Radiotherapy is a cancer treatment protocol which delivers high dose of ionizing radiation (IR) to tumor. Tumor resistance and side effects induced by IR still are the major challenges in radiotherapy. The purpose of this study was to evaluate the synergistic killing effect of fluoxetine (FL) with IR on glioma cancer cell (U-87 MG), as well as radioprotective effect of FL against cellular toxicity induced by IR on non-malignant human fibroblast cell (HFFF2). Firstly, the inhibitory effects of FL on cell proliferations were evaluated in U-87 MG and HFFF2 cells. The clonogenic and MTT assays were used to evaluate the radiosensitivity and radioprotective effects of FL on cancer and non-malignant cells. The frequencies of apoptotic cells were evaluated by flow cytometry on both cancer and normal cells. Results showed that FL exhibited anti-cancer effect on glioma cells, while cellular toxicity was low in HFFF2 cells treated with FL. FL decreased the viable colonies and enhanced apoptotic cells when U-87 cells were treated with FL prior irradiation. For comparison, FL exhibited radioprotective effect through increasing cellular proliferation rate and reducing apoptosis in HFFF2 cells against IR. The results showed that FL enhanced the IR-induced glioma cancer cell death and apoptosis, whereas it exhibited a radioprotective effect on normal fibroblast cells suggesting that FL administration may improve glioma radiotherapy.

中文翻译：

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氟西汀作为抗抑郁药可改善电离辐射治疗神经胶质瘤的效果。

放射疗法是一种癌症治疗方案，可向肿瘤输送高剂量的电离辐射（IR）。IR引起的肿瘤抵抗和副作用仍然是放疗中的主要挑战。这项研究的目的是评估氟西汀（FL）与IR对神经胶质瘤癌细胞（U-87 MG）的协同杀伤作用，以及FL对IR诱导的对非恶性人类成纤维细胞的细胞毒性的放射防护作用（HFFF2）。首先，在U-87 MG和HFFF2细胞中评估了FL对细胞增殖的抑制作用。克隆形成和MTT分析用于评估FL对癌症和非恶性细胞的放射敏感性和放射防护作用。通过流式细胞术评估癌细胞和正常细胞的凋亡细胞频率。结果表明，FL对神经胶质瘤细胞具有抗癌作用，而经FL处理的HFFF2细胞的细胞毒性较低。当U-87细胞在照射前用FL处理后，FL降低了活菌落并增强了凋亡细胞。为了进行比较，FL通过增加细胞增殖速率和减少HFFF2细胞针对IR的凋亡表现出放射防护作用。结果表明，FL增强了IR诱导的神经胶质瘤癌细胞的死亡和细胞凋亡，而对正常的成纤维细胞则显示出放射防护作用，这表明FL的给药可以改善神经胶质瘤的放射治疗。FL通过增加细胞增殖速率和减少HFFF2细胞中针对IR的凋亡而显示出放射防护作用。结果表明，FL增强了IR诱导的神经胶质瘤癌细胞的死亡和细胞凋亡，而对正常的成纤维细胞则显示出放射防护作用，这表明FL的给药可以改善神经胶质瘤的放射治疗。FL通过增加细胞增殖速率和减少HFFF2细胞对IR的凋亡而显示出放射防护作用。结果表明，FL增强了IR诱导的神经胶质瘤癌细胞的死亡和细胞凋亡，而对正常的成纤维细胞则显示出放射防护作用，这表明FL的给药可以改善神经胶质瘤的放射治疗。