scholarly journals RSL3 Drives Ferroptosis through NF-κB Pathway Activation and GPX4 Depletion in Glioblastoma

2021 ◽  
Vol 2021 ◽  
pp. 1-10
Author(s):  
Shengbiao Li ◽  
Yuping He ◽  
Kexin Chen ◽  
Jiaojiao Sun ◽  
Lulu Zhang ◽  
...  

Glioblastoma, the most aggressive form of malignant glioma, is very difficult to treat because of its aggressively invasive nature and high recurrence rates. RAS-selective lethal 3 (RSL3), a well-known inhibitor of glutathione peroxidase 4 (GPX4), could effectively induce oxidative cell death in glioblastoma cells through ferroptosis, and several signaling pathways are involved in this process. However, the role of the nuclear factor kappa-B (NF-κB) pathway in glioblastoma cell ferroptosis has not yet been investigated. Therefore, we aimed to clarify the underlying mechanism of the NF-κB pathway in RSL3-induced ferroptosis in glioblastoma cells. We found that RSL3 led to an increase in lipid ROS concentration and downregulation of ferroptosis-related proteins such as GPX4, ATF4, and SLC7A11 (xCT) in glioblastoma cells. Additionally, the NF-κB pathway was activated by RSL3, and its inhibition by BAY 11-7082 could alleviate ferroptosis. The murine xenograft tumor model indicated that NF-κB pathway inhibition could mitigate the antitumor effects of RSL3 in vivo. Furthermore, we found that GPX4 knockdown could not effectively induce ferroptosis. However, NF-κB pathway activation coupled with GPX4 silencing induced ferroptosis. Additionally, ATF4 and xCT expression might be regulated by the NF-κB pathway. Collectively, our results revealed that the NF-κB pathway plays a novel role in RSL3-induced ferroptosis in glioblastoma cells and provides a new therapeutic strategy for glioblastoma treatment.

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Chunyang Li ◽  
Shuangqing Yang ◽  
Huaqing Ma ◽  
Mengjia Ruan ◽  
Luyan Fang ◽  
...  

Abstract Background Cervical cancer is a type of the most common gynecology tumor in women of the whole world. Accumulating data have shown that icariin (ICA), a natural compound, has anti-cancer activity in different cancers, including cervical cancer. The study aimed to reveal the antitumor effects and the possible underlying mechanism of ICA in U14 tumor-bearing mice and SiHa cells. Methods The antitumor effects of ICA were investigated in vivo and in vitro. The expression of TLR4/MyD88/NF-κB and Wnt/β-catenin signaling pathways were evaluated. Results We found that ICA significantly suppressed tumor tissue growth and SiHa cells viability in a dose-dependent manner. Also, ICA enhanced the anti-tumor humoral immunity in vivo. Moreover, ICA significantly improved the composition of the microbiota in mice models. Additionally, the results clarified that ICA significantly inhibited the migration, invasion capacity, and expression levels of TGF-β1, TNF-α, IL-6, IL-17A, IL-10 in SiHa cells. Meanwhile, ICA was revealed to promote the apoptosis of cervical cancer cells by down-regulating Ki67, survivin, Bcl-2, c-Myc, and up-regulating P16, P53, Bax levels in vivo and in vitro. For the part of mechanism exploration, we showed that ICA inhibits the inflammation, proliferation, migration, and invasion, as well as promotes apoptosis and immunity in cervical cancer through impairment of TLR4/MyD88/NF-κB and Wnt/β-catenin pathways. Conclusions Taken together, ICA could be a potential supplementary agent for cervical cancer treatment.


Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3812
Author(s):  
Mai-Huong T. Ngo ◽  
Sue-Wei Peng ◽  
Yung-Che Kuo ◽  
Chun-Yen Lin ◽  
Ming-Heng Wu ◽  
...  

