膀胱尿路上皮癌中MHC I类链相关蛋白A的表达及临床意义

目的：探讨膀胱尿路上皮癌中MHCI类链相关蛋白A（MICA）的表达及临床意义。方法：用免疫组化检测75例膀胱尿路上皮癌及15例正常膀胱黏膜中MICA蛋白表达，对MICA蛋自在膀胱黏膜、不同级别及分期的膀胱癌中的表达进行统计学分析。结果：MICA蛋白在膀胱癌的表达率（48．0％）高于正常膀胱黏膜（P〈0．05），其中在非浸润性尿路上皮癌的表达率为59．0％（P〈0．05），浸润性36．1％；高、低级别非浸润性癌MICA蛋白表达无统计学意义；MICA蛋白在Ta、T1和T2-4期膀胱癌的表达率分别为59．0％、41．2％和31．6％，MICA蛋白在浸润性膀胱癌（T1-4）的表达低于非浸润性膀胱癌（Ta）（P〈0．05）。结论：MICA蛋白表达上调可能与膀胱尿路上皮癌的发生有关。而MICA蛋白表达缺失可能与膀胱癌的浸润有关。MICA蛋白可作为膀胱癌免疫治疗的候选治疗靶点。

Expression and Clinical Significance of Major Histocompatibility Complex Class I Chain-relatived A Protein in Urothelial Carcinoma of Urinary Bladder

Objective： To investigate the expression and clinical significance of major histocompatibility complex class I chain-relatived A protein（MICA）in urothelial carcinoma of urinary bladder. Methods： MICA expression in 75 urothelial carcinoma tissues and 15 normal mucous membrane tissues of the bladder was detected by immunohistochemistry. The differences between MICA expression in mucous membrane tissues, different grade and stage carcinoma were analyzed by statistics. Results： The expression rates of MICA protein in urothelial carcinoma, noninvasive and invasive umthelial carcinoma were 48.0%, 59.0% and 36.1%, respectively. Up-regulation of MICA expression was found in urothelial carcinoma compared with normal mucous membrane tissues（ P 〈 0.05）. There was no significant difference of MICA expression between low grade noninvasive carcinoma and high grade invasive carcinoma. The MICA expression rates of Ta, T1 and T2-4 stage carcinoma were 59.0%, 41.2% and 31.6%, respectively. Lower MICA expression was detected in in- vasive carcinoma（ P 〈 0.05）. Conclusion： Up-regulation of MICA expression may correlate with the tumorigenesis of urinary bladder. Loss of MICA protein may play a role in tumor invasion. MICA protein may be regarded as a putative target for immunothempy on carcinoma of urinary bladder.