scholarly journals Radiosensitizing performance of uncoated and citrate-coated SPIONs in cancerous and non-cancerous cells

Author(s):  
Carola Kryschi ◽  
W. Neuhuber ◽  
Damjana Drobne ◽  
Luitpold V. R. Distel ◽  
Stefanie Klein ◽  
...  

Superparamagnetic iron oxide nanoparticles were shown to exhibit a high performance as X-ray dosage enhancer in tumor cells. The radio-enhancing potential of uncoated and citrate-coated SPIONs was comprehensively studied for tumor and healthy cells. Pristine and citrate-coated SPIONs drastically differ in their water dispersibility and adsorption affinity for proteins. The activities of antioxidant enzymes in the healthy cells were shown to be significantly distinct from those in the tumor cells as containing a much higher H2O2 concentration. Pristine SPIONs catalyzed the Fenton reaction of hydrogen peroxide to the highly reactive hydroxyl radical in all cell types. In contrast, intracellular citrate-stabilized SPIONs were shown t o be non-toxic and to do not affect the formation of reactive oxygen species. X-ray irradiation of citrate-stabilized SPIONs, when internalized by tumor cells, significantly boost the formation of hydroxyl radicals, whereas the healthy cells preserved their initial levels of reactive oxygen species.

2020 ◽  
Vol 21 (5) ◽  
pp. 477-498
Author(s):  
Yongfeng Chen ◽  
Xingjing Luo ◽  
Zhenyou Zou ◽  
Yong Liang

Reactive oxygen species (ROS), an important molecule inducing oxidative stress in organisms, play a key role in tumorigenesis, tumor progression and recurrence. Recent findings on ROS have shown that ROS can be used to treat cancer as they accelerate the death of tumor cells. At present, pro-oxidant drugs that are intended to increase ROS levels of the tumor cells have been widely used in the clinic. However, ROS are a double-edged sword in the treatment of tumors. High levels of ROS induce not only the death of tumor cells but also oxidative damage to normal cells, especially bone marrow hemopoietic cells, which leads to bone marrow suppression and (or) other side effects, weak efficacy of tumor treatment and even threatening patients’ life. How to enhance the killing effect of ROS on tumor cells while avoiding oxidative damage to the normal cells has become an urgent issue. This study is a review of the latest progress in the role of ROS-mediated programmed death in tumor treatment and prevention and treatment of oxidative damage in bone marrow induced by ROS.


Antioxidants ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1243
Author(s):  
Eunus S. Ali ◽  
Grigori Y. Rychkov ◽  
Greg J. Barritt

TRPM2 channels admit Ca2+ and Na+ across the plasma membrane and release Ca2+ and Zn2+ from lysosomes. Channel activation is initiated by reactive oxygen species (ROS), leading to a subsequent increase in ADP-ribose and the binding of ADP-ribose to an allosteric site in the cytosolic NUDT9 homology domain. In many animal cell types, Ca2+ entry via TRPM2 channels mediates ROS-initiated cell injury and death. The aim of this review is to summarise the current knowledge of the roles of TRPM2 and Ca2+ in the initiation and progression of chronic liver diseases and acute liver injury. Studies to date provide evidence that TRPM2-mediated Ca2+ entry contributes to drug-induced liver toxicity, ischemia–reperfusion injury, and the progression of non-alcoholic fatty liver disease to cirrhosis, fibrosis, and hepatocellular carcinoma. Of particular current interest are the steps involved in the activation of TRPM2 in hepatocytes following an increase in ROS, the downstream pathways activated by the resultant increase in intracellular Ca2+, and the chronology of these events. An apparent contradiction exists between these roles of TRPM2 and the role identified for ROS-activated TRPM2 in heart muscle and in some other cell types in promoting Ca2+-activated mitochondrial ATP synthesis and cell survival. Inhibition of TRPM2 by curcumin and other “natural” compounds offers an attractive strategy for inhibiting ROS-induced liver cell injury. In conclusion, while it has been established that ROS-initiated activation of TRPM2 contributes to both acute and chronic liver injury, considerable further research is needed to elucidate the mechanisms involved, and the conditions under which pharmacological inhibition of TRPM2 can be an effective clinical strategy to reduce ROS-initiated liver injury.


2021 ◽  
Vol 16 ◽  
Author(s):  
Ali Fathijouzdani ◽  
Rezvan Heidarimoghadam ◽  
Maryam Hazhirkamal ◽  
Akram Ranjbar

: The COVID-19 pandemic has caused serious concerns for people around the world. The COVID-19 is associated with respiratory failure, generation of reactive oxygen species (ROS), and the lack of antioxidants among patients. Specified ROS levels have an essential role as an adjuster of immunological responses and virus cleaners. Still, excessive ROS will oxidize membrane lipids and cellular proteins and quickly destroy virus-infected cells. It can also adversely damage normal cells in the lungs and even the heart, resulting in multiple organ failures. Given the above, a highly potent antioxidant therapy can be offered to reduce cardiac loss due to COVID-19. In modern medicine, nanoparticles containing antioxidants can be used as a high-performance therapy in reducing oxidative stress in the prevention and treatment of infectious diseases. It can provide a free and interactive tool to determine whether antioxidants & nanoantioxidants can be administered for COVID-19. More research and studies are needed to investigate and make definitive opinions about their medicinal uses.


