Osteoglycin基因表达对小鼠肝癌细胞转移能力的影响

Osteoglycin expression affection on the metastatic capability of murine hepatocarcinoma cells

背景与目的:osteoglycin隶属富含亮氨酸小分子蛋白多糖基因家族成员,参与细胞生长、分化过程的调控。本研究探讨osteoglycin表达与肿瘤细胞转移的关系。方法:构建osteoglycin真核表达载体及反义表达载体,分别转染至小鼠肝癌Hca-F细胞及Hca-P细胞,用RT-PCR及Western印迹法分析osteoglycin表达。体外实验评价osteoglycin表达对肿瘤细胞迁移及侵袭能力的影响;体内实验观察osteoglycin表达对肿瘤细胞淋巴道转移能力的影响。结果:高表达osteoglycin可显著降低Hca-F细胞迁移能力(高、低表达osteoglycin细胞通过PET膜数量分别为45±6及90±5,P<0.01)及侵袭能力(高、低表达osteoglycin细胞通过PET膜数量分别为25±7及65±10,P<0.01),体内实验显示其淋巴结转移率显著下降[高、低表达osteoglycin细胞淋巴结转移率分别为53.3%(16/30)及80%(24/30),P<0.05]。有效抑制osteoglycin表达后,可显著提高Hca-P细胞迁移能力(低、高表达osteoglycin细胞通过PET膜数量分别为46±7及15±6,P<0.01)及侵袭能力(低、高表达osteoglycin细胞通过PET膜数量分别为31±8及8±4,P<0.01),体内实验显示其淋巴结转移率显著增高[低、高表达osteoglycin细胞淋巴结转移率分别为46.7%(14/30)及20%(6/30),P<0.05]。结论:高表达osteoglycin降低小鼠肝癌Hca-F细胞转移能力,低表达osteoglycin提高小鼠肝癌Hca-P细胞转移能力。osteoglycin可能作为转移抑制基因参与肿瘤淋巴结转移过程的调控。

Background and purpose： Osteoglycin belongs to small leucine-rich proteoglycan （SLRP） gene family and might play roles in cell growth and differentiation. Our purpose was to investigate the possible correlation between osteoglycin expression and metastatic behavior of tumor cells. Methods： Eukaryotic expression plasmid of osteoglycin and antisense expression plasmid of osteoglycin were constructed, and transfected into mouse hepatocarcinoma Hca-F cells and Hca-P cells, respectively. RT-PCR and western blot were employed to analysis osteoglycin expression of tumor cells. In vivo, Migration assay and invasion assay were used to observe the correlation between osteoglycin expression and metastatic capacity of tumor cells. In vivo, tumor metastasis assay was employed to evaluate the contribution of osteoglycin expression to the malignant behavior of tumor cells. Results： High expression of osteoglycin via transfecion of osteoglycin gene attenuated both migration capability（the number of tumor cell with high and low expression of osteoglycin migrated through the filter were 45±6 and 90±5,respectively, P〈0.01） and invasion capability（the number of tumor cell with high and low expression of osteoglycin invaded through the filter were 25±7 and 65±10,respectively,P〈0.01）of Hca-F cells, and decreased metastatic potential of Hca-F cells to peripheral lymph nodes in vivo（the lymph node metastatic rates of tumor cell with high and low expression of osteoglycin were 53.3%（16/30） and 80%（24/30）, respectively, P〈0.05）; while, effective suppression of osteoglycin expression in Hca-P cells via osteoglycin shRNA resulted in enhanced activity of both migration capability（the number of tumor cell with low and high expression of osteoglycin migrated through the filter were 46±7 and 15±6,respectively, P〈0.01） and invasion capability（the number of tumor cell with low and high expression of osteoglycin invaded through the filter were 31±8 and 8±4,respectively,P〈0.01） of Hca-P cells, and elevated the metastatic potential of Hca-P cells to peripheral lymph nodes in vivo （the lymph node metastatic rates of tumor cell with low and high expression of osteoglycin were 46.7%（14/30） and 20%（6/30）, respectively,P〈0.05）. Conclusion： High expression of osteoglycin inhibited metastatic behavior of tumor cells, and low expression of osteoglycin enhanced metastatic behavior of tumor cells. Osteoglycin might act as tumor metastasis suppression gene.