Biology:Bystander effect (radiobiology)
The radiation-induced bystander effect (bystander effect) is the phenomenon in which unirradiated cells exhibit irradiated effects as a result of signals received from nearby irradiated cells. In November 1992, Hatsumi Nagasawa and John B. Little first reported this radiobiological phenomenon.[1]
Effect
There is evidence that targeted cytoplasmic irradiation results in mutation in the nucleus of the hit cells.[2][3] Cells that are not directly hit by an alpha particle, but are in the vicinity of one that is hit, also contribute to the genotoxic response of the cell population.[4][5] Similarly, when cells are irradiated, and the medium is transferred to unirradiated cells, these unirradiated cells show bystander responses when assayed for clonogenic survival and oncogenic transformation.[6][7] This is also attributed to the bystander effect.
Demonstration
The demonstration of a bystander effect in 3D human tissues[8] and, more recently, in whole organisms[9] have clear implication of the potential relevance of the non-targeted response to human health.
Consequences
This effect may also contribute to the final biological consequences of exposure to low doses of radiation.[10][11] However, there is currently insufficient evidence to suggest that the bystander effect promotes carcinogenesis in humans at low doses.[12]
Notes
Note that the bystander effect is not the same as the abscopal effect. The abscopal effect is a phenomenon where the response to radiation is seen in an organ/site distant to the irradiated organ/area, that is, the responding cells are not juxtaposed with the irradiated cells. T-cells and dendritic cells have been implicated to be part of the mechanism.[13]
In suicide gene therapy, the "bystander effect" is the ability of the transfected cells to transfer death signals to neighboring tumor cells.[14]
References
- ↑ Nagasawa, H; Little, J. B. (1992). "Induction of sister chromatid exchanges by extremely low doses of alpha-particles". Cancer Research 52 (22): 6394–6. PMID 1423287.
- ↑ "Targeted cytoplasmic irradiation with alpha particles induces mutations in mammalian cells". Proceedings of the National Academy of Sciences of the United States of America 96 (9): 4959–64. April 1999. doi:10.1073/pnas.96.9.4959. PMID 10220401. Bibcode: 1999PNAS...96.4959W.
- ↑ "The radiation-induced bystander effect: evidence and significance". Human & Experimental Toxicology 23 (2): 61–5. February 2004. doi:10.1191/0960327104ht418oa. PMID 15070061. https://journals.sagepub.com/doi/10.1191/0960327104ht418oa.
- ↑ "Induction of a bystander mutagenic effect of alpha particles in mammalian cells". Proc. Natl. Acad. Sci. U.S.A. 97 (5): 2099–104. February 2000. doi:10.1073/pnas.030420797. PMID 10681418. Bibcode: 2000PNAS...97.2099Z.
- ↑ "Studies of bystander effects in human fibroblasts using a charged particle microbeam". International Journal of Radiation Biology 74 (6): 793–8. December 1998. doi:10.1080/095530098141087. PMID 9881726.
- ↑ "The bystander response in C3H 10T1/2 cells: the influence of cell-to-cell contact". Radiat. Res. 161 (4): 397–401. April 2004. doi:10.1667/rr3137. PMID 15038773. Bibcode: 2004RadR..161..397M.
- ↑ "Bystander effect and adaptive response in C3H 10T(1/2) cells". Int. J. Radiat. Biol. 80 (7): 465–72. July 2004. doi:10.1080/09553000410001725116. PMID 15360084.
- ↑ "DNA double-strand breaks form in bystander cells after microbeam irradiation of three-dimensional human tissue models". Cancer Res. 67 (9): 4295–302. May 2007. doi:10.1158/0008-5472.CAN-06-4442. PMID 17483342.
- ↑ "Microbeam irradiation of the C. elegans nematode". Journal of Radiation Research 50 Suppl A: A49–54. March 2009. doi:10.1269/jrr.08132s. PMID 19346684. Bibcode: 2009JRadR..50A..49B.
- ↑ "Oncogenic bystander radiation effects in Patched heterozygous mouse cerebellum". Proceedings of the National Academy of Sciences 105 (34): 12445–50. August 2008. doi:10.1073/pnas.0804186105. PMID 18711141. Bibcode: 2008PNAS..10512445M.
- ↑ "[Radiation-induced bystander effect: the important part of ionizing radiation response. Potential clinical implications]". Postepy Higieny i Medycyny Doswiadczalnej 63: 377–88. 2009. PMID 19724078.
- ↑ Blyth, Benjamin J.; Pamela J. Sykes (2011). "Radiation-Induced Bystander Effects: What Are They, and How Relevant Are They to Human Radiation Exposures?". Radiation Research 176 (2): 139–157. doi:10.1667/RR2548.1. ISSN 0033-7587. PMID 21631286. Bibcode: 2011RadR..176..139B. http://lowdose.energy.gov/radiation_bystandereffects.aspx.
- ↑ "Ionizing radiation inhibition of distant untreated tumors (abscopal effect) is immune mediated". International Journal of Radiation Oncology, Biology, Physics 58 (3): 862–70. March 2004. doi:10.1016/j.ijrobp.2003.09.012. PMID 14967443.
- ↑ Karjoo, Z.; Chen, X.; Hatefi, A. (2015). "Progress and problems with the use of suicide genes for targeted cancer therapy". Advanced Drug Delivery Reviews 99 (Pt A): 113–28. doi:10.1016/j.addr.2015.05.009. PMID 26004498.
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