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Postmenopausal patients with breast cancer have two options for adjuvant endocrine therapy, tamoxifen and aromatase inhibitors (AIs) as well as radiotherapy (RT) and chemotherapy. However, there is limited data regarding the optimal sequencing of RT and tamoxifen/AIs. Thus, we aimed to evaluate the effects of tamoxifen and AIs on radiation-induced cardiotoxicity. Eighty ovariectomized rats were divided into eight groups (G). G1 was defined as a control group; G2, G3, G4, and G5 were RT, tamoxifen, anastrozle, and letrozole groups, respectively; G6, G7, and G8 were RT plus tamoxifen, anastrozle, and letrozole groups, respectively. Drugs were started 1 week before RT and continued until the animals were killed 16 weeks after RT. The heart tissues were then dissected and examined with light microscopy to determine endocardial thickness and cardiac fibrosis. The endocardial thickness scores of both RT alone and the tamoxifen groups as well as the cardiac fibrosis score of RT alone were higher than that the control group (p < 0.05 for all). There was no difference in the endocardial thickness and cardiac fibrosis scores of the RT-only group and the RT plus hormonotherapy groups (p > 0.05 for all). Concurrent administration of RT and hormonal therapy with either tamoxifen or AIs did not further amplify radiation-induced cardiac toxicity. This issue warrants further study. [ABSTRACT FROM AUTHOR]

To evaluate effects of halofuginone (H) on radiation-induced lung injury (RILI), 60 rats were divided into six groups: Group (G) 1 control, G2 radiotherapy (RT) only, G3 and G4 2. 5 and 5 μg H and G5 and G6 RT + 2.5 and 5 μg H groups, respectively. A single dose of 12 Gy RT was given to both lungs. H was applied intraperitoneally with daily doses, until animals were killed at 6 and 16 weeks after RT. At 6th and 16th weeks of RT, five rats from each group were killed. Lung tissues were dissected for light and electron microscopy. Chronic inflammation, fibrosis and transforming growth factor-beta (TGF)-β scores of all study groups were significantly different at 6th and 16th week (p < 0.001). Chronic inflammation, fibrosis and TGF-β scores of G2 were higher than G5 and G6 at 6th and 16th weeks of RT. At 16th week, fibrosis and TGF-β scores of G5 were higher than G6 (p = 0.040 and 0.028, respectively). Electron microscopical findings also supported these results. Therefore, H may ameliorate RILI. The effect of the H was more prominent at higher dose and after long-term follow-up. These findings should be clarified with further studies. [ABSTRACT FROM AUTHOR]