Periostin表达对鼻咽癌细胞体外侵袭行为的影响

Effects of periostin expression on the invasiveness of nasopharyngeal carcinoma cells in vitro

目的探讨Periostin表达对体外鼻咽癌(NPC)细胞侵袭行为的影响及其机制。方法采用Western blotting检测激光捕获显微切割纯化的鼻咽癌间质和正常鼻咽黏膜间质、鼻咽癌低转移潜能细胞系6-10B和高转移潜能细胞系5-8F及NIH 3T3成纤维细胞中Periostin的表达水平。应用阳性脂质体法将pCMV-neo-Periostin质粒瞬时转染到NIH 3T3细胞,运用Western blotting检测转染前后NIH 3T3细胞中Periostin的表达水平,利用Boyden小室穿膜侵袭实验检测Periostin蛋白对肿瘤细胞的体外侵袭能力的影响,明胶酶谱法检测其对基质金属蛋白酶(MMPs)活性的影响。结果 Periostin在纯化的鼻咽癌间质中高表达,在纯化的正常鼻咽黏膜间质中及高转移细胞系5-8F中弱表达,在低转移细胞系6-10B及NIH 3T3细胞中不表达。瞬时转染过表达Periostin的NIH3T3细胞中Periostin的表达明显增强。Boyden小室实验提示,分泌蛋白Periostin可明显增强鼻咽癌细胞6-10B的体外侵袭能力,转染组穿膜的细胞数与空白对照组及未转染对照组比较,明显增多(P<0.01);转染组与6-10B细胞共培养后,培养上清中MMPs的活性较对照组明显增强。结论 Periostin蛋白能增强鼻咽癌细胞的侵袭能力,其机制可能与上调MMPs的活性有关。

Objective To investigate the effects and mechanism of periostin on their invasiveness of nasopharyngeal carcinoma cells in vitro. Methods Western blotting was employed to detect the expression levels of periostin in the stroma of nasopharyngeal carcinoma （NPC） and normal nasopharyngeal mueosa （ NNM ） , nasopharyngeal carcinoma cells 6-]0B （low metastatic potential cell line ） and 5-8F （high metastatic potential cell line）, NIH 3T3 fibroblasts. Eukaryotic expression plasmids of periostin were constructed and transfected into NIH 3T3 fibroblasts to obtain transient transfection cells, the expression of periostin was detected by Western blotting in NIH 3T3 cells before and after transfection. The biological effects were observed, including in vitro invasion by Boyden charmber assay, matrix metalloproteinase（MMPs） activation by gelatin zymogram. Results The expression levels of periostin protein varied in the two different metastatic-potential nasopharyngeal carcinoma cell lines and NIH 3T3 fibroblasts. Periostin was not expressed in 6-10B and NIH 3T3 cells, and 5-8F cells showed weak expression in comparison to the stroma of nasopharyngeal carcinoma. Boyden chamber assay indicated that the invasive capacity of 6-10B was significantly promoted by co-culture with Periostin-overexpression NIH 3T3 cells, and further study by gelatin zymogram assay indicated that MMPs in supernatant of periostin-overexpression NIH 3T3 cells co-culture with 6-10B were more active than negative controls and blank controls. Conclusion Periostin overexpression may promote the invasive capacity of nasopharyngeal carcinoma cells in vitro. The action may exert through regulating the activity of MMPs. The study will provide a new idea for finding stromal targets in tumor therapy,and periostin is expected to be a new target to block metastasis of nasopharyngeal carcinoma.