Sonic Hedgehog信号通路与乳腺癌抑癌基因LKB1的相互影响  

Mutual influence between the Sonic Hedgehog signaling pathway and breast cancer suppressor gene LKB1

作　　者：成小林[1] 蒋蓓琦[1] 李正东[1] 傅韵[1] 庄志刚[1] 庄传经[2] 

机构地区：[1]同济大学附属第一妇婴保健院乳腺外科,上海200040 [2]复旦大学附属肿瘤医院乳腺科,上海200032

出　　处：《现代肿瘤医学》2012年第4期658-663,共6页Journal of Modern Oncology

基　　金：上海市自然科学基金资助项目(编号:09zr1424800);上海市级医院新兴前沿技术项目(编号:SHDC12010116)

摘　　要：目的:研究环靶明(cyclopamine)抑制Sonic Hedgehog(SHH)信号通路后,转染LKB1基因的乳癌细胞的凋亡、周期及信号通路相关基因表达的改变。方法:抑癌基因LKB1转染人乳腺癌细胞MDA-MB-231,分MDA-MB-231组(231组)和转染LKB1基因的MDA-MB-231(LKB1组)两组,每组分别采用0,5×10-6mol/L,10×10-6mol/L,20×10-6mol/L 4种浓度的环靶明处理细胞,各小组细胞分别采用流式细胞仪检测细胞凋亡和周期,用RT-PCR法和Western blot法检测Sonic Hedgehog信号通路相关基因Shh、Smo、Ptch、Sufu、Hip及LKB1的mRNA和蛋白表达水平。结果 :在LKB1组和231组中,各小组细胞的凋亡率变化与Sonic Hedgehog相关基因Shh、Smo表达变化一致,随环靶明浓度增大凋亡率增加、基因表达受抑制,在环靶明浓度达10×10-6mol/L时变化最明显,且LKB1组较231组的变化更为明显。在231组中,各小组细胞周期变化与Sonic Hedgehog相关抑制基因Sufu、Hip表达变化一致。而在LKB1组中,各小组细胞周期与抑制基因Sufu、Hip表达变化均无明显差异。在231组中,各小组抑癌基因LKB1的表达随药物浓度增加渐增强。Ptch表达在两组均无明显变化。结论 :抑癌基因LKB1可协同Sonic Hedgehog信号通路抑制剂环靶明促进乳腺癌细胞凋亡,调控细胞周期,推测其机制可能是通过如上信号通路相关基因表达变化而实现。信号通路抑制剂环靶明可提高乳腺癌细胞抑癌基因LKB1的表达,推测此也是信号通路抑制剂降低癌细胞活性机制之一。Objective： To investigate changes of apoptosis,cell cycle and signaling pathway-related gene expression of the cancer cells,under the inhibition of cyclopamine to the Sonic Hedgehog（SHH） signaling pathway of the breast cancer cells transfected with LKB1 genes.Methods： The LKB1 gene was reintroduced into the MDA-MB 231 breast cancer cells which was lack of LKB1.And then 2 groups were classified： the MDA-MB-231 group（231 group） and the LKB1 transfected MDA-MB-231 group（LKB1 group）.The cells in each group were treated with different content（0,5 × 10-6 mol / L,10 × 10-6 mol / L,20 × 10-6 mol / L） of Sonic Hedgehog signaling inhibitor cyclopamine.The apoptosis and cell cycle were detected with flow cytometry.mRNA and protein expression levels of Shh,Smo,Ptch,Sufu,Hip and LKB1 genes which related to Sonic Hedgehog signaling pathway were detected with the methods of RT-PCR and Western blot.Results： In LKB1 group and 231 group,the apoptosis variations of the cells were in consistent with the changes in the expression of Sonic Hedgehog related gene Shh and Smo.With the increase of cyclopamine content,the variations of the apoptosis increased and Shh and Smo gene expressions were inhibited.These variations and inhibitions reached the maxima at a cyclopamine content of 10 × 10-6 mol / L,and the variations and inhibitions were more considerable in the LKB1 group than those in 231 group.In 231 group,the variations of cell cycles consisted with the expression changes of Sonic Hedgehog inhibitor Sufu and Hip.While,in LKB1 group,the cell cycle and the gene expression of Sufu and Hip kept nearly unchanged.In addition,in 231 group,the expression of the tumor suppressor gene LKB1 was enhanced with the cyclopamine content increase.The gene expression of Ptch remained unaffected in both LKB1 group and 231 group.Conclusion： In breast cancer MDA-MB-231 cells,under a synergetic affection of LKB1 tumor suppressor and cyclopamine inhibitor,the apoptosis of breast cancer cells was promoted and the cell cycle w

关 键 词：乳腺癌 Sonic HEDGEHOG信号通路 LKB1基因 凋亡 细胞周期 

分 类 号：R730[医药卫生—肿瘤] R737.9[医药卫生—临床医学]