细胞外信号调节激酶1/2表达与HPV16感染及其交互效应在子宫颈癌变中的作用

Effect of extracellular signal-regulated kinas 1/2 expression and HPV16 infection and their interaction in progression of cervical cancerization

目的 探讨细胞外信号调节激酶（p-ERK）1/2表达与HPV16感染在子宫颈癌变中的作用及其交互效应。方法 选取2013年9月至2014年3月在山西省肿瘤医院、山西省妇幼保健院、山西省晋煤集团总医院经组织病理学确诊的正常子宫颈（NC）女性34例、低度子宫颈上皮内瘤变（CINⅠ）患者26例、高度子宫颈上皮内瘤变（CINⅡ/Ⅲ）患者57例和子宫颈鳞状细胞癌（SCC）患者59例为研究对象。采用调查问卷收集研究对象的人口学特征和子宫颈癌相关因素等资料，并采集子宫颈组织标本。采用PCR法检测HPV16感染状况，应用免疫组化法检测子宫颈组织中磷酸化ERK1/2（p-ERK1/2）蛋白的表达情况。同时使用ERK抑制剂U0126对子宫颈癌细胞Siha（HPV16阳性）和C33A（HPV阴性）进行抑制，比较抑制前后细胞的增殖、凋亡情况。结果 随着子宫颈癌变的进展，HPV16感染率（趋势χ^2=17.99，P〈0.001）和p-ERK1/2的表达率（趋势χ^2=10.58，P=0.001）均逐渐升高，HPV16感染与p-ERK1/2蛋白表达在CINⅠ、CINⅡ/Ⅲ、SCC组中均存在正相加交互作用。细胞实验结果显示，ERK抑制后，Siha和C33A细胞均表现为增殖能力降低（Siha：t=6.863，P〈0.001；C33A：t=7.092，P〈0.001）、凋亡率增高（Siha：t=-5.201，P=0.006；C33A：t=-4.335，P=0.005）。ERK抑制后HPV16阳性Siha细胞较HPV阴性C33A细胞增殖指数高（t=7.066，P〈0.001）、凋亡率低（t=-2.431，P=0.057）。结论 p-ERK1/2高表达和HPV16感染均可增加子宫颈癌变风险，两者在子宫颈癌变中存在正相加交互作用。在子宫颈癌细胞增殖凋亡过程中，ERK1/2的活化可能对HPV16感染细胞的作用更为显著。

Objective To investigate the effect of ERK1/2 protein expression and HPV16 infection, as well as their interaction in the cervical carcinogenesis. Methods A total of 176 patients, including 34 cases with normal cervix （NC）, 26 cases with cervical intraepithelial neoplasmⅠ（CINⅠ）, 57 cases with cervical intraepithelial neoplasmⅡ/Ⅲ （CINⅡ/Ⅲ） and 59 cases with cervical squamous cell carcinoma （SCC）, were enrolled from Shanxi Tumor Hospital, Shanxi Maternal and Child Health Center, Jincheng Coal General Hospital from September 2013 to March 2014. The information about their demographic characteristics and risk factors associated with cervical cancer was collected with structural questionnaire, and cervical tissue samples were collected from each subject. HPV16 infection was detected by PCR, and phosphorylation of ERK1/2 （p-ERK1/2） protein expression levels were detected by immunohistochemistry. Meanwhile, cervical cancer cell lines Siha （HPV16 positive） and C33A （HPV negative） were treated with ERK inhibitor U0126 in vitro. Cell proliferation was determined by living cell count, cell cycle and apoptosis was detected by flow cytometry. Results The HPV16 infection rate （trend χ^2=17.99, P〈0.001） and p-ERK1/2 protein high expression （trend χ^2=10.58, P=0.001） increased gradually along with the severity of cervix lesions. There was an additive interaction between HPV16 infection and p-ERK protein expression in the CINⅠ, CINⅡ/Ⅲ and SCC groups. Cell experiments showed that after ERK inhibition, the proliferation of the two cells were reduced （Siha：t=6.863, P〈0.001; C33A：t=7.092, P〈0.001） and the apoptosis were increased （Siha：t=-5.201, P=0.006; C33A：t=-4.335, P=0.005）. After ERK inhibition, the cell proliferation index of Siha （HPV16 positive） was higher than that of C33A （HPV16 negative） （t=7.066, P〈0.001）, but the apoptosis rate of Siha was lower than that of C33A （t=-2.431,P=0.057）. Conclusions HPV16 infection and the high expression of p-ERK1/2 could increase the risk of cervical cancer. And there might be synergistic actions between the two factors in the progression of cervical cancer. The effect of ERK1/2 activation to HPV16 infection cells might be more significant in the process of cervical cancer cell proliferation and apoptosis.