ABSTRACT
Histones methyltransferase NSD3 targeting H3K36 is frequently disordered and mutant in various cancers, while the function of NSD3 during cancer initiation and progression remains unclear. In this study, it is proved that downregulated level of NSD3 is linked to clinical features and poor survival in lung adenocarcinoma. In vivo, NSD3 inhibited the proliferation, immigration, and invasion ability of lung adenocarcinoma. Meanwhile, NSD3 suppressed glycolysis by inhibiting HK2 translation, transcription, glucose uptake, and lactate production in lung adenocarcinoma. Mechanistically, as an intermediary, NSD3 binds to PPP1CB and p-STAT3 in protein levels, thus forming a trimer to dephosphorylate the level of p-STAT3 by PPP1CB, leading to the suppression of HK2 transcription. Interestingly, the phosphorylation function of PPP1CB is related to the concentration of carbon dioxide and pH value in the culture environment. Together, this study revealed the critical non-epigenetic role of NSD3 in the regulation of STAT3-dependent glycolysis, providing a piece of compelling evidence for targeting the NSD3/PPP1CB/p-STAT3 in lung adenocarcinoma.
ABSTRACT
A simple, efficient method has been described for the construction of an array of α-ketoamides from readily available O-benzoyl hydroxylamines and diazo compounds as starting materials. There was a combined use of CuI as a catalyst and H2O as the oxygen source. The investigation reveals that the O-benzoyl hydroxylamines serve a dual role as both an amine source and the oxidant in this mechanism, thereby obviating the need for additional oxidants in the transformation process. This methodology could give a wider range of products in good to excellent yields for most substrates, and thus, we provide a new idea for the synthesis of α-ketoamides.
ABSTRACT
BACKGROUND: Glioma is a type of malignant cancer that affect the central nervous system. New predictive biomarkers have been investigated in recent years, but the clinical prognosis for glioma remains poor. The function of CPLX2 in glioma and the probable molecular mechanism of tumor suppression were the focus of this investigation. METHODS: The glioma transcriptome profile was downloaded from The Cancer Genome Atlas (TCGA) and Chinese Glioma Genome Atlas (CGGA) databases for analysis of CPLX2 expression in glioma. RT-qPCR was performed to detect the expression of CPLX2 in 68 glioma subjects who have been followed up. Kaplan-Meier survival analyses were conducted to assess the effect of CPLX2 on the prognosis of glioma patients. The knockdown and overexpressed cell lines of CPLX2 were constructed to investigate the impact of CPLX2 on glioma. The cell growth, colony formation, and tumor formation in xenograft were performed. RESULTS: The expression of CPLX2 was downregulated in glioma and was negatively correlated with the grade of glioma. The higher expression of CPLX2 predicted a longer survival, as indicated by the analysis of Kaplan-Meier survival curves. Overexpressed CPLX2 impaired tumorigenesis in glioma progression both in vivo and in vitro. Knocking down CPLX2 promoted the proliferation of glioma cells. The analysis of GSEA and co-expression analysis revealed that CPLX2 may affect the malignancy of glioma by regulating the hypoxia and inflammation pathways. CONCLUSIONS: Our data indicated that CPLX2 functions as a tumor suppressor and could be used as a potential prognostic marker in glioma.
