale for future therapeutic development.
BACKGROUND:Post-myocardial infarction (MI) cardiac fibrosis is a key driver of heart failure, with dysregulated cardiac metabolism playing a central role. The specific impact of circulating fatty acid metabolites on mitochondrial function and fibrotic remodeling remains unclear. Erucic acid, a very-long-chain fatty acid found in certain edible oils, has a historical association with cardiac lipidosis, yet its causal role and mechanism in post-MI fibrosis are unknown. METHODS:We employed an integrative, two-stage strategy. First, a hypothesis-free two-sample Mendelian Randomization (MR) analysis was performed using genome-wide association study (GWAS) data for 1400 serum metabolites and MI (FinnGen consortium) to identify causal risk metabolites. Second, the top-ranked metabolite, erucic acid, was functionally validated in vivo and in vitro. A murine MI model with graded dietary erucic acid supplementation was used to assess cardiac function, fibrosis, oxidative stress, mitochondrial ultrastructure, and energy metabolism. RNA-seq was performed to elucidate global pathway alterations. Complementary in vitro studies in TGF-β-stimulated HL-1 cardiomyocytes and in vivo AAV9-mediated cardiomyocyte-specific CD36 overexpression rescue experiments were conducted to dissect the molecular mechanism involving the CD36 lipid metabolism axis. RESULTS:MR analysis identified erucic acid as a putative causal risk metabolite for MI. In mice, erucic acid levels increased post-MI, and dietary supplementation dose-dependently exacerbated cardiac dysfunction, fibrosis, oxidative stress, and mitochondrial damage. High-dose erucic acid induced a severe metabolic shift, characterized by suppressed mitochondrial oxidative phosphorylation and enhanced glycolysis. In vitro, erucic acid suppressed the CD36 pathway and downstream lipid-handling enzymes, leading to aggravated lipid peroxidation (increased 4-HNE/rH2X, decreased SOD2). Crucially, in vitro CD36 overexpression rescued these detrimental metabolic and lipotoxic effects. Furthermore, in vivo cardiomyocyte-specific CD36 overexpression via AAV9-cTNT significantly attenuated erucic acid-induced cardiac fibrosis, mitochondrial damage, lipid peroxidation, and the glycolytic shift, firmly establishing CD36 as the central mediator. CONCLUSION:This study establishes erucic acid as a causal dietary metabolite that aggravates post-MI cardiac fibrosis. Its pathogenic mechanism involves the disruption of the cardioprotective CD36 lipid metabolism pathway, leading to mitochondrial dysfunction, lipotoxicity, and a detrimental bioenergetic shift. These findings highlight erucic acid and the CD36 axis as potential targets for risk stratification and dietary intervention following MI.
GlycoRNAs, newly identified RNA molecules bearing glycan modifications on cell membranes, are implicated in cell communication and immune regulation. However, current methodological limitations impede a thorough elucidation of their biological roles and clinical significance. Here, we developed Nucleotides Hybridization and Aptamer-based Proximity Ligation (NHAPL), a homogeneous assay enabling sensitive and quantitative RNA-associated glycan analysis from total cell RNA and serum. NHAPL integrates dual recognition by a sialic acid aptamer and RNA binding probe, followed by ligation and qPCR amplification. We further established multiplexed NHAPL for simultaneous detection of multiple RNA-associated glycan signals. Using this platform, we discovered that a subset of FNDC3B- and CTSS-derived 3'UTR fragments generate RNA-associated glycan signals and promote cell adhesion and migration. Importantly, serum RNA-associated glycan signals detected by NHAPL showed relatively low inter-individual variability among healthy individuals, whereas signals associated with Y5 and U1 RNAs were markedly elevated in patients with systemic lupus erythematosus in our cohort. The AUROC (area under the receiver operating characteristic curve) reached 1.000 for Y5-associated signals and 0.9977 for U1-associated signals in our cohort, supporting their potential as candidate biomarkers for systemic lupus erythematosus. The NHAPL platform requires no specialized instrumentation and enables rapid multiplexed detection of RNA-associated glycan signals. Owing to its simplicity, sensitivity, and flexibility, NHAPL provides a practical platform for profiling these signals and biomarker discovery. Overall, this work establishes NHAPL as a versatile analytical strategy for investigating RNA-associated glycan signals in biological samples.