The role of a YAP-IGF-1R signaling loop in HCC resistance to sorafenib remains unknown. Method: Sorafenib-resistant cells were generated by treating naïve cells (HepG2215 and Hep3B) with sorafenib. Different cancer cell lines from databases were analyzed through the ONCOMINE web server. BIOSTORM–LIHC patient tissues (46 nonresponders and 21 responders to sorafenib) were used to compare YAP mRNA levels. The HepG2215_R-derived xenograft in SCID mice was used as an in vivo model. HCC tissues from a patient with sorafenib failure were used to examine differences in YAP and IGF-R signaling. Results: Positive associations exist among the levels of YAP, IGF-1R, and EMT markers in HCC tissues and the levels of these proteins increased with sorafenib failure, with a trend of tumor-margin distribution in vivo. Blocking YAP downregulated IGF-1R signaling-related proteins, while IGF-1/2 treatment enhanced the nuclear translocation of YAP in HCC cells through PI3K-mTOR regulation. The combination of YAP-specific inhibitor verteporfin (VP) and sorafenib effectively decreased cell viability in a synergistic manner, evidenced by the combination index (CI). Conclusion: A YAP-IGF-1R signaling loop may play a role in HCC sorafenib resistance and could provide novel potential targets for combination therapy with sorafenib to overcome drug resistance in HCC.


2021 ◽  
pp. 1-11
Author(s):  
Hanqing Chen ◽  
Xiru Xu ◽  
Zhengqing Liu ◽  
Yong Wu

Hypertension is considered a risk factor for a series of systematic diseases. Known factors including genetic predisposition, age, and diet habits are strongly associated with the initiation of hypertension. The current study aimed to investigate the role of miR-22-3p in hypertension. In this study, we discovered that the miR-22-3p level was significantly decreased in the thoracic aortic vascular tissues and aortic smooth muscle cells (ASMCs) of spontaneously hypertensive rats. Functionally, the overexpression of miR-22-3p facilitated the switch of ASMCs from the synthetic to contractile phenotype. To investigate the underlying mechanism, we predicted 11 potential target mRNAs for miR-22-3p. After screening, chromodomain helicase DNA-binding 9 (CHD9) was validated to bind with miR-22-3p. Rescue assays showed that the co-overexpression of miR-22-3p and CHD9 reversed the inhibitory effect of miR-22-3p mimics on cell proliferation, migration, and oxidative stress in ASMCs. Finally, miR-22-3p suppressed vascular remodeling and oxidative stress in vivo. Overall, miR-22-3p regulated ASMC phenotype switch by targeting CHD9. This new discovery provides a potential insight into hypertension treatment.


2021 ◽  
Vol 12 ◽  
Author(s):  
Jiaji Hu ◽  
Hanglu Ying ◽  
Jie Yao ◽  
Longhe Yang ◽  
Wenhui Jin ◽  
...  

Nonalcoholic steatohepatitis (NASH) has become one of the serious causes of chronic liver diseases, characterized by hepatic steatosis, hepatocellular injury, inflammation and fibrosis, and lack of efficient therapeutic agents. Palmitoylethanolamide (PEA) is an endogenous bioactive lipid with various pharmacological activities, including anti-inflammatory, analgesic, and neuroprotective effects. However, the effect of PEA on nonalcoholic steatohepatitis is still unknown. Our study aims to explore the potential protective role of PEA on NASH and to reveal the underlying mechanism. In this study, the C57BL/6 mice were used to establish the NASH model through methionine- and choline-deficient (MCD) diet feeding. Here, we found that PEA treatment significantly improved liver function, alleviated hepatic pathological changes, and attenuated the lipid accumulation and hepatic fibrosis in NASH mice induced by MCD diet feeding. Mechanistically, the anti-steatosis effect of PEA may be due to the suppressed expression of ACC1 and CD36, elevated expression of PPAR-α, and the phosphorylation levels of AMPK. In addition, hepatic oxidative stress was greatly inhibited in MCD-fed mice treated with PEA via enhancing the expression and activities of antioxidant enzymes, including GSH-px and SOD. Moreover, PEA exerted a clear anti-inflammatory effect though ameliorating the expression of inflammatory mediators and suppressing the NLRP3 inflammasome pathway activation. Furthermore, the impaired autophagy in MCD-induced mice was reactivated with PEA treatment. Taken together, our research suggested that PEA protects against NASH through the inhibition of inflammation and restoration of autophagy. Thus, PEA may represent an efficient therapeutic agent to treat NASH.


2021 ◽  
Author(s):  
Suwei Dong ◽  
Yanbin Xiao ◽  
Ziqiang Zhu ◽  
Xiang Ma ◽  
Zhuohui Peng ◽  
...  

