AMPKα1 confers survival advantage of colorectal cancer cells under metabolic stress by promoting redox balance through the regulation of glutathione reductase phosphorylation

Abstract Patients with stage II or III colorectal cancer (CRC) exhibit various clinical outcomes after radical treatments. The 5-year survival rate was between 50 and 87%. However, the underlying mechanisms of the variation remain unclear. Here we show that AMPKα1 is overexpressed in CRC patient specimens and the high expression is correlated with poor patient survival. We further reveal a previously unrecognized function of AMPKα1, which maintains high level of reduced glutathione to keep reduction–oxidation reaction (redox) homeostasis under stress conditions, thus promoting CRC cell survival under metabolic stress in vitro and enhancing tumorigenesis in vivo. Mechanistically, AMPKα1 regulate the glutathione reductase (GSR) phosphorylation possibly through residue Thr507 which enhances its activity. Suppression of AMPKα1 by using nano-sized polymeric vector induces a favorable therapeutic effect, especially when in combination with oxaliplatin. Our study uncovers a novel function of AMPKα1 in redox regulation and identifies a promising therapeutic strategy for treatment of CRC.

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Phytosomal Curcumin Elicits Anti-tumor Properties Through Suppression of Angiogenesis, Cell Proliferation and Induction of Oxidative Stress in Colorectal Cancer

Current Pharmaceutical Design ◽

10.2174/1381612825666190110145151 ◽

2019 ◽

Vol 24 (39) ◽

pp. 4626-4638 ◽

Cited By ~ 13

Author(s):

Reyhaneh Moradi-Marjaneh ◽

Seyed M. Hassanian ◽

Farzad Rahmani ◽

Seyed H. Aghaee-Bakhtiari ◽

Amir Avan ◽

...

Keyword(s):

Oxidative Stress ◽

Colorectal Cancer ◽

Therapeutic Potential ◽

Vegf Signaling ◽

Anticancer Effects ◽

Inhibition Of Angiogenesis ◽

Underlying Mechanisms ◽

Apoptotic Activity

Background: Colorectal cancer (CRC) is one of the most common causes of cancer-associated mortality in the world. Anti-tumor effect of curcumin has been shown in different cancers; however, the therapeutic potential of novel phytosomal curcumin, as well as the underlying molecular mechanism in CRC, has not yet been explored. Methods: The anti-proliferative, anti-migratory and apoptotic activity of phytosomal curcumin in CT26 cells was assessed by MTT assay, wound healing assay and Flow cytometry, respectively. Phytosomal curcumin was also tested for its in-vivo activity in a xenograft mouse model of CRC. In addition, oxidant/antioxidant activity was examined by DCFH-DA assay in vitro, measurement of malondialdehyde (MDA), Thiol and superoxidedismutase (SOD) and catalase (CAT) activity and also evaluation of expression levels of Nrf2 and GCLM by qRT-PCR in tumor tissues. In addition, the effect of phytosomal curcumin on angiogenesis was assessed by the measurement of VEGF-A and VEGFR-1 and VEGF signaling regulatory microRNAs (miRNAs) in tumor tissue. Results: Phytosomal curcumin exerts anti-proliferative, anti-migratory and apoptotic activity in-vitro. It also decreases tumor growth and augmented 5-fluorouracil (5-FU) anti-tumor effect in-vivo. In addition, our data showed that induction of oxidative stress and inhibition of angiogenesis through modulation of VEGF signaling regulatory miRNAs might be underlying mechanisms by which phytosomal curcumin exerted its antitumor effect. Conclusion: Our data confirmed this notion that phytosomal curcumin administrates anticancer effects and can be used as a complementary treatment in clinical settings.

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HSP90-dependent PUS7 overexpression facilitates the metastasis of colorectal cancer cells by regulating LASP1 abundance

Journal of Experimental & Clinical Cancer Research ◽

10.1186/s13046-021-01951-5 ◽

2021 ◽

Vol 40 (1) ◽

Author(s):

Dan Song ◽

Ming Guo ◽

Shuai Xu ◽

Xiaotian Song ◽

Bin Bai ◽

...