Subject(s)
Adaptor Proteins, Vesicular Transport , Brain Neoplasms , Glioma , Tumor Suppressor Proteins , Humans , Brain Neoplasms/genetics , Brain Neoplasms/metabolism , Brain Neoplasms/pathology , Glioma/genetics , Glioma/metabolism , Glioma/pathology , Kaplan-Meier Estimate , Prognosis , Transcriptome , Nerve Tissue Proteins/metabolism , Adaptor Proteins, Vesicular Transport/genetics , Adaptor Proteins, Vesicular Transport/metabolism , Tumor Suppressor Proteins/genetics , Tumor Suppressor Proteins/metabolismABSTRACT
BACKGROUND: RPLP2, an integral part of ribosomal stalk, plays an important role in the tumorigenesis of various cancers. However, its specific effect on HCC remains elusive. METHODS: TCGA, GTEx, HCCDB, HPA, UALCAN, MethSurv, TISIDB, K-M plotter, FerrDb, RNAactDrug, STRING, Cytoscape and R studio were conducted for bioinformatics analysis. RPLP2 expression level in HCC was verified by IHC and western blot. IHC was used to demonstrate the immune cell infiltration. Functional experiments including CCK8, transwell and colony formation assays, and nude mice xenograft model were performed for in vitro and in vivo validation. Western blot, IHC, CCK8 assay and detection of GSH and lipid ROS were adopted to determine the effect of RPLP2 on the ferroptosis of HCC cells. RESULTS: Here, we demonstrate that elevated level of RPLP2 is strongly associated with advanced clinicopathologic features, and predicts poor prognosis of HCC patients. Additionally, DNA methylation level of RPLP2 decreases in HCC, and significantly correlates with patients outcome. Moreover, high RPLP2 expression level is linked closely to the unfavorable immune infiltration. Most importantly, RPLP2 positively associates with ferroptosis suppressor GPX4, and inhibition of RPLP2 could lead to the acceleration of ferroptosis to suppress tumor progression of HCC. Last, drug sensitivity analysis predicts many drugs that potentially target RPLP2. CONCLUSION: Together, our study reveals previous unrecognized role of RPLP2 in HCC, and provides new regulatory mechanism of ferroptosis, indicating RPLP2 may be a novel therapeutic target for HCC.
ABSTRACT
Chronic obstructive pulmonary disease (COPD) is a significant global cause of morbidity and mortality currently. Long-term exposure of cigarette smoke (CS) inducing persistent inflammation, small airway remodeling and emphysematous lung are the distinguishing features of COPD. Ferroptosis, occurred in lung epithelial cells has recently been reported to be associated with COPD pathogenesis. DNA dioxygenase ten-eleven translocation 2 (TET2) is an important demethylase and its genetic mutation is associated with low forced expiratory volume in 1 s (FEV1) of lung function. However, its role in COPD remains elusive. Here, we found that TET2 regulates CS induced lipid peroxidation through demethylating glutathione peroxidase 4 (GPx4), thus alleviating airway epithelial cell ferroptosis in COPD. TET2 protein levels were mainly reduced in the airway epithelia of COPD patients, mouse models, and CS extract-treated bronchial epithelial cells. The deletion of TET2 triggered ferroptosis and further exaggerated CS-induced airway remodeling, inflammation, and emphysema in vivo. Moreover, we demonstrated that TET2 silencing intensified ferroptosis, while TET2 overexpression inhibited ferroptosis in airway epithelial cell treated with CSE. Mechanically, TET2 protected airway epithelial cells from CS-induced lipid peroxidation and ferroptosis through demethylating the promoter of glutathione peroxidase 4 (GPx4). Finally, co-administration of methylation inhibitor 5'-aza-2'-deoxycytidine (5-AZA) and the antioxidant N-acetyl-cysteine (NAC) have more protective effects on CS-induced COPD than either administration alone. Overall, our study reveals that TET2 is an essential modulator in the lipid peroxidation and ferroptosis of airway epithelial cell, and could act as a potential therapeutic target for CS-induced COPD.
