PRDX2 removal inhibits the cell cycle and autophagy in colorectal cancer cells

Natural products modulating MAPK for CRC treatment: a promising strategy

Colorectal cancer (CRC) is a common malignant tumor of the digestive system, and the pathogenic mechanism is still unclear, mostly related to genetics, immunity, inflammation, and abnormal activation of tumor-related signaling pathways. MAPK belongs to the Ser/Thr kinase family, which plays an important role in complex cellular programs such as the regulation of cell proliferation, differentiation, apoptosis, angiogenesis, and tumor metastasis. Increasing evidence supports that MAPK activation is highly correlated with the risk of CRC. Targeting MAPK may be a therapeutic strategy, and natural products show great therapeutic potential in regulating MAPK-related proteins. In this paper, we searched PubMed, Web of Science and CNKI databases with keywords "colorectal cancer, natural products, MAPK pathway, ERK, P38, JNK" for relevant studies in the last 14 years from 2010 to 2024. This work retrieved 47 studies, aiming to provide new therapeutic strategies for CRC patients and lay the foundation for new drug development.

PRDX2 induces tumor immune evasion by modulating the HDAC3-Galectin-9 axis in lung adenocarcinoma cells

BACKGROUND

PRDX2 is significantly expressed in various cancers and is associated with the proliferation of tumor cells. Nonetheless, the precise mechanism of PRDX2 in tumor immunity remains incompletely understood. This study aims to investigate the impact of PRDX2, which is highly expressed in lung adenocarcinoma, on T cells in the tumor immune microenvironment, and its immune action target to promote the immune escape of lung cancer cells, to provide a theoretical basis for lung adenocarcinoma treatment with PRDX2 as the target.

METHODS

Mouse animal models to verify the effect of Conoidin A treatment on tumor growth and T cell infiltration. Flow cytometry and Western blot verified tumor cell apoptosis in the in vitro co-culture system as well as granzyme B and perforin expression in T cells. RNA-Seq was used to obtain the downstream immune molecule. si-RNA knockdown of Galectin-9 was co-cultured with T cells in vitro. Immunofluorescence and Western blot verified that PRDX2 regulates Galectin-9 expression through HDAC3.

RESULTS

PRDX2 expression was negatively correlated with CD8+ T cell expression in LUAD patients. Inhibition of PRDX2 significantly enhanced T-cell killing of LUAD cells and reduced tumor load in both in vitro and in vivo models. Mechanistically, Conoidin A or shRNA_PRDX2 decreased Galectin-9 expression by down-regulating the phosphorylation of HDAC3, consequently enhancing the infiltration and function of CD8+ T cells.

CONCLUSIONS

This study reveals the role of the PRDX2/HDAC3/Galectin-9 axis in LUAD immune escape and indicates Galectin-9 as a promising target for immunotherapy.

Polysaccharides targeting autophagy to alleviate metabolic syndrome

Metabolic syndrome is a prevalent non-communicable disease characterized by central obesity, insulin resistance, hypertension, hyperglycemia, and hyperlipidemia. Epidemiological statistics indicate that one-third of the world's population is affected by metabolic syndrome. Unfortunately, owing to complicated pathogenesis and limited pharmacological options, the growing prevalence of metabolic syndrome threatens human health worldwide. Autophagy is an intracellular degradation mechanism that involves the degradation of unfolded or aggregated proteins and damaged cellular organelles, thereby maintaining metabolic homeostasis. Increasing evidence indicates that dysfunctional autophagy is closely associated with the development of metabolic syndrome, making it an attractive therapeutic target. Furthermore, a growing number of plant-derived polysaccharides have been shown to regulate autophagy, thereby alleviating metabolic syndrome, such as Astragalus polysaccharides, Laminaria japonica polysaccharides, Ganoderma lucidum polysaccharides and Lycium barbarum polysaccharides. In this review, we summarize recent advances in the discovery of autophagy modulators of plant polysaccharides for the treatment of metabolic syndrome, with the aim of providing precursor compounds for the development of new therapeutic agents. Additionally, we look forward to seeing more diseases being treated with plant polysaccharides by regulating autophagy, as well as the discovery of more intricate mechanisms that govern autophagy.

