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Abstract Background Ginsenoside Rh2 (G-Rh2), a steroidal compound extracted from roots of ginseng, has been extensively studied in tumor therapy. However, its specific regulatory mechanism in non-small cell lung cancer (NSCLC) is not well understood. Pyruvate dehydrogenase kinase 4 (PDK4), a central regulator of cellular energy metabolism, is highly expressed in various malignant tumors. We investigated the impact of G-Rh2 on the malignant progression of NSCLC and how it regulated PDK4 to influence tumor aerobic glycolysis and mitochondrial function. Method We examined the inhibitory effect of G-Rh2 on NSCLC through I proliferation assay, migration assay and flow cytometry in vitro. Subsequently, we verified the ability of G-Rh2 to inhibit tumor growth and metastasis by constructing subcutaneous tumor and metastasis models in nude mice. Proteomics analysis was conducted to analyze the action pathways of G-Rh2. Additionally, we assessed glycolysis and mitochondrial function using seahorse, PET-CT, Western blot, and RT-qPCR. Result Treatment with G-Rh2 significantly inhibited tumor proliferation and migration ability both in vitro and in vivo. Furthermore, G-Rh2 inhibited the tumor’s aerobic glycolytic capacity, including glucose uptake and lactate production, through the HIF1-α/PDK4 pathway. Overexpression of PDK4 demonstrated that G-Rh2 targeted the inhibition of PDK4 expression, thereby restoring mitochondrial function, promoting reactive oxygen species (ROS) accumulation, and inducing apoptosis. When combined with sodium dichloroacetate, a PDK inhibitor, it complemented the inhibitory capacity of PDKs, acting synergistically as a detoxifier. Conclusion G-Rh2 could target and down-regulate the expression of HIF-1α, resulting in decreased expression of glycolytic enzymes and inhibition of aerobic glycolysis in tumors. Additionally, by directly targeting mitochondrial PDK, it elevated mitochondrial oxidative phosphorylation and enhanced ROS accumulation, thereby promoting tumor cells to undergo normal apoptotic processes.

Abstract Background Circular RNAs (circRNAs) are single-stranded RNAs with covalently closed structures that have been implicated in cancer progression. However, the regulatory mechanisms remain largely unclear. So, the aim of this study was to reveal the role and regulatory mechanisms of circ-SLC16A1. Methods In this study, next-generation sequencing was used to identify abnormally expressed circRNAs between cancerous and para-carcinoma tissues. Fluorescence in situ hybridization and quantitative reverse transcription polymerase chain reaction were performed to assess the expression patterns of circ-solute carrier family 16 member 1 (SLC16A1) in non-small cell lung cancer (NSCLC) cells and tissue specimens. The dual-luciferase reporter assay was utilized to identify downstream targets of circ-SLC16A1. Transwell migration, wound healing, 5-ethynyl-2′-deoxyuridine incorporation, cell counting, and colony formation assays were conducted to assess the proliferation and migration of NSCLC cells. A mouse tumor xenograft model was employed to determine the roles of circ-SLC16A1 in NSCLC progression and metastasis in vivo. Results The results found that circ-SLC16A1 was upregulated in NSCLC cells and tissues. Downregulation of circ-SLC16A1 inhibited tumor growth by reducing proliferation, lung metastasis, and lymphatic metastasis of NSCLC cells, and arrested the cell cycle in the G1 phase. Also, silencing of circ-SLC16A1 promoted apoptosis of NSCLC cells. The results of bioinformatics analysis and the dual-luciferase reporter assay confirmed that microRNA (miR)-1287-5p and profilin 2 (PFN2) are downstream targets of circ-SLC16A1. PFN2 overexpression or circ-SLC16A1 inhibition restored proliferation and migration of NSCLC cells after silencing of circ-SLC16A1. PFN2 overexpression restored migration and proliferation of NSCLC cells post miR-1287-5p overexpression. Conclusions Collectively, these findings show that miR-1287-5p/PFN2 signaling was associated with downregulation of circ-SLC16A1 and reduced invasion and proliferation of NSCLC cells. So, circ-SLC16A1 is identified as a mediator of multiple pro-oncogenic signaling pathways in NSCLC and can be targeted to suppress tumor progression.

