乳腺癌转移抑制蛋白1下调PI3K/AKT1通路抑制骨肉瘤细胞转移

Breast cancer metastasis suppressor 1 inhibits HOS cells metastasis by down-regulating PI3K/AKT1 signal pathway

目的探讨乳腺癌转移抑制蛋白1(BRMS1)在骨肉瘤转移中的作用和机制。方法免疫组化检测骨肉瘤组织中BRMS1蛋白表达;荧光定量聚合酶链反应(Q-PCR)法检测8例骨肉瘤组织和8个骨肉瘤细胞系BRMS1 mRNA表达的变化;western blot检测正常成骨细胞系(HOSB)及人骨肉瘤细胞系(OS187、COL、LM7、SJSA、MG63、HOS、SAOS-2、CCH-D)和BRMS1蛋白和AKT1蛋白磷酸化的水平;侵袭小室(Transwell)法检测过表达BRMS1的HOS细胞转移能力的变化。结果骨肉瘤组织中BRMS1蛋白表达较癌旁正常骨组织明显减少。骨肉瘤细胞OS187、COL、LM7、SJSA、MG63、HOS、SAOS-2和CCH-D BRMS1 mRNA和蛋白的表达水平较正常成骨细胞HOSB明显降低,而AKT1蛋白磷酸化水平明显升高。HOS细胞过表达BRMS1后,HOS细胞转移能力和AKT1蛋白磷酸化水平明显降低。运用AKT1蛋白磷酸化抑制剂LY294002明显抑制HOS细胞转移能力。结论 BRMS1可以抑制骨肉瘤细胞HOS细胞转移,其机制可能与抑制AKT1蛋白磷酸化有关。

Objective To explore the effects and mechanism of breast cancer metastasis suppressor 1（ BRMS1） in osteosarcoma metastasis. Methods Immunohistochemistry was used to detect the expression of BRMS1 protein in the osteosarcoma tissue. Quantitative-polymerase chain reaction（ QPCR） was used to analyze BRMS1 in eight samples of osteosarcoma tissue and eight cell lines of osteosarcoma. The levels of BRMS1 protein and the phosphorylation of AKT1 protein in normal human osteoblast cell line HOSB and human osteosarcoma cell lines（ OS187,COL,LM7,SJSA,MG63,HOS,SAOS-2 and CCH-D） were detected by western blot. The metastasis ability of HOS cells that overexpressed BRMS1 were estimated by transwell experiment. Results The BRMS1 mRNA levels in osteosarcoma tissues decreased significantly than that in normal bone tissue. Compared with normal human osteoblast cells HOSB,the levels of BRMS1 mRNA and protein obviously decreased in osteosarcoma cell lines OS187,COL,LM7,SJSA,MG63,HOS,SAOS-2 and CCH-D,but the phosphorylation level of AKT1 protein increased. The metastasis ability of HOS cells was obviously inhibited and the phosphorylation of AKT1 protein of HOS cells decreased after BRMS1 overexpression. The phosphorylation inhibitor of AKT1 protein LY294002 blocked HOS cells metastasis. Conclusion BRMS1 could inhibit HOS cells metastasis and the mechanism may involve with suppression of the phosphorylation of AKT1 protein.