Subject(s)
Cigarette Smoking , Dioxygenases , Ferroptosis , Pulmonary Disease, Chronic Obstructive , Mice , Animals , Humans , Ferroptosis/genetics , Cigarette Smoking/adverse effects , Phospholipid Hydroperoxide Glutathione Peroxidase/metabolism , Lung/metabolism , Pulmonary Disease, Chronic Obstructive/genetics , Epithelial Cells/metabolism , Inflammation/metabolism , DNA/metabolism , DNA-Binding Proteins/genetics , DNA-Binding Proteins/metabolism , Dioxygenases/metabolism , Dioxygenases/pharmacologyABSTRACT
Ferroptosis is characterized by the accumulation of lipid peroxidation driven by iron. As a regulated cell death, ferroptosis plays a critical role in various diseases and exhibits great therapeutic potentials. However, the mechanisms underlying ferroptosis, including its occurrence, execution, and regulation, remain poorly understood, which is necessary for developing effective therapeutic strategies. In this chapter, we summarize chromatin immunoprecipitation (ChIP) assay for the research of proteins-chromatin interactions. Moreover, Chromatin Isolation by RNA Purification (ChIRP) trial is introduced to investigate the interactions between lncRNA and chromatin. The application of ChIP and ChIRP is expected to explore the transcription and epigenetic regulation of ferroptosis deeply for therapeutic benefits.
Subject(s)
Ferroptosis , RNA, Long Noncoding , Chromatin/genetics , Ferroptosis/genetics , Epigenesis, Genetic , Chromatin Immunoprecipitation , Lipid Peroxidation , RNA, Long Noncoding/geneticsABSTRACT
Ferroptosis is characterized by the accumulation of lipid peroxidation as a unique iron-dependent cell death. However, the interplay between stemness and ferroptosis remains unknown. Here, we demonstrate that undifferentiated cells are more sensitive to ferroptosis than differentiated cells, and cystine transporter SLC7A11 protein is highly up-regulated by deubiquitinase DUBA in differentiated cells. Additionally, DUBA promotes stemness by deubiquitinating SLC7A11. Moreover, SLC7A11 drastically increases the expression of c-Myc through cysteine, the combination of sorafenib and c-Myc inhibitor EN4 has a synergetic effect on cancer therapy. Together, our results reveal that enhanced stemness increases the susceptibility to ferroptosis, and the DUBA-SLC7A11-c-Myc axis is pivotal for differentiated cancer stem cells (CSCs) resistant to ferroptosis, providing a promised targets to eradicate CSCs through ferroptosis.
Subject(s)
Ferroptosis , Humans , Ferroptosis/genetics , Cell Death , Cell Differentiation , Cysteine , Cystine , Amino Acid Transport System y+/geneticsABSTRACT
Epigenetic regulators and posttranslational modifications of proteins play important roles in various kinds of cancer cell death, including ferroptosis, a non-apoptotic form of cell death. However, the interplay of chromatin modifiers and deubiquitinase (DUB) in ferroptosis remains unclear. Here, we found that ubiquitin-specific protease 5 (USP5) is regarded as a bona fide DUB of lymphoid-specific helicase (LSH), a DNA methylation repressor, in hepatocellular carcinoma (HCC). Functional studies reveal that USP5 interacts with LSH and stabilizes LSH by a deubiquitylation activity-dependent process. Furthermore, the USP5-mediated deubiquitination of LSH facilitates the tumorigenesis of HCC by upregulating solute carrier family 7 member 11 (SLC7A11) to suppress ferroptosis of liver cancer cells. Moreover, the USP5 inhibitor degrasyn inhibits DUB activities of USP5 to LSH to suppress the progression of HCC. Additionally, USP5 and LSH are positively correlated and both are overexpressed and linked to poor prognosis in HCC patients. Together, our findings show that USP5 interacts with LSH directly and enhances LSH protein stability through deubiquitination, which, in turn, promotes the development of HCC by suppressing ferroptosis of liver cancer cells, suggesting that USP5 may be a potential therapeutic target for HCC.
