右旋糖酐-磁性层状复合氢氧化物-氟尿嘧啶给药系统对结肠癌细胞的增殖抑制与诱导凋亡作用

Proliferation Inhibition and Apoptosis Induction Effect of Dextran-Magnetic Layered Double Hydroxide-Fluorouracil Drug Delivery System on Human Colon Cancer Cells SW480

目的探讨右旋糖酐-磁性层状复合氢氧化物-氟尿嘧啶给药系统对体外培养结肠癌SW480细胞增殖的抑制效果与诱导凋亡作用。方法采用MTT法检测各浓度右旋糖酐-磁性层状复合氢氧化物-氟尿嘧啶及所涉及各级超分子对结肠癌细胞的增殖抑制率;光镜显微、Giemsa染色表征细胞的形态变化;流式细胞术检测药物干预引起的SW480细胞凋亡率;DNA ladder分析凋亡细胞核的裂解情况。结果磁性层状复合氢氧化物、磁性层状复合氢氧化物-氟尿嘧啶、右旋糖酐-磁性层状复合氢氧化物-氟尿嘧啶3级超分子对SW480细胞干预24 h的IC50依次为44.83(25.74,48.78)μg·mL-1、15.16(13.78,16.66)μg·mL-1和13.33(11.03,15.13)μg·mL-1;不同浓度5-Fu及相等剂量的磁性层状复合氢氧化物、磁性层状复合氢氧化物-氟尿嘧啶、右旋糖酐-磁性层状复合氢氧化物-氟尿嘧啶对结肠癌SW480细胞分别干预24、48、72 h,细胞的增殖抑制率按磁性层状复合氢氧化物<<氟尿嘧啶<磁性层状复合氢氧化物-氟尿嘧啶<右旋糖酐-磁性层状复合氢氧化物-氟尿嘧啶升高,作用效果与剂量及时间有依赖关系;与原药相比,右旋糖酐-磁性层状复合氢氧化物-氟尿嘧啶对SW480细胞的增殖抑制率及早期凋亡率差异显著,能引起细胞核内染色质凝集、细胞解体。结论磁性层状复合氢氧化物细胞毒性低,能用作药物载体;磁性层状复合氢氧化物与氟尿嘧啶的2～3级超分子组装,具有相对原药更高的药物传输效率、能有效发挥抗肿瘤药物对SW480细胞的抑制与诱导凋亡作用。

OBJECTIVE To explore the proliferation inhibition and apoptosis induction effect of dextran - magnetic layered double hydroxide - fluorouracil（DMF） drug delivery system on colon cancer cell SW480 euhivated in vitro. METHODS MqT experiment was used to detect the cell proliferation inhibition rates of DET-MLDH-FU, MLDH-FU and MLDH supra-molecules at various concen- trations. Light microscopy and Giemsa dyeing methods were applied for characterizing the shape change of the apoptotic cells. Flow cy- tometric analysis was employed to test the apoptosis rates of SW480 cells treated with different drugs for 24 h. DNA ladder method was used to analyze nuclei breakup of the apoptosis cells. RESULTS The ICs0 of MLDH, MLDH-FU and DMF three-level supra-mole- cules for SW480 cells were 44. 83 （25.74, 48.78 ）, 15. 16 （ 13.78, 16. 66） and 13.33 （ 11.03, 15. 13 ） μg · mL-1, respectively. The proliferation of colon cancer cells SW480 was obviously restrained after being treated with 5-Fu and equivalent MLDH, MLDH-FU and DMF of different concentrations for 24, 48 and 72 h , respectively. The result revealed that the inhibition rates increased in the se- quence of MLDH 〈 〈 FU 〈 MLDH-FU 〈 DMF and showed a dose-effect relationship and time dependence. Compared with FU, DMF caused significantly different proliferation inhibition and early apoptosis of SW480 ceils. In addition, DMF also caused agglutination of intra-nuclear chromatin and disintegration of cells. CONCLUSION With low cytotoxicity, MLDH can be used as a drug carrier. Compared with FU, 2 - 3 grades supra-molecular assembly of MLDH-FU and DET-MLDH-FU have relatively higher transmission effi- ciency and produces significant proliferation inhibition and apoptosis induction effect for SW480 cells.