Abstract Background Circular RNAs (circRNAs) belong to a class of covalently closed single stranded RNAs that have been implicated in cancer progression. Former investigations showed that hsa-circ-0013561 is abnormally expressed in head and neck squamous cell carcinoma (HNSCC). Nevertheless, the role of hsa-circ-0013561 during the progress of HNSCC still unclear. Methods Present study applied FISH and qRT-PCR to examine hsa-circ-0013561 expression in HNSCC cells and tissue samples. Dual-luciferase reporter assay was employed to identify downstream targets of hsa-circ-0013561. Transwell migration, 5-ethynyl-2′-deoxyuridine incorporation, CCK8 and colony formation assays were utilized to test cell migration and proliferation. A mouse tumor xenograft model was utilized to determine the hsa-circ-0013561 roles in HNSCC progression and metastasis in vivo. Results We found that hsa-circ-0013561 was upregulated in HNSCC tissue samples. hsa-circ-0013561 downregulation inhibited HNSCC cell proliferation and migration to promote apoptosis and G1 cell cycle arrest. The dual-luciferase reporter assay revealed that miR-7-5p and PDK3 are hsa-circ-0013561 downstream targets. PDK3 overexpression or miR-7-5p suppression reversed the hsa-circ-0013561-induced silencing effects on HNSCC cell proliferation and migration. PDK3 overexpression reversed miR-7-5p-induced effects on HNSCC cell proliferation and migration. Conclusion The findings suggest that hsa-circ-0013561 downregulation inhibits HNSCC metastasis and progression through PDK3 expression and miR-7-5p binding modulation.

Abstract Intercellular communication often relies on exosomes as messengers and is critical for cancer metastasis in hypoxic tumor microenvironment. Some circular RNAs (circRNAs) are enriched in cancer cell‐derived exosomes, but little is known about their ability to regulate intercellular communication and cancer metastasis. Here, by systematically analyzing exosomes secreted by non‐small cell lung cancer (NSCLC) cells, a hypoxia‐induced exosomal circPLEKHM1 is identified that drives NSCLC metastasis through polarizing macrophages toward to M2 type. Mechanistically, exosomal circPLEKHM1 promoted PABPC1‐eIF4G interaction to facilitate the translation of the oncostatin M receptor (OSMR), thereby promoting macrophage polarization for cancer metastasis. Importantly, circPLEKHM1‐targeted therapy significantly reduces NSCLC metastasis in vivo. circPLEKHM1 serves as a prognostic biomarker for metastasis and poor survival in NSCLC patients. This study unveils a new circRNA‐mediated mechanism underlying how cancer cells crosstalk with macrophages within the hypoxic tumor microenvironment to promote metastasis, highlighting the importance of exosomal circPLEKHM1 as a prognostic biomarker and therapeutic target for lung cancer metastasis.

Abstract The type parameter helps in scattering mechanism analysis and scattering centre identification. However, current approximate solution methods based on spectral estimation are noise‐sensitive and exhibit low accuracy. In this letter, a high‐precision approach for the type parameter based on the alternating direction method of multipliers (ADMM) is proposed. Logarithmic transformation is used to separate the type parameter and the amplitude from the coupling term, and initially obtain the closed‐form solution of the type parameter. Then, the regularization term of l2‐norm is used for denoising. Finally, a joint optimization model based on ADMM is constructed to effectively estimate the type parameter. Simulation results confirm the high accuracy of the proposed approach.

A major driving force behind China’s low-carbon, environmentally friendly development of agriculture and the accomplishment of the “dual-carbon” goal is the digital transformation of rural areas. In this study, on the basis of clarifying the degree of rural digitization and agricultural carbon emissions efficiency in China from 2010 to 2021, the degree of coupled coordination and the spatiotemporal pattern characteristics between the two are examined using the coupled coordination model. Then, the influencing factors are analyzed in depth using the spatial Durbin model. Our findings reveal that, first, in terms of the degree of rural digitization, the index increases overall and the spatial imbalance is obvious, with a spatial distribution pattern of “high in the east and low in the west”. Regarding the efficiency of agricultural carbon emissions, there is an overall “N-shaped” change, which is mainly influenced by technological progress in agricultural production, and the regional annual averages are, in descending order, the Western, Eastern, Northeastern, and Central regions, with obvious regional differences. Second, the coupling coordination index shows a fluctuating upward trend, from “extreme disorder” to “high-level coordination”. Furthermore, there are obvious regional characteristics. The regional growth rates are, in descending order, the Western, Eastern, Central, and Northeastern regions. Third, coupling coordination is jointly influenced by a variety of factors, including government input, educational level, industrial structure, energy use, urbanization rate, living standards, driving temporal patterns, and regional differences. This study not only helps to clarify the relationship between the two, offering a reference for the realization of the “dual-carbon” goal, but also broadens the concepts of the low-carbon and environmentally friendly development of agriculture.

Lung cancer is the main cause of cancer-related deaths, and non-small cell lung cancer (NSCLC) is the most common type. Understanding the potential mechanisms, prognosis, and treatment aspects of NSCLC is essential. This study systematically analyzed the correlation between mitophagy and NSCLC. Six mitophagy-related feature genes (SRC, UBB, PINK1, FUNDC1, MAP1LC3B, and CSNK2A1) were selected through machine learning and used to construct a diagnostic model for NSCLC. These feature genes are closely associated with the occurrence and development of NSCLC. Additionally, NSCLC was divided into two subtypes using unsupervised consensus clustering, and their differences in clinical characteristics, immune infiltration, and immunotherapy were systematically analyzed. Furthermore, the interaction between mitophagy-related genes (MRGs) and immune cells was analyzed using single-cell sequencing data. The findings of this study will contribute to the development of potential diagnostic biomarkers for NSCLC and the advancement of personalized treatment strategies.