Keyword(s):

Colorectal Cancer ◽

Intellectual Development ◽

Molecular Mechanisms ◽

Hsp90 Inhibitor ◽

Pseudouridine Synthase ◽

Novel Approach ◽

Cell Metastasis ◽

Underlying Mechanisms

Abstract Background Pseudouridine synthase (PUS) 7 is a member of the PUS family that catalyses pseudouridine formation. It has been shown to be involved in intellectual development and haematological malignancies. Nevertheless, the role and the underlying molecular mechanisms of PUS7 in solid tumours, such as colorectal cancer (CRC), remain unexplored. This study elucidated, for the first time, the role of PUS7 in CRC cell metastasis and the underlying mechanisms. Methods We conducted immunohistochemistry, qPCR, and western blotting to quantify the expression of PUS7 in CRC tissues as well as cell lines. Besides, diverse in vivo and in vitro functional tests were employed to establish the function of PUS7 in CRC. RNA-seq and proteome profiling analysis were also applied to identify the targets of PUS7. PUS7-interacting proteins were further uncovered using immunoprecipitation and mass spectrometry. Results Overexpression of PUS7 was observed in CRC tissues and was linked to advanced clinical stages and shorter overall survival. PUS7 silencing effectively repressed CRC cell metastasis, while its upregulation promoted metastasis, independently of the PUS7 catalytic activity. LASP1 was identified as a downstream effector of PUS7. Forced LASP1 expression abolished the metastasis suppression triggered by PUS7 silencing. Furthermore, HSP90 was identified as a client protein of PUS7, associated with the increased PUS7 abundance in CRC. NMS-E973, a specific HSP90 inhibitor, also showed higher anti-metastatic activity when combined with PUS7 repression. Importantly, in line with these results, in human CRC tissues, the expression of PUS7 was positively linked to the expression of HSP90 and LASP1, and patients co-expressing HSP90/PUS7/LASP1 showed a worse prognosis. Conclusions The HSP90-dependent PUS7 upregulation promotes CRC cell metastasis via the regulation of LASP1. Thus, targeting the HSP90/PUS7/LASP1 axis may be a novel approach for the treatment of CRC.

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N-Acetylcysteine as Modulator of the Essential Trace Elements Copper and Zinc

Antioxidants ◽

10.3390/antiox9111117 ◽

2020 ◽

Vol 9 (11) ◽

pp. 1117

Author(s):

Theresa Wolfram ◽

Maria Schwarz ◽

Michaela Reuß ◽

Kristina Lossow ◽

Mario Ost ◽

...

Keyword(s):

Trace Elements ◽

Redox Homeostasis ◽

Redox Balance ◽

Cellular Redox ◽

Essential Trace Elements ◽

Nrf2 Activation ◽

Zn And Cu In ◽

Cu And Zn

N-acetylcysteine (NAC) is a frequently prescribed drug and known for its metal chelating capability. However, to date it is not well characterized whether NAC intake affects the homeostasis of essential trace elements. As a precursor of glutathione (GSH), NAC also has the potential to modulate the cellular redox homeostasis. Thus, we aimed to analyze effects of acute and chronic NAC treatment on the homeostasis of copper (Cu) and zinc (Zn) and on the activity of the redox-sensitive transcription factor Nrf2. Cells were exposed to 1 mM NAC and were co-treated with 50 μM Cu or Zn. We showed that NAC treatment reduced the cellular concentration of Zn and Cu. In addition, NAC inhibited the Zn-induced Nrf2 activation and limited the concomitant upregulation of cellular GSH concentrations. In contrast, mice chronically received NAC via drinking water (1 g NAC/100 mL). Cu and Zn concentrations were decreased in liver and spleen. In the duodenum, NQO1, TXNRD, and SOD activities were upregulated by NAC. All of them can be induced by Nrf2, thus indicating a putative Nrf2 activation. Overall, NAC modulates the homeostasis of Cu and Zn both in vitro and in vivo and accordingly affects the cellular redox balance.

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UPF1 Promotes Chemoresistance to Oxaliplatin Through Maintenance of Stemness by Increasing Phosphorylated TOP2A in Colorectal Cancer.

10.21203/rs.3.rs-130880/v1 ◽

2020 ◽

Author(s):

Congcong Zhu ◽

Long Zhang ◽

Senlin Zhao ◽

Weixing Dai ◽

Yun Xu ◽

...