Knockdown of PRDX2 Inhibits the Proliferation, Growth, Migration, Invasion, and MMP9 Activity of Ewing's Sarcoma Cells Cultured In Vitro

BACKGROUND

Ewing's sarcoma (ES) is the second most common malignant primary bone tumor in children and adolescents. Peroxiredoxin 2 (PRDX2) is an antioxidant enzyme.

AIMS

Here, we investigated the role and mechanism of PRDX2 in the development of ES.

METHODS AND RESULTS

PRDX2 expression was knocked down in A673 and RDES cells by specific siRNA interference (si-PRDX2). Knockdown of PRDX2 strongly inhibited the proliferation, growth, migration, invasion, and MMP9 activity and induces apoptosis of A673 and RDES cells. si-PRDX2 significantly inhibited the phosphorylation of Akt and the expression of cyclin D1. The transcription factor that might regulate PRDX2 transcription was predicted with the JASPAR and UCSC databases, and analyzed using dual-luciferase and Chromatin co-immunoprecipitation experiments. SNAI1 could activate the transcription of PRDX2 by binding to predicted promoter binding site.

CONCLUSION

PRDX2 may be a potential therapeutic target for ES.

Peroxiredoxin 1 regulates crosstalk between pyroptosis and autophagy in oral squamous cell carcinoma leading to a potential pro-survival

Peroxiredoxin 1 (Prdx1), a vital antioxidant enzyme, has been proven to play an important role in the occurrence and development of cancers, but its effects on oral squamous cell carcinoma (OSCC) remain unclear. Here, we performed bioinformatics analysis and immunohistochemical (IHC) staining to confirm that Prdx1 was higher in OSCC tissues than in normal tissues. Consistently, RT-PCR and Western blot showed elevated Prdx1 expression in OSCC cell lines compared to human oral keratinocytes (HOK), which could be knockdown by small interfering RNA (siRNA) and Lentiviral vector delivery of short hairpin RNA (shRNA). Prdx1 silencing significantly blocked OSCC cell proliferation and metastasis, as evidenced by the CCK8, colony formation, in vivo tumorigenesis experiment, wound healing, transwell assays, and changes in migration-related factors. siPrdx1 transfection increased intracellular reactive oxygen species (ROS) levels and provoked pyroptosis, proved by the upregulation of pyroptotic factors and LDH release. Prdx1 silencing ROS-independently blocked autophagy. Mature autophagosome failed to form in the siPrdx1 group. Up-regulated autophagy limited pyroptosis triggered by Prdx1 deficiency, and down-regulated pyroptosis partly reversed siPrdx1-induced autophagy defect. Collectively, Prdx1 regulated pyroptosis in a ROS-dependent way and modulated autophagy in a ROS-independent way, involving the crosstalk between pyroptosis and autophagy.

Sulforaphene Inhibits Periodontitis through Regulating Macrophage Polarization via Upregulating Dendritic Cell Immunoreceptor

Periodontitis is one of the most prevalent chronic inflammatory diseases that may eventually lead to the loss of teeth. Macrophage polarization plays an important role in the development of periodontitis, and several naturally occurring food compounds have recently been reported to regulate macrophage polarization. In this study, we aimed to investigate the therapeutic potential of sulforaphene (SFE) in macrophage polarization and its impact on periodontitis. Through in vitro and in vivo experiments, our study demonstrated that SFE effectively inhibits M1 polarization while promoting M2 polarization, ultimately leading to the suppression of periodontitis. Transcriptome sequencing showed that SFE significantly upregulated the expression of dendritic cell immunoreceptor (DCIR, also known as CLEC4A2). We further validated the crucial role of DCIR in macrophage polarization through knockdown and overexpression experiments and demonstrated that SFE regulates macrophage polarization by upregulating DCIR expression. In summary, the results of this study suggest that SFE can regulate macrophage polarization and inhibit periodontitis. Moreover, this research identified DCIR (dendritic cell immunoreceptor) as a potential novel target for regulating macrophage polarization. These findings provide new insights into the treatment of periodontitis and other immune-related diseases.

