肿瘤细胞化疗后^(99)Tc^m-DTPA-DG摄取研究

Study on the uptake of ^(99)Tc^m-DTPA-DG by tumor cells after chemotherapy

目的探讨99Tcm标记二乙三胺五乙酸葡糖胺(99Tcm-DTPA-DG)在恶性肿瘤化疗早期疗效监测中的应用价值。方法将体外培养肺癌细胞A549、结肠癌细胞HT-29和乳腺癌细胞MCF-7各分为加入化疗药物的化疗组和不加化疗药物的阴性对照组,所选化疗药物分别为顺铂、5-氟尿嘧啶、紫杉醇。化疗药作用6h后,荧光倒置显微镜下观察各化疗组和对照组细胞形态变化,并行磷脂结合蛋白V(AV)/碘化丙啶(PI)双标记染色,采用流式细胞仪检测各组细胞的凋亡率,化疗药作用4h后,各化疗组和对照组分别加入37MBq/L的99Tcm-DTPA-DG各0.1ml,反应2h,用γ测量仪检测99Tcm-DTPA-DG摄取率。结果经单用化疗药作用后,3种肿瘤细胞在荧光倒置显微镜下观察均可见凋亡小体形成。流式细胞仪检测也均出现凋亡峰。化疗组和对照组的凋亡率肺癌细胞分别为43.60%±2.82%和1.21%±0.15%,结肠癌细胞分别为32.42%±2.02%和2.04%±0.23%,乳腺癌细胞分别为52.33%±2.72%和1.31%±0.10%,差异均有统计学意义(P<0.01)。γ测量仪检测显示3种肿瘤细胞化疗组99Tcm-DTPA-DG摄取率均明显低于对照组(肺癌细胞分别为0.44%±0.02%、0.79%±0.12%,结肠癌细胞分别为0.35%±0.13%、0.58%±0.23%,乳腺癌细胞分别为0.28%±0.05%、0.65%±0.18%,均P<0.01)。结论99Tcm-DTPA-DG是一种可望用于肿瘤化疗效果早期评估的靶向分子显像剂。

Objective To evaluate the value of 99Tcm-DTPA-DG in monitoring the early response of malignant tumors to chemotherapy. Methods In vitro cultured lung cancer cells A549, colon carcinoma cells HT-29, and breast cancer cells MCF-7 were divided into chemotherapeutic and control groups respectively. The chemotherapeutic drugs used in this study included cisplatin, 5-fluoro-2, 4 (1H, 3H) pyrimidinedione (5-Fu), and paclitaxel. After being treated with the drugs for 6 hours, morphologic changes of the cells were observed under an inverted fluorescence microscope. Then, the cells were double-stained with Annexin V and propidium iodide, and the rate of apoptosis in each group was assessed by flow cytometry. In another experiment, 4 hours after the chemotherapy, 99Tcm-DTPA-DG (0.1 ml, 37 MBq/L) was added to each group, and then the rate of uptake of 99Tcm-DTPA-DG was determined using γ counter 2 hours later. Results In all the chemotherapeutic groups, inverted fluorescent microscope showed apoptotic bodies, and flow cytometry found apoptotic peaks. In the lung cancer cells, the apoptotic rate of the chemotherapeutic and control groups were 43.60% ± 2.82% and 1.21% ± 0.15%, and those in the colon cancer cells and breast cancer cells were 32.42% ± 2.02% and 2.04% ± 0.23%, and 52.33% ± 2.72% and 1.31% ± 0.10%, respectively. The differences between the chemotherapeutic groups and the controls were all significant (P < 0.01). And the uptake rates of 99Tcm-DTPA-DG by the three tumor cells in the chemotherapeutic groups were all significantly lower than those in the controls. (0.44% ± 0.02% vs 0.79% ± 0.12% in the lung cancer cells, 0.35% ± 0.13% vs 0.58% ± 0.23% in the colon cancer cells, and 0.28% ± 0.05% vs 0.65% ± 0.18% in the breast cancer cells, P < 0.01). Conclusions 99Tcm-DTPA-DG is a targeted molecular imaging agent, promising in the evaluation of early response of tumors to chemotherapy.