宫颈癌及其前期病变患者外周血调节T细胞的差异分析

Measurement of CD4^+ CD25^(high)CD127^(low) regulatory T cells in peripheral blood from cervical cancers and precursors

背景与目的:调节性T细胞(regulatory T cells,Treg cells)可以抑制免疫系统的抗肿瘤反应,在恶性肿瘤的发生过程中,外周血中Treg细胞的数量随着疾病的严重程度增加而增加。本研究旨在探讨Treg细胞在宫颈癌发生、发展中可能产生的作用。方法:采用流式细胞术检测61例宫颈鳞癌(squamouscell carcinoma,SCC),8例宫颈腺癌(adenocarcinoma,ADC),41例高级别宫颈上皮内瘤变(high-gradecervical intraepithelial neoplasias,HG-CIN)患者和17例健康女性体检者外周血中Treg细胞占CD4+T细胞的比率。结果:ADC、SCC、HG-CIN患者和健康对照者中Treg细胞占外周血CD4+T细胞的比率(x±s)分别为:(10.73±2.88)%、(10.31±2.45)%、(9.20±2.28)%和(7.88±1.18)%,各组间差异有统计学意义(P=0.001)。在宫颈鳞状上皮病变中,外周血中Treg细胞的水平随着病变的恶性程度增加逐渐升高(SCC>HG-CIN>NLM,P<0.001)。在69例浸润性宫颈癌中,根据2009 FIGO分期,I期为37例,Ⅱ期为32例。17例(24.6%)患者术后被发现有盆腔淋巴结转移。恶性程度较高的肿瘤中Treg细胞的数量高于恶性程度较低的肿瘤,包括FIGOⅡ期高于Ⅰ期[(10.67±2.67)%vs(10.00±2.24)%]、肿瘤直径>4 cm高于肿瘤直径≤4 cm[(10.68±2.31)%vs(10.04±2.63)%]、有盆腔淋巴结转移的肿瘤高于无盆腔淋巴结转移的肿瘤[(11.06±2.56)%vs(10.13±2.44)%]。但统计检验未发现Treg细胞的数量和肿瘤的临床分期、盆腔淋巴结转移、脉管浸润、肿瘤大小及纤维肌壁浸润程度有相关性(P>0.05)。结论:宫颈上皮内瘤变和宫颈癌患者外周血中Treg细胞比例增高,并且与宫颈上皮恶性转化的程度呈正相关,但其在浸润性宫颈癌形成后的进展过程中的作用有待进一步探讨。

Background and purpose： High-risk types of human papillomavims are the causative agents for cervical carcinogenesis. Regulatory T cells （Treg cells） characterized by CD4＋CD25^high CD127^low have been shown to be involved in vires-induced persistent infection. Treg cells are found to be increased in peripheral blood and tumor microenvironment of patients with solid tumors. The aim of this study was to compare the frequencies of Treg cells in the peripheral blood among cervical cancers and its precursors. Methods： Peripheral blood was collected from 61 patients with cervical squamous cell carcinomas （SCC）, 8 patients with cervical adenocarcinomas （ADC）, 41 patientswith high-grade cervical intraepithelial neoplasia （CIN） and 17 normal controls （NLM）. Flow cytometry was employed to measure the frequency of CD4＋CD25^high CD127^low Treg cells among CD4＋ T cells in peripheral blood. The means of frequency of Treg cells were compared among groups using one-way ANOVA and t-test. Results： The frequency of Treg cells among CD4＋ T cells in the peripheral blood （x±s） was （10.73±2.88）%, （10.31±2.45）%, （9.20±2.28）% and （7.88±1.18）% in ADC cases, SCC cases, CIN cases and normal controls, respectively （P=0.001）. Among squamous lesions, the amount of Treg cells was elevated and correlated with the severity of the disease （SCC〉CIN〉NLM, P〈0.001）. The frequencies of Treg cells were higher in ADC cases compared to SCC cases, however, there was no statistic significance （P=0.657）. Among the 69 invasive carcinomas, the mean age was 47.8 （29-70） years old. Thirty- two and 37 patients were diagnosed as stage Ⅰ and stage Ⅱ, respectively （FIGO staging 2009）. Seventeen （24.6%） patients had pelvic lymph node metastasis. There was a trend that advanced cases had more Treg cells in their peripheral blood, however, no statistical difference was found between the amount of Treg cells and any clinico-pathologic parameters, such as FIGO stage [Ⅱ vs Ⅰ： （10.67±2.67）% vs （10.00±2.24）%, P=0.266], tumor size [〉4 cm vs ≤4 cm： （10.68±2.31）% vs （10.04±2.63）%, P=0.284] and lymph node metastasis[positive vs negative： （11.06±2.56）% vs （10.13±2.44）%, P=0.181]. Conclusion： The frequencies of Treg cells in peripheral blood were increased in patients with cervical intraepithelial neoplasia and cervical cancers, which indicated that Treg cells might play a critical role in malignant transformation of cervical intraepithelium. However, their significance in the progression of invasive carcinomas warrants further study.