Time- and cell-resolved dynamics of redox-sensitive Nrf2, HIF and NF-κB activities in 3D spheroids enriched for cancer stem cells

Kipp, Anna P.; Deubel, Stefanie; Arnér, Elias S.J.; Johansson, Katarina

doi:10.1016/j.redox.2017.03.013

Cited by 37 publications

(26 citation statements)

References 42 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We acknowledge the gift of the pTRAF plasmid from Elias Arnér, Division of Biochemistry, Department of Medical Biochemistry and Biophysics, Karolinska Institutet, Stockholm, Sweden. Colorectal carcinoma cell line HCT116 transformed with a pTRAF plasmid [ 18 , 33 ] were cultured in Dulbecco’s modified Eagle’s (DMEM) supplemented with 10% fetal bovine serum at 37°C in 5% CO 2 , 1% of penicillin/streptomycin and 0.1% of amphotericin B (Biochrom, United Kingdom). Cells were seeded in 96-well culture plates at a 1.0 x10 4 cells/cm 2 , and adhesion allowed for 24 hours.…”

Section: Methodsmentioning

confidence: 99%

Cytotoxicity of portoamides in human cancer cells and analysis of the molecular mechanisms of action

Ribeiro¹,

Lemos²,

Preto³

et al. 2017

PLoS ONE

View full text Add to dashboard Cite

Portoamides are cyclic peptides produced and released by the cyanobacterial strain Phormidium sp. presumably to interfere with other organisms in their ecosystems ("allelopathy"). Portoamides were previously demonstrated to have an antiproliferative effect on human lung carcinoma cells, but the underlying mechanism of this activity has not been described. In the present work, the effects of portoamides on proliferation were examined in eight human cancer cell lines and two non-carcinogenic cell lines, and major differences in sensitivities were observed. To generate hypotheses with regard to molecular mechanisms of action, quantitative proteomics using 2D gel electrophoresis and MALDI-TOF/TOF were performed on the colon carcinoma cell line HT-29. The expression of proteins involved in energy metabolism (mitochondrial respiratory chain and pentose phosphate pathway) was found to be affected. The hypothesis of altered energy metabolism was tested in further experiments. Exposure to portoamides resulted in reduced cellular ATP content, likely due to decreased mitochondrial energy production. Mitochondrial hyperpolarization and reduced mitochondrial reductive capacity was observed in treated cells. Furthermore, alterations in the expression of peroxiredoxins (PRDX4, PRDX6) and components of proteasome subunits (PSB4, PSA6) were observed in portoamide-treated cells, but these alterations were not associated with detectable increases in oxidative stress. We conclude that the cytotoxic activity of portoamides is associated with disturbance of energy metabolism, and alterations in mitochondrial structure and function.

show abstract

Section: Methodsmentioning

confidence: 99%

Cytotoxicity of portoamides in human cancer cells and analysis of the molecular mechanisms of action

Ribeiro¹,

Lemos²,

Preto³

et al. 2017

PLoS ONE

View full text Add to dashboard Cite

show abstract

“…HEK293 cells were transfected with the plasmid for transcription factor reporter activation based on fluores cence (pTRAF) vector, which uses expression of different fluorescent proteins as reporters for Nrf2 and NFB activities ( fig. S9A) (34). The pTRAF vector can also be used to investigate hypoxiainducible factor (HIF), but in our cellular models, HIF activation was minimal, so this parameter was not evaluated.…”

Section: Compounds Induce Nrf2 Activationmentioning

confidence: 99%

“…Nrf2 and NFB transcriptional activities were measured using the pTRAF tool as previously described (34). Briefly, HEK293 cells were seeded on black clearbottom collagen I-coated 96well plates (Biocoat 354649, BD Biosciences) at 20,000 cells per well a day before transfec tion with the pTRAFNrf2/HIF/NFB vector.…”