Keyword(s):

Colorectal Cancer ◽

Overall Survival ◽

Cell Lines ◽

Clinical Relevance ◽

Poor Prognosis ◽

Therapy Strategy ◽

Underlying Mechanisms

Abstract Background: UPF1 is proved to dysregulate in multiple tumors and influence carcinogenesis. However, the role of UPF1 on oxaliplatin resistance in colorectal cancer (CRC) remains unknown.Methods: Firstly, we investigated the clinical relevance of UPF1 in CRC patients. Then, we explored the influence of UPF1 on chemoresistance to oxaliplatin in vitro and in vivo. Finally, we disclosed the underlying mechanisms of oxaliplatin resistance induced by UPF1.Results: UPF1 is upregulated in CRC and overexpression of UPF1 more likely results in recurrence in CRC patients and predicts a poorer overall survival (OS). UPF1 maintains stemness in CRC cell lines and promotes chemoresistance to oxaliplatin in CRC. UPF1-induced oxaliplatin resistance can be associated with interaction with TOP2A and increasing phosphorylated TOP2A.Conclusions: UPF1 was overexpressed and predicted a poor prognosis in CRC. UPF1 enhanced the stemness and chemoresistance to oxaliplatin by interaction with TOP2A and increase of phosphorylated TOP2A in CRC, which may provide a new therapy strategy for chemoresistance to oxaliplatin in CRC patients.

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Exosome-Derived ADAM17 Promotes Liver Metastasis in Colorectal Cancer

Frontiers in Pharmacology ◽

10.3389/fphar.2021.734351 ◽

2021 ◽

Vol 12 ◽

Author(s):

Jinbing Sun ◽

Zhihua Lu ◽

Wei Fu ◽

Kuangyi Lu ◽

Xiuwen Gu ◽

...

Keyword(s):

Colorectal Cancer ◽

Metastatic Colorectal Cancer ◽

Cancer Cells ◽

Cancer Metastasis ◽

Metastatic Niche ◽

Colorectal Cancer Cells ◽

Niche Formation ◽

Underlying Mechanisms

Exosomes derived from cancer cells are deemed important drivers of pre-metastatic niche formation at distant organs, but the underlying mechanisms of their effects remain largely unknow. Although the role of ADAM17 in cancer cells has been well studied, the secreted ADAM17 effects transported via exosomes are less understood. Herein, we show that the level of exosome-derived ADAM17 is elevated in the serum of patients with metastatic colorectal cancer as well as in metastatic colorectal cancer cells. Furthermore, exosomal ADAM17 was shown to promote the migratory ability of colorectal cancer cells by cleaving the E-cadherin junction. Moreover, exosomal ADAM17 overexpression as well as RNA interference results highlighted its function as a tumor metastasis-promoting factor in colorectal cancer in vitro and in vivo. Taken together, our current work suggests that exosomal ADAM17 is involved in pre-metastatic niche formation and may be utilized as a blood-based biomarker of colorectal cancer metastasis.

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Arabidopsis glutathione reductase 2 is indispensable in plastids, while mitochondrial glutathione is safeguarded by additional reduction and transport systems

10.1101/610477 ◽

2019 ◽

Cited By ~ 1

Author(s):

Laurent Marty ◽

Daniela Bausewein ◽

Christopher Müller ◽

Sajid Ali Khan Bangash ◽

Anna Moseler ◽

...

Keyword(s):

Glutathione Reductase ◽

Redox Regulation ◽

Redox Homeostasis ◽

Immunogold Labelling ◽

Transport Systems ◽

List Type ◽

Iron Sulfur Cluster ◽

Thioredoxin System ◽

Glutathione Redox

SummaryA highly negative glutathione redox potential (EGSH) is maintained in the cytosol, plastids and mitochondria of plant cells to support fundamental processes, including antioxidant defence, redox regulation and iron-sulfur cluster biogenesis. Out of two glutathione reductase (GR) proteins in Arabidopsis, GR2 is predicted to be dual-targeted to plastids and mitochondria, but its differential roles in these organelles remain unclear.We dissected the role of GR2 in organelle glutathione redox homeostasis and plant development using a combination of genetic complementation and stacked mutants, biochemical activity studies, immunogold labelling and in vivo biosensing.Our data demonstrate that GR2 is dual-targeted to plastids and mitochondria, but embryo lethality of gr2 null mutants is caused specifically in plastids. Whereas lack of mitochondrial GR2 leads to a partially oxidised glutathione pool in the matrix, the ABC transporter ATM3 and the mitochondrial thioredoxin system provide functional backup and maintain plant viability.We identify GR2 as essential in the plastid stroma, where it counters GSSG accumulation and developmental arrest. By contrast a functional triad of GR2, ATM3 and the thioredoxin system in the mitochondria provides resilience to excessive glutathione oxidation.