Aging is an inevitable physiological process characterized by progressive functional decline and degenerative alterations across organ systems. Metabolic disturbance, particularly the disruption of substance and energy metabolism, is increasingly recognized as a central hallmark of aging. Emerging evidence suggests that dysregulation of the urea cycle (UC) contributes to aging-related pathological processes, including cognitive impairment; however, its role in astrocyte-mediated brain aging remains unclear. In this study, we used a D-galactose-induced mouse aging model to investigate the involvement of UC activation in age-related cognitive decline. Aging mice exhibited marked cognitive impairment, accompanied by an increased proportion of reactive astrocytes in the hippocampus, a key pathological feature of brain aging. Metabolic analysis and molecular validation revealed enhanced UC activity and increased urea production in aging mice. Inhibition of UC activation reduced urea production and decreased the proportion of hippocampal reactive astrocytes. Mechanistically, the expression of key UC-related enzymes, including ornithine decarboxylase 1 (ODC1) and arginase 1 (ARG1), was significantly downregulated, accompanied by improved mitochondrial dynamics, particularly the restoration of mitochondrial fusion and fission balance. Furthermore, ODC1 knockdown confirmed its critical role in mediating UC activation in astrocytes and significantly alleviated aging-like cellular phenotypes. Notably, Ganoderma lucidum polysaccharide peptides (GLPs) effectively suppressed UC activation in aging astrocytes by downregulating ODC1 and ARG1. Collectively, this study identifies dysregulated astrocytic UC activity as a novel metabolic mechanism linking astrocyte reactivity, mitochondrial dysfunction, and age-related cognitive decline, suggesting that targeting ODC1-mediated UC activation and mitochondrial dynamics may provide a promising dual strategy for combating brain aging.
Urea transporters (UTs) UT-As (encoded by Slc14A2) and UT-B (encoded by Slc14A1), are important members of the solute carrier family. They are a group of membrane channel proteins that are selectively permeable to urea. Slc14A1 is considered the key gene determining the Kidd blood group system, and its variants can lead to the loss of Jk antigens, resulting in transfusion-related complications. Additionally, studies have shown that Slc14A1 is closely associated with cancer development and progression, with its expression level and promoter methylation status potentially serving as biomarkers for cancer progression and prognosis. Recent research suggests that UT-B functional deficiency may cause neurodegenerative diseases by accumulating urea in the brain, thereby affecting neuronal function and viability. Mutations of Slc14A2 are linked to hypertension and metabolic syndrome, due to its essential role in maintaining urea homeostasis. This chapter aims to introduce the clinical significance of UT-B and UT-A and highlight their potential roles as diagnostic and therapeutic targets.
Parkinson’s disease (PD), common neurodegenerative disorder, involves substantia nigra dopaminergic neuron loss and α-synuclein accumulation in Lewy bodies. While pathogenesis remains unclear, dysregulated urea metabolism may play a central role. This study detected elevated serum urea levels in PD patients with upregulated urea cycle enzymes. In MPTP-induced PD mice, urea accumulated in the substantia nigra and striatum, alongside increased activity of urea cycle enzymes (ODC1, ARG1, OTC) and urea transporter UT-B. Mechanistically, brain urea accumulation likely stems from imbalanced urea cycle activity and impaired UT-B-mediated clearance, with compensatory UT-B upregulation specifically in the substantia nigra. In vitro, MPTP-treated neuronal cells showed increased enzyme and UT-B expression, while high urea directly suppressed tyrosine hydroxylase (TH). Importantly, ODC1 knockdown reversed urea dysmetabolism, restored TH, and alleviated neuronal damage. These findings establish ODC1-mediated urea cycle dysregulation as a core metabolic feature of PD, proposing ODC1 or urea metabolism as novel therapeutic targets.