Section: Nrf2 and Nfb Transcriptional Activity Analysismentioning

confidence: 99%

Irreversible TrxR1 inhibitors block STAT3 activity and induce cancer cell death

et al. 2020

View full text Add to dashboard Cite

Because of its key role in cancer development and progression, STAT3 has become an attractive target for developing new cancer therapeutics. While several STAT3 inhibitors have progressed to advanced stages of development, their underlying biology and mechanisms of action are often more complex than would be expected from specific binding to STAT3. Here, we have identified and optimized a series of compounds that block STAT3-dependent luciferase expression with nanomolar potency. Unexpectedly, our lead compounds did not bind to cellular STAT3 but to another prominent anticancer drug target, TrxR1. We further identified that TrxR1 inhibition induced Prx2 and STAT3 oxidation, which subsequently blocked STAT3-dependent transcription. Moreover, previously identified inhibitors of STAT3 were also found to inhibit TrxR1, and likewise, established TrxR1 inhibitors block STAT3-dependent transcriptional activity. These results provide new insights into the complexities of STAT3 redox regulation while highlighting a novel mechanism to block aberrant STAT3 signaling in cancer cells.

show abstract

“…This includes TFs commonly viewed as stress-responsive like NRF2 (encoded by the gene NFE2L2 ), p53 (encoded by the gene TP53 ), HIF1α (encoded by the gene HIF1A ), as well as immunomodulatory TFs such as NF-κB, STAT, and the AP-1 complex (Fos/Jun), and more [8] , [9] , [10] , [11] , [12] , [13] , [14] , [15] . The range of processes regulated by these TFs is broad: factors like NRF2 and p53 regulate extensive gene networks responsible for mitigating ROS-induced damage, whereas HIF1α regulates the adaptive response to hypoxia [9] , [16] , [17] . Considering the number of redox-responsive TFs encoded within metazoan genomes, there is significant potential for crosstalk between these TF regulatory networks during the fine-tuning of gene expression changes in response to changing levels of oxygen or ROS.…”

Section: Introductionmentioning

confidence: 99%

Identification of a functional antioxidant response element at the HIF1A locus

et al. 2018

View full text Add to dashboard Cite

Reactive oxygen species (ROS), which are a byproduct of oxidative metabolism, serve as signaling molecules in a number of physiological settings. However, if their levels are not tightly maintained, excess ROS lead to potentially cytotoxic oxidative stress. Accordingly, several transcriptional regulatory networks have evolved to include components that are highly ROS-responsive. Depending on the context, these regulatory networks can leverage ROS to respond to nutrient conditions, metabolism, or other physiological signals, or to respond to oxidative stress. However, ROS signaling is complex, so regulatory interactions between various ROS-responsive transcription factors are still being mapped out. Here we show that the transcription factor NRF2, a key regulator of the adaptive response to oxidative stress, directly regulates expression of HIF1A, which encodes HIF1α, a key transcriptional regulator of the adaptive response to hypoxia. We used an integrative genomics approach to identify HIF1A as a ROS-responsive transcript and we found an NRF2-bound antioxidant response element (ARE) approximately 30 kilobases upstream of HIF1A. This ARE sequence is deeply conserved, and we verified that it is directly bound and activated by NRF2. In addition, we found that HIF1A is upregulated in breast and bladder tumors with high NRF2 activity. Taken together, our results demonstrate that NRF2 targets a functional ARE at the HIF1A locus, and reveal a direct regulatory connection between two important oxygen responsive transcription factors.

show abstract

Time- and cell-resolved dynamics of redox-sensitive Nrf2, HIF and NF-κB activities in 3D spheroids enriched for cancer stem cells

Cited by 37 publications

References 42 publications

Cytotoxicity of portoamides in human cancer cells and analysis of the molecular mechanisms of action

Cytotoxicity of portoamides in human cancer cells and analysis of the molecular mechanisms of action

Irreversible TrxR1 inhibitors block STAT3 activity and induce cancer cell death

Identification of a functional antioxidant response element at the HIF1A locus

Contact Info

Product

Resources

About