细胞型朊蛋白在结直肠癌中的表达及其与预后的关系

Expression of cellular prion protein and its relationship with prognosis in colorectal cancer

目的探讨细胞型朊蛋白(PrPC)在结直肠癌(CRC)组织中的表达及其与预后的关系。方法收集2016年1月-2017年1月苏州大学附属太仓医院(太仓市第一人民医院)胃肠外科经手术切除的CRC标本50例及癌旁正常组织标本(距肿瘤组织2 cm以上)30例。采用免疫组化SP法检测PrPC的表达情况,Spearman检验分析CRC组织中PrPC阳性表达与临床病理特征的相关性,Kaplan-Meier法分析PrPC表达与CRC患者预后的关系,多因素Cox比例风险回归模型分析CRC预后的影响因素。结果PrPC在CRC组织中呈高表达,其阳性表达率明显高于癌旁正常组织[68.0%(34/50)vs.20.0%(6/30),P<0.01],且PrPC表达水平与TNM分期、肿瘤浸润深度、肿瘤分化程度、脉管侵犯及淋巴结转移相关(P<0.05)。随访截至2021年1月,除1例失访外,余49例获得完整随访,随访时间为6~68个月,随访期间32例死亡,中位随访时间为48个月。Kaplan-Meier生存曲线分析显示,PrPC阴性表达组患者的生存时间为(62.0±7.0)个月,5年总体生存率为50.3%,PrPC阳性表达组患者的生存时间为(45.0±4.1)个月,5年总体生存率为7.0%;两组生存情况比较,差异有统计学意义(P=0.015)。多因素Cox比例风险回归模型分析显示,TNM分期和PrPC阳性表达是CRC患者预后的独立影响因素(P<0.05)。结论PrPC在CRC组织中呈高表达,且与患者预后不良相关,有望成为判断CRC预后的重要指标。

Objective To explore the expression of cellular prion protein(PrPC)and its relationship with prognosis in colorectal cancer(CRC).Methods A total of 50 CRC tissues and 30 corresponding normal colorectal tissues were selected from the Department of Gastrointestinal Surgery of the First People's Hospital of Taicang City from January 2016 to January 2017.The expression of PrPC was determined by immunohistochemical SP method.Spearman test was used to analyze the correlation between PrPC positive expression and clinicopathological characteristics in CRC tissue.Kaplan-Meier method was used to analyze the relationship between PrPC expression and prognosis of CRC patients,Cox proportional hazards regression model was used to analyze the influencing factors of CRC prognosis.Results High expression of PrPC was shown in CRC tissues,and positive expression rate in CRC tissues was significantly higher than in corresponding normal colorectal tissues[68.0%(34/50)vs.20.0%(6/30),P<0.01],and PrPC expression level was associated with patient TNM stage,depth of tumor invasion,degree of tumor differentiation,presence of vascular invasion and lymph node metastasis(P<0.05).Follow up until January 2021,except for 1 case of loss of follow-up,the remaining 49 cases were fully followed up for 6-68 months.During the follow-up,32 cases died,with a median follow-up of 48 months.Kaplan-Meier survival curve analysis showed that the survival time of the patients in the PrPC negative expression group was(62.0±7.0)months,and the 5-year overall survival rate was 50.3%;the survival time of the PrPC positive expression group was(45.0±4.1)months,the 5-year overall survival rate was 7.0%,the difference was statistically significant in the survival situation was found between the two groups(P=0.015).The results of multivariate Cox regression model analysis showed that TNM stage and positive PrPC expression were independent factors influencing the outcome of CRC patients(P<0.05).Conclusion The high expression of PrPC in CRC tissues is correlated with poor prognosis in CRC patients,suggesting that PrPC is expected to be an important indicator for determining the prognosis of CRC.