Abstract Background Circular RNAs (circRNAs) are a new family of abundant regulatory RNAs with roles in various types of cancer. While the hsa_circ_0046701 (circ-YES1) function in non-small cell lung cancer (NSCLC) is unclear. Methods Circ-YES1 expression in normal pulmonary epithelial and NSCLC cells was examined. The small interfering RNA for circ-YES1 was prepared, cell proliferation and migration were assessed. Tumorigenesis in nude mice was assayed to validate the role of circ-YES1. Bioinformatics analyses and luciferase reporter assays were utilized to identify downstream targets of circ-YES1. Results Compared to normal pulmonary epithelial cells, the circ-YES1 expression increased in NSCLC cells, and cell proliferation and migration were suppressed after circ-YES1 knockdown. Both high mobility group protein B1 (HMGB1) and miR-142-3p were found to be downstream targets of circ-YES1, and miR-142-3p inhibition and HMGB1 overexpression reversed the effects of circ-YES1 knockdown on cell proliferation and migration. Similarly, HMGB1 overexpression reversed the miR-142-3p overexpression effects on these two processes. The imaging experiment results revealed that circ-YES1 knockdown impeded tumor development and metastasis in a nude mouse xenograft model. Conclusion Taken together, our results show that circ-YES1 promotes tumor development through the miR-142-3p–HMGB1 axis and support the development of circ-YES1 probability as a new therapeutic NSCLC target.

Abstract Dysregulation of circular RNAs (circRNAs) has recently been found to play an important role in the progression and development of cancers such as non-small cell lung cancer (NSCLC). Yet the functions of many circRNAs in NSCLC remain unclear. In this study, the circRNA expression profiles in NSCLC tumor tissues and adjacent non-tumorous tissues were detected by high-throughput sequencing. Bioinformatics analyses, the dual-luciferase reporter system, fluorescence in situ hybridization (FISH) and miRNA/mRNA high-throughput sequencing were used to identify circ-EPB41 and its downstream target. The subcutaneous tumor/caudal vein transfer mouse model was used for tumor growth and invasion analysis. The results show that the circ-EPB41 was upregulated in NSCLC tissues and cell lines. Increased circ-EPB41 expression in NSCLC was significantly correlated with malignant characteristics, and positive to post-surgical overall survival of NSCLC patients. Reduced circ-EPB41 expression in NSCLC decreased cell proliferation and invasion in both in vitro and in vivo experiments. The miRNA/mRNA high-throughput sequencing suggested that downregulation of circ-EPB41 promoted microRNA (miR)-486-3p and suppressed eukaryotic translation initiation factor 5A (eIF5A) expression. Luciferase reporter experiments confirmed that miR-486-3p/eIF5A were downstream targets of circ-EPB41. In addition, we also found that downregulation of circ-EPB41 suppressed self-renewal and decreased expression of stemness markers SOX2, OCT-4, Nanog and CD133 by sponging miR-486-3p to enhance eIF5A expression. Taken togeter, these data revealed the important role of circ-EPB41 in regulating NSCLC cell invasion and proliferation by modifying miR-486-3p/eIF5A axis-mediated stemness. We believe our study provides a novel perspective regarding the role of circRNAs in NSCLC progression.

The remote and non-contact monitoring of human respiration and heartbeat based on radars is a safe and convenient practice. However, how to accurately estimate the heart rate is still an open issue, because the heartbeat information in radar signals is affected by respiratory harmonics. In this paper, a maximum likelihood estimation was introduced to extract the heart rate from high-pass-filtered radar heartbeat waveforms where the low-frequency respiratory and heartbeat components were attenuated. The closed-form asymptotic estimation variance of the maximum likelihood estimator was derived to describe its performance in white Gaussian noise with a high signal-to-noise ratio (SNR). The proposed method was verified using two publicly available datasets and demonstrated superior performance compared to other methods. The estimation method and the asymptotic estimation variance here described are also applicable for signal period estimation in other settings with similar conditions.

