Down-Regulating the Expression of miRNA-21 Inhibits the Glucose Metabolism of A549/DDP Cells and Promotes Cell Death Through the PI3K/AKT/mTOR/HIF-1α Pathway

LINC01224 promotes the Warburg effect in gastric cancer by activating the miR-486-5p/PI3K axis

The Warburg effect, a common feature of solid tumors, rewires the metabolism and promotes growth, survival, proliferation, and long-term maintenance in gastric cancer (GC). We performed in vitro and in vivo studies of the pathogenesis of GC to investigate the effects and mechanism of LINC01224 in this cancer. qRT-PCR was used to measure the expression of LINC01224 or miR-486-5p in GC cells, and the expression of LINC01224 in GC tissues by FISH (Fluorescence in situ hybridization) analysis was evaluated. Bioinformatics predicted the target gene of LINC01224, Western blotting was used to measure the protein expression of genes in the PI3K/AKT/mTOR/HIF-1α axis and Warburg effect in GC cells. The function of LINC01224 in GC cells was determined using measurements of EDU assay, colony formation, apoptosis, cell migration, and cell invasion. Glucose metabolism was evaluated using a glucose uptake assay and measurements of lactate. A tumor xenograft model was used to examine the effect of LINC01224 on GC growth in vivo. We found that upregulation of LINC01224 in GC cells activated the miR-486-5p/PI3K axis and promoted aerobic glycolysis, thereby increasing cell viability, proliferation, migration, invasion and anti-apoptosis. LINC01224 downregulation had the opposite effect. LINC01224 expression promoted the in vitro and in vivo pathogenesis of GC by promoting aerobic glycolysis. LINC01224 is a promising target in the treatment of GC.

In vitro and in vivo antineoplastic activities of solamargine in colorectal cancer through the suppression of PI3K/AKT pathway

PURPOSE

Previous research has demonstrated the efficacy of SM in inhibiting tumor growth in various cancer types. The objective of this study was to examine the antineoplastic effects and molecular mechanisms of Solamargine (SM) in colorectal cancer.

METHODS

Colorectal cancer (CRC) cells were treated with different concentrations of SM to evaluate the anticancer concentration for further experimental measurements. Additionally, the antitumor efficacy of SM was assessed in a subcutaneously implanted tumor model of colorectal cancer. RNA-seq and bioinformatics analyses were employed to identify differentially expressed genes (DEGs) and elucidate the underlying molecular mechanisms in LoVo cells. Subsequently, the specific mechanism of SM-mediated anti-tumor activities was analyzed by protein expression methods.

RESULTS

The results of in vitro assays demonstrated that SM exhibits significant inhibitory effects on cell proliferation, clone formation, and invasion, while also promoting apoptosis in SW48 and LoVo cells. In a mouse xenograft tumor model, intragastric administration of SM at doses of 5 or 10 mg/kg effectively suppressed tumor volume and weight, and induced cell apoptosis in vivo. SM treatment also down-regulated PCNA and Cyclin E protein expression, contributing to the regulation of apoptosis. Further analysis using RNA-seq, bioinformatics, and experimental measurements revealed that SM treatment upregulates PTEN expression, while significantly reducing the phosphorylation levels of Akt and mTOR in LoVo cells.

CONCLUSION

Our study provides further evidence to support the notion that SM primarily induces apoptosis in colorectal cancer cells through the inhibition of the PI3K/Akt signaling pathway. Additionally, our investigation demonstrated the favorable safety profile of SM in a mouse model of colorectal cancer, thereby suggesting its potential as a promising therapeutic approach for the management of CRC.

MicroRNAs in metabolism for precision treatment of lung cancer

The dysregulation of miRNAs in lung cancer has been extensively documented, with specific miRNAs acting as both tumor suppressors and oncogenes, depending on their target genes. Recent research has unveiled the regulatory roles of miRNAs in key metabolic pathways, such as glycolysis, the tricarboxylic acid cycle, fatty acid metabolism, and autophagy, which collectively contribute to the aberrant energy metabolism characteristic of cancer cells. Furthermore, miRNAs are increasingly recognized as critical modulators of the tumor microenvironment, impacting immune response and angiogenesis. This review embarks on a comprehensive journey into the world of miRNAs, unraveling their multifaceted roles, and more notably, their emerging significance in the context of cancer, with a particular focus on lung cancer. As we navigate this extensive terrain, we will explore the fascinating realm of miRNA-mediated metabolic rewiring, a phenomenon that plays a pivotal role in the progression of lung cancer and holds promise in the development of novel therapeutic strategies.