Abstract Background: Due to constitutive or acquired non-sensitive to cytotoxic agents, the prognosis of osteosarcoma remains unfavorable. It’s has been proved that metformin could enhance the chemosensitivity of cancer cells to anticancer drugs. A novel finding states that IGF-1R involves in cancer chemoresistance, However, whether IGF-1R play a role in metformin-induced osteosarcoma chemosensitivity is incompletely understood. Hence, the current study aimed to elucidate the role of metformin in OS cell chemosensitivity modulation to identify the underlying mechanism of metformin regulating the IGF-1R/miR-610/FEN1 signaling.Methods: Immunohistochemistry and qRT-PCR were used to evaluate the expression pattern of IGF-1R, miR-610 and FEN1 in osteosarcoma and paired normal tissues. Western blot and qRT-PCR were performed to determine changes in expression of key molecules in the IGF-1R/miR-610/FEN1 signaling pathway after various treatments. The direct modulation between miR-610 and FEN1 was monitored by luciferase reporter assay. Osteosarcoma cell sensitivity to chemotherapy was detected by MTS assay. In vivo experiments were conducted to further verify the role of the metformin in the chemosensitivity modulation of OS cells to ADM.Results: We found that IGF-1R, miR-610 and FEN1 were abberently expressed in osteosarcoma, and participated in apoptosis modulation (p < 0.05). We found that this effect was abated by metformin treatment. Luciferase reporter assays confirmed that FEN1 is a direct target of miR-610. Moreover, we observed that metformin treatment decreased IGF-1R and FEN1, but elevated miR-610 expression. Metformin sensitized OS cells to cytotoxic agents, while overexpression of FEN1 compromised the sensitizing effects of metformin partly. Furthermore, metformin was observed to enforce the ADM treatment effect in nude mice xenograft models.Conclusions: Overall, metformin enhanced the sensitivity of OS cells to cytotoxic agents via the IGF-1R/miR-610/FEN1 signaling axis, highlighting the capacity of metformin as an adjunct to the chemotherapy of OS.


2008 ◽  
Vol 74 (12) ◽  
pp. 3644-3651 ◽  
Author(s):  
Wook Kim ◽  
Stuart B. Levy

ABSTRACT The annotation process of a newly sequenced bacterial genome is largely based on algorithms derived from databases of previously defined RNA and protein-encoding gene structures. This process generally excludes the possibility that the two strands of a given stretch of DNA can each harbor a gene in an overlapping manner. While the presence of such structures in eukaryotic genomes is considered to be relatively common, their counterparts in prokaryotic genomes are just beginning to be recognized. Application of an in vivo expression technology has previously identified 22 discrete genetic loci in Pseudomonas fluorescens Pf0-1 that were specifically activated in the soil environment, of which 10 were present in an antisense orientation relative to previously annotated genes. This observation led to the hypothesis that the physiological role of overlapping genetic structures may be relevant to growth conditions outside artificial laboratory media. Here, we examined the role of one of the overlapping gene pairs, iiv19 and leuA2, in soil. Although iiv19 was previously demonstrated to be preferentially activated in the soil environment, its absence did not alter the ability of P. fluorescens to colonize or survive in soil. Surprisingly, the absence of the leuA2 gene conferred a fitness advantage in the soil environment when leucine was supplied exogenously. This effect was determined to be independent of the iiv19 gene, and further analyses revealed that amino acid antagonism was the underlying mechanism behind the observed fitness advantage of the bacterium in soil. Our findings provide a potential mechanism for the frequent occurrence of auxotrophic mutants of Pseudomonas spp. in the lungs of cystic fibrosis patients.


2020 ◽  
Vol 698 ◽  
pp. 134294 ◽  
Author(s):  
Zhuo Ma ◽  
Can Wang ◽  
Chang Liu ◽  
Dong-Ying Yan ◽  
Xuan Tan ◽  
...  
Keyword(s):  

Nanomedicine ◽  
2019 ◽  
Vol 14 (16) ◽  
pp. 2189-2207
Author(s):  
Yiming Yu ◽  
Li Zhang ◽  
Miao Wang ◽  
Zhe Yang ◽  
Leping Lin ◽  
...  

