末端结合蛋白1 (EB1)在宫颈组织中的表达及其对自噬标志蛋白表达的影响

 目的  探讨末端结合蛋白1 (end binding protein 1,EB1)在宫颈组织中的表达及其对自噬标志蛋白LC3和p62/SQSTM1蛋白表达的影响。方法  免疫组织化学检测EB1在宫颈癌、宫颈息肉和慢性宫颈炎组织中的表达;siRNA干扰方法抑制EB1基因表达,并采用实时荧光定量PCR和Western blot方法检测此时宫颈癌Siha细胞自噬标志蛋白LC3和p62/SQSTM1基因的表达。结果  EB1的表达部位主要集中在细胞核外周的胞质中。EB1在宫颈癌和宫颈息肉中的阳性表达率显著低于宫颈慢性炎性组织(P<0.05),但在阳性表达的宫颈癌组织中,绝大多数间质细胞表现为阴性;EB1在中、低分化宫颈鳞癌组织中的阳性表达率显著低于高分化宫颈鳞癌组织(P<0.05)。当EB1基因表达在宫颈癌Siha细胞中的表达被抑制时,无论是在mRNA还是在蛋白水平,自噬标志蛋白p62/SQSTM1和LC3的表达均显著增加(P<0.05)。结论  EB1在自噬发生较低的宫颈癌组织中阳性表达率低于自噬发生较高的宫颈慢性炎性组织;抑制EB1在宫颈癌Siha细胞中的表达,则自噬标志蛋白p62/SQSTM1和LC3表达改变,这一发现充分证明EB1在宫颈癌的自噬过程中发挥着一定的生物学效应。

The expression of end-binding protein 1 (EB1) in cervical tissues and its effect on the expressions of autophagic biomarkers

Objective  To investigate the expression of end-binding protein 1 (EB1) in cervical tissues and its effect to the expressions of autophagic biomarkers,LC3 and p62/SQSTM1.Methods  The expression of EB1 protein in cervical carcinoma,cervical polyps and chronic cervicitis tissues was detected by mmunohistochemical method.The expression of EB1 in cervical cancer Siha cells was knocked down by siRNA,and then the expressions of autophagic biomarkers,LC3 and p62/SQSTM1 were detected by real-time fluorescent quantitative PCR and Western blot.Results  The EB1 mainly located on the cytoplasm which embraces peripheral of nucleus.The positive expression rate of EB1 in cervical cancer and cervical polyps tissues was significantly lower than those in cervical tissues of chronic inflammation (P<0.05),but the vast majority of interstitial cells were negatively expressed of EB1 in the EB1 positive expression cervical cancer tissues.The positive expression rate of EB1 in middle and low differentiation cervical squamous cell carcinoma tissues was significantly lower than that of high differentiation squamous cell carcinoma tissues (P<0.05).When the expression of EB1 was knocked down in cervical cancer Siha cells by siRNA,the expression of autophagic biomarkers,p62/SQSTM1 and LC3,were significantly increased at both mRNA level and protein level (P<0.05).Conclusions  EB1 in cervical cancer tissues whose autophagy is suppressed is lower expressed than in cervical chronic inflammation tissues whose autophagy is activated.Both p62/SQSTM1 and LC3,the autophagic biomarkers,are dramatically increased in cervical cancer Siha cells when the EB1 expression was suppressed,which indicates EB1 plays a role in autophagy of cervical carcinoma.