Beclin 1与LC3蛋白在腮腺多形性腺瘤及腮腺癌在多形性腺瘤中的表达和意义

Expression and significance of Beclin 1 and LC3 in parotid pleomorphic adenoma and carcinoma in pleomorphic adenoma

目的探讨自体吞噬相关基因Beclin 1和微管相关蛋白1轻链3(microtubule associated protein 1 light chain3,LC3)表达和腮腺肿瘤之间的关系。方法所用组织取自本院2001-2009年手术标本,用免疫组化法和免疫印迹法检测20例正常腮腺组织,37例腮腺多形性腺瘤,41例癌在多形性腺瘤中Beclin 1和LC3的表达,并结合临床病理因素进行分析。结果 Beclin 1、LC3在正常腮腺组织表达为(1.045±0.002)、(0.779±0.047),在腮腺多形性腺瘤中表达下降[(0.419±0.051)、(0.243±0.023),P<0.05],在癌在多形性腺瘤中二者阳性表达显著下降[(0.173±0.008)、(0.051±0.010),P<0.05]。淋巴结转移及TNM分期与Beclin 1的表达间有明显差异(P<0.05),不同侵袭性,不同淋巴结转移组与LC3的表达间有明显差异(P<0.05)。结论 Beclin 1和LC3在腮腺多形性腺瘤及癌在多形性腺瘤中表达下调,自体吞噬功能改变可能在腮腺肿瘤形成过程中具有一定作用。

Objective To detect the expression of Beclin 1 and microtubule associated protein light 1 chain 3 （ LC3 ） in parotid tumor. Methods Clinical data of 98 cases who admitted in our hospital from 2001 to 2009 were collected in this study. The collected tissue samples included 20 cases of normal parotid gland, 37 cases of parotid pleomorphic adenoma and 41 cases of carcinoma in pleomorphic adenoma. The expression of Beclin 1 and LC3 were assessed by immunohistochemistry and Western blotting. The correlation of Beclin 1 and LC3 expression with the elinicopathologie characteristics of the carcinoma in pleomorphic adenoma were analyzed. Results The positive rates of Beclin 1 and LC3 was highly in normal parotid gland （ 1. 045 ±0. 002 and 0.779 _＋0.047）, moderately in parotid pleomorphic adenoma （0. 419±0. 051, 0.243 ±0.023 ; P 〈0.05 vs normal tissue） , and mildly in carcinoma in pleomorphic adenoma （0. 173 ± 0. 008, 0. 051 ±0. 010, P 〈 0. 05 vs normal tissue）. The expression of Beclin 1 showed significant difference with lymph node metastasis and TNM stage （P 〈 0.05 ）. The invasive of the tumor and lymph node metastasis showed significant difference with the LC3 expression （P 〈 0.05 ）. Conclusion The expression of LC3 and Beclin 1 are down-regulated in parotid pleomorphic adenoma and carcinoma in pleomorphic adenoma. The changes of autophagic capacity may be related to the development of parotid gland tumor.