shRNA-CXCR4对人乳腺癌细胞增殖活性的影响

背景与目的：CXCR4足趋化细胞因子SDF—l（基质细胞衍生因子-1）的受体：CXCR4／SDF-1轴在肿瘤侵袭，转移中具有重要作用．阻断CXCR4／SDF-1轴，有可能成为一个新的肿瘤治疗标靶，本研究拟探讨shR-NA—CXCR4对人乳腺癌细胞株MCF-7、MDA—MB-231，MDA．MB435s细胞增殖活性的影响。方法：通过质粒shRNA—CXCR4沉默CXCR4基因后．RT—PCR，Weslernblot检测3株人乳腺癌细胞的CXCR4mRNA及其蛋白的表达；MTT．流式细胞仪检洲它们的增殖结果：质粒shRNA—CXCR4作用于3株人乳腺癌细胞后能明显抑制其CXCR4基因的tuRNA（MDA—MB-23l：实验组CXCR4／GAPDH为0．152．空白组和阴性对照组分圳为0．40及0．45．MDA-MB-435s：实验组为0．198，空白对照组和阴性对朋组分别为0．690及0．775，MCF-7：实验组为0．089，空白对照组和阴性对照组分别为0．327及0．313）及蛋白表达水平（MDA—MB-231：实验组CXCR4／β-actin为0．153，空白组和阴性对照组分圳为0．829及0．878，MDA—MB-435s：实验组为0．173，空白对照组和阴性对照组分别为0．877及0．906，MCF-7：实验组为0．177，空白对照组和阴性对照组分别为0．911及0．874）（P〈0．05）；MTT显示能明显抑制3株人乳腺癌细胞的增殖（P〈0．05）；流式细胞仪显示3株人乳腺癌细胞S期细胞数量明显减少（P〈0．05），将更多的细胞阻滞在G0／G1朗（P〈0．05）结论：shRNA—CXCR4作用于CXCR4基因后能明显抑制人乳腺癌细咆生长和增殖一可能是治疗乳腺癌的一个潜在治疗耙点。

The effect of shRNA-CXCR4 on breast cancer cell growth and proliferation in vitro

Background and purpose:A chemokine receptor,CXCR4,and its endogenous ligand,stromal cell-derived factor-1(SDF-1),have been recognized to be involved in the invasion and metastasis of cancer.Inhibition of CXCR4 may be a new therapeutic target.We studied whether shRNA-CXCR4 could inhibit the CXCR4 gene expression and the proliferation in MCF-7,MDA-MB-231 and MDA-MB-435s breast cancer cells.Methods:Through knockdown CXCR4 by shRNA,the CXCR4 mRNA expression was detected by RT-PCR and the CXCR4 protein expression was mesured by Western blot.The proliferation of breast cancer cells was evaluated by MTT and flow cytometry.Results:The CXCR4mRNA and its protein expression decreased significantly in MCF-7(the average level of CXCR4 mRNA and protein expression were 0.089,0.177 in PG-CXCR4 group,compared with 0.327 and 0.313 for mRNA expression,0.911,0.874 for protein expression in control and PG-HK group),MDA-MB-231(the average level of CXCR4 mRNA and protein expression were 0.152 and 0.153 in PG-CXCR4 group,compared with 0.40 and 0.45 for mRNA expression,0.829 and 0.878 for protein expression in control and PG-HK group)and MDA-MB-435s(the average level of CXCR4 mRNA and protein expression were 0.198 and 0.173 in PG-CXCR4 group,compared with 0.69 and 0.77 for mRNA expression,0.877 and 0.906 for protein expression in control and PG-HK group)breast cancer cells(P<0.05).shRNACXCR4 could inhibit the cell proliferation(P<0.05)and induce the cell cycle arrest at G0/G1 phase with a significant decrease of cells in S phase(P<0.05).Conclusions:Silencing CXCR4 could inhibit the breast cancer growth.It may be a potentially valuable therapeutic target in the treatment of breast cancer.