Emerging studies showed that α-hederin induced autophagic cell death in different cancers via reactive oxygen species. Nevertheless, α-hederin role in non-small-cell lung cancer (NSCLC) remains unknown. So, the aim of this study was to explain whether ferroptosis is a therapeutic strategy to NSCLC, and to explore the effect of α-hederin on NSCLC ferroptosis. Current investigation found that α-hederin inhibited NSCLC cell proliferation, invasion, and migration in vitro and in vivo at toxic doses. The α-hederin treatment also increased NSCLC cell chemosensitivity to cisplatin and promoted ferroptosis and apoptosis at a safe dose. Proteomics, metabolomics, and high-throughput sequencing detection confirmed that α-hederin treatment downregulated glutathione peroxidase 2 (GPX2), and glutathione synthase (GSS) expression suppressed the synthesis of glutathione (GSH), which destroyed the GSH redox system. Eventually, it led to ferroptosis, apoptosis, and membrane permeabilization in NSCLC. Taken together, the study provided molecular data to confirm that α-hederin induced ferroptosis, apoptosis, and membrane permeabilization in NSCLC by destroying the GSS/GSH/GPX2 axis–mediated GSH oxidation-reduction system at a safe and low-toxicity dose.

Abstract A growing number of circular RNAs (circRNAs) have been identified and verified in several cancers. However, highly efficient therapeutic methods based on circRNAs in lung cancer remain largely unexplored. In the present study, we identified a novel circular RNA, hsa_circ_103820, based on Gene Expression Omnibus (GEO) data. Functionally, overexpression of hsa_circ_103820 showed significant inhibitory effects on the proliferation, migration and invasion of lung cancer cells, and knockdown of hsa_circ_103820 played promoting roles. Regarding the mechanism, we revealed that miR-200b-3p was a direct target of hsa_circ_103820 and that LATS2 and SOCS6 were the downstream target genes of miR-200b-3p. Therefore, we identified a novel potential tumor suppressive function of hsa_circ_103820 in lung cancer.

Abstract Background Bladder cancer (BC) is a common genitourinary malignancy worldwide. Circular RNAs (circRNAs) participate in cancer development, including BC; thus, the roles of circRNAs in this process have attracted significant attention. Methods In this study, high-throughput sequencing was used to analyze circRNA expression profiles in BC tissues. We performed RT-qPCR to determine hsa_circ_0001944 expression in BC tissues. We used fluorescence in situ hybridization (FISH) to detect hsa_circ_0001944 expression and hsa_circ_0001944 subcellular localization in BC tissues. hsa_circ_0001944 expression in BC cells was selectively regulated. We employed CCK8, transwell, and wound healing assays to monitor cell proliferation, invasion, and migration, respectively. We employed the dual-luciferase reporter and RNA pulldown assays to verify the relationships among hsa_circ_0001944, miR-548, and PROK2. We examined the effects of hsa_circ_0001944 on BC cell metastasis and proliferation in vivo using a subcutaneous xenograft model and an intravenous tail injection model in nude mice. Results The results showed that hsa_circ_0001944 expression was significantly increased in BC samples. Furthermore, high hsa_circ_0001944 expression predicted unfavorable prognoses in BC. Functional assays validated that downregulating hsa_circ_0001944 decreased BC invasion and proliferation in vivo and in vitro. Further studies showed that hsa_circ_0001944 expression promoted BC progression via sponging miR-548 and enhancing PROK2 expression. Luciferase reporter experiments validated the interactions between hsa_circ_0001944, miR-548, and PROK2. This study also found that downregulating miR-548 or overexpressing PROK2 restored BC cell invasion and proliferation after silencing hsa_circ_0001944. Conclusions Taken together, we found that hsa_circ_0001944 is a tumor-promoting circRNA in BC that functions as a competing endogenous RNA to regulate PROK2 expression via sponging miR-548.

This article has been retracted. Please see the Retraction Notice for more detail: https://doi.org/10.1186/s13046-020-01697-6.

Non-small-cell lung cancer (NSCLC) is one of the deadliest cancers in the world. Circular RNA (circRNA) has been shown to participate in oncogenesis regulation, including lung cancer. Although the involvement of circRNAs in lung cancer has been reported, the regulatory mechanisms of circRNAs in NSCLC remain poorly understood. Thus, the present study aims at investigating the role of circARHGAP10 in NSCLC progression, which has been observed to be significantly upregulated in both NSCLC tissues and cell lines with profile analysis. A higher expression of circARHGAP10 also leads to a poor prognosis in NSCLC patients with fluorescence in situ hybridization (FISH). Both in vitro and in vivo experiments found that the downregulation of circARHGAP10 suppressed glycometabolism by decreasing GLUT1 expression. Silencing circARHGAP10 also suppressed proliferation and metastasis by targeting the miR-150-5p/GLUT1 axis in NSCLC, which was confirmed with a luciferase reporter assay. Overexpression of GLUT1 or downregulation miR-150-5p will recover NSCLC cell proliferation and metastasis after a knockdown of circARHGAP10. Taken together, these findings demonstrate that circARHGAP10 suppresses NSCLC progression by acting as a miR-150-5p sponge to promote GLUT1 expression. Thus, circARHGAP10 may be a potential target for NSCLC treatment. Keywords: circRNA ARHGAP10, miR-150-5p, GLUT-1, non-small-cell lung cancer, high-throughput RNA sequencing