Background: Argininosuccinate synthase 1 (ASS1), a key enzyme in arginine biosynthesis, is highly expressed in colorectal cancer (CRC) and promotes cancer progression, making it a potential therapeutic target. Evodiamine (EVO), a natural alkaloid from Evodia rutaecarpa acts as a novel Wnt signaling pathway inhibitor with strong anticancer activity against various cancers. However, its exact therapeutic mechanism in CRC remains unclear. Methods: To address this gap, experiments included enzyme-linked immunosorbent assay (ELISA) to test EVO’s effect on CRC arginine production; CCK-8, EdU, colony formation, and wound-healing assays to assess CRC cell proliferation and migration; RT-qPCR, Western blot, immunofluorescence (IF), and ShASS1 for mechanism exploration and target validation; and a syngeneic tumor allograft model to study EVO’s metabolic regulation and anticancer efficacy in CRC. Results: In vitro, EVO significantly inhibited arginine synthesis metabolism and reduced CRC cell proliferation/migration. In vivo, it suppressed tumor tissue arginine metabolism, slowed allograft tumor growth, and decreased ASS1 expression. Mechanistically, EVO concentration-dependently reduced ASS1 via the Wnt/β-catenin/c-MYC pathway; ShASS1 replicated EVO’s anticancer effects, confirming ASS1’s mediating role. Conclusions: EVO downregulates ASS1 via the Wnt/β-catenin/c-MYC pathway disrupts CRC arginine synthesis metabolism and inhibits CRC cell proliferation/migration. These results support the interaction between metabolic regulation and signaling pathways, highlighting EVO as a promising CRC therapeutic candidate.
Bilirubin encephalopathy (BE) is a neurological disorder caused by the accumulation of unconjugated bilirubin (UCB) in the brain of newborns, resulting in various degrees of neuronal impairment. BE is characterized by cytotoxic edema and neuronal apoptosis. Aquaporin-4 (AQP4), a water channel abundantly expressed in the central nervous system, plays a critical role in maintaining water homeostasis. Dysregulation of AQP4 expression or trafficking is closely associated with brain edema, suggesting that modulation of AQP4 may offer a potential therapeutic approach for BE. Previous studies have indicated that melatonin (MT) possesses neuroprotective and therapeutic potential against BE; however, its precise mechanisms remain unclear. In this study, we optimized rat BE model to investigate the therapeutic effects of melatonin on AQP4 expression, trafficking, and apoptosis in parietal cortical neurons. Furthermore, we explored the molecular mechanisms underlying melatonin’s neuroprotective actions, including the regulation mechanism of AQP4 expression, brain edema formation, and apoptosis induced by UCB accumulation. The results indicate that in the BE model, pathological injury of parietal cortex was significantly aggravated and AQP4’s expression peaked at 24 h after BE modeling. MT activated PI3K/AKT signaling pathway in rat parietal cortex to downregulate AQP4 expression, apoptosis related proteins, and decreased SNX27’s expression to promote the internalization of AQP4, reducing bilirubin induced cytotoxic edema and cortical apoptosis. This data suggest that MT has a neuroprotective role in BE, by potentially delaying its progression.
