Preliminary Results of the Effects of Localized High-Dose Radiotherapy Combined with Total Body Low-Dose Irradiation on Tumor Growth and Stimulating the Immune System in Tumor-Bearing Mice

• Published in: Journal of biomedical physics and engineering 2023-08, Vol.13 (4), p.323-332
• Main Authors: Bahrayni Toosi, Mohammad Taghi, Kasiri, Afsaneh, Torabinejad, Sepehr, Soleymanifard, Shokouhozaman, Sankian, Mojtaba, Aledavood, Seyed Amir, Hosseini Shamili, Fazileh, Lavi, Fahime
• Format: Article
• Language: English
• Subjects: ifn-γ; immune system; Original; radiotherapy; whole-body irradiation
• ISSN: 2251-7200; 2251-7200
• DOI: 10.31661/jbpe.v0i0.2009-1179

BackgroundThe immune system plays an extensive role in eliminating tumor cells. On the other hand, low-dose irradiation stimulates the immune system. ObjectiveThe present study aimed to investigate the therapeutic outcomes of localized high-dose radiotherapy (LH) alone and combined with total body low-dose irradiation (TB). Material and MethodsIn this experimental study, B16F0 tumor cells were injected into the right flank of C57JL/6 mice. The mice were treated with LH alone (13 Gy X-rays to the tumor surface) (LH group) or combined with TB (85 mGy X-rays at the skin) (TB+LH group). Then the tumor volume, the mice's lifespan, the number of lymphocytes extracted from the spleen, and interferon gamma (IFN-γ) production were measured. ResultsReduced number of lymphocytes, compared to non-irradiated mice (control group), was observed in LH and TB+LH groups. However, the identical number of cultured lymphocytes produced a higher level of IFN-γ in irradiated groups. Comparing the irradiated groups, the number of lymphocytes and their IFN-γ production, tumor growth control, and the mice's lifespan were statistically higher in TB+LH group. ConclusionObserving a higher level of IFN-γ in TB+LH group compared to LH group indicates that low-dose radiation enhanced the stimulating effects of high-dose radiation on the immune system. It caused the mice in TB+LH group to have a more prolonged lifespan and a lower tumor growth rate. Therefore, it is worth our attention for future studies to investigate whether total body low-dose irradiation can be utilized before radiotherapy to enhance its efficiency.