Corosolic acid is a pentacyclic triterpenoid isolated from Lagerstroemia speciosa, which is known to inhibit cancer cell proliferations. Whereas, the role of this compound on non-small cell lung cancer (NSCLC) cells still largely unclear. So, the aim of this study was to reveal the regulatory mechanism of corosolic acid to NSCLC. Here, we cultured A549 and PC9 cells in increasing corosolic acid concentrations, as well as treated mice with a physiologically relevant concentration of the compound, and used metabolomics analysis and high-throughput sequencing to examine its influences on cell invasion and proliferation, chemoresistance, and metastasis. We found that corosolic acid inhibited cell invasion and proliferation in vivo and in vitro, as well as increase the chemosensitivity of both cell types to cisplatin. Furthermore, we found that corosolic acid destabilized the glutathione peroxidase 2-mediated redox system, which increased mitochondrial and liposomal oxidative stress. Corosolic acid also decreased the targeting protein for TPX2 level, which inhibited PI3K/AKT signaling and induced apoptosis. In addition, the accumulation of reactive oxygen species dissociated the CCNB1/CDK1 complex and induced G2/M cell cycle arrest. Taken collectively, the data indicate that corosolic acid reduces NSCLC cell invasion and proliferation, as well as chemoresistance, by inducing mitochondrial and liposomal oxidative stress.

Achilles tendon rupture prognosis is usually unsatisfactory. After the tendon is injured, it may not function properly because of the fibrotic healing response, which restrains tendon motion. Inflammatory monocytes and tissue-resident macrophages are indispensable regulators in tissue repair, fibrosis, and regeneration. Exosomes from macrophages are crucial factors in tissue microenvironment regulation following tissue injury. This study therefore aimed to clarify the roles of macrophage exosomes in tendon injury (TI) repair. The results show that macrophages play a role after TI. M1 macrophages were increased relative to peritendinous fibrosis after TI. High-throughput sequencing showed abnormal expression of circular RNAs (circRNAs) between exosomes from M2 and M0 macrophages. Among the abnormal expressions of circRNA, circRNA-Ep400 was significantly increased in M2 macrophage exosomes. The results also show that M2 macrophage-derived circRNA-Ep400-containing exosomes are important for promoting peritendinous fibrosis after TI. Bioinformatics and dual-luciferase reporting experiments confirmed that miR-15b-5p and fibroblast growth factor (FGF)-1/7/9 were downstream targets of circRNA-Ep400. High circRNA-Ep400-containing exosome treatment inhibited miR-15b-5p, but promoted FGF1/7/9 expression in both fibroblasts and tenocytes. Furthermore, high circRNA-Ep400-containing exosome treatment promoted fibrosis, proliferation, and migration in both fibroblasts and tenocytes. Taken together, the results show that M2 macrophage-derived circRNA-Ep400-containing exosomes promote peritendinous fibrosis after TI via the miR-15b-5p/FGF-1/7/9 pathway, which suggests novel therapeutics for tendon injury treatment.

Abstract Background Long non-coding RNAs (lncRNAs) have been associated with non-small cell lung cancer (NSCLC), but the underlying molecular mechanisms of their specific roles in mediating aerobic glycolysis have been poorly explored. Methods Next-generation RNA sequencing assay was performed to identify the differentially expressed RNAs between NSCLC tissues with high 18F-fluorodeoxyglucose (FDG) uptake and their adjacent normal lung tissues. LINC01123 expression in NSCLC tissues was measured by real-time PCR and in situ hybridization (ISH) assay. The biological role of LINC01123 in cell growth and aerobic glycolysis capability was determined by performing functional experiments in vitro and in vivo. Further, the transcription of LINC01123 was explored by bioinformatics analysis, dual-luciferase reporter assay, and chromatin immunoprecipitation (ChIP) assay. RNA immunoprecipitation (RIP) and luciferase analyses were used to confirm the predicted competitive endogenous RNA (ceRNA) mechanisms between LINC01123 and c-Myc. Results Three hundred sixty-four differentially expressed genes were identified in RNA-seq assay, and LINC01123 was one of the most overexpressed lncRNAs. Further validation in expanded NSCLC cohorts confirmed that LINC01123 was upregulated in 92 paired NSCLC tissues and associated with poor survival. Functional assays showed that LINC01123 promoted NSCLC cell proliferation and aerobic glycolysis. Mechanistic investigations revealed that LINC01123 was a direct transcriptional target of c-Myc. Meanwhile, LINC01123 increased c-Myc mRNA expression by sponging miR-199a-5p. In addition, rescue experiments showed that LINC01123 functioned as an oncogene depending on miR-199a-5p and c-Myc. Conclusion Since LINC01123 is upregulated in NSCLC, correlates with prognosis, and controls proliferation and aerobic glycolysis by a positive feedback loop with c-Myc, it is expected to be a potential biomarker and therapeutic target for NSCLC.

