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Heliyon May 2024Hepatocellular carcinoma (HCC) is the most prevalent liver cancer. Despite of the improvement of therapies, the durable response rate and survival benefit are still...
BACKGROUND
Hepatocellular carcinoma (HCC) is the most prevalent liver cancer. Despite of the improvement of therapies, the durable response rate and survival benefit are still limited for HCC patients. It's urgent to clarify the molecular mechanisms and find therapeutic strategies to improve the clinical outcome. TNFα-stimulated gene-6 (TNFAIP6) plays a critical role in the prognosis of various tumors, but its roles in HCC are still unclear.
METHODS
Quantitative real-time PCR (qRT-PCR) and immunohistochemistry (IHC) analysis were employed to evaluate the clinical relevance of TNFAIP6 expressions in HCC patients. Cell counting kit-8 (CCK-8), Edu assay, and transwell assay were performed to evaluate the malignancy of HCC cells. Glucose uptake, lactate production, ATP production, extracellular acidification rate (ECAR) by Seahorse XF analyzer were employed to evaluate the role of TNFAIP6 in the regulation of aerobic glycolysis. The expressions of key proteins involved in glycolysis were examined by Western blot. Co-immunoprecipitation (Co-IP) and chromatin immunoprecipitation (ChIP) were used for protein-protein interactions or protein-RNA interactions respectively. Knockdown and overexpression of TNFAIP6 in HCC cells were employed for analyzing the functions of TNFAIP6 in HCC.
RESULTS
TNFAIP6 was significantly upregulated in HCC and predicted a poor clinical prognosis. Knockdown of TNFAIP6 inhibited cell proliferation, invasion, migration, as well as glycolysis in HCC cells. Mechanistically, we clarified that TNFAIP6 interacted with heterogeneous nuclear ribonucleoprotein C (HNRNPC), stabilized mRNA and upregulated pyruvate kinase M2 (PKM2) to promote glycolysis.
CONCLUSIONS
Our study reveals a molecular mechanism by which TNFAIP6 promotes aerobic glycolysis, which is beneficial for malignance of HCC and provides a potential clinical therapy for disease management.
PubMed: 38813227
DOI: 10.1016/j.heliyon.2024.e30959 -
Acta Pharmaceutica Sinica. B May 2024Cuproptosis shows enormous application prospects in lung metastasis treatment. However, the glycolysis, Cu efflux mechanisms, and insufficient lung drug accumulation...
Cuproptosis shows enormous application prospects in lung metastasis treatment. However, the glycolysis, Cu efflux mechanisms, and insufficient lung drug accumulation severely restrict cuproptosis efficacy. Herein, an inhalable poly (2-(-oxide-,-diethylamino)ethyl methacrylate) (OPDEA)-coated copper-based metal-organic framework encapsulating pyruvate dehydrogenase kinase 1 siRNA (siPDK) is constructed for mediating cuproptosis and subsequently promoting lung metastasis immunotherapy, namely OMP. After inhalation, OMP shows highly efficient lung accumulation and long-term retention, ascribing to the OPDEA-mediated pulmonary mucosa penetration. Within tumor cells, OMP is degraded to release Cu under acidic condition, which will be reduced to toxic Cu to induce cuproptosis under glutathione (GSH) regulation. Meanwhile, siPDK released from OMP inhibits intracellular glycolysis and adenosine-5'-triphosphate (ATP) production, then blocking the Cu efflux protein ATP7B, thereby rendering tumor cells more sensitive to OMP-mediated cuproptosis. Moreover, OMP-mediated cuproptosis triggers immunogenic cell death (ICD) to promote dendritic cells (DCs) maturation and CD8 T cells infiltration. Notably, OMP-induced cuproptosis up-regulates membrane-associated programmed cell death-ligand 1 (PD-L1) expression and induces soluble PD-L1 secretion, and thus synergizes with anti-PD-L1 antibodies (aPD-L1) to reprogram immunosuppressive tumor microenvironment, finally yielding improved immunotherapy efficacy. Overall, OMP may serve as an efficient inhalable nanoplatform and afford preferable efficacy against lung metastasis through inducing cuproptosis and combining with aPD-L1.