HSPA8 regulates anti-bacterial autophagy through liquid-liquid phase separation

HSPA8 (heat shock protein family A (Hsp70) member 8) plays a significant role in the autophagic degradation of proteins, however, its effect on protein stabilization and anti-bacterial autophagy remains unknown. Here, it is discovered that HSPA8, as a binding partner of RHOB and BECN1, induce autophagy for intracellular bacteria clearance. Using its NBD and LID domains, HSPA8 physically binds to RHOB residues 1-42 and 89-118 as well as to BECN1 ECD domain, preventing RHOB and BECN1 degradation. Intriguingly, HSPA8 contains predicted intrinsically disordered regions (IDRs), and drives liquid-liquid phase separation (LLPS) to concentrate RHOB and BECN1 into HSPA8-formed liquid-phase droplets, resulting in improved RHOB and BECN1 interactions. Our study reveals a novel role and mechanism of HSPA8 in modulating anti-bacterial autophagy, and highlights the effect of LLPS-related HSPA8-RHOB-BECN1 complex on enhancing protein interaction and stabilization, which improves the understanding of autophagy-mediated defense against bacteria.

Negative pressure wound therapy promotes wound healing of diabetic foot ulcers by up-regulating PRDX2 in wound margin tissue

To understand the changes in the peroxiredoxin-2 (PRDX2) expression level in the wound margin tissue (T-PRDX2) of patients with diabetic foot ulcer (DFU) before and after negative pressure wound therapy (NPWT). Additionally, the study aimed to explore the association between PRDX2 expression and the treatment outcome of DFUs to provide a new theoretical basis for revealing the mechanism of NPWT promoting the healing of DFUs. Fifty-six type 2 diabetes patients with foot ulcers undergoing NPWT (the DFU group) and 28 patients with chronic lower limb skin ulcers with normal glucose tolerance undergoing NPWT (the skin ulcer control [SUC] group) were included in the study. T-PRDX2 was detected using Western blotting, and the superoxide dismutase (SOD) activity and the malondialdehyde (MDA) and glutathione (GSH) levels were detected using a biochemical method. In addition, in vitro experiments were conducted to determine the effect of PRDX2 expression on normal human dermal fibroblast (NHDF) proliferation, migration, and apoptosis. Before NPWT, the DFU group exhibited a significantly lower T-PRDX2 expression level compared with the SUC group. After one week of NPWT, the T-PRDX2 expression level, SOD activity, and GSH content in the wound margin tissues of the DFU and SUC groups significantly increased compared with the before NPWT levels. Conversely, the inflammatory indicators (white blood cell, neutrophil percentage, C-reactive protein, and procalcitonin) and MDA content were significantly lower than the before NPWT levels. The expression changes of T-PRDX2 before and after NPWT in the DFU and SUC groups were positively correlated with the 4-week wound healing rate. In vitro experiments demonstrated that PRDX2 could alleviate the oxidative stress in NHDFs, thereby promoting their proliferation and migration, while reducing cell apoptosis. NPWT promotes DFU healing by increasing T-PRDX2, and changes in the T-PRDX2 might be associated with the therapeutic effect of NPWT.

Prognostic and biological function value of OSBPL3 in colorectal cancer analyzed by multi-omic data analysis

BACKGROUND

Colorectal cancer (CRC) is one of the most common malignancies in the world. This study proposes to reveal prognostic biomarkers for the prognosis and treatment of CRC patients.

