中文摘要：

目的研究羟基磷灰石纳米粒子（nano-HAP）对人肝癌BEL-7402细胞和结肠癌SW-480细胞生长及凋亡的影响。方法用羟基磷灰石纳米粒子以不同终浓度作用于这二株细胞。用噻唑蓝（MTT）比色法观察其对两株细胞的生长抑制，荧光显微镜、透射电镜、DNA琼脂糖凝胶电泳、流式细胞术（FCM）等方法从细胞凋亡的角度探讨其作用机制。结果羟基磷灰石纳米粒子对BEL07402和SW-480细胞的半数有效抑制浓度（IC50）值分别为29．28mg／L和36．66mg／L。50～100mg／L的纳米粒子处理48h后，癌细胞即可表现出细胞皱缩、核质浓缩、核碎裂以及凋亡小体形成等凋亡特征性形态改变。作用48h后，琼脂糖凝胶电泳观察到DNA“梯带”。流式细胞仪定量分析显示人肝癌、结肠癌细胞经0、50、100、200mg／L作用48h后的细胞凋亡率分别为2．23％、20．35％、29．34％、53．64％和3．57％、21．45％、37．10％、49．45％。结论羟基磷灰石纳米粒子对人肝癌BEL07402和结肠癌SW-480细胞有明显的生长抑制作用，诱导癌细胞凋亡可能是其主要作用机制．

英文摘要：

Objective To study the effect of hydroxyapatite （HAP） nanoparticles on growth and apoptosis of human hepatoma cell line BEL-7402 and colon carcinoma SW-480 in vitro. Methods The human hepatoma and colon carcinoma cells were treated with HAP nanoparticles at various concentrations. Growth suppression and apoptotic alterations were evaluated by MTT method, cytochemical staining （Hoechst 33258）, transmission electron microscopy, DNA agarose gel electrophoresis and flow cytometry （FCM）. Results HAP nanoparticles inhibited the growth of hepatoma and colon carcinoma cells in a dose-dependent manner, with IC50 values of 29.30 mg/L and 36.66 mg/L respectively. After being treated with 50-100 mg/L HAP nanoparticles for 48 h, the apoptosis of two cell lines was observed. After treatment for 48 h, DNA ladder of human hepatoma BEL-7402 with 150 mg/L HAP nanoparticles could be demonstrated on DNA electrophoresis, whereas colon carcinoma SW-480 with 100 mg/L. FCM analysis revealed hypodiploid peaks on histogram, the apoptotic rates of human hepatoma and colon carcinoma cell lines at concentrations of 0 mg/L, 50 mg/L, 100 mg/L, 200 mg/L were 2.23 %, 20.35 %, 29.34 %, 53.64% and 3.57%,21.45%,37.10%,49.45% respectively. Conclusion HAP nanoparticles could inhibit the growth of human hepatoma cell line BEL-7402 and colon carcinoma SW-480 obviously. Apoptotic induction may be the mainly antineoplastic mechanism.