scholarly journals Low-Dose Radiation Induces Adaptive Response in Normal Cells, but not in Tumor Cells: In vitro and in vivo Studies

2008 ◽  
Vol 49 (3) ◽  
pp. 219-230 ◽  
Author(s):  
Hongyu JIANG ◽  
Wei LI ◽  
Xiuyi LI ◽  
Lu CAI ◽  
Guanjun WANG
Author(s):  
Hamid Ghaznavi ◽  
Farideh Elahimanesh ◽  
Jamil Abdolmohammadi ◽  
Meysam Mirzaie ◽  
Sadegh Ghaderi

Abstract Background: The Coronavirus disease 2019 (COVID-19) is spreading rapidly throughout the world. Lung is the primary organ which the COVID-19 virus affects and leads to pneumonia, an acute respiratory distress syndrome. COVID-19 infects the lower respiratory system, and the lung’s response to this infection is recruiting macrophages and monocytes leading to inflammation, this response causes widespread damage to the lung’s airways. Aim: The purpose of this study is to review studies of using low-dose radiation as a treatment for the inflammation of the tissue and pneumonia resulting from COVID-19. These studies were compared with the risk of developing lung cancer during performed dose for the treatment of COVID-19 in radiation therapy. Materials and methods: Our study focused on in vitro, in vivo and clinical reports of using low-dose radiation for the treatment of inflammation, pneumonia and COVID-19. The risk of lung cancer resulting from suggested dose in these studies was also evaluated. Conclusion: From the review of articles, we have found that low-dose radiation can lead to improvement in inflammation in different line cells and animals; in addition, it has been effective in treating inflammation and pneumonia caused by COVID-19 in human up to 80%. Since suggested doses do not remarkably increase the lung cancer risk, low-dose radiation can be an adjuvant treatment for COVID-19 patients.


2009 ◽  
Vol 27 (15_suppl) ◽  
pp. e22113-e22113
Author(s):  
M. N. Jha ◽  
J. S. Bedford ◽  
S. Jha ◽  
K. Prasad

e22113 Background: It is estimated that low dose radiation can increase the risk of cancer as well as mutations. However, the interaction of low dose radiation with caffeine has not been adequately investigated. We investigated the effects of caffeine on low dose- gamma-radiation-induced chromosomal damage in human T leukemia cells (Jurket T-cells) and two normal human fibroblast cell lines (AG1522 and GM 2149). Method: Jurkat cells were maintained in RPMI 1640 medium and fibroblast in alpha-minimal essential medium (MEM) All cells were incubated at 37o C in a humidified atmosphere of 5% CO2 in air. Cells from the exponential phase were treated with 1 mg/ml caffeine ( control cells received same amount of solvent) and irradiated with low doses (3, 5, 10, 20 and 40 cGy,), using a 137 Cs-gamma radiation source. Colcemid at a concentration of 0.1 μg/ml was added to every flask. Cells were fixed in methanol: acetic acid solution and stained with Giemsa. 100 irradiated and un-irradiated metaphase- like cells were scored for chromatid-type aberrations. Results: Low dose gamma-radiation increased the levels of chromatid breaks(dose dependent) in both normal and cancer cells; however, cancer cells appeared to be more sensitive than the normal cells. Caffeine treatment markedly increased chromatid aberrations in Jurkat T-cells at all radiation doses but not in normal cells. Previously, we reported that caffeine eliminates gamma-ray-induced G2 delay in other human tumor cells but not normal cells (Jha, et.al., Radiat. Res. 157, 26–31, 2002). Conclusions: The mechanisms that may underlie this differential effect of caffeine in cancer and normal cells are unknown, but if one result of a G2 delay is to allow more time for chromosome breakage rejoining processes to occur, then elimination of this delay by caffeine in tumor cells but not normal cells might account for the difference. To the extent these observations are generally true for tumor vs normal cells, the differential sensitization could have an impact in improving the efficacy of radiation therapy. No significant financial relationships to disclose.


Author(s):  
Mingzhu Chen ◽  
Ziqi Wang ◽  
Weilong Suo ◽  
Zhirong Bao ◽  
Hong Quan

Higher doses of radiotherapy (RT) are associated with resistance induction, therefore highly selective and controllable radiosensitizers are urgently needed. To address this issue, we developed a FeGA-based injectable hydrogel system (FH) that can be used in combination with low-dose radiation. Our FH can deliver FeGA directly to the tumor site via intratumoral injection, where it is a reservoir-based system to conserve FeGA. The photothermal properties of FeGA steadily dissolve FH under laser irradiation, and, simultaneously, FeGA reacts with a large amount of H2O2 in the cell to produce OH (Fenton reaction) which is highly toxic to mitochondria, rendering the cell inactive and reducing radiotherapy resistance. In vivo and in vitro studies suggest that combining the FH and NIR irradiation with RT (2Gy) can significantly reduce tumor proliferation without side effects such as inflammation. To conclude, this is the first study to achieve combined chemodynamic therapy (CDT) and photothermal therapy (PTT) in situ treatment, and the best therapeutic effect can be obtained with a low-dose radiation combination, thus expanding the prospects of FeGA-based tumor therapy.