METHODS

Differential analysis of OSBPL3 was performed in pan-cancer, and the correlation between clinical stage and OSBPL3 was analyzed. Multiple omics analysis was used to compare the relationship between survival of patients and copy number variation, single nucleotide variant, and methylation status. Survival differences between high and low OSBPL3 expression groups were analyzed. Differentially expressed genes (DEGs) between high and low OSBPL3 expression groups were obtained, and functional enrichment analysis was implemented. Correlations between immune cells and OSBPL3 was analyzed. Drug sensitivity between the two OSBPL3 expression groups was compared. Moreover, the expression of OSBPL3 was verified by immunohistochemistry and real-time quantitative PCR.

RESULTS

OSBPL3 was differentially expressed in 13 tumors and had some correlations with T and N stages. OSBPL3 expression was regulated by methylation and higher OSBPL3 expression was associated with poorer prognosis in CRC. 128 DEGs were obtained and they were mainly involved in signaling receptor activator activity, aspartate and glutamate metabolism. T cell gamma delta and T cell follicular helper were significantly different in the high and low OSBPL3 expression groups. Moreover, OSBPL3 showed negative correlations with multiple drugs. OSBPL3 was significantly upregulated in CRC samples compared to normal samples.

CONCLUSIONS

A comprehensive analysis demonstrated that OSBPL3 had potential prognostic value, and guiding significance for CRC chemotherapeutic.

New insights into the roles of peroxiredoxins in cancer

Oxidative stress is one of the hallmarks of cancer. Tumorigenesis and progression are accompanied by elevated reactive oxygen species (ROS) levels and adaptive elevation of antioxidant expression levels. Peroxiredoxins (PRDXs) are among the most important antioxidants and are widely distributed in a variety of cancers. PRDXs are involved in the regulation of a variety of tumor cell phenotypes, such as invasion, migration, epithelial-mesenchymal transition (EMT) and stemness. PRDXs are also associated with tumor cell resistance to cell death, such as apoptosis and ferroptosis. In addition, PRDXs are involved in the transduction of hypoxic signals in the TME and in the regulation of the function of other cellular components of the TME, such as cancer-associated fibroblasts (CAFs), natural killer (NK) cells and macrophages. This implies that PRDXs are promising targets for cancer treatment. Of course, further studies are needed to realize the clinical application of targeting PRDXs. In this review, we highlight the role of PRDXs in cancer, summarizing the basic features of PRDXs, their association with tumorigenesis, their expression and function in cancer, and their relationship with cancer therapeutic resistance.

Integrative single-cell RNA and ATAC sequencing reveals that the FOXO1-PRDX2-TNF axis regulates tendinopathy

Introduction

Tendinopathy, the most common form of chronic tendon disorder, leads to persistent tendon pain and loss of function. Profiling the heterogeneous cellular composition in the tendon microenvironment helps to elucidate rational molecular mechanisms of tendinopathy.

Methods and results

In this study, through a multi-modal analysis, a single-cell RNA- and ATAC-seq integrated tendinopathy landscape was generated for the first time. We found that a specific cell subpopulation with low PRDX2 expression exhibited a higher level of inflammation, lower proliferation and migration ability, which not only promoted tendon injury but also led to microenvironment deterioration. Mechanistically, a motif enrichment analysis of chromatin accessibility showed that FOXO1 was an upstream regulator of PRDX2 transcription, and we confirmed that functional blockade of FOXO1 activity induced PRDX2 silencing. The TNF signaling pathway was significantly activated in the PRDX2-low group, and TNF inhibition effectively restored diseased cell degradation.

Discussion

We revealed an essential role of diseased cells in tendinopathy and proposed the FOXO1-PRDX2-TNF axis is a potential regulatory mechanism for the treatment of tendinopathy.