Long noncoding RNA TMPO-AS1 accelerates glycolysis by regulating the miR-1270/PKM2 axis in colorectal cancer

BACKGROUND

Long noncoding RNA thymopoietin-antisense RNA 1 (TMPO-AS1) is recognized as a participant in cancer progression. Nevertheless, its biological function in colorectal cancer remains obscure and needs further elucidation.

METHODS AND RESULTS

First, we discovered enriched TMPO-AS1 in the tumor tissues that were related to poor prognosis. TMPO-AS1 knockdown enhanced SW480 cell apoptosis but inhibited invasion, proliferation, migration, and glucose metabolism. Further, MiR-1270 is directly bound with TMPO-AS1. MiR-1270 mimics were confirmed to inhibit cell proliferation, invasion, and glucose metabolism in our study. Mechanistically, miR-1270 directly is bound with the 3' untranslated regions (3'UTR) of PKM2 to downregulate PKM2. MiR-1270 inhibitors reversed the TMPO-AS1 knockdown's effect on suppressing the tumor cell proliferation, invasion, and glycolysis, while the knockdown of PKM2 further inverted the function of miR-1270 inhibitors on the TMPO-AS1 knockdown.

CONCLUSIONS

This study illustrated that TMPO-AS1 advanced the development and the glycolysis of colorectal cancer by modulating the miR-1270/PKM2 axis, which provided a new insight into the colorectal cancer therapeutic strategy.

Detailed role of microRNA-mediated regulation of PI3K/AKT axis in human tumors

The regulation of signal transmission and biological processes, such as cell proliferation, apoptosis, metabolism, migration, and angiogenesis are greatly influenced by the PI3K/AKT signaling pathway. Highly conserved endogenous non-protein-coding RNAs known as microRNAs (miRNAs) have the ability to regulate gene expression by inhibiting mRNA translation or mRNA degradation. MiRNAs serve key role in PI3K/AKT pathway as upstream or downstream target, and aberrant activation of this pathway contributes to the development of cancers. A growing body of research shows that miRNAs can control the PI3K/AKT pathway to control the biological processes within cells. The expression of genes linked to cancers can be controlled by the miRNA/PI3K/AKT axis, which in turn controls the development of cancer. There is also a strong correlation between the expression of miRNAs linked to the PI3K/AKT pathway and numerous clinical traits. Moreover, PI3K/AKT pathway-associated miRNAs are potential biomarkers for cancer diagnosis, therapy, and prognostic evaluation. The role and clinical applications of the PI3K/AKT pathway and miRNA/PI3K/AKT axis in the emergence of cancers are reviewed in this article.

MicroRNA‑mediated regulation in lung adenocarcinoma: Signaling pathways and potential therapeutic implications (Review)

Lung adenocarcinoma (LUAD) poses a significant global health burden owing to its high incidence rate and unfavorable prognosis, driven by frequent recurrence and drug resistance. Understanding the biological mechanisms underlying LUAD is imperative to developing advanced therapeutic strategies. Recent research has highlighted the role of dysregulated microRNAs (miRNAs) in LUAD progression through diverse signaling pathways, including the Wnt and AKT pathways. Of particular interest is the novel pathological mechanism involving the interaction between competing endogenous RNAs (ceRNAs) and miRNAs. This review critically analyzed the impact of aberrant miRNA expression on LUAD development, shedding light on the associated signaling pathways. It also highlighted the emerging significance of ceRNA‑miRNA interactions in LUAD pathogenesis. Elucidating the intricate regulatory networks involving miRNAs and ceRNAs presents a promising avenue for the development of potential therapeutic interventions and diagnostic biomarkers in LUAD. Further research in this area is essential to advance precision medicine approaches and improve patient outcomes.