The circular RNA RAPGEF5 (circRAPGEF5) is generated from five exons of the RAPGEF5 gene and abnormal expression in papillary thyroid cancer (PTC). However, whether circRAPGEF5 plays a role in PTC tumorigenesis remains unclear. The aim of the present study was to investigate the role of circRAPGEF5 in PTC. The results showed that circRAPGEF5 was upregulated in PTC tissues and cell lines. circRAPGEF5 knockdown inhibited cell proliferation, migration, and invasion in vitro; and circRAPGEF5 silencing downregulated fibroblast growth factor receptor 1 (FGFR1) expression by “sponging” miR-198, suppressing the aggressive biological behaviors of PTC. Luciferase reporter assays confirmed that circRAPGEF5 interacted with miR-198 and that miR-198 interacted with the 3′ UTR of FGFR1 to downregulate its expression. Xenograft experiments confirmed that circRAPGEF5 knockdown suppressed FGFR1-mediated tumor growth by promoting miR-198 expression. circRAPGEF5 acts as a tumor promoter via a novel circRAPGEF5/miR-198/FGFR1 axis, providing a potential biomarker and therapeutic target for the management of PTC. Keywords: circRNA RAPGEF5, papillary thyroid cancer, miR-198, FGFR1, sponging

Background: Lung cancer is among the most dangerous malignant tumors to human health. Lung adenocarcinoma (LUAD) accounts for about 40% of all lung cancers. Accumulating evidence suggests that the tumor microenvironment (TME) is a crucial regulator of carcinogenesis and therapeutic efficacy in LUAD. However, the impact of tumor microenvironment-related signatures (TMERSs) representing the TME characteristics on the prognosis and therapeutic outcome of LUAD patients remains to be further explored. Materials and methods: Gene expression files and clinical information of 1630 LUAD samples and 275 samples with immunotherapy information from different databases such as The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO) and Cancer Research Institute (CRI) iAtlas were downloaded and analyzed. Three hundred tumor microenvironment-related signatures (TMERS) based on a comprehensive collection of marker genes were quantified by single sample gene set enrichment analysis (ssGSEA), and then eight significant signatures were selected to construct the tumor microenvironment-related signature score (TMERSscore) by performing Least Absolute Shrinkage and Selection Operator (LASSO)-Cox analysis. Results: In this study, we constructed a TME-based prognostic stratification model for patients with LUAD and validated it in several external datasets. Furthermore, the TMERSscore was found to be positively correlated with tumor malignancy and a high TMERSscore predicted a poor prognosis. Moreover, the TMERSscore of responders treated with Immune Checkpoint Inhibitor (ICI) therapies was significantly lower than that of non-responders, and the TMERSscore was positively correlated with the tumor immune dysfunction and exclusion (TIDE) score, implying that a low TMERSscore predicts a better response to ICI treatment and may provide independent and incremental predictive value over current biomarkers. Conclusions: Overall, we constructed a TMERSscore that can be used for LUAD patient prognosis stratification as well as ICI therapeutic efficacy evaluation, supportive results from independent external validation sets showed its robustness and effectiveness.

Solasonine is a compound isolated from Solanum melongena that has anti-infection properties, and promotes neurogenesis. However, the use of solasonine for the treatment of hepatocellular carcinoma (HCC) has not yet been reported. So, the aim of this study was to assess the efficacy of solasonine for the treatment of HCC. The effects of solasonine were tested using the HCC cell lines HepG2 and HepRG. Metabolomics analysis was conducted to assess the effects of solasonine on tumor growth of nude mice xenografts using HepG2 cells. The data demonstrated that solasonine significantly suppressed proliferation of HepG2 and HepRG cells. A mouse xenograft model of HepG2 tumor formation confirmed that solasonine suppressed tumor volume and weight, and inhibited HCC cell migration and invasion, as determined with the Transwell and scratch wound assays. To further reveal the underlying regulatory mechanism, metabolomics analysis was performed. The results revealed the effects of solasonine on glutathione metabolism, including glutathione peroxidase 4 (GPX4) and glutathione synthetase (GSS). The glutathione-dependent lipid hydroperoxidase GPX4 prevents ferroptosis by converting lipid hydroperoxides into non-toxic lipid alcohols. Ferroptosis has previously been implicated in the cell death that underlies several degenerative conditions, and induction of ferroptosis by the inhibition of GPX4 has emerged as a therapeutic strategy to trigger cancer cell death. Solasonine increased lipid ROS levels in HepG2 cells by suppression of GPX4 and GSS. However, the use of a ferroptosis inhibitor reversed solasonine-induced ROS production and cell apoptosis. Taken together, these results demonstrate that solasonine promotes ferroptosis of HCC cells via GPX4-induced destruction of the glutathione redox system.