The Role of Peroxiredoxins in Cancer Development

Peroxiredoxins (Prxs) are antioxidant enzymes with ubiquitous expression in human tissues. Prxs are expressed in archaea, bacteria, and eukaryota, often in multiple isoforms. Because of their abundant expression in different cellular organelles and extraordinary sensitivity to H2O2, Prxs are among the first defenses against oxidative stress. Prxs undergo reversible oxidation to disulfides, and some family members perform chaperone or phospholipase functions upon further oxidation. Prxs are upregulated in cancer cells. Research has suggested that Prxs can function as tumor promoters in various cancers. The major objective of this review is to summarize novel findings regarding the roles of Prxs in common cancer types. Prxs have been shown to influence differentiation of inflammatory cells and fibroblasts, remodeling of extracellular matrix, and regulation of stemness. Since aggressive cancer cells have higher intracellular levels of ROS that they can utilize to proliferate and metastasize compared to normal cells, it is critical that we understand the regulation and functions of primary antioxidants such as Prxs. These small but mighty proteins could prove to be key for improving cancer therapeutics and patient survival.

miRNAs Participate in the Regulation of Oxidative Stress-Related Gene Expression in Endometrioid Endometrial Cancer

Reactive oxygen species are formed as by-products of normal cell metabolism. They are needed to maintain cell homeostasis and signaling, which is possible due to defense systems. Disruption of this balance leads to oxidative stress that can induce cancer. Redox regulation by miRNAs may be a potential therapeutic target. The aim of the study was to assess the activity of genes associated with oxidative stress in endometrial cancer and to determine their relationship with miRNAs. The study included 45 patients with endometrioid endometrial cancer and 45 without neoplastic changes. The expression profile of genes associated with oxidative stress was determined with mRNA microarrays, RT-qPCR and ELISA. The miRNA prediction was performed based on the miRNA microarray experiment and the mirDB tool. PRDX2 and AQP1 showed overexpression that was probably not related to miRNA activity. A high level of PKD2 may be the result of a decrease in the activity of miR-195-3p, miR-20a, miR-134. A SOD3 level reduction can be caused by miR-328, miR-363. In addition, miR-363 can also regulate KLF2 expression. In the course of endometrial cancer, the phenomenon of oxidative stress is observed, the regulation of which may be influenced by miRNAs.

Deleted in lymphocytic leukemia 2 induces retinoic acid receptor beta promoter methylation and mitogen activated kinase-like protein activation to enhance viability and mobility of colorectal cancer cells

Abnormal expression of long non-coding RNAs (lncRNAs) is frequently linked to the pathogenesis of colorectal cancer (CRC). This work explored the function of lncRNA deleted in lymphocytic leukemia 2 (DLEU2) in CRC and the epigenetic mechanism. Candidate oncogenes in CRC were predicted using a GSE146587 dataset. DLEU2 was highly expressed in CRC according to the bioinformatic analysis and its high expression was detected in CRC cells compared to the normal colon epithelial cells (FHC). Downregulation of DLEU2 in CRC SW480 and HT29 cells suppressed viability, migration, invasiveness, and resistance to apoptosis of cells. The mRNA microarray analysis was performed to explore the key molecules mediated by DLEU2. Retinoic acid receptor beta (RARB) expression was elevated in cells after DLEU2 downregulation. The promoter methylation of RARB was enhanced in CRC cells compared to normal FHC cells. DLEU2 induced promoter methylation of RARB to downregulate its expression. Further silencing of RARB restored proliferation and invasiveness of cells blocked by sh-DLEU2. Upregulation of DLEU2 activated the mitogen activated kinase-like protein (MAPK) signaling pathway to trigger CRC progression. In conclusion, this study demonstrates that DLEU2 enhances viability and mobility of CRC cells by inducing RARB promoter methylation and activating the MAPK signaling pathway.