Composition of Conditioned Media from Radioresistant and Chemoresistant Cancer Cells Reveals miRNA and Other Secretory Factors Implicated in the Development of Resistance

Resistance to chemo- or radiotherapy is the main obstacle to consistent treatment outcomes in oncology patients. A deeper understanding of the mechanisms driving the development of resistance is required. This review focuses on secretory factors derived from chemo- and radioresistant cancer cells, cancer-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), and cancer stem cells (CSCs) that mediate the development of resistance in unexposed cells. The first line of evidence considers the experiments with conditioned media (CM) from chemo- and radioresistant cells, CAFs, MSCs, and CSCs that elevate resistance upon the ionizing radiation or anti-cancer drug exposure of previously untreated cells. The composition of CM revealed factors such as circular RNAs; interleukins; plasminogen activator inhibitor; and oncosome-shuttled lncRNAs, mRNAs, and miRNAs that aid in cellular communication and transmit signals inducing the chemo- and radioresistance of sensitive cancer cells. Data, demonstrating that radioresistant cancer cells become resistant to anti-neoplastic drug exposure and vice versa, are also discussed. The mechanisms driving the development of cross-resistance between chemotherapy and radiotherapy are highlighted. The secretion of resistance-mediating factors to intercellular fluid and blood brings attention to its diagnostic potential. Highly stable serum miRNA candidates were proposed by several studies as prognostic markers of radioresistance; however, clinical studies are needed to validate their utility. The ability to predict a treatment response with the help of the miRNA resistance status database will help with the selection of an effective therapeutic strategy. The possibility of miRNA-based therapy is currently being investigated with ongoing clinical studies, and such approaches can be used to alleviate resistance in oncology patients.

miR-383-5p serves as a tumor suppressor in bladder cancer by suppressing PI3K/AKT signaling pathway

BACKGROUND

MicroRNAs have been proven to be key molecules in human malignancy. However, to our knowledge, there is no study reporting miR-383-5p expression level and the role it plays in bladder cancer (BC).

METHODS

We identified miR-383-5p to be one of the tumor-suppressing genes through using data from The Cancer Genome Atlas (TCGA) and GEO database. We evaluate the expression and activity of miR-383-5p in both BC tissue and cell lines. The impacts of miR-383-5p on proliferative, migratory ability and apoptotic rate in BC cell were evaluated by utilizing CCK-8 kits, flow cytometry, and Transwell assays. qRT-PCR, western blot, and luciferase reporter assays have been adopted to investigate the underlying mechanisms. In vivo tumorigenicity testing was conducted to determine the impact of miR-383-5p on BC cellular proliferative capacity.

RESULTS

Reduced miR-383-5p expression has been determined in BC tissue than in normal bladder tissue. Furthermore, BC cell proliferative, migratory ability was inhibited while apoptosis enhanced in vitro and in vivo by miR-383-5p up-regulation. In vitro and in vivo, silencing miR-383-5p considerably improved the growth and invasive capacity of cell, while decreased the apoptotic rates of BC cells.

CONCLUSION

miR-383-5p plays its role as a tumor-suppressing gene by suppressing the PI3K/AKT signaling, hence preventing the development of BC.

Nur77 Serves as a Potential Prognostic Biomarker That Correlates with Immune Infiltration and May Act as a Good Target for Prostate adenocarcinoma