Background:The tumor microenvironment and biomarkers play a pivotal role in breast cancer research, yet there remains a pressing need for effective biomarkers. This study focuses on identifying a novel IGKC+ T Cell subpopulation and its related biomarkers to pave the way for innovative targeted therapies and improved clinical outcomes. Methods:We first performed single-cell RNA sequencing (scRNA-seq) analysis to characterize immune cell heterogeneity within the tumor microenvironment, leading to the identification of series cell subpopulation. Then, by performing univariate analysis to correlate cell proportions with patient prognosis, we identified a novel IGKC+ T cell subpopulation. Next, we applied bulk RNA-seq deconvolution algorithms to estimate the abundance of this subpopulation across breast cancer cohorts. Differential expression analysis and weighted gene co-expression network analysis (WGCNA) were employed to identify genes associated with the IGKC+ T cell population. To pinpoint key regulatory genes, we applied machine learning algorithms. Based on the hub genes identified, we constructed a prognostic risk model and developed a nomogram to aid clinical decision-making. Immune infiltration patterns were further assessed in high- vs low-risk groups defined by the model. Finally, functional validation was performed through overexpression of BCL2L14 in vitro, and downstream signaling pathways were examined. Results:We identified the novel IGKC+ T cell subpopulation and core genes. Machine learning pinpointed BCL2L14, IGHD, MAPT-AS1, NT5DC4, and TNIP3 as key regulators of breast cancer progression in this subpopulation. The model stratified patients into high- and low-risk groups, with high-risk patients showing worse prognosis and weaker immune infiltration. Overexpression of BCL2L14 was experimentally demonstrated to accelerate breast cancer progression, linked to enhanced phosphorylation of the NF-κB pathway. Conclusion:Our results underscore BCL2L14 as a potential driver within the novel T-cell subpopulation and a critical biomarker for breast cancer diagnosis. These findings provide a basis for developing advanced diagnostic tools and targeted therapies, which may ultimately enhance patient prognosis.
Currently, chemotherapy in colorectal cancer (CRC) often leads to the development of drug resistance and poor prognosis. Prior research has shown that Evodiamine (Evo) exhibits antitumor properties; however, it has not been well studied in reversing tumor multidrug resistance (MDR). Therefore, this study's main objective is to explore Evo's capacity to overcome the resistance exhibited by colorectal cancer cells towards 5-fluorouracil (5-FU) and uncover the molecular mechanisms that underlie this phenomenon. The impact of Evo/5-FU on cellular viability of colorectal cancer multidrug-resistance (MDR) cell lines was detected by CCK8 assay, and Evo on the cell cycle as well as apoptosis of multidrug-resistant (MDR) cells, both when Evo is administered alone and in combination with 5-FU. Based on the RNA-seq results, the possible targets of Evo were screened, the target genes were overexpressed and silenced, RT-qPCR validated the mRNA expression, Western blot validated protein expression, and the associated phenotypic experiments were verified. The synergistic effect of Evo on 5-FU was investigated using a colorectal cancer xenograft tumor model. The outcomes of in vivo and in vitro experiments demonstrated that low concentrations of Evo could markedly augment the growth inhibitory impact of 5-FU on CRC cells compared to the group treated with 5-FU alone. The mechanism potentially involves Evo targeting RRM2 to modulate the NF-κB and JAK2/STAT3 pathways, thereby augmenting chemotherapeutic drug-induced apoptosis. The findings suggest that Evo effectively reversed the multidrug resistance of HCT8/5-FU cells in vitro and in vivo by targeting RRM2. The study also offers novel evidence to support further exploration of the potential anticancer properties of Evo.
Aging represents a natural and inevitable physiological process characterized by the gradual deterioration in the functions of various organ systems. One of the central hallmarks of aging is the dysregulation of both substance and energy metabolism. Previous research has associated the urea cycle (UC) with the development of neurodegenerative diseases. In this study, we observed elevated levels of urea, the end-product of the UC, upregulation of urea cycle enzymes, and an increase of the side-product putrescine in the elderly serum and aging models, while the initial substrate ammonia remained unchanged. Notably, region-specific accumulation of neuronal urea and activation of the UC were associated with age-related deficits in cognitive and motor functions. Mechanistically, urea accumulation in the brain appears to stem from dysregulated UC activity coupled with compensatory clearance mediated by the urea transporter UT-B. Exposing neurons to high urea levels accelerated UC flux and induced cellular senescence. Importantly, pharmacological inhibition or knockdown of ornithine decarboxylase 1 (ODC1) ameliorated urea metabolic dysregulation and reduced neuronal damage. Together, these findings reveal a novel connection between dysregulated neuronal urea cycle activity and age-related neural impairment, linking metabolic reprogramming to neurodegenerative pathology. Our results not only uncover a key metabolic mechanism underlying brain aging but also provide a promising dual-target therapeutic strategy, highlighting the urea cycle as a potential intervention point for delaying neurodegenerative processes associated with aging.