Targeting autophagy in prostate cancer: preclinical and clinical evidence for therapeutic response

Prostate cancer is a leading cause of death worldwide and new estimates revealed prostate cancer as the leading cause of death in men in 2021. Therefore, new strategies are pertinent in the treatment of this malignant disease. Macroautophagy/autophagy is a “self-degradation” mechanism capable of facilitating the turnover of long-lived and toxic macromolecules and organelles. Recently, attention has been drawn towards the role of autophagy in cancer and how its modulation provides effective cancer therapy. In the present review, we provide a mechanistic discussion of autophagy in prostate cancer. Autophagy can promote/inhibit proliferation and survival of prostate cancer cells. Besides, metastasis of prostate cancer cells is affected (via induction and inhibition) by autophagy. Autophagy can affect the response of prostate cancer cells to therapy such as chemotherapy and radiotherapy, given the close association between autophagy and apoptosis. Increasing evidence has demonstrated that upstream mediators such as AMPK, non-coding RNAs, KLF5, MTOR and others regulate autophagy in prostate cancer. Anti-tumor compounds, for instance phytochemicals, dually inhibit or induce autophagy in prostate cancer therapy. For improving prostate cancer therapy, nanotherapeutics such as chitosan nanoparticles have been developed. With respect to the context-dependent role of autophagy in prostate cancer, genetic tools such as siRNA and CRISPR-Cas9 can be utilized for targeting autophagic genes. Finally, these findings can be translated into preclinical and clinical studies to improve survival and prognosis of prostate cancer patients.

• Prostate cancer is among the leading causes of death in men where targeting autophagy is of importance in treatment;

• Autophagy governs proliferation and metastasis capacity of prostate cancer cells;

• Autophagy modulation is of interest in improving the therapeutic response of prostate cancer cells;

• Molecular pathways, especially involving non-coding RNAs, regulate autophagy in prostate cancer;

• Autophagy possesses both diagnostic and prognostic roles in prostate cancer, with promises for clinical application.

Quantitative proteomic analysis of cervical cancer based on TMT-labeled quantitative proteomics

Cervical cancer is the second most common gynecological malignancy, which immensely threatens the well-being of women. However, the pathogenesis of cervical cancer is still unclear. Using tandem mass tags-labeled quantitative proteomic technology and bioinformatics tools, we analyzed the exfoliated cervical cells from the normal and cervical cancer groups to establish a cancer-specific protein profile, thereby identifying key proteins related to cervical oncogenesis. When compared with the normal group, a total of 351 differentially expressed proteins were identified in the cervical cancer group, including 247 up-regulated and 104 down-regulated proteins. Gene ontology function annotation revealed that the differentially expressed proteins were mainly involved in the single-multicellular organism process, multicellular organismal process, and negative regulation of biological process. These proteins were discerned to play a role in the extracellular membrane-bounded organelle, exosome of cell components, protein binding, structural molecule activity, and enzyme binding of molecular functions. The results of Kyoto Encyclopedia of Genes and Genomes signaling pathway enrichment proved that these differentially expressed proteins were mainly involved in PI3K - Akt, ECM-receptor interaction, complement and coagulation cascades, and other signaling pathways. Particularly, peroxiredoxin-2 may be involved in cervical tumor oncogenesis through inhibition of apoptosis signaling. SIGNIFICANCE: In this study, we determined that the proteins of the cervical cancer group exhibited qualitative and quantitative changes, and a total of 351 differentially expressed proteins were identified. The functions and signaling pathways of these differentially expressed proteins have laid a theoretical foundation for elucidating the molecular mechanism of cervical cancer.

CircDIDO1 inhibits gastric cancer progression by encoding a novel DIDO1-529aa protein and regulating PRDX2 protein stability

BACKGROUND

Circular RNAs (circRNAs) play important roles in cancer development and progression. The purpose of this study is to identify aberrantly expressed circRNAs in gastric cancer (GC), unravel their roles in GC progression, and provide new targets for GC diagnosis and therapy.