Prostate adenocarcinoma (PRAD) is the most frequent malignancy, and is the second leading cause of death due to cancer in men. Thus, new prognostic biomarkers and drug targets for PRAD are urgently needed. As we know, nuclear receptor Nur77 is important in cancer development and changes in the tumor microenvironment; whereas, the function of Nur77 in PRAD remains to be elucidated. The TCGA database was used to explore the Nur77 expression and its role in the prognosis of PRAD. It was shown that Nur77 was down regulated in PRAD, and low Nur77 expression was correlated with advanced clinical pathologic characteristics (high grade, histological type, age) and poor prognosis. Furthermore, key genes screening was examined by univariate Cox analysis and Kaplan-Meier survival. Additionally, Nur77 was closely related to immune infiltration and some anti-tumor immune functions. The differentially expressed genes (DEGs) were presented by protein-protein interaction (PPI) network analysis. Therefore, the expression level of Nur77 might help predict the survival of PRAD cases, which presents a new insight and a new target for the treatment of PRAD. In vitro experiments verified that natural product malayoside targeting Nur77 exhibited significant therapeutic effects on PRAD and largely induced cell apoptosis by up-regulating the expression of Nur77 and its mitochondrial localization. Taken together, Nur77 is a prognostic biomarker for patients with PRAD, which may refresh the profound understanding of PRAD individualized treatment.

Overcoming Basal Autophagy, Kangai Injection Enhances Cisplatin Cytotoxicity by Regulating FOXO3a-Dependent Autophagic Cell Death and Apoptosis in Human Lung Adenocarcinoma A549/DDP Cells

Cisplatin resistance is one of the major obstacles in the treatment of nonsmall cell lung cancer (NSCLC). Kangai injection (KAI), a Chinese herbal medicine, has been used in tumors as adjuvant treatment, but its exact antitumor mechanism is still unclear. In this study, we first demonstrated that cisplatin-resistant A549/DDP cells showed a higher level of basal autophagy in response to cisplatin treatment with increasing autophagic protein expression levels of Beclin 1, p62, and LC3 compared to cisplatin-sensitive A549/DDP cells; then, we assessed the antitumor effect of KAI in cisplatin-resistant lung adenocarcinoma A549/DDP cells. Our results showed that KAI exhibited direct cytotoxic and chemosensitizing effects in A549/DDP cells. Combining KAI with cisplatin promoted A549/DDP cell apoptosis, which was confirmed by cell cycle arrest, condensed nuclear chromatin, annexin V fluorescein isothiocyanate/propidium iodide (Annexin V-FITC/PI) staining, and apoptosis-related protein expression. In addition, combining KAI with cisplatin induced autophagic cell death in A549/DDP cells with a high level of basal autophagy, as indicated by an increase in LC3 spot count, an accumulation of Beclin 1 and LC3 II, and reduced p62 protein expression. We also found that the apoptosis and autophagic cell death induced by cotreatment of KAI and cisplatin in A549/DDP cells were FOXO3a-dependent as indicated by decreased p-FOXO3a expression and increased FOXO3a nuclear localization, respectively. Furthermore, the FOXO3a gene knockdown assay further confirmed that KAI enhanced cisplatin cytotoxicity in A549/DDP cells with a high level of basal autophagy by inducing apoptosis and autophagic cell death in a FOXO3a-dependent manner. These findings suggest that the combination of KAI and cisplatin might support the potential clinical treatment as a novel strategy to overcome cisplatin resistance.

Role of HIF-1α/ERRα in Enhancing Cancer Cell Metabolism and Promoting Resistance of Endometrial Cancer Cells to Pyroptosis

Oxygen is critical to energy metabolism, and tumors are often characterized by a hypoxic microenvironment. Owing to the high metabolic energy demand of malignant tumor cells, their survival is promoted by metabolic reprogramming in the hypoxic microenvironment, which can confer tumor cell resistance to pyroptosis. Pyroptosis resistance can inhibit anti-tumor immunity and promote the development of malignant tumors. Hypoxia inducible factor-1α (HIF-1α) is a key regulator of metabolic reprogramming in tumor cells, and estrogen-related receptor α (ERRα) plays a key role in regulating cellular energy metabolism. Therefore, the close interaction between HIF-1α and ERRα influences the metabolic and functional changes in cancer cells. In this review, we summarize the reprogramming of tumor metabolism involving HIF-1α/ERRα. We review our understanding of the role of HIF-1α/ERRα in promoting tumor growth adaptation and pyroptosis resistance, emphasize its key role in energy homeostasis, and explore the regulation of HIF-1α/ERRα in preventing and/or treating endometrial carcinoma patients. This review provides a new perspective for the study of the molecular mechanisms of metabolic changes in tumor progression.

