xCT在鼻咽癌细胞体外迁移侵袭中的作用及机制

Effect and mechanism of xCT on invasion and migration of nasopharyngeal carcinoma cells in vitro

目的 观察xCT基因对鼻咽癌细胞侵袭转移能力的影响并初步探寻其可能机制.方法 实时荧光定量PCR和Western blot检测xCT在鼻咽癌高转移性细胞5-8F与低转移性6-10B细胞中的表达差异;建立过表达xCT的6-10B细胞和敲低xCT的5-8F细胞,用划痕实验及Transwell实验观察干预xCT对细胞迁移侵袭能力的影响;用Western blot检测各组细胞中基质金属蛋白酶1（MMP1）表达的改变.结果 鼻咽癌高转移性细胞5-8F中xCT的mRNA及蛋白表达量均高于低转移性6-10B细胞;外源性过表达xCT增强6-10B细胞的迁移侵袭能力,xCT表达沉默或功能抑制能降低5-8F细胞的迁移侵袭能力;5-8F细胞中MMP1的表达明显高于6-10B细胞,且其表达水平与xCT呈正相关.结论 xCT与鼻咽癌的侵袭转移密切相关,xCT能增强NPC细胞的迁移侵袭能力;xCT可能通过上调MMP1来介导NPC细胞的增殖及侵袭转移.

Objective To explore the role of xCT in the metastasis and drug resistance of nasopharyngeal carcinoma （NPC）,to provide new evidences for the mechanism of NPC metastasis and drug resistance,and to enhance effects of chemotherapy.Methods Fluorescence quantitative polymerase chain reaction （PCR） and Western blot were used to detect the xCT expression of 5-8F and 6-10B.The xCT eukaryotic expression vector was constructed to transient transfect 6-10B cell lines.The 5-8F cell lines were treated with xCT antisense oligodeoxynucleotide （ASO）.Scratching assay and transwell method were used to detect the cell metastasis and invasion abilities.The expressions of matrix metalloproteinase 1 （MMP1） of all the cell lines were surveyed by Western blot.Results The results of fluorescence quantitative PCR and Western blot showed that the expression of xCT in 5-8F was higher than 6-10B in the levels of mRNA and protein.Exogenous overexpression of xCT enhanced metastasis and invasion abilities of 6-10B cells.Silencing and inhibition of xCT could decrease metastasis and invasion abilities of 5-8F cells.The expressions of MMP1 protein in 5-8F were higher than 6-10B,and they were positively correlated with the expression of xCT.Conclusions xCT is closely related to the metastasis and invasion abilities of nasopharyngeal carcinoma.xCT could enhance the metastasis and invasion abilities of NPC cells.xCT might mediate proliferation and matastasis/invasion of NPC cells through MMP1.