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TCF4 and HuR Mediated-METTL14 Suppresses Dissemination of Colorectal Cancer via N6-Methyladenosine-Dependent Silencing of ARRDC4

10.21203/rs.3.rs-648817/v1 ◽

2021 ◽

Author(s):

Hao Wang ◽

Wei Wei ◽

Zhong-Yuan Zhang ◽

Yao Liu ◽

Bin Shi ◽

...

Keyword(s):

Colorectal Cancer ◽

Chromatin Immunoprecipitation ◽

Dependent Manner ◽

Dot Blot ◽

Downstream Target ◽

In Vivo Assays ◽

Rna Immunoprecipitation ◽

Underlying Mechanisms

Abstract Background: Metastasis remains the major obstacle to improved survival for colorectal cancer (CRC) patients. Dysregulation of N6-methyladenosine (m6A) is causally associated with the development of metastasis through poorly understood mechanisms. Methods: The expression of METTL14 and its correlation with clinicopathological features were evaluated by western blot and immunohistochemistry. The roles of METTL14 in CRC metastasis were determined through in vitro and in vivo assays. The underlying mechanisms of METTL14 regulation were explored using transcriptome-sequencing, m6A-seguencing, methylated RNA immunoprecipitation (MeRIP), m6A dot blot, RNA immunoprecipitation (RIP) and chromatin immunoprecipitation (ChIP) assay.Results: METTL14 is functionally related to the inhibition of ARRDC4/ZEB1 signaling and to the consequent suppression of CRC metastasis. We unveil METTL14-mediated m6A modification profile and identify ARRDC4 as a direct downstream target of METTL14. Knockdown of METTL14 significantly enhances ARRDC4 mRNA stability relying on the “reader” protein YHTDF2 dependent manner. Moreover, TCF4 can induce METTL14 protein expression, and HuR suppresses METTL14 expression by directly binding to its promoter. Clinically, decreased METTL14 is correlated with poor prognosis and acts as an independent predictor of CRC survival. Conclusion: Our data suggest that TCF4 and HuR mediated-METTL14 can trigger the metastasis of CRC during cancer development via YHTDF2/ARRDC4/ZEB1 axis, which imposes great challenge that inhibition of METTL14 is a potential approach for cancer treatment.

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The Association of Aberrant Expression of FGF1 and mTOR-S6K1 in Colorectal Cancer

Frontiers in Oncology ◽

10.3389/fonc.2021.706838 ◽

2021 ◽

Vol 11 ◽

Author(s):

Tinghui Duan ◽

Diyuan Zhou ◽

Yizhou Yao ◽

Xinyu Shao

Keyword(s):

Colorectal Cancer ◽

Malignant Neoplasms ◽

Aberrant Expression ◽

Protein Levels ◽

And Migration ◽

High Level ◽

Proliferation And Migration

Colorectal cancer (CRC) is one of the most frequent malignant neoplasms worldwide, and the effect of treatments is limited. Fibroblast growth factor 1 (FGF1) has been involved in a wide variety of several malignant diseases and takes part in the tumorigenesis of CRC. However, the function and mechanism of FGF1 in CRC remains elusive. In this study, the results indicated that FGF1 is elevated in CRC tissues and linked with poor prognosis (P < 0.001). In subgroup analysis of FGF1 in CRC, regardless of any clinic-factors except gender, high level FGF1 expression was associated with markedly shorter survival (P < 0.05). In addition, the expression of p-S6K1 and FGF1 was not associated in normal tissue (P = 0.781), but their expression was closely related in tumor tissue (P = 0.010). The oncogenic role of FGF1 was determined using in vitro and in vivo functional assays. FGF1 depletion inhibited the proliferation and migration of CRC cells in vitro and vivo. FGF1 was also significantly correlated with mTOR-S6K1 pathway on the gene and protein levels (P < 0.05). In conclusion, FGF1 acts as a tumor activator in CRC, and against FGF1 may provide a new visual field on treating CRC, especially for mTORC1-targeted resistant patients.

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Circ3823 contributes to growth, metastasis and angiogenesis of colorectal cancer: involvement of miR-30c-5p/TCF7 axis

Molecular Cancer ◽

10.1186/s12943-021-01372-0 ◽

2021 ◽

Vol 20 (1) ◽

Author(s):

Yaxin Guo ◽

Yuying Guo ◽

Chen Chen ◽

Dandan Fan ◽

Xiaoke Wu ◽

...