Deferoxamine Counteracts Cisplatin Resistance in A549 Lung Adenocarcinoma Cells by Increasing Vulnerability to Glutamine Deprivation-Induced Cell Death

Glutamine, like glucose, is a major nutrient consumed by cancer cells, yet these cells undergo glutamine starvation in the cores of tumors, forcing them to evolve adaptive metabolic responses. Pharmacologically targeting glutamine metabolism or withdrawal has been exploited for therapeutic purposes, but does not always induce cancer cell death. The mechanism by which cancer cells adapt to resist glutamine starvation in cisplatin-resistant non-small-cell lung cancer (NSCLC) also remains uncertain. Here, we report the potential metabolic vulnerabilities of A549/DDP (drug-resistant human lung adenocarcinoma cell lines) cells, which were more easily killed by the iron chelator deferoxamine (DFO) during glutamine deprivation than their parental cisplatin-sensitive A549 cells. We demonstrate that phenotype resistance to cisplatin is accompanied by adaptive responses during glutamine deprivation partly via higher levels of autophagic activity and apoptosis resistance characteristics. Moreover, this adaptation could be explained by sustained glucose instead of glutamine-dominant complex II-dependent oxidative phosphorylation (OXPHOS). Further investigation revealed that cisplatin-resistant cells sustain OXPHOS partly via iron metabolism reprogramming during glutamine deprivation. This reprogramming might be responsible for mitochondrial iron-sulfur [Fe-S] cluster biogenesis, which has become an “Achilles’ heel,” rendering cancer cells vulnerable to DFO-induced autophagic cell death and apoptosis through c-Jun N-terminal kinase (JNK) signaling. Finally, in vivo studies using xenograft mouse models also confirmed the growth-slowing effect of DFO. In summary, we have elucidated the adaptive responses of cisplatin-resistant NSCLC cells, which balanced stability and plasticity to overcome metabolic reprogramming and permitted them to survive under stress induced by chemotherapy or glutamine starvation. In addition, for the first time, we show that suppressing the growth of cisplatin-resistant NSCLC cells via iron chelator-induced autophagic cell death and apoptosis was possible with DFO treatment. These findings provide a solid basis for targeting mitochondria iron metabolism in cisplatin-resistant NSCLC for therapeutic purposes, and it is plausible to consider that DFO facilitates in the improvement of treatment responses in cisplatin-resistant NSCLC patients.

Dihydroartemisinin and Artesunate Inhibit Aerobic Glycolysis via Suppressing c-Myc Signaling in non-small Cell Lung Cancer

Non-small cell lung cancer (NSCLC) cells exhibit aberrant metabolism characterized by high glycolysis even in the presence of abundant oxygen. Inhibition of aerobic glycolysis remains challenging when identifying potential cancer-specific inhibitors while maintaining or even boosting the anti-cancer immunity. Artemisinin derivatives DHA and AS have shown excellent anti-tumor and immunoenhancing roles in numerous malignancies, but the molecular mechanism of DHA and AS in regulating cancer glucose metabolism is largely unknown. In this study, we proved that DHA and AS inhibit NSCLC growth via prohibiting cancer cell aerobic glycolysis through ERK/c-Myc pathway. First, we proved that DHA and AS have comparable anti-cancer growth roles in both NSCLC cell lines and mouse Lewis Lung Cancer model. Then, our data clearly showed that DHA and AS dose- and time-dependently reduce the uptake of glucose, the production of ATP, and the secretion of lactate, the expression of glucose transporter GLUT1 and two key glycolysis-related enzymes hexokinase and lactate dehydrogenase, as well as the level of c-Myc. Finally, we generated c-Myc^high stable-expressing NSCLC cell line and treated it with DHA or AS, respectively. Our data clearly showed that c-Myc overexpression can partially reverse the glycolysis-repressing role of DHA and AS which strongly supported our proposal that AS and DHA suppress aerobic glycolysis in a c-Myc-dependent manner in NSCLC cells. This study extends our knowledge of artemisinin derivatives in regulating tumor glucose metabolism and provides potential strategy in the therapy of lung cancer.