Objective: To investigate the role of transcription factor specificity protein 1 (SP1) in proliferation, migration and invasion in head and neck squamous cell carcinoma (HNSCC), and the role of SP1 in transcription regulation of microRNA (miRNA)-92b. Methods: Predicted the possible target miRNA of transcription factor SP1 by bioinformatic analysis. Furthermore, confirmed the binding sites of transcription factor SP1 and miRNA-92b promoter regions by chromatin immunoprecipitation. After transfecting SP1 siRNA and negative control siRNA, also performed quantitative real-time PCR (qPCR), cell proliferation assay and Transwell assay. Results: The bioinformatic analysis shows SP1 is a possible transcription factor of miRNA-92b. Chromatin immunoprecipitation suggests there are three binding sites in miRNA-92b promoter regions that can be combined with SP1. qPCR suggests in PCI-4A and PCI-37A cells the expression of SP1 in experimental group (respectively was 0.064±0.020 and 0.639±0.008) were significantly lower than negative control group (both were 1)(P<0.05). In PCI-4A and PCI-37A cells the expression of miRNA-92b in experimental group (respectively was 0.215±0.033 and 0.497±0.104) were significantly lower than negative control group (both were 1)(P<0.05). In experimental group proliferation of SP1 in PCI-4A and PCI-37A cells value A were significantly lower than negative control group (P<0.05). In experimental group migration of SP1 in PCI-4A and PCI-37A cells (respectively was 37.0±4.6 and 40.7±2.1) were significantly lower than negative control group (101.0±5.3 and 82.7±5.7) (P<0.05). In experimental group invasion of SP1 in PCI-4A and PCI-37A cells (respectively was 31.3±10.8 and 37.0±4.6) were significantly lower than negative control group (92.3±3.1 and 70.3±3.1)(P<0.05). Conclusions: SP1 promotes proliferation, migration and invasion abilities of HNSCC cells. SP1 is a transcription factor of miRNA-92b and can directly be involved in transcription regulation of miRNA-92b.
目的： 研究转录因子特异蛋白1（specificity protein 1，SP1）对头颈部鳞状细胞癌（head and neck squamous cell carcinoma，HNSCC）细胞增殖、转移和侵袭的影响，以及SP1对微RNA（microRNA，miRNA）-92b的转录调节作用。 方法： 实验分为转染SP1干扰小RNA（small interfering RNA，siRNA）的实验组、转染阴性对照siRNA的阴性对照组和未做处理的空白对照组。应用生物信息学方法预测miRNA-92b的转录因子。采用染色质免疫共沉淀技术验证转录因子SP1与miRNA-92b基因启动子的结合位点。转染siRNA抑制SP1表达后，用实时荧光定量PCR（quantitative real-time PCR，qPCR）检测SP1和miRNA-92b的表达变化。转染后进行细胞增殖实验、Transwell迁移和侵袭实验。 结果： 染色质免疫共沉淀技术表明miRNA-92b启动子区域有3个DNA片段位点与SP1结合。qPCR结果显示，实验组SP1在细胞PCI-4A和PCI-37A中的表达（分别为0.064±0.020和0.639±0.008）显著低于阴性对照组（均为1）（P<0.05），实验组miRNA-92b在细胞PCI-4A和PCI-37A中的表达（分别为0.215±0.033和0.497±0.104）均显著低于阴性对照组（均为1）（P<0.05）。实验组SP1在细胞PCI-4A和PCI-37A中增殖的A值均显著低于阴性对照组（P<0.05）。实验组SP1在细胞PCI-4A和PCI-37A中迁移细胞数（分别为37.0±4.6和40.7±2.1）均显著低于阴性对照组（分别为101.0±5.3和82.7±5.7）（P<0.05）。实验组SP1在细胞PCI-4A和PCI-37A中侵袭细胞数（分别为31.3±10.8和37.0±4.6）均显著低于阴性对照组（分别为92.3±3.1和70.3±3.1）（P<0.05）。 结论： SP1是miRNA-92b的转录因子并直接参与miRNA-92b的转录调控；SP1可以促进HNSCC细胞增殖、迁移和侵袭的能力。.
Keywords: Carcinoma, squamous cell; Cell migration assays; Cell proliferation; MicroRNAs; Sp1 transcription factor.