Nanomedicine ◽  
2021 ◽  
Author(s):  
Muktashree Saha ◽  
Anil P  Bidkar ◽  
Siddhartha S  Ghosh

Aim: The primary aim of this study was to develop biomimetic nanocarriers for specific homologous targeting of the anticancer drugs ammonium pyrrolidine dithiocarbamate (PDTC) and doxorubicin. Methods: Membranous nanovesicles were synthesized from a breast cancer cell line (MCF7) by syringe extrusion process and were loaded with PDTC and doxorubicin. Besides their abilities for self-homing, the drug loaded nanovesicles showed anti-cell proliferative effects via the generation of reactive oxygen species. Results: The nanovesicles demonstrated efficient internalization via homologous targeting. Delivery of PDTC showed a higher killing effect for homologous cell targeting than other cell types. Experimental results demonstrated increased antiproliferative potency of PDTC, which induced apoptosis via reactive oxygen species generation. Conclusion: The developed membrane-derived nanocarrier is an attractive biocompatible system for ex vivo targeted drug delivery.


2021 ◽  
Author(s):  
Ye Zhao ◽  
Hai-Ming Feng ◽  
Xiao-Ping Wei ◽  
Wei-Jian Yan ◽  
Bin Li ◽  
...  

Abstract Reactive Oxygen Species (ROS) are present in high amount in patients with tumors, and these ROS can kill and destroy tumor cells. Thus, tumor cells upregulate ROS-related genes to protect themselves and reduce their destruction. Cancer cells already damaged by ROS can be repaired by expressing DNA repair genes consequently promoting their proliferation. In this work, lung adenocarcinoma (LUAD) transcriptome data in the TCGA database was analyzed and samples were clustered into 5 ROS-related categories and 6 DNA repair categories. Survival analysis revealed a significant difference in patient survival between the two classification methods. In addition, the samples corresponding to the two categories overlap, thus, the gene expression profile of the same sample with different categories and survival prognosis was further explored, and the connection between ROS-related genes and DNA repair genes was investigated. The interactive sample recombination classification was used, revealing that the patient's prognosis was worse when the ROS-related genes and DNA repair genes were expressed at the same time. The further research on the potential regulatory network of the two categories of genes and the correlation analysis revealed that ROS-related genes and DNA repair genes have a mutual regulatory relationship. The ROS-related genes NQO1, TXNRD1, and PRDX4 could establish links with other DNA repair genes through the DNA repair gene NEIL3, thereby increasing the growth of tumor cells and balancing the level of ROS, leading to tumor cell death and constant damage to the tumor cell repair system, thus prolonging patient survival. Thus, targeting ROS-related genes and DNA repair genes might be a promising strategy in the treatment of LUAD. Finally, a survival prognostic model of ROS-related genes and DNA repair genes was established (TERT, PRKDC, PTTG1, SMUG1, TXNRD1, CAT, H2AFX and PFKP), the risk score might be used as an independent prognostic factor in LUAD patients.


2017 ◽  
Vol 313 (6) ◽  
pp. R646-R653 ◽  
Author(s):  
Mohamad Assi

The large doses of vitamins C and E and β-carotene used to reduce reactive oxygen species (ROS) production and oxidative damages in cancerous tissue have produced disappointing and contradictory results. This therapeutic conundrum was attributed to the double-faced role of ROS, notably, their ability to induce either proliferation or apoptosis of cancer cells. However, for a ROS-inhibitory approach to be effective, it must target ROS when they induce proliferation rather than apoptosis. On the basis of recent advances in redox biology, this review underlined a differential regulation of prooxidant and antioxidant system, respective to the stage of cancer. At early precancerous and neoplastic stages, antioxidant activity decreases and ROS appear to promote cancer initiation via inducing oxidative damage and base pair substitution mutations in prooncogenes and tumor suppressor genes, such as RAS and TP53, respectively. Whereas in late stages of cancer progression, tumor cells escape apoptosis by producing high levels of intracellular antioxidants, like NADPH and GSH, via the pentose phosphate pathway to buffer the excessive production of ROS and related intratumor oxidative injuries. Therefore, antioxidants should be prohibited in patients with advanced stages of cancer and/or undergoing anticancer therapies. Interestingly, the biochemical and biophysical properties of some polyphenols allow them to selectively recognize tumor cells. This characteristic was exploited to design and deliver nanoparticles coated with low doses of polyphenols and containing chemotherapeutic drugs into tumor-bearing animals. First results are encouraging, which may revolutionize the conventional use of antioxidants in cancer.


Sign in / Sign up

Export Citation Format

Share Document