纳米氧化铈对人乳腺癌Bcap-37细胞裸鼠移植瘤的生长抑制作用

Inhibitory effect of cerium oxide nanoparticles on growth of human breast carcinoma Bcap-37 cell xenografts in nude mice

目的探讨纳米氧化铈(nm-Ce O2)对人乳腺癌Bcap-37细胞裸鼠移植瘤的生长抑制作用。方法建立人乳腺癌Bcap-37细胞裸鼠皮下移植瘤模型,随机分为阴性对照组(等体积双蒸水)、阳性药组[九州虫草2 000 mg/(kg·次)]、nm-Ce O2高、中、低剂量组[300、100、33.33 mg/(kg·次)],共5组,各组荷瘤裸鼠均经口灌胃给药,每天1次,共17 d,观察各组裸鼠移植瘤生长情况,计算肿瘤体积(VT)、肿瘤生长抑制率,称量肿瘤重量,观察移植瘤组织病理变化,采用脱氧核糖核苷酸末端转移酶介导的缺口末端标记(terminal dexynucleotidyl transferase mediated d UTP nick end la beling,TUNEL)法检测移植瘤细胞凋亡率。结果与阴性对照组比较,nm-Ce O2各剂量组均具有抑制人乳腺癌Bcap-37细胞裸鼠皮下移植瘤生长的作用,并能促进瘤细胞的变性、坏死和凋亡(P<0.05)。nm-Ce O2高剂量组的肿瘤生长抑制作用低于阳性药组(P<0.05),但nm-Ce O2高、中剂量组促进肿瘤细胞凋亡的作用高于阳性药组(P<0.05)。结论 nm-Ce O2对人乳腺癌Bcap-37细胞裸鼠皮下移植瘤具有显著的生长抑制作用。

Objective To investigate the inhibitory effect of cerium oxide nanoparticles（nm-Ce O2） on the growth of human breast carcinoma Bcap-37 cell xenografts in nude mice.Methods The tumor-bearing nude mouse model was established by transplantion of human breast carcinoma Bcap-37 cells into right infra axillary dermis.BALB / c-nu mice bearing Bcap-37 cells were randomly divided into negative control,positive control and three test groups.The mice in three test groups were treated with nm-Ce O2 at high（300 mg / kg）,middle（100 mg / kg） and low（33.33 mg / kg）dosages by lavage respectively,while those in negative control group with double distilled water at an equal volume,and those in positive group with Cordyceps kyushuensis at a dosage of 2 000 mg / kg,once a day for 17 d.The growths of transplanted tumors in various groups were observed,while the tumor sizes（VT）were measured,the inhibiting rates of tumor growth were calculated,the tumors were weighed,the pathological changes of transplanted tumors were observed,and the apoptosis rates of transplanted tumor cells were determined by terminal dexynucleotidyl transferase mediated d UTP nick end labeling（TUNEL）method.Results Compared with those in negative control group,the tumor growths in three test groups were inhibited significantly,while the degeneration,necrosis and apoptosis of tumor cells were promoted（P〈0.05）.The inhibiting rate of tumor growth in mice treated with nm-Ce O2 at high dosage was significantly lower than that in positive control group（P〈0.05）.However,the apoptosis rates of tumor cells treated with nm-Ce O2 at high and middle dosages were significantly higher than that in positive control group（P〈0.05）.Conclusion The nm-Ce O2 inhibited the growth of human breast carcinoma Bcap-37 cell xenografts in nude mice significantly.