High urea can induce depression and anxiety. Activation of astrocytes is closely associated with psychiatric disorders. However, the pathological mechanism of whether high urea affects astrocyte structure and function to induce anxiety-like behaviors remain unclear. We established a high-urea chronic kidney disease (CKD) mouse model and found that these mice exhibited elevated levels of anxiety through behavioral experiments. Immunofluorescence and transmission electron microscopy studies of astrocytes revealed a decrease in density and branching of mPFC astrocytes. Additionally, we observed a significant reduction in ATP and BDNF levels in the mPFC and primary astrocytes of CKD mice induced by high urea. Analysis of gene expression differences in astrocytes between WT and high-urea mice indicated alterations in mitochondrial dynamics-related signaling pathways in astrocytes. We established a high-urea primary astrocyte model to assess mitochondrial function and levels of fusion and fission proteins. Treatment of primary astrocytes with high urea led to mitochondrial fragmentation and downregulation of Mfn2 expression. These results suggested that high urea downregulates Mfn2 expression in mPFC astrocytes, induced mitochondrial fusion-fission abnormalities, disrupted astrocyte energy metabolism, and promoted high-urea-related anxiety. Mfn2 may represent a potential therapeutic target for high-urea-related anxiety.
Ferroptosis is a novel form of programmed cell death that is triggered by iron-dependent lipid peroxidation. Brusatol (BRU), a natural nuclear factor erythroid 2-related factor 2 inhibitor, exhibits potent anticancer effects in various types of cancer. However, the exact mechanism of BRU in the treatment of hepatocellular carcinoma (HCC) remains unknown. The anticancer effects of BRU in HCC were detected using cell counting kit-8 and colony formation assays and a xenograft model. RNA sequencing (RNA-seq) and bioinformatics analyses of HCC cells were utilized to elucidate the mechanism underlying the effects of BRU in HCC. The levels of reactive oxygen species (ROS), glutathione (GSH), malondialdehyde (MDA), and Fe 2+ were measured using assay kits. The expression of activating transcription factor 3 (ATF3) was tested using RT-qPCR, western blotting, and immunofluorescence staining. The role of ATF3 in BRU-induced ferroptosis was examined using siATF3. BRU significantly inhibited HCC cell proliferation, both in vitro and in vivo. BRU activated the ferroptosis signaling pathway and increased ATF3 expression. Furthermore, ATF3 knockdown impeded BRU-induced ferroptosis. BRU suppressed HCC growth through ATF3-mediated ferroptosis, supporting BRU as a promising therapeutic agent for HCC.
In the treatment of lumbar burst fractures with nerve injury, fusion is often required to rebuild spinal stability, but it can lead to the loss of motor units and increase the occurrence of adjacent segment diseases. Thus, a novel approach of lumbar canal decompression with "pedicle-plasty" strategy (DDP) was needed in clincal treatment. Firstly, image measurement analysis, the images of 60 patients with lumbar spine CT examinations were selected to measure osteotomy angle (OA), distance from the intersection of osteotomy plane and skin to the posterior midline (DM),transverse length of the osteotomy plane (TLOP), and sagittal diameter of the outer edge of superior articular process (SD). Secondary, cadaver study, distance between the intermuscular space and midline (DMSM), anterior and posterior diameters of the decompression (APDD), and lateral traction distance of the lumbosacral plexus (TDLP) were measured on 10 cadaveric specimens. Finally, procedure of DDP was demonstrated on cadaver specimens. OA ranged from 27.68°+4.59° to 38.34°+5.97°, DM ranged from 43.44+6.29 to 68.33+12.06 mm, TLOP ranged from 16.84+2.19 to 19.64+2.36 mm, and SD ranged from 22.49+1.74 to 25.53+2.21 mm. DMSM ranged from 45.53+5.73 to 65.46+6.43 mm. APDD were between 10.51+3.59 and 12.12+4.54 mm, and TDLP were between 3.28+0.81 and 6.27+0.62 mm.DDP was successfully performed on cadaveric specimens. DDP, as a novel approach of decompression of burst fractures with pedicle rupture, can fully relieve the occupation and at the same time preserve the spinal motor unit because of no resection of intervertebral discs and no destruction of facet joints,and has certain developmental significance.
