全反式维甲酸诱导LoVo细胞分化的动物实验研究

Experimental Study on All-trans Retinoic Acid Inducing LoVo Cells Differentiation

研究经全反式维甲酸（ATRA）诱导分化的结肠癌细胞株（LoVo细胞）在裸鼠体内的致瘤性。方法：将ATRA作用下经5次和10次传代的LoVo细胞接种于裸鼠皮下，观察移植瘤生长情况。用扫描电镜观察肿瘤细胞的超微结构，用免疫组化法分析肿瘤细胞癌胚抗原（CEA）的表达及分泌粘液的性质。结果：经5次传代实验组与对照组裸鼠均有移植瘤形成，但实验组移植瘤生长明显受抑制（P＜0．05）。经10次传代实验组裸鼠移植瘤形成抑制率为4／6（P＜0．01）。对照组与实验组移植瘤细胞的形态结构无明显区别，CEA均呈阳性且分泌酸性粘液。结论：ATRA可抑制裸鼠体内移植瘤的生长和形成并呈时间相关性，移植瘤形成可能是LoVo细胞分化不完全所致。

Background/Aims: To investigate the inhibition rate of tumorigenicity of Lovo cells induced by all-trans retinoic acid (ATRA). Methods: LoVo cells induced by ATRA and cultured for 5 and 10 passages were inoculated into the nude mice to observe the growth pattern of the transplanted tumor.Electron microscopy was used for ultrastructures of the tumor cells and to see whether there were any differences between ATRA treated group and control group. Immunohistochemical assay was used to detect the expression of carcinoembryonic antigen (CEA) and mucous excretion from tumor cells.Results: The tumorigenicity of LoVo cells undergone 5 passages was not influenced but the weight of tumor was reduced(P<0.05), whereas tumorigenicity was inhibited after 10 passages, the inhibition rate was 4/6 (P< 0.01). There were no differences in the ultrastructural changes of tumor cells between ATRA treated group and the control group. Immnohistochemical study showed positive expression of CEA and secretion of acidic mucus in both groups. Conclusions: ATRA might inhibit transplanted tumor growth in a time-dependent manner. The formation of transplanted tumor might be related to the incomplete differentiation of LoVo cell induced by ATRA.