PubMed: 38799628
DOI: 10.1016/j.apsb.2024.01.017 -
Pharmaceuticals (Basel, Switzerland) Apr 2024Glycogen synthase kinase-3 (GSK-3) is a serine/threonine kinase which plays a center role in the phosphorylation of a wide variety of proteins, generally leading to...
Glycogen synthase kinase-3 (GSK-3) is a serine/threonine kinase which plays a center role in the phosphorylation of a wide variety of proteins, generally leading to their inactivation. As such, GSK-3 is viewed as a therapeutic target. An ever-increasing number of small organic molecule inhibitors of GSK-3 have been reported. Phenylmethylene hydantoins are known to exhibit a wide range of inhibitory activities including for GSK-3β. A family of fourteen 2-heterocycle substituted methylene hydantoins (, -) were prepared and evaluated for the inhibition of GSK-3β at 25 μM. The IC values of five of these compounds was determined; the two best inhibitors are 5-[(4'-chloro-2-pyridinyl)methylene]hydantoin (IC = 2.14 ± 0.18 μM) and 5-[(6'-bromo-2-pyridinyl)methylene]hydantoin (IC = 3.39 ± 0.16 μM). The computational docking of the compounds with GSK-3β (pdb 1q41) revealed poses with hydrogen bonding to the backbone at Val135. The 5-[(heteroaryl)methylene]hydantoins did not strongly inhibit other metalloenzymes, demonstrating poor inhibitory activity against matrix metalloproteinase-12 at 25 μM and against human carbonic anhydrase at 200 μM, and were not inhibitors for pyruvate carboxylase at concentrations >1000 μM.
PubMed: 38794140
DOI: 10.3390/ph17050570 -
Animals : An Open Access Journal From... May 2024Affected by the continuously rising temperature, thermal stress leads to a delinked growth rate and resistance to stress in cultured largemouth bass (, LMB) in China....
Affected by the continuously rising temperature, thermal stress leads to a delinked growth rate and resistance to stress in cultured largemouth bass (, LMB) in China. Identification of LMB with better thermal resistance will benefit the breeding of new varieties. However, there has been limited reporting on the evaluation to identify LMB with better thermal resistance. LMB consists of the northern LMB (, NLMB) and the Florida LMB (, FLMB). Due to their different geographical distributions, it has been suggested that FLMB exhibit better thermal resistance compared to NLMB. In this study, NLMB and FLMB were subjected to thermal stress for 3 h (acute) and 60 d (chronic) at 33 °C, respectively. Subsequently, the variations of 12 candidate biomarkers between NLMB and FLMB were analyzed. Exposure to acute thermal stress significantly increased plasma cortisol, blood glucose, and lactate levels; activities of superoxide dismutase (SOD), glutathione peroxidase (GPX), catalase (CAT), glucose kinase (GK), pyruvate kinase (PK), lactate dehydrogenase (LDH), and glucose 6 phosphatase (G6Pase); and the expressions of and in both NLMB and FLMB ( < 0.05). Compared to NLMB, FLMB exhibited a lower plasma cortisol level and a higher expression of under acute thermal stress ( < 0.05). Exposure to chronic thermal stress significantly increased plasma cortisol and blood glucose levels, as well as activities of GK, PK, LDH, and G6Pase, as well as expressions of and in both NLMB and FLMB ( < 0.05). Additionally, FLMB showed a lower expression of compared to NLMB ( < 0.05). In conclusion, our results showed that LMB with lower plasma cortisol level and higher expression of under acute thermal stress, as well as lower expression of under chronic thermal stress were suggested to have better thermal resistance. Our study provides valuable information for identifying and breeding LMB varieties with better thermal resistance in the future.
PubMed: 38791653
DOI: 10.3390/ani14101435 -
Metabolic Engineering May 2024Metabolic engineering for high productivity and increased robustness is needed to enable sustainable biomanufacturing of lactic acid from lignocellulosic biomass. Lactic...
Metabolic engineering for high productivity and increased robustness is needed to enable sustainable biomanufacturing of lactic acid from lignocellulosic biomass. Lactic acid is an important commodity chemical used for instance as a monomer for production of polylactic acid, a biodegradable polymer. Here, rational and model-based optimization was used to engineer a diploid, xylose fermenting Saccharomyces cerevisiae strain to produce L-lactic acid. The metabolic flux was steered towards lactic acid through the introduction of multiple lactate dehydrogenase encoding genes while deleting ERF2, GPD1, and CYB2. A production of 93 g/L of lactic acid with a yield of 0.84 g/g was achieved using xylose as the carbon source. To increase xylose utilization and reduce acetic acid synthesis, PHO13 and ALD6 were also deleted from the strain. Finally, CDC19 encoding a pyruvate kinase was overexpressed, resulting in a yield of 0.75 g lactic acid/g sugars consumed, when the substrate used was a synthetic lignocellulosic hydrolysate medium, containing hexoses, pentoses and inhibitors such as acetate and furfural. Notably, modeling also provided leads for understanding the influence of oxygen in lactic acid production. High lactic acid production from xylose, at oxygen-limitation could be explained by a reduced flux through the oxidative phosphorylation pathway. On the contrast, higher oxygen levels were beneficial for lactic acid production with the synthetic hydrolysate medium, likely as higher ATP concentrations are needed for tolerating the inhibitors therein. The work highlights the potential of S. cerevisiae for industrial production of lactic acid from lignocellulosic biomass.
PubMed: 38788894
DOI: 10.1016/j.ymben.2024.05.003 -
Cells May 2024Cells defend against oxidative stress by enhancing antioxidant capacity, including stress-activated metabolic alterations, but the underlying intracellular signaling...
Immunoglobulin Superfamily Containing Leucine-Rich Repeat (ISLR) Serves as a Redox Sensor That Modulates Antioxidant Capacity by Suppressing Pyruvate Kinase Isozyme M2 Activity.
Cells defend against oxidative stress by enhancing antioxidant capacity, including stress-activated metabolic alterations, but the underlying intracellular signaling mechanisms remain unclear. This paper reports that immunoglobulin superfamily containing leucine-rich repeat (ISLR) functions as a redox sensor that responds to reactive oxygen species (ROS) stimulation and modulates the antioxidant capacity by suppressing pyruvate kinase isozyme M2 (PKM2) activity. Following oxidative stress, ISLR perceives ROS stimulation through its cysteine residue 19, and rapidly degrades in the autophagy-lysosome pathway. The downregulated ISLR enhances the antioxidant capacity by promoting the tetramerization of PKM2, and then enhancing the pyruvate kinase activity, PKM2-mediated glycolysis is crucial to the ISLR-mediated antioxidant capacity. In addition, our results demonstrated that, in triple-negative breast cancer, cisplatin treatment reduced the level of ISLR, and PKM2 inhibition sensitizes tumors to cisplatin by enhancing ROS production; and argued that PKM2 inhibition can synergize with cisplatin to limit tumor growth. Our results demonstrate a molecular mechanism by which cells respond to oxidative stress and modulate the redox balance.
Topics: Humans; Oxidation-Reduction; Reactive Oxygen Species; Cell Line, Tumor; Antioxidants; Oxidative Stress; Animals; Cisplatin; Female; Membrane Proteins; Thyroid Hormones; Thyroid Hormone-Binding Proteins; Mice; Pyruvate Kinase; Glycolysis; Autophagy; Carrier Proteins; Triple Negative Breast Neoplasms
PubMed: 38786060
DOI: 10.3390/cells13100838 -
Biomolecules May 2024One of the hallmarks of cancer is metabolic reprogramming in tumor cells, and aerobic glycolysis is the primary mechanism by which glucose is quickly transformed into... (Review)
Review
One of the hallmarks of cancer is metabolic reprogramming in tumor cells, and aerobic glycolysis is the primary mechanism by which glucose is quickly transformed into lactate. As one of the primary rate-limiting enzymes, pyruvate kinase (PK) M is engaged in the last phase of aerobic glycolysis. Alternative splicing is a crucial mechanism for protein diversity, and it promotes precursor mRNA splicing to produce dominance, resulting in low expression. Specific splicing isoforms are produced in various tissues or illness situations, and the post-translational modifications are linked to numerous disorders, including cancers. hnRNPs are one of the main components of the splicing factor families. However, there have been no comprehensive studies on hnRNPs regulating alternative splicing. Therefore, this review focuses on the regulatory network of hnRNPs on pre-mRNA alternative splicing in tumors and clinical drug research. We elucidate the role of alternative splicing in tumor progression, prognosis, and the potential mechanism of abnormal RNA splicing. We also summarize the drug targets retarding tumorous splicing events, which may be critical to improving the specificity and effectiveness of current therapeutic interventions.
Topics: Humans; Alternative Splicing; Neoplasms; Heterogeneous-Nuclear Ribonucleoproteins; Pyruvate Kinase; Disease Progression; Gene Expression Regulation, Neoplastic; Animals
PubMed: 38785973
DOI: 10.3390/biom14050566 -
Current Issues in Molecular Biology May 2024Serine/arginine-rich splicing factors (SRSFs), part of the serine/arginine-rich (SR) protein family, play a crucial role in precursor RNA splicing. Abnormal expression...
Serine/arginine-rich splicing factors (SRSFs), part of the serine/arginine-rich (SR) protein family, play a crucial role in precursor RNA splicing. Abnormal expression of SRSFs in tumors can disrupt normal RNA splicing, contributing to tumor progression. Notably, SRSF7 has been found to be upregulated in hepatocellular carcinoma (HCC), yet its specific role and molecular mechanisms in HCC pathogenesis are not fully understood. We investigated the expression and prognostic significance of SRSF7 in HCC using bioinformatics database analysis. In HepG2 cells, the expressions of SRSF7 and glycolytic enzymes were analyzed using qRT-PCR, and Western blot. Glucose uptake and lactate production were quantified using relevant reagent kits. Additionally, cell proliferation, clonogenicity, invasion, and apoptosis were evaluated using MTS assay, clonal formation assay, Transwell assay, and mitochondrial membrane potential assay, respectively. This study demonstrated significant overexpression of SRSF7 in HCC tissue, correlating with poor prognosis. Knockdown of SRSF7 in HepG2 cells resulted in inhibited proliferation, clonogenicity, and invasion, while apoptosis was enhanced. This knockdown also decreased glucose uptake and lactate production, along with a reduction in the expression of glucose transporter 1 (GLUT1) and lactate dehydrogenase A (LDHA). Furthermore, SRSF7 downregulation increased the pyruvate kinase muscle 1 (PKM1)/PKM2 ratio. The glycolytic boost due to PKM2 overexpression partially counteracted the effects of SRSF7 silencing on HepG2 cell growth. The knockdown of SRSF7 impairs aerobic glycolysis and growth in HepG2 cells by downregulating PKM2 expression.
PubMed: 38785569
DOI: 10.3390/cimb46050301 -
Journal of Physiological Investigation Mar 2024Arteriosclerosis (AS) is a chronic inflammatory disease and Buyang Huanwu decoction (BHD) has been identified as an anti-atherosclerosis effect, and the study is aimed...
Arteriosclerosis (AS) is a chronic inflammatory disease and Buyang Huanwu decoction (BHD) has been identified as an anti-atherosclerosis effect, and the study is aimed to investigate the underlying mechanism. The E4 allele of Apolipoprotein E (ApoE) is associated with both metabolic dysfunction and an enhanced pro-inflammatory response, ApoE-knockout (ApoE-/-) mice were fed with a high-fat diet to establish an arteriosclerosis model and treated with BHD or atorvastatin (as a positive control). The atherosclerotic plaque in each mouse was evaluated using Oil red O Staining. Elisa kits were used to evaluate blood lipid, interleukin-6 (IL-6), IL-1 beta (IL-1β), tumor necrosis factor alpha (TNF-α), IL-4, IL-10, and tumor growth factor beta (TGF-β) contents, while Western blot was applicated to measure inducible nitric oxide synthase (iNOS), arginase I (Arg-1) expression. Meanwhile, pyruvate kinase M2 (PKM2), hypoxia-inducible factor-1 alpha (HIF-1α) and its target genes glucose transporter type 1 (GLUT1), lactate dehydrogenase A (LDHA), and 3-phosphoinositide-dependent kinase 1 (PDK1), as well as IL-6, IL-1β, TNF-α, IL-4, IL-10, and TGF-β were evaluated by the quantitative reverse transcription-polymerase chain reaction. BHD treatment significantly reduced body weight and arteriosclerosis plaque area and blood lipid levels including total cholesterol (TC), triglyceride (TG), low-density lipoprotein cholesterol (LDL-C), and high-density lipoprotein cholesterol (HDL-C). Meanwhile, BHD demonstrated a significant suppression of M1 polarization, by decreased secretion of iNOS and pro-inflammatory factors (IL-6, IL-1β, and TNF-α) in ApoE-/- mice. The present study also revealed that BHD promotes the activation of M2 polarization, characterized by the expression of Arg-1 and anti-inflammatory factors (IL-4 and IL-10). In addition, PKM2/HIF-1α signaling was improved by M1/M2 macrophages polarization induced by BHD. The downstream target genes (GLUT1, LDHA, and PDK1) expression was significantly increased in high fat feeding ApoE-/- mice, and those of which were recused by BHD and Atorvastatin. These results suggested that M1/M2 macrophages polarization produce the inflammatory response against AS progress after BHD exposure.
Topics: Animals; Drugs, Chinese Herbal; Mice; Atherosclerosis; Macrophages; Male; Apolipoproteins E; Disease Models, Animal; Mice, Knockout, ApoE; Mice, Knockout; Mice, Inbred C57BL; Cytokines
PubMed: 38780292
DOI: 10.4103/ejpi.EJPI-D-23-00040 -
International Journal of Medical... 2024Previous studies have highlighted the protective effects of pyruvate kinase M2 (PKM2) overexpression in septic cardiomyopathy. In our study, we utilized...
Previous studies have highlighted the protective effects of pyruvate kinase M2 (PKM2) overexpression in septic cardiomyopathy. In our study, we utilized cardiomyocyte-specific knockout mice to further investigate the role of PKM2 in attenuating LPS-induced myocardial dysfunction, focusing on mitochondrial biogenesis and prohibitin 2 (PHB2). Our findings confirmed that the deletion of in cardiomyocytes significantly exacerbated LPS-induced myocardial dysfunction, as evidenced by impaired contractile function and relaxation. Additionally, the deletion of intensified LPS-induced myocardial inflammation. At the molecular level, LPS triggered mitochondrial dysfunction, characterized by reduced ATP production, compromised mitochondrial respiratory complex I/III activities, and increased ROS production. Intriguingly, the absence of PKM2 further worsened LPS-induced mitochondrial damage. Our molecular investigations revealed that LPS disrupted mitochondrial biogenesis in cardiomyocytes, a disruption that was exacerbated by the absence of PKM2. Given that PHB2 is known as a downstream effector of PKM2, we employed PHB2 adenovirus to restore PHB2 levels. The overexpression of PHB2 normalized mitochondrial biogenesis, restored mitochondrial integrity, and promoted mitochondrial function. Overall, our results underscore the critical role of PKM2 in regulating the progression of septic cardiomyopathy. PKM2 deficiency impeded mitochondrial biogenesis, leading to compromised mitochondrial integrity, increased myocardial inflammation, and impaired cardiac function. The overexpression of PHB2 mitigated the deleterious effects of deletion. This discovery offers a novel insight into the molecular mechanisms underlying septic cardiomyopathy and suggests potential therapeutic targets for intervention.
Topics: Animals; Prohibitins; Cardiomyopathies; Mice; Myocytes, Cardiac; Mice, Knockout; Sepsis; Pyruvate Kinase; Mitochondria, Heart; Repressor Proteins; Humans; Organelle Biogenesis; Lipopolysaccharides; Male; Disease Models, Animal
PubMed: 38774750
DOI: 10.7150/ijms.94577