METHODS

Bioinformatic analyses were performed to identify the aberrantly expression of hsa_circ_0061137 (termed as circDIDO1) in GC. Gain- and loss-of-function studies were performed to examine the biological roles of circDIDO1 in GC progression. Tagged RNA affinity purification, mass spectrometry, immunofluorescence, co-immunoprecipitation, and Western blot were used to identify circRNA-interacting and circRNA-encoded proteins. RNA sequencing, qRT-PCR, and Western blot were performed to analyze circRNA-regulated downstream target genes and signaling pathways. Mouse tumor models were used to analyze the effects of circDIDO1 on GC growth and metastasis.

RESULTS

CircDIDO1 was transcribed from human DIDO1 (death-inducer obliterator 1) gene and formed by back-splicing of exons 2-6 of the linear transcript. circDIDO1 was down-regulated in GC tissues and its low levels were associated with larger tumor size, distal metastasis, and poor prognosis. CircDIDO1 overexpression inhibited while knockdown promoted GC cell proliferation, migration and invasion. CircDIDO1 overexpression suppressed GC growth and metastasis in mouse tumor models. Mechanistically, circDIDO1 encoded a novel 529aa protein that directly interacted with poly ADP-ribose polymerase 1 (PARP1) and inhibited its activity. CircDIDO1 also specifically bound to peroxiredoxin 2 (PRDX2) and promoted RBX1-mediated ubiquitination and degradation of PRDX2, which led to the inactivation of its downstream signaling pathways.

CONCLUSIONS

CircDIDO1 is a new circRNA that has tumor suppressor function in GC and it may serve as a potential prognostic biomarker and therapeutic target for GC.

Therapeutic potential of AMPK signaling targeting in lung cancer: Advances, challenges and future prospects

Lung cancer (LC) is a leading cause of death worldwide with high mortality and morbidity. A wide variety of risk factors are considered for LC development such as smoking, air pollution and family history. It appears that genetic and epigenetic factors are also potential players in LC development and progression. AMP-activated protein kinase (AMPK) is a signaling pathway with vital function in inducing energy balance and homeostasis. An increase in AMP:ATP and ADP:ATP ratio leads to activation of AMPK signaling by upstream mediators such as LKB1 and CamKK. Dysregulation of AMPK signaling is a common finding in different cancers, particularly LC. AMPK activation can significantly enhance LC metastasis via EMT induction. Upstream mediators such as PLAG1, IMPAD1, and TUFM can regulate AMPK-mediated metastasis. AMPK activation can promote proliferation and survival of LC cells via glycolysis induction. In suppressing LC progression, anti-tumor compounds including metformin, ginsenosides, casticin and duloxetine dually induce/inhibit AMPK signaling. This is due to double-edged sword role of AMPK signaling in LC cells. Furthermore, AMPK signaling can regulate response of LC cells to chemotherapy and radiotherapy that are discussed in the current review.

Nucleoredoxin Knockdown in SH-SY5Y Cells Promotes Cell Renewal

Nucleoredoxin (NXN) is a redox regulator of Disheveled and thereby of WNT signaling. Deficiency in mice leads to cranial dysmorphisms and defects of heart, brain, and bone, suggesting defects of cell fate determination. We used shRNA-mediated knockdown of NXN in SH-SY5Y neuroblastoma cells to study its impact on neuronal cells. We expected that shNXN cells would easily succumb to redox stress, but there were no differences in viability on stimulation with hydrogen peroxide. Instead, the proliferation of naïve shNXN cells was increased with a higher rate of mitotic cells in cell cycle analyses. In addition, basal respiratory rates were higher, whereas the relative change in oxygen consumption upon mitochondrial stressors was similar to control cells. shNXN cells had an increased expression of redox-sensitive heat shock proteins, Hsc70/HSPA8 and HSP90, and autophagy markers suggested an increase in autophagosome formation upon stimulation with bafilomycin and higher flux under low dose rapamycin. A high rate of self-renewal, autophagy, and upregulation of redox-sensitive chaperones appears to be an attractive anti-aging combination if it were to occur in neurons in vivo for which SH-SY5Y cells are a model.