血清MUC1、MUC2及MUC5AC表达与结直肠癌的关系

Relationship between the colorectal cancer and the expression of MUC1,MUC2 and MUC5AC in serum

目的制备黏蛋白(MUC)检测用蛋白芯片,应用该芯片定量检测结直肠癌患者血清中MUC1、MUC2及MUC5AC含量,探讨其与结直肠癌的关系。方法利用MUC1、MUC2及MUC5AC的单抗及多抗,制备黏蛋白芯片,采用免疫荧光原理进行检测,并用癌胚抗原(CEA)作为指标,检测30例结直肠癌患者(结直肠癌组)及30例非肿瘤患者与健康成人(对照组)血清MUC的水平。结果结直肠癌组与对照组比较,血清MUC1(5.25±2.37vs3.65±1.82U/ml,P<0.01),MUC2(4.28±2.14vs2.73±1.63U/ml,P<0.01),MUC5AC(5.04±3.20vs3.16±1.57U/ml,P<0.05)和CEA(8.58±3.48vs5.36±2.58μg/L,P<0.05)水平均显著增高。MUC1、MUC2、MUC5AC的阳性表达与结直肠癌分期无关(P>0.05),而与肿瘤的不同分化程度相关,MUC1、MUC5AC在低分化肿瘤中的表达高于高中分化肿瘤,而MUC2在高中分化肿瘤中阳性表达较多。定量检测血清MUC作为结直肠癌诊断指标的敏感度及特异度均较高,单一MUC中MUC1的敏感度和特异度最好,分别达到82.1%、78.1%,而联合诊断(即3种MUC中至少两种阳性)的敏感度和特异度分别达到96.2%、85.3%。结论应用蛋白芯片技术检测血清MUC1、MUC2及MUC5AC水平,此法诊断结直肠癌的敏感度及特异度较高,可为结直肠癌的早期诊断提供新思路,并对其预后判断提供帮助。

Objective Protein chip for mucin detection was prepared to detect the serum levels of mucinl （MUC1）, mucin2 （MUC2） and micin5ac （MUC5AC） of colorectal cancer patients, and to discuss the relationship between colorectal cancer and the expres sion of MUC1, MUC2 and MUC5AC in sertum.Methods The protein chip was prepared with monoclone and polyclone antibodies for the measuement of the serum levels of MUC1, MUC2 and MUC5AC in 30 patients with colorectal cancer and 30 healthy adults as comrol, using the method of immuno-fluorescence. Results The serum levels of mucin and CEA in colorectal cancer group were higher than that in comrol group. The differences were significant between the two groups concerning MUC1 （5. 25±2. 37 vs 3. 65±1. 82U/ml, P〈0. 01）, MUC2 （4. 28±2. 14 vs 2. 73±1.63U/ml, P〈20. 01）, MUC5AC （5.04±3. 20 vs 3. 16±1.57U/ml, P〈0. 05） and CEA （8. 58±3. 48 vs 5.36±2. 58μg/L, P〈0. 05）. The positive expression of MUC1, MUC2 and MUC5AC had no relationship with the stage of colorectal cancer （P〉0. 05）. The positive expression of mucin was related with the cancer differentiation. The positive expression of MUC1 and MUC5AC was higher when cancer differentiation was low as compared with high and median differentiation, but the positive expression of MUC2 was higher in high and middle cancer differemiation. When the serum level of mucin was used as an indicator for the diagnosis of colorectal cancer, the sensibility and specificity were both higher. The sensibility and specificity of MUC1 were 82. 1% and 78. 1%, respectively, while of combined mucins （at least 2 in 3 mucins were positive） were 96. 2% and 85. 3%, respectively. Conclusion The application of protein chip for mucin detection on the measurement of serum levels of MUC1, MUC2 and MUC5AC is of higher sensibility and specificity in the diagnosis of colorectal cancer. The establishment of protein chip has provided a new approach to early diagnosis of colorec tal cancer, and help estimate the prognosis.