Acetaminophen (APAP) overdose is the main cause of acute liver failure. Apigenin (API) is a natural dietary flavonol with high antioxidant capacity. Herein, we investigated protection by API against APAP-induced liver injury in mice, and explored the potential mechanism. Cell viability assays and mice were used to evaluate the effects of API against APAP-induced liver injury. Western blotting, immunofluorescence staining, RT-PCR, and Transmission Electron Microscope were carried out to determine the signalling pathways affected by API. Analysis of mouse serum levels of alanine/aspartate aminotransferase (ALT/AST), malondialdehyde (MDA), liver myeloperoxidase (MPO) activity, glutathione (GSH), and reactive oxygen species (ROS) revealed that API (80 mg/kg) owned protective effect on APAP-induced liver injury. Meanwhile, API ameliorated the decreased cell viability in L-02 cells incubated by APAP with a dose dependent. Furthermore, API promoted SIRT1 expression and deacetylated p53. Western blotting showed that API promoted APAP-induced autophagy, activated the NRF2 pathway, and inhibited the transcriptional activation of nuclear p65 in the presence of APAP. Furthermore, SIRT1 inhibitor EX-527 reduced protection by API against APAP-induced hepatotoxicity. Molecular docking results indicate potential interaction between API and SIRT1. API prevents APAP-induced liver injury by regulating the SIRT1-p53 axis, thereby promoting APAP-induced autophagy and ameliorating APAP-induced inflammatory responses and oxidative stress injury.

Acetaminophen (APAP) overdose is a leading cause of drug-induced acute liver failure in clinical and hospital settings. Fisetin (FST) is a phenolic compound derived from natural products such as fruit and vegetables. Our research investigated the protective mechanisms of FST in APAP-induced hepatic injury in vitro and vivo. Assessment of mouse serum levels of alanine/aspartate aminotransferases (ALT/AST), liver myeloperoxidase (MPO) activity, malondialdehyde (MDA), glutathione (GSH), and reactive oxygen species (ROS) demonstrated the protective effects of FST toward APAP-induced liver injury. FST also reversed an APAP-induced decrease in mouse L-02 cell line viability. Our results also showed that FST significantly promoted APAP-induced autophagy and inhibited inflammasome activation both in vivo and in vitro. We also found that silencing ATG5, using si-ATG5, reduced the protective effects of FST against APAP-induced hepatotoxicity and reversed the effects on autophagy. Finally, we used the autophagy inhibitor, 3-methyladenine (3-MA) to validate the involvement of autophagy in FST against APAP-induced hepatotoxicity in vitro. We demonstrated that FST prevented APAP-induced hepatotoxicity by increasing ATG5 expression, thereby promoting autophagy and inhibiting inflammasome activation.

Adipose-derived stromal cells (ADSCs) have been considered as an attractive therapeutic tool. Accumulating evidence indicates that the healing effects of ADSCs are mainly related to paracrine action rather than transdifferentiation. Data show that the expression of miR-93-5p has a cardio-protective effect after acute myocardial infarction (AMI). To identify whether miR-93-5p-encapsulating exosomes that form ADSCs have a better cardio-protective effect, we investigated the inflammatory factors and miR-30d-5p expression in clinical levels. A rat model of AMI and an in vitro model of hypoxic H9c2 cells were established to study the protective mechanism of miR-93-5p in ischemia-induced cardiac injury. The results show that the expression of inflammatory cytokines and miR-93-5p were increased following AMI in both patients and animal models. Moreover, treatment with ADSC-derived miR-93-5p-containing exosomes has a greater protective effect on infarction-induced myocardial damage than simple exosome processing. Furthermore, in vitro experiments confirmed that the expression of miR-93-5p can significantly suppress hypoxia-induced autophagy and inflammatory cytokine expression by targeting Atg7 and Toll-like receptor 4 (TLR4), respectively, and was confirmed with Atg7 or TLR4 overexpression. The results also show that autophagy activation can promote inflammatory cytokine expression indirectly. Taken together, these results suggest that the miR-93-5p-enhanced ADSC-derived exosomes prevent cardiac injury by inhibiting autophagy and the inflammatory response.

