Abstract: Objective To investigate the effects of spermidine （SPD） on the proliferation, migration, invasion and apoptosis of colon cancer cells and the change of the sensitivity of HCT15 and SW620 to 5-Fu. Methods CCK-8, clonal formation assay, transwell migration and invasion assay, flow cytometry used to detect apoptosis, and subcutaneous tumor transplantation experiments in nude mice were performed to investigate the effects of SPD on the proliferation, migration and invasion ability and apoptosis of HCT15 and SW620 cells（KRAS mutant）, and the changes of the sensitivity of HCT15 and SW620 to 5-Fu. Results The IC₅₀ of HCT15 treated by SPD was 15.75±1.55 μM, and that of SW620 treated by SPD was 7.11±0.37 μM. The IC₅₀ of HT29 treated by SPD was 76.17±10.02 μM, and that of SW48 treated by SPD was 64.40±5.61 μM. The number of clones formed in HCT15 and SW620 treated by SPD at 5 μM was lower than that in control group, and it was not found that the number of cell clones formed by SPD treatment of HT29 and SW48 was less than that of control group. The number of HCT15 and SW620 cells passing through transwell cells after SPD treatment was significantly reduced compared with the control group. The apoptosis rates of HCT15 and SW620 treated with SPD at 20 μM were higher than those of the control group. Combined SPD and 5-Fu treatment of HCT15 and SW620 cells had lower IC₅₀ than 5-Fu treatment of HCT15 and SW620 cells alone. Treatment of HCT15 and SW620 cells with a combination of 5 μM SPD and 5 μM 5-Fu resulted in fewer cell clones than treatment of HCT15 and SW620 cells with 5-Fu alone. The apoptosis rates of HCT15 and SW620 cells treated with 1 μM SPD combined with 5 μM 5-Fu were higher than that treated with 5-Fu alone. Subcutaneous tumor transplantation in nude mice showed that the tumor volume of SPD treatment group was smaller than that of placebo group, and the tumor volume of SPD combined with 5-Fu treatment group was smaller than that of 5-Fu treatment group alone.ALT, AST and Cr levels were not found to be higher in the treatment group than in the placebo group. Conclusion SPD can inhibit the proliferation, migration and invasion of HCT15 and SW620 cells, promote the apoptosis of HCT15 and SW620 cells, enhance the sensitivity of HCT15 and SW620 to 5-Fu, inhibit the growth of subcutaneous transplantation tumors of SW620 and enhance the anti-tumor effect of 5-Fu, which has certain safety.

Key words: spermidine, colon cancer, anti-tumor, 5-Fu

摘要： 目的 探讨亚精胺（SPD）对结肠癌细胞增殖、迁移、侵袭、凋亡的影响和对5-Fu敏感性的影响。方法 采用CCK-8实验、克隆形成实验、Transwell迁移侵袭、流式细胞技术检测细胞凋亡实验、裸鼠皮下移植瘤实验研究SPD对HCT15和SW620（KRAS突变型）细胞增殖能力、迁移和侵袭能力、细胞凋亡的影响和HCT15和SW620对5-Fu敏感性的变化。结果 体外实验证明SPD处理HCT15和SW620的IC₅₀分别为15.75±1.55 μM和7.11±0.37 μM,处理HT29 和SW48（KRAS野生型）的IC₅₀分别为76.17±10.02 μM和64.40±5.61 μM;5 μM的SPD处理的HCT15和SW620形成的细胞克隆数量较对照组减少,尚未发现SPD处理HT29 和SW48形成的细胞克隆数量较对照组减少;1 μM的SPD处理后的HCT15和SW620细胞穿过Transwell小室的数量较对照组显著减少;20 μM的SPD处理 HCT15和SW620的凋亡率均高于对照组。联合使用SPD和5-Fu处理HCT15和SW620比单独使用5-Fu处理HCT15和SW620细胞的IC50更低;联合使用5 μM的SPD和5 μM的5-Fu处理HCT15和SW620比单独使用5-Fu处理HCT15和SW620细胞形成的细胞克隆数量更少;1 μM的SPD联合5 μM的5-Fu处理HCT15和SW620比单独使用5-Fu处理肿瘤细胞后的细胞凋亡率更高;裸鼠皮下移植瘤实验证明SPD处理组的肿瘤体积比安慰剂组的肿瘤体积更小,SPD联合5-Fu处理组的肿瘤体积比单独使用5-Fu处理组的肿瘤体积更小;尚未发现处理组的ALT,AST和Cr水平高于安慰剂组。结论 SPD抑制KRAS突变的HCT15和SW620细胞的增殖、迁移、侵袭能力,促进HCT15和SW620细胞凋亡,增强HCT15和SW620对5-Fu敏感性,抑制SW620皮下移植瘤生长并增强5-Fu的抗肿瘤作用,具有一定的安全性。

关键词: 亚精胺, 结肠癌, 抗肿瘤, 5-Fu