ABSTRACT
Ferroptosis is an iron-dependent oxidative, nonapoptotic form of regulated cell death caused by the destruction of redox homeostasis. Recent studies have uncovered complex cellular networks that regulate ferroptosis. GINS4 is a promoter of eukaryotic G1/S-cell cycle as a regulator of initiation and elongation of DNA replication, but little is known about its impact on ferroptosis. Here, we found that GINS4 was involved in the regulation of ferroptosis in lung adenocarcinoma (LUAD). CRISPR/Cas9-mediated GINS4 KO facilitated ferroptosis. Interestingly, depletion of GINS4 could effectively induce G1, G1/S, S, and G2/M cells to ferroptosis, especially for G2/M cells. Mechanistically, GINS4 suppressed p53 stability through activating Snail that antagonized the acetylation of p53, and p53 lysine residue 351 (K351 for human p53) was the key site for GINS4-suppressed p53-mediated ferroptosis. Together, our data demonstrate that GINS4 is a potential oncogene in LUAD that functions to destabilize p53 and then inhibits ferroptosis, providing a potential therapeutic target for LUAD.
Subject(s)
Ferroptosis , Humans , Acetylation , Cell Cycle , Chromosomal Proteins, Non-Histone/metabolism , Oxidation-Reduction , Tumor Suppressor Protein p53/metabolism , Snail Family Transcription Factors/metabolismABSTRACT
Objective: Aryl hydrocarbon receptor (AhR) is a transcription factor. It is reported that AhR is associated with non-small cell lung cancer (NSCLC), but the mechanisms underlying this relationship remain unclear. Therefore, we investigated the role of AhR in NSCLC to elucidate the underlying mechanisms. Methods: We collected clinical lung cancer samples and constructed AhR overexpression and knockdown cell lines to investigate the tumorigenicity of AhR in vivo and in vitro. Furthermore, we performed a ferroptosis induction experiment and chromatin immunoprecipitation experiment. Results: AhR was highly expressed in NSCLC tissue. AhR knockdown cells showed ferroptosis related phenomenon. Furthermore, Chromatin immunoprecipitation confirmed the correlation between AhR and solute carrier family 7 member 11 (SLC7A11) and ferroptosis induction experiment confirmed that AhR affects ferroptosis via SLC7A11. Specifically, AhR regulates ferroptosis-related SLC7A11, which affects ferroptosis and promotes NSCLC progression. Conclusions: AhR promoted NSCLC development and positively correlated with SLC7A11, affecting its actions. AhR bound to the promoter region of SLC7A11 promotes NSCLC by activating SLC7A11 expression, improving the oxidative sensitivity of cells, and inhibiting ferroptosis. Thus, AhR affects ferroptosis in NSCLC by regulating SLC7A11, providing foundational evidence for novel ferroptosis-related treatments.
ABSTRACT
In the treatment of most malignancies, radiotherapy plays a significant role. However, the resistance of cancer cells to ionizing radiation (IR) is the main reason for the failure of radiotherapy, which causes tumor recurrence and metastasis. In this study, we confirmed that GPR162, an orphan receptor in the G-protein-coupled receptor family, acted as a novel radiotherapy sensitizer by interacting with the stimulator of interferon genes (STING), which targeted DNA damage responses, activated IRF3, accelerated the activation of type I interferon system, promoted the expression of chemokines including CXCL10 and CXCL4, and inhibited the occurrence and development of tumors. Interestingly, the activation of STING by overexpression of GPR162 was independent of the classical pathway of cGAS. STING inhibitors could resist the antitumor effect of overexpression of GPR162 in IR-induced mouse models. In addition, most solid tumors showed low expression of GPR162. And the higher expression of GPR162 indicated a better prognosis in patients with lung adenocarcinoma, liver cancer, breast cancer, etc. In summary, these results suggested that GPR162 may serve as a potential sensitizer of radiotherapy by promoting radiotherapy-induced STING-IFN production and increasing the expression of chemokines including CXCL10 and CXCL4 in DNA damage response, providing an alternative strategy for improving cancer radiotherapy.
