中晚期宫颈癌同期放化疗敏感性相关蛋白的筛选

Screening Concurrent Chemoradiotherapy Sensitivity-associated Proteins in Intermediate Stage and Advanced Cervical Carcinoma

背景与目的:同期放化疗是中晚期宫颈癌治疗的新方法,但尚缺乏有效手段进行治疗前敏感性预测以制定个体化的治疗方案,本研究通过比较同期放化疗高敏感和低敏感中晚期宫颈癌组织之间蛋白质组的差异,为确定中晚期宫颈癌同期放化疗敏感性相关蛋白以预测放化疗的敏感性。方法:收集治疗前的宫颈癌组织标本冻存。在进行同期放化疗后,根据WHO实体瘤疗效判断标准分为高敏感组和低敏感组。提取组织总蛋白,进行2-DE得到凝胶图谱,进行匹配和差异分析,识别两组之间表达差异蛋白点。将这些差异蛋白点切割、酶解后进行MALDI-TOF-MS分析,数据库搜索鉴定蛋白质。应用免疫组化SP法检测部分差异表达蛋白在宫颈癌组织中的表达,并分析临床病理意义。结果:建立了分辨率高、重复性好的宫颈癌同期放化疗高敏感组和低敏感组的双向凝胶电泳图谱,质谱分析成功鉴定出19个差异表达蛋白,其中9个蛋白质在高敏感组高表达,10个蛋白质在高敏感组低表达。免疫组织化学结果显示,HSP70在低敏感组中的表达强度高于高敏感组,S100A9蛋白在高敏感组中的表达强度高于低敏感组。S100A9在高敏感组中的表达率为88.3%(53/60),在低敏感组中的表达率为28.6%(10/35),差异有统计学意义($2=35.34,P<0.001);HSP70在高敏感组中的表达率为21.7%(13/60),在低敏感组中的表达率为85.7%(30/35),差异有统计学意义($2=36.59,P<0.001)。结论:获得了高敏感组和低敏感组宫颈癌组织的蛋白质2-DE图谱,鉴定了部分差异表达蛋白,这些差异表达蛋白与放化疗敏感性有关,可能作为同期放化疗敏感性预测的候选标志物。

BACKGROUND ＆ OBJECTIVE. Concurrent chemoradiotherapy is a new therapy for intermediate stage and advanced cervical carcinoma, but no valid index for prediction of concurrent chemoradiotherapy sensitivity is available. This study was to screen concurrent chemoradiotherapy sensitivityassociated proteins in intermediate stage and advanced cervical carcinoma. METHODS. Biopsy samplJes of 10 cervical carcinoma patients were collected before treatment. According to their responses to concurrent chemoradiotherapy （WHO standard）, the patients were classified into high sensitivity （HS） group （5 patients） and low sensitivity （LS） group （5 patients）. Total protein were extracted from the biopsy samples. Differential proteins were detected by two-dimensional gel electrophoresis （2-DE） and confirmed by matrix assisted laser desorption/ionization time-of-flight mass spectrometry （MALDI-TOF-MS）. Two differentially expressed proteins were further detected by immunohistochemistry in 95 specimens of cervical carcinoma, including 60 high sensitive cases and 35 low sensitive cases. RESULTS. Nineteen differentially expressed proteins were identified. 9 were highly expressed and 10 were lowly expressed in high sensitive group as compared with those in low sensitive group. According to immunohistochemical results, the expression intensity of heat shock protein 70 （HSP70） was higher and that of S100A9 protein was lower in HS group than in LS group; the positive rate of S100A9 was significantly higher and that of HSP70 was significantly lower in HS group than in LS group （88.3% vs. 28.6%, X2= 35.34, P〈0.001; 21.7% vs. 85.7%, X2=36.59, P〈0.001）. CONCLUSIONS. Differentially expressed proteins that related to concurrent chemoradiotherapy sensitivity of cervical carcinoma are identified. They may be candidate biomarkers for prediction of concurrent chemoradiotherapy sensitivity.