HIF-2α及ABCG2在人乳腺癌细胞微球体裸鼠移植瘤组织中的表达及其意义

Expressions of HIF-2α and ABCG2 in mammospheres transplantation tumor tissue in nude mice and their significances

目的:研究缺氧诱导因子2α(HIF-2α)及三磷酸腺苷结合转运蛋白G超家族成员2(ABCG2)在原代无血清悬浮培养人乳腺癌细胞微球体(MSs)裸鼠移植瘤组织中的表达,并探讨MSs具有高动物成瘤性的可能机制。方法:原代乳腺癌组织无血清悬浮培养法获得MSs,将其植入裸鼠体内观察成瘤情况,同时采用人乳腺癌MCF-7细胞悬液种植于同一裸鼠的右侧背部作为实验对照。免疫组织化学法观察移植瘤组织中HIF-2α及ABCG2的表达,Western blotting及RT-PCR技术检测HIF-2α及ABCG2蛋白及mRNA在移植瘤组织中的表达水平。结果:原代MSs具有较强的动物成瘤性。免疫组织化学法,在移植瘤组织中HIF-2α与ABCG2均有表达。Western blotting及RT-PCR,HIF-2α及ABCG2蛋白在MSs移植瘤组织中的表达量明显高于MCF-7细胞移植瘤及瘤旁组织中的表达量(P<0.05);HIF-2αmRNA及ABCG2mRNA在MSs移植瘤组织中的表达量明显高于MCF-7细胞移植瘤组织及瘤旁组织中的表达量(P<0.05)。结论:HIF-2α与ABCG2在MSs裸鼠移植瘤中高表达,推测其为导致MSs具有高动物成瘤性的可能机制。

Objective To detect the expressions of hypoxia inducible factor -2α and ATP-binding cassette super family G2 （ABC G2） in mammospheres （MSs） transplantation tumor tissue in nude mice, and to discuss the possible mechanism of the MSs＇ strong tumor formation ability. Methods The MSs cultured in serum-free media supplemented with growth factors were transplanted in the nude mice, and the growth of the transplantation tumor was recorded. The expressions of HIF-2α and ABCG2 in transplantation tumor tissue were observed by immunohistochemistry. The expressions of HIF-2α and ABCG2 potein and mRNA in transplantation tumor tissue were detected by Western blotting and Real-time RT-PCR. Results The MSs had the stronger tumor formation ability than the MCF-7 cell lines. Immunohistochemistry showed the expressions of HIF-2α and ABCG2 in transplantation tumor tissue in nude miCe. The expressions of HIF-2α and ABCG2 proteins in MSs transplantation tumor tissue were higher than those in MCF-7 transplantation tumor tissue and para-tumor tissue （P〈0. 05）. The expressions of HIF-2α and ABCG2 mRNA in MSs transplantation tumor tissue were higher than those in MCF-7 transplantation tumor tissue and para-tumor tissue （P〈0. 05）. Conclusion There are hith expressions of HIF-2α and ABCG in MSs transplantation tumor tissue. It is speculated that HIF-2α and ABCG may be the possible mechanism of MSs＇ strong tumor formation ability.