Keyword(s):

Colorectal Cancer ◽

In Situ Hybridization ◽

Tumour Growth ◽

Luciferase Reporter ◽

Circular Rnas ◽

Repressive Effect ◽

Underlying Mechanisms

Abstract Background Colorectal cancer (CRC) is one of the most common malignant tumours. The recurrence and metastasis of CRC seriously affect the survival rate of patients. Angiogenesis is an extremely important cause of tumour growth and metastasis. Circular RNAs (circRNAs) have been emerged as vital regulators for tumour progression. However, the regulatory role, clinical significance and underlying mechanisms still remain largely unknown. Methods High-throughput sequencing was used to analyse differential circRNAs expression in tumour and non-tumour tissues of CRC. In situ hybridization (ISH) and qRT-PCR were used to determine the level of circ3823 in CRC tissues and serum samples. Then, functional experiments in vitro and in vivo were performed to investigate the effects of circ3823 on tumour growth, metastasis and angiogenesis in CRC. Sanger sequencing, RNase R and Actinomycin D assay were used to verify the ring structure of circ3823. Mechanistically, dual luciferase reporter assay, fluorescent in situ hybridization (FISH), RNA immunoprecipitation (RIP) and RNA pull-down experiments were performed to confirm the underlying mechanisms of circ3823. Results Circ3823 was evidently highly expressed in CRC and high circ3823 expression predicted a worse prognosis of CRC patients. Receiver operating characteristic curves (ROCs) indicated that the expression of circ3823 in serum showed high sensitivity and specificity for detecting CRC which means circ3823 have the potential to be used as diagnostic biomarkers. Functional experiments in vitro and in vivo indicated that circ3823 promote CRC cell proliferation, metastasis and angiogenesis. Mechanism analysis showed that circ3823 act as a competing endogenous RNA of miR-30c-5p to relieve the repressive effect of miR-30c-5p on its target TCF7 which upregulates MYC and CCND1, and finally facilitates CRC progression. In addition, we found that N6-methyladenosine (m6A) modification exists on circ3823. And the m6A modification is involved in regulating the degradation of circ3823. Conclusions Our findings suggest that circ3823 promotes CRC growth, metastasis and angiogenesis through circ3823/miR-30c-5p/TCF7 axis and it may serve as a new diagnostic marker or target for treatment of CRC patients. In addition, m6A modification is involved in regulating the degradation of circ3823.

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Parkinson Disease-Linked Parkin Mediates Redox Reactions That Lower Oxidative Stress In Mammalian Brain

10.1101/2020.04.26.062380 ◽

2020 ◽

Cited By ~ 1

Author(s):

Daniel N. El Kodsi ◽

Jacqueline M. Tokarew ◽

Rajib Sengupta ◽

Nathalie A. Lengacher ◽

Andy C. Ng ◽

...

Keyword(s):

Oxidative Stress ◽

Reductase Activity ◽

Redox Homeostasis ◽

Redox Balance ◽

Oxidative Modification ◽

Reduced Form ◽

Mammalian Brain ◽

Anti Oxidant

SUMMARYWe recently hypothesized that parkin plays a role in redox homeostasis and provided evidence that it directly reduces hydrogen peroxide (H2O2) in vitro. Here, we examined this anti-oxidant activity in vivo. Informed by findings in human brain, we demonstrate that elevated oxidative stress promotes parkin insolubility in mice. In normal mouse brain parkin was partially oxidized, e.g., at cysteines 195 and 252, which was augmented by oxidative stress. Although under basal conditions H2O2 levels were unchanged in adult prkn-/- brain, a parkin-dependent reduction of cytosolic H2O2 was observed when mitochondria were impaired, either due to neurotoxicant exposure (MPTP) or Sod2 haploinsufficiency. In accordance, markers of oxidative stress, e.g., protein carbonylation and nitrotyrosination, were elevated in the cytosol but not in mitochondria from prkn-/- mice. Nevertheless, this rise in oxidative stress led to changes in mitochondrial enzyme activities and the metabolism of glutathione in cells and mammalian brain. In parkin’s absence reduced glutathione concentrations were increased including in human cortex. This compensation was not due to new glutathione synthesis but attributed to elevated oxidized glutathione (GSSG)-reductase activity. Moreover, we discovered that parkin also recycled GSSG to its reduced form. With this reaction, parkin became S-glutathionylated, e.g., at cysteines 59 and human-specific 95. This oxidative modification was reversed by glutaredoxin. Our results demonstrate that cytosolic parkin mediates anti-oxidant reactions including H2O2 reduction and glutathione regeneration. These reducing activities lead to a range of oxidative modifications in parkin itself. In parkin-deficient brain oxidative stress rises despite changes to maintain redox balance.

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