Viruses can infiltrate the central nervous system and contribute to depression, which may include alterations in dopamine (DA) metabolism triggered by immune responses though the specific mechanisms involved remain unclear. Here, an electrochemical system to realize the real-time dynamic monitoring of DA with high sensitivity is proposed and it is demonstrated that the viral simulator polyinosinic-polycytidylic acid (poly(I:C)) can inhibit the release of DA (from 5.595 to 0.137 µm) in neurons from the perspective of single cells, cell populations and even in vivo through the combination of multiscale electrodes, including single nanowires, carbon fibers (CFs) and 2D flexible electrodes. These findings are associated with the increase in reactive oxygen species (ROS) produced by microglia. At the molecular level, poly(I:C) significantly decreases the expression of α-synuclein and increases its phosphorylation level, whereas ROS inhibitors can reverse these pathological changes and salvage DA release to half the initial level (≈2.6 µM). These results suggest that viruses may indirectly inhibit DA system function through ROS produced in inflammatory responses and that antioxidant activity may be a potential therapeutic strategy.
Evodiamine, a novel alkaloid, was isolated from the fruit of tetradium. It exerts a diversity of pharmacological effects and has been used to treat gastropathy, hypertension, and eczema. Several studies reported that evodiamine has various biological effects, including anti-nociceptive, anti-bacterial, anti-obesity, and anti-cancer activities. However, there is no research regarding its effects on drug-resistant cancer. This study aimed to investigate the effect of evodiamine on human vemurafenib-resistant melanoma cells (A375/R cells) proliferation ability and its mechanism. Cell activity was assessed using the cell counting kit-8 (CCK-8) method. Flow cytometry assay was used to assess cell apoptosis and cell cycle. A xenograft model was used to analyze the inhibitory effects of evodiamine on tumor growth. Bioinformatics analyses, network pharmacology, and molecular docking were used to explore the potential mechanism of evodiamine in vemurafenib-resistant melanoma. RT-qPCR and Western blotting were performed to reveal the molecular mechanism. The alkaloid extract of the fruit of tetradium, evodiamine showed the strongest tumor inhibitory effect on vemurafenib-resistant melanoma cells compared to treatment with vemurafenib alone. Evodiamine inhibited vemurafenib-resistant melanoma cell growth, proliferation, and induced apoptosis, conforming to a dose–effect relationship and time–effect relationship. Results from network pharmacology and molecular docking suggested that evodiamine might interact with IRS4 to suppress growth of human vemurafenib-resistant melanoma cells. Interestingly, evodiamine suppressed IRS4 expression and then inhibited PI3K/AKT signaling pathway, and thus had the therapeutic action on vemurafenib-resistant melanoma.
In this chapter, we mainly discuss the expression and function of aquaporins (AQPs) expressed in digestive system. AQPs are highly conserved transmembrane protein responsible for water transport across cell membranes. AQPs in gastrointestinal tract include four members of aquaporin subfamily: AQP1, AQP4, AQP5, and AQP8, and three members of aquaglyceroporin subfamily: AQP3, AQP7, and AQP10. In the digestive glands, especially the liver, we discuss four members of aquaporin subfamily: AQP1, AQP4, AQP5, and AQP8, three members of aquaglyceroporin subfamily: AQP7, AQP9, and AQP12. In digestive system, the abnormal expression of AQPs is closely related to the occurrence and development of a variety of diseases. AQP1 is involved in saliva secretion and fat digestion and is closely related to gastric cancer and chronic liver disease; AQP3 is involved in the diarrhea and inflammatory bowel disease; AQP4 regulates gastric acid secretion and is associated with the development of gastric cancer; AQP5 is relevant to gastric carcinoma cell proliferation and migration; AQP7 is the major aquaglyceroporin in pancreatic β cells; AQP8 plays a role in pancreatic juice secretion and may be a potential target for the treatment of diarrhea; AQP9 plays considerable role in glycerol metabolism and hepatocellular carcinoma; Studies on the function of AQP10 and AQP12 are still limited. Further studies are necessary for specific locations and functions of AQPs in digestive system.
