rhTRAIL对小鼠乳腺癌的抑制作用

目的:探讨重组人肿瘤坏死因子相关凋亡诱导配体（rhTRAIL）对小鼠乳腺癌的抑制作用。 方法: 将5×109cells/L对数生长期的小鼠乳腺癌细胞D2F2接种于BALB/c小鼠右上肢皮下，每只接种0.2 mL（1×106个细胞），随机分为5组。空白对照组：PBS 0.2 mL；rhTRAIL低、中、高剂量组：剂量分别为2.5 mg/kg、5.0 mg/kg、10.0 mg/kg；阳性药物组：环磷酰胺30.0 mg/kg。各组均采用腹腔注射，每天1次，共15 d。每天小鼠称重记录，每3 d观察肿瘤的生长情况并用游标卡尺测定肿瘤的长径和短径，计算肿瘤体积和抑瘤率。停药后处死小鼠，取瘤进行肿瘤组织光镜和电镜观察。同时流式细胞仪检测经不同浓度rhTRAIL作用后细胞凋亡及细胞周期变化。 结果: 与空白对照组相比，rhTRAIL 2.5 mg/kg、5.0 mg/kg、10.0 mg/kg（低、中、高）剂量组的肿瘤重量和体积明显低于空白对照组（P＜0.01），且rhTRAIL低、中、高剂量组的肿瘤重量和体积随药物浓度的增加而降低（P＜0.01）。rhTRAIL 2.5 mg/kg、5.0 mg/kg、10.0 mg/kg（低、中、高）剂量组肿瘤细胞既有坏死也有凋亡样改变，肿瘤组织破坏面积大，很多区域看不到正常的肿瘤细胞，可见凋亡小体。流式细胞仪检测结果显示rhTRAIL蛋白可诱导D2F2细胞凋亡，0.25 mg/L、0.5 mg/L、1.0 mg/L组细胞凋亡率分别为7.56%、21.37%、27.16%，凋亡率随剂量增大而升高（P＜0.05 )。 结论: rhTRAIL可诱导小鼠乳腺癌细胞D2F2凋亡并有大量的乳腺癌细胞坏死，rhTRAIL对小鼠乳腺癌细胞D2F2具有抑制作用。

The inhibitory action of rhTRAIL on mouse breast carcinoma

AIM:To explore the inhibitory action of recombinant human tumor necrosis factor-related apoptosis-inducing ligand(rhTRAIL) on mouse breast cancer.METHODS:Each mouse was inoculated 0.2 mL (1×106) D2F2 cells subcutaneously in the right lower limb and they were divided into five groups randomly.The control group was infused PBS 0.2 mL, while the low-dose, medium, high groups received purified rhTRAIL 2.5 mg/kg, 5.0 mg/kg, 10.0 mg/kg, respectively, the positive group was administered cyclophosphamide 30.0 mg/kg.Every group was operated by peritoneal injection once a day for fifteen days.The mice were weighed every day.The growth state was viewed and the size of the tumor was measured every 3 d to calculate the tumor volume and tumor suppression rate.All mice were killed after 15 d.The pathologic changes of the tumor were observed under light-microscopy and electronic microscopy.The cell cycle and apoptosis index of D2F2 cells were analyzed by flow cytometry.RESULTS: The body weight and tumor volume in low-dose, medium, high groups were lower than those in control group and the restriction effect was more significant than that in the control group (P<0.01).The body weight and tumor volume in low-dose, medium, high groups decreased with the increase in rhTRAIL concentration.The difference was significant (P<0.01).Both apoptosis and necrosis of tumor cells were observed in low-dose, medium, high groups.The area of cell apoptosis was large and most area didnt have tumor cells but only apoptotic bodise.The results of flow cytometry showed that rhTRAIL induced the apoptosis of D2F2 cells, and the apoptosis rates were 7.56 %, 21.37 %, 27.16 % respectively when rhTRAIL doses were 0.25 mg/L, 0.5 mg/L, 1.0 mg/L.Significant differences among three groups were observed (P<0.05).CONCLUSION:rhTRAIL induces apoptosis in mouse breast cancer cells and even the necrosis of tumor cells.rhTRAIL has significant effect on inhibiting the growth of D2F2 cells.