转录因子SOX4在口腔扁平苔藓癌变过程中的初步作用研究

Preliminary Study on the Role of the Transcription Factor SOX4 in the Carcinogenesis of Oral Lichen Planus

目的对转录因子SOX4在口腔扁平苔藓(oral lichen planus,OLP)和口腔鳞癌(oral squamous cell carcinoma,OSCC)组织和细胞中的表达进行验证,研究SOX4在OLP癌变过程中是否发挥功能性作用。方法利用液相色谱-质谱联用(LC-MS/MS)技术直接从OLP、OLP-OSCC和OSCC的福尔马林固定石蜡包埋(formalin-fixed paraffin-embedded,FFPE)样本中抽提蛋白并验证,利用RNA干扰技术实现SOX4基因沉默,使用蛋白免疫印迹分析(Western blotting,WB)方法对筛选鉴定出的蛋白SOX4进行表达验证。结果利用LC-MS/MS技术分别从OLP、OLP-OSCC和OSCC的FFPE样本中抽提并鉴定出了96,142和135种蛋白,其中,SOX4只在OLP-OSCC样本中表达。免疫组织化学染色(immunochemistry,IHC)结果显示,SOX4在OLP-OSCC和OSCC组织中呈强阳性表达,在OLP组织中不表达或呈弱阳性表达。WB结果示,SOX4/siRNA转染前在舌鳞状细胞癌细胞系(UM1)细胞中的表达高于对照组,转染后SOX4的表达降低(P<0.05)。结论在表达验证和RNA干扰实验中发现,SOX4在OSCC的UM1细胞中表达发生明显变化,提示SOX4蛋白在OLP向口腔鳞癌转变过程中可能具有促进其发生发展的作用。

Objective To verify the expression of the transcription factor SOX4 in the tissues and cells of oral lichen planus (OLP) and oral squamous cell carcinoma (OSCC) and study whether SOX4 plays a functional role in the OLP carcinogenesis.Methods The protein was extracted directly from the formalin-fixed paraffin-embedded (FFPE) samples of OLP, OLP-associated OSCC (OLP-OSCC) and OSCC by liquid chromatography-mass spectrometry (LC-MS/MS).The gene silencing of SOX4 was achieved by RNA interference.The expression of the identified SOX4 protein was verified by Western blotting.Results The results of the LC-MS/MS analysis showed that 96, 142 and 135 kinds of proteins were extracted and identified from the FFPE samples of OLP, OLP-OSCC and OSCC respectively, and SOX4 was only identified in the OLP-OSCC samples.The results of immunochemistry confirmed that SOX4 was strongly-positively expressed in the OLP-OSCC and OSCC tissues and not or weakly-positively expression in the OLP tissues.The results of Western blotting indicated that the expression of SOX4/siRNA in UM1 cells before transfection was higher than that in the control group, and the expression of SOX4 decreased significantly after transfection ( P <0.05).Conclusion It is found that the expression of SOX4 in the M1 cells of OSCC is significantly altered in the expression validation and RNA interference experiments, which suggests that the SOX4 protein may play a role in promoting the OLP carcinogenesis in oral squamous cell carcinoma.