RCAS1在宫颈癌组织中的表达及其与HPV16感染的关系

Correlation of RCAS1 Expression to Human Papillomavirus 16 (HPV16) Infection in Cervical Cancer

背景与目的:表达在SiSo细胞上的受体结合肿瘤抗原(receptor-binding cancer antigen expressed on SiSo cells,RCAS1)在多种肿瘤组织中呈高表达,并与肿瘤逃避免疫监视有关。本研究检测RCAS1蛋白在宫颈癌组织中的表达及其与HPV16感染的相关性,并探讨其临床意义。方法:采用免疫组化SP(streptavidin-peroxidase)法,分别检测71例宫颈癌、76例宫颈上皮内瘤样病变(CIN)及20例正常宫颈上皮组织中RCAS1蛋白与HPV16E7蛋白的表达,并分析两者的表达与临床病理因素的关系。结果:宫颈癌组织中,RCAS1蛋白主要表达于癌细胞膜和/或细胞浆,HPV16 E7蛋白主要表达于癌细胞核。正常宫颈上皮组织不表达RCAS1蛋白,CIN与宫颈癌组织中RCAS1蛋白的表达率分别为39.47%和77.46%,HPV16 E7蛋白的表达率分别为0.05%、28.94%和61.97%,提示随着宫颈病变恶性程度的进展,RCAS1与HPV16 E7表达均逐渐增强(P<0.05)。低分化宫颈癌组中RCAS1表达显著高于高、中分化宫颈癌组(P=0.002),但与患者年龄、临床分期及组织学分型无关(P>0.05);HPV16 E7在鳞癌组中的表达显著高于腺癌组(P=0.000),但与患者年龄、临床分期、组织学分级无关(P>0.05)。RCAS1的表达与HPV16感染在宫颈癌中的表达呈正相关(r=0.780,P=0.000)。结论:RCAS1基因在宫颈癌组织中表达增强,RCAS1表达强度与宫颈癌恶性程度相关;RCAS1阳性的宫颈癌组织中存在HPV16感染。

BACKGROUND ＆ OBJECTIVE：Receptor-binding cancer antigen expressed on SiSo cells （RCAS1） is highly expressed in various human cancer cells and is related to tumor escape from host immune surveillance. This study was to investigate the correlation of RCAS1 expression to human papillomavirus 16（HPV16） infection in cervical carcinoma, and explore their clinical significance. METHODS. The expression of RCAS1 and HPV16 E7 protein in 71 specimens of cervical carcinoma, 76 specimens of cervical intraepithelial neoplasia, and 20 specimens of normal cervical tissue was detected by SP immunohistochemistry. RESULTS= RCAS1 was mainly expressed on cellular membrane and in cytoplasm of tumor cells, whereas the expression of HPV16 E7 was mainly confined to the nuclei. The positive rate of RCAS1 was 0.00% in normal cervical tissue, 39.47% in cervical intraepithelial neoplasia, and 77.46% in cervical cancer; the positive rate of HPV16 E7 was 0.05% in normal cervical tissue, 28.94% in cervical intraepithelial neoplasia, and 61.97% in cervical cancer. The positive rates of RCAS1 and HPV16 E7 tended to increase along with tumor progression （P〈0.05）. The expression of RCAS1 in cervical cancer was significantly related to histological grade （P=0.002）, but had no correlation to age, clinical stage, and histological classification （P〉0.05）. The expression of HPV16 E7 in cervical cancer was significantly related to histological classification （P〈0.001）, but had no correlation to age, clinical stage, and histological grade （P〉0.05）. RCAS1 expression was positively correlated to HPV16 infection in cervical carcinoma （r=0.780, P〈0.001）. CONCLUSIONS： The expression of RCAS1 in cervical cancer is significantly increased, and has correlation with malignant degree of cervical carcinoma. Some RCASl-positive cervical cancer tissues are infected by HPV16.