Background/Aims: Recent studies have indicated that exosomes secreted from adipose-derived stem cells (ADSCs) have important effects in the treatment of ischemic injury. However, the treatment mechanism is unclear. This study aimed to investigate whether ADSC-derived exosomes enriched with microRNA (miR)-30d-5p have a protective effect on acute ischemic stroke (AIS). Methods: In the current study, inflammatory factors and miR-30d-5p expression were assessed in 70 subjects with AIS and 35 healthy controls. Exosomes were characterized by transmission electron microscopy and further examined using nanoparticle tracking analyses. A rat model of AIS and an in vitro model of oxygen- and glucose-deprived (OGD) primary microglia were established to study the protective mechanism of exosomes from miR-30d-5p-overexpressing ADSCs in ischemia-induced nerve injury. Results: The results showed that following AIS, the expression of inflammatory cytokines increased, while the anti-inflammatory cytokines IL-4, IL-10, and miR-30d-5p decreased both in patients and in animal models. Moreover, in vitro studies demonstrated that suppression of autophagy significantly reduced the OGD-induced inflammatory response. In addition, exosome treatment was more effective in suppressing the inflammatory response by reversing OGD-induced and autophagy-mediated microglial polarization to M1. Furthermore, in vivo studies showed that exosomes derived from ADSCs significantly decreased the cerebral injury area of infarction by suppressing autophagy and promoting M2 microglia/macrophage polarization. Conclusions: Our results suggest that miR-30d-5p-enhanced ADSC-derived exosomes prevent cerebral injury by inhibiting autophagy-mediated microglial polarization to M1.

Background/Aims: Recent studies have indicated that exosomes play an important role in adipose-derived stem cell (ADSC) transplant-mediated ischaemic heart disease therapy. However, the treatment effect is not obvious. The aim of this study is to investigate whether ADSC-derived exosomes enriched with microRNA (miR)-126 have a more protective effect on acute myocardial infarction (AMI). Methods: Exosomes were characterized by transmission electron microscopy, and the exosome particles were further examined using nanoparticle tracking analyses. A rat model of myocardial infarction and in vitro model of hypoxia-induced H9c2 myocardial cell injury were established to study the protective mechanism of exosomes from miR-126-overexpressing ADSCs. Results: The in vitro results showed that exosomes derived from miR-126-overexpressing ADSCs decreased H9c2 myocardial cell injury by reducing inflammation factor expression during hypoxia induction. The miR-126-enriched exosomes also decreased the expression of fibrosis-related proteins of H9c2 cells under hypoxic conditions. Matrigel® and Transwell® assays showed that miR-126-enriched exosomes significantly promoted microvascular generation and migration, respectively. In vivo studies confirmed that exosomes derived from ADSCs significantly decreased the myocardial injury area of infarction, especially after miR-126-enriched exosome treatment. Cardiac fibrosis and inflammatory cytokine expression were also decreased after treatment with miR-126-enriched exosomes. However, blood vessel formation was promoted in the infarction region of AMI rats. Conclusions: The results suggested that the expression of miR-126-enhanced ADSC-derived exosomes prevented myocardial damage by protecting myocardial cells from apoptosis, inflammation, fibrosis, and increased angiogenesis.

Isocitrate deyhdrogenase (IDH) is a reversible enzyme in the tricarboxylic acid cycle that catalyzes the NAD(P)(+)-dependent oxidative decarboxylation of isocitrate to α-ketoglutarate (αKG) and the NAD(P)H/CO2-dependent reductive carboxylation of αKG to isocitrate. The IDH gene from Streptococcus mutans was fused with the icd gene promoter from Escherichia coli to initiate its expression in the glutamate auxotrophic strain E. coli Δicd::kan(r) of which the icd gene has been replaced by kanamycin resistance gene. The expression of S. mutans IDH (SmIDH) may restore the wild-type phenotype of the icd-defective strain on minimal medium without glutamate. The molecular weight of SmIDH was estimated to be 70 kDa by gel filtration chromatography, suggesting a homodimeric structure. SmIDH was divalent cation-dependent and Mn(2+) was found to be the most effective cation. The optimal pH of SmIDH was 7.8 and the maximum activity was around 45°C. SmIDH was completely NAD(+) dependent and its apparent Km for NAD(+) was 137 μM. In order to evaluate the role of the putative phosphorylation site at Ser102 in catalysis, two "stably phosphorylated" mutants were constructed by converting Ser102 into Glu102 or Asp102 in SmIDH to mimick a constitutively phosphorylated state. Meanwhile, the functional roles of another four amino acids (threonine, glycine, alanine and tyrosine) containing variant size of side chains were investigated. The replacement of Asp102 or Glu102 totally inactivated the enzyme, while the S102T, S102G, S102A and S102Y mutants decreased the affinity to isocitrate and only retained 16.0%, 2.8%, 3.3% and 1.1% of the original activity, respectively. These results reveal that Ser102 plays important role in substrate binding and is required for the enzyme function. Also, Ser102 in SmIDH is a potential phosphorylation site, indicating that the ancient NAD-dependent IDHs might be the underlying origin of "phosphorylation mechanism" used by their bacterial NADP-dependent homologs.