TLR3的激活抑制乳腺癌细胞MDA—MB-231的增殖

Stimulation of TLR3 inhibits the proliferation of breast cancer cells MDA-MB-231

目的Toll样受体（TLRs）在肿瘤的发生发展和肿瘤免疫中起到重要的作用，有报道称TLR3的激活能够促进某些肿瘤细胞的凋亡。本研究旨在探讨TLR3的特异性激动剂Poly（I：C）对恶性程度较强的乳腺癌细胞MDA-MB-231增殖与凋亡的影响，并初步探讨其发挥作用的机制。方法反转录PCR检测Toll样受体各个亚型在mRNA水平上的表达；CCK-8细胞活力试剂盒检测不同浓度Poly（I：C）对MDA—MB．231细胞增殖的影响；流式细胞术用AnnexinV—FITC／PI染色检测Poly（I：C）对MDA—MB-231细胞凋亡作用的影响；实时定量反转录PCR检测相关细胞因子的表达变化。结果在mRNA水平上，MDA—MB-231细胞TLRs各亚型中TLR3表达最高；CCK-8检测结果显示Poly（I：C）刺激以后，MDA—MB-231细胞的增殖受到抑制，凋亡试剂盒检测显示Poly（I：C）刺激以后对细胞凋亡没有影响；实时定量PCR显示TNF-α、IFN—β和IFN-γ在Poly（I：C）刺激6h后大约有20倍的升高。结论Poly（I：C）刺激MDA-MB-231细胞后，细胞增殖受到抑制，但其凋亡并不受影响；TNF-α、IFN—β和IFN-γ可能在抑制增殖的过程中发挥一定的作用。

Objective Toll-like receptors （TLRs） play important role in the progression and tumor immunity of some types of cancer, some research have demonstrated that agonist of TLR3 can trigger apoptosis of cancers. This study was proposed to investigate if Poly（I：C）, the specific agonist of TLR3, could impact proliferation or apoptosis of progressive breast cancer cells MDA-MB-231, and to investigate the primary mechanism of the function. Methods Expression ofTLRI-10 mRNA was detected by quantitative real-time reverse transcription-polymerase chain reaction. Cell Counting Kit-8 was used to determine the inhibitory effect of Poly（I：C） on proliferation of MDA- MB-231 cells. Cell apoptosis was assayed by flow cytometry with V-FITC/PI staining. Results First, the toll-like receptors 1-10 were all expressed on MDA-MB-231 cells, while the expression level of TLR8 was lower than that of others. Second, according to the CCK-8, the proliferation of MDA-MB-231 cells was inhibited, but the apoptosis was not affected on the basis of Apoptosis Kit. At last, the mRNA expression of TNF-α,IFN-βand IFN-γ were elevated approximately 20 times after Poly（I：C） stimulation for 6 hours. Conclusion MDA-MB-231 cells express all toll-like receptors on mRNA level, and TLR8 was expressed lower than others. The stimulation of TLR3 with Poly（I：C） can inhibit the proliferation of MDA-MB-231, but had no effect on apoptosis. TNF-α,IFN-βand IFN-γ maybe participate in this process.