Dose-Response ◽  
2007 ◽  
Vol 5 (4) ◽  
pp. dose-response.0 ◽  
Author(s):  
Pamela J. Sykes ◽  
Tanya K. Day

Cancer results from multiple changes in gene expression that can occur both genetically and epigenetically. High doses of radiation can lead to mutations and cancer. At high doses the number of mutations caused by radiation is essentially linear with dose. Low dose radiation induced protective responses observed for cancer in vivo and cellular transformation in vitro would predict that hormetic responses would also be observed in mutation assays. Although there are a large number of different mutation assays available, very few are able to detect changes in mutation frequency in response to very low doses of DNA damaging agents. The easiest way to cope with this lack of data in the low dose range is to invoke a linear-no-threshold model for risk assessment. The reasons for the lack of data are discussed. In order to identify hormetic mutation responses, assays need to have a spontaneous frequency that is high enough to enable a reduction below spontaneous frequency to be detected in a feasible number of scored cells and also need to be able to identify both genetic and epigenetic changes. The pKZ1 chromosomal inversion assay fits the criteria for detecting hormetic responses to low dose radiation.


2019 ◽  
Vol 65 (5) ◽  
pp. 760-765
Author(s):  
Margarita Tyndyk ◽  
Irina Popovich ◽  
A. Malek ◽  
R. Samsonov ◽  
N. Germanov ◽  
...  

The paper presents the results of the research on the antitumor activity of a new drug - atomic clusters of silver (ACS), the colloidal solution of nanostructured silver bisilicate Ag6Si2O7 with particles size of 1-2 nm in deionized water. In vitro studies to evaluate the effect of various ACS concentrations in human tumor cells cultures (breast cancer, colon carcinoma and prostate cancer) were conducted. The highest antitumor activity of ACS was observed in dilutions from 2.7 mg/l to 5.1 mg/l, resulting in the death of tumor cells in all studied cell cultures. In vivo experiments on transplanted Ehrlich carcinoma model in mice consuming 0.75 mg/kg ACS with drinking water revealed significant inhibition of tumor growth since the 14th day of experiment (maximally by 52% on the 28th day, p < 0.05) in comparison with control. Subcutaneous injections of 2.5 mg/kg ACS inhibited Ehrlich's tumor growth on the 7th and 10th days of the experiment (p < 0.05) as compared to control.


Author(s):  
Maryam Muhammad Mailafiya ◽  
Mohamad Aris Mohd Moklas ◽  
Kabeer Abubakar ◽  
Abubakar Danmaigoro ◽  
Samaila Musa Chiroma ◽  
...  

Background: Cockle shell-derived calcium carbonate nanoparticles (CSCaCO3NP) are natural biogenic inorganic material that is used in drug delivery mainly as a bone-remodeling agent as well as a delivery agent for various therapeutics against bone diseases. Curcumin possess wide safety margin and yet puzzled with the problem of poor bioavailability due to insolubility. Propounding in vitro and in vivo studies on toxicity assessments of newly synthesized nanoparticles are ongoing to overcome some crucial challenges regarding their safety administration. Nanotoxicology has paved ways for concise test protocols to monitor sequential events with regards to possible toxicity of newly synthesized nanomaterials. The development of nanoparticle with no or less toxic effect has gained tremendous attentions. Objective: This study aimed at evaluating the in vitro cytotoxic effect of curcumin-loaded cockle shell-derived calcium carbonate nanoparticles (Cur-CSCaCO3NP) and assessing its biocompatibility on normal cells using standard techniques of WST’s assay. Method: Standard techniques of WST’s assay was used for the evaluation of the biocompatibility and cytotoxicity. Result: The result showed that CSCaCO3NP and Cur-CSCaCO3NP possess minimal toxicity and high biocompatibility on normal cells even at higher dose of 500 µg/ml and 40 µg/ml respectively. Conclusion: CSCaCO3NP can be termed an excellent non-toxic nanocarrier for curcumin delivery. Hence, curcumin loaded cockle shell derived calcium carbonate nanoparticles (Cur-CSCaCO3NP) could further be assessed for various in vivo and in vitro therapeutic applications against various bone related ailments.


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