Purpose: Due to poor prognosis and immunotherapy failure of skin cutaneous melanoma (SKCM), this study sought to find necroptosis-related biomarkers to predict prognosis and improve the situation with predicted immunotherapy drugs. Experimental Design: The Cancer Genome Atlas (TCGA) and The Genotype-Tissue Expression Program (GTEx) database were utilized to recognize the differential necroptosis-related genes (NRGs). Univariate Cox (uni-Cox) and least absolute shrinkage and selection operator (LASSO) Cox analysis were utilized for prognostic signature establishment. The signature was verified in the internal cohort. To assess the signature's prediction performance, the area under the curve (AUC) of receiver operating characteristic (ROC) curves, Kaplan-Meier (K-M) analyses, multivariate Cox (multi-Cox) regression, nomogram, and calibration curves were performed. The molecular and immunological aspects were also reviewed using single-sample gene set enrichment analysis (ssGSEA). Cluster analysis was performed to identify the different types of SKCM. Finally, the expression of the signature gene was verified by immunohistochemical staining. Results: On basis of the 67 NRGs, 4 necroptosis-related genes (FASLG, PLK1, EGFR, and TNFRSF21) were constructed to predict SKCM prognosis. The area's 1-, 3-, and 5-year OS under the AUC curve was 0.673, 0.649, and 0.677, respectively. High-risk individuals had significantly lower overall survival (OS) compared to low-risk patients. Immunological status and tumor cell infiltration in high-risk groups were significantly lower, indicating an immune system that was suppressed. In addition, hot and cold tumors could be obtained by cluster analysis, which is helpful for accurate treatment. Cluster 1 was considered a hot tumor and more susceptible to immunotherapy. Immunohistochemical results were consistent with positive and negative regulation of coefficients in signature. Conclusion: The results of this finding supported that NRGs could predict prognosis and help make a distinction between the cold and hot tumors for improving personalized therapy for SKCM.
M6A modification is an RNA-important processing event mediated by methyltransferases METTL3 and METTL14 and the demethylases. M6A dynamic changes after myocardial infarction (MI), involved in the massive loss of cardiomyocytes due to hypoxia, as well as the recruitment and activation of myofibroblasts. Balanced mitochondrial fusion and fission are essential to maintain intracardiac homeostasis and reduce poststress myocardial remodeling. Double-layer programmed drug release microneedle (DPDMN) breaks the limitations of existing therapeutic interventions in one period or one type of cells, and multitargeted cellular combination has more potential in MI therapy. By employing hypoxia-ischemic and TGF-β1-induced fibrosis cell models, we found that METTL3-14 inhibition effectively decreased cardiomyocyte death through the reduction of mitochondrial fragmentation and inhibiting myofibrillar transformation. DPDMN treatment of MI in rat models showed improved cardiac function and decreased infarct size and fibrosis level, demonstrating its superior effectiveness. The DPDMN delivers METTL3 inhibitor swiftly in the early phase to rescue dying cardiomyocytes and slowly in the late phase to achieve long-term suppression of fibroblast over proliferation, collagen synthesis, and deposition. RIP assay and mechanistic investigation confirmed that METTL3 inhibition reduced the translation efficiency of Drp1 mRNA by 5'UTR m6A modification, thus decreasing the Drp1 protein level and mitochondrial fragment after hypoxic-ischemic injury. This project investigated the efficacy of DPDMNs-loaded METTL3 inhibitor in MI treatment and the downstream signaling pathway proteins, providing an experimental foundation for the translation of the utility, safety, and versatility of microneedle drug delivery for MI into clinical applications.