Despite radiotherapy is an effective regimen in cancer treatment, resistance to tumor therapy still is a major challenge to radiotherapy and results in cancer recurrence and metastasis. Then the sensitization of tumor cells to ionizing radiation (IR) would be beneficial in cancer treatment. The aim of this study was to evaluate the synergistic effect of mefenamic acid (MEF) on colon cancer cell (HT-29) exposure to IR. HT-29 cells were treated with MEF and then exposed to IR. The synergistic effect of MEF is evaluated by clonogenic assay and flow cytometry. The productions of reactive oxygen species (ROS) were determined in irradiated and treated cells with MEF. The findings of this study showed that MEF had anti-cancer effect on colon cancer cell line and it increased the apoptosis in irradiated HT-29 cells. Also MEF reduced the number of cell colonies when HT-29 cells pre-treated with MEF and irradiated. MEF increased ROS production in irradiated cells. This additive effect of MEF with IR in killing of HT-29 cell was observed at low (10 μM) and medium (100 μM) concentrations of MEF. The present study demonstrates that MEF to be an additive effect on apoptosis and cell death induced by IR in colon cancer cells.

中文翻译：

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甲芬那酸与电离辐射在结肠癌中的协同作用。

尽管放射疗法是癌症治疗的有效方案，但是对肿瘤疗法的抵抗仍然是放射疗法的主要挑战，并导致癌症复发和转移。然后，肿瘤细胞对电离辐射（IR）的敏化对癌症治疗将是有益的。这项研究的目的是评估甲芬那酸（MEF）对结肠癌细胞（HT-29）暴露于IR的协同作用。HT-29细胞用MEF处理，然后暴露于IR。通过克隆形成测定和流式细胞术评估MEF的协同作用。在用MEF辐照和处理的细胞中测定活性氧（ROS）的产生。这项研究的结果表明，MEF对结肠癌细胞系具有抗癌作用，并能增加照射的HT-29细胞的凋亡。当用MEF预处理并照射HT-29细胞时，MEF也减少了细胞集落的数量。MEF增加了受辐照细胞中ROS的产生。在低浓度（10μM）和中等浓度（100μM）的MEF中观察到了MEF与IR的杀伤HT-29细胞的这种加和作用。本研究表明MEF对结肠癌细胞中IR诱导的凋亡和细胞死亡具有累加作用。