Aim: To develop a H2O2/near-infrared (NIR) laser light-responsive nanoplatform (manganese-doped Prussian blue@polypyrrole [MnPB@PPy]) for synergistic chemo/photothermal cancer theranostics. Materials & methods: Doxorubicin (DOX) was loaded onto the surface of polypyrrole shells. The in vitro and in vivo MRI performance and anticancer effects of these nanoparticles (NPs) were evaluated. Results: The MnPB@PPy NPs could not only generate heat under NIR laser irradiation for cancer photothermal therapy but also act as an excellent MRI contrast agent. The loaded DOX could be triggered to release by both NIR light and H2O2 to enhance synergistic therapeutic efficacy. The antitumor effects were confirmed by in vitro cellular cytotoxicity assays and in vivo treatment in a xenograft tumor model. Conclusion: The designed H2O2/NIR light-responsive MnPB@PPy-DOX NPs hold great potential for future biomedical applications.


2017 ◽  
Vol 312 (1) ◽  
pp. E27-E36 ◽  
Author(s):  
Servane Le Plénier ◽  
Arthur Goron ◽  
Athanassia Sotiropoulos ◽  
Eliane Archambault ◽  
Chantal Guihenneuc ◽  
...  

Citrulline (CIT) is an endogenous amino acid produced by the intestine. Recent literature has consistently shown CIT to be an activator of muscle protein synthesis (MPS). However, the underlying mechanism is still unknown. Our working hypothesis was that CIT might regulate muscle homeostasis directly through the mTORC1/PI3K/MAPK pathways. Because CIT undergoes both interorgan and intraorgan trafficking and metabolism, we combined three approaches: in vivo, ex vivo, and in vitro. Using a model of malnourished aged rats, CIT supplementation activated the phosphorylation of S6K1 and 4E-BP1 in muscle. Interestingly, the increase in S6K1 phosphorylation was positively correlated ( P < 0.05) with plasma CIT concentration. In a model of isolated incubated skeletal muscle from malnourished rats, CIT enhanced MPS (from 30 to 80% CIT vs. Ctrl, P < 0.05), and the CIT effect was abolished in the presence of wortmannin, rapamycin, and PD-98059. In vitro, on myotubes in culture, CIT led to a 2.5-fold increase in S6K1 phosphorylation and a 1.5-fold increase in 4E-BP1 phosphorylation. Both rapamycin and PD-98059 inhibited the CIT effect on S6K1, whereas only LY-294002 inhibited the CIT effect on both S6K1 and 4E-BP1. These findings show that CIT is a signaling agent for muscle homeostasis, suggesting a new role of the intestine in muscle mass control.


Blood ◽  
2005 ◽  
Vol 106 (11) ◽  
pp. 2975-2975 ◽  
Author(s):  
Asher Alban Chanan-Khan ◽  
Swaminathan Padmanabhan ◽  
Kena C. Miller ◽  
Paula Pera ◽  
Laurie DiMiceli ◽  
...  

Abstract Introduction: L is a more potent analogue of thalidomide with antitumor activity reported in MDS and multiple myeloma. Clinical anti-leukemic activity of L is reported for the first time by our group in pts with CLL. The underlying mechanism of its antitumor activity remains undetermined. We investigated the effect of L on the tumor microenvironment and studied the modulation of soluble cytokines and immune cells (T and NK cells) in pts receiving L. Patients and Methods: CLL pts enrolled on the clinical study with L were eligible. Pre and post (day 7) samples were obtained for evaluation of changes in serum cytokine and immune cell environment. Malignant cells were also obtained to investigate the in vitro antitumor activity of L prior to initiating treatment on clinical trial. Results: With Anexin V staining for evaluation of apoptosis induction, in vitro testing of pts samples (n=10) showed only a modest increase in apoptosis at 200mg of L - levels clinically not achievable. Yet same pts treated with L on clinical study showed significant antitumor response, suggesting the mechanism to be possibly related to modulation of the tumor microenvironment. In evaluation of the tumor cytokine microenvironment (n= 10) we noted significant L induced increase in IL-10 (n=6), IL-8 (n=8), IP-10 (n=10), IL-8 (n=8), TNF-alpha (n=4) and decrease in PDGF (n=5) and RANTES (n=5). While evaluation of the immune cell repertoire we observed an absolute increase in T-cell as well as NK-cell after treatment with L. Conclusion: Our in vitro evaluation does not suggest a direct apoptotic effect of L on the malignant CLL cells and thus support the hypothesis that the anti-leukemic effect noted in the clinical trial (reported separately) is most likely from in vivo modulation of the tumor microenvironment as is demonstrated from changes in the cytokine milieu and the cellular immune response. Collectively these changes may be responsible for the immune modulating properties of L and the resultant anti-CLL activity in pts.


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