Subject(s)
Interferon Type I , Neoplasms , Radiation-Sensitizing Agents , Mice , Animals , Signal Transduction/geneticsABSTRACT
We herein report the acid/base-steered two distinct reaction pathways of 2-acylbenzoic acids with isatoic anhydrides. In the presence of Na2CO3, the cascade process consists of the cyclization of 2-acetylbenzoic acid and nucleophilic ring-opening reaction of isatoic anhydride to furnish isobenzofuranone derivatives with high efficiency. However, p-toluenesulfonic acid can promote the product isobenzofuranones to undergo sequential intramolecular rearrangment, nucleophilic addition and cyclization reaction to produce diverse isoindolobenzoxazinones in good yields. The synthetic utility of this method was further demonstrated by the gram-scale preparation of the desired products and the facile transformations of the resulting products.
ABSTRACT
This review describes recent advances in copper-catalyzed difluoroalkylation reactions. The RCF2 radical is generally proposed in the mechanism of these reactions. At present, various types of copper-catalyzed difluoroalkylation reactions have been realized. According to their characteristics, we classify these difluoroalkylation reactions into three types.
Subject(s)
Copper , Cyclization , Catalysis , Molecular StructureABSTRACT
Liver cancer, a result of multifactorial interplay between heredity and the environment, is one of the leading causes of cancer-related death worldwide. Hepatocellular carcinoma (HCC) is the most common histologic type of primary liver cancer. Here, we reported that deficiency in PCDHB14, a member of the cadherin superfamily, participates in the progression of HCC. We found that PCDHB14 is inactivated by aberrant methylation of its promoter in HCC patients and that PCDHB14 functions as a tumor suppressor to promote cell cycle arrest, inhibit cell proliferation, and induce ferroptosis. Furthermore, PCDHB14 ablation dramatically enhanced diethylenenitrite-induced HCC development. Mechanistically, PCDHB14 is induced by p53, and increased PCDHB14 downregulates the expression of SLC7A11, which is critical for ferroptosis. This effect is mediated by accelerated p65 protein degradation resulting from PCDHB14 promoting E3 ubiquitin ligase RNF182-mediated ubiquitination of p65 to block p65 binding to the promoter of SLC7A11. This study reports the new discovery that PCDHB14 serves as a potential prognostic marker for HCC.
Subject(s)
Carcinoma, Hepatocellular , Ferroptosis , Liver Neoplasms , Protocadherins , Carcinoma, Hepatocellular/metabolism , Carcinoma, Hepatocellular/pathology , Cell Line, Tumor , Cell Proliferation/physiology , Humans , Liver Neoplasms/metabolism , Liver Neoplasms/pathology , Protocadherins/metabolism , UbiquitinationSubject(s)
Basic Helix-Loop-Helix Transcription Factors/genetics , L-Amino Acid Oxidase/genetics , Molecular Targeted Therapy , Neoplasms/therapy , Receptors, Aryl Hydrocarbon/genetics , Gene Expression Regulation, Neoplastic/genetics , Humans , Indoleamine-Pyrrole 2,3,-Dioxygenase/genetics , Neoplasms/genetics , Neoplasms/pathology , T-Lymphocytes, Regulatory/drug effectsABSTRACT
Ferroptosis is primarily caused by intracellular iron catalytic activity and lipid peroxidation. The potential interplay between ferroptosis and apoptosis remains poorly understood. Here, we show that the expression of a nuclear long non-coding RNA (lncRNA), LINC00618, is reduced in human leukemia and strongly increased by vincristine (VCR) treatment. Furthermore, LINC00618 promotes apoptosis by increasing the levels of BCL2-Associated X (BAX) and cleavage of caspase-3. LINC00618 also accelerates ferroptosis by increasing the levels of lipid reactive oxygen species (ROS) and iron, two surrogate markers of ferroptosis, and decreasing the expression of solute carrier family 7 member 11 (SLC7A11). Interestingly, VCR-induced ferroptosis and apoptosis are promoted by LINC00618, and LINC00618 accelerates ferroptosis in a manner dependent upon apoptosis. LINC00618 attenuates the expression of lymphoid-specific helicase (LSH), and LSH enhances the transcription of SLC7A11 after the recruitment to the promoter regions of SLC7A11, further inhibiting ferroptosis. Knowledge of these mechanisms demonstrates that lncRNAs related to ferroptosis and apoptosis are critical to leukemogenesis and chemotherapy.
Subject(s)
Apoptosis/genetics , Ferroptosis/genetics , RNA, Long Noncoding/genetics , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Biomarkers, Tumor , Cell Line, Tumor , Cell Nucleus , Ferroptosis/drug effects , Gene Expression , Gene Expression Regulation, Neoplastic , Humans , Protein Binding , Reactive Oxygen Species/metabolismABSTRACT
An exquisite protocol to the synthesis of erythrina-related structural derivatives was developed, which is composed of a nucleophilic addition of tertiary enamides to ketonic carbonyls and the trapping of acyliminium by an aromatic unit. This protocol afforded a powerful method for the construction of diverse fused N-pentacyclic skeletons in high efficiency and excellent diastereoselectivity by just using different acid catalysts.
ABSTRACT
Posttranslational modifications (PTMs) of proteins, including chromatin modifiers, play crucial roles in the dynamic alteration of various protein properties and functions including stem-cell properties. However, the roles of Lymphoid-specific helicase (LSH), a DNA methylation modifier, in modulating stem-like properties in cancer are still not clearly clarified. Therefore, exploring PTMs modulation of LSH activity will be of great significance to further understand the function and activity of LSH. Here, we demonstrate that LSH is capable to undergo PTMs, including methylation and phosphorylation. The arginine methyltransferase PRMT5 can methylate LSH at R309 residue, meanwhile, LSH could as well be phosphorylated by MAPK1 kinase at S503 residue. We further show that the accumulation of phosphorylation of LSH at S503 site exhibits downregulation of LSH methylation at R309 residue, which eventually promoting stem-like properties in lung cancer. Whereas, phosphorylation-deficient LSH S503A mutant promotes the accumulation of LSH methylation at R309 residue and attenuates stem-like properties, indicating the critical roles of LSH PTMs in modulating stem-like properties. Thus, our study highlights the importance of the crosstalk between LSH PTMs in determining its activity and function in lung cancer stem-cell maintenance.
Subject(s)
DNA Helicases/metabolism , Lung Neoplasms/enzymology , Neoplasm Proteins/metabolism , Neoplastic Stem Cells/enzymology , Animals , Cell Line, Tumor , DNA Helicases/genetics , Female , Humans , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Methylation , Mice , Mice, Nude , Neoplasm Proteins/genetics , Neoplastic Stem Cells/pathology , PhosphorylationABSTRACT
Cancer stem cells (CSCs) exhibit highly aggressive and metastatic features and resistance to chemotherapy and radiotherapy. Aryl hydrocarbon receptor (AhR) expression varies among non-small cell lung cancers (NSCLCs), and the mechanisms that support abnormal AhR expression in CSCs remain elusive. Here, we identified ubiquitin carboxyl terminal hydrolase L3 (UCHL3), a DUB enzyme in the UCH protease family, as a bona fide deubiquitylase of the AhR in NSCLC. UCHL3 was shown to interact with, deubiquitylate, and stabilize AhR in a manner dependent on its deubiquitylation activity. Moreover, we showed that UCHL3 promotes the stem-like characteristics and potent tumorigenic capacity of NSCLC cells. UCHL3 increased AhR stability and the binding of AhR to the promoter regions of the "stemness" genes ATP-binding cassette subfamily G member 2 (ABCG2), KLF4, and c-Myc. Depletion of UCHL3 markedly downregulated the "stemness" genes ABCG2, KLF4, and c-Myc, leading to the loss of self-renewal and tumorigenesis in NSCLCs. Furthermore, the UCHL3 inhibitor TCID induced AhR degradation and exhibited significantly attenuated efficacy in NSCLC cells with stem cell-like properties. Additionally, UCHL3 was shown to indicate poor prognosis in patients with lung adenocarcinoma. In general, our results reveal that the UCHL3 deubiquitylase is pivotal for AhR protein stability